blob: 90c1439549fdf221ab1813b14ae0d5dc74adce45 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/mm/page_alloc.c
3 *
4 * Manages the free list, the system allocates free pages here.
5 * Note that kmalloc() lives in slab.c
6 *
7 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
8 * Swap reorganised 29.12.95, Stephen Tweedie
9 * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999
10 * Reshaped it to be a zoned allocator, Ingo Molnar, Red Hat, 1999
11 * Discontiguous memory support, Kanoj Sarcar, SGI, Nov 1999
12 * Zone balancing, Kanoj Sarcar, SGI, Jan 2000
13 * Per cpu hot/cold page lists, bulk allocation, Martin J. Bligh, Sept 2002
14 * (lots of bits borrowed from Ingo Molnar & Andrew Morton)
15 */
16
Linus Torvalds1da177e2005-04-16 15:20:36 -070017#include <linux/stddef.h>
18#include <linux/mm.h>
19#include <linux/swap.h>
20#include <linux/interrupt.h>
21#include <linux/pagemap.h>
KOSAKI Motohiro10ed2732008-03-04 14:28:32 -080022#include <linux/jiffies.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070023#include <linux/bootmem.h>
Yinghai Luedbe7d22010-08-25 13:39:16 -070024#include <linux/memblock.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070025#include <linux/compiler.h>
Randy Dunlap9f158332005-09-13 01:25:16 -070026#include <linux/kernel.h>
Vegard Nossumb1eeab62008-11-25 16:55:53 +010027#include <linux/kmemcheck.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070028#include <linux/module.h>
29#include <linux/suspend.h>
30#include <linux/pagevec.h>
31#include <linux/blkdev.h>
32#include <linux/slab.h>
David Rientjes5a3135c2007-10-16 23:25:53 -070033#include <linux/oom.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070034#include <linux/notifier.h>
35#include <linux/topology.h>
36#include <linux/sysctl.h>
37#include <linux/cpu.h>
38#include <linux/cpuset.h>
Dave Hansenbdc8cb92005-10-29 18:16:53 -070039#include <linux/memory_hotplug.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070040#include <linux/nodemask.h>
41#include <linux/vmalloc.h>
Christoph Lameter4be38e32006-01-06 00:11:17 -080042#include <linux/mempolicy.h>
Yasunori Goto68113782006-06-23 02:03:11 -070043#include <linux/stop_machine.h>
Mel Gormanc7132162006-09-27 01:49:43 -070044#include <linux/sort.h>
45#include <linux/pfn.h>
Andrew Morton3fcfab12006-10-19 23:28:16 -070046#include <linux/backing-dev.h>
Akinobu Mita933e3122006-12-08 02:39:45 -080047#include <linux/fault-inject.h>
KAMEZAWA Hiroyukia5d76b52007-10-16 01:26:11 -070048#include <linux/page-isolation.h>
KAMEZAWA Hiroyuki52d4b9a2008-10-18 20:28:16 -070049#include <linux/page_cgroup.h>
Thomas Gleixner3ac7fe52008-04-30 00:55:01 -070050#include <linux/debugobjects.h>
Catalin Marinasdbb1f812009-06-11 13:23:19 +010051#include <linux/kmemleak.h>
Robert Jennings925cc712009-12-17 14:44:38 +000052#include <linux/memory.h>
Mel Gorman56de7262010-05-24 14:32:30 -070053#include <linux/compaction.h>
Mel Gorman0d3d0622009-09-21 17:02:44 -070054#include <trace/events/kmem.h>
Wu Fengguang718a3822010-03-10 15:20:43 -080055#include <linux/ftrace_event.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070056
57#include <asm/tlbflush.h>
Andrew Mortonac924c62006-05-15 09:43:59 -070058#include <asm/div64.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070059#include "internal.h"
60
Lee Schermerhorn72812012010-05-26 14:44:56 -070061#ifdef CONFIG_USE_PERCPU_NUMA_NODE_ID
62DEFINE_PER_CPU(int, numa_node);
63EXPORT_PER_CPU_SYMBOL(numa_node);
64#endif
65
Lee Schermerhorn7aac7892010-05-26 14:45:00 -070066#ifdef CONFIG_HAVE_MEMORYLESS_NODES
67/*
68 * N.B., Do NOT reference the '_numa_mem_' per cpu variable directly.
69 * It will not be defined when CONFIG_HAVE_MEMORYLESS_NODES is not defined.
70 * Use the accessor functions set_numa_mem(), numa_mem_id() and cpu_to_mem()
71 * defined in <linux/topology.h>.
72 */
73DEFINE_PER_CPU(int, _numa_mem_); /* Kernel "local memory" node */
74EXPORT_PER_CPU_SYMBOL(_numa_mem_);
75#endif
76
Linus Torvalds1da177e2005-04-16 15:20:36 -070077/*
Christoph Lameter13808912007-10-16 01:25:27 -070078 * Array of node states.
Linus Torvalds1da177e2005-04-16 15:20:36 -070079 */
Christoph Lameter13808912007-10-16 01:25:27 -070080nodemask_t node_states[NR_NODE_STATES] __read_mostly = {
81 [N_POSSIBLE] = NODE_MASK_ALL,
82 [N_ONLINE] = { { [0] = 1UL } },
83#ifndef CONFIG_NUMA
84 [N_NORMAL_MEMORY] = { { [0] = 1UL } },
85#ifdef CONFIG_HIGHMEM
86 [N_HIGH_MEMORY] = { { [0] = 1UL } },
87#endif
88 [N_CPU] = { { [0] = 1UL } },
89#endif /* NUMA */
90};
91EXPORT_SYMBOL(node_states);
92
Ravikiran G Thirumalai6c231b72005-09-06 15:17:45 -070093unsigned long totalram_pages __read_mostly;
Hideo AOKIcb45b0e2006-04-10 22:52:59 -070094unsigned long totalreserve_pages __read_mostly;
Rohit Seth8ad4b1f2006-01-08 01:00:40 -080095int percpu_pagelist_fraction;
Benjamin Herrenschmidtdcce2842009-06-18 13:24:12 +100096gfp_t gfp_allowed_mask __read_mostly = GFP_BOOT_MASK;
Linus Torvalds1da177e2005-04-16 15:20:36 -070097
Rafael J. Wysocki452aa692010-03-05 13:42:13 -080098#ifdef CONFIG_PM_SLEEP
99/*
100 * The following functions are used by the suspend/hibernate code to temporarily
101 * change gfp_allowed_mask in order to avoid using I/O during memory allocations
102 * while devices are suspended. To avoid races with the suspend/hibernate code,
103 * they should always be called with pm_mutex held (gfp_allowed_mask also should
104 * only be modified with pm_mutex held, unless the suspend/hibernate code is
105 * guaranteed not to run in parallel with that modification).
106 */
Rafael J. Wysockic9e664f2010-12-03 22:57:45 +0100107
108static gfp_t saved_gfp_mask;
109
110void pm_restore_gfp_mask(void)
Rafael J. Wysocki452aa692010-03-05 13:42:13 -0800111{
112 WARN_ON(!mutex_is_locked(&pm_mutex));
Rafael J. Wysockic9e664f2010-12-03 22:57:45 +0100113 if (saved_gfp_mask) {
114 gfp_allowed_mask = saved_gfp_mask;
115 saved_gfp_mask = 0;
116 }
Rafael J. Wysocki452aa692010-03-05 13:42:13 -0800117}
118
Rafael J. Wysockic9e664f2010-12-03 22:57:45 +0100119void pm_restrict_gfp_mask(void)
Rafael J. Wysocki452aa692010-03-05 13:42:13 -0800120{
Rafael J. Wysocki452aa692010-03-05 13:42:13 -0800121 WARN_ON(!mutex_is_locked(&pm_mutex));
Rafael J. Wysockic9e664f2010-12-03 22:57:45 +0100122 WARN_ON(saved_gfp_mask);
123 saved_gfp_mask = gfp_allowed_mask;
124 gfp_allowed_mask &= ~GFP_IOFS;
Rafael J. Wysocki452aa692010-03-05 13:42:13 -0800125}
126#endif /* CONFIG_PM_SLEEP */
127
Mel Gormand9c23402007-10-16 01:26:01 -0700128#ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
129int pageblock_order __read_mostly;
130#endif
131
Hugh Dickinsd98c7a02006-02-14 13:52:59 -0800132static void __free_pages_ok(struct page *page, unsigned int order);
David Howellsa226f6c2006-01-06 00:11:08 -0800133
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134/*
135 * results with 256, 32 in the lowmem_reserve sysctl:
136 * 1G machine -> (16M dma, 800M-16M normal, 1G-800M high)
137 * 1G machine -> (16M dma, 784M normal, 224M high)
138 * NORMAL allocation will leave 784M/256 of ram reserved in the ZONE_DMA
139 * HIGHMEM allocation will leave 224M/32 of ram reserved in ZONE_NORMAL
140 * HIGHMEM allocation will (224M+784M)/256 of ram reserved in ZONE_DMA
Andi Kleena2f1b422005-11-05 17:25:53 +0100141 *
142 * TBD: should special case ZONE_DMA32 machines here - in those we normally
143 * don't need any ZONE_NORMAL reservation
Linus Torvalds1da177e2005-04-16 15:20:36 -0700144 */
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700145int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES-1] = {
Christoph Lameter4b51d662007-02-10 01:43:10 -0800146#ifdef CONFIG_ZONE_DMA
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700147 256,
Christoph Lameter4b51d662007-02-10 01:43:10 -0800148#endif
Christoph Lameterfb0e7942006-09-25 23:31:13 -0700149#ifdef CONFIG_ZONE_DMA32
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700150 256,
Christoph Lameterfb0e7942006-09-25 23:31:13 -0700151#endif
Christoph Lametere53ef382006-09-25 23:31:14 -0700152#ifdef CONFIG_HIGHMEM
Mel Gorman2a1e2742007-07-17 04:03:12 -0700153 32,
Christoph Lametere53ef382006-09-25 23:31:14 -0700154#endif
Mel Gorman2a1e2742007-07-17 04:03:12 -0700155 32,
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700156};
Linus Torvalds1da177e2005-04-16 15:20:36 -0700157
158EXPORT_SYMBOL(totalram_pages);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700159
Helge Deller15ad7cd2006-12-06 20:40:36 -0800160static char * const zone_names[MAX_NR_ZONES] = {
Christoph Lameter4b51d662007-02-10 01:43:10 -0800161#ifdef CONFIG_ZONE_DMA
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700162 "DMA",
Christoph Lameter4b51d662007-02-10 01:43:10 -0800163#endif
Christoph Lameterfb0e7942006-09-25 23:31:13 -0700164#ifdef CONFIG_ZONE_DMA32
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700165 "DMA32",
Christoph Lameterfb0e7942006-09-25 23:31:13 -0700166#endif
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700167 "Normal",
Christoph Lametere53ef382006-09-25 23:31:14 -0700168#ifdef CONFIG_HIGHMEM
Mel Gorman2a1e2742007-07-17 04:03:12 -0700169 "HighMem",
Christoph Lametere53ef382006-09-25 23:31:14 -0700170#endif
Mel Gorman2a1e2742007-07-17 04:03:12 -0700171 "Movable",
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700172};
173
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174int min_free_kbytes = 1024;
175
Jan Beulich2c85f512009-09-21 17:03:07 -0700176static unsigned long __meminitdata nr_kernel_pages;
177static unsigned long __meminitdata nr_all_pages;
Yasunori Gotoa3142c82007-05-08 00:23:07 -0700178static unsigned long __meminitdata dma_reserve;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700179
Mel Gormanc7132162006-09-27 01:49:43 -0700180#ifdef CONFIG_ARCH_POPULATES_NODE_MAP
181 /*
Simon Arlott183ff222007-10-20 01:27:18 +0200182 * MAX_ACTIVE_REGIONS determines the maximum number of distinct
Mel Gormanc7132162006-09-27 01:49:43 -0700183 * ranges of memory (RAM) that may be registered with add_active_range().
184 * Ranges passed to add_active_range() will be merged if possible
185 * so the number of times add_active_range() can be called is
186 * related to the number of nodes and the number of holes
187 */
188 #ifdef CONFIG_MAX_ACTIVE_REGIONS
189 /* Allow an architecture to set MAX_ACTIVE_REGIONS to save memory */
190 #define MAX_ACTIVE_REGIONS CONFIG_MAX_ACTIVE_REGIONS
191 #else
192 #if MAX_NUMNODES >= 32
193 /* If there can be many nodes, allow up to 50 holes per node */
194 #define MAX_ACTIVE_REGIONS (MAX_NUMNODES*50)
195 #else
196 /* By default, allow up to 256 distinct regions */
197 #define MAX_ACTIVE_REGIONS 256
198 #endif
199 #endif
200
Jan Beulich98011f52007-07-15 23:38:17 -0700201 static struct node_active_region __meminitdata early_node_map[MAX_ACTIVE_REGIONS];
202 static int __meminitdata nr_nodemap_entries;
203 static unsigned long __meminitdata arch_zone_lowest_possible_pfn[MAX_NR_ZONES];
204 static unsigned long __meminitdata arch_zone_highest_possible_pfn[MAX_NR_ZONES];
Adrian Bunkb69a7282008-07-23 21:28:12 -0700205 static unsigned long __initdata required_kernelcore;
Adrian Bunk484f51f2007-10-16 01:26:03 -0700206 static unsigned long __initdata required_movablecore;
Adrian Bunkb69a7282008-07-23 21:28:12 -0700207 static unsigned long __meminitdata zone_movable_pfn[MAX_NUMNODES];
Mel Gorman2a1e2742007-07-17 04:03:12 -0700208
209 /* movable_zone is the "real" zone pages in ZONE_MOVABLE are taken from */
210 int movable_zone;
211 EXPORT_SYMBOL(movable_zone);
Mel Gormanc7132162006-09-27 01:49:43 -0700212#endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
213
Miklos Szeredi418508c2007-05-23 13:57:55 -0700214#if MAX_NUMNODES > 1
215int nr_node_ids __read_mostly = MAX_NUMNODES;
Christoph Lameter62bc62a2009-06-16 15:32:15 -0700216int nr_online_nodes __read_mostly = 1;
Miklos Szeredi418508c2007-05-23 13:57:55 -0700217EXPORT_SYMBOL(nr_node_ids);
Christoph Lameter62bc62a2009-06-16 15:32:15 -0700218EXPORT_SYMBOL(nr_online_nodes);
Miklos Szeredi418508c2007-05-23 13:57:55 -0700219#endif
220
Mel Gorman9ef9acb2007-10-16 01:25:54 -0700221int page_group_by_mobility_disabled __read_mostly;
222
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700223static void set_pageblock_migratetype(struct page *page, int migratetype)
224{
Mel Gorman49255c62009-06-16 15:31:58 -0700225
226 if (unlikely(page_group_by_mobility_disabled))
227 migratetype = MIGRATE_UNMOVABLE;
228
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700229 set_pageblock_flags_group(page, (unsigned long)migratetype,
230 PB_migrate, PB_migrate_end);
231}
232
Rafael J. Wysocki7f33d492009-06-16 15:32:41 -0700233bool oom_killer_disabled __read_mostly;
234
Nick Piggin13e74442006-01-06 00:10:58 -0800235#ifdef CONFIG_DEBUG_VM
Dave Hansenc6a57e12005-10-29 18:16:52 -0700236static int page_outside_zone_boundaries(struct zone *zone, struct page *page)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700237{
Dave Hansenbdc8cb92005-10-29 18:16:53 -0700238 int ret = 0;
239 unsigned seq;
240 unsigned long pfn = page_to_pfn(page);
Dave Hansenc6a57e12005-10-29 18:16:52 -0700241
Dave Hansenbdc8cb92005-10-29 18:16:53 -0700242 do {
243 seq = zone_span_seqbegin(zone);
244 if (pfn >= zone->zone_start_pfn + zone->spanned_pages)
245 ret = 1;
246 else if (pfn < zone->zone_start_pfn)
247 ret = 1;
248 } while (zone_span_seqretry(zone, seq));
249
250 return ret;
Dave Hansenc6a57e12005-10-29 18:16:52 -0700251}
252
253static int page_is_consistent(struct zone *zone, struct page *page)
254{
Andy Whitcroft14e07292007-05-06 14:49:14 -0700255 if (!pfn_valid_within(page_to_pfn(page)))
Dave Hansenc6a57e12005-10-29 18:16:52 -0700256 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700257 if (zone != page_zone(page))
Dave Hansenc6a57e12005-10-29 18:16:52 -0700258 return 0;
259
260 return 1;
261}
262/*
263 * Temporary debugging check for pages not lying within a given zone.
264 */
265static int bad_range(struct zone *zone, struct page *page)
266{
267 if (page_outside_zone_boundaries(zone, page))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700268 return 1;
Dave Hansenc6a57e12005-10-29 18:16:52 -0700269 if (!page_is_consistent(zone, page))
270 return 1;
271
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272 return 0;
273}
Nick Piggin13e74442006-01-06 00:10:58 -0800274#else
275static inline int bad_range(struct zone *zone, struct page *page)
276{
277 return 0;
278}
279#endif
280
Nick Piggin224abf92006-01-06 00:11:11 -0800281static void bad_page(struct page *page)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282{
Hugh Dickinsd936cf92009-01-06 14:40:12 -0800283 static unsigned long resume;
284 static unsigned long nr_shown;
285 static unsigned long nr_unshown;
286
Wu Fengguang2a7684a2009-09-16 11:50:12 +0200287 /* Don't complain about poisoned pages */
288 if (PageHWPoison(page)) {
289 __ClearPageBuddy(page);
290 return;
291 }
292
Hugh Dickinsd936cf92009-01-06 14:40:12 -0800293 /*
294 * Allow a burst of 60 reports, then keep quiet for that minute;
295 * or allow a steady drip of one report per second.
296 */
297 if (nr_shown == 60) {
298 if (time_before(jiffies, resume)) {
299 nr_unshown++;
300 goto out;
301 }
302 if (nr_unshown) {
Hugh Dickins1e9e6362009-01-06 14:40:13 -0800303 printk(KERN_ALERT
304 "BUG: Bad page state: %lu messages suppressed\n",
Hugh Dickinsd936cf92009-01-06 14:40:12 -0800305 nr_unshown);
306 nr_unshown = 0;
307 }
308 nr_shown = 0;
309 }
310 if (nr_shown++ == 0)
311 resume = jiffies + 60 * HZ;
312
Hugh Dickins1e9e6362009-01-06 14:40:13 -0800313 printk(KERN_ALERT "BUG: Bad page state in process %s pfn:%05lx\n",
Hugh Dickins3dc14742009-01-06 14:40:08 -0800314 current->comm, page_to_pfn(page));
Wu Fengguang718a3822010-03-10 15:20:43 -0800315 dump_page(page);
KAMEZAWA Hiroyuki52d4b9a2008-10-18 20:28:16 -0700316
Linus Torvalds1da177e2005-04-16 15:20:36 -0700317 dump_stack();
Hugh Dickinsd936cf92009-01-06 14:40:12 -0800318out:
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800319 /* Leave bad fields for debug, except PageBuddy could make trouble */
320 __ClearPageBuddy(page);
Randy Dunlap9f158332005-09-13 01:25:16 -0700321 add_taint(TAINT_BAD_PAGE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700322}
323
Linus Torvalds1da177e2005-04-16 15:20:36 -0700324/*
325 * Higher-order pages are called "compound pages". They are structured thusly:
326 *
327 * The first PAGE_SIZE page is called the "head page".
328 *
329 * The remaining PAGE_SIZE pages are called "tail pages".
330 *
331 * All pages have PG_compound set. All pages have their ->private pointing at
332 * the head page (even the head page has this).
333 *
Hugh Dickins41d78ba2006-02-14 13:52:58 -0800334 * The first tail page's ->lru.next holds the address of the compound page's
335 * put_page() function. Its ->lru.prev holds the order of allocation.
336 * This usage means that zero-order pages may not be compound.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700337 */
Hugh Dickinsd98c7a02006-02-14 13:52:59 -0800338
339static void free_compound_page(struct page *page)
340{
Christoph Lameterd85f3382007-05-06 14:49:39 -0700341 __free_pages_ok(page, compound_order(page));
Hugh Dickinsd98c7a02006-02-14 13:52:59 -0800342}
343
Andi Kleen01ad1c02008-07-23 21:27:46 -0700344void prep_compound_page(struct page *page, unsigned long order)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700345{
346 int i;
347 int nr_pages = 1 << order;
348
Andy Whitcroft33f2ef82006-12-06 20:33:32 -0800349 set_compound_page_dtor(page, free_compound_page);
Christoph Lameterd85f3382007-05-06 14:49:39 -0700350 set_compound_order(page, order);
Christoph Lameter6d777952007-05-06 14:49:40 -0700351 __SetPageHead(page);
Andy Whitcroft18229df2008-11-06 12:53:27 -0800352 for (i = 1; i < nr_pages; i++) {
353 struct page *p = page + i;
354
Christoph Lameterd85f3382007-05-06 14:49:39 -0700355 __SetPageTail(p);
Christoph Lameterd85f3382007-05-06 14:49:39 -0700356 p->first_page = page;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700357 }
358}
359
Andrea Arcangeli59ff4212011-01-13 15:46:38 -0800360/* update __split_huge_page_refcount if you change this function */
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800361static int destroy_compound_page(struct page *page, unsigned long order)
Andy Whitcroft18229df2008-11-06 12:53:27 -0800362{
363 int i;
364 int nr_pages = 1 << order;
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800365 int bad = 0;
Andy Whitcroft18229df2008-11-06 12:53:27 -0800366
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800367 if (unlikely(compound_order(page) != order) ||
368 unlikely(!PageHead(page))) {
Nick Piggin224abf92006-01-06 00:11:11 -0800369 bad_page(page);
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800370 bad++;
371 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700372
Christoph Lameter6d777952007-05-06 14:49:40 -0700373 __ClearPageHead(page);
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800374
Andy Whitcroft18229df2008-11-06 12:53:27 -0800375 for (i = 1; i < nr_pages; i++) {
376 struct page *p = page + i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700377
Alexey Zaytseve713a212009-01-10 02:47:57 +0300378 if (unlikely(!PageTail(p) || (p->first_page != page))) {
Nick Piggin224abf92006-01-06 00:11:11 -0800379 bad_page(page);
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800380 bad++;
381 }
Christoph Lameterd85f3382007-05-06 14:49:39 -0700382 __ClearPageTail(p);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700383 }
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800384
385 return bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700386}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700387
Nick Piggin17cf4402006-03-22 00:08:41 -0800388static inline void prep_zero_page(struct page *page, int order, gfp_t gfp_flags)
389{
390 int i;
391
Andrew Morton6626c5d2006-03-22 00:08:42 -0800392 /*
393 * clear_highpage() will use KM_USER0, so it's a bug to use __GFP_ZERO
394 * and __GFP_HIGHMEM from hard or soft interrupt context.
395 */
Nick Piggin725d7042006-09-25 23:30:55 -0700396 VM_BUG_ON((gfp_flags & __GFP_HIGHMEM) && in_interrupt());
Nick Piggin17cf4402006-03-22 00:08:41 -0800397 for (i = 0; i < (1 << order); i++)
398 clear_highpage(page + i);
399}
400
Andrew Morton6aa30012006-04-18 22:20:52 -0700401static inline void set_page_order(struct page *page, int order)
402{
Hugh Dickins4c21e2f2005-10-29 18:16:40 -0700403 set_page_private(page, order);
Nick Piggin676165a2006-04-10 11:21:48 +1000404 __SetPageBuddy(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700405}
406
407static inline void rmv_page_order(struct page *page)
408{
Nick Piggin676165a2006-04-10 11:21:48 +1000409 __ClearPageBuddy(page);
Hugh Dickins4c21e2f2005-10-29 18:16:40 -0700410 set_page_private(page, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700411}
412
413/*
414 * Locate the struct page for both the matching buddy in our
415 * pair (buddy1) and the combined O(n+1) page they form (page).
416 *
417 * 1) Any buddy B1 will have an order O twin B2 which satisfies
418 * the following equation:
419 * B2 = B1 ^ (1 << O)
420 * For example, if the starting buddy (buddy2) is #8 its order
421 * 1 buddy is #10:
422 * B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10
423 *
424 * 2) Any buddy B will have an order O+1 parent P which
425 * satisfies the following equation:
426 * P = B & ~(1 << O)
427 *
Andreas Mohrd6e05ed2006-06-26 18:35:02 +0200428 * Assumption: *_mem_map is contiguous at least up to MAX_ORDER
Linus Torvalds1da177e2005-04-16 15:20:36 -0700429 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700430static inline unsigned long
KyongHo Cho43506fa2011-01-13 15:47:24 -0800431__find_buddy_index(unsigned long page_idx, unsigned int order)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700432{
KyongHo Cho43506fa2011-01-13 15:47:24 -0800433 return page_idx ^ (1 << order);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700434}
435
436/*
437 * This function checks whether a page is free && is the buddy
438 * we can do coalesce a page and its buddy if
Nick Piggin13e74442006-01-06 00:10:58 -0800439 * (a) the buddy is not in a hole &&
Nick Piggin676165a2006-04-10 11:21:48 +1000440 * (b) the buddy is in the buddy system &&
Andy Whitcroftcb2b95e2006-06-23 02:03:01 -0700441 * (c) a page and its buddy have the same order &&
442 * (d) a page and its buddy are in the same zone.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700443 *
Andrea Arcangeli5f24ce52011-01-13 15:47:00 -0800444 * For recording whether a page is in the buddy system, we set ->_mapcount -2.
445 * Setting, clearing, and testing _mapcount -2 is serialized by zone->lock.
Nick Piggin676165a2006-04-10 11:21:48 +1000446 *
447 * For recording page's order, we use page_private(page).
Linus Torvalds1da177e2005-04-16 15:20:36 -0700448 */
Andy Whitcroftcb2b95e2006-06-23 02:03:01 -0700449static inline int page_is_buddy(struct page *page, struct page *buddy,
450 int order)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700451{
Andy Whitcroft14e07292007-05-06 14:49:14 -0700452 if (!pfn_valid_within(page_to_pfn(buddy)))
Nick Piggin13e74442006-01-06 00:10:58 -0800453 return 0;
Nick Piggin13e74442006-01-06 00:10:58 -0800454
Andy Whitcroftcb2b95e2006-06-23 02:03:01 -0700455 if (page_zone_id(page) != page_zone_id(buddy))
456 return 0;
457
458 if (PageBuddy(buddy) && page_order(buddy) == order) {
Nick Piggina3af9c32009-06-16 15:32:10 -0700459 VM_BUG_ON(page_count(buddy) != 0);
Andrew Morton6aa30012006-04-18 22:20:52 -0700460 return 1;
Nick Piggin676165a2006-04-10 11:21:48 +1000461 }
Andrew Morton6aa30012006-04-18 22:20:52 -0700462 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700463}
464
465/*
466 * Freeing function for a buddy system allocator.
467 *
468 * The concept of a buddy system is to maintain direct-mapped table
469 * (containing bit values) for memory blocks of various "orders".
470 * The bottom level table contains the map for the smallest allocatable
471 * units of memory (here, pages), and each level above it describes
472 * pairs of units from the levels below, hence, "buddies".
473 * At a high level, all that happens here is marking the table entry
474 * at the bottom level available, and propagating the changes upward
475 * as necessary, plus some accounting needed to play nicely with other
476 * parts of the VM system.
477 * At each level, we keep a list of pages, which are heads of continuous
Andrea Arcangeli5f24ce52011-01-13 15:47:00 -0800478 * free pages of length of (1 << order) and marked with _mapcount -2. Page's
Hugh Dickins4c21e2f2005-10-29 18:16:40 -0700479 * order is recorded in page_private(page) field.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700480 * So when we are allocating or freeing one, we can derive the state of the
481 * other. That is, if we allocate a small block, and both were
482 * free, the remainder of the region must be split into blocks.
483 * If a block is freed, and its buddy is also free, then this
484 * triggers coalescing into a block of larger size.
485 *
486 * -- wli
487 */
488
Nick Piggin48db57f2006-01-08 01:00:42 -0800489static inline void __free_one_page(struct page *page,
Mel Gormaned0ae212009-06-16 15:32:07 -0700490 struct zone *zone, unsigned int order,
491 int migratetype)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700492{
493 unsigned long page_idx;
Corrado Zoccolo6dda9d52010-05-24 14:31:54 -0700494 unsigned long combined_idx;
KyongHo Cho43506fa2011-01-13 15:47:24 -0800495 unsigned long uninitialized_var(buddy_idx);
Corrado Zoccolo6dda9d52010-05-24 14:31:54 -0700496 struct page *buddy;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700497
Nick Piggin224abf92006-01-06 00:11:11 -0800498 if (unlikely(PageCompound(page)))
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800499 if (unlikely(destroy_compound_page(page, order)))
500 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700501
Mel Gormaned0ae212009-06-16 15:32:07 -0700502 VM_BUG_ON(migratetype == -1);
503
Linus Torvalds1da177e2005-04-16 15:20:36 -0700504 page_idx = page_to_pfn(page) & ((1 << MAX_ORDER) - 1);
505
Mel Gormanf2260e62009-06-16 15:32:13 -0700506 VM_BUG_ON(page_idx & ((1 << order) - 1));
Nick Piggin725d7042006-09-25 23:30:55 -0700507 VM_BUG_ON(bad_range(zone, page));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700508
Linus Torvalds1da177e2005-04-16 15:20:36 -0700509 while (order < MAX_ORDER-1) {
KyongHo Cho43506fa2011-01-13 15:47:24 -0800510 buddy_idx = __find_buddy_index(page_idx, order);
511 buddy = page + (buddy_idx - page_idx);
Andy Whitcroftcb2b95e2006-06-23 02:03:01 -0700512 if (!page_is_buddy(page, buddy, order))
Andy Whitcroft3c82d0c2008-07-23 21:27:11 -0700513 break;
Nick Piggin13e74442006-01-06 00:10:58 -0800514
Andy Whitcroft3c82d0c2008-07-23 21:27:11 -0700515 /* Our buddy is free, merge with it and move up one order. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700516 list_del(&buddy->lru);
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700517 zone->free_area[order].nr_free--;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700518 rmv_page_order(buddy);
KyongHo Cho43506fa2011-01-13 15:47:24 -0800519 combined_idx = buddy_idx & page_idx;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700520 page = page + (combined_idx - page_idx);
521 page_idx = combined_idx;
522 order++;
523 }
524 set_page_order(page, order);
Corrado Zoccolo6dda9d52010-05-24 14:31:54 -0700525
526 /*
527 * If this is not the largest possible page, check if the buddy
528 * of the next-highest order is free. If it is, it's possible
529 * that pages are being freed that will coalesce soon. In case,
530 * that is happening, add the free page to the tail of the list
531 * so it's less likely to be used soon and more likely to be merged
532 * as a higher order page
533 */
Mel Gormanb7f50cf2010-10-26 14:21:11 -0700534 if ((order < MAX_ORDER-2) && pfn_valid_within(page_to_pfn(buddy))) {
Corrado Zoccolo6dda9d52010-05-24 14:31:54 -0700535 struct page *higher_page, *higher_buddy;
KyongHo Cho43506fa2011-01-13 15:47:24 -0800536 combined_idx = buddy_idx & page_idx;
537 higher_page = page + (combined_idx - page_idx);
538 buddy_idx = __find_buddy_index(combined_idx, order + 1);
539 higher_buddy = page + (buddy_idx - combined_idx);
Corrado Zoccolo6dda9d52010-05-24 14:31:54 -0700540 if (page_is_buddy(higher_page, higher_buddy, order + 1)) {
541 list_add_tail(&page->lru,
542 &zone->free_area[order].free_list[migratetype]);
543 goto out;
544 }
545 }
546
547 list_add(&page->lru, &zone->free_area[order].free_list[migratetype]);
548out:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700549 zone->free_area[order].nr_free++;
550}
551
KOSAKI Motohiro092cead2009-06-16 15:32:17 -0700552/*
553 * free_page_mlock() -- clean up attempts to free and mlocked() page.
554 * Page should not be on lru, so no need to fix that up.
555 * free_pages_check() will verify...
556 */
557static inline void free_page_mlock(struct page *page)
558{
KOSAKI Motohiro092cead2009-06-16 15:32:17 -0700559 __dec_zone_page_state(page, NR_MLOCK);
560 __count_vm_event(UNEVICTABLE_MLOCKFREED);
561}
KOSAKI Motohiro092cead2009-06-16 15:32:17 -0700562
Nick Piggin224abf92006-01-06 00:11:11 -0800563static inline int free_pages_check(struct page *page)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700564{
Nick Piggin92be2e32006-01-06 00:10:57 -0800565 if (unlikely(page_mapcount(page) |
566 (page->mapping != NULL) |
Nick Piggina3af9c32009-06-16 15:32:10 -0700567 (atomic_read(&page->_count) != 0) |
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800568 (page->flags & PAGE_FLAGS_CHECK_AT_FREE))) {
Nick Piggin224abf92006-01-06 00:11:11 -0800569 bad_page(page);
Hugh Dickins79f4b7b2009-01-06 14:40:05 -0800570 return 1;
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800571 }
Hugh Dickins79f4b7b2009-01-06 14:40:05 -0800572 if (page->flags & PAGE_FLAGS_CHECK_AT_PREP)
573 page->flags &= ~PAGE_FLAGS_CHECK_AT_PREP;
574 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700575}
576
577/*
Mel Gorman5f8dcc22009-09-21 17:03:19 -0700578 * Frees a number of pages from the PCP lists
Linus Torvalds1da177e2005-04-16 15:20:36 -0700579 * Assumes all pages on list are in same zone, and of same order.
Renaud Lienhart207f36e2005-09-10 00:26:59 -0700580 * count is the number of pages to free.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700581 *
582 * If the zone was previously in an "all pages pinned" state then look to
583 * see if this freeing clears that state.
584 *
585 * And clear the zone's pages_scanned counter, to hold off the "all pages are
586 * pinned" detection logic.
587 */
Mel Gorman5f8dcc22009-09-21 17:03:19 -0700588static void free_pcppages_bulk(struct zone *zone, int count,
589 struct per_cpu_pages *pcp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700590{
Mel Gorman5f8dcc22009-09-21 17:03:19 -0700591 int migratetype = 0;
Mel Gormana6f9edd2009-09-21 17:03:20 -0700592 int batch_free = 0;
Mel Gorman72853e22010-09-09 16:38:16 -0700593 int to_free = count;
Mel Gorman5f8dcc22009-09-21 17:03:19 -0700594
Nick Pigginc54ad302006-01-06 00:10:56 -0800595 spin_lock(&zone->lock);
KOSAKI Motohiro93e4a892010-03-05 13:41:55 -0800596 zone->all_unreclaimable = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700597 zone->pages_scanned = 0;
Mel Gormanf2260e62009-06-16 15:32:13 -0700598
Mel Gorman72853e22010-09-09 16:38:16 -0700599 while (to_free) {
Nick Piggin48db57f2006-01-08 01:00:42 -0800600 struct page *page;
Mel Gorman5f8dcc22009-09-21 17:03:19 -0700601 struct list_head *list;
Nick Piggin48db57f2006-01-08 01:00:42 -0800602
Mel Gorman5f8dcc22009-09-21 17:03:19 -0700603 /*
Mel Gormana6f9edd2009-09-21 17:03:20 -0700604 * Remove pages from lists in a round-robin fashion. A
605 * batch_free count is maintained that is incremented when an
606 * empty list is encountered. This is so more pages are freed
607 * off fuller lists instead of spinning excessively around empty
608 * lists
Mel Gorman5f8dcc22009-09-21 17:03:19 -0700609 */
610 do {
Mel Gormana6f9edd2009-09-21 17:03:20 -0700611 batch_free++;
Mel Gorman5f8dcc22009-09-21 17:03:19 -0700612 if (++migratetype == MIGRATE_PCPTYPES)
613 migratetype = 0;
614 list = &pcp->lists[migratetype];
615 } while (list_empty(list));
616
Mel Gormana6f9edd2009-09-21 17:03:20 -0700617 do {
618 page = list_entry(list->prev, struct page, lru);
619 /* must delete as __free_one_page list manipulates */
620 list_del(&page->lru);
Hugh Dickinsa7016232010-01-29 17:46:34 +0000621 /* MIGRATE_MOVABLE list may include MIGRATE_RESERVEs */
622 __free_one_page(page, zone, 0, page_private(page));
623 trace_mm_page_pcpu_drain(page, 0, page_private(page));
Mel Gorman72853e22010-09-09 16:38:16 -0700624 } while (--to_free && --batch_free && !list_empty(list));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700625 }
Mel Gorman72853e22010-09-09 16:38:16 -0700626 __mod_zone_page_state(zone, NR_FREE_PAGES, count);
Nick Pigginc54ad302006-01-06 00:10:56 -0800627 spin_unlock(&zone->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700628}
629
Mel Gormaned0ae212009-06-16 15:32:07 -0700630static void free_one_page(struct zone *zone, struct page *page, int order,
631 int migratetype)
Nick Piggin48db57f2006-01-08 01:00:42 -0800632{
Christoph Lameter006d22d2006-09-25 23:31:48 -0700633 spin_lock(&zone->lock);
KOSAKI Motohiro93e4a892010-03-05 13:41:55 -0800634 zone->all_unreclaimable = 0;
Christoph Lameter006d22d2006-09-25 23:31:48 -0700635 zone->pages_scanned = 0;
Mel Gormanf2260e62009-06-16 15:32:13 -0700636
Mel Gormaned0ae212009-06-16 15:32:07 -0700637 __free_one_page(page, zone, order, migratetype);
Mel Gorman72853e22010-09-09 16:38:16 -0700638 __mod_zone_page_state(zone, NR_FREE_PAGES, 1 << order);
Christoph Lameter006d22d2006-09-25 23:31:48 -0700639 spin_unlock(&zone->lock);
Nick Piggin48db57f2006-01-08 01:00:42 -0800640}
641
KOSAKI Motohiroec95f532010-05-24 14:32:38 -0700642static bool free_pages_prepare(struct page *page, unsigned int order)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700643{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700644 int i;
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800645 int bad = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700646
Li Hongf6503162010-03-05 13:41:52 -0800647 trace_mm_page_free_direct(page, order);
Vegard Nossumb1eeab62008-11-25 16:55:53 +0100648 kmemcheck_free_shadow(page, order);
649
Andrea Arcangeli8dd60a32011-01-13 15:46:34 -0800650 if (PageAnon(page))
651 page->mapping = NULL;
652 for (i = 0; i < (1 << order); i++)
653 bad += free_pages_check(page + i);
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800654 if (bad)
KOSAKI Motohiroec95f532010-05-24 14:32:38 -0700655 return false;
Hugh Dickins689bceb2005-11-21 21:32:20 -0800656
Thomas Gleixner3ac7fe52008-04-30 00:55:01 -0700657 if (!PageHighMem(page)) {
Nick Piggin9858db52006-10-11 01:21:30 -0700658 debug_check_no_locks_freed(page_address(page),PAGE_SIZE<<order);
Thomas Gleixner3ac7fe52008-04-30 00:55:01 -0700659 debug_check_no_obj_freed(page_address(page),
660 PAGE_SIZE << order);
661 }
Nick Piggindafb1362006-10-11 01:21:30 -0700662 arch_free_page(page, order);
Nick Piggin48db57f2006-01-08 01:00:42 -0800663 kernel_map_pages(page, 1 << order, 0);
Nick Piggindafb1362006-10-11 01:21:30 -0700664
KOSAKI Motohiroec95f532010-05-24 14:32:38 -0700665 return true;
666}
667
668static void __free_pages_ok(struct page *page, unsigned int order)
669{
670 unsigned long flags;
671 int wasMlocked = __TestClearPageMlocked(page);
672
673 if (!free_pages_prepare(page, order))
674 return;
675
Nick Pigginc54ad302006-01-06 00:10:56 -0800676 local_irq_save(flags);
Johannes Weinerc2773312009-06-19 19:30:56 +0200677 if (unlikely(wasMlocked))
Mel Gormanda456f12009-06-16 15:32:08 -0700678 free_page_mlock(page);
Christoph Lameterf8891e52006-06-30 01:55:45 -0700679 __count_vm_events(PGFREE, 1 << order);
Mel Gormaned0ae212009-06-16 15:32:07 -0700680 free_one_page(page_zone(page), page, order,
681 get_pageblock_migratetype(page));
Nick Pigginc54ad302006-01-06 00:10:56 -0800682 local_irq_restore(flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700683}
684
David Howellsa226f6c2006-01-06 00:11:08 -0800685/*
686 * permit the bootmem allocator to evade page validation on high-order frees
687 */
Yasunori Gotoaf370fb2008-07-23 21:28:17 -0700688void __meminit __free_pages_bootmem(struct page *page, unsigned int order)
David Howellsa226f6c2006-01-06 00:11:08 -0800689{
690 if (order == 0) {
691 __ClearPageReserved(page);
692 set_page_count(page, 0);
Nick Piggin7835e982006-03-22 00:08:40 -0800693 set_page_refcounted(page);
Nick Piggin545b1ea2006-03-22 00:08:07 -0800694 __free_page(page);
David Howellsa226f6c2006-01-06 00:11:08 -0800695 } else {
David Howellsa226f6c2006-01-06 00:11:08 -0800696 int loop;
697
Nick Piggin545b1ea2006-03-22 00:08:07 -0800698 prefetchw(page);
David Howellsa226f6c2006-01-06 00:11:08 -0800699 for (loop = 0; loop < BITS_PER_LONG; loop++) {
700 struct page *p = &page[loop];
701
Nick Piggin545b1ea2006-03-22 00:08:07 -0800702 if (loop + 1 < BITS_PER_LONG)
703 prefetchw(p + 1);
David Howellsa226f6c2006-01-06 00:11:08 -0800704 __ClearPageReserved(p);
705 set_page_count(p, 0);
706 }
707
Nick Piggin7835e982006-03-22 00:08:40 -0800708 set_page_refcounted(page);
Nick Piggin545b1ea2006-03-22 00:08:07 -0800709 __free_pages(page, order);
David Howellsa226f6c2006-01-06 00:11:08 -0800710 }
711}
712
Linus Torvalds1da177e2005-04-16 15:20:36 -0700713
714/*
715 * The order of subdivision here is critical for the IO subsystem.
716 * Please do not alter this order without good reasons and regression
717 * testing. Specifically, as large blocks of memory are subdivided,
718 * the order in which smaller blocks are delivered depends on the order
719 * they're subdivided in this function. This is the primary factor
720 * influencing the order in which pages are delivered to the IO
721 * subsystem according to empirical testing, and this is also justified
722 * by considering the behavior of a buddy system containing a single
723 * large block of memory acted on by a series of small allocations.
724 * This behavior is a critical factor in sglist merging's success.
725 *
726 * -- wli
727 */
Nick Piggin085cc7d2006-01-06 00:11:01 -0800728static inline void expand(struct zone *zone, struct page *page,
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700729 int low, int high, struct free_area *area,
730 int migratetype)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700731{
732 unsigned long size = 1 << high;
733
734 while (high > low) {
735 area--;
736 high--;
737 size >>= 1;
Nick Piggin725d7042006-09-25 23:30:55 -0700738 VM_BUG_ON(bad_range(zone, &page[size]));
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700739 list_add(&page[size].lru, &area->free_list[migratetype]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700740 area->nr_free++;
741 set_page_order(&page[size], high);
742 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700743}
744
Linus Torvalds1da177e2005-04-16 15:20:36 -0700745/*
746 * This page is about to be returned from the page allocator
747 */
Wu Fengguang2a7684a2009-09-16 11:50:12 +0200748static inline int check_new_page(struct page *page)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700749{
Nick Piggin92be2e32006-01-06 00:10:57 -0800750 if (unlikely(page_mapcount(page) |
751 (page->mapping != NULL) |
Nick Piggina3af9c32009-06-16 15:32:10 -0700752 (atomic_read(&page->_count) != 0) |
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800753 (page->flags & PAGE_FLAGS_CHECK_AT_PREP))) {
Nick Piggin224abf92006-01-06 00:11:11 -0800754 bad_page(page);
Hugh Dickins689bceb2005-11-21 21:32:20 -0800755 return 1;
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800756 }
Wu Fengguang2a7684a2009-09-16 11:50:12 +0200757 return 0;
758}
759
760static int prep_new_page(struct page *page, int order, gfp_t gfp_flags)
761{
762 int i;
763
764 for (i = 0; i < (1 << order); i++) {
765 struct page *p = page + i;
766 if (unlikely(check_new_page(p)))
767 return 1;
768 }
Hugh Dickins689bceb2005-11-21 21:32:20 -0800769
Hugh Dickins4c21e2f2005-10-29 18:16:40 -0700770 set_page_private(page, 0);
Nick Piggin7835e982006-03-22 00:08:40 -0800771 set_page_refcounted(page);
Nick Piggincc102502006-12-06 20:32:00 -0800772
773 arch_alloc_page(page, order);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700774 kernel_map_pages(page, 1 << order, 1);
Nick Piggin17cf4402006-03-22 00:08:41 -0800775
776 if (gfp_flags & __GFP_ZERO)
777 prep_zero_page(page, order, gfp_flags);
778
779 if (order && (gfp_flags & __GFP_COMP))
780 prep_compound_page(page, order);
781
Hugh Dickins689bceb2005-11-21 21:32:20 -0800782 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700783}
784
Mel Gorman56fd56b2007-10-16 01:25:58 -0700785/*
786 * Go through the free lists for the given migratetype and remove
787 * the smallest available page from the freelists
788 */
Mel Gorman728ec982009-06-16 15:32:04 -0700789static inline
790struct page *__rmqueue_smallest(struct zone *zone, unsigned int order,
Mel Gorman56fd56b2007-10-16 01:25:58 -0700791 int migratetype)
792{
793 unsigned int current_order;
794 struct free_area * area;
795 struct page *page;
796
797 /* Find a page of the appropriate size in the preferred list */
798 for (current_order = order; current_order < MAX_ORDER; ++current_order) {
799 area = &(zone->free_area[current_order]);
800 if (list_empty(&area->free_list[migratetype]))
801 continue;
802
803 page = list_entry(area->free_list[migratetype].next,
804 struct page, lru);
805 list_del(&page->lru);
806 rmv_page_order(page);
807 area->nr_free--;
Mel Gorman56fd56b2007-10-16 01:25:58 -0700808 expand(zone, page, order, current_order, area, migratetype);
809 return page;
810 }
811
812 return NULL;
813}
814
815
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700816/*
817 * This array describes the order lists are fallen back to when
818 * the free lists for the desirable migrate type are depleted
819 */
820static int fallbacks[MIGRATE_TYPES][MIGRATE_TYPES-1] = {
Mel Gorman64c5e132007-10-16 01:25:59 -0700821 [MIGRATE_UNMOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_MOVABLE, MIGRATE_RESERVE },
822 [MIGRATE_RECLAIMABLE] = { MIGRATE_UNMOVABLE, MIGRATE_MOVABLE, MIGRATE_RESERVE },
823 [MIGRATE_MOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE, MIGRATE_RESERVE },
824 [MIGRATE_RESERVE] = { MIGRATE_RESERVE, MIGRATE_RESERVE, MIGRATE_RESERVE }, /* Never used */
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700825};
826
Mel Gormanc361be52007-10-16 01:25:51 -0700827/*
828 * Move the free pages in a range to the free lists of the requested type.
Mel Gormand9c23402007-10-16 01:26:01 -0700829 * Note that start_page and end_pages are not aligned on a pageblock
Mel Gormanc361be52007-10-16 01:25:51 -0700830 * boundary. If alignment is required, use move_freepages_block()
831 */
Adrian Bunkb69a7282008-07-23 21:28:12 -0700832static int move_freepages(struct zone *zone,
833 struct page *start_page, struct page *end_page,
834 int migratetype)
Mel Gormanc361be52007-10-16 01:25:51 -0700835{
836 struct page *page;
837 unsigned long order;
Mel Gormand1003132007-10-16 01:26:00 -0700838 int pages_moved = 0;
Mel Gormanc361be52007-10-16 01:25:51 -0700839
840#ifndef CONFIG_HOLES_IN_ZONE
841 /*
842 * page_zone is not safe to call in this context when
843 * CONFIG_HOLES_IN_ZONE is set. This bug check is probably redundant
844 * anyway as we check zone boundaries in move_freepages_block().
845 * Remove at a later date when no bug reports exist related to
Mel Gormanac0e5b72007-10-16 01:25:58 -0700846 * grouping pages by mobility
Mel Gormanc361be52007-10-16 01:25:51 -0700847 */
848 BUG_ON(page_zone(start_page) != page_zone(end_page));
849#endif
850
851 for (page = start_page; page <= end_page;) {
Adam Litke344c7902008-09-02 14:35:38 -0700852 /* Make sure we are not inadvertently changing nodes */
853 VM_BUG_ON(page_to_nid(page) != zone_to_nid(zone));
854
Mel Gormanc361be52007-10-16 01:25:51 -0700855 if (!pfn_valid_within(page_to_pfn(page))) {
856 page++;
857 continue;
858 }
859
860 if (!PageBuddy(page)) {
861 page++;
862 continue;
863 }
864
865 order = page_order(page);
866 list_del(&page->lru);
867 list_add(&page->lru,
868 &zone->free_area[order].free_list[migratetype]);
869 page += 1 << order;
Mel Gormand1003132007-10-16 01:26:00 -0700870 pages_moved += 1 << order;
Mel Gormanc361be52007-10-16 01:25:51 -0700871 }
872
Mel Gormand1003132007-10-16 01:26:00 -0700873 return pages_moved;
Mel Gormanc361be52007-10-16 01:25:51 -0700874}
875
Adrian Bunkb69a7282008-07-23 21:28:12 -0700876static int move_freepages_block(struct zone *zone, struct page *page,
877 int migratetype)
Mel Gormanc361be52007-10-16 01:25:51 -0700878{
879 unsigned long start_pfn, end_pfn;
880 struct page *start_page, *end_page;
881
882 start_pfn = page_to_pfn(page);
Mel Gormand9c23402007-10-16 01:26:01 -0700883 start_pfn = start_pfn & ~(pageblock_nr_pages-1);
Mel Gormanc361be52007-10-16 01:25:51 -0700884 start_page = pfn_to_page(start_pfn);
Mel Gormand9c23402007-10-16 01:26:01 -0700885 end_page = start_page + pageblock_nr_pages - 1;
886 end_pfn = start_pfn + pageblock_nr_pages - 1;
Mel Gormanc361be52007-10-16 01:25:51 -0700887
888 /* Do not cross zone boundaries */
889 if (start_pfn < zone->zone_start_pfn)
890 start_page = page;
891 if (end_pfn >= zone->zone_start_pfn + zone->spanned_pages)
892 return 0;
893
894 return move_freepages(zone, start_page, end_page, migratetype);
895}
896
Mel Gorman2f66a682009-09-21 17:02:31 -0700897static void change_pageblock_range(struct page *pageblock_page,
898 int start_order, int migratetype)
899{
900 int nr_pageblocks = 1 << (start_order - pageblock_order);
901
902 while (nr_pageblocks--) {
903 set_pageblock_migratetype(pageblock_page, migratetype);
904 pageblock_page += pageblock_nr_pages;
905 }
906}
907
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700908/* Remove an element from the buddy allocator from the fallback list */
Mel Gorman0ac3a402009-06-16 15:32:06 -0700909static inline struct page *
910__rmqueue_fallback(struct zone *zone, int order, int start_migratetype)
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700911{
912 struct free_area * area;
913 int current_order;
914 struct page *page;
915 int migratetype, i;
916
917 /* Find the largest possible block of pages in the other list */
918 for (current_order = MAX_ORDER-1; current_order >= order;
919 --current_order) {
920 for (i = 0; i < MIGRATE_TYPES - 1; i++) {
921 migratetype = fallbacks[start_migratetype][i];
922
Mel Gorman56fd56b2007-10-16 01:25:58 -0700923 /* MIGRATE_RESERVE handled later if necessary */
924 if (migratetype == MIGRATE_RESERVE)
925 continue;
Mel Gormane0104872007-10-16 01:25:53 -0700926
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700927 area = &(zone->free_area[current_order]);
928 if (list_empty(&area->free_list[migratetype]))
929 continue;
930
931 page = list_entry(area->free_list[migratetype].next,
932 struct page, lru);
933 area->nr_free--;
934
935 /*
Mel Gormanc361be52007-10-16 01:25:51 -0700936 * If breaking a large block of pages, move all free
Mel Gorman46dafbc2007-10-16 01:25:55 -0700937 * pages to the preferred allocation list. If falling
938 * back for a reclaimable kernel allocation, be more
939 * agressive about taking ownership of free pages
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700940 */
Mel Gormand9c23402007-10-16 01:26:01 -0700941 if (unlikely(current_order >= (pageblock_order >> 1)) ||
Mel Gormandd5d2412009-09-05 11:17:11 -0700942 start_migratetype == MIGRATE_RECLAIMABLE ||
943 page_group_by_mobility_disabled) {
Mel Gorman46dafbc2007-10-16 01:25:55 -0700944 unsigned long pages;
945 pages = move_freepages_block(zone, page,
946 start_migratetype);
947
948 /* Claim the whole block if over half of it is free */
Mel Gormandd5d2412009-09-05 11:17:11 -0700949 if (pages >= (1 << (pageblock_order-1)) ||
950 page_group_by_mobility_disabled)
Mel Gorman46dafbc2007-10-16 01:25:55 -0700951 set_pageblock_migratetype(page,
952 start_migratetype);
953
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700954 migratetype = start_migratetype;
Mel Gormanc361be52007-10-16 01:25:51 -0700955 }
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700956
957 /* Remove the page from the freelists */
958 list_del(&page->lru);
959 rmv_page_order(page);
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700960
Mel Gorman2f66a682009-09-21 17:02:31 -0700961 /* Take ownership for orders >= pageblock_order */
962 if (current_order >= pageblock_order)
963 change_pageblock_range(page, current_order,
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700964 start_migratetype);
965
966 expand(zone, page, order, current_order, area, migratetype);
Mel Gormane0fff1b2009-09-21 17:02:42 -0700967
968 trace_mm_page_alloc_extfrag(page, order, current_order,
969 start_migratetype, migratetype);
970
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700971 return page;
972 }
973 }
974
Mel Gorman728ec982009-06-16 15:32:04 -0700975 return NULL;
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700976}
977
Mel Gorman56fd56b2007-10-16 01:25:58 -0700978/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700979 * Do the hard work of removing an element from the buddy allocator.
980 * Call me with the zone->lock already held.
981 */
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700982static struct page *__rmqueue(struct zone *zone, unsigned int order,
983 int migratetype)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700984{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700985 struct page *page;
986
Mel Gorman728ec982009-06-16 15:32:04 -0700987retry_reserve:
Mel Gorman56fd56b2007-10-16 01:25:58 -0700988 page = __rmqueue_smallest(zone, order, migratetype);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700989
Mel Gorman728ec982009-06-16 15:32:04 -0700990 if (unlikely(!page) && migratetype != MIGRATE_RESERVE) {
Mel Gorman56fd56b2007-10-16 01:25:58 -0700991 page = __rmqueue_fallback(zone, order, migratetype);
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700992
Mel Gorman728ec982009-06-16 15:32:04 -0700993 /*
994 * Use MIGRATE_RESERVE rather than fail an allocation. goto
995 * is used because __rmqueue_smallest is an inline function
996 * and we want just one call site
997 */
998 if (!page) {
999 migratetype = MIGRATE_RESERVE;
1000 goto retry_reserve;
1001 }
1002 }
1003
Mel Gorman0d3d0622009-09-21 17:02:44 -07001004 trace_mm_page_alloc_zone_locked(page, order, migratetype);
Mel Gormanb2a0ac82007-10-16 01:25:48 -07001005 return page;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001006}
1007
1008/*
1009 * Obtain a specified number of elements from the buddy allocator, all under
1010 * a single hold of the lock, for efficiency. Add them to the supplied list.
1011 * Returns the number of new pages which were placed at *list.
1012 */
1013static int rmqueue_bulk(struct zone *zone, unsigned int order,
Mel Gormanb2a0ac82007-10-16 01:25:48 -07001014 unsigned long count, struct list_head *list,
Mel Gormane084b2d2009-07-29 15:02:04 -07001015 int migratetype, int cold)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001016{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001017 int i;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001018
Nick Pigginc54ad302006-01-06 00:10:56 -08001019 spin_lock(&zone->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001020 for (i = 0; i < count; ++i) {
Mel Gormanb2a0ac82007-10-16 01:25:48 -07001021 struct page *page = __rmqueue(zone, order, migratetype);
Nick Piggin085cc7d2006-01-06 00:11:01 -08001022 if (unlikely(page == NULL))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001023 break;
Mel Gorman81eabcb2007-12-17 16:20:05 -08001024
1025 /*
1026 * Split buddy pages returned by expand() are received here
1027 * in physical page order. The page is added to the callers and
1028 * list and the list head then moves forward. From the callers
1029 * perspective, the linked list is ordered by page number in
1030 * some conditions. This is useful for IO devices that can
1031 * merge IO requests if the physical pages are ordered
1032 * properly.
1033 */
Mel Gormane084b2d2009-07-29 15:02:04 -07001034 if (likely(cold == 0))
1035 list_add(&page->lru, list);
1036 else
1037 list_add_tail(&page->lru, list);
Mel Gorman535131e2007-10-16 01:25:49 -07001038 set_page_private(page, migratetype);
Mel Gorman81eabcb2007-12-17 16:20:05 -08001039 list = &page->lru;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001040 }
Mel Gormanf2260e62009-06-16 15:32:13 -07001041 __mod_zone_page_state(zone, NR_FREE_PAGES, -(i << order));
Nick Pigginc54ad302006-01-06 00:10:56 -08001042 spin_unlock(&zone->lock);
Nick Piggin085cc7d2006-01-06 00:11:01 -08001043 return i;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001044}
1045
Christoph Lameter4ae7c032005-06-21 17:14:57 -07001046#ifdef CONFIG_NUMA
Christoph Lameter8fce4d82006-03-09 17:33:54 -08001047/*
Christoph Lameter4037d452007-05-09 02:35:14 -07001048 * Called from the vmstat counter updater to drain pagesets of this
1049 * currently executing processor on remote nodes after they have
1050 * expired.
1051 *
Christoph Lameter879336c2006-03-22 00:09:08 -08001052 * Note that this function must be called with the thread pinned to
1053 * a single processor.
Christoph Lameter8fce4d82006-03-09 17:33:54 -08001054 */
Christoph Lameter4037d452007-05-09 02:35:14 -07001055void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp)
Christoph Lameter4ae7c032005-06-21 17:14:57 -07001056{
Christoph Lameter4ae7c032005-06-21 17:14:57 -07001057 unsigned long flags;
Christoph Lameter4037d452007-05-09 02:35:14 -07001058 int to_drain;
Christoph Lameter4ae7c032005-06-21 17:14:57 -07001059
Christoph Lameter4037d452007-05-09 02:35:14 -07001060 local_irq_save(flags);
1061 if (pcp->count >= pcp->batch)
1062 to_drain = pcp->batch;
1063 else
1064 to_drain = pcp->count;
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001065 free_pcppages_bulk(zone, to_drain, pcp);
Christoph Lameter4037d452007-05-09 02:35:14 -07001066 pcp->count -= to_drain;
1067 local_irq_restore(flags);
Christoph Lameter4ae7c032005-06-21 17:14:57 -07001068}
1069#endif
1070
Christoph Lameter9f8f2172008-02-04 22:29:11 -08001071/*
1072 * Drain pages of the indicated processor.
1073 *
1074 * The processor must either be the current processor and the
1075 * thread pinned to the current processor or a processor that
1076 * is not online.
1077 */
1078static void drain_pages(unsigned int cpu)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001079{
Nick Pigginc54ad302006-01-06 00:10:56 -08001080 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001081 struct zone *zone;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001082
KOSAKI Motohiroee99c712009-03-31 15:19:31 -07001083 for_each_populated_zone(zone) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001084 struct per_cpu_pageset *pset;
Christoph Lameter3dfa5722008-02-04 22:29:19 -08001085 struct per_cpu_pages *pcp;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001086
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09001087 local_irq_save(flags);
1088 pset = per_cpu_ptr(zone->pageset, cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001089
Christoph Lameter3dfa5722008-02-04 22:29:19 -08001090 pcp = &pset->pcp;
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001091 free_pcppages_bulk(zone, pcp->count, pcp);
Christoph Lameter3dfa5722008-02-04 22:29:19 -08001092 pcp->count = 0;
1093 local_irq_restore(flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001094 }
1095}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001096
Christoph Lameter9f8f2172008-02-04 22:29:11 -08001097/*
1098 * Spill all of this CPU's per-cpu pages back into the buddy allocator.
1099 */
1100void drain_local_pages(void *arg)
1101{
1102 drain_pages(smp_processor_id());
1103}
1104
1105/*
1106 * Spill all the per-cpu pages from all CPUs back into the buddy allocator
1107 */
1108void drain_all_pages(void)
1109{
Jens Axboe15c8b6c2008-05-09 09:39:44 +02001110 on_each_cpu(drain_local_pages, NULL, 1);
Christoph Lameter9f8f2172008-02-04 22:29:11 -08001111}
1112
Rafael J. Wysocki296699d2007-07-29 23:27:18 +02001113#ifdef CONFIG_HIBERNATION
Linus Torvalds1da177e2005-04-16 15:20:36 -07001114
1115void mark_free_pages(struct zone *zone)
1116{
Rafael J. Wysockif623f0d2006-09-25 23:32:49 -07001117 unsigned long pfn, max_zone_pfn;
1118 unsigned long flags;
Mel Gormanb2a0ac82007-10-16 01:25:48 -07001119 int order, t;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001120 struct list_head *curr;
1121
1122 if (!zone->spanned_pages)
1123 return;
1124
1125 spin_lock_irqsave(&zone->lock, flags);
Rafael J. Wysockif623f0d2006-09-25 23:32:49 -07001126
1127 max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
1128 for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
1129 if (pfn_valid(pfn)) {
1130 struct page *page = pfn_to_page(pfn);
1131
Rafael J. Wysocki7be98232007-05-06 14:50:42 -07001132 if (!swsusp_page_is_forbidden(page))
1133 swsusp_unset_page_free(page);
Rafael J. Wysockif623f0d2006-09-25 23:32:49 -07001134 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001135
Mel Gormanb2a0ac82007-10-16 01:25:48 -07001136 for_each_migratetype_order(order, t) {
1137 list_for_each(curr, &zone->free_area[order].free_list[t]) {
Rafael J. Wysockif623f0d2006-09-25 23:32:49 -07001138 unsigned long i;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001139
Rafael J. Wysockif623f0d2006-09-25 23:32:49 -07001140 pfn = page_to_pfn(list_entry(curr, struct page, lru));
1141 for (i = 0; i < (1UL << order); i++)
Rafael J. Wysocki7be98232007-05-06 14:50:42 -07001142 swsusp_set_page_free(pfn_to_page(pfn + i));
Rafael J. Wysockif623f0d2006-09-25 23:32:49 -07001143 }
Mel Gormanb2a0ac82007-10-16 01:25:48 -07001144 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001145 spin_unlock_irqrestore(&zone->lock, flags);
1146}
Mel Gormane2c55dc2007-10-16 01:25:50 -07001147#endif /* CONFIG_PM */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001148
1149/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07001150 * Free a 0-order page
Li Hongfc916682010-03-05 13:41:54 -08001151 * cold == 1 ? free a cold page : free a hot page
Linus Torvalds1da177e2005-04-16 15:20:36 -07001152 */
Li Hongfc916682010-03-05 13:41:54 -08001153void free_hot_cold_page(struct page *page, int cold)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001154{
1155 struct zone *zone = page_zone(page);
1156 struct per_cpu_pages *pcp;
1157 unsigned long flags;
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001158 int migratetype;
Johannes Weiner451ea252009-09-21 17:01:48 -07001159 int wasMlocked = __TestClearPageMlocked(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001160
KOSAKI Motohiroec95f532010-05-24 14:32:38 -07001161 if (!free_pages_prepare(page, 0))
Hugh Dickins689bceb2005-11-21 21:32:20 -08001162 return;
1163
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001164 migratetype = get_pageblock_migratetype(page);
1165 set_page_private(page, migratetype);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001166 local_irq_save(flags);
Johannes Weinerc2773312009-06-19 19:30:56 +02001167 if (unlikely(wasMlocked))
Mel Gormanda456f12009-06-16 15:32:08 -07001168 free_page_mlock(page);
Christoph Lameterf8891e52006-06-30 01:55:45 -07001169 __count_vm_event(PGFREE);
Mel Gormanda456f12009-06-16 15:32:08 -07001170
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001171 /*
1172 * We only track unmovable, reclaimable and movable on pcp lists.
1173 * Free ISOLATE pages back to the allocator because they are being
1174 * offlined but treat RESERVE as movable pages so we can get those
1175 * areas back if necessary. Otherwise, we may have to free
1176 * excessively into the page allocator
1177 */
1178 if (migratetype >= MIGRATE_PCPTYPES) {
1179 if (unlikely(migratetype == MIGRATE_ISOLATE)) {
1180 free_one_page(zone, page, 0, migratetype);
1181 goto out;
1182 }
1183 migratetype = MIGRATE_MOVABLE;
1184 }
1185
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09001186 pcp = &this_cpu_ptr(zone->pageset)->pcp;
Christoph Lameter3dfa5722008-02-04 22:29:19 -08001187 if (cold)
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001188 list_add_tail(&page->lru, &pcp->lists[migratetype]);
Christoph Lameter3dfa5722008-02-04 22:29:19 -08001189 else
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001190 list_add(&page->lru, &pcp->lists[migratetype]);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001191 pcp->count++;
Nick Piggin48db57f2006-01-08 01:00:42 -08001192 if (pcp->count >= pcp->high) {
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001193 free_pcppages_bulk(zone, pcp->batch, pcp);
Nick Piggin48db57f2006-01-08 01:00:42 -08001194 pcp->count -= pcp->batch;
1195 }
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001196
1197out:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001198 local_irq_restore(flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001199}
1200
Nick Piggin8dfcc9b2006-03-22 00:08:05 -08001201/*
1202 * split_page takes a non-compound higher-order page, and splits it into
1203 * n (1<<order) sub-pages: page[0..n]
1204 * Each sub-page must be freed individually.
1205 *
1206 * Note: this is probably too low level an operation for use in drivers.
1207 * Please consult with lkml before using this in your driver.
1208 */
1209void split_page(struct page *page, unsigned int order)
1210{
1211 int i;
1212
Nick Piggin725d7042006-09-25 23:30:55 -07001213 VM_BUG_ON(PageCompound(page));
1214 VM_BUG_ON(!page_count(page));
Vegard Nossumb1eeab62008-11-25 16:55:53 +01001215
1216#ifdef CONFIG_KMEMCHECK
1217 /*
1218 * Split shadow pages too, because free(page[0]) would
1219 * otherwise free the whole shadow.
1220 */
1221 if (kmemcheck_page_is_tracked(page))
1222 split_page(virt_to_page(page[0].shadow), order);
1223#endif
1224
Nick Piggin7835e982006-03-22 00:08:40 -08001225 for (i = 1; i < (1 << order); i++)
1226 set_page_refcounted(page + i);
Nick Piggin8dfcc9b2006-03-22 00:08:05 -08001227}
Nick Piggin8dfcc9b2006-03-22 00:08:05 -08001228
Linus Torvalds1da177e2005-04-16 15:20:36 -07001229/*
Mel Gorman748446b2010-05-24 14:32:27 -07001230 * Similar to split_page except the page is already free. As this is only
1231 * being used for migration, the migratetype of the block also changes.
1232 * As this is called with interrupts disabled, the caller is responsible
1233 * for calling arch_alloc_page() and kernel_map_page() after interrupts
1234 * are enabled.
1235 *
1236 * Note: this is probably too low level an operation for use in drivers.
1237 * Please consult with lkml before using this in your driver.
1238 */
1239int split_free_page(struct page *page)
1240{
1241 unsigned int order;
1242 unsigned long watermark;
1243 struct zone *zone;
1244
1245 BUG_ON(!PageBuddy(page));
1246
1247 zone = page_zone(page);
1248 order = page_order(page);
1249
1250 /* Obey watermarks as if the page was being allocated */
1251 watermark = low_wmark_pages(zone) + (1 << order);
1252 if (!zone_watermark_ok(zone, 0, watermark, 0, 0))
1253 return 0;
1254
1255 /* Remove page from free list */
1256 list_del(&page->lru);
1257 zone->free_area[order].nr_free--;
1258 rmv_page_order(page);
1259 __mod_zone_page_state(zone, NR_FREE_PAGES, -(1UL << order));
1260
1261 /* Split into individual pages */
1262 set_page_refcounted(page);
1263 split_page(page, order);
1264
1265 if (order >= pageblock_order - 1) {
1266 struct page *endpage = page + (1 << order) - 1;
1267 for (; page < endpage; page += pageblock_nr_pages)
1268 set_pageblock_migratetype(page, MIGRATE_MOVABLE);
1269 }
1270
1271 return 1 << order;
1272}
1273
1274/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07001275 * Really, prep_compound_page() should be called from __rmqueue_bulk(). But
1276 * we cheat by calling it from here, in the order > 0 path. Saves a branch
1277 * or two.
1278 */
Mel Gorman0a15c3e2009-06-16 15:32:05 -07001279static inline
1280struct page *buffered_rmqueue(struct zone *preferred_zone,
Mel Gorman3dd28262009-06-16 15:32:00 -07001281 struct zone *zone, int order, gfp_t gfp_flags,
1282 int migratetype)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001283{
1284 unsigned long flags;
Hugh Dickins689bceb2005-11-21 21:32:20 -08001285 struct page *page;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001286 int cold = !!(gfp_flags & __GFP_COLD);
1287
Hugh Dickins689bceb2005-11-21 21:32:20 -08001288again:
Nick Piggin48db57f2006-01-08 01:00:42 -08001289 if (likely(order == 0)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001290 struct per_cpu_pages *pcp;
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001291 struct list_head *list;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001292
Linus Torvalds1da177e2005-04-16 15:20:36 -07001293 local_irq_save(flags);
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09001294 pcp = &this_cpu_ptr(zone->pageset)->pcp;
1295 list = &pcp->lists[migratetype];
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001296 if (list_empty(list)) {
Mel Gorman535131e2007-10-16 01:25:49 -07001297 pcp->count += rmqueue_bulk(zone, 0,
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001298 pcp->batch, list,
Mel Gormane084b2d2009-07-29 15:02:04 -07001299 migratetype, cold);
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001300 if (unlikely(list_empty(list)))
Shaohua Li6fb332f2009-09-21 17:01:17 -07001301 goto failed;
Mel Gorman535131e2007-10-16 01:25:49 -07001302 }
Mel Gormanb92a6ed2007-10-16 01:25:50 -07001303
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001304 if (cold)
1305 page = list_entry(list->prev, struct page, lru);
1306 else
1307 page = list_entry(list->next, struct page, lru);
1308
Mel Gormanb92a6ed2007-10-16 01:25:50 -07001309 list_del(&page->lru);
1310 pcp->count--;
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001311 } else {
Andrew Mortondab48da2009-06-16 15:32:37 -07001312 if (unlikely(gfp_flags & __GFP_NOFAIL)) {
1313 /*
1314 * __GFP_NOFAIL is not to be used in new code.
1315 *
1316 * All __GFP_NOFAIL callers should be fixed so that they
1317 * properly detect and handle allocation failures.
1318 *
1319 * We most definitely don't want callers attempting to
Linus Torvalds4923abf2009-06-24 12:16:49 -07001320 * allocate greater than order-1 page units with
Andrew Mortondab48da2009-06-16 15:32:37 -07001321 * __GFP_NOFAIL.
1322 */
Linus Torvalds4923abf2009-06-24 12:16:49 -07001323 WARN_ON_ONCE(order > 1);
Andrew Mortondab48da2009-06-16 15:32:37 -07001324 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001325 spin_lock_irqsave(&zone->lock, flags);
Mel Gormanb2a0ac82007-10-16 01:25:48 -07001326 page = __rmqueue(zone, order, migratetype);
Nick Piggina74609f2006-01-06 00:11:20 -08001327 spin_unlock(&zone->lock);
1328 if (!page)
1329 goto failed;
KOSAKI Motohiro6ccf80e2010-01-15 17:01:18 -08001330 __mod_zone_page_state(zone, NR_FREE_PAGES, -(1 << order));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001331 }
1332
Christoph Lameterf8891e52006-06-30 01:55:45 -07001333 __count_zone_vm_events(PGALLOC, zone, 1 << order);
Mel Gorman18ea7e72008-04-28 02:12:14 -07001334 zone_statistics(preferred_zone, zone);
Nick Piggina74609f2006-01-06 00:11:20 -08001335 local_irq_restore(flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001336
Nick Piggin725d7042006-09-25 23:30:55 -07001337 VM_BUG_ON(bad_range(zone, page));
Nick Piggin17cf4402006-03-22 00:08:41 -08001338 if (prep_new_page(page, order, gfp_flags))
Nick Piggina74609f2006-01-06 00:11:20 -08001339 goto again;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001340 return page;
Nick Piggina74609f2006-01-06 00:11:20 -08001341
1342failed:
1343 local_irq_restore(flags);
Nick Piggina74609f2006-01-06 00:11:20 -08001344 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001345}
1346
Mel Gorman41858962009-06-16 15:32:12 -07001347/* The ALLOC_WMARK bits are used as an index to zone->watermark */
1348#define ALLOC_WMARK_MIN WMARK_MIN
1349#define ALLOC_WMARK_LOW WMARK_LOW
1350#define ALLOC_WMARK_HIGH WMARK_HIGH
1351#define ALLOC_NO_WATERMARKS 0x04 /* don't check watermarks at all */
1352
1353/* Mask to get the watermark bits */
1354#define ALLOC_WMARK_MASK (ALLOC_NO_WATERMARKS-1)
1355
Nick Piggin31488902005-11-28 13:44:03 -08001356#define ALLOC_HARDER 0x10 /* try to alloc harder */
1357#define ALLOC_HIGH 0x20 /* __GFP_HIGH set */
1358#define ALLOC_CPUSET 0x40 /* check for correct cpuset */
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001359
Akinobu Mita933e3122006-12-08 02:39:45 -08001360#ifdef CONFIG_FAIL_PAGE_ALLOC
1361
1362static struct fail_page_alloc_attr {
1363 struct fault_attr attr;
1364
1365 u32 ignore_gfp_highmem;
1366 u32 ignore_gfp_wait;
Akinobu Mita54114992007-07-15 23:40:23 -07001367 u32 min_order;
Akinobu Mita933e3122006-12-08 02:39:45 -08001368
1369#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
1370
1371 struct dentry *ignore_gfp_highmem_file;
1372 struct dentry *ignore_gfp_wait_file;
Akinobu Mita54114992007-07-15 23:40:23 -07001373 struct dentry *min_order_file;
Akinobu Mita933e3122006-12-08 02:39:45 -08001374
1375#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
1376
1377} fail_page_alloc = {
1378 .attr = FAULT_ATTR_INITIALIZER,
Don Mullis6b1b60f2006-12-08 02:39:53 -08001379 .ignore_gfp_wait = 1,
1380 .ignore_gfp_highmem = 1,
Akinobu Mita54114992007-07-15 23:40:23 -07001381 .min_order = 1,
Akinobu Mita933e3122006-12-08 02:39:45 -08001382};
1383
1384static int __init setup_fail_page_alloc(char *str)
1385{
1386 return setup_fault_attr(&fail_page_alloc.attr, str);
1387}
1388__setup("fail_page_alloc=", setup_fail_page_alloc);
1389
1390static int should_fail_alloc_page(gfp_t gfp_mask, unsigned int order)
1391{
Akinobu Mita54114992007-07-15 23:40:23 -07001392 if (order < fail_page_alloc.min_order)
1393 return 0;
Akinobu Mita933e3122006-12-08 02:39:45 -08001394 if (gfp_mask & __GFP_NOFAIL)
1395 return 0;
1396 if (fail_page_alloc.ignore_gfp_highmem && (gfp_mask & __GFP_HIGHMEM))
1397 return 0;
1398 if (fail_page_alloc.ignore_gfp_wait && (gfp_mask & __GFP_WAIT))
1399 return 0;
1400
1401 return should_fail(&fail_page_alloc.attr, 1 << order);
1402}
1403
1404#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
1405
1406static int __init fail_page_alloc_debugfs(void)
1407{
1408 mode_t mode = S_IFREG | S_IRUSR | S_IWUSR;
1409 struct dentry *dir;
1410 int err;
1411
1412 err = init_fault_attr_dentries(&fail_page_alloc.attr,
1413 "fail_page_alloc");
1414 if (err)
1415 return err;
1416 dir = fail_page_alloc.attr.dentries.dir;
1417
1418 fail_page_alloc.ignore_gfp_wait_file =
1419 debugfs_create_bool("ignore-gfp-wait", mode, dir,
1420 &fail_page_alloc.ignore_gfp_wait);
1421
1422 fail_page_alloc.ignore_gfp_highmem_file =
1423 debugfs_create_bool("ignore-gfp-highmem", mode, dir,
1424 &fail_page_alloc.ignore_gfp_highmem);
Akinobu Mita54114992007-07-15 23:40:23 -07001425 fail_page_alloc.min_order_file =
1426 debugfs_create_u32("min-order", mode, dir,
1427 &fail_page_alloc.min_order);
Akinobu Mita933e3122006-12-08 02:39:45 -08001428
1429 if (!fail_page_alloc.ignore_gfp_wait_file ||
Akinobu Mita54114992007-07-15 23:40:23 -07001430 !fail_page_alloc.ignore_gfp_highmem_file ||
1431 !fail_page_alloc.min_order_file) {
Akinobu Mita933e3122006-12-08 02:39:45 -08001432 err = -ENOMEM;
1433 debugfs_remove(fail_page_alloc.ignore_gfp_wait_file);
1434 debugfs_remove(fail_page_alloc.ignore_gfp_highmem_file);
Akinobu Mita54114992007-07-15 23:40:23 -07001435 debugfs_remove(fail_page_alloc.min_order_file);
Akinobu Mita933e3122006-12-08 02:39:45 -08001436 cleanup_fault_attr_dentries(&fail_page_alloc.attr);
1437 }
1438
1439 return err;
1440}
1441
1442late_initcall(fail_page_alloc_debugfs);
1443
1444#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
1445
1446#else /* CONFIG_FAIL_PAGE_ALLOC */
1447
1448static inline int should_fail_alloc_page(gfp_t gfp_mask, unsigned int order)
1449{
1450 return 0;
1451}
1452
1453#endif /* CONFIG_FAIL_PAGE_ALLOC */
1454
Linus Torvalds1da177e2005-04-16 15:20:36 -07001455/*
Mel Gorman88f5acf2011-01-13 15:45:41 -08001456 * Return true if free pages are above 'mark'. This takes into account the order
Linus Torvalds1da177e2005-04-16 15:20:36 -07001457 * of the allocation.
1458 */
Mel Gorman88f5acf2011-01-13 15:45:41 -08001459static bool __zone_watermark_ok(struct zone *z, int order, unsigned long mark,
1460 int classzone_idx, int alloc_flags, long free_pages)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001461{
1462 /* free_pages my go negative - that's OK */
Christoph Lameterd23ad422007-02-10 01:43:02 -08001463 long min = mark;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001464 int o;
1465
Mel Gorman88f5acf2011-01-13 15:45:41 -08001466 free_pages -= (1 << order) + 1;
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001467 if (alloc_flags & ALLOC_HIGH)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001468 min -= min / 2;
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001469 if (alloc_flags & ALLOC_HARDER)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001470 min -= min / 4;
1471
1472 if (free_pages <= min + z->lowmem_reserve[classzone_idx])
Mel Gorman88f5acf2011-01-13 15:45:41 -08001473 return false;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001474 for (o = 0; o < order; o++) {
1475 /* At the next order, this order's pages become unavailable */
1476 free_pages -= z->free_area[o].nr_free << o;
1477
1478 /* Require fewer higher order pages to be free */
1479 min >>= 1;
1480
1481 if (free_pages <= min)
Mel Gorman88f5acf2011-01-13 15:45:41 -08001482 return false;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001483 }
Mel Gorman88f5acf2011-01-13 15:45:41 -08001484 return true;
1485}
1486
1487bool zone_watermark_ok(struct zone *z, int order, unsigned long mark,
1488 int classzone_idx, int alloc_flags)
1489{
1490 return __zone_watermark_ok(z, order, mark, classzone_idx, alloc_flags,
1491 zone_page_state(z, NR_FREE_PAGES));
1492}
1493
1494bool zone_watermark_ok_safe(struct zone *z, int order, unsigned long mark,
1495 int classzone_idx, int alloc_flags)
1496{
1497 long free_pages = zone_page_state(z, NR_FREE_PAGES);
1498
1499 if (z->percpu_drift_mark && free_pages < z->percpu_drift_mark)
1500 free_pages = zone_page_state_snapshot(z, NR_FREE_PAGES);
1501
1502 return __zone_watermark_ok(z, order, mark, classzone_idx, alloc_flags,
1503 free_pages);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001504}
1505
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001506#ifdef CONFIG_NUMA
1507/*
1508 * zlc_setup - Setup for "zonelist cache". Uses cached zone data to
1509 * skip over zones that are not allowed by the cpuset, or that have
1510 * been recently (in last second) found to be nearly full. See further
1511 * comments in mmzone.h. Reduces cache footprint of zonelist scans
Simon Arlott183ff222007-10-20 01:27:18 +02001512 * that have to skip over a lot of full or unallowed zones.
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001513 *
1514 * If the zonelist cache is present in the passed in zonelist, then
1515 * returns a pointer to the allowed node mask (either the current
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07001516 * tasks mems_allowed, or node_states[N_HIGH_MEMORY].)
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001517 *
1518 * If the zonelist cache is not available for this zonelist, does
1519 * nothing and returns NULL.
1520 *
1521 * If the fullzones BITMAP in the zonelist cache is stale (more than
1522 * a second since last zap'd) then we zap it out (clear its bits.)
1523 *
1524 * We hold off even calling zlc_setup, until after we've checked the
1525 * first zone in the zonelist, on the theory that most allocations will
1526 * be satisfied from that first zone, so best to examine that zone as
1527 * quickly as we can.
1528 */
1529static nodemask_t *zlc_setup(struct zonelist *zonelist, int alloc_flags)
1530{
1531 struct zonelist_cache *zlc; /* cached zonelist speedup info */
1532 nodemask_t *allowednodes; /* zonelist_cache approximation */
1533
1534 zlc = zonelist->zlcache_ptr;
1535 if (!zlc)
1536 return NULL;
1537
S.Caglar Onurf05111f2008-04-28 02:12:38 -07001538 if (time_after(jiffies, zlc->last_full_zap + HZ)) {
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001539 bitmap_zero(zlc->fullzones, MAX_ZONES_PER_ZONELIST);
1540 zlc->last_full_zap = jiffies;
1541 }
1542
1543 allowednodes = !in_interrupt() && (alloc_flags & ALLOC_CPUSET) ?
1544 &cpuset_current_mems_allowed :
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07001545 &node_states[N_HIGH_MEMORY];
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001546 return allowednodes;
1547}
1548
1549/*
1550 * Given 'z' scanning a zonelist, run a couple of quick checks to see
1551 * if it is worth looking at further for free memory:
1552 * 1) Check that the zone isn't thought to be full (doesn't have its
1553 * bit set in the zonelist_cache fullzones BITMAP).
1554 * 2) Check that the zones node (obtained from the zonelist_cache
1555 * z_to_n[] mapping) is allowed in the passed in allowednodes mask.
1556 * Return true (non-zero) if zone is worth looking at further, or
1557 * else return false (zero) if it is not.
1558 *
1559 * This check -ignores- the distinction between various watermarks,
1560 * such as GFP_HIGH, GFP_ATOMIC, PF_MEMALLOC, ... If a zone is
1561 * found to be full for any variation of these watermarks, it will
1562 * be considered full for up to one second by all requests, unless
1563 * we are so low on memory on all allowed nodes that we are forced
1564 * into the second scan of the zonelist.
1565 *
1566 * In the second scan we ignore this zonelist cache and exactly
1567 * apply the watermarks to all zones, even it is slower to do so.
1568 * We are low on memory in the second scan, and should leave no stone
1569 * unturned looking for a free page.
1570 */
Mel Gormandd1a2392008-04-28 02:12:17 -07001571static int zlc_zone_worth_trying(struct zonelist *zonelist, struct zoneref *z,
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001572 nodemask_t *allowednodes)
1573{
1574 struct zonelist_cache *zlc; /* cached zonelist speedup info */
1575 int i; /* index of *z in zonelist zones */
1576 int n; /* node that zone *z is on */
1577
1578 zlc = zonelist->zlcache_ptr;
1579 if (!zlc)
1580 return 1;
1581
Mel Gormandd1a2392008-04-28 02:12:17 -07001582 i = z - zonelist->_zonerefs;
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001583 n = zlc->z_to_n[i];
1584
1585 /* This zone is worth trying if it is allowed but not full */
1586 return node_isset(n, *allowednodes) && !test_bit(i, zlc->fullzones);
1587}
1588
1589/*
1590 * Given 'z' scanning a zonelist, set the corresponding bit in
1591 * zlc->fullzones, so that subsequent attempts to allocate a page
1592 * from that zone don't waste time re-examining it.
1593 */
Mel Gormandd1a2392008-04-28 02:12:17 -07001594static void zlc_mark_zone_full(struct zonelist *zonelist, struct zoneref *z)
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001595{
1596 struct zonelist_cache *zlc; /* cached zonelist speedup info */
1597 int i; /* index of *z in zonelist zones */
1598
1599 zlc = zonelist->zlcache_ptr;
1600 if (!zlc)
1601 return;
1602
Mel Gormandd1a2392008-04-28 02:12:17 -07001603 i = z - zonelist->_zonerefs;
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001604
1605 set_bit(i, zlc->fullzones);
1606}
1607
1608#else /* CONFIG_NUMA */
1609
1610static nodemask_t *zlc_setup(struct zonelist *zonelist, int alloc_flags)
1611{
1612 return NULL;
1613}
1614
Mel Gormandd1a2392008-04-28 02:12:17 -07001615static int zlc_zone_worth_trying(struct zonelist *zonelist, struct zoneref *z,
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001616 nodemask_t *allowednodes)
1617{
1618 return 1;
1619}
1620
Mel Gormandd1a2392008-04-28 02:12:17 -07001621static void zlc_mark_zone_full(struct zonelist *zonelist, struct zoneref *z)
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001622{
1623}
1624#endif /* CONFIG_NUMA */
1625
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001626/*
Paul Jackson0798e512006-12-06 20:31:38 -08001627 * get_page_from_freelist goes through the zonelist trying to allocate
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001628 * a page.
1629 */
1630static struct page *
Mel Gorman19770b32008-04-28 02:12:18 -07001631get_page_from_freelist(gfp_t gfp_mask, nodemask_t *nodemask, unsigned int order,
Mel Gorman5117f452009-06-16 15:31:59 -07001632 struct zonelist *zonelist, int high_zoneidx, int alloc_flags,
Mel Gorman3dd28262009-06-16 15:32:00 -07001633 struct zone *preferred_zone, int migratetype)
Martin Hicks753ee722005-06-21 17:14:41 -07001634{
Mel Gormandd1a2392008-04-28 02:12:17 -07001635 struct zoneref *z;
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001636 struct page *page = NULL;
Mel Gorman54a6eb52008-04-28 02:12:16 -07001637 int classzone_idx;
Mel Gorman5117f452009-06-16 15:31:59 -07001638 struct zone *zone;
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001639 nodemask_t *allowednodes = NULL;/* zonelist_cache approximation */
1640 int zlc_active = 0; /* set if using zonelist_cache */
1641 int did_zlc_setup = 0; /* just call zlc_setup() one time */
Mel Gorman54a6eb52008-04-28 02:12:16 -07001642
Mel Gorman19770b32008-04-28 02:12:18 -07001643 classzone_idx = zone_idx(preferred_zone);
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001644zonelist_scan:
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001645 /*
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001646 * Scan zonelist, looking for a zone with enough free.
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001647 * See also cpuset_zone_allowed() comment in kernel/cpuset.c.
1648 */
Mel Gorman19770b32008-04-28 02:12:18 -07001649 for_each_zone_zonelist_nodemask(zone, z, zonelist,
1650 high_zoneidx, nodemask) {
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001651 if (NUMA_BUILD && zlc_active &&
1652 !zlc_zone_worth_trying(zonelist, z, allowednodes))
1653 continue;
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001654 if ((alloc_flags & ALLOC_CPUSET) &&
Paul Jackson02a0e532006-12-13 00:34:25 -08001655 !cpuset_zone_allowed_softwall(zone, gfp_mask))
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001656 goto try_next_zone;
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001657
Mel Gorman41858962009-06-16 15:32:12 -07001658 BUILD_BUG_ON(ALLOC_NO_WATERMARKS < NR_WMARK);
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001659 if (!(alloc_flags & ALLOC_NO_WATERMARKS)) {
Nick Piggin31488902005-11-28 13:44:03 -08001660 unsigned long mark;
Mel Gormanfa5e0842009-06-16 15:33:22 -07001661 int ret;
1662
Mel Gorman41858962009-06-16 15:32:12 -07001663 mark = zone->watermark[alloc_flags & ALLOC_WMARK_MASK];
Mel Gormanfa5e0842009-06-16 15:33:22 -07001664 if (zone_watermark_ok(zone, order, mark,
1665 classzone_idx, alloc_flags))
1666 goto try_this_zone;
1667
1668 if (zone_reclaim_mode == 0)
1669 goto this_zone_full;
1670
1671 ret = zone_reclaim(zone, gfp_mask, order);
1672 switch (ret) {
1673 case ZONE_RECLAIM_NOSCAN:
1674 /* did not scan */
1675 goto try_next_zone;
1676 case ZONE_RECLAIM_FULL:
1677 /* scanned but unreclaimable */
1678 goto this_zone_full;
1679 default:
1680 /* did we reclaim enough */
1681 if (!zone_watermark_ok(zone, order, mark,
1682 classzone_idx, alloc_flags))
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001683 goto this_zone_full;
Paul Jackson0798e512006-12-06 20:31:38 -08001684 }
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001685 }
1686
Mel Gormanfa5e0842009-06-16 15:33:22 -07001687try_this_zone:
Mel Gorman3dd28262009-06-16 15:32:00 -07001688 page = buffered_rmqueue(preferred_zone, zone, order,
1689 gfp_mask, migratetype);
Paul Jackson0798e512006-12-06 20:31:38 -08001690 if (page)
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001691 break;
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001692this_zone_full:
1693 if (NUMA_BUILD)
1694 zlc_mark_zone_full(zonelist, z);
1695try_next_zone:
Christoph Lameter62bc62a2009-06-16 15:32:15 -07001696 if (NUMA_BUILD && !did_zlc_setup && nr_online_nodes > 1) {
Mel Gormand395b732009-06-16 15:32:09 -07001697 /*
1698 * we do zlc_setup after the first zone is tried but only
1699 * if there are multiple nodes make it worthwhile
1700 */
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001701 allowednodes = zlc_setup(zonelist, alloc_flags);
1702 zlc_active = 1;
1703 did_zlc_setup = 1;
1704 }
Mel Gorman54a6eb52008-04-28 02:12:16 -07001705 }
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001706
1707 if (unlikely(NUMA_BUILD && page == NULL && zlc_active)) {
1708 /* Disable zlc cache for second zonelist scan */
1709 zlc_active = 0;
1710 goto zonelist_scan;
1711 }
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001712 return page;
Martin Hicks753ee722005-06-21 17:14:41 -07001713}
1714
Mel Gorman11e33f62009-06-16 15:31:57 -07001715static inline int
1716should_alloc_retry(gfp_t gfp_mask, unsigned int order,
1717 unsigned long pages_reclaimed)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001718{
Mel Gorman11e33f62009-06-16 15:31:57 -07001719 /* Do not loop if specifically requested */
1720 if (gfp_mask & __GFP_NORETRY)
1721 return 0;
1722
1723 /*
1724 * In this implementation, order <= PAGE_ALLOC_COSTLY_ORDER
1725 * means __GFP_NOFAIL, but that may not be true in other
1726 * implementations.
1727 */
1728 if (order <= PAGE_ALLOC_COSTLY_ORDER)
1729 return 1;
1730
1731 /*
1732 * For order > PAGE_ALLOC_COSTLY_ORDER, if __GFP_REPEAT is
1733 * specified, then we retry until we no longer reclaim any pages
1734 * (above), or we've reclaimed an order of pages at least as
1735 * large as the allocation's order. In both cases, if the
1736 * allocation still fails, we stop retrying.
1737 */
1738 if (gfp_mask & __GFP_REPEAT && pages_reclaimed < (1 << order))
1739 return 1;
1740
1741 /*
1742 * Don't let big-order allocations loop unless the caller
1743 * explicitly requests that.
1744 */
1745 if (gfp_mask & __GFP_NOFAIL)
1746 return 1;
1747
1748 return 0;
1749}
1750
1751static inline struct page *
1752__alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order,
1753 struct zonelist *zonelist, enum zone_type high_zoneidx,
Mel Gorman3dd28262009-06-16 15:32:00 -07001754 nodemask_t *nodemask, struct zone *preferred_zone,
1755 int migratetype)
Mel Gorman11e33f62009-06-16 15:31:57 -07001756{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001757 struct page *page;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001758
Mel Gorman11e33f62009-06-16 15:31:57 -07001759 /* Acquire the OOM killer lock for the zones in zonelist */
Minchan Kimff321fe2010-08-09 17:18:57 -07001760 if (!try_set_zonelist_oom(zonelist, gfp_mask)) {
Mel Gorman11e33f62009-06-16 15:31:57 -07001761 schedule_timeout_uninterruptible(1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001762 return NULL;
1763 }
Jens Axboe6b1de912005-11-17 21:35:02 +01001764
Mel Gorman11e33f62009-06-16 15:31:57 -07001765 /*
1766 * Go through the zonelist yet one more time, keep very high watermark
1767 * here, this is only to catch a parallel oom killing, we must fail if
1768 * we're still under heavy pressure.
1769 */
1770 page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask,
1771 order, zonelist, high_zoneidx,
Mel Gorman5117f452009-06-16 15:31:59 -07001772 ALLOC_WMARK_HIGH|ALLOC_CPUSET,
Mel Gorman3dd28262009-06-16 15:32:00 -07001773 preferred_zone, migratetype);
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001774 if (page)
Mel Gorman11e33f62009-06-16 15:31:57 -07001775 goto out;
1776
KAMEZAWA Hiroyuki4365a562009-12-15 16:45:33 -08001777 if (!(gfp_mask & __GFP_NOFAIL)) {
1778 /* The OOM killer will not help higher order allocs */
1779 if (order > PAGE_ALLOC_COSTLY_ORDER)
1780 goto out;
David Rientjes03668b32010-08-09 17:18:54 -07001781 /* The OOM killer does not needlessly kill tasks for lowmem */
1782 if (high_zoneidx < ZONE_NORMAL)
1783 goto out;
KAMEZAWA Hiroyuki4365a562009-12-15 16:45:33 -08001784 /*
1785 * GFP_THISNODE contains __GFP_NORETRY and we never hit this.
1786 * Sanity check for bare calls of __GFP_THISNODE, not real OOM.
1787 * The caller should handle page allocation failure by itself if
1788 * it specifies __GFP_THISNODE.
1789 * Note: Hugepage uses it but will hit PAGE_ALLOC_COSTLY_ORDER.
1790 */
1791 if (gfp_mask & __GFP_THISNODE)
1792 goto out;
1793 }
Mel Gorman11e33f62009-06-16 15:31:57 -07001794 /* Exhausted what can be done so it's blamo time */
KAMEZAWA Hiroyuki4365a562009-12-15 16:45:33 -08001795 out_of_memory(zonelist, gfp_mask, order, nodemask);
Mel Gorman11e33f62009-06-16 15:31:57 -07001796
1797out:
1798 clear_zonelist_oom(zonelist, gfp_mask);
1799 return page;
1800}
1801
Mel Gorman56de7262010-05-24 14:32:30 -07001802#ifdef CONFIG_COMPACTION
1803/* Try memory compaction for high-order allocations before reclaim */
1804static struct page *
1805__alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order,
1806 struct zonelist *zonelist, enum zone_type high_zoneidx,
1807 nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone,
Mel Gorman77f1fe62011-01-13 15:45:57 -08001808 int migratetype, unsigned long *did_some_progress,
1809 bool sync_migration)
Mel Gorman56de7262010-05-24 14:32:30 -07001810{
1811 struct page *page;
1812
Mel Gorman4f92e252010-05-24 14:32:32 -07001813 if (!order || compaction_deferred(preferred_zone))
Mel Gorman56de7262010-05-24 14:32:30 -07001814 return NULL;
1815
Andrew Mortonc06b1fc2011-01-13 15:47:32 -08001816 current->flags |= PF_MEMALLOC;
Mel Gorman56de7262010-05-24 14:32:30 -07001817 *did_some_progress = try_to_compact_pages(zonelist, order, gfp_mask,
Mel Gorman77f1fe62011-01-13 15:45:57 -08001818 nodemask, sync_migration);
Andrew Mortonc06b1fc2011-01-13 15:47:32 -08001819 current->flags &= ~PF_MEMALLOC;
Mel Gorman56de7262010-05-24 14:32:30 -07001820 if (*did_some_progress != COMPACT_SKIPPED) {
1821
1822 /* Page migration frees to the PCP lists but we want merging */
1823 drain_pages(get_cpu());
1824 put_cpu();
1825
1826 page = get_page_from_freelist(gfp_mask, nodemask,
1827 order, zonelist, high_zoneidx,
1828 alloc_flags, preferred_zone,
1829 migratetype);
1830 if (page) {
Mel Gorman4f92e252010-05-24 14:32:32 -07001831 preferred_zone->compact_considered = 0;
1832 preferred_zone->compact_defer_shift = 0;
Mel Gorman56de7262010-05-24 14:32:30 -07001833 count_vm_event(COMPACTSUCCESS);
1834 return page;
1835 }
1836
1837 /*
1838 * It's bad if compaction run occurs and fails.
1839 * The most likely reason is that pages exist,
1840 * but not enough to satisfy watermarks.
1841 */
1842 count_vm_event(COMPACTFAIL);
Mel Gorman4f92e252010-05-24 14:32:32 -07001843 defer_compaction(preferred_zone);
Mel Gorman56de7262010-05-24 14:32:30 -07001844
1845 cond_resched();
1846 }
1847
1848 return NULL;
1849}
1850#else
1851static inline struct page *
1852__alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order,
1853 struct zonelist *zonelist, enum zone_type high_zoneidx,
1854 nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone,
Mel Gorman77f1fe62011-01-13 15:45:57 -08001855 int migratetype, unsigned long *did_some_progress,
1856 bool sync_migration)
Mel Gorman56de7262010-05-24 14:32:30 -07001857{
1858 return NULL;
1859}
1860#endif /* CONFIG_COMPACTION */
1861
Mel Gorman11e33f62009-06-16 15:31:57 -07001862/* The really slow allocator path where we enter direct reclaim */
1863static inline struct page *
1864__alloc_pages_direct_reclaim(gfp_t gfp_mask, unsigned int order,
1865 struct zonelist *zonelist, enum zone_type high_zoneidx,
Mel Gorman5117f452009-06-16 15:31:59 -07001866 nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone,
Mel Gorman3dd28262009-06-16 15:32:00 -07001867 int migratetype, unsigned long *did_some_progress)
Mel Gorman11e33f62009-06-16 15:31:57 -07001868{
1869 struct page *page = NULL;
1870 struct reclaim_state reclaim_state;
Mel Gorman9ee493c2010-09-09 16:38:18 -07001871 bool drained = false;
Mel Gorman11e33f62009-06-16 15:31:57 -07001872
1873 cond_resched();
1874
1875 /* We now go into synchronous reclaim */
1876 cpuset_memory_pressure_bump();
Andrew Mortonc06b1fc2011-01-13 15:47:32 -08001877 current->flags |= PF_MEMALLOC;
Mel Gorman11e33f62009-06-16 15:31:57 -07001878 lockdep_set_current_reclaim_state(gfp_mask);
1879 reclaim_state.reclaimed_slab = 0;
Andrew Mortonc06b1fc2011-01-13 15:47:32 -08001880 current->reclaim_state = &reclaim_state;
Mel Gorman11e33f62009-06-16 15:31:57 -07001881
1882 *did_some_progress = try_to_free_pages(zonelist, order, gfp_mask, nodemask);
1883
Andrew Mortonc06b1fc2011-01-13 15:47:32 -08001884 current->reclaim_state = NULL;
Mel Gorman11e33f62009-06-16 15:31:57 -07001885 lockdep_clear_current_reclaim_state();
Andrew Mortonc06b1fc2011-01-13 15:47:32 -08001886 current->flags &= ~PF_MEMALLOC;
Mel Gorman11e33f62009-06-16 15:31:57 -07001887
1888 cond_resched();
1889
Mel Gorman9ee493c2010-09-09 16:38:18 -07001890 if (unlikely(!(*did_some_progress)))
1891 return NULL;
Mel Gorman11e33f62009-06-16 15:31:57 -07001892
Mel Gorman9ee493c2010-09-09 16:38:18 -07001893retry:
1894 page = get_page_from_freelist(gfp_mask, nodemask, order,
Mel Gorman5117f452009-06-16 15:31:59 -07001895 zonelist, high_zoneidx,
Mel Gorman3dd28262009-06-16 15:32:00 -07001896 alloc_flags, preferred_zone,
1897 migratetype);
Mel Gorman9ee493c2010-09-09 16:38:18 -07001898
1899 /*
1900 * If an allocation failed after direct reclaim, it could be because
1901 * pages are pinned on the per-cpu lists. Drain them and try again
1902 */
1903 if (!page && !drained) {
1904 drain_all_pages();
1905 drained = true;
1906 goto retry;
1907 }
1908
Mel Gorman11e33f62009-06-16 15:31:57 -07001909 return page;
1910}
1911
Mel Gorman11e33f62009-06-16 15:31:57 -07001912/*
1913 * This is called in the allocator slow-path if the allocation request is of
1914 * sufficient urgency to ignore watermarks and take other desperate measures
1915 */
1916static inline struct page *
1917__alloc_pages_high_priority(gfp_t gfp_mask, unsigned int order,
1918 struct zonelist *zonelist, enum zone_type high_zoneidx,
Mel Gorman3dd28262009-06-16 15:32:00 -07001919 nodemask_t *nodemask, struct zone *preferred_zone,
1920 int migratetype)
Mel Gorman11e33f62009-06-16 15:31:57 -07001921{
1922 struct page *page;
1923
1924 do {
1925 page = get_page_from_freelist(gfp_mask, nodemask, order,
Mel Gorman5117f452009-06-16 15:31:59 -07001926 zonelist, high_zoneidx, ALLOC_NO_WATERMARKS,
Mel Gorman3dd28262009-06-16 15:32:00 -07001927 preferred_zone, migratetype);
Mel Gorman11e33f62009-06-16 15:31:57 -07001928
1929 if (!page && gfp_mask & __GFP_NOFAIL)
Mel Gorman0e093d992010-10-26 14:21:45 -07001930 wait_iff_congested(preferred_zone, BLK_RW_ASYNC, HZ/50);
Mel Gorman11e33f62009-06-16 15:31:57 -07001931 } while (!page && (gfp_mask & __GFP_NOFAIL));
1932
1933 return page;
1934}
1935
1936static inline
1937void wake_all_kswapd(unsigned int order, struct zonelist *zonelist,
Mel Gorman99504742011-01-13 15:46:20 -08001938 enum zone_type high_zoneidx,
1939 enum zone_type classzone_idx)
Mel Gorman11e33f62009-06-16 15:31:57 -07001940{
1941 struct zoneref *z;
1942 struct zone *zone;
1943
1944 for_each_zone_zonelist(zone, z, zonelist, high_zoneidx)
Mel Gorman99504742011-01-13 15:46:20 -08001945 wakeup_kswapd(zone, order, classzone_idx);
Mel Gorman11e33f62009-06-16 15:31:57 -07001946}
1947
Peter Zijlstra341ce062009-06-16 15:32:02 -07001948static inline int
1949gfp_to_alloc_flags(gfp_t gfp_mask)
1950{
Peter Zijlstra341ce062009-06-16 15:32:02 -07001951 int alloc_flags = ALLOC_WMARK_MIN | ALLOC_CPUSET;
1952 const gfp_t wait = gfp_mask & __GFP_WAIT;
1953
Mel Gormana56f57f2009-06-16 15:32:02 -07001954 /* __GFP_HIGH is assumed to be the same as ALLOC_HIGH to save a branch. */
Namhyung Kime6223a32010-10-26 14:21:59 -07001955 BUILD_BUG_ON(__GFP_HIGH != (__force gfp_t) ALLOC_HIGH);
Mel Gormana56f57f2009-06-16 15:32:02 -07001956
Peter Zijlstra341ce062009-06-16 15:32:02 -07001957 /*
1958 * The caller may dip into page reserves a bit more if the caller
1959 * cannot run direct reclaim, or if the caller has realtime scheduling
1960 * policy or is asking for __GFP_HIGH memory. GFP_ATOMIC requests will
1961 * set both ALLOC_HARDER (!wait) and ALLOC_HIGH (__GFP_HIGH).
1962 */
Namhyung Kime6223a32010-10-26 14:21:59 -07001963 alloc_flags |= (__force int) (gfp_mask & __GFP_HIGH);
Peter Zijlstra341ce062009-06-16 15:32:02 -07001964
1965 if (!wait) {
Andrea Arcangeli5c3240d2011-01-13 15:46:49 -08001966 /*
1967 * Not worth trying to allocate harder for
1968 * __GFP_NOMEMALLOC even if it can't schedule.
1969 */
1970 if (!(gfp_mask & __GFP_NOMEMALLOC))
1971 alloc_flags |= ALLOC_HARDER;
Peter Zijlstra341ce062009-06-16 15:32:02 -07001972 /*
1973 * Ignore cpuset if GFP_ATOMIC (!wait) rather than fail alloc.
1974 * See also cpuset_zone_allowed() comment in kernel/cpuset.c.
1975 */
1976 alloc_flags &= ~ALLOC_CPUSET;
Andrew Mortonc06b1fc2011-01-13 15:47:32 -08001977 } else if (unlikely(rt_task(current)) && !in_interrupt())
Peter Zijlstra341ce062009-06-16 15:32:02 -07001978 alloc_flags |= ALLOC_HARDER;
1979
1980 if (likely(!(gfp_mask & __GFP_NOMEMALLOC))) {
1981 if (!in_interrupt() &&
Andrew Mortonc06b1fc2011-01-13 15:47:32 -08001982 ((current->flags & PF_MEMALLOC) ||
Peter Zijlstra341ce062009-06-16 15:32:02 -07001983 unlikely(test_thread_flag(TIF_MEMDIE))))
1984 alloc_flags |= ALLOC_NO_WATERMARKS;
1985 }
1986
1987 return alloc_flags;
1988}
1989
Mel Gorman11e33f62009-06-16 15:31:57 -07001990static inline struct page *
1991__alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order,
1992 struct zonelist *zonelist, enum zone_type high_zoneidx,
Mel Gorman3dd28262009-06-16 15:32:00 -07001993 nodemask_t *nodemask, struct zone *preferred_zone,
1994 int migratetype)
Mel Gorman11e33f62009-06-16 15:31:57 -07001995{
1996 const gfp_t wait = gfp_mask & __GFP_WAIT;
1997 struct page *page = NULL;
1998 int alloc_flags;
1999 unsigned long pages_reclaimed = 0;
2000 unsigned long did_some_progress;
Mel Gorman77f1fe62011-01-13 15:45:57 -08002001 bool sync_migration = false;
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08002002
Christoph Lameter952f3b52006-12-06 20:33:26 -08002003 /*
Mel Gorman72807a72009-06-16 15:32:18 -07002004 * In the slowpath, we sanity check order to avoid ever trying to
2005 * reclaim >= MAX_ORDER areas which will never succeed. Callers may
2006 * be using allocators in order of preference for an area that is
2007 * too large.
2008 */
Mel Gorman1fc28b72009-07-29 15:04:08 -07002009 if (order >= MAX_ORDER) {
2010 WARN_ON_ONCE(!(gfp_mask & __GFP_NOWARN));
Mel Gorman72807a72009-06-16 15:32:18 -07002011 return NULL;
Mel Gorman1fc28b72009-07-29 15:04:08 -07002012 }
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08002013
Christoph Lameter952f3b52006-12-06 20:33:26 -08002014 /*
2015 * GFP_THISNODE (meaning __GFP_THISNODE, __GFP_NORETRY and
2016 * __GFP_NOWARN set) should not cause reclaim since the subsystem
2017 * (f.e. slab) using GFP_THISNODE may choose to trigger reclaim
2018 * using a larger set of nodes after it has established that the
2019 * allowed per node queues are empty and that nodes are
2020 * over allocated.
2021 */
2022 if (NUMA_BUILD && (gfp_mask & GFP_THISNODE) == GFP_THISNODE)
2023 goto nopage;
2024
Mel Gormancc4a6852009-11-11 14:26:14 -08002025restart:
Andrea Arcangeli32dba982011-01-13 15:46:49 -08002026 if (!(gfp_mask & __GFP_NO_KSWAPD))
2027 wake_all_kswapd(order, zonelist, high_zoneidx,
Mel Gorman99504742011-01-13 15:46:20 -08002028 zone_idx(preferred_zone));
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08002029
Paul Jackson9bf22292005-09-06 15:18:12 -07002030 /*
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08002031 * OK, we're below the kswapd watermark and have kicked background
2032 * reclaim. Now things get more complex, so set up alloc_flags according
2033 * to how we want to proceed.
Paul Jackson9bf22292005-09-06 15:18:12 -07002034 */
Peter Zijlstra341ce062009-06-16 15:32:02 -07002035 alloc_flags = gfp_to_alloc_flags(gfp_mask);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002036
Peter Zijlstra341ce062009-06-16 15:32:02 -07002037 /* This is the last chance, in general, before the goto nopage. */
Mel Gorman19770b32008-04-28 02:12:18 -07002038 page = get_page_from_freelist(gfp_mask, nodemask, order, zonelist,
Peter Zijlstra341ce062009-06-16 15:32:02 -07002039 high_zoneidx, alloc_flags & ~ALLOC_NO_WATERMARKS,
2040 preferred_zone, migratetype);
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08002041 if (page)
2042 goto got_pg;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002043
Kirill Korotaevb43a57b2006-12-06 20:32:27 -08002044rebalance:
Mel Gorman11e33f62009-06-16 15:31:57 -07002045 /* Allocate without watermarks if the context allows */
Peter Zijlstra341ce062009-06-16 15:32:02 -07002046 if (alloc_flags & ALLOC_NO_WATERMARKS) {
2047 page = __alloc_pages_high_priority(gfp_mask, order,
2048 zonelist, high_zoneidx, nodemask,
2049 preferred_zone, migratetype);
2050 if (page)
2051 goto got_pg;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002052 }
2053
2054 /* Atomic allocations - we can't balance anything */
2055 if (!wait)
2056 goto nopage;
2057
Peter Zijlstra341ce062009-06-16 15:32:02 -07002058 /* Avoid recursion of direct reclaim */
Andrew Mortonc06b1fc2011-01-13 15:47:32 -08002059 if (current->flags & PF_MEMALLOC)
Peter Zijlstra341ce062009-06-16 15:32:02 -07002060 goto nopage;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002061
David Rientjes6583bb62009-07-29 15:02:06 -07002062 /* Avoid allocations with no watermarks from looping endlessly */
2063 if (test_thread_flag(TIF_MEMDIE) && !(gfp_mask & __GFP_NOFAIL))
2064 goto nopage;
2065
Mel Gorman77f1fe62011-01-13 15:45:57 -08002066 /*
2067 * Try direct compaction. The first pass is asynchronous. Subsequent
2068 * attempts after direct reclaim are synchronous
2069 */
Mel Gorman56de7262010-05-24 14:32:30 -07002070 page = __alloc_pages_direct_compact(gfp_mask, order,
2071 zonelist, high_zoneidx,
2072 nodemask,
2073 alloc_flags, preferred_zone,
Mel Gorman77f1fe62011-01-13 15:45:57 -08002074 migratetype, &did_some_progress,
2075 sync_migration);
Mel Gorman56de7262010-05-24 14:32:30 -07002076 if (page)
2077 goto got_pg;
Mel Gorman77f1fe62011-01-13 15:45:57 -08002078 sync_migration = true;
Mel Gorman56de7262010-05-24 14:32:30 -07002079
Mel Gorman11e33f62009-06-16 15:31:57 -07002080 /* Try direct reclaim and then allocating */
2081 page = __alloc_pages_direct_reclaim(gfp_mask, order,
2082 zonelist, high_zoneidx,
2083 nodemask,
Mel Gorman5117f452009-06-16 15:31:59 -07002084 alloc_flags, preferred_zone,
Mel Gorman3dd28262009-06-16 15:32:00 -07002085 migratetype, &did_some_progress);
Mel Gorman11e33f62009-06-16 15:31:57 -07002086 if (page)
2087 goto got_pg;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002088
Linus Torvalds1da177e2005-04-16 15:20:36 -07002089 /*
Mel Gorman11e33f62009-06-16 15:31:57 -07002090 * If we failed to make any progress reclaiming, then we are
2091 * running out of options and have to consider going OOM
Linus Torvalds1da177e2005-04-16 15:20:36 -07002092 */
Mel Gorman11e33f62009-06-16 15:31:57 -07002093 if (!did_some_progress) {
2094 if ((gfp_mask & __GFP_FS) && !(gfp_mask & __GFP_NORETRY)) {
Rafael J. Wysocki7f33d492009-06-16 15:32:41 -07002095 if (oom_killer_disabled)
2096 goto nopage;
Mel Gorman11e33f62009-06-16 15:31:57 -07002097 page = __alloc_pages_may_oom(gfp_mask, order,
2098 zonelist, high_zoneidx,
Mel Gorman3dd28262009-06-16 15:32:00 -07002099 nodemask, preferred_zone,
2100 migratetype);
Mel Gorman11e33f62009-06-16 15:31:57 -07002101 if (page)
2102 goto got_pg;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002103
David Rientjes03668b32010-08-09 17:18:54 -07002104 if (!(gfp_mask & __GFP_NOFAIL)) {
2105 /*
2106 * The oom killer is not called for high-order
2107 * allocations that may fail, so if no progress
2108 * is being made, there are no other options and
2109 * retrying is unlikely to help.
2110 */
2111 if (order > PAGE_ALLOC_COSTLY_ORDER)
2112 goto nopage;
2113 /*
2114 * The oom killer is not called for lowmem
2115 * allocations to prevent needlessly killing
2116 * innocent tasks.
2117 */
2118 if (high_zoneidx < ZONE_NORMAL)
2119 goto nopage;
2120 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002121
Linus Torvalds1da177e2005-04-16 15:20:36 -07002122 goto restart;
2123 }
2124 }
2125
Mel Gorman11e33f62009-06-16 15:31:57 -07002126 /* Check if we should retry the allocation */
Nishanth Aravamudana41f24e2008-04-29 00:58:25 -07002127 pages_reclaimed += did_some_progress;
Mel Gorman11e33f62009-06-16 15:31:57 -07002128 if (should_alloc_retry(gfp_mask, order, pages_reclaimed)) {
2129 /* Wait for some write requests to complete then retry */
Mel Gorman0e093d992010-10-26 14:21:45 -07002130 wait_iff_congested(preferred_zone, BLK_RW_ASYNC, HZ/50);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002131 goto rebalance;
Mel Gorman3e7d3442011-01-13 15:45:56 -08002132 } else {
2133 /*
2134 * High-order allocations do not necessarily loop after
2135 * direct reclaim and reclaim/compaction depends on compaction
2136 * being called after reclaim so call directly if necessary
2137 */
2138 page = __alloc_pages_direct_compact(gfp_mask, order,
2139 zonelist, high_zoneidx,
2140 nodemask,
2141 alloc_flags, preferred_zone,
Mel Gorman77f1fe62011-01-13 15:45:57 -08002142 migratetype, &did_some_progress,
2143 sync_migration);
Mel Gorman3e7d3442011-01-13 15:45:56 -08002144 if (page)
2145 goto got_pg;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002146 }
2147
2148nopage:
2149 if (!(gfp_mask & __GFP_NOWARN) && printk_ratelimit()) {
2150 printk(KERN_WARNING "%s: page allocation failure."
2151 " order:%d, mode:0x%x\n",
Andrew Mortonc06b1fc2011-01-13 15:47:32 -08002152 current->comm, order, gfp_mask);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002153 dump_stack();
Janet Morgan578c2fd2005-06-21 17:14:56 -07002154 show_mem();
Linus Torvalds1da177e2005-04-16 15:20:36 -07002155 }
Vegard Nossumb1eeab62008-11-25 16:55:53 +01002156 return page;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002157got_pg:
Vegard Nossumb1eeab62008-11-25 16:55:53 +01002158 if (kmemcheck_enabled)
2159 kmemcheck_pagealloc_alloc(page, order, gfp_mask);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002160 return page;
Mel Gorman11e33f62009-06-16 15:31:57 -07002161
Linus Torvalds1da177e2005-04-16 15:20:36 -07002162}
Mel Gorman11e33f62009-06-16 15:31:57 -07002163
2164/*
2165 * This is the 'heart' of the zoned buddy allocator.
2166 */
2167struct page *
2168__alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
2169 struct zonelist *zonelist, nodemask_t *nodemask)
2170{
2171 enum zone_type high_zoneidx = gfp_zone(gfp_mask);
Mel Gorman5117f452009-06-16 15:31:59 -07002172 struct zone *preferred_zone;
Mel Gorman11e33f62009-06-16 15:31:57 -07002173 struct page *page;
Mel Gorman3dd28262009-06-16 15:32:00 -07002174 int migratetype = allocflags_to_migratetype(gfp_mask);
Mel Gorman11e33f62009-06-16 15:31:57 -07002175
Benjamin Herrenschmidtdcce2842009-06-18 13:24:12 +10002176 gfp_mask &= gfp_allowed_mask;
2177
Mel Gorman11e33f62009-06-16 15:31:57 -07002178 lockdep_trace_alloc(gfp_mask);
2179
2180 might_sleep_if(gfp_mask & __GFP_WAIT);
2181
2182 if (should_fail_alloc_page(gfp_mask, order))
2183 return NULL;
2184
2185 /*
2186 * Check the zones suitable for the gfp_mask contain at least one
2187 * valid zone. It's possible to have an empty zonelist as a result
2188 * of GFP_THISNODE and a memoryless node
2189 */
2190 if (unlikely(!zonelist->_zonerefs->zone))
2191 return NULL;
2192
Miao Xiec0ff7452010-05-24 14:32:08 -07002193 get_mems_allowed();
Mel Gorman5117f452009-06-16 15:31:59 -07002194 /* The preferred zone is used for statistics later */
2195 first_zones_zonelist(zonelist, high_zoneidx, nodemask, &preferred_zone);
Miao Xiec0ff7452010-05-24 14:32:08 -07002196 if (!preferred_zone) {
2197 put_mems_allowed();
Mel Gorman5117f452009-06-16 15:31:59 -07002198 return NULL;
Miao Xiec0ff7452010-05-24 14:32:08 -07002199 }
Mel Gorman5117f452009-06-16 15:31:59 -07002200
2201 /* First allocation attempt */
Mel Gorman11e33f62009-06-16 15:31:57 -07002202 page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask, order,
Mel Gorman5117f452009-06-16 15:31:59 -07002203 zonelist, high_zoneidx, ALLOC_WMARK_LOW|ALLOC_CPUSET,
Mel Gorman3dd28262009-06-16 15:32:00 -07002204 preferred_zone, migratetype);
Mel Gorman11e33f62009-06-16 15:31:57 -07002205 if (unlikely(!page))
2206 page = __alloc_pages_slowpath(gfp_mask, order,
Mel Gorman5117f452009-06-16 15:31:59 -07002207 zonelist, high_zoneidx, nodemask,
Mel Gorman3dd28262009-06-16 15:32:00 -07002208 preferred_zone, migratetype);
Miao Xiec0ff7452010-05-24 14:32:08 -07002209 put_mems_allowed();
Mel Gorman11e33f62009-06-16 15:31:57 -07002210
Mel Gorman4b4f2782009-09-21 17:02:41 -07002211 trace_mm_page_alloc(page, order, gfp_mask, migratetype);
Mel Gorman11e33f62009-06-16 15:31:57 -07002212 return page;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002213}
Mel Gormand2391712009-06-16 15:31:52 -07002214EXPORT_SYMBOL(__alloc_pages_nodemask);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002215
2216/*
2217 * Common helper functions.
2218 */
Harvey Harrison920c7a52008-02-04 22:29:26 -08002219unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002220{
Akinobu Mita945a1112009-09-21 17:01:47 -07002221 struct page *page;
2222
2223 /*
2224 * __get_free_pages() returns a 32-bit address, which cannot represent
2225 * a highmem page
2226 */
2227 VM_BUG_ON((gfp_mask & __GFP_HIGHMEM) != 0);
2228
Linus Torvalds1da177e2005-04-16 15:20:36 -07002229 page = alloc_pages(gfp_mask, order);
2230 if (!page)
2231 return 0;
2232 return (unsigned long) page_address(page);
2233}
Linus Torvalds1da177e2005-04-16 15:20:36 -07002234EXPORT_SYMBOL(__get_free_pages);
2235
Harvey Harrison920c7a52008-02-04 22:29:26 -08002236unsigned long get_zeroed_page(gfp_t gfp_mask)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002237{
Akinobu Mita945a1112009-09-21 17:01:47 -07002238 return __get_free_pages(gfp_mask | __GFP_ZERO, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002239}
Linus Torvalds1da177e2005-04-16 15:20:36 -07002240EXPORT_SYMBOL(get_zeroed_page);
2241
2242void __pagevec_free(struct pagevec *pvec)
2243{
2244 int i = pagevec_count(pvec);
2245
Mel Gorman4b4f2782009-09-21 17:02:41 -07002246 while (--i >= 0) {
2247 trace_mm_pagevec_free(pvec->pages[i], pvec->cold);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002248 free_hot_cold_page(pvec->pages[i], pvec->cold);
Mel Gorman4b4f2782009-09-21 17:02:41 -07002249 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002250}
2251
Harvey Harrison920c7a52008-02-04 22:29:26 -08002252void __free_pages(struct page *page, unsigned int order)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002253{
Nick Pigginb5810032005-10-29 18:16:12 -07002254 if (put_page_testzero(page)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002255 if (order == 0)
Li Hongfc916682010-03-05 13:41:54 -08002256 free_hot_cold_page(page, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002257 else
2258 __free_pages_ok(page, order);
2259 }
2260}
2261
2262EXPORT_SYMBOL(__free_pages);
2263
Harvey Harrison920c7a52008-02-04 22:29:26 -08002264void free_pages(unsigned long addr, unsigned int order)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002265{
2266 if (addr != 0) {
Nick Piggin725d7042006-09-25 23:30:55 -07002267 VM_BUG_ON(!virt_addr_valid((void *)addr));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002268 __free_pages(virt_to_page((void *)addr), order);
2269 }
2270}
2271
2272EXPORT_SYMBOL(free_pages);
2273
Timur Tabi2be0ffe2008-07-23 21:28:11 -07002274/**
2275 * alloc_pages_exact - allocate an exact number physically-contiguous pages.
2276 * @size: the number of bytes to allocate
2277 * @gfp_mask: GFP flags for the allocation
2278 *
2279 * This function is similar to alloc_pages(), except that it allocates the
2280 * minimum number of pages to satisfy the request. alloc_pages() can only
2281 * allocate memory in power-of-two pages.
2282 *
2283 * This function is also limited by MAX_ORDER.
2284 *
2285 * Memory allocated by this function must be released by free_pages_exact().
2286 */
2287void *alloc_pages_exact(size_t size, gfp_t gfp_mask)
2288{
2289 unsigned int order = get_order(size);
2290 unsigned long addr;
2291
2292 addr = __get_free_pages(gfp_mask, order);
2293 if (addr) {
2294 unsigned long alloc_end = addr + (PAGE_SIZE << order);
2295 unsigned long used = addr + PAGE_ALIGN(size);
2296
Kevin Cernekee5bfd7562009-07-05 12:08:19 -07002297 split_page(virt_to_page((void *)addr), order);
Timur Tabi2be0ffe2008-07-23 21:28:11 -07002298 while (used < alloc_end) {
2299 free_page(used);
2300 used += PAGE_SIZE;
2301 }
2302 }
2303
2304 return (void *)addr;
2305}
2306EXPORT_SYMBOL(alloc_pages_exact);
2307
2308/**
2309 * free_pages_exact - release memory allocated via alloc_pages_exact()
2310 * @virt: the value returned by alloc_pages_exact.
2311 * @size: size of allocation, same value as passed to alloc_pages_exact().
2312 *
2313 * Release the memory allocated by a previous call to alloc_pages_exact.
2314 */
2315void free_pages_exact(void *virt, size_t size)
2316{
2317 unsigned long addr = (unsigned long)virt;
2318 unsigned long end = addr + PAGE_ALIGN(size);
2319
2320 while (addr < end) {
2321 free_page(addr);
2322 addr += PAGE_SIZE;
2323 }
2324}
2325EXPORT_SYMBOL(free_pages_exact);
2326
Linus Torvalds1da177e2005-04-16 15:20:36 -07002327static unsigned int nr_free_zone_pages(int offset)
2328{
Mel Gormandd1a2392008-04-28 02:12:17 -07002329 struct zoneref *z;
Mel Gorman54a6eb52008-04-28 02:12:16 -07002330 struct zone *zone;
2331
Martin J. Blighe310fd42005-07-29 22:59:18 -07002332 /* Just pick one node, since fallback list is circular */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002333 unsigned int sum = 0;
2334
Mel Gorman0e884602008-04-28 02:12:14 -07002335 struct zonelist *zonelist = node_zonelist(numa_node_id(), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002336
Mel Gorman54a6eb52008-04-28 02:12:16 -07002337 for_each_zone_zonelist(zone, z, zonelist, offset) {
Martin J. Blighe310fd42005-07-29 22:59:18 -07002338 unsigned long size = zone->present_pages;
Mel Gorman41858962009-06-16 15:32:12 -07002339 unsigned long high = high_wmark_pages(zone);
Martin J. Blighe310fd42005-07-29 22:59:18 -07002340 if (size > high)
2341 sum += size - high;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002342 }
2343
2344 return sum;
2345}
2346
2347/*
2348 * Amount of free RAM allocatable within ZONE_DMA and ZONE_NORMAL
2349 */
2350unsigned int nr_free_buffer_pages(void)
2351{
Al Viroaf4ca452005-10-21 02:55:38 -04002352 return nr_free_zone_pages(gfp_zone(GFP_USER));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002353}
Meelap Shahc2f1a552007-07-17 04:04:39 -07002354EXPORT_SYMBOL_GPL(nr_free_buffer_pages);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002355
2356/*
2357 * Amount of free RAM allocatable within all zones
2358 */
2359unsigned int nr_free_pagecache_pages(void)
2360{
Mel Gorman2a1e2742007-07-17 04:03:12 -07002361 return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002362}
Christoph Lameter08e0f6a2006-09-27 01:50:06 -07002363
2364static inline void show_node(struct zone *zone)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002365{
Christoph Lameter08e0f6a2006-09-27 01:50:06 -07002366 if (NUMA_BUILD)
Andy Whitcroft25ba77c2006-12-06 20:33:03 -08002367 printk("Node %d ", zone_to_nid(zone));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002368}
Linus Torvalds1da177e2005-04-16 15:20:36 -07002369
Linus Torvalds1da177e2005-04-16 15:20:36 -07002370void si_meminfo(struct sysinfo *val)
2371{
2372 val->totalram = totalram_pages;
2373 val->sharedram = 0;
Christoph Lameterd23ad422007-02-10 01:43:02 -08002374 val->freeram = global_page_state(NR_FREE_PAGES);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002375 val->bufferram = nr_blockdev_pages();
Linus Torvalds1da177e2005-04-16 15:20:36 -07002376 val->totalhigh = totalhigh_pages;
2377 val->freehigh = nr_free_highpages();
Linus Torvalds1da177e2005-04-16 15:20:36 -07002378 val->mem_unit = PAGE_SIZE;
2379}
2380
2381EXPORT_SYMBOL(si_meminfo);
2382
2383#ifdef CONFIG_NUMA
2384void si_meminfo_node(struct sysinfo *val, int nid)
2385{
2386 pg_data_t *pgdat = NODE_DATA(nid);
2387
2388 val->totalram = pgdat->node_present_pages;
Christoph Lameterd23ad422007-02-10 01:43:02 -08002389 val->freeram = node_page_state(nid, NR_FREE_PAGES);
Christoph Lameter98d2b0e2006-09-25 23:31:12 -07002390#ifdef CONFIG_HIGHMEM
Linus Torvalds1da177e2005-04-16 15:20:36 -07002391 val->totalhigh = pgdat->node_zones[ZONE_HIGHMEM].present_pages;
Christoph Lameterd23ad422007-02-10 01:43:02 -08002392 val->freehigh = zone_page_state(&pgdat->node_zones[ZONE_HIGHMEM],
2393 NR_FREE_PAGES);
Christoph Lameter98d2b0e2006-09-25 23:31:12 -07002394#else
2395 val->totalhigh = 0;
2396 val->freehigh = 0;
2397#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07002398 val->mem_unit = PAGE_SIZE;
2399}
2400#endif
2401
2402#define K(x) ((x) << (PAGE_SHIFT-10))
2403
2404/*
2405 * Show free area list (used inside shift_scroll-lock stuff)
2406 * We also calculate the percentage fragmentation. We do this by counting the
2407 * memory on each free list with the exception of the first item on the list.
2408 */
2409void show_free_areas(void)
2410{
Jes Sorensenc7241912006-09-27 01:50:05 -07002411 int cpu;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002412 struct zone *zone;
2413
KOSAKI Motohiroee99c712009-03-31 15:19:31 -07002414 for_each_populated_zone(zone) {
Jes Sorensenc7241912006-09-27 01:50:05 -07002415 show_node(zone);
2416 printk("%s per-cpu:\n", zone->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002417
Dave Jones6b482c62005-11-10 15:45:56 -05002418 for_each_online_cpu(cpu) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002419 struct per_cpu_pageset *pageset;
2420
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09002421 pageset = per_cpu_ptr(zone->pageset, cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002422
Christoph Lameter3dfa5722008-02-04 22:29:19 -08002423 printk("CPU %4d: hi:%5d, btch:%4d usd:%4d\n",
2424 cpu, pageset->pcp.high,
2425 pageset->pcp.batch, pageset->pcp.count);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002426 }
2427 }
2428
KOSAKI Motohiroa7312862009-09-21 17:01:37 -07002429 printk("active_anon:%lu inactive_anon:%lu isolated_anon:%lu\n"
2430 " active_file:%lu inactive_file:%lu isolated_file:%lu\n"
Lee Schermerhorn7b854122008-10-18 20:26:40 -07002431 " unevictable:%lu"
Andrew Mortonb76146e2009-10-26 16:49:52 -07002432 " dirty:%lu writeback:%lu unstable:%lu\n"
KOSAKI Motohiro3701b032009-09-21 17:01:29 -07002433 " free:%lu slab_reclaimable:%lu slab_unreclaimable:%lu\n"
KOSAKI Motohiro4b021082009-09-21 17:01:33 -07002434 " mapped:%lu shmem:%lu pagetables:%lu bounce:%lu\n",
Rik van Riel4f98a2f2008-10-18 20:26:32 -07002435 global_page_state(NR_ACTIVE_ANON),
Rik van Riel4f98a2f2008-10-18 20:26:32 -07002436 global_page_state(NR_INACTIVE_ANON),
KOSAKI Motohiroa7312862009-09-21 17:01:37 -07002437 global_page_state(NR_ISOLATED_ANON),
2438 global_page_state(NR_ACTIVE_FILE),
Rik van Riel4f98a2f2008-10-18 20:26:32 -07002439 global_page_state(NR_INACTIVE_FILE),
KOSAKI Motohiroa7312862009-09-21 17:01:37 -07002440 global_page_state(NR_ISOLATED_FILE),
Lee Schermerhorn7b854122008-10-18 20:26:40 -07002441 global_page_state(NR_UNEVICTABLE),
Christoph Lameterb1e7a8f2006-06-30 01:55:39 -07002442 global_page_state(NR_FILE_DIRTY),
Christoph Lameterce866b32006-06-30 01:55:40 -07002443 global_page_state(NR_WRITEBACK),
Christoph Lameterfd39fc82006-06-30 01:55:40 -07002444 global_page_state(NR_UNSTABLE_NFS),
Christoph Lameterd23ad422007-02-10 01:43:02 -08002445 global_page_state(NR_FREE_PAGES),
KOSAKI Motohiro3701b032009-09-21 17:01:29 -07002446 global_page_state(NR_SLAB_RECLAIMABLE),
2447 global_page_state(NR_SLAB_UNRECLAIMABLE),
Christoph Lameter65ba55f2006-06-30 01:55:34 -07002448 global_page_state(NR_FILE_MAPPED),
KOSAKI Motohiro4b021082009-09-21 17:01:33 -07002449 global_page_state(NR_SHMEM),
Andrew Mortona25700a2007-02-08 14:20:40 -08002450 global_page_state(NR_PAGETABLE),
2451 global_page_state(NR_BOUNCE));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002452
KOSAKI Motohiroee99c712009-03-31 15:19:31 -07002453 for_each_populated_zone(zone) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002454 int i;
2455
2456 show_node(zone);
2457 printk("%s"
2458 " free:%lukB"
2459 " min:%lukB"
2460 " low:%lukB"
2461 " high:%lukB"
Rik van Riel4f98a2f2008-10-18 20:26:32 -07002462 " active_anon:%lukB"
2463 " inactive_anon:%lukB"
2464 " active_file:%lukB"
2465 " inactive_file:%lukB"
Lee Schermerhorn7b854122008-10-18 20:26:40 -07002466 " unevictable:%lukB"
KOSAKI Motohiroa7312862009-09-21 17:01:37 -07002467 " isolated(anon):%lukB"
2468 " isolated(file):%lukB"
Linus Torvalds1da177e2005-04-16 15:20:36 -07002469 " present:%lukB"
KOSAKI Motohiro4a0aa732009-09-21 17:01:30 -07002470 " mlocked:%lukB"
2471 " dirty:%lukB"
2472 " writeback:%lukB"
2473 " mapped:%lukB"
KOSAKI Motohiro4b021082009-09-21 17:01:33 -07002474 " shmem:%lukB"
KOSAKI Motohiro4a0aa732009-09-21 17:01:30 -07002475 " slab_reclaimable:%lukB"
2476 " slab_unreclaimable:%lukB"
KOSAKI Motohiroc6a7f572009-09-21 17:01:32 -07002477 " kernel_stack:%lukB"
KOSAKI Motohiro4a0aa732009-09-21 17:01:30 -07002478 " pagetables:%lukB"
2479 " unstable:%lukB"
2480 " bounce:%lukB"
2481 " writeback_tmp:%lukB"
Linus Torvalds1da177e2005-04-16 15:20:36 -07002482 " pages_scanned:%lu"
2483 " all_unreclaimable? %s"
2484 "\n",
2485 zone->name,
Mel Gorman88f5acf2011-01-13 15:45:41 -08002486 K(zone_page_state(zone, NR_FREE_PAGES)),
Mel Gorman41858962009-06-16 15:32:12 -07002487 K(min_wmark_pages(zone)),
2488 K(low_wmark_pages(zone)),
2489 K(high_wmark_pages(zone)),
Rik van Riel4f98a2f2008-10-18 20:26:32 -07002490 K(zone_page_state(zone, NR_ACTIVE_ANON)),
2491 K(zone_page_state(zone, NR_INACTIVE_ANON)),
2492 K(zone_page_state(zone, NR_ACTIVE_FILE)),
2493 K(zone_page_state(zone, NR_INACTIVE_FILE)),
Lee Schermerhorn7b854122008-10-18 20:26:40 -07002494 K(zone_page_state(zone, NR_UNEVICTABLE)),
KOSAKI Motohiroa7312862009-09-21 17:01:37 -07002495 K(zone_page_state(zone, NR_ISOLATED_ANON)),
2496 K(zone_page_state(zone, NR_ISOLATED_FILE)),
Linus Torvalds1da177e2005-04-16 15:20:36 -07002497 K(zone->present_pages),
KOSAKI Motohiro4a0aa732009-09-21 17:01:30 -07002498 K(zone_page_state(zone, NR_MLOCK)),
2499 K(zone_page_state(zone, NR_FILE_DIRTY)),
2500 K(zone_page_state(zone, NR_WRITEBACK)),
2501 K(zone_page_state(zone, NR_FILE_MAPPED)),
KOSAKI Motohiro4b021082009-09-21 17:01:33 -07002502 K(zone_page_state(zone, NR_SHMEM)),
KOSAKI Motohiro4a0aa732009-09-21 17:01:30 -07002503 K(zone_page_state(zone, NR_SLAB_RECLAIMABLE)),
2504 K(zone_page_state(zone, NR_SLAB_UNRECLAIMABLE)),
KOSAKI Motohiroc6a7f572009-09-21 17:01:32 -07002505 zone_page_state(zone, NR_KERNEL_STACK) *
2506 THREAD_SIZE / 1024,
KOSAKI Motohiro4a0aa732009-09-21 17:01:30 -07002507 K(zone_page_state(zone, NR_PAGETABLE)),
2508 K(zone_page_state(zone, NR_UNSTABLE_NFS)),
2509 K(zone_page_state(zone, NR_BOUNCE)),
2510 K(zone_page_state(zone, NR_WRITEBACK_TEMP)),
Linus Torvalds1da177e2005-04-16 15:20:36 -07002511 zone->pages_scanned,
KOSAKI Motohiro93e4a892010-03-05 13:41:55 -08002512 (zone->all_unreclaimable ? "yes" : "no")
Linus Torvalds1da177e2005-04-16 15:20:36 -07002513 );
2514 printk("lowmem_reserve[]:");
2515 for (i = 0; i < MAX_NR_ZONES; i++)
2516 printk(" %lu", zone->lowmem_reserve[i]);
2517 printk("\n");
2518 }
2519
KOSAKI Motohiroee99c712009-03-31 15:19:31 -07002520 for_each_populated_zone(zone) {
Kirill Korotaev8f9de512006-06-23 02:03:50 -07002521 unsigned long nr[MAX_ORDER], flags, order, total = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002522
2523 show_node(zone);
2524 printk("%s: ", zone->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002525
2526 spin_lock_irqsave(&zone->lock, flags);
2527 for (order = 0; order < MAX_ORDER; order++) {
Kirill Korotaev8f9de512006-06-23 02:03:50 -07002528 nr[order] = zone->free_area[order].nr_free;
2529 total += nr[order] << order;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002530 }
2531 spin_unlock_irqrestore(&zone->lock, flags);
Kirill Korotaev8f9de512006-06-23 02:03:50 -07002532 for (order = 0; order < MAX_ORDER; order++)
2533 printk("%lu*%lukB ", nr[order], K(1UL) << order);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002534 printk("= %lukB\n", K(total));
2535 }
2536
Larry Woodmane6f36022008-02-04 22:29:30 -08002537 printk("%ld total pagecache pages\n", global_page_state(NR_FILE_PAGES));
2538
Linus Torvalds1da177e2005-04-16 15:20:36 -07002539 show_swap_cache_info();
2540}
2541
Mel Gorman19770b32008-04-28 02:12:18 -07002542static void zoneref_set_zone(struct zone *zone, struct zoneref *zoneref)
2543{
2544 zoneref->zone = zone;
2545 zoneref->zone_idx = zone_idx(zone);
2546}
2547
Linus Torvalds1da177e2005-04-16 15:20:36 -07002548/*
2549 * Builds allocation fallback zone lists.
Christoph Lameter1a932052006-01-06 00:11:16 -08002550 *
2551 * Add all populated zones of a node to the zonelist.
Linus Torvalds1da177e2005-04-16 15:20:36 -07002552 */
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002553static int build_zonelists_node(pg_data_t *pgdat, struct zonelist *zonelist,
2554 int nr_zones, enum zone_type zone_type)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002555{
Christoph Lameter1a932052006-01-06 00:11:16 -08002556 struct zone *zone;
2557
Christoph Lameter98d2b0e2006-09-25 23:31:12 -07002558 BUG_ON(zone_type >= MAX_NR_ZONES);
Christoph Lameter2f6726e2006-09-25 23:31:18 -07002559 zone_type++;
Christoph Lameter02a68a52006-01-06 00:11:18 -08002560
2561 do {
Christoph Lameter2f6726e2006-09-25 23:31:18 -07002562 zone_type--;
Christoph Lameter070f8032006-01-06 00:11:19 -08002563 zone = pgdat->node_zones + zone_type;
Christoph Lameter1a932052006-01-06 00:11:16 -08002564 if (populated_zone(zone)) {
Mel Gormandd1a2392008-04-28 02:12:17 -07002565 zoneref_set_zone(zone,
2566 &zonelist->_zonerefs[nr_zones++]);
Christoph Lameter070f8032006-01-06 00:11:19 -08002567 check_highest_zone(zone_type);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002568 }
Christoph Lameter02a68a52006-01-06 00:11:18 -08002569
Christoph Lameter2f6726e2006-09-25 23:31:18 -07002570 } while (zone_type);
Christoph Lameter070f8032006-01-06 00:11:19 -08002571 return nr_zones;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002572}
2573
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002574
2575/*
2576 * zonelist_order:
2577 * 0 = automatic detection of better ordering.
2578 * 1 = order by ([node] distance, -zonetype)
2579 * 2 = order by (-zonetype, [node] distance)
2580 *
2581 * If not NUMA, ZONELIST_ORDER_ZONE and ZONELIST_ORDER_NODE will create
2582 * the same zonelist. So only NUMA can configure this param.
2583 */
2584#define ZONELIST_ORDER_DEFAULT 0
2585#define ZONELIST_ORDER_NODE 1
2586#define ZONELIST_ORDER_ZONE 2
2587
2588/* zonelist order in the kernel.
2589 * set_zonelist_order() will set this to NODE or ZONE.
2590 */
2591static int current_zonelist_order = ZONELIST_ORDER_DEFAULT;
2592static char zonelist_order_name[3][8] = {"Default", "Node", "Zone"};
2593
2594
Linus Torvalds1da177e2005-04-16 15:20:36 -07002595#ifdef CONFIG_NUMA
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002596/* The value user specified ....changed by config */
2597static int user_zonelist_order = ZONELIST_ORDER_DEFAULT;
2598/* string for sysctl */
2599#define NUMA_ZONELIST_ORDER_LEN 16
2600char numa_zonelist_order[16] = "default";
2601
2602/*
2603 * interface for configure zonelist ordering.
2604 * command line option "numa_zonelist_order"
2605 * = "[dD]efault - default, automatic configuration.
2606 * = "[nN]ode - order by node locality, then by zone within node
2607 * = "[zZ]one - order by zone, then by locality within zone
2608 */
2609
2610static int __parse_numa_zonelist_order(char *s)
2611{
2612 if (*s == 'd' || *s == 'D') {
2613 user_zonelist_order = ZONELIST_ORDER_DEFAULT;
2614 } else if (*s == 'n' || *s == 'N') {
2615 user_zonelist_order = ZONELIST_ORDER_NODE;
2616 } else if (*s == 'z' || *s == 'Z') {
2617 user_zonelist_order = ZONELIST_ORDER_ZONE;
2618 } else {
2619 printk(KERN_WARNING
2620 "Ignoring invalid numa_zonelist_order value: "
2621 "%s\n", s);
2622 return -EINVAL;
2623 }
2624 return 0;
2625}
2626
2627static __init int setup_numa_zonelist_order(char *s)
2628{
Volodymyr G. Lukiianykecb256f2011-01-13 15:46:26 -08002629 int ret;
2630
2631 if (!s)
2632 return 0;
2633
2634 ret = __parse_numa_zonelist_order(s);
2635 if (ret == 0)
2636 strlcpy(numa_zonelist_order, s, NUMA_ZONELIST_ORDER_LEN);
2637
2638 return ret;
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002639}
2640early_param("numa_zonelist_order", setup_numa_zonelist_order);
2641
2642/*
2643 * sysctl handler for numa_zonelist_order
2644 */
2645int numa_zonelist_order_handler(ctl_table *table, int write,
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07002646 void __user *buffer, size_t *length,
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002647 loff_t *ppos)
2648{
2649 char saved_string[NUMA_ZONELIST_ORDER_LEN];
2650 int ret;
Andi Kleen443c6f12009-12-23 21:00:47 +01002651 static DEFINE_MUTEX(zl_order_mutex);
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002652
Andi Kleen443c6f12009-12-23 21:00:47 +01002653 mutex_lock(&zl_order_mutex);
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002654 if (write)
Andi Kleen443c6f12009-12-23 21:00:47 +01002655 strcpy(saved_string, (char*)table->data);
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07002656 ret = proc_dostring(table, write, buffer, length, ppos);
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002657 if (ret)
Andi Kleen443c6f12009-12-23 21:00:47 +01002658 goto out;
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002659 if (write) {
2660 int oldval = user_zonelist_order;
2661 if (__parse_numa_zonelist_order((char*)table->data)) {
2662 /*
2663 * bogus value. restore saved string
2664 */
2665 strncpy((char*)table->data, saved_string,
2666 NUMA_ZONELIST_ORDER_LEN);
2667 user_zonelist_order = oldval;
Haicheng Li4eaf3f62010-05-24 14:32:52 -07002668 } else if (oldval != user_zonelist_order) {
2669 mutex_lock(&zonelists_mutex);
Haicheng Li1f522502010-05-24 14:32:51 -07002670 build_all_zonelists(NULL);
Haicheng Li4eaf3f62010-05-24 14:32:52 -07002671 mutex_unlock(&zonelists_mutex);
2672 }
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002673 }
Andi Kleen443c6f12009-12-23 21:00:47 +01002674out:
2675 mutex_unlock(&zl_order_mutex);
2676 return ret;
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002677}
2678
2679
Christoph Lameter62bc62a2009-06-16 15:32:15 -07002680#define MAX_NODE_LOAD (nr_online_nodes)
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002681static int node_load[MAX_NUMNODES];
2682
Linus Torvalds1da177e2005-04-16 15:20:36 -07002683/**
Pavel Pisa4dc3b162005-05-01 08:59:25 -07002684 * find_next_best_node - find the next node that should appear in a given node's fallback list
Linus Torvalds1da177e2005-04-16 15:20:36 -07002685 * @node: node whose fallback list we're appending
2686 * @used_node_mask: nodemask_t of already used nodes
2687 *
2688 * We use a number of factors to determine which is the next node that should
2689 * appear on a given node's fallback list. The node should not have appeared
2690 * already in @node's fallback list, and it should be the next closest node
2691 * according to the distance array (which contains arbitrary distance values
2692 * from each node to each node in the system), and should also prefer nodes
2693 * with no CPUs, since presumably they'll have very little allocation pressure
2694 * on them otherwise.
2695 * It returns -1 if no node is found.
2696 */
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002697static int find_next_best_node(int node, nodemask_t *used_node_mask)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002698{
Linus Torvalds4cf808e2006-02-17 20:38:21 +01002699 int n, val;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002700 int min_val = INT_MAX;
2701 int best_node = -1;
Rusty Russella70f7302009-03-13 14:49:46 +10302702 const struct cpumask *tmp = cpumask_of_node(0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002703
Linus Torvalds4cf808e2006-02-17 20:38:21 +01002704 /* Use the local node if we haven't already */
2705 if (!node_isset(node, *used_node_mask)) {
2706 node_set(node, *used_node_mask);
2707 return node;
2708 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002709
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07002710 for_each_node_state(n, N_HIGH_MEMORY) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002711
2712 /* Don't want a node to appear more than once */
2713 if (node_isset(n, *used_node_mask))
2714 continue;
2715
Linus Torvalds1da177e2005-04-16 15:20:36 -07002716 /* Use the distance array to find the distance */
2717 val = node_distance(node, n);
2718
Linus Torvalds4cf808e2006-02-17 20:38:21 +01002719 /* Penalize nodes under us ("prefer the next node") */
2720 val += (n < node);
2721
Linus Torvalds1da177e2005-04-16 15:20:36 -07002722 /* Give preference to headless and unused nodes */
Rusty Russella70f7302009-03-13 14:49:46 +10302723 tmp = cpumask_of_node(n);
2724 if (!cpumask_empty(tmp))
Linus Torvalds1da177e2005-04-16 15:20:36 -07002725 val += PENALTY_FOR_NODE_WITH_CPUS;
2726
2727 /* Slight preference for less loaded node */
2728 val *= (MAX_NODE_LOAD*MAX_NUMNODES);
2729 val += node_load[n];
2730
2731 if (val < min_val) {
2732 min_val = val;
2733 best_node = n;
2734 }
2735 }
2736
2737 if (best_node >= 0)
2738 node_set(best_node, *used_node_mask);
2739
2740 return best_node;
2741}
2742
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002743
2744/*
2745 * Build zonelists ordered by node and zones within node.
2746 * This results in maximum locality--normal zone overflows into local
2747 * DMA zone, if any--but risks exhausting DMA zone.
2748 */
2749static void build_zonelists_in_node_order(pg_data_t *pgdat, int node)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002750{
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002751 int j;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002752 struct zonelist *zonelist;
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002753
Mel Gorman54a6eb52008-04-28 02:12:16 -07002754 zonelist = &pgdat->node_zonelists[0];
Mel Gormandd1a2392008-04-28 02:12:17 -07002755 for (j = 0; zonelist->_zonerefs[j].zone != NULL; j++)
Mel Gorman54a6eb52008-04-28 02:12:16 -07002756 ;
2757 j = build_zonelists_node(NODE_DATA(node), zonelist, j,
2758 MAX_NR_ZONES - 1);
Mel Gormandd1a2392008-04-28 02:12:17 -07002759 zonelist->_zonerefs[j].zone = NULL;
2760 zonelist->_zonerefs[j].zone_idx = 0;
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002761}
2762
2763/*
Christoph Lameter523b9452007-10-16 01:25:37 -07002764 * Build gfp_thisnode zonelists
2765 */
2766static void build_thisnode_zonelists(pg_data_t *pgdat)
2767{
Christoph Lameter523b9452007-10-16 01:25:37 -07002768 int j;
2769 struct zonelist *zonelist;
2770
Mel Gorman54a6eb52008-04-28 02:12:16 -07002771 zonelist = &pgdat->node_zonelists[1];
2772 j = build_zonelists_node(pgdat, zonelist, 0, MAX_NR_ZONES - 1);
Mel Gormandd1a2392008-04-28 02:12:17 -07002773 zonelist->_zonerefs[j].zone = NULL;
2774 zonelist->_zonerefs[j].zone_idx = 0;
Christoph Lameter523b9452007-10-16 01:25:37 -07002775}
2776
2777/*
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002778 * Build zonelists ordered by zone and nodes within zones.
2779 * This results in conserving DMA zone[s] until all Normal memory is
2780 * exhausted, but results in overflowing to remote node while memory
2781 * may still exist in local DMA zone.
2782 */
2783static int node_order[MAX_NUMNODES];
2784
2785static void build_zonelists_in_zone_order(pg_data_t *pgdat, int nr_nodes)
2786{
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002787 int pos, j, node;
2788 int zone_type; /* needs to be signed */
2789 struct zone *z;
2790 struct zonelist *zonelist;
2791
Mel Gorman54a6eb52008-04-28 02:12:16 -07002792 zonelist = &pgdat->node_zonelists[0];
2793 pos = 0;
2794 for (zone_type = MAX_NR_ZONES - 1; zone_type >= 0; zone_type--) {
2795 for (j = 0; j < nr_nodes; j++) {
2796 node = node_order[j];
2797 z = &NODE_DATA(node)->node_zones[zone_type];
2798 if (populated_zone(z)) {
Mel Gormandd1a2392008-04-28 02:12:17 -07002799 zoneref_set_zone(z,
2800 &zonelist->_zonerefs[pos++]);
Mel Gorman54a6eb52008-04-28 02:12:16 -07002801 check_highest_zone(zone_type);
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002802 }
2803 }
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002804 }
Mel Gormandd1a2392008-04-28 02:12:17 -07002805 zonelist->_zonerefs[pos].zone = NULL;
2806 zonelist->_zonerefs[pos].zone_idx = 0;
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002807}
2808
2809static int default_zonelist_order(void)
2810{
2811 int nid, zone_type;
2812 unsigned long low_kmem_size,total_size;
2813 struct zone *z;
2814 int average_size;
2815 /*
Thomas Weber88393162010-03-16 11:47:56 +01002816 * ZONE_DMA and ZONE_DMA32 can be very small area in the system.
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002817 * If they are really small and used heavily, the system can fall
2818 * into OOM very easily.
David Rientjese325c902010-05-24 14:32:13 -07002819 * This function detect ZONE_DMA/DMA32 size and configures zone order.
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002820 */
2821 /* Is there ZONE_NORMAL ? (ex. ppc has only DMA zone..) */
2822 low_kmem_size = 0;
2823 total_size = 0;
2824 for_each_online_node(nid) {
2825 for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++) {
2826 z = &NODE_DATA(nid)->node_zones[zone_type];
2827 if (populated_zone(z)) {
2828 if (zone_type < ZONE_NORMAL)
2829 low_kmem_size += z->present_pages;
2830 total_size += z->present_pages;
David Rientjese325c902010-05-24 14:32:13 -07002831 } else if (zone_type == ZONE_NORMAL) {
2832 /*
2833 * If any node has only lowmem, then node order
2834 * is preferred to allow kernel allocations
2835 * locally; otherwise, they can easily infringe
2836 * on other nodes when there is an abundance of
2837 * lowmem available to allocate from.
2838 */
2839 return ZONELIST_ORDER_NODE;
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002840 }
2841 }
2842 }
2843 if (!low_kmem_size || /* there are no DMA area. */
2844 low_kmem_size > total_size/2) /* DMA/DMA32 is big. */
2845 return ZONELIST_ORDER_NODE;
2846 /*
2847 * look into each node's config.
2848 * If there is a node whose DMA/DMA32 memory is very big area on
2849 * local memory, NODE_ORDER may be suitable.
2850 */
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07002851 average_size = total_size /
2852 (nodes_weight(node_states[N_HIGH_MEMORY]) + 1);
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002853 for_each_online_node(nid) {
2854 low_kmem_size = 0;
2855 total_size = 0;
2856 for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++) {
2857 z = &NODE_DATA(nid)->node_zones[zone_type];
2858 if (populated_zone(z)) {
2859 if (zone_type < ZONE_NORMAL)
2860 low_kmem_size += z->present_pages;
2861 total_size += z->present_pages;
2862 }
2863 }
2864 if (low_kmem_size &&
2865 total_size > average_size && /* ignore small node */
2866 low_kmem_size > total_size * 70/100)
2867 return ZONELIST_ORDER_NODE;
2868 }
2869 return ZONELIST_ORDER_ZONE;
2870}
2871
2872static void set_zonelist_order(void)
2873{
2874 if (user_zonelist_order == ZONELIST_ORDER_DEFAULT)
2875 current_zonelist_order = default_zonelist_order();
2876 else
2877 current_zonelist_order = user_zonelist_order;
2878}
2879
2880static void build_zonelists(pg_data_t *pgdat)
2881{
2882 int j, node, load;
2883 enum zone_type i;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002884 nodemask_t used_mask;
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002885 int local_node, prev_node;
2886 struct zonelist *zonelist;
2887 int order = current_zonelist_order;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002888
2889 /* initialize zonelists */
Christoph Lameter523b9452007-10-16 01:25:37 -07002890 for (i = 0; i < MAX_ZONELISTS; i++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002891 zonelist = pgdat->node_zonelists + i;
Mel Gormandd1a2392008-04-28 02:12:17 -07002892 zonelist->_zonerefs[0].zone = NULL;
2893 zonelist->_zonerefs[0].zone_idx = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002894 }
2895
2896 /* NUMA-aware ordering of nodes */
2897 local_node = pgdat->node_id;
Christoph Lameter62bc62a2009-06-16 15:32:15 -07002898 load = nr_online_nodes;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002899 prev_node = local_node;
2900 nodes_clear(used_mask);
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002901
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002902 memset(node_order, 0, sizeof(node_order));
2903 j = 0;
2904
Linus Torvalds1da177e2005-04-16 15:20:36 -07002905 while ((node = find_next_best_node(local_node, &used_mask)) >= 0) {
Christoph Lameter9eeff232006-01-18 17:42:31 -08002906 int distance = node_distance(local_node, node);
2907
2908 /*
2909 * If another node is sufficiently far away then it is better
2910 * to reclaim pages in a zone before going off node.
2911 */
2912 if (distance > RECLAIM_DISTANCE)
2913 zone_reclaim_mode = 1;
2914
Linus Torvalds1da177e2005-04-16 15:20:36 -07002915 /*
2916 * We don't want to pressure a particular node.
2917 * So adding penalty to the first node in same
2918 * distance group to make it round-robin.
2919 */
Christoph Lameter9eeff232006-01-18 17:42:31 -08002920 if (distance != node_distance(local_node, prev_node))
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002921 node_load[node] = load;
2922
Linus Torvalds1da177e2005-04-16 15:20:36 -07002923 prev_node = node;
2924 load--;
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002925 if (order == ZONELIST_ORDER_NODE)
2926 build_zonelists_in_node_order(pgdat, node);
2927 else
2928 node_order[j++] = node; /* remember order */
2929 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002930
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002931 if (order == ZONELIST_ORDER_ZONE) {
2932 /* calculate node order -- i.e., DMA last! */
2933 build_zonelists_in_zone_order(pgdat, j);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002934 }
Christoph Lameter523b9452007-10-16 01:25:37 -07002935
2936 build_thisnode_zonelists(pgdat);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002937}
2938
Paul Jackson9276b1bc2006-12-06 20:31:48 -08002939/* Construct the zonelist performance cache - see further mmzone.h */
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002940static void build_zonelist_cache(pg_data_t *pgdat)
Paul Jackson9276b1bc2006-12-06 20:31:48 -08002941{
Mel Gorman54a6eb52008-04-28 02:12:16 -07002942 struct zonelist *zonelist;
2943 struct zonelist_cache *zlc;
Mel Gormandd1a2392008-04-28 02:12:17 -07002944 struct zoneref *z;
Paul Jackson9276b1bc2006-12-06 20:31:48 -08002945
Mel Gorman54a6eb52008-04-28 02:12:16 -07002946 zonelist = &pgdat->node_zonelists[0];
2947 zonelist->zlcache_ptr = zlc = &zonelist->zlcache;
2948 bitmap_zero(zlc->fullzones, MAX_ZONES_PER_ZONELIST);
Mel Gormandd1a2392008-04-28 02:12:17 -07002949 for (z = zonelist->_zonerefs; z->zone; z++)
2950 zlc->z_to_n[z - zonelist->_zonerefs] = zonelist_node_idx(z);
Paul Jackson9276b1bc2006-12-06 20:31:48 -08002951}
2952
Lee Schermerhorn7aac7892010-05-26 14:45:00 -07002953#ifdef CONFIG_HAVE_MEMORYLESS_NODES
2954/*
2955 * Return node id of node used for "local" allocations.
2956 * I.e., first node id of first zone in arg node's generic zonelist.
2957 * Used for initializing percpu 'numa_mem', which is used primarily
2958 * for kernel allocations, so use GFP_KERNEL flags to locate zonelist.
2959 */
2960int local_memory_node(int node)
2961{
2962 struct zone *zone;
2963
2964 (void)first_zones_zonelist(node_zonelist(node, GFP_KERNEL),
2965 gfp_zone(GFP_KERNEL),
2966 NULL,
2967 &zone);
2968 return zone->node;
2969}
2970#endif
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002971
Linus Torvalds1da177e2005-04-16 15:20:36 -07002972#else /* CONFIG_NUMA */
2973
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002974static void set_zonelist_order(void)
2975{
2976 current_zonelist_order = ZONELIST_ORDER_ZONE;
2977}
2978
2979static void build_zonelists(pg_data_t *pgdat)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002980{
Christoph Lameter19655d32006-09-25 23:31:19 -07002981 int node, local_node;
Mel Gorman54a6eb52008-04-28 02:12:16 -07002982 enum zone_type j;
2983 struct zonelist *zonelist;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002984
2985 local_node = pgdat->node_id;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002986
Mel Gorman54a6eb52008-04-28 02:12:16 -07002987 zonelist = &pgdat->node_zonelists[0];
2988 j = build_zonelists_node(pgdat, zonelist, 0, MAX_NR_ZONES - 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002989
Mel Gorman54a6eb52008-04-28 02:12:16 -07002990 /*
2991 * Now we build the zonelist so that it contains the zones
2992 * of all the other nodes.
2993 * We don't want to pressure a particular node, so when
2994 * building the zones for node N, we make sure that the
2995 * zones coming right after the local ones are those from
2996 * node N+1 (modulo N)
2997 */
2998 for (node = local_node + 1; node < MAX_NUMNODES; node++) {
2999 if (!node_online(node))
3000 continue;
3001 j = build_zonelists_node(NODE_DATA(node), zonelist, j,
3002 MAX_NR_ZONES - 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003003 }
Mel Gorman54a6eb52008-04-28 02:12:16 -07003004 for (node = 0; node < local_node; node++) {
3005 if (!node_online(node))
3006 continue;
3007 j = build_zonelists_node(NODE_DATA(node), zonelist, j,
3008 MAX_NR_ZONES - 1);
3009 }
3010
Mel Gormandd1a2392008-04-28 02:12:17 -07003011 zonelist->_zonerefs[j].zone = NULL;
3012 zonelist->_zonerefs[j].zone_idx = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003013}
3014
Paul Jackson9276b1bc2006-12-06 20:31:48 -08003015/* non-NUMA variant of zonelist performance cache - just NULL zlcache_ptr */
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07003016static void build_zonelist_cache(pg_data_t *pgdat)
Paul Jackson9276b1bc2006-12-06 20:31:48 -08003017{
Mel Gorman54a6eb52008-04-28 02:12:16 -07003018 pgdat->node_zonelists[0].zlcache_ptr = NULL;
Paul Jackson9276b1bc2006-12-06 20:31:48 -08003019}
3020
Linus Torvalds1da177e2005-04-16 15:20:36 -07003021#endif /* CONFIG_NUMA */
3022
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09003023/*
3024 * Boot pageset table. One per cpu which is going to be used for all
3025 * zones and all nodes. The parameters will be set in such a way
3026 * that an item put on a list will immediately be handed over to
3027 * the buddy list. This is safe since pageset manipulation is done
3028 * with interrupts disabled.
3029 *
3030 * The boot_pagesets must be kept even after bootup is complete for
3031 * unused processors and/or zones. They do play a role for bootstrapping
3032 * hotplugged processors.
3033 *
3034 * zoneinfo_show() and maybe other functions do
3035 * not check if the processor is online before following the pageset pointer.
3036 * Other parts of the kernel may not check if the zone is available.
3037 */
3038static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch);
3039static DEFINE_PER_CPU(struct per_cpu_pageset, boot_pageset);
Haicheng Li1f522502010-05-24 14:32:51 -07003040static void setup_zone_pageset(struct zone *zone);
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09003041
Haicheng Li4eaf3f62010-05-24 14:32:52 -07003042/*
3043 * Global mutex to protect against size modification of zonelists
3044 * as well as to serialize pageset setup for the new populated zone.
3045 */
3046DEFINE_MUTEX(zonelists_mutex);
3047
Rusty Russell9b1a4d32008-07-28 12:16:30 -05003048/* return values int ....just for stop_machine() */
Haicheng Li1f522502010-05-24 14:32:51 -07003049static __init_refok int __build_all_zonelists(void *data)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003050{
Yasunori Goto68113782006-06-23 02:03:11 -07003051 int nid;
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09003052 int cpu;
Paul Jackson9276b1bc2006-12-06 20:31:48 -08003053
Bo Liu7f9cfb32009-08-18 14:11:19 -07003054#ifdef CONFIG_NUMA
3055 memset(node_load, 0, sizeof(node_load));
3056#endif
Paul Jackson9276b1bc2006-12-06 20:31:48 -08003057 for_each_online_node(nid) {
Christoph Lameter7ea15302007-10-16 01:25:29 -07003058 pg_data_t *pgdat = NODE_DATA(nid);
3059
3060 build_zonelists(pgdat);
3061 build_zonelist_cache(pgdat);
Paul Jackson9276b1bc2006-12-06 20:31:48 -08003062 }
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09003063
3064 /*
3065 * Initialize the boot_pagesets that are going to be used
3066 * for bootstrapping processors. The real pagesets for
3067 * each zone will be allocated later when the per cpu
3068 * allocator is available.
3069 *
3070 * boot_pagesets are used also for bootstrapping offline
3071 * cpus if the system is already booted because the pagesets
3072 * are needed to initialize allocators on a specific cpu too.
3073 * F.e. the percpu allocator needs the page allocator which
3074 * needs the percpu allocator in order to allocate its pagesets
3075 * (a chicken-egg dilemma).
3076 */
Lee Schermerhorn7aac7892010-05-26 14:45:00 -07003077 for_each_possible_cpu(cpu) {
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09003078 setup_pageset(&per_cpu(boot_pageset, cpu), 0);
3079
Lee Schermerhorn7aac7892010-05-26 14:45:00 -07003080#ifdef CONFIG_HAVE_MEMORYLESS_NODES
3081 /*
3082 * We now know the "local memory node" for each node--
3083 * i.e., the node of the first zone in the generic zonelist.
3084 * Set up numa_mem percpu variable for on-line cpus. During
3085 * boot, only the boot cpu should be on-line; we'll init the
3086 * secondary cpus' numa_mem as they come on-line. During
3087 * node/memory hotplug, we'll fixup all on-line cpus.
3088 */
3089 if (cpu_online(cpu))
3090 set_cpu_numa_mem(cpu, local_memory_node(cpu_to_node(cpu)));
3091#endif
3092 }
3093
Yasunori Goto68113782006-06-23 02:03:11 -07003094 return 0;
3095}
Linus Torvalds1da177e2005-04-16 15:20:36 -07003096
Haicheng Li4eaf3f62010-05-24 14:32:52 -07003097/*
3098 * Called with zonelists_mutex held always
3099 * unless system_state == SYSTEM_BOOTING.
3100 */
Haicheng Li1f522502010-05-24 14:32:51 -07003101void build_all_zonelists(void *data)
Yasunori Goto68113782006-06-23 02:03:11 -07003102{
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07003103 set_zonelist_order();
3104
Yasunori Goto68113782006-06-23 02:03:11 -07003105 if (system_state == SYSTEM_BOOTING) {
Randy Dunlap423b41d2006-09-27 01:50:12 -07003106 __build_all_zonelists(NULL);
Mel Gorman68ad8df2008-07-23 21:26:52 -07003107 mminit_verify_zonelist();
Yasunori Goto68113782006-06-23 02:03:11 -07003108 cpuset_init_current_mems_allowed();
3109 } else {
Simon Arlott183ff222007-10-20 01:27:18 +02003110 /* we have to stop all cpus to guarantee there is no user
Yasunori Goto68113782006-06-23 02:03:11 -07003111 of zonelist */
KAMEZAWA Hiroyukie9959f02010-11-24 12:57:09 -08003112#ifdef CONFIG_MEMORY_HOTPLUG
3113 if (data)
3114 setup_zone_pageset((struct zone *)data);
3115#endif
3116 stop_machine(__build_all_zonelists, NULL, NULL);
Yasunori Goto68113782006-06-23 02:03:11 -07003117 /* cpuset refresh routine should be here */
3118 }
Andrew Mortonbd1e22b2006-06-23 02:03:47 -07003119 vm_total_pages = nr_free_pagecache_pages();
Mel Gorman9ef9acb2007-10-16 01:25:54 -07003120 /*
3121 * Disable grouping by mobility if the number of pages in the
3122 * system is too low to allow the mechanism to work. It would be
3123 * more accurate, but expensive to check per-zone. This check is
3124 * made on memory-hotadd so a system can start with mobility
3125 * disabled and enable it later
3126 */
Mel Gormand9c23402007-10-16 01:26:01 -07003127 if (vm_total_pages < (pageblock_nr_pages * MIGRATE_TYPES))
Mel Gorman9ef9acb2007-10-16 01:25:54 -07003128 page_group_by_mobility_disabled = 1;
3129 else
3130 page_group_by_mobility_disabled = 0;
3131
3132 printk("Built %i zonelists in %s order, mobility grouping %s. "
3133 "Total pages: %ld\n",
Christoph Lameter62bc62a2009-06-16 15:32:15 -07003134 nr_online_nodes,
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07003135 zonelist_order_name[current_zonelist_order],
Mel Gorman9ef9acb2007-10-16 01:25:54 -07003136 page_group_by_mobility_disabled ? "off" : "on",
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07003137 vm_total_pages);
3138#ifdef CONFIG_NUMA
3139 printk("Policy zone: %s\n", zone_names[policy_zone]);
3140#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07003141}
3142
3143/*
3144 * Helper functions to size the waitqueue hash table.
3145 * Essentially these want to choose hash table sizes sufficiently
3146 * large so that collisions trying to wait on pages are rare.
3147 * But in fact, the number of active page waitqueues on typical
3148 * systems is ridiculously low, less than 200. So this is even
3149 * conservative, even though it seems large.
3150 *
3151 * The constant PAGES_PER_WAITQUEUE specifies the ratio of pages to
3152 * waitqueues, i.e. the size of the waitq table given the number of pages.
3153 */
3154#define PAGES_PER_WAITQUEUE 256
3155
Yasunori Gotocca448f2006-06-23 02:03:10 -07003156#ifndef CONFIG_MEMORY_HOTPLUG
Yasunori Goto02b694d2006-06-23 02:03:08 -07003157static inline unsigned long wait_table_hash_nr_entries(unsigned long pages)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003158{
3159 unsigned long size = 1;
3160
3161 pages /= PAGES_PER_WAITQUEUE;
3162
3163 while (size < pages)
3164 size <<= 1;
3165
3166 /*
3167 * Once we have dozens or even hundreds of threads sleeping
3168 * on IO we've got bigger problems than wait queue collision.
3169 * Limit the size of the wait table to a reasonable size.
3170 */
3171 size = min(size, 4096UL);
3172
3173 return max(size, 4UL);
3174}
Yasunori Gotocca448f2006-06-23 02:03:10 -07003175#else
3176/*
3177 * A zone's size might be changed by hot-add, so it is not possible to determine
3178 * a suitable size for its wait_table. So we use the maximum size now.
3179 *
3180 * The max wait table size = 4096 x sizeof(wait_queue_head_t). ie:
3181 *
3182 * i386 (preemption config) : 4096 x 16 = 64Kbyte.
3183 * ia64, x86-64 (no preemption): 4096 x 20 = 80Kbyte.
3184 * ia64, x86-64 (preemption) : 4096 x 24 = 96Kbyte.
3185 *
3186 * The maximum entries are prepared when a zone's memory is (512K + 256) pages
3187 * or more by the traditional way. (See above). It equals:
3188 *
3189 * i386, x86-64, powerpc(4K page size) : = ( 2G + 1M)byte.
3190 * ia64(16K page size) : = ( 8G + 4M)byte.
3191 * powerpc (64K page size) : = (32G +16M)byte.
3192 */
3193static inline unsigned long wait_table_hash_nr_entries(unsigned long pages)
3194{
3195 return 4096UL;
3196}
3197#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07003198
3199/*
3200 * This is an integer logarithm so that shifts can be used later
3201 * to extract the more random high bits from the multiplicative
3202 * hash function before the remainder is taken.
3203 */
3204static inline unsigned long wait_table_bits(unsigned long size)
3205{
3206 return ffz(~size);
3207}
3208
3209#define LONG_ALIGN(x) (((x)+(sizeof(long))-1)&~((sizeof(long))-1))
3210
Mel Gorman56fd56b2007-10-16 01:25:58 -07003211/*
Mel Gormand9c23402007-10-16 01:26:01 -07003212 * Mark a number of pageblocks as MIGRATE_RESERVE. The number
Mel Gorman41858962009-06-16 15:32:12 -07003213 * of blocks reserved is based on min_wmark_pages(zone). The memory within
3214 * the reserve will tend to store contiguous free pages. Setting min_free_kbytes
Mel Gorman56fd56b2007-10-16 01:25:58 -07003215 * higher will lead to a bigger reserve which will get freed as contiguous
3216 * blocks as reclaim kicks in
3217 */
3218static void setup_zone_migrate_reserve(struct zone *zone)
3219{
3220 unsigned long start_pfn, pfn, end_pfn;
3221 struct page *page;
Mel Gorman78986a62009-09-21 17:03:02 -07003222 unsigned long block_migratetype;
3223 int reserve;
Mel Gorman56fd56b2007-10-16 01:25:58 -07003224
3225 /* Get the start pfn, end pfn and the number of blocks to reserve */
3226 start_pfn = zone->zone_start_pfn;
3227 end_pfn = start_pfn + zone->spanned_pages;
Mel Gorman41858962009-06-16 15:32:12 -07003228 reserve = roundup(min_wmark_pages(zone), pageblock_nr_pages) >>
Mel Gormand9c23402007-10-16 01:26:01 -07003229 pageblock_order;
Mel Gorman56fd56b2007-10-16 01:25:58 -07003230
Mel Gorman78986a62009-09-21 17:03:02 -07003231 /*
3232 * Reserve blocks are generally in place to help high-order atomic
3233 * allocations that are short-lived. A min_free_kbytes value that
3234 * would result in more than 2 reserve blocks for atomic allocations
3235 * is assumed to be in place to help anti-fragmentation for the
3236 * future allocation of hugepages at runtime.
3237 */
3238 reserve = min(2, reserve);
3239
Mel Gormand9c23402007-10-16 01:26:01 -07003240 for (pfn = start_pfn; pfn < end_pfn; pfn += pageblock_nr_pages) {
Mel Gorman56fd56b2007-10-16 01:25:58 -07003241 if (!pfn_valid(pfn))
3242 continue;
3243 page = pfn_to_page(pfn);
3244
Adam Litke344c7902008-09-02 14:35:38 -07003245 /* Watch out for overlapping nodes */
3246 if (page_to_nid(page) != zone_to_nid(zone))
3247 continue;
3248
Mel Gorman56fd56b2007-10-16 01:25:58 -07003249 /* Blocks with reserved pages will never free, skip them. */
3250 if (PageReserved(page))
3251 continue;
3252
3253 block_migratetype = get_pageblock_migratetype(page);
3254
3255 /* If this block is reserved, account for it */
3256 if (reserve > 0 && block_migratetype == MIGRATE_RESERVE) {
3257 reserve--;
3258 continue;
3259 }
3260
3261 /* Suitable for reserving if this block is movable */
3262 if (reserve > 0 && block_migratetype == MIGRATE_MOVABLE) {
3263 set_pageblock_migratetype(page, MIGRATE_RESERVE);
3264 move_freepages_block(zone, page, MIGRATE_RESERVE);
3265 reserve--;
3266 continue;
3267 }
3268
3269 /*
3270 * If the reserve is met and this is a previous reserved block,
3271 * take it back
3272 */
3273 if (block_migratetype == MIGRATE_RESERVE) {
3274 set_pageblock_migratetype(page, MIGRATE_MOVABLE);
3275 move_freepages_block(zone, page, MIGRATE_MOVABLE);
3276 }
3277 }
3278}
Mel Gormanac0e5b72007-10-16 01:25:58 -07003279
Linus Torvalds1da177e2005-04-16 15:20:36 -07003280/*
3281 * Initially all pages are reserved - free ones are freed
3282 * up by free_all_bootmem() once the early boot process is
3283 * done. Non-atomic initialization, single-pass.
3284 */
Matt Tolentinoc09b4242006-01-17 07:03:44 +01003285void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone,
Dave Hansena2f3aa02007-01-10 23:15:30 -08003286 unsigned long start_pfn, enum memmap_context context)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003287{
Linus Torvalds1da177e2005-04-16 15:20:36 -07003288 struct page *page;
Andy Whitcroft29751f62005-06-23 00:08:00 -07003289 unsigned long end_pfn = start_pfn + size;
3290 unsigned long pfn;
KAMEZAWA Hiroyuki86051ca2008-04-29 00:58:21 -07003291 struct zone *z;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003292
Hugh Dickins22b31ee2009-01-06 14:40:09 -08003293 if (highest_memmap_pfn < end_pfn - 1)
3294 highest_memmap_pfn = end_pfn - 1;
3295
KAMEZAWA Hiroyuki86051ca2008-04-29 00:58:21 -07003296 z = &NODE_DATA(nid)->node_zones[zone];
Greg Ungerercbe8dd42006-01-12 01:05:24 -08003297 for (pfn = start_pfn; pfn < end_pfn; pfn++) {
Dave Hansena2f3aa02007-01-10 23:15:30 -08003298 /*
3299 * There can be holes in boot-time mem_map[]s
3300 * handed to this function. They do not
3301 * exist on hotplugged memory.
3302 */
3303 if (context == MEMMAP_EARLY) {
3304 if (!early_pfn_valid(pfn))
3305 continue;
3306 if (!early_pfn_in_nid(pfn, nid))
3307 continue;
3308 }
Andy Whitcroftd41dee32005-06-23 00:07:54 -07003309 page = pfn_to_page(pfn);
3310 set_page_links(page, zone, nid, pfn);
Mel Gorman708614e2008-07-23 21:26:51 -07003311 mminit_verify_page_links(page, zone, nid, pfn);
Nick Piggin7835e982006-03-22 00:08:40 -08003312 init_page_count(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003313 reset_page_mapcount(page);
3314 SetPageReserved(page);
Mel Gormanb2a0ac82007-10-16 01:25:48 -07003315 /*
3316 * Mark the block movable so that blocks are reserved for
3317 * movable at startup. This will force kernel allocations
3318 * to reserve their blocks rather than leaking throughout
3319 * the address space during boot when many long-lived
Mel Gorman56fd56b2007-10-16 01:25:58 -07003320 * kernel allocations are made. Later some blocks near
3321 * the start are marked MIGRATE_RESERVE by
3322 * setup_zone_migrate_reserve()
KAMEZAWA Hiroyuki86051ca2008-04-29 00:58:21 -07003323 *
3324 * bitmap is created for zone's valid pfn range. but memmap
3325 * can be created for invalid pages (for alignment)
3326 * check here not to call set_pageblock_migratetype() against
3327 * pfn out of zone.
Mel Gormanb2a0ac82007-10-16 01:25:48 -07003328 */
KAMEZAWA Hiroyuki86051ca2008-04-29 00:58:21 -07003329 if ((z->zone_start_pfn <= pfn)
3330 && (pfn < z->zone_start_pfn + z->spanned_pages)
3331 && !(pfn & (pageblock_nr_pages - 1)))
Mel Gorman56fd56b2007-10-16 01:25:58 -07003332 set_pageblock_migratetype(page, MIGRATE_MOVABLE);
Mel Gormanb2a0ac82007-10-16 01:25:48 -07003333
Linus Torvalds1da177e2005-04-16 15:20:36 -07003334 INIT_LIST_HEAD(&page->lru);
3335#ifdef WANT_PAGE_VIRTUAL
3336 /* The shift won't overflow because ZONE_NORMAL is below 4G. */
3337 if (!is_highmem_idx(zone))
Bob Picco3212c6b2005-06-27 14:36:28 -07003338 set_page_address(page, __va(pfn << PAGE_SHIFT));
Linus Torvalds1da177e2005-04-16 15:20:36 -07003339#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07003340 }
3341}
3342
Andi Kleen1e548de2008-02-04 22:29:26 -08003343static void __meminit zone_init_free_lists(struct zone *zone)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003344{
Mel Gormanb2a0ac82007-10-16 01:25:48 -07003345 int order, t;
3346 for_each_migratetype_order(order, t) {
3347 INIT_LIST_HEAD(&zone->free_area[order].free_list[t]);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003348 zone->free_area[order].nr_free = 0;
3349 }
3350}
3351
3352#ifndef __HAVE_ARCH_MEMMAP_INIT
3353#define memmap_init(size, nid, zone, start_pfn) \
Dave Hansena2f3aa02007-01-10 23:15:30 -08003354 memmap_init_zone((size), (nid), (zone), (start_pfn), MEMMAP_EARLY)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003355#endif
3356
Sam Ravnborg1d6f4e62008-01-17 15:21:12 -08003357static int zone_batchsize(struct zone *zone)
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003358{
David Howells3a6be872009-05-06 16:03:03 -07003359#ifdef CONFIG_MMU
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003360 int batch;
3361
3362 /*
3363 * The per-cpu-pages pools are set to around 1000th of the
Seth, Rohitba56e912005-10-29 18:15:47 -07003364 * size of the zone. But no more than 1/2 of a meg.
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003365 *
3366 * OK, so we don't know how big the cache is. So guess.
3367 */
3368 batch = zone->present_pages / 1024;
Seth, Rohitba56e912005-10-29 18:15:47 -07003369 if (batch * PAGE_SIZE > 512 * 1024)
3370 batch = (512 * 1024) / PAGE_SIZE;
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003371 batch /= 4; /* We effectively *= 4 below */
3372 if (batch < 1)
3373 batch = 1;
3374
3375 /*
Nick Piggin0ceaacc2005-12-04 13:55:25 +11003376 * Clamp the batch to a 2^n - 1 value. Having a power
3377 * of 2 value was found to be more likely to have
3378 * suboptimal cache aliasing properties in some cases.
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003379 *
Nick Piggin0ceaacc2005-12-04 13:55:25 +11003380 * For example if 2 tasks are alternately allocating
3381 * batches of pages, one task can end up with a lot
3382 * of pages of one half of the possible page colors
3383 * and the other with pages of the other colors.
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003384 */
David Howells91552032009-05-06 16:03:02 -07003385 batch = rounddown_pow_of_two(batch + batch/2) - 1;
Seth, Rohitba56e912005-10-29 18:15:47 -07003386
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003387 return batch;
David Howells3a6be872009-05-06 16:03:03 -07003388
3389#else
3390 /* The deferral and batching of frees should be suppressed under NOMMU
3391 * conditions.
3392 *
3393 * The problem is that NOMMU needs to be able to allocate large chunks
3394 * of contiguous memory as there's no hardware page translation to
3395 * assemble apparent contiguous memory from discontiguous pages.
3396 *
3397 * Queueing large contiguous runs of pages for batching, however,
3398 * causes the pages to actually be freed in smaller chunks. As there
3399 * can be a significant delay between the individual batches being
3400 * recycled, this leads to the once large chunks of space being
3401 * fragmented and becoming unavailable for high-order allocations.
3402 */
3403 return 0;
3404#endif
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003405}
3406
Adrian Bunkb69a7282008-07-23 21:28:12 -07003407static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch)
Christoph Lameter2caaad42005-06-21 17:15:00 -07003408{
3409 struct per_cpu_pages *pcp;
Mel Gorman5f8dcc22009-09-21 17:03:19 -07003410 int migratetype;
Christoph Lameter2caaad42005-06-21 17:15:00 -07003411
Magnus Damm1c6fe942005-10-26 01:58:59 -07003412 memset(p, 0, sizeof(*p));
3413
Christoph Lameter3dfa5722008-02-04 22:29:19 -08003414 pcp = &p->pcp;
Christoph Lameter2caaad42005-06-21 17:15:00 -07003415 pcp->count = 0;
Christoph Lameter2caaad42005-06-21 17:15:00 -07003416 pcp->high = 6 * batch;
3417 pcp->batch = max(1UL, 1 * batch);
Mel Gorman5f8dcc22009-09-21 17:03:19 -07003418 for (migratetype = 0; migratetype < MIGRATE_PCPTYPES; migratetype++)
3419 INIT_LIST_HEAD(&pcp->lists[migratetype]);
Christoph Lameter2caaad42005-06-21 17:15:00 -07003420}
3421
Rohit Seth8ad4b1f2006-01-08 01:00:40 -08003422/*
3423 * setup_pagelist_highmark() sets the high water mark for hot per_cpu_pagelist
3424 * to the value high for the pageset p.
3425 */
3426
3427static void setup_pagelist_highmark(struct per_cpu_pageset *p,
3428 unsigned long high)
3429{
3430 struct per_cpu_pages *pcp;
3431
Christoph Lameter3dfa5722008-02-04 22:29:19 -08003432 pcp = &p->pcp;
Rohit Seth8ad4b1f2006-01-08 01:00:40 -08003433 pcp->high = high;
3434 pcp->batch = max(1UL, high/4);
3435 if ((high/4) > (PAGE_SHIFT * 8))
3436 pcp->batch = PAGE_SHIFT * 8;
3437}
3438
Wu Fengguang319774e2010-05-24 14:32:49 -07003439static __meminit void setup_zone_pageset(struct zone *zone)
3440{
3441 int cpu;
3442
3443 zone->pageset = alloc_percpu(struct per_cpu_pageset);
3444
3445 for_each_possible_cpu(cpu) {
3446 struct per_cpu_pageset *pcp = per_cpu_ptr(zone->pageset, cpu);
3447
3448 setup_pageset(pcp, zone_batchsize(zone));
3449
3450 if (percpu_pagelist_fraction)
3451 setup_pagelist_highmark(pcp,
3452 (zone->present_pages /
3453 percpu_pagelist_fraction));
3454 }
3455}
3456
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003457/*
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09003458 * Allocate per cpu pagesets and initialize them.
3459 * Before this call only boot pagesets were available.
Christoph Lameter2caaad42005-06-21 17:15:00 -07003460 */
Al Viro78d99552005-12-15 09:18:25 +00003461void __init setup_per_cpu_pageset(void)
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003462{
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09003463 struct zone *zone;
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003464
Wu Fengguang319774e2010-05-24 14:32:49 -07003465 for_each_populated_zone(zone)
3466 setup_zone_pageset(zone);
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003467}
3468
Sam Ravnborg577a32f2007-05-17 23:29:25 +02003469static noinline __init_refok
Yasunori Gotocca448f2006-06-23 02:03:10 -07003470int zone_wait_table_init(struct zone *zone, unsigned long zone_size_pages)
Dave Hansened8ece22005-10-29 18:16:50 -07003471{
3472 int i;
3473 struct pglist_data *pgdat = zone->zone_pgdat;
Yasunori Gotocca448f2006-06-23 02:03:10 -07003474 size_t alloc_size;
Dave Hansened8ece22005-10-29 18:16:50 -07003475
3476 /*
3477 * The per-page waitqueue mechanism uses hashed waitqueues
3478 * per zone.
3479 */
Yasunori Goto02b694d2006-06-23 02:03:08 -07003480 zone->wait_table_hash_nr_entries =
3481 wait_table_hash_nr_entries(zone_size_pages);
3482 zone->wait_table_bits =
3483 wait_table_bits(zone->wait_table_hash_nr_entries);
Yasunori Gotocca448f2006-06-23 02:03:10 -07003484 alloc_size = zone->wait_table_hash_nr_entries
3485 * sizeof(wait_queue_head_t);
3486
Heiko Carstenscd94b9d2008-05-23 13:04:52 -07003487 if (!slab_is_available()) {
Yasunori Gotocca448f2006-06-23 02:03:10 -07003488 zone->wait_table = (wait_queue_head_t *)
3489 alloc_bootmem_node(pgdat, alloc_size);
3490 } else {
3491 /*
3492 * This case means that a zone whose size was 0 gets new memory
3493 * via memory hot-add.
3494 * But it may be the case that a new node was hot-added. In
3495 * this case vmalloc() will not be able to use this new node's
3496 * memory - this wait_table must be initialized to use this new
3497 * node itself as well.
3498 * To use this new node's memory, further consideration will be
3499 * necessary.
3500 */
Jesper Juhl8691f3a2007-10-16 01:24:49 -07003501 zone->wait_table = vmalloc(alloc_size);
Yasunori Gotocca448f2006-06-23 02:03:10 -07003502 }
3503 if (!zone->wait_table)
3504 return -ENOMEM;
Dave Hansened8ece22005-10-29 18:16:50 -07003505
Yasunori Goto02b694d2006-06-23 02:03:08 -07003506 for(i = 0; i < zone->wait_table_hash_nr_entries; ++i)
Dave Hansened8ece22005-10-29 18:16:50 -07003507 init_waitqueue_head(zone->wait_table + i);
Yasunori Gotocca448f2006-06-23 02:03:10 -07003508
3509 return 0;
Dave Hansened8ece22005-10-29 18:16:50 -07003510}
3511
Shaohua Li112067f2009-09-21 17:01:16 -07003512static int __zone_pcp_update(void *data)
3513{
3514 struct zone *zone = data;
3515 int cpu;
3516 unsigned long batch = zone_batchsize(zone), flags;
3517
Thomas Gleixner2d30a1f2010-03-10 15:20:40 -08003518 for_each_possible_cpu(cpu) {
Shaohua Li112067f2009-09-21 17:01:16 -07003519 struct per_cpu_pageset *pset;
3520 struct per_cpu_pages *pcp;
3521
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09003522 pset = per_cpu_ptr(zone->pageset, cpu);
Shaohua Li112067f2009-09-21 17:01:16 -07003523 pcp = &pset->pcp;
3524
3525 local_irq_save(flags);
Mel Gorman5f8dcc22009-09-21 17:03:19 -07003526 free_pcppages_bulk(zone, pcp->count, pcp);
Shaohua Li112067f2009-09-21 17:01:16 -07003527 setup_pageset(pset, batch);
3528 local_irq_restore(flags);
3529 }
3530 return 0;
3531}
3532
3533void zone_pcp_update(struct zone *zone)
3534{
3535 stop_machine(__zone_pcp_update, zone, NULL);
3536}
3537
Matt Tolentinoc09b4242006-01-17 07:03:44 +01003538static __meminit void zone_pcp_init(struct zone *zone)
Dave Hansened8ece22005-10-29 18:16:50 -07003539{
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09003540 /*
3541 * per cpu subsystem is not up at this point. The following code
3542 * relies on the ability of the linker to provide the
3543 * offset of a (static) per cpu variable into the per cpu area.
3544 */
3545 zone->pageset = &boot_pageset;
Dave Hansened8ece22005-10-29 18:16:50 -07003546
Anton Blanchardf5335c02006-03-25 03:06:49 -08003547 if (zone->present_pages)
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09003548 printk(KERN_DEBUG " %s zone: %lu pages, LIFO batch:%u\n",
3549 zone->name, zone->present_pages,
3550 zone_batchsize(zone));
Dave Hansened8ece22005-10-29 18:16:50 -07003551}
3552
Yasunori Goto718127c2006-06-23 02:03:10 -07003553__meminit int init_currently_empty_zone(struct zone *zone,
3554 unsigned long zone_start_pfn,
Dave Hansena2f3aa02007-01-10 23:15:30 -08003555 unsigned long size,
3556 enum memmap_context context)
Dave Hansened8ece22005-10-29 18:16:50 -07003557{
3558 struct pglist_data *pgdat = zone->zone_pgdat;
Yasunori Gotocca448f2006-06-23 02:03:10 -07003559 int ret;
3560 ret = zone_wait_table_init(zone, size);
3561 if (ret)
3562 return ret;
Dave Hansened8ece22005-10-29 18:16:50 -07003563 pgdat->nr_zones = zone_idx(zone) + 1;
3564
Dave Hansened8ece22005-10-29 18:16:50 -07003565 zone->zone_start_pfn = zone_start_pfn;
3566
Mel Gorman708614e2008-07-23 21:26:51 -07003567 mminit_dprintk(MMINIT_TRACE, "memmap_init",
3568 "Initialising map node %d zone %lu pfns %lu -> %lu\n",
3569 pgdat->node_id,
3570 (unsigned long)zone_idx(zone),
3571 zone_start_pfn, (zone_start_pfn + size));
3572
Andi Kleen1e548de2008-02-04 22:29:26 -08003573 zone_init_free_lists(zone);
Yasunori Goto718127c2006-06-23 02:03:10 -07003574
3575 return 0;
Dave Hansened8ece22005-10-29 18:16:50 -07003576}
3577
Mel Gormanc7132162006-09-27 01:49:43 -07003578#ifdef CONFIG_ARCH_POPULATES_NODE_MAP
3579/*
3580 * Basic iterator support. Return the first range of PFNs for a node
3581 * Note: nid == MAX_NUMNODES returns first region regardless of node
3582 */
Yasunori Gotoa3142c82007-05-08 00:23:07 -07003583static int __meminit first_active_region_index_in_nid(int nid)
Mel Gormanc7132162006-09-27 01:49:43 -07003584{
3585 int i;
3586
3587 for (i = 0; i < nr_nodemap_entries; i++)
3588 if (nid == MAX_NUMNODES || early_node_map[i].nid == nid)
3589 return i;
3590
3591 return -1;
3592}
3593
3594/*
3595 * Basic iterator support. Return the next active range of PFNs for a node
Simon Arlott183ff222007-10-20 01:27:18 +02003596 * Note: nid == MAX_NUMNODES returns next region regardless of node
Mel Gormanc7132162006-09-27 01:49:43 -07003597 */
Yasunori Gotoa3142c82007-05-08 00:23:07 -07003598static int __meminit next_active_region_index_in_nid(int index, int nid)
Mel Gormanc7132162006-09-27 01:49:43 -07003599{
3600 for (index = index + 1; index < nr_nodemap_entries; index++)
3601 if (nid == MAX_NUMNODES || early_node_map[index].nid == nid)
3602 return index;
3603
3604 return -1;
3605}
3606
3607#ifndef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
3608/*
3609 * Required by SPARSEMEM. Given a PFN, return what node the PFN is on.
3610 * Architectures may implement their own version but if add_active_range()
3611 * was used and there are no special requirements, this is a convenient
3612 * alternative
3613 */
KAMEZAWA Hiroyukif2dbcfa2009-02-18 14:48:32 -08003614int __meminit __early_pfn_to_nid(unsigned long pfn)
Mel Gormanc7132162006-09-27 01:49:43 -07003615{
3616 int i;
3617
3618 for (i = 0; i < nr_nodemap_entries; i++) {
3619 unsigned long start_pfn = early_node_map[i].start_pfn;
3620 unsigned long end_pfn = early_node_map[i].end_pfn;
3621
3622 if (start_pfn <= pfn && pfn < end_pfn)
3623 return early_node_map[i].nid;
3624 }
KAMEZAWA Hiroyukicc2559b2009-02-18 14:48:33 -08003625 /* This is a memory hole */
3626 return -1;
Mel Gormanc7132162006-09-27 01:49:43 -07003627}
3628#endif /* CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID */
3629
KAMEZAWA Hiroyukif2dbcfa2009-02-18 14:48:32 -08003630int __meminit early_pfn_to_nid(unsigned long pfn)
3631{
KAMEZAWA Hiroyukicc2559b2009-02-18 14:48:33 -08003632 int nid;
3633
3634 nid = __early_pfn_to_nid(pfn);
3635 if (nid >= 0)
3636 return nid;
3637 /* just returns 0 */
3638 return 0;
KAMEZAWA Hiroyukif2dbcfa2009-02-18 14:48:32 -08003639}
3640
KAMEZAWA Hiroyukicc2559b2009-02-18 14:48:33 -08003641#ifdef CONFIG_NODES_SPAN_OTHER_NODES
3642bool __meminit early_pfn_in_nid(unsigned long pfn, int node)
3643{
3644 int nid;
3645
3646 nid = __early_pfn_to_nid(pfn);
3647 if (nid >= 0 && nid != node)
3648 return false;
3649 return true;
3650}
3651#endif
KAMEZAWA Hiroyukif2dbcfa2009-02-18 14:48:32 -08003652
Mel Gormanc7132162006-09-27 01:49:43 -07003653/* Basic iterator support to walk early_node_map[] */
3654#define for_each_active_range_index_in_nid(i, nid) \
3655 for (i = first_active_region_index_in_nid(nid); i != -1; \
3656 i = next_active_region_index_in_nid(i, nid))
3657
3658/**
3659 * free_bootmem_with_active_regions - Call free_bootmem_node for each active range
Randy Dunlap88ca3b92006-10-04 02:15:25 -07003660 * @nid: The node to free memory on. If MAX_NUMNODES, all nodes are freed.
3661 * @max_low_pfn: The highest PFN that will be passed to free_bootmem_node
Mel Gormanc7132162006-09-27 01:49:43 -07003662 *
3663 * If an architecture guarantees that all ranges registered with
3664 * add_active_ranges() contain no holes and may be freed, this
3665 * this function may be used instead of calling free_bootmem() manually.
3666 */
3667void __init free_bootmem_with_active_regions(int nid,
3668 unsigned long max_low_pfn)
3669{
3670 int i;
3671
3672 for_each_active_range_index_in_nid(i, nid) {
3673 unsigned long size_pages = 0;
3674 unsigned long end_pfn = early_node_map[i].end_pfn;
3675
3676 if (early_node_map[i].start_pfn >= max_low_pfn)
3677 continue;
3678
3679 if (end_pfn > max_low_pfn)
3680 end_pfn = max_low_pfn;
3681
3682 size_pages = end_pfn - early_node_map[i].start_pfn;
3683 free_bootmem_node(NODE_DATA(early_node_map[i].nid),
3684 PFN_PHYS(early_node_map[i].start_pfn),
3685 size_pages << PAGE_SHIFT);
3686 }
3687}
3688
Yinghai Luedbe7d22010-08-25 13:39:16 -07003689#ifdef CONFIG_HAVE_MEMBLOCK
3690u64 __init find_memory_core_early(int nid, u64 size, u64 align,
3691 u64 goal, u64 limit)
3692{
3693 int i;
3694
3695 /* Need to go over early_node_map to find out good range for node */
3696 for_each_active_range_index_in_nid(i, nid) {
3697 u64 addr;
3698 u64 ei_start, ei_last;
3699 u64 final_start, final_end;
3700
3701 ei_last = early_node_map[i].end_pfn;
3702 ei_last <<= PAGE_SHIFT;
3703 ei_start = early_node_map[i].start_pfn;
3704 ei_start <<= PAGE_SHIFT;
3705
3706 final_start = max(ei_start, goal);
3707 final_end = min(ei_last, limit);
3708
3709 if (final_start >= final_end)
3710 continue;
3711
3712 addr = memblock_find_in_range(final_start, final_end, size, align);
3713
3714 if (addr == MEMBLOCK_ERROR)
3715 continue;
3716
3717 return addr;
3718 }
3719
3720 return MEMBLOCK_ERROR;
3721}
3722#endif
3723
Yinghai Lu08677212010-02-10 01:20:20 -08003724int __init add_from_early_node_map(struct range *range, int az,
3725 int nr_range, int nid)
3726{
3727 int i;
3728 u64 start, end;
3729
3730 /* need to go over early_node_map to find out good range for node */
3731 for_each_active_range_index_in_nid(i, nid) {
3732 start = early_node_map[i].start_pfn;
3733 end = early_node_map[i].end_pfn;
3734 nr_range = add_range(range, az, nr_range, start, end);
3735 }
3736 return nr_range;
3737}
3738
Yinghai Lu2ee78f72010-02-17 11:29:49 -08003739#ifdef CONFIG_NO_BOOTMEM
Yinghai Lu08677212010-02-10 01:20:20 -08003740void * __init __alloc_memory_core_early(int nid, u64 size, u64 align,
3741 u64 goal, u64 limit)
3742{
Yinghai Lu08677212010-02-10 01:20:20 -08003743 void *ptr;
Yinghai Lu72d7c3b2010-08-25 13:39:17 -07003744 u64 addr;
Yinghai Lu08677212010-02-10 01:20:20 -08003745
Yinghai Lu72d7c3b2010-08-25 13:39:17 -07003746 if (limit > memblock.current_limit)
3747 limit = memblock.current_limit;
Yinghai Lub8ab9f82010-07-20 13:24:31 -07003748
Yinghai Lu72d7c3b2010-08-25 13:39:17 -07003749 addr = find_memory_core_early(nid, size, align, goal, limit);
Yinghai Lu08677212010-02-10 01:20:20 -08003750
Yinghai Lu72d7c3b2010-08-25 13:39:17 -07003751 if (addr == MEMBLOCK_ERROR)
3752 return NULL;
Yinghai Lu08677212010-02-10 01:20:20 -08003753
Yinghai Lu72d7c3b2010-08-25 13:39:17 -07003754 ptr = phys_to_virt(addr);
3755 memset(ptr, 0, size);
3756 memblock_x86_reserve_range(addr, addr + size, "BOOTMEM");
3757 /*
3758 * The min_count is set to 0 so that bootmem allocated blocks
3759 * are never reported as leaks.
3760 */
3761 kmemleak_alloc(ptr, size, 0, 0);
3762 return ptr;
Yinghai Lu08677212010-02-10 01:20:20 -08003763}
Yinghai Lu2ee78f72010-02-17 11:29:49 -08003764#endif
Yinghai Lu08677212010-02-10 01:20:20 -08003765
3766
Yinghai Lub5bc6c02008-06-14 18:32:52 -07003767void __init work_with_active_regions(int nid, work_fn_t work_fn, void *data)
3768{
3769 int i;
Yinghai Lud52d53b2008-06-16 20:10:55 -07003770 int ret;
Yinghai Lub5bc6c02008-06-14 18:32:52 -07003771
Yinghai Lud52d53b2008-06-16 20:10:55 -07003772 for_each_active_range_index_in_nid(i, nid) {
3773 ret = work_fn(early_node_map[i].start_pfn,
3774 early_node_map[i].end_pfn, data);
3775 if (ret)
3776 break;
3777 }
Yinghai Lub5bc6c02008-06-14 18:32:52 -07003778}
Mel Gormanc7132162006-09-27 01:49:43 -07003779/**
3780 * sparse_memory_present_with_active_regions - Call memory_present for each active range
Randy Dunlap88ca3b92006-10-04 02:15:25 -07003781 * @nid: The node to call memory_present for. If MAX_NUMNODES, all nodes will be used.
Mel Gormanc7132162006-09-27 01:49:43 -07003782 *
3783 * If an architecture guarantees that all ranges registered with
3784 * add_active_ranges() contain no holes and may be freed, this
Randy Dunlap88ca3b92006-10-04 02:15:25 -07003785 * function may be used instead of calling memory_present() manually.
Mel Gormanc7132162006-09-27 01:49:43 -07003786 */
3787void __init sparse_memory_present_with_active_regions(int nid)
3788{
3789 int i;
3790
3791 for_each_active_range_index_in_nid(i, nid)
3792 memory_present(early_node_map[i].nid,
3793 early_node_map[i].start_pfn,
3794 early_node_map[i].end_pfn);
3795}
3796
3797/**
3798 * get_pfn_range_for_nid - Return the start and end page frames for a node
Randy Dunlap88ca3b92006-10-04 02:15:25 -07003799 * @nid: The nid to return the range for. If MAX_NUMNODES, the min and max PFN are returned.
3800 * @start_pfn: Passed by reference. On return, it will have the node start_pfn.
3801 * @end_pfn: Passed by reference. On return, it will have the node end_pfn.
Mel Gormanc7132162006-09-27 01:49:43 -07003802 *
3803 * It returns the start and end page frame of a node based on information
3804 * provided by an arch calling add_active_range(). If called for a node
3805 * with no available memory, a warning is printed and the start and end
Randy Dunlap88ca3b92006-10-04 02:15:25 -07003806 * PFNs will be 0.
Mel Gormanc7132162006-09-27 01:49:43 -07003807 */
Yasunori Gotoa3142c82007-05-08 00:23:07 -07003808void __meminit get_pfn_range_for_nid(unsigned int nid,
Mel Gormanc7132162006-09-27 01:49:43 -07003809 unsigned long *start_pfn, unsigned long *end_pfn)
3810{
3811 int i;
3812 *start_pfn = -1UL;
3813 *end_pfn = 0;
3814
3815 for_each_active_range_index_in_nid(i, nid) {
3816 *start_pfn = min(*start_pfn, early_node_map[i].start_pfn);
3817 *end_pfn = max(*end_pfn, early_node_map[i].end_pfn);
3818 }
3819
Christoph Lameter633c0662007-10-16 01:25:37 -07003820 if (*start_pfn == -1UL)
Mel Gormanc7132162006-09-27 01:49:43 -07003821 *start_pfn = 0;
Mel Gormanc7132162006-09-27 01:49:43 -07003822}
3823
3824/*
Mel Gorman2a1e2742007-07-17 04:03:12 -07003825 * This finds a zone that can be used for ZONE_MOVABLE pages. The
3826 * assumption is made that zones within a node are ordered in monotonic
3827 * increasing memory addresses so that the "highest" populated zone is used
3828 */
Adrian Bunkb69a7282008-07-23 21:28:12 -07003829static void __init find_usable_zone_for_movable(void)
Mel Gorman2a1e2742007-07-17 04:03:12 -07003830{
3831 int zone_index;
3832 for (zone_index = MAX_NR_ZONES - 1; zone_index >= 0; zone_index--) {
3833 if (zone_index == ZONE_MOVABLE)
3834 continue;
3835
3836 if (arch_zone_highest_possible_pfn[zone_index] >
3837 arch_zone_lowest_possible_pfn[zone_index])
3838 break;
3839 }
3840
3841 VM_BUG_ON(zone_index == -1);
3842 movable_zone = zone_index;
3843}
3844
3845/*
3846 * The zone ranges provided by the architecture do not include ZONE_MOVABLE
3847 * because it is sized independant of architecture. Unlike the other zones,
3848 * the starting point for ZONE_MOVABLE is not fixed. It may be different
3849 * in each node depending on the size of each node and how evenly kernelcore
3850 * is distributed. This helper function adjusts the zone ranges
3851 * provided by the architecture for a given node by using the end of the
3852 * highest usable zone for ZONE_MOVABLE. This preserves the assumption that
3853 * zones within a node are in order of monotonic increases memory addresses
3854 */
Adrian Bunkb69a7282008-07-23 21:28:12 -07003855static void __meminit adjust_zone_range_for_zone_movable(int nid,
Mel Gorman2a1e2742007-07-17 04:03:12 -07003856 unsigned long zone_type,
3857 unsigned long node_start_pfn,
3858 unsigned long node_end_pfn,
3859 unsigned long *zone_start_pfn,
3860 unsigned long *zone_end_pfn)
3861{
3862 /* Only adjust if ZONE_MOVABLE is on this node */
3863 if (zone_movable_pfn[nid]) {
3864 /* Size ZONE_MOVABLE */
3865 if (zone_type == ZONE_MOVABLE) {
3866 *zone_start_pfn = zone_movable_pfn[nid];
3867 *zone_end_pfn = min(node_end_pfn,
3868 arch_zone_highest_possible_pfn[movable_zone]);
3869
3870 /* Adjust for ZONE_MOVABLE starting within this range */
3871 } else if (*zone_start_pfn < zone_movable_pfn[nid] &&
3872 *zone_end_pfn > zone_movable_pfn[nid]) {
3873 *zone_end_pfn = zone_movable_pfn[nid];
3874
3875 /* Check if this whole range is within ZONE_MOVABLE */
3876 } else if (*zone_start_pfn >= zone_movable_pfn[nid])
3877 *zone_start_pfn = *zone_end_pfn;
3878 }
3879}
3880
3881/*
Mel Gormanc7132162006-09-27 01:49:43 -07003882 * Return the number of pages a zone spans in a node, including holes
3883 * present_pages = zone_spanned_pages_in_node() - zone_absent_pages_in_node()
3884 */
Paul Mundt6ea6e682007-07-15 23:38:20 -07003885static unsigned long __meminit zone_spanned_pages_in_node(int nid,
Mel Gormanc7132162006-09-27 01:49:43 -07003886 unsigned long zone_type,
3887 unsigned long *ignored)
3888{
3889 unsigned long node_start_pfn, node_end_pfn;
3890 unsigned long zone_start_pfn, zone_end_pfn;
3891
3892 /* Get the start and end of the node and zone */
3893 get_pfn_range_for_nid(nid, &node_start_pfn, &node_end_pfn);
3894 zone_start_pfn = arch_zone_lowest_possible_pfn[zone_type];
3895 zone_end_pfn = arch_zone_highest_possible_pfn[zone_type];
Mel Gorman2a1e2742007-07-17 04:03:12 -07003896 adjust_zone_range_for_zone_movable(nid, zone_type,
3897 node_start_pfn, node_end_pfn,
3898 &zone_start_pfn, &zone_end_pfn);
Mel Gormanc7132162006-09-27 01:49:43 -07003899
3900 /* Check that this node has pages within the zone's required range */
3901 if (zone_end_pfn < node_start_pfn || zone_start_pfn > node_end_pfn)
3902 return 0;
3903
3904 /* Move the zone boundaries inside the node if necessary */
3905 zone_end_pfn = min(zone_end_pfn, node_end_pfn);
3906 zone_start_pfn = max(zone_start_pfn, node_start_pfn);
3907
3908 /* Return the spanned pages */
3909 return zone_end_pfn - zone_start_pfn;
3910}
3911
3912/*
3913 * Return the number of holes in a range on a node. If nid is MAX_NUMNODES,
Randy Dunlap88ca3b92006-10-04 02:15:25 -07003914 * then all holes in the requested range will be accounted for.
Mel Gormanc7132162006-09-27 01:49:43 -07003915 */
Yinghai Lu32996252009-12-15 17:59:02 -08003916unsigned long __meminit __absent_pages_in_range(int nid,
Mel Gormanc7132162006-09-27 01:49:43 -07003917 unsigned long range_start_pfn,
3918 unsigned long range_end_pfn)
3919{
3920 int i = 0;
3921 unsigned long prev_end_pfn = 0, hole_pages = 0;
3922 unsigned long start_pfn;
3923
3924 /* Find the end_pfn of the first active range of pfns in the node */
3925 i = first_active_region_index_in_nid(nid);
3926 if (i == -1)
3927 return 0;
3928
Mel Gormanb5445f92007-07-26 10:41:18 -07003929 prev_end_pfn = min(early_node_map[i].start_pfn, range_end_pfn);
3930
Mel Gorman9c7cd682006-09-27 01:49:58 -07003931 /* Account for ranges before physical memory on this node */
3932 if (early_node_map[i].start_pfn > range_start_pfn)
Mel Gormanb5445f92007-07-26 10:41:18 -07003933 hole_pages = prev_end_pfn - range_start_pfn;
Mel Gormanc7132162006-09-27 01:49:43 -07003934
3935 /* Find all holes for the zone within the node */
3936 for (; i != -1; i = next_active_region_index_in_nid(i, nid)) {
3937
3938 /* No need to continue if prev_end_pfn is outside the zone */
3939 if (prev_end_pfn >= range_end_pfn)
3940 break;
3941
3942 /* Make sure the end of the zone is not within the hole */
3943 start_pfn = min(early_node_map[i].start_pfn, range_end_pfn);
3944 prev_end_pfn = max(prev_end_pfn, range_start_pfn);
3945
3946 /* Update the hole size cound and move on */
3947 if (start_pfn > range_start_pfn) {
3948 BUG_ON(prev_end_pfn > start_pfn);
3949 hole_pages += start_pfn - prev_end_pfn;
3950 }
3951 prev_end_pfn = early_node_map[i].end_pfn;
3952 }
3953
Mel Gorman9c7cd682006-09-27 01:49:58 -07003954 /* Account for ranges past physical memory on this node */
3955 if (range_end_pfn > prev_end_pfn)
Mel Gorman0c6cb972006-10-28 10:38:59 -07003956 hole_pages += range_end_pfn -
Mel Gorman9c7cd682006-09-27 01:49:58 -07003957 max(range_start_pfn, prev_end_pfn);
3958
Mel Gormanc7132162006-09-27 01:49:43 -07003959 return hole_pages;
3960}
3961
3962/**
3963 * absent_pages_in_range - Return number of page frames in holes within a range
3964 * @start_pfn: The start PFN to start searching for holes
3965 * @end_pfn: The end PFN to stop searching for holes
3966 *
Randy Dunlap88ca3b92006-10-04 02:15:25 -07003967 * It returns the number of pages frames in memory holes within a range.
Mel Gormanc7132162006-09-27 01:49:43 -07003968 */
3969unsigned long __init absent_pages_in_range(unsigned long start_pfn,
3970 unsigned long end_pfn)
3971{
3972 return __absent_pages_in_range(MAX_NUMNODES, start_pfn, end_pfn);
3973}
3974
3975/* Return the number of page frames in holes in a zone on a node */
Paul Mundt6ea6e682007-07-15 23:38:20 -07003976static unsigned long __meminit zone_absent_pages_in_node(int nid,
Mel Gormanc7132162006-09-27 01:49:43 -07003977 unsigned long zone_type,
3978 unsigned long *ignored)
3979{
Mel Gorman9c7cd682006-09-27 01:49:58 -07003980 unsigned long node_start_pfn, node_end_pfn;
3981 unsigned long zone_start_pfn, zone_end_pfn;
3982
3983 get_pfn_range_for_nid(nid, &node_start_pfn, &node_end_pfn);
3984 zone_start_pfn = max(arch_zone_lowest_possible_pfn[zone_type],
3985 node_start_pfn);
3986 zone_end_pfn = min(arch_zone_highest_possible_pfn[zone_type],
3987 node_end_pfn);
3988
Mel Gorman2a1e2742007-07-17 04:03:12 -07003989 adjust_zone_range_for_zone_movable(nid, zone_type,
3990 node_start_pfn, node_end_pfn,
3991 &zone_start_pfn, &zone_end_pfn);
Mel Gorman9c7cd682006-09-27 01:49:58 -07003992 return __absent_pages_in_range(nid, zone_start_pfn, zone_end_pfn);
Mel Gormanc7132162006-09-27 01:49:43 -07003993}
Mel Gorman0e0b8642006-09-27 01:49:56 -07003994
Mel Gormanc7132162006-09-27 01:49:43 -07003995#else
Paul Mundt6ea6e682007-07-15 23:38:20 -07003996static inline unsigned long __meminit zone_spanned_pages_in_node(int nid,
Mel Gormanc7132162006-09-27 01:49:43 -07003997 unsigned long zone_type,
3998 unsigned long *zones_size)
3999{
4000 return zones_size[zone_type];
4001}
4002
Paul Mundt6ea6e682007-07-15 23:38:20 -07004003static inline unsigned long __meminit zone_absent_pages_in_node(int nid,
Mel Gormanc7132162006-09-27 01:49:43 -07004004 unsigned long zone_type,
4005 unsigned long *zholes_size)
4006{
4007 if (!zholes_size)
4008 return 0;
4009
4010 return zholes_size[zone_type];
4011}
Mel Gorman0e0b8642006-09-27 01:49:56 -07004012
Mel Gormanc7132162006-09-27 01:49:43 -07004013#endif
4014
Yasunori Gotoa3142c82007-05-08 00:23:07 -07004015static void __meminit calculate_node_totalpages(struct pglist_data *pgdat,
Mel Gormanc7132162006-09-27 01:49:43 -07004016 unsigned long *zones_size, unsigned long *zholes_size)
4017{
4018 unsigned long realtotalpages, totalpages = 0;
4019 enum zone_type i;
4020
4021 for (i = 0; i < MAX_NR_ZONES; i++)
4022 totalpages += zone_spanned_pages_in_node(pgdat->node_id, i,
4023 zones_size);
4024 pgdat->node_spanned_pages = totalpages;
4025
4026 realtotalpages = totalpages;
4027 for (i = 0; i < MAX_NR_ZONES; i++)
4028 realtotalpages -=
4029 zone_absent_pages_in_node(pgdat->node_id, i,
4030 zholes_size);
4031 pgdat->node_present_pages = realtotalpages;
4032 printk(KERN_DEBUG "On node %d totalpages: %lu\n", pgdat->node_id,
4033 realtotalpages);
4034}
4035
Mel Gorman835c1342007-10-16 01:25:47 -07004036#ifndef CONFIG_SPARSEMEM
4037/*
4038 * Calculate the size of the zone->blockflags rounded to an unsigned long
Mel Gormand9c23402007-10-16 01:26:01 -07004039 * Start by making sure zonesize is a multiple of pageblock_order by rounding
4040 * up. Then use 1 NR_PAGEBLOCK_BITS worth of bits per pageblock, finally
Mel Gorman835c1342007-10-16 01:25:47 -07004041 * round what is now in bits to nearest long in bits, then return it in
4042 * bytes.
4043 */
4044static unsigned long __init usemap_size(unsigned long zonesize)
4045{
4046 unsigned long usemapsize;
4047
Mel Gormand9c23402007-10-16 01:26:01 -07004048 usemapsize = roundup(zonesize, pageblock_nr_pages);
4049 usemapsize = usemapsize >> pageblock_order;
Mel Gorman835c1342007-10-16 01:25:47 -07004050 usemapsize *= NR_PAGEBLOCK_BITS;
4051 usemapsize = roundup(usemapsize, 8 * sizeof(unsigned long));
4052
4053 return usemapsize / 8;
4054}
4055
4056static void __init setup_usemap(struct pglist_data *pgdat,
4057 struct zone *zone, unsigned long zonesize)
4058{
4059 unsigned long usemapsize = usemap_size(zonesize);
4060 zone->pageblock_flags = NULL;
Julia Lawall58a01a42009-01-06 14:39:28 -08004061 if (usemapsize)
Mel Gorman835c1342007-10-16 01:25:47 -07004062 zone->pageblock_flags = alloc_bootmem_node(pgdat, usemapsize);
Mel Gorman835c1342007-10-16 01:25:47 -07004063}
4064#else
Jesper Juhlfa9f90b2010-11-28 21:39:34 +01004065static inline void setup_usemap(struct pglist_data *pgdat,
Mel Gorman835c1342007-10-16 01:25:47 -07004066 struct zone *zone, unsigned long zonesize) {}
4067#endif /* CONFIG_SPARSEMEM */
4068
Mel Gormand9c23402007-10-16 01:26:01 -07004069#ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
Mel Gormanba72cb82007-11-28 16:21:13 -08004070
4071/* Return a sensible default order for the pageblock size. */
4072static inline int pageblock_default_order(void)
4073{
4074 if (HPAGE_SHIFT > PAGE_SHIFT)
4075 return HUGETLB_PAGE_ORDER;
4076
4077 return MAX_ORDER-1;
4078}
4079
Mel Gormand9c23402007-10-16 01:26:01 -07004080/* Initialise the number of pages represented by NR_PAGEBLOCK_BITS */
4081static inline void __init set_pageblock_order(unsigned int order)
4082{
4083 /* Check that pageblock_nr_pages has not already been setup */
4084 if (pageblock_order)
4085 return;
4086
4087 /*
4088 * Assume the largest contiguous order of interest is a huge page.
4089 * This value may be variable depending on boot parameters on IA64
4090 */
4091 pageblock_order = order;
4092}
4093#else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
4094
Mel Gormanba72cb82007-11-28 16:21:13 -08004095/*
4096 * When CONFIG_HUGETLB_PAGE_SIZE_VARIABLE is not set, set_pageblock_order()
4097 * and pageblock_default_order() are unused as pageblock_order is set
4098 * at compile-time. See include/linux/pageblock-flags.h for the values of
4099 * pageblock_order based on the kernel config
4100 */
4101static inline int pageblock_default_order(unsigned int order)
4102{
4103 return MAX_ORDER-1;
4104}
Mel Gormand9c23402007-10-16 01:26:01 -07004105#define set_pageblock_order(x) do {} while (0)
4106
4107#endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
4108
Linus Torvalds1da177e2005-04-16 15:20:36 -07004109/*
4110 * Set up the zone data structures:
4111 * - mark all pages reserved
4112 * - mark all memory queues empty
4113 * - clear the memory bitmaps
4114 */
Alexander van Heukelumb5a0e012008-02-23 15:24:06 -08004115static void __paginginit free_area_init_core(struct pglist_data *pgdat,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004116 unsigned long *zones_size, unsigned long *zholes_size)
4117{
Christoph Lameter2f1b6242006-09-25 23:31:13 -07004118 enum zone_type j;
Dave Hansened8ece22005-10-29 18:16:50 -07004119 int nid = pgdat->node_id;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004120 unsigned long zone_start_pfn = pgdat->node_start_pfn;
Yasunori Goto718127c2006-06-23 02:03:10 -07004121 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004122
Dave Hansen208d54e2005-10-29 18:16:52 -07004123 pgdat_resize_init(pgdat);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004124 pgdat->nr_zones = 0;
4125 init_waitqueue_head(&pgdat->kswapd_wait);
4126 pgdat->kswapd_max_order = 0;
KAMEZAWA Hiroyuki52d4b9a2008-10-18 20:28:16 -07004127 pgdat_page_cgroup_init(pgdat);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004128
4129 for (j = 0; j < MAX_NR_ZONES; j++) {
4130 struct zone *zone = pgdat->node_zones + j;
Mel Gorman0e0b8642006-09-27 01:49:56 -07004131 unsigned long size, realsize, memmap_pages;
Christoph Lameterb69408e2008-10-18 20:26:14 -07004132 enum lru_list l;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004133
Mel Gormanc7132162006-09-27 01:49:43 -07004134 size = zone_spanned_pages_in_node(nid, j, zones_size);
4135 realsize = size - zone_absent_pages_in_node(nid, j,
4136 zholes_size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004137
Mel Gorman0e0b8642006-09-27 01:49:56 -07004138 /*
4139 * Adjust realsize so that it accounts for how much memory
4140 * is used by this zone for memmap. This affects the watermark
4141 * and per-cpu initialisations
4142 */
Johannes Weinerf7232152008-05-23 13:04:21 -07004143 memmap_pages =
4144 PAGE_ALIGN(size * sizeof(struct page)) >> PAGE_SHIFT;
Mel Gorman0e0b8642006-09-27 01:49:56 -07004145 if (realsize >= memmap_pages) {
4146 realsize -= memmap_pages;
Yinghai Lu5594c8c2009-01-06 14:39:14 -08004147 if (memmap_pages)
4148 printk(KERN_DEBUG
4149 " %s zone: %lu pages used for memmap\n",
4150 zone_names[j], memmap_pages);
Mel Gorman0e0b8642006-09-27 01:49:56 -07004151 } else
4152 printk(KERN_WARNING
4153 " %s zone: %lu pages exceeds realsize %lu\n",
4154 zone_names[j], memmap_pages, realsize);
4155
Christoph Lameter62672762007-02-10 01:43:07 -08004156 /* Account for reserved pages */
4157 if (j == 0 && realsize > dma_reserve) {
Mel Gorman0e0b8642006-09-27 01:49:56 -07004158 realsize -= dma_reserve;
Yinghai Lud903ef92008-10-18 20:27:06 -07004159 printk(KERN_DEBUG " %s zone: %lu pages reserved\n",
Christoph Lameter62672762007-02-10 01:43:07 -08004160 zone_names[0], dma_reserve);
Mel Gorman0e0b8642006-09-27 01:49:56 -07004161 }
4162
Christoph Lameter98d2b0e2006-09-25 23:31:12 -07004163 if (!is_highmem_idx(j))
Linus Torvalds1da177e2005-04-16 15:20:36 -07004164 nr_kernel_pages += realsize;
4165 nr_all_pages += realsize;
4166
4167 zone->spanned_pages = size;
4168 zone->present_pages = realsize;
Christoph Lameter96146342006-07-03 00:24:13 -07004169#ifdef CONFIG_NUMA
Christoph Lameterd5f541e2006-09-27 01:50:08 -07004170 zone->node = nid;
Christoph Lameter8417bba2006-09-25 23:31:51 -07004171 zone->min_unmapped_pages = (realsize*sysctl_min_unmapped_ratio)
Christoph Lameter96146342006-07-03 00:24:13 -07004172 / 100;
Christoph Lameter0ff38492006-09-25 23:31:52 -07004173 zone->min_slab_pages = (realsize * sysctl_min_slab_ratio) / 100;
Christoph Lameter96146342006-07-03 00:24:13 -07004174#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07004175 zone->name = zone_names[j];
4176 spin_lock_init(&zone->lock);
4177 spin_lock_init(&zone->lru_lock);
Dave Hansenbdc8cb92005-10-29 18:16:53 -07004178 zone_seqlock_init(zone);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004179 zone->zone_pgdat = pgdat;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004180
Dave Hansened8ece22005-10-29 18:16:50 -07004181 zone_pcp_init(zone);
Christoph Lameterb69408e2008-10-18 20:26:14 -07004182 for_each_lru(l) {
4183 INIT_LIST_HEAD(&zone->lru[l].list);
Wu Fengguangf8629632009-09-21 17:03:11 -07004184 zone->reclaim_stat.nr_saved_scan[l] = 0;
Christoph Lameterb69408e2008-10-18 20:26:14 -07004185 }
KOSAKI Motohiro6e901572009-01-07 18:08:15 -08004186 zone->reclaim_stat.recent_rotated[0] = 0;
4187 zone->reclaim_stat.recent_rotated[1] = 0;
4188 zone->reclaim_stat.recent_scanned[0] = 0;
4189 zone->reclaim_stat.recent_scanned[1] = 0;
Christoph Lameter2244b952006-06-30 01:55:33 -07004190 zap_zone_vm_stats(zone);
David Rientjese815af92007-10-16 23:25:54 -07004191 zone->flags = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004192 if (!size)
4193 continue;
4194
Mel Gormanba72cb82007-11-28 16:21:13 -08004195 set_pageblock_order(pageblock_default_order());
Mel Gorman835c1342007-10-16 01:25:47 -07004196 setup_usemap(pgdat, zone, size);
Dave Hansena2f3aa02007-01-10 23:15:30 -08004197 ret = init_currently_empty_zone(zone, zone_start_pfn,
4198 size, MEMMAP_EARLY);
Yasunori Goto718127c2006-06-23 02:03:10 -07004199 BUG_ON(ret);
Heiko Carstens76cdd582008-05-14 16:05:52 -07004200 memmap_init(size, nid, j, zone_start_pfn);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004201 zone_start_pfn += size;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004202 }
4203}
4204
Sam Ravnborg577a32f2007-05-17 23:29:25 +02004205static void __init_refok alloc_node_mem_map(struct pglist_data *pgdat)
Linus Torvalds1da177e2005-04-16 15:20:36 -07004206{
Linus Torvalds1da177e2005-04-16 15:20:36 -07004207 /* Skip empty nodes */
4208 if (!pgdat->node_spanned_pages)
4209 return;
4210
Andy Whitcroftd41dee32005-06-23 00:07:54 -07004211#ifdef CONFIG_FLAT_NODE_MEM_MAP
Linus Torvalds1da177e2005-04-16 15:20:36 -07004212 /* ia64 gets its own node_mem_map, before this, without bootmem */
4213 if (!pgdat->node_mem_map) {
Bob Piccoe984bb42006-05-20 15:00:31 -07004214 unsigned long size, start, end;
Andy Whitcroftd41dee32005-06-23 00:07:54 -07004215 struct page *map;
4216
Bob Piccoe984bb42006-05-20 15:00:31 -07004217 /*
4218 * The zone's endpoints aren't required to be MAX_ORDER
4219 * aligned but the node_mem_map endpoints must be in order
4220 * for the buddy allocator to function correctly.
4221 */
4222 start = pgdat->node_start_pfn & ~(MAX_ORDER_NR_PAGES - 1);
4223 end = pgdat->node_start_pfn + pgdat->node_spanned_pages;
4224 end = ALIGN(end, MAX_ORDER_NR_PAGES);
4225 size = (end - start) * sizeof(struct page);
Dave Hansen6f167ec2005-06-23 00:07:39 -07004226 map = alloc_remap(pgdat->node_id, size);
4227 if (!map)
4228 map = alloc_bootmem_node(pgdat, size);
Bob Piccoe984bb42006-05-20 15:00:31 -07004229 pgdat->node_mem_map = map + (pgdat->node_start_pfn - start);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004230 }
Roman Zippel12d810c2007-05-31 00:40:54 -07004231#ifndef CONFIG_NEED_MULTIPLE_NODES
Linus Torvalds1da177e2005-04-16 15:20:36 -07004232 /*
4233 * With no DISCONTIG, the global mem_map is just set as node 0's
4234 */
Mel Gormanc7132162006-09-27 01:49:43 -07004235 if (pgdat == NODE_DATA(0)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07004236 mem_map = NODE_DATA(0)->node_mem_map;
Mel Gormanc7132162006-09-27 01:49:43 -07004237#ifdef CONFIG_ARCH_POPULATES_NODE_MAP
4238 if (page_to_pfn(mem_map) != pgdat->node_start_pfn)
Thomas Bogendoerfer467bc462008-01-08 15:33:11 -08004239 mem_map -= (pgdat->node_start_pfn - ARCH_PFN_OFFSET);
Mel Gormanc7132162006-09-27 01:49:43 -07004240#endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
4241 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07004242#endif
Andy Whitcroftd41dee32005-06-23 00:07:54 -07004243#endif /* CONFIG_FLAT_NODE_MEM_MAP */
Linus Torvalds1da177e2005-04-16 15:20:36 -07004244}
4245
Johannes Weiner9109fb72008-07-23 21:27:20 -07004246void __paginginit free_area_init_node(int nid, unsigned long *zones_size,
4247 unsigned long node_start_pfn, unsigned long *zholes_size)
Linus Torvalds1da177e2005-04-16 15:20:36 -07004248{
Johannes Weiner9109fb72008-07-23 21:27:20 -07004249 pg_data_t *pgdat = NODE_DATA(nid);
4250
Linus Torvalds1da177e2005-04-16 15:20:36 -07004251 pgdat->node_id = nid;
4252 pgdat->node_start_pfn = node_start_pfn;
Mel Gormanc7132162006-09-27 01:49:43 -07004253 calculate_node_totalpages(pgdat, zones_size, zholes_size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004254
4255 alloc_node_mem_map(pgdat);
Yinghai Lue8c27ac2008-06-01 13:15:22 -07004256#ifdef CONFIG_FLAT_NODE_MEM_MAP
4257 printk(KERN_DEBUG "free_area_init_node: node %d, pgdat %08lx, node_mem_map %08lx\n",
4258 nid, (unsigned long)pgdat,
4259 (unsigned long)pgdat->node_mem_map);
4260#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07004261
4262 free_area_init_core(pgdat, zones_size, zholes_size);
4263}
4264
Mel Gormanc7132162006-09-27 01:49:43 -07004265#ifdef CONFIG_ARCH_POPULATES_NODE_MAP
Miklos Szeredi418508c2007-05-23 13:57:55 -07004266
4267#if MAX_NUMNODES > 1
4268/*
4269 * Figure out the number of possible node ids.
4270 */
4271static void __init setup_nr_node_ids(void)
4272{
4273 unsigned int node;
4274 unsigned int highest = 0;
4275
4276 for_each_node_mask(node, node_possible_map)
4277 highest = node;
4278 nr_node_ids = highest + 1;
4279}
4280#else
4281static inline void setup_nr_node_ids(void)
4282{
4283}
4284#endif
4285
Mel Gormanc7132162006-09-27 01:49:43 -07004286/**
4287 * add_active_range - Register a range of PFNs backed by physical memory
4288 * @nid: The node ID the range resides on
4289 * @start_pfn: The start PFN of the available physical memory
4290 * @end_pfn: The end PFN of the available physical memory
4291 *
4292 * These ranges are stored in an early_node_map[] and later used by
4293 * free_area_init_nodes() to calculate zone sizes and holes. If the
4294 * range spans a memory hole, it is up to the architecture to ensure
4295 * the memory is not freed by the bootmem allocator. If possible
4296 * the range being registered will be merged with existing ranges.
4297 */
4298void __init add_active_range(unsigned int nid, unsigned long start_pfn,
4299 unsigned long end_pfn)
4300{
4301 int i;
4302
Mel Gorman6b74ab92008-07-23 21:26:49 -07004303 mminit_dprintk(MMINIT_TRACE, "memory_register",
4304 "Entering add_active_range(%d, %#lx, %#lx) "
4305 "%d entries of %d used\n",
4306 nid, start_pfn, end_pfn,
4307 nr_nodemap_entries, MAX_ACTIVE_REGIONS);
Mel Gormanc7132162006-09-27 01:49:43 -07004308
Mel Gorman2dbb51c2008-07-23 21:26:52 -07004309 mminit_validate_memmodel_limits(&start_pfn, &end_pfn);
4310
Mel Gormanc7132162006-09-27 01:49:43 -07004311 /* Merge with existing active regions if possible */
4312 for (i = 0; i < nr_nodemap_entries; i++) {
4313 if (early_node_map[i].nid != nid)
4314 continue;
4315
4316 /* Skip if an existing region covers this new one */
4317 if (start_pfn >= early_node_map[i].start_pfn &&
4318 end_pfn <= early_node_map[i].end_pfn)
4319 return;
4320
4321 /* Merge forward if suitable */
4322 if (start_pfn <= early_node_map[i].end_pfn &&
4323 end_pfn > early_node_map[i].end_pfn) {
4324 early_node_map[i].end_pfn = end_pfn;
4325 return;
4326 }
4327
4328 /* Merge backward if suitable */
Kazuhisa Ichikawad2dbe082010-01-15 17:01:20 -08004329 if (start_pfn < early_node_map[i].start_pfn &&
Mel Gormanc7132162006-09-27 01:49:43 -07004330 end_pfn >= early_node_map[i].start_pfn) {
4331 early_node_map[i].start_pfn = start_pfn;
4332 return;
4333 }
4334 }
4335
4336 /* Check that early_node_map is large enough */
4337 if (i >= MAX_ACTIVE_REGIONS) {
4338 printk(KERN_CRIT "More than %d memory regions, truncating\n",
4339 MAX_ACTIVE_REGIONS);
4340 return;
4341 }
4342
4343 early_node_map[i].nid = nid;
4344 early_node_map[i].start_pfn = start_pfn;
4345 early_node_map[i].end_pfn = end_pfn;
4346 nr_nodemap_entries = i + 1;
4347}
4348
4349/**
Yinghai Lucc1050b2008-06-13 19:08:52 -07004350 * remove_active_range - Shrink an existing registered range of PFNs
Mel Gormanc7132162006-09-27 01:49:43 -07004351 * @nid: The node id the range is on that should be shrunk
Yinghai Lucc1050b2008-06-13 19:08:52 -07004352 * @start_pfn: The new PFN of the range
4353 * @end_pfn: The new PFN of the range
Mel Gormanc7132162006-09-27 01:49:43 -07004354 *
4355 * i386 with NUMA use alloc_remap() to store a node_mem_map on a local node.
Yinghai Lucc1a9d82008-06-08 19:39:16 -07004356 * The map is kept near the end physical page range that has already been
4357 * registered. This function allows an arch to shrink an existing registered
4358 * range.
Mel Gormanc7132162006-09-27 01:49:43 -07004359 */
Yinghai Lucc1050b2008-06-13 19:08:52 -07004360void __init remove_active_range(unsigned int nid, unsigned long start_pfn,
4361 unsigned long end_pfn)
Mel Gormanc7132162006-09-27 01:49:43 -07004362{
Yinghai Lucc1a9d82008-06-08 19:39:16 -07004363 int i, j;
4364 int removed = 0;
Mel Gormanc7132162006-09-27 01:49:43 -07004365
Yinghai Lucc1050b2008-06-13 19:08:52 -07004366 printk(KERN_DEBUG "remove_active_range (%d, %lu, %lu)\n",
4367 nid, start_pfn, end_pfn);
4368
Mel Gormanc7132162006-09-27 01:49:43 -07004369 /* Find the old active region end and shrink */
Yinghai Lucc1a9d82008-06-08 19:39:16 -07004370 for_each_active_range_index_in_nid(i, nid) {
Yinghai Lucc1050b2008-06-13 19:08:52 -07004371 if (early_node_map[i].start_pfn >= start_pfn &&
4372 early_node_map[i].end_pfn <= end_pfn) {
Yinghai Lucc1a9d82008-06-08 19:39:16 -07004373 /* clear it */
Yinghai Lucc1050b2008-06-13 19:08:52 -07004374 early_node_map[i].start_pfn = 0;
Yinghai Lucc1a9d82008-06-08 19:39:16 -07004375 early_node_map[i].end_pfn = 0;
4376 removed = 1;
4377 continue;
Mel Gormanc7132162006-09-27 01:49:43 -07004378 }
Yinghai Lucc1050b2008-06-13 19:08:52 -07004379 if (early_node_map[i].start_pfn < start_pfn &&
4380 early_node_map[i].end_pfn > start_pfn) {
4381 unsigned long temp_end_pfn = early_node_map[i].end_pfn;
4382 early_node_map[i].end_pfn = start_pfn;
4383 if (temp_end_pfn > end_pfn)
4384 add_active_range(nid, end_pfn, temp_end_pfn);
4385 continue;
4386 }
4387 if (early_node_map[i].start_pfn >= start_pfn &&
4388 early_node_map[i].end_pfn > end_pfn &&
4389 early_node_map[i].start_pfn < end_pfn) {
4390 early_node_map[i].start_pfn = end_pfn;
Yinghai Lucc1a9d82008-06-08 19:39:16 -07004391 continue;
4392 }
4393 }
4394
4395 if (!removed)
4396 return;
4397
4398 /* remove the blank ones */
4399 for (i = nr_nodemap_entries - 1; i > 0; i--) {
4400 if (early_node_map[i].nid != nid)
4401 continue;
4402 if (early_node_map[i].end_pfn)
4403 continue;
4404 /* we found it, get rid of it */
4405 for (j = i; j < nr_nodemap_entries - 1; j++)
4406 memcpy(&early_node_map[j], &early_node_map[j+1],
4407 sizeof(early_node_map[j]));
4408 j = nr_nodemap_entries - 1;
4409 memset(&early_node_map[j], 0, sizeof(early_node_map[j]));
4410 nr_nodemap_entries--;
4411 }
Mel Gormanc7132162006-09-27 01:49:43 -07004412}
4413
4414/**
4415 * remove_all_active_ranges - Remove all currently registered regions
Randy Dunlap88ca3b92006-10-04 02:15:25 -07004416 *
Mel Gormanc7132162006-09-27 01:49:43 -07004417 * During discovery, it may be found that a table like SRAT is invalid
4418 * and an alternative discovery method must be used. This function removes
4419 * all currently registered regions.
4420 */
Randy Dunlap88ca3b92006-10-04 02:15:25 -07004421void __init remove_all_active_ranges(void)
Mel Gormanc7132162006-09-27 01:49:43 -07004422{
4423 memset(early_node_map, 0, sizeof(early_node_map));
4424 nr_nodemap_entries = 0;
4425}
4426
4427/* Compare two active node_active_regions */
4428static int __init cmp_node_active_region(const void *a, const void *b)
4429{
4430 struct node_active_region *arange = (struct node_active_region *)a;
4431 struct node_active_region *brange = (struct node_active_region *)b;
4432
4433 /* Done this way to avoid overflows */
4434 if (arange->start_pfn > brange->start_pfn)
4435 return 1;
4436 if (arange->start_pfn < brange->start_pfn)
4437 return -1;
4438
4439 return 0;
4440}
4441
4442/* sort the node_map by start_pfn */
Yinghai Lu32996252009-12-15 17:59:02 -08004443void __init sort_node_map(void)
Mel Gormanc7132162006-09-27 01:49:43 -07004444{
4445 sort(early_node_map, (size_t)nr_nodemap_entries,
4446 sizeof(struct node_active_region),
4447 cmp_node_active_region, NULL);
4448}
4449
Mel Gormana6af2bc2007-02-10 01:42:57 -08004450/* Find the lowest pfn for a node */
Adrian Bunkb69a7282008-07-23 21:28:12 -07004451static unsigned long __init find_min_pfn_for_node(int nid)
Mel Gormanc7132162006-09-27 01:49:43 -07004452{
4453 int i;
Mel Gormana6af2bc2007-02-10 01:42:57 -08004454 unsigned long min_pfn = ULONG_MAX;
Mel Gorman1abbfb42006-11-23 12:01:41 +00004455
Mel Gormanc7132162006-09-27 01:49:43 -07004456 /* Assuming a sorted map, the first range found has the starting pfn */
4457 for_each_active_range_index_in_nid(i, nid)
Mel Gormana6af2bc2007-02-10 01:42:57 -08004458 min_pfn = min(min_pfn, early_node_map[i].start_pfn);
Mel Gormanc7132162006-09-27 01:49:43 -07004459
Mel Gormana6af2bc2007-02-10 01:42:57 -08004460 if (min_pfn == ULONG_MAX) {
4461 printk(KERN_WARNING
Paul Jackson2bc0d262008-06-22 07:22:17 -07004462 "Could not find start_pfn for node %d\n", nid);
Mel Gormana6af2bc2007-02-10 01:42:57 -08004463 return 0;
4464 }
4465
4466 return min_pfn;
Mel Gormanc7132162006-09-27 01:49:43 -07004467}
4468
4469/**
4470 * find_min_pfn_with_active_regions - Find the minimum PFN registered
4471 *
4472 * It returns the minimum PFN based on information provided via
Randy Dunlap88ca3b92006-10-04 02:15:25 -07004473 * add_active_range().
Mel Gormanc7132162006-09-27 01:49:43 -07004474 */
4475unsigned long __init find_min_pfn_with_active_regions(void)
4476{
4477 return find_min_pfn_for_node(MAX_NUMNODES);
4478}
4479
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07004480/*
4481 * early_calculate_totalpages()
4482 * Sum pages in active regions for movable zone.
4483 * Populate N_HIGH_MEMORY for calculating usable_nodes.
4484 */
Adrian Bunk484f51f2007-10-16 01:26:03 -07004485static unsigned long __init early_calculate_totalpages(void)
Mel Gorman7e63efe2007-07-17 04:03:15 -07004486{
4487 int i;
4488 unsigned long totalpages = 0;
4489
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07004490 for (i = 0; i < nr_nodemap_entries; i++) {
4491 unsigned long pages = early_node_map[i].end_pfn -
Mel Gorman7e63efe2007-07-17 04:03:15 -07004492 early_node_map[i].start_pfn;
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07004493 totalpages += pages;
4494 if (pages)
4495 node_set_state(early_node_map[i].nid, N_HIGH_MEMORY);
4496 }
4497 return totalpages;
Mel Gorman7e63efe2007-07-17 04:03:15 -07004498}
4499
Mel Gorman2a1e2742007-07-17 04:03:12 -07004500/*
4501 * Find the PFN the Movable zone begins in each node. Kernel memory
4502 * is spread evenly between nodes as long as the nodes have enough
4503 * memory. When they don't, some nodes will have more kernelcore than
4504 * others
4505 */
Adrian Bunkb69a7282008-07-23 21:28:12 -07004506static void __init find_zone_movable_pfns_for_nodes(unsigned long *movable_pfn)
Mel Gorman2a1e2742007-07-17 04:03:12 -07004507{
4508 int i, nid;
4509 unsigned long usable_startpfn;
4510 unsigned long kernelcore_node, kernelcore_remaining;
Yinghai Lu66918dc2009-06-30 11:41:37 -07004511 /* save the state before borrow the nodemask */
4512 nodemask_t saved_node_state = node_states[N_HIGH_MEMORY];
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07004513 unsigned long totalpages = early_calculate_totalpages();
4514 int usable_nodes = nodes_weight(node_states[N_HIGH_MEMORY]);
Mel Gorman2a1e2742007-07-17 04:03:12 -07004515
Mel Gorman7e63efe2007-07-17 04:03:15 -07004516 /*
4517 * If movablecore was specified, calculate what size of
4518 * kernelcore that corresponds so that memory usable for
4519 * any allocation type is evenly spread. If both kernelcore
4520 * and movablecore are specified, then the value of kernelcore
4521 * will be used for required_kernelcore if it's greater than
4522 * what movablecore would have allowed.
4523 */
4524 if (required_movablecore) {
Mel Gorman7e63efe2007-07-17 04:03:15 -07004525 unsigned long corepages;
4526
4527 /*
4528 * Round-up so that ZONE_MOVABLE is at least as large as what
4529 * was requested by the user
4530 */
4531 required_movablecore =
4532 roundup(required_movablecore, MAX_ORDER_NR_PAGES);
4533 corepages = totalpages - required_movablecore;
4534
4535 required_kernelcore = max(required_kernelcore, corepages);
4536 }
4537
Mel Gorman2a1e2742007-07-17 04:03:12 -07004538 /* If kernelcore was not specified, there is no ZONE_MOVABLE */
4539 if (!required_kernelcore)
Yinghai Lu66918dc2009-06-30 11:41:37 -07004540 goto out;
Mel Gorman2a1e2742007-07-17 04:03:12 -07004541
4542 /* usable_startpfn is the lowest possible pfn ZONE_MOVABLE can be at */
4543 find_usable_zone_for_movable();
4544 usable_startpfn = arch_zone_lowest_possible_pfn[movable_zone];
4545
4546restart:
4547 /* Spread kernelcore memory as evenly as possible throughout nodes */
4548 kernelcore_node = required_kernelcore / usable_nodes;
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07004549 for_each_node_state(nid, N_HIGH_MEMORY) {
Mel Gorman2a1e2742007-07-17 04:03:12 -07004550 /*
4551 * Recalculate kernelcore_node if the division per node
4552 * now exceeds what is necessary to satisfy the requested
4553 * amount of memory for the kernel
4554 */
4555 if (required_kernelcore < kernelcore_node)
4556 kernelcore_node = required_kernelcore / usable_nodes;
4557
4558 /*
4559 * As the map is walked, we track how much memory is usable
4560 * by the kernel using kernelcore_remaining. When it is
4561 * 0, the rest of the node is usable by ZONE_MOVABLE
4562 */
4563 kernelcore_remaining = kernelcore_node;
4564
4565 /* Go through each range of PFNs within this node */
4566 for_each_active_range_index_in_nid(i, nid) {
4567 unsigned long start_pfn, end_pfn;
4568 unsigned long size_pages;
4569
4570 start_pfn = max(early_node_map[i].start_pfn,
4571 zone_movable_pfn[nid]);
4572 end_pfn = early_node_map[i].end_pfn;
4573 if (start_pfn >= end_pfn)
4574 continue;
4575
4576 /* Account for what is only usable for kernelcore */
4577 if (start_pfn < usable_startpfn) {
4578 unsigned long kernel_pages;
4579 kernel_pages = min(end_pfn, usable_startpfn)
4580 - start_pfn;
4581
4582 kernelcore_remaining -= min(kernel_pages,
4583 kernelcore_remaining);
4584 required_kernelcore -= min(kernel_pages,
4585 required_kernelcore);
4586
4587 /* Continue if range is now fully accounted */
4588 if (end_pfn <= usable_startpfn) {
4589
4590 /*
4591 * Push zone_movable_pfn to the end so
4592 * that if we have to rebalance
4593 * kernelcore across nodes, we will
4594 * not double account here
4595 */
4596 zone_movable_pfn[nid] = end_pfn;
4597 continue;
4598 }
4599 start_pfn = usable_startpfn;
4600 }
4601
4602 /*
4603 * The usable PFN range for ZONE_MOVABLE is from
4604 * start_pfn->end_pfn. Calculate size_pages as the
4605 * number of pages used as kernelcore
4606 */
4607 size_pages = end_pfn - start_pfn;
4608 if (size_pages > kernelcore_remaining)
4609 size_pages = kernelcore_remaining;
4610 zone_movable_pfn[nid] = start_pfn + size_pages;
4611
4612 /*
4613 * Some kernelcore has been met, update counts and
4614 * break if the kernelcore for this node has been
4615 * satisified
4616 */
4617 required_kernelcore -= min(required_kernelcore,
4618 size_pages);
4619 kernelcore_remaining -= size_pages;
4620 if (!kernelcore_remaining)
4621 break;
4622 }
4623 }
4624
4625 /*
4626 * If there is still required_kernelcore, we do another pass with one
4627 * less node in the count. This will push zone_movable_pfn[nid] further
4628 * along on the nodes that still have memory until kernelcore is
4629 * satisified
4630 */
4631 usable_nodes--;
4632 if (usable_nodes && required_kernelcore > usable_nodes)
4633 goto restart;
4634
4635 /* Align start of ZONE_MOVABLE on all nids to MAX_ORDER_NR_PAGES */
4636 for (nid = 0; nid < MAX_NUMNODES; nid++)
4637 zone_movable_pfn[nid] =
4638 roundup(zone_movable_pfn[nid], MAX_ORDER_NR_PAGES);
Yinghai Lu66918dc2009-06-30 11:41:37 -07004639
4640out:
4641 /* restore the node_state */
4642 node_states[N_HIGH_MEMORY] = saved_node_state;
Mel Gorman2a1e2742007-07-17 04:03:12 -07004643}
4644
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07004645/* Any regular memory on that node ? */
4646static void check_for_regular_memory(pg_data_t *pgdat)
4647{
4648#ifdef CONFIG_HIGHMEM
4649 enum zone_type zone_type;
4650
4651 for (zone_type = 0; zone_type <= ZONE_NORMAL; zone_type++) {
4652 struct zone *zone = &pgdat->node_zones[zone_type];
4653 if (zone->present_pages)
4654 node_set_state(zone_to_nid(zone), N_NORMAL_MEMORY);
4655 }
4656#endif
4657}
4658
Mel Gormanc7132162006-09-27 01:49:43 -07004659/**
4660 * free_area_init_nodes - Initialise all pg_data_t and zone data
Randy Dunlap88ca3b92006-10-04 02:15:25 -07004661 * @max_zone_pfn: an array of max PFNs for each zone
Mel Gormanc7132162006-09-27 01:49:43 -07004662 *
4663 * This will call free_area_init_node() for each active node in the system.
4664 * Using the page ranges provided by add_active_range(), the size of each
4665 * zone in each node and their holes is calculated. If the maximum PFN
4666 * between two adjacent zones match, it is assumed that the zone is empty.
4667 * For example, if arch_max_dma_pfn == arch_max_dma32_pfn, it is assumed
4668 * that arch_max_dma32_pfn has no pages. It is also assumed that a zone
4669 * starts where the previous one ended. For example, ZONE_DMA32 starts
4670 * at arch_max_dma_pfn.
4671 */
4672void __init free_area_init_nodes(unsigned long *max_zone_pfn)
4673{
4674 unsigned long nid;
Andrew Mortondb991002008-10-15 22:01:07 -07004675 int i;
Mel Gormanc7132162006-09-27 01:49:43 -07004676
Mel Gormana6af2bc2007-02-10 01:42:57 -08004677 /* Sort early_node_map as initialisation assumes it is sorted */
4678 sort_node_map();
4679
Mel Gormanc7132162006-09-27 01:49:43 -07004680 /* Record where the zone boundaries are */
4681 memset(arch_zone_lowest_possible_pfn, 0,
4682 sizeof(arch_zone_lowest_possible_pfn));
4683 memset(arch_zone_highest_possible_pfn, 0,
4684 sizeof(arch_zone_highest_possible_pfn));
4685 arch_zone_lowest_possible_pfn[0] = find_min_pfn_with_active_regions();
4686 arch_zone_highest_possible_pfn[0] = max_zone_pfn[0];
4687 for (i = 1; i < MAX_NR_ZONES; i++) {
Mel Gorman2a1e2742007-07-17 04:03:12 -07004688 if (i == ZONE_MOVABLE)
4689 continue;
Mel Gormanc7132162006-09-27 01:49:43 -07004690 arch_zone_lowest_possible_pfn[i] =
4691 arch_zone_highest_possible_pfn[i-1];
4692 arch_zone_highest_possible_pfn[i] =
4693 max(max_zone_pfn[i], arch_zone_lowest_possible_pfn[i]);
4694 }
Mel Gorman2a1e2742007-07-17 04:03:12 -07004695 arch_zone_lowest_possible_pfn[ZONE_MOVABLE] = 0;
4696 arch_zone_highest_possible_pfn[ZONE_MOVABLE] = 0;
4697
4698 /* Find the PFNs that ZONE_MOVABLE begins at in each node */
4699 memset(zone_movable_pfn, 0, sizeof(zone_movable_pfn));
4700 find_zone_movable_pfns_for_nodes(zone_movable_pfn);
Mel Gormanc7132162006-09-27 01:49:43 -07004701
Mel Gormanc7132162006-09-27 01:49:43 -07004702 /* Print out the zone ranges */
4703 printk("Zone PFN ranges:\n");
Mel Gorman2a1e2742007-07-17 04:03:12 -07004704 for (i = 0; i < MAX_NR_ZONES; i++) {
4705 if (i == ZONE_MOVABLE)
4706 continue;
David Rientjes72f0ba02010-03-05 13:42:14 -08004707 printk(" %-8s ", zone_names[i]);
4708 if (arch_zone_lowest_possible_pfn[i] ==
4709 arch_zone_highest_possible_pfn[i])
4710 printk("empty\n");
4711 else
4712 printk("%0#10lx -> %0#10lx\n",
Mel Gormanc7132162006-09-27 01:49:43 -07004713 arch_zone_lowest_possible_pfn[i],
4714 arch_zone_highest_possible_pfn[i]);
Mel Gorman2a1e2742007-07-17 04:03:12 -07004715 }
4716
4717 /* Print out the PFNs ZONE_MOVABLE begins at in each node */
4718 printk("Movable zone start PFN for each node\n");
4719 for (i = 0; i < MAX_NUMNODES; i++) {
4720 if (zone_movable_pfn[i])
4721 printk(" Node %d: %lu\n", i, zone_movable_pfn[i]);
4722 }
Mel Gormanc7132162006-09-27 01:49:43 -07004723
4724 /* Print out the early_node_map[] */
4725 printk("early_node_map[%d] active PFN ranges\n", nr_nodemap_entries);
4726 for (i = 0; i < nr_nodemap_entries; i++)
Paul Jackson5dab8ec2008-06-25 05:44:40 -07004727 printk(" %3d: %0#10lx -> %0#10lx\n", early_node_map[i].nid,
Mel Gormanc7132162006-09-27 01:49:43 -07004728 early_node_map[i].start_pfn,
4729 early_node_map[i].end_pfn);
4730
4731 /* Initialise every node */
Mel Gorman708614e2008-07-23 21:26:51 -07004732 mminit_verify_pageflags_layout();
Christoph Lameter8ef82862007-02-20 13:57:52 -08004733 setup_nr_node_ids();
Mel Gormanc7132162006-09-27 01:49:43 -07004734 for_each_online_node(nid) {
4735 pg_data_t *pgdat = NODE_DATA(nid);
Johannes Weiner9109fb72008-07-23 21:27:20 -07004736 free_area_init_node(nid, NULL,
Mel Gormanc7132162006-09-27 01:49:43 -07004737 find_min_pfn_for_node(nid), NULL);
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07004738
4739 /* Any memory on that node */
4740 if (pgdat->node_present_pages)
4741 node_set_state(nid, N_HIGH_MEMORY);
4742 check_for_regular_memory(pgdat);
Mel Gormanc7132162006-09-27 01:49:43 -07004743 }
4744}
Mel Gorman2a1e2742007-07-17 04:03:12 -07004745
Mel Gorman7e63efe2007-07-17 04:03:15 -07004746static int __init cmdline_parse_core(char *p, unsigned long *core)
Mel Gorman2a1e2742007-07-17 04:03:12 -07004747{
4748 unsigned long long coremem;
4749 if (!p)
4750 return -EINVAL;
4751
4752 coremem = memparse(p, &p);
Mel Gorman7e63efe2007-07-17 04:03:15 -07004753 *core = coremem >> PAGE_SHIFT;
Mel Gorman2a1e2742007-07-17 04:03:12 -07004754
Mel Gorman7e63efe2007-07-17 04:03:15 -07004755 /* Paranoid check that UL is enough for the coremem value */
Mel Gorman2a1e2742007-07-17 04:03:12 -07004756 WARN_ON((coremem >> PAGE_SHIFT) > ULONG_MAX);
4757
4758 return 0;
4759}
Mel Gormaned7ed362007-07-17 04:03:14 -07004760
Mel Gorman7e63efe2007-07-17 04:03:15 -07004761/*
4762 * kernelcore=size sets the amount of memory for use for allocations that
4763 * cannot be reclaimed or migrated.
4764 */
4765static int __init cmdline_parse_kernelcore(char *p)
4766{
4767 return cmdline_parse_core(p, &required_kernelcore);
4768}
4769
4770/*
4771 * movablecore=size sets the amount of memory for use for allocations that
4772 * can be reclaimed or migrated.
4773 */
4774static int __init cmdline_parse_movablecore(char *p)
4775{
4776 return cmdline_parse_core(p, &required_movablecore);
4777}
4778
Mel Gormaned7ed362007-07-17 04:03:14 -07004779early_param("kernelcore", cmdline_parse_kernelcore);
Mel Gorman7e63efe2007-07-17 04:03:15 -07004780early_param("movablecore", cmdline_parse_movablecore);
Mel Gormaned7ed362007-07-17 04:03:14 -07004781
Mel Gormanc7132162006-09-27 01:49:43 -07004782#endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
4783
Mel Gorman0e0b8642006-09-27 01:49:56 -07004784/**
Randy Dunlap88ca3b92006-10-04 02:15:25 -07004785 * set_dma_reserve - set the specified number of pages reserved in the first zone
4786 * @new_dma_reserve: The number of pages to mark reserved
Mel Gorman0e0b8642006-09-27 01:49:56 -07004787 *
4788 * The per-cpu batchsize and zone watermarks are determined by present_pages.
4789 * In the DMA zone, a significant percentage may be consumed by kernel image
4790 * and other unfreeable allocations which can skew the watermarks badly. This
Randy Dunlap88ca3b92006-10-04 02:15:25 -07004791 * function may optionally be used to account for unfreeable pages in the
4792 * first zone (e.g., ZONE_DMA). The effect will be lower watermarks and
4793 * smaller per-cpu batchsize.
Mel Gorman0e0b8642006-09-27 01:49:56 -07004794 */
4795void __init set_dma_reserve(unsigned long new_dma_reserve)
4796{
4797 dma_reserve = new_dma_reserve;
4798}
4799
Dave Hansen93b75042005-06-23 00:07:47 -07004800#ifndef CONFIG_NEED_MULTIPLE_NODES
Yinghai Lu08677212010-02-10 01:20:20 -08004801struct pglist_data __refdata contig_page_data = {
4802#ifndef CONFIG_NO_BOOTMEM
4803 .bdata = &bootmem_node_data[0]
4804#endif
4805 };
Linus Torvalds1da177e2005-04-16 15:20:36 -07004806EXPORT_SYMBOL(contig_page_data);
Dave Hansen93b75042005-06-23 00:07:47 -07004807#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07004808
4809void __init free_area_init(unsigned long *zones_size)
4810{
Johannes Weiner9109fb72008-07-23 21:27:20 -07004811 free_area_init_node(0, zones_size,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004812 __pa(PAGE_OFFSET) >> PAGE_SHIFT, NULL);
4813}
Linus Torvalds1da177e2005-04-16 15:20:36 -07004814
Linus Torvalds1da177e2005-04-16 15:20:36 -07004815static int page_alloc_cpu_notify(struct notifier_block *self,
4816 unsigned long action, void *hcpu)
4817{
4818 int cpu = (unsigned long)hcpu;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004819
Rafael J. Wysocki8bb78442007-05-09 02:35:10 -07004820 if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) {
Christoph Lameter9f8f2172008-02-04 22:29:11 -08004821 drain_pages(cpu);
4822
4823 /*
4824 * Spill the event counters of the dead processor
4825 * into the current processors event counters.
4826 * This artificially elevates the count of the current
4827 * processor.
4828 */
Christoph Lameterf8891e52006-06-30 01:55:45 -07004829 vm_events_fold_cpu(cpu);
Christoph Lameter9f8f2172008-02-04 22:29:11 -08004830
4831 /*
4832 * Zero the differential counters of the dead processor
4833 * so that the vm statistics are consistent.
4834 *
4835 * This is only okay since the processor is dead and cannot
4836 * race with what we are doing.
4837 */
Christoph Lameter2244b952006-06-30 01:55:33 -07004838 refresh_cpu_vm_stats(cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004839 }
4840 return NOTIFY_OK;
4841}
Linus Torvalds1da177e2005-04-16 15:20:36 -07004842
4843void __init page_alloc_init(void)
4844{
4845 hotcpu_notifier(page_alloc_cpu_notify, 0);
4846}
4847
4848/*
Hideo AOKIcb45b0e2006-04-10 22:52:59 -07004849 * calculate_totalreserve_pages - called when sysctl_lower_zone_reserve_ratio
4850 * or min_free_kbytes changes.
4851 */
4852static void calculate_totalreserve_pages(void)
4853{
4854 struct pglist_data *pgdat;
4855 unsigned long reserve_pages = 0;
Christoph Lameter2f6726e2006-09-25 23:31:18 -07004856 enum zone_type i, j;
Hideo AOKIcb45b0e2006-04-10 22:52:59 -07004857
4858 for_each_online_pgdat(pgdat) {
4859 for (i = 0; i < MAX_NR_ZONES; i++) {
4860 struct zone *zone = pgdat->node_zones + i;
4861 unsigned long max = 0;
4862
4863 /* Find valid and maximum lowmem_reserve in the zone */
4864 for (j = i; j < MAX_NR_ZONES; j++) {
4865 if (zone->lowmem_reserve[j] > max)
4866 max = zone->lowmem_reserve[j];
4867 }
4868
Mel Gorman41858962009-06-16 15:32:12 -07004869 /* we treat the high watermark as reserved pages. */
4870 max += high_wmark_pages(zone);
Hideo AOKIcb45b0e2006-04-10 22:52:59 -07004871
4872 if (max > zone->present_pages)
4873 max = zone->present_pages;
4874 reserve_pages += max;
4875 }
4876 }
4877 totalreserve_pages = reserve_pages;
4878}
4879
4880/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07004881 * setup_per_zone_lowmem_reserve - called whenever
4882 * sysctl_lower_zone_reserve_ratio changes. Ensures that each zone
4883 * has a correct pages reserved value, so an adequate number of
4884 * pages are left in the zone after a successful __alloc_pages().
4885 */
4886static void setup_per_zone_lowmem_reserve(void)
4887{
4888 struct pglist_data *pgdat;
Christoph Lameter2f6726e2006-09-25 23:31:18 -07004889 enum zone_type j, idx;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004890
KAMEZAWA Hiroyukiec936fc2006-03-27 01:15:59 -08004891 for_each_online_pgdat(pgdat) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07004892 for (j = 0; j < MAX_NR_ZONES; j++) {
4893 struct zone *zone = pgdat->node_zones + j;
4894 unsigned long present_pages = zone->present_pages;
4895
4896 zone->lowmem_reserve[j] = 0;
4897
Christoph Lameter2f6726e2006-09-25 23:31:18 -07004898 idx = j;
4899 while (idx) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07004900 struct zone *lower_zone;
4901
Christoph Lameter2f6726e2006-09-25 23:31:18 -07004902 idx--;
4903
Linus Torvalds1da177e2005-04-16 15:20:36 -07004904 if (sysctl_lowmem_reserve_ratio[idx] < 1)
4905 sysctl_lowmem_reserve_ratio[idx] = 1;
4906
4907 lower_zone = pgdat->node_zones + idx;
4908 lower_zone->lowmem_reserve[j] = present_pages /
4909 sysctl_lowmem_reserve_ratio[idx];
4910 present_pages += lower_zone->present_pages;
4911 }
4912 }
4913 }
Hideo AOKIcb45b0e2006-04-10 22:52:59 -07004914
4915 /* update totalreserve_pages */
4916 calculate_totalreserve_pages();
Linus Torvalds1da177e2005-04-16 15:20:36 -07004917}
4918
Randy Dunlap88ca3b92006-10-04 02:15:25 -07004919/**
Minchan Kimbc75d332009-06-16 15:32:48 -07004920 * setup_per_zone_wmarks - called when min_free_kbytes changes
Minchan Kimbce73942009-06-16 15:32:50 -07004921 * or when memory is hot-{added|removed}
Randy Dunlap88ca3b92006-10-04 02:15:25 -07004922 *
Minchan Kimbc75d332009-06-16 15:32:48 -07004923 * Ensures that the watermark[min,low,high] values for each zone are set
4924 * correctly with respect to min_free_kbytes.
Linus Torvalds1da177e2005-04-16 15:20:36 -07004925 */
Minchan Kimbc75d332009-06-16 15:32:48 -07004926void setup_per_zone_wmarks(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -07004927{
4928 unsigned long pages_min = min_free_kbytes >> (PAGE_SHIFT - 10);
4929 unsigned long lowmem_pages = 0;
4930 struct zone *zone;
4931 unsigned long flags;
4932
4933 /* Calculate total number of !ZONE_HIGHMEM pages */
4934 for_each_zone(zone) {
4935 if (!is_highmem(zone))
4936 lowmem_pages += zone->present_pages;
4937 }
4938
4939 for_each_zone(zone) {
Andrew Mortonac924c62006-05-15 09:43:59 -07004940 u64 tmp;
4941
Gerald Schaefer1125b4e2008-10-18 20:27:11 -07004942 spin_lock_irqsave(&zone->lock, flags);
Andrew Mortonac924c62006-05-15 09:43:59 -07004943 tmp = (u64)pages_min * zone->present_pages;
4944 do_div(tmp, lowmem_pages);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004945 if (is_highmem(zone)) {
4946 /*
Nick Piggin669ed172005-11-13 16:06:45 -08004947 * __GFP_HIGH and PF_MEMALLOC allocations usually don't
4948 * need highmem pages, so cap pages_min to a small
4949 * value here.
4950 *
Mel Gorman41858962009-06-16 15:32:12 -07004951 * The WMARK_HIGH-WMARK_LOW and (WMARK_LOW-WMARK_MIN)
Nick Piggin669ed172005-11-13 16:06:45 -08004952 * deltas controls asynch page reclaim, and so should
4953 * not be capped for highmem.
Linus Torvalds1da177e2005-04-16 15:20:36 -07004954 */
4955 int min_pages;
4956
4957 min_pages = zone->present_pages / 1024;
4958 if (min_pages < SWAP_CLUSTER_MAX)
4959 min_pages = SWAP_CLUSTER_MAX;
4960 if (min_pages > 128)
4961 min_pages = 128;
Mel Gorman41858962009-06-16 15:32:12 -07004962 zone->watermark[WMARK_MIN] = min_pages;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004963 } else {
Nick Piggin669ed172005-11-13 16:06:45 -08004964 /*
4965 * If it's a lowmem zone, reserve a number of pages
Linus Torvalds1da177e2005-04-16 15:20:36 -07004966 * proportionate to the zone's size.
4967 */
Mel Gorman41858962009-06-16 15:32:12 -07004968 zone->watermark[WMARK_MIN] = tmp;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004969 }
4970
Mel Gorman41858962009-06-16 15:32:12 -07004971 zone->watermark[WMARK_LOW] = min_wmark_pages(zone) + (tmp >> 2);
4972 zone->watermark[WMARK_HIGH] = min_wmark_pages(zone) + (tmp >> 1);
Mel Gorman56fd56b2007-10-16 01:25:58 -07004973 setup_zone_migrate_reserve(zone);
Gerald Schaefer1125b4e2008-10-18 20:27:11 -07004974 spin_unlock_irqrestore(&zone->lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004975 }
Hideo AOKIcb45b0e2006-04-10 22:52:59 -07004976
4977 /* update totalreserve_pages */
4978 calculate_totalreserve_pages();
Linus Torvalds1da177e2005-04-16 15:20:36 -07004979}
4980
Randy Dunlap55a44622009-09-21 17:01:20 -07004981/*
Rik van Riel556adec2008-10-18 20:26:34 -07004982 * The inactive anon list should be small enough that the VM never has to
4983 * do too much work, but large enough that each inactive page has a chance
4984 * to be referenced again before it is swapped out.
4985 *
4986 * The inactive_anon ratio is the target ratio of ACTIVE_ANON to
4987 * INACTIVE_ANON pages on this zone's LRU, maintained by the
4988 * pageout code. A zone->inactive_ratio of 3 means 3:1 or 25% of
4989 * the anonymous pages are kept on the inactive list.
4990 *
4991 * total target max
4992 * memory ratio inactive anon
4993 * -------------------------------------
4994 * 10MB 1 5MB
4995 * 100MB 1 50MB
4996 * 1GB 3 250MB
4997 * 10GB 10 0.9GB
4998 * 100GB 31 3GB
4999 * 1TB 101 10GB
5000 * 10TB 320 32GB
5001 */
Minchan Kim96cb4df2009-06-16 15:32:49 -07005002void calculate_zone_inactive_ratio(struct zone *zone)
5003{
5004 unsigned int gb, ratio;
5005
5006 /* Zone size in gigabytes */
5007 gb = zone->present_pages >> (30 - PAGE_SHIFT);
5008 if (gb)
5009 ratio = int_sqrt(10 * gb);
5010 else
5011 ratio = 1;
5012
5013 zone->inactive_ratio = ratio;
5014}
5015
Cyrill Gorcunove9bb35d2009-06-16 15:32:32 -07005016static void __init setup_per_zone_inactive_ratio(void)
Rik van Riel556adec2008-10-18 20:26:34 -07005017{
5018 struct zone *zone;
5019
Minchan Kim96cb4df2009-06-16 15:32:49 -07005020 for_each_zone(zone)
5021 calculate_zone_inactive_ratio(zone);
Rik van Riel556adec2008-10-18 20:26:34 -07005022}
5023
Linus Torvalds1da177e2005-04-16 15:20:36 -07005024/*
5025 * Initialise min_free_kbytes.
5026 *
5027 * For small machines we want it small (128k min). For large machines
5028 * we want it large (64MB max). But it is not linear, because network
5029 * bandwidth does not increase linearly with machine size. We use
5030 *
5031 * min_free_kbytes = 4 * sqrt(lowmem_kbytes), for better accuracy:
5032 * min_free_kbytes = sqrt(lowmem_kbytes * 16)
5033 *
5034 * which yields
5035 *
5036 * 16MB: 512k
5037 * 32MB: 724k
5038 * 64MB: 1024k
5039 * 128MB: 1448k
5040 * 256MB: 2048k
5041 * 512MB: 2896k
5042 * 1024MB: 4096k
5043 * 2048MB: 5792k
5044 * 4096MB: 8192k
5045 * 8192MB: 11584k
5046 * 16384MB: 16384k
5047 */
Minchan Kimbc75d332009-06-16 15:32:48 -07005048static int __init init_per_zone_wmark_min(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -07005049{
5050 unsigned long lowmem_kbytes;
5051
5052 lowmem_kbytes = nr_free_buffer_pages() * (PAGE_SIZE >> 10);
5053
5054 min_free_kbytes = int_sqrt(lowmem_kbytes * 16);
5055 if (min_free_kbytes < 128)
5056 min_free_kbytes = 128;
5057 if (min_free_kbytes > 65536)
5058 min_free_kbytes = 65536;
Minchan Kimbc75d332009-06-16 15:32:48 -07005059 setup_per_zone_wmarks();
Linus Torvalds1da177e2005-04-16 15:20:36 -07005060 setup_per_zone_lowmem_reserve();
Rik van Riel556adec2008-10-18 20:26:34 -07005061 setup_per_zone_inactive_ratio();
Linus Torvalds1da177e2005-04-16 15:20:36 -07005062 return 0;
5063}
Minchan Kimbc75d332009-06-16 15:32:48 -07005064module_init(init_per_zone_wmark_min)
Linus Torvalds1da177e2005-04-16 15:20:36 -07005065
5066/*
5067 * min_free_kbytes_sysctl_handler - just a wrapper around proc_dointvec() so
5068 * that we can call two helper functions whenever min_free_kbytes
5069 * changes.
5070 */
5071int min_free_kbytes_sysctl_handler(ctl_table *table, int write,
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07005072 void __user *buffer, size_t *length, loff_t *ppos)
Linus Torvalds1da177e2005-04-16 15:20:36 -07005073{
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07005074 proc_dointvec(table, write, buffer, length, ppos);
Mel Gorman3b1d92c2007-05-06 14:49:30 -07005075 if (write)
Minchan Kimbc75d332009-06-16 15:32:48 -07005076 setup_per_zone_wmarks();
Linus Torvalds1da177e2005-04-16 15:20:36 -07005077 return 0;
5078}
5079
Christoph Lameter96146342006-07-03 00:24:13 -07005080#ifdef CONFIG_NUMA
5081int sysctl_min_unmapped_ratio_sysctl_handler(ctl_table *table, int write,
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07005082 void __user *buffer, size_t *length, loff_t *ppos)
Christoph Lameter96146342006-07-03 00:24:13 -07005083{
5084 struct zone *zone;
5085 int rc;
5086
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07005087 rc = proc_dointvec_minmax(table, write, buffer, length, ppos);
Christoph Lameter96146342006-07-03 00:24:13 -07005088 if (rc)
5089 return rc;
5090
5091 for_each_zone(zone)
Christoph Lameter8417bba2006-09-25 23:31:51 -07005092 zone->min_unmapped_pages = (zone->present_pages *
Christoph Lameter96146342006-07-03 00:24:13 -07005093 sysctl_min_unmapped_ratio) / 100;
5094 return 0;
5095}
Christoph Lameter0ff38492006-09-25 23:31:52 -07005096
5097int sysctl_min_slab_ratio_sysctl_handler(ctl_table *table, int write,
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07005098 void __user *buffer, size_t *length, loff_t *ppos)
Christoph Lameter0ff38492006-09-25 23:31:52 -07005099{
5100 struct zone *zone;
5101 int rc;
5102
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07005103 rc = proc_dointvec_minmax(table, write, buffer, length, ppos);
Christoph Lameter0ff38492006-09-25 23:31:52 -07005104 if (rc)
5105 return rc;
5106
5107 for_each_zone(zone)
5108 zone->min_slab_pages = (zone->present_pages *
5109 sysctl_min_slab_ratio) / 100;
5110 return 0;
5111}
Christoph Lameter96146342006-07-03 00:24:13 -07005112#endif
5113
Linus Torvalds1da177e2005-04-16 15:20:36 -07005114/*
5115 * lowmem_reserve_ratio_sysctl_handler - just a wrapper around
5116 * proc_dointvec() so that we can call setup_per_zone_lowmem_reserve()
5117 * whenever sysctl_lowmem_reserve_ratio changes.
5118 *
5119 * The reserve ratio obviously has absolutely no relation with the
Mel Gorman41858962009-06-16 15:32:12 -07005120 * minimum watermarks. The lowmem reserve ratio can only make sense
Linus Torvalds1da177e2005-04-16 15:20:36 -07005121 * if in function of the boot time zone sizes.
5122 */
5123int lowmem_reserve_ratio_sysctl_handler(ctl_table *table, int write,
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07005124 void __user *buffer, size_t *length, loff_t *ppos)
Linus Torvalds1da177e2005-04-16 15:20:36 -07005125{
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07005126 proc_dointvec_minmax(table, write, buffer, length, ppos);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005127 setup_per_zone_lowmem_reserve();
5128 return 0;
5129}
5130
Rohit Seth8ad4b1f2006-01-08 01:00:40 -08005131/*
5132 * percpu_pagelist_fraction - changes the pcp->high for each zone on each
5133 * cpu. It is the fraction of total pages in each zone that a hot per cpu pagelist
5134 * can have before it gets flushed back to buddy allocator.
5135 */
5136
5137int percpu_pagelist_fraction_sysctl_handler(ctl_table *table, int write,
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07005138 void __user *buffer, size_t *length, loff_t *ppos)
Rohit Seth8ad4b1f2006-01-08 01:00:40 -08005139{
5140 struct zone *zone;
5141 unsigned int cpu;
5142 int ret;
5143
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07005144 ret = proc_dointvec_minmax(table, write, buffer, length, ppos);
Rohit Seth8ad4b1f2006-01-08 01:00:40 -08005145 if (!write || (ret == -EINVAL))
5146 return ret;
Dimitri Sivanich364df0e2009-06-23 12:37:04 -07005147 for_each_populated_zone(zone) {
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09005148 for_each_possible_cpu(cpu) {
Rohit Seth8ad4b1f2006-01-08 01:00:40 -08005149 unsigned long high;
5150 high = zone->present_pages / percpu_pagelist_fraction;
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09005151 setup_pagelist_highmark(
5152 per_cpu_ptr(zone->pageset, cpu), high);
Rohit Seth8ad4b1f2006-01-08 01:00:40 -08005153 }
5154 }
5155 return 0;
5156}
5157
David S. Millerf034b5d2006-08-24 03:08:07 -07005158int hashdist = HASHDIST_DEFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07005159
5160#ifdef CONFIG_NUMA
5161static int __init set_hashdist(char *str)
5162{
5163 if (!str)
5164 return 0;
5165 hashdist = simple_strtoul(str, &str, 0);
5166 return 1;
5167}
5168__setup("hashdist=", set_hashdist);
5169#endif
5170
5171/*
5172 * allocate a large system hash table from bootmem
5173 * - it is assumed that the hash table must contain an exact power-of-2
5174 * quantity of entries
5175 * - limit is the number of hash buckets, not the total allocation size
5176 */
5177void *__init alloc_large_system_hash(const char *tablename,
5178 unsigned long bucketsize,
5179 unsigned long numentries,
5180 int scale,
5181 int flags,
5182 unsigned int *_hash_shift,
5183 unsigned int *_hash_mask,
5184 unsigned long limit)
5185{
5186 unsigned long long max = limit;
5187 unsigned long log2qty, size;
5188 void *table = NULL;
5189
5190 /* allow the kernel cmdline to have a say */
5191 if (!numentries) {
5192 /* round applicable memory size up to nearest megabyte */
Andrew Morton04903662006-12-06 20:37:33 -08005193 numentries = nr_kernel_pages;
Linus Torvalds1da177e2005-04-16 15:20:36 -07005194 numentries += (1UL << (20 - PAGE_SHIFT)) - 1;
5195 numentries >>= 20 - PAGE_SHIFT;
5196 numentries <<= 20 - PAGE_SHIFT;
5197
5198 /* limit to 1 bucket per 2^scale bytes of low memory */
5199 if (scale > PAGE_SHIFT)
5200 numentries >>= (scale - PAGE_SHIFT);
5201 else
5202 numentries <<= (PAGE_SHIFT - scale);
Paul Mundt9ab37b82007-01-05 16:36:30 -08005203
5204 /* Make sure we've got at least a 0-order allocation.. */
Jan Beulich2c85f512009-09-21 17:03:07 -07005205 if (unlikely(flags & HASH_SMALL)) {
5206 /* Makes no sense without HASH_EARLY */
5207 WARN_ON(!(flags & HASH_EARLY));
5208 if (!(numentries >> *_hash_shift)) {
5209 numentries = 1UL << *_hash_shift;
5210 BUG_ON(!numentries);
5211 }
5212 } else if (unlikely((numentries * bucketsize) < PAGE_SIZE))
Paul Mundt9ab37b82007-01-05 16:36:30 -08005213 numentries = PAGE_SIZE / bucketsize;
Linus Torvalds1da177e2005-04-16 15:20:36 -07005214 }
John Hawkes6e692ed2006-03-25 03:08:02 -08005215 numentries = roundup_pow_of_two(numentries);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005216
5217 /* limit allocation size to 1/16 total memory by default */
5218 if (max == 0) {
5219 max = ((unsigned long long)nr_all_pages << PAGE_SHIFT) >> 4;
5220 do_div(max, bucketsize);
5221 }
5222
5223 if (numentries > max)
5224 numentries = max;
5225
David Howellsf0d1b0b2006-12-08 02:37:49 -08005226 log2qty = ilog2(numentries);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005227
5228 do {
5229 size = bucketsize << log2qty;
5230 if (flags & HASH_EARLY)
Jan Beulich74768ed2008-08-12 15:08:39 -07005231 table = alloc_bootmem_nopanic(size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07005232 else if (hashdist)
5233 table = __vmalloc(size, GFP_ATOMIC, PAGE_KERNEL);
5234 else {
Eric Dumazet1037b832007-07-15 23:38:05 -07005235 /*
5236 * If bucketsize is not a power-of-two, we may free
Mel Gormana1dd2682009-06-16 15:32:19 -07005237 * some pages at the end of hash table which
5238 * alloc_pages_exact() automatically does
Eric Dumazet1037b832007-07-15 23:38:05 -07005239 */
Catalin Marinas264ef8a2009-07-07 10:33:01 +01005240 if (get_order(size) < MAX_ORDER) {
Mel Gormana1dd2682009-06-16 15:32:19 -07005241 table = alloc_pages_exact(size, GFP_ATOMIC);
Catalin Marinas264ef8a2009-07-07 10:33:01 +01005242 kmemleak_alloc(table, size, 1, GFP_ATOMIC);
5243 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07005244 }
5245 } while (!table && size > PAGE_SIZE && --log2qty);
5246
5247 if (!table)
5248 panic("Failed to allocate %s hash table\n", tablename);
5249
Robin Holtf241e662010-10-07 12:59:26 -07005250 printk(KERN_INFO "%s hash table entries: %ld (order: %d, %lu bytes)\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -07005251 tablename,
Robin Holtf241e662010-10-07 12:59:26 -07005252 (1UL << log2qty),
David Howellsf0d1b0b2006-12-08 02:37:49 -08005253 ilog2(size) - PAGE_SHIFT,
Linus Torvalds1da177e2005-04-16 15:20:36 -07005254 size);
5255
5256 if (_hash_shift)
5257 *_hash_shift = log2qty;
5258 if (_hash_mask)
5259 *_hash_mask = (1 << log2qty) - 1;
5260
5261 return table;
5262}
KAMEZAWA Hiroyukia117e662006-03-27 01:15:25 -08005263
Mel Gorman835c1342007-10-16 01:25:47 -07005264/* Return a pointer to the bitmap storing bits affecting a block of pages */
5265static inline unsigned long *get_pageblock_bitmap(struct zone *zone,
5266 unsigned long pfn)
5267{
5268#ifdef CONFIG_SPARSEMEM
5269 return __pfn_to_section(pfn)->pageblock_flags;
5270#else
5271 return zone->pageblock_flags;
5272#endif /* CONFIG_SPARSEMEM */
5273}
Andrew Morton6220ec72006-10-19 23:29:05 -07005274
Mel Gorman835c1342007-10-16 01:25:47 -07005275static inline int pfn_to_bitidx(struct zone *zone, unsigned long pfn)
5276{
5277#ifdef CONFIG_SPARSEMEM
5278 pfn &= (PAGES_PER_SECTION-1);
Mel Gormand9c23402007-10-16 01:26:01 -07005279 return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS;
Mel Gorman835c1342007-10-16 01:25:47 -07005280#else
5281 pfn = pfn - zone->zone_start_pfn;
Mel Gormand9c23402007-10-16 01:26:01 -07005282 return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS;
Mel Gorman835c1342007-10-16 01:25:47 -07005283#endif /* CONFIG_SPARSEMEM */
5284}
5285
5286/**
Mel Gormand9c23402007-10-16 01:26:01 -07005287 * get_pageblock_flags_group - Return the requested group of flags for the pageblock_nr_pages block of pages
Mel Gorman835c1342007-10-16 01:25:47 -07005288 * @page: The page within the block of interest
5289 * @start_bitidx: The first bit of interest to retrieve
5290 * @end_bitidx: The last bit of interest
5291 * returns pageblock_bits flags
5292 */
5293unsigned long get_pageblock_flags_group(struct page *page,
5294 int start_bitidx, int end_bitidx)
5295{
5296 struct zone *zone;
5297 unsigned long *bitmap;
5298 unsigned long pfn, bitidx;
5299 unsigned long flags = 0;
5300 unsigned long value = 1;
5301
5302 zone = page_zone(page);
5303 pfn = page_to_pfn(page);
5304 bitmap = get_pageblock_bitmap(zone, pfn);
5305 bitidx = pfn_to_bitidx(zone, pfn);
5306
5307 for (; start_bitidx <= end_bitidx; start_bitidx++, value <<= 1)
5308 if (test_bit(bitidx + start_bitidx, bitmap))
5309 flags |= value;
5310
5311 return flags;
5312}
5313
5314/**
Mel Gormand9c23402007-10-16 01:26:01 -07005315 * set_pageblock_flags_group - Set the requested group of flags for a pageblock_nr_pages block of pages
Mel Gorman835c1342007-10-16 01:25:47 -07005316 * @page: The page within the block of interest
5317 * @start_bitidx: The first bit of interest
5318 * @end_bitidx: The last bit of interest
5319 * @flags: The flags to set
5320 */
5321void set_pageblock_flags_group(struct page *page, unsigned long flags,
5322 int start_bitidx, int end_bitidx)
5323{
5324 struct zone *zone;
5325 unsigned long *bitmap;
5326 unsigned long pfn, bitidx;
5327 unsigned long value = 1;
5328
5329 zone = page_zone(page);
5330 pfn = page_to_pfn(page);
5331 bitmap = get_pageblock_bitmap(zone, pfn);
5332 bitidx = pfn_to_bitidx(zone, pfn);
KAMEZAWA Hiroyuki86051ca2008-04-29 00:58:21 -07005333 VM_BUG_ON(pfn < zone->zone_start_pfn);
5334 VM_BUG_ON(pfn >= zone->zone_start_pfn + zone->spanned_pages);
Mel Gorman835c1342007-10-16 01:25:47 -07005335
5336 for (; start_bitidx <= end_bitidx; start_bitidx++, value <<= 1)
5337 if (flags & value)
5338 __set_bit(bitidx + start_bitidx, bitmap);
5339 else
5340 __clear_bit(bitidx + start_bitidx, bitmap);
5341}
KAMEZAWA Hiroyukia5d76b52007-10-16 01:26:11 -07005342
5343/*
5344 * This is designed as sub function...plz see page_isolation.c also.
5345 * set/clear page block's type to be ISOLATE.
5346 * page allocater never alloc memory from ISOLATE block.
5347 */
5348
KAMEZAWA Hiroyuki49ac8252010-10-26 14:21:30 -07005349static int
5350__count_immobile_pages(struct zone *zone, struct page *page, int count)
5351{
5352 unsigned long pfn, iter, found;
5353 /*
5354 * For avoiding noise data, lru_add_drain_all() should be called
5355 * If ZONE_MOVABLE, the zone never contains immobile pages
5356 */
5357 if (zone_idx(zone) == ZONE_MOVABLE)
5358 return true;
5359
5360 if (get_pageblock_migratetype(page) == MIGRATE_MOVABLE)
5361 return true;
5362
5363 pfn = page_to_pfn(page);
5364 for (found = 0, iter = 0; iter < pageblock_nr_pages; iter++) {
5365 unsigned long check = pfn + iter;
5366
5367 if (!pfn_valid_within(check)) {
5368 iter++;
5369 continue;
5370 }
5371 page = pfn_to_page(check);
5372 if (!page_count(page)) {
5373 if (PageBuddy(page))
5374 iter += (1 << page_order(page)) - 1;
5375 continue;
5376 }
5377 if (!PageLRU(page))
5378 found++;
5379 /*
5380 * If there are RECLAIMABLE pages, we need to check it.
5381 * But now, memory offline itself doesn't call shrink_slab()
5382 * and it still to be fixed.
5383 */
5384 /*
5385 * If the page is not RAM, page_count()should be 0.
5386 * we don't need more check. This is an _used_ not-movable page.
5387 *
5388 * The problematic thing here is PG_reserved pages. PG_reserved
5389 * is set to both of a memory hole page and a _used_ kernel
5390 * page at boot.
5391 */
5392 if (found > count)
5393 return false;
5394 }
5395 return true;
5396}
5397
5398bool is_pageblock_removable_nolock(struct page *page)
5399{
5400 struct zone *zone = page_zone(page);
5401 return __count_immobile_pages(zone, page, 0);
5402}
5403
KAMEZAWA Hiroyukia5d76b52007-10-16 01:26:11 -07005404int set_migratetype_isolate(struct page *page)
5405{
5406 struct zone *zone;
KAMEZAWA Hiroyuki49ac8252010-10-26 14:21:30 -07005407 unsigned long flags, pfn;
Robert Jennings925cc712009-12-17 14:44:38 +00005408 struct memory_isolate_notify arg;
5409 int notifier_ret;
KAMEZAWA Hiroyukia5d76b52007-10-16 01:26:11 -07005410 int ret = -EBUSY;
Shaohua Li8e7e40d2009-09-21 17:01:18 -07005411 int zone_idx;
KAMEZAWA Hiroyukia5d76b52007-10-16 01:26:11 -07005412
5413 zone = page_zone(page);
Shaohua Li8e7e40d2009-09-21 17:01:18 -07005414 zone_idx = zone_idx(zone);
Robert Jennings925cc712009-12-17 14:44:38 +00005415
KAMEZAWA Hiroyukia5d76b52007-10-16 01:26:11 -07005416 spin_lock_irqsave(&zone->lock, flags);
Robert Jennings925cc712009-12-17 14:44:38 +00005417
5418 pfn = page_to_pfn(page);
5419 arg.start_pfn = pfn;
5420 arg.nr_pages = pageblock_nr_pages;
5421 arg.pages_found = 0;
5422
5423 /*
5424 * It may be possible to isolate a pageblock even if the
5425 * migratetype is not MIGRATE_MOVABLE. The memory isolation
5426 * notifier chain is used by balloon drivers to return the
5427 * number of pages in a range that are held by the balloon
5428 * driver to shrink memory. If all the pages are accounted for
5429 * by balloons, are free, or on the LRU, isolation can continue.
5430 * Later, for example, when memory hotplug notifier runs, these
5431 * pages reported as "can be isolated" should be isolated(freed)
5432 * by the balloon driver through the memory notifier chain.
5433 */
5434 notifier_ret = memory_isolate_notify(MEM_ISOLATE_COUNT, &arg);
5435 notifier_ret = notifier_to_errno(notifier_ret);
KAMEZAWA Hiroyuki4b204772010-10-26 14:21:29 -07005436 if (notifier_ret)
Robert Jennings925cc712009-12-17 14:44:38 +00005437 goto out;
KAMEZAWA Hiroyuki49ac8252010-10-26 14:21:30 -07005438 /*
5439 * FIXME: Now, memory hotplug doesn't call shrink_slab() by itself.
5440 * We just check MOVABLE pages.
5441 */
5442 if (__count_immobile_pages(zone, page, arg.pages_found))
Robert Jennings925cc712009-12-17 14:44:38 +00005443 ret = 0;
5444
KAMEZAWA Hiroyuki49ac8252010-10-26 14:21:30 -07005445 /*
5446 * immobile means "not-on-lru" paes. If immobile is larger than
5447 * removable-by-driver pages reported by notifier, we'll fail.
5448 */
5449
KAMEZAWA Hiroyukia5d76b52007-10-16 01:26:11 -07005450out:
Robert Jennings925cc712009-12-17 14:44:38 +00005451 if (!ret) {
5452 set_pageblock_migratetype(page, MIGRATE_ISOLATE);
5453 move_freepages_block(zone, page, MIGRATE_ISOLATE);
5454 }
5455
KAMEZAWA Hiroyukia5d76b52007-10-16 01:26:11 -07005456 spin_unlock_irqrestore(&zone->lock, flags);
5457 if (!ret)
Christoph Lameter9f8f2172008-02-04 22:29:11 -08005458 drain_all_pages();
KAMEZAWA Hiroyukia5d76b52007-10-16 01:26:11 -07005459 return ret;
5460}
5461
5462void unset_migratetype_isolate(struct page *page)
5463{
5464 struct zone *zone;
5465 unsigned long flags;
5466 zone = page_zone(page);
5467 spin_lock_irqsave(&zone->lock, flags);
5468 if (get_pageblock_migratetype(page) != MIGRATE_ISOLATE)
5469 goto out;
5470 set_pageblock_migratetype(page, MIGRATE_MOVABLE);
5471 move_freepages_block(zone, page, MIGRATE_MOVABLE);
5472out:
5473 spin_unlock_irqrestore(&zone->lock, flags);
5474}
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07005475
5476#ifdef CONFIG_MEMORY_HOTREMOVE
5477/*
5478 * All pages in the range must be isolated before calling this.
5479 */
5480void
5481__offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
5482{
5483 struct page *page;
5484 struct zone *zone;
5485 int order, i;
5486 unsigned long pfn;
5487 unsigned long flags;
5488 /* find the first valid pfn */
5489 for (pfn = start_pfn; pfn < end_pfn; pfn++)
5490 if (pfn_valid(pfn))
5491 break;
5492 if (pfn == end_pfn)
5493 return;
5494 zone = page_zone(pfn_to_page(pfn));
5495 spin_lock_irqsave(&zone->lock, flags);
5496 pfn = start_pfn;
5497 while (pfn < end_pfn) {
5498 if (!pfn_valid(pfn)) {
5499 pfn++;
5500 continue;
5501 }
5502 page = pfn_to_page(pfn);
5503 BUG_ON(page_count(page));
5504 BUG_ON(!PageBuddy(page));
5505 order = page_order(page);
5506#ifdef CONFIG_DEBUG_VM
5507 printk(KERN_INFO "remove from free list %lx %d %lx\n",
5508 pfn, 1 << order, end_pfn);
5509#endif
5510 list_del(&page->lru);
5511 rmv_page_order(page);
5512 zone->free_area[order].nr_free--;
5513 __mod_zone_page_state(zone, NR_FREE_PAGES,
5514 - (1UL << order));
5515 for (i = 0; i < (1 << order); i++)
5516 SetPageReserved((page+i));
5517 pfn += (1 << order);
5518 }
5519 spin_unlock_irqrestore(&zone->lock, flags);
5520}
5521#endif
Wu Fengguang8d22ba12009-12-16 12:19:58 +01005522
5523#ifdef CONFIG_MEMORY_FAILURE
5524bool is_free_buddy_page(struct page *page)
5525{
5526 struct zone *zone = page_zone(page);
5527 unsigned long pfn = page_to_pfn(page);
5528 unsigned long flags;
5529 int order;
5530
5531 spin_lock_irqsave(&zone->lock, flags);
5532 for (order = 0; order < MAX_ORDER; order++) {
5533 struct page *page_head = page - (pfn & ((1 << order) - 1));
5534
5535 if (PageBuddy(page_head) && page_order(page_head) >= order)
5536 break;
5537 }
5538 spin_unlock_irqrestore(&zone->lock, flags);
5539
5540 return order < MAX_ORDER;
5541}
5542#endif
Wu Fengguang718a3822010-03-10 15:20:43 -08005543
5544static struct trace_print_flags pageflag_names[] = {
5545 {1UL << PG_locked, "locked" },
5546 {1UL << PG_error, "error" },
5547 {1UL << PG_referenced, "referenced" },
5548 {1UL << PG_uptodate, "uptodate" },
5549 {1UL << PG_dirty, "dirty" },
5550 {1UL << PG_lru, "lru" },
5551 {1UL << PG_active, "active" },
5552 {1UL << PG_slab, "slab" },
5553 {1UL << PG_owner_priv_1, "owner_priv_1" },
5554 {1UL << PG_arch_1, "arch_1" },
5555 {1UL << PG_reserved, "reserved" },
5556 {1UL << PG_private, "private" },
5557 {1UL << PG_private_2, "private_2" },
5558 {1UL << PG_writeback, "writeback" },
5559#ifdef CONFIG_PAGEFLAGS_EXTENDED
5560 {1UL << PG_head, "head" },
5561 {1UL << PG_tail, "tail" },
5562#else
5563 {1UL << PG_compound, "compound" },
5564#endif
5565 {1UL << PG_swapcache, "swapcache" },
5566 {1UL << PG_mappedtodisk, "mappedtodisk" },
5567 {1UL << PG_reclaim, "reclaim" },
Wu Fengguang718a3822010-03-10 15:20:43 -08005568 {1UL << PG_swapbacked, "swapbacked" },
5569 {1UL << PG_unevictable, "unevictable" },
5570#ifdef CONFIG_MMU
5571 {1UL << PG_mlocked, "mlocked" },
5572#endif
5573#ifdef CONFIG_ARCH_USES_PG_UNCACHED
5574 {1UL << PG_uncached, "uncached" },
5575#endif
5576#ifdef CONFIG_MEMORY_FAILURE
5577 {1UL << PG_hwpoison, "hwpoison" },
5578#endif
5579 {-1UL, NULL },
5580};
5581
5582static void dump_page_flags(unsigned long flags)
5583{
5584 const char *delim = "";
5585 unsigned long mask;
5586 int i;
5587
5588 printk(KERN_ALERT "page flags: %#lx(", flags);
5589
5590 /* remove zone id */
5591 flags &= (1UL << NR_PAGEFLAGS) - 1;
5592
5593 for (i = 0; pageflag_names[i].name && flags; i++) {
5594
5595 mask = pageflag_names[i].mask;
5596 if ((flags & mask) != mask)
5597 continue;
5598
5599 flags &= ~mask;
5600 printk("%s%s", delim, pageflag_names[i].name);
5601 delim = "|";
5602 }
5603
5604 /* check for left over flags */
5605 if (flags)
5606 printk("%s%#lx", delim, flags);
5607
5608 printk(")\n");
5609}
5610
5611void dump_page(struct page *page)
5612{
5613 printk(KERN_ALERT
5614 "page:%p count:%d mapcount:%d mapping:%p index:%#lx\n",
Andrea Arcangeli4e9f64c2011-01-13 15:46:29 -08005615 page, atomic_read(&page->_count), page_mapcount(page),
Wu Fengguang718a3822010-03-10 15:20:43 -08005616 page->mapping, page->index);
5617 dump_page_flags(page->flags);
5618}