blob: a8182c89de5920b5eb91809676ee884d89bbfcaf [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>
24#include <linux/compiler.h>
Randy Dunlap9f158332005-09-13 01:25:16 -070025#include <linux/kernel.h>
Vegard Nossumb1eeab62008-11-25 16:55:53 +010026#include <linux/kmemcheck.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070027#include <linux/module.h>
28#include <linux/suspend.h>
29#include <linux/pagevec.h>
30#include <linux/blkdev.h>
31#include <linux/slab.h>
David Rientjes5a3135c22007-10-16 23:25:53 -070032#include <linux/oom.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070033#include <linux/notifier.h>
34#include <linux/topology.h>
35#include <linux/sysctl.h>
36#include <linux/cpu.h>
37#include <linux/cpuset.h>
Dave Hansenbdc8cb92005-10-29 18:16:53 -070038#include <linux/memory_hotplug.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070039#include <linux/nodemask.h>
40#include <linux/vmalloc.h>
Christoph Lameter4be38e32006-01-06 00:11:17 -080041#include <linux/mempolicy.h>
Yasunori Goto68113782006-06-23 02:03:11 -070042#include <linux/stop_machine.h>
Mel Gormanc7132162006-09-27 01:49:43 -070043#include <linux/sort.h>
44#include <linux/pfn.h>
Andrew Morton3fcfab12006-10-19 23:28:16 -070045#include <linux/backing-dev.h>
Akinobu Mita933e3122006-12-08 02:39:45 -080046#include <linux/fault-inject.h>
KAMEZAWA Hiroyukia5d76b52007-10-16 01:26:11 -070047#include <linux/page-isolation.h>
KAMEZAWA Hiroyuki52d4b9a2008-10-18 20:28:16 -070048#include <linux/page_cgroup.h>
Thomas Gleixner3ac7fe52008-04-30 00:55:01 -070049#include <linux/debugobjects.h>
Catalin Marinasdbb1f812009-06-11 13:23:19 +010050#include <linux/kmemleak.h>
Robert Jennings925cc712009-12-17 14:44:38 +000051#include <linux/memory.h>
Mel Gorman0d3d0622009-09-21 17:02:44 -070052#include <trace/events/kmem.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070053
54#include <asm/tlbflush.h>
Andrew Mortonac924c62006-05-15 09:43:59 -070055#include <asm/div64.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070056#include "internal.h"
57
58/*
Christoph Lameter13808912007-10-16 01:25:27 -070059 * Array of node states.
Linus Torvalds1da177e2005-04-16 15:20:36 -070060 */
Christoph Lameter13808912007-10-16 01:25:27 -070061nodemask_t node_states[NR_NODE_STATES] __read_mostly = {
62 [N_POSSIBLE] = NODE_MASK_ALL,
63 [N_ONLINE] = { { [0] = 1UL } },
64#ifndef CONFIG_NUMA
65 [N_NORMAL_MEMORY] = { { [0] = 1UL } },
66#ifdef CONFIG_HIGHMEM
67 [N_HIGH_MEMORY] = { { [0] = 1UL } },
68#endif
69 [N_CPU] = { { [0] = 1UL } },
70#endif /* NUMA */
71};
72EXPORT_SYMBOL(node_states);
73
Ravikiran G Thirumalai6c231b72005-09-06 15:17:45 -070074unsigned long totalram_pages __read_mostly;
Hideo AOKIcb45b0e2006-04-10 22:52:59 -070075unsigned long totalreserve_pages __read_mostly;
Rohit Seth8ad4b1f2006-01-08 01:00:40 -080076int percpu_pagelist_fraction;
Benjamin Herrenschmidtdcce2842009-06-18 13:24:12 +100077gfp_t gfp_allowed_mask __read_mostly = GFP_BOOT_MASK;
Linus Torvalds1da177e2005-04-16 15:20:36 -070078
Rafael J. Wysocki452aa692010-03-05 13:42:13 -080079#ifdef CONFIG_PM_SLEEP
80/*
81 * The following functions are used by the suspend/hibernate code to temporarily
82 * change gfp_allowed_mask in order to avoid using I/O during memory allocations
83 * while devices are suspended. To avoid races with the suspend/hibernate code,
84 * they should always be called with pm_mutex held (gfp_allowed_mask also should
85 * only be modified with pm_mutex held, unless the suspend/hibernate code is
86 * guaranteed not to run in parallel with that modification).
87 */
88void set_gfp_allowed_mask(gfp_t mask)
89{
90 WARN_ON(!mutex_is_locked(&pm_mutex));
91 gfp_allowed_mask = mask;
92}
93
94gfp_t clear_gfp_allowed_mask(gfp_t mask)
95{
96 gfp_t ret = gfp_allowed_mask;
97
98 WARN_ON(!mutex_is_locked(&pm_mutex));
99 gfp_allowed_mask &= ~mask;
100 return ret;
101}
102#endif /* CONFIG_PM_SLEEP */
103
Mel Gormand9c23402007-10-16 01:26:01 -0700104#ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
105int pageblock_order __read_mostly;
106#endif
107
Hugh Dickinsd98c7a02006-02-14 13:52:59 -0800108static void __free_pages_ok(struct page *page, unsigned int order);
David Howellsa226f6c2006-01-06 00:11:08 -0800109
Linus Torvalds1da177e2005-04-16 15:20:36 -0700110/*
111 * results with 256, 32 in the lowmem_reserve sysctl:
112 * 1G machine -> (16M dma, 800M-16M normal, 1G-800M high)
113 * 1G machine -> (16M dma, 784M normal, 224M high)
114 * NORMAL allocation will leave 784M/256 of ram reserved in the ZONE_DMA
115 * HIGHMEM allocation will leave 224M/32 of ram reserved in ZONE_NORMAL
116 * HIGHMEM allocation will (224M+784M)/256 of ram reserved in ZONE_DMA
Andi Kleena2f1b422005-11-05 17:25:53 +0100117 *
118 * TBD: should special case ZONE_DMA32 machines here - in those we normally
119 * don't need any ZONE_NORMAL reservation
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120 */
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700121int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES-1] = {
Christoph Lameter4b51d662007-02-10 01:43:10 -0800122#ifdef CONFIG_ZONE_DMA
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700123 256,
Christoph Lameter4b51d662007-02-10 01:43:10 -0800124#endif
Christoph Lameterfb0e7942006-09-25 23:31:13 -0700125#ifdef CONFIG_ZONE_DMA32
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700126 256,
Christoph Lameterfb0e7942006-09-25 23:31:13 -0700127#endif
Christoph Lametere53ef382006-09-25 23:31:14 -0700128#ifdef CONFIG_HIGHMEM
Mel Gorman2a1e2742007-07-17 04:03:12 -0700129 32,
Christoph Lametere53ef382006-09-25 23:31:14 -0700130#endif
Mel Gorman2a1e2742007-07-17 04:03:12 -0700131 32,
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700132};
Linus Torvalds1da177e2005-04-16 15:20:36 -0700133
134EXPORT_SYMBOL(totalram_pages);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135
Helge Deller15ad7cd2006-12-06 20:40:36 -0800136static char * const zone_names[MAX_NR_ZONES] = {
Christoph Lameter4b51d662007-02-10 01:43:10 -0800137#ifdef CONFIG_ZONE_DMA
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700138 "DMA",
Christoph Lameter4b51d662007-02-10 01:43:10 -0800139#endif
Christoph Lameterfb0e7942006-09-25 23:31:13 -0700140#ifdef CONFIG_ZONE_DMA32
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700141 "DMA32",
Christoph Lameterfb0e7942006-09-25 23:31:13 -0700142#endif
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700143 "Normal",
Christoph Lametere53ef382006-09-25 23:31:14 -0700144#ifdef CONFIG_HIGHMEM
Mel Gorman2a1e2742007-07-17 04:03:12 -0700145 "HighMem",
Christoph Lametere53ef382006-09-25 23:31:14 -0700146#endif
Mel Gorman2a1e2742007-07-17 04:03:12 -0700147 "Movable",
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700148};
149
Linus Torvalds1da177e2005-04-16 15:20:36 -0700150int min_free_kbytes = 1024;
151
Jan Beulich2c85f512009-09-21 17:03:07 -0700152static unsigned long __meminitdata nr_kernel_pages;
153static unsigned long __meminitdata nr_all_pages;
Yasunori Gotoa3142c82007-05-08 00:23:07 -0700154static unsigned long __meminitdata dma_reserve;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700155
Mel Gormanc7132162006-09-27 01:49:43 -0700156#ifdef CONFIG_ARCH_POPULATES_NODE_MAP
157 /*
Simon Arlott183ff222007-10-20 01:27:18 +0200158 * MAX_ACTIVE_REGIONS determines the maximum number of distinct
Mel Gormanc7132162006-09-27 01:49:43 -0700159 * ranges of memory (RAM) that may be registered with add_active_range().
160 * Ranges passed to add_active_range() will be merged if possible
161 * so the number of times add_active_range() can be called is
162 * related to the number of nodes and the number of holes
163 */
164 #ifdef CONFIG_MAX_ACTIVE_REGIONS
165 /* Allow an architecture to set MAX_ACTIVE_REGIONS to save memory */
166 #define MAX_ACTIVE_REGIONS CONFIG_MAX_ACTIVE_REGIONS
167 #else
168 #if MAX_NUMNODES >= 32
169 /* If there can be many nodes, allow up to 50 holes per node */
170 #define MAX_ACTIVE_REGIONS (MAX_NUMNODES*50)
171 #else
172 /* By default, allow up to 256 distinct regions */
173 #define MAX_ACTIVE_REGIONS 256
174 #endif
175 #endif
176
Jan Beulich98011f52007-07-15 23:38:17 -0700177 static struct node_active_region __meminitdata early_node_map[MAX_ACTIVE_REGIONS];
178 static int __meminitdata nr_nodemap_entries;
179 static unsigned long __meminitdata arch_zone_lowest_possible_pfn[MAX_NR_ZONES];
180 static unsigned long __meminitdata arch_zone_highest_possible_pfn[MAX_NR_ZONES];
Adrian Bunkb69a7282008-07-23 21:28:12 -0700181 static unsigned long __initdata required_kernelcore;
Adrian Bunk484f51f2007-10-16 01:26:03 -0700182 static unsigned long __initdata required_movablecore;
Adrian Bunkb69a7282008-07-23 21:28:12 -0700183 static unsigned long __meminitdata zone_movable_pfn[MAX_NUMNODES];
Mel Gorman2a1e2742007-07-17 04:03:12 -0700184
185 /* movable_zone is the "real" zone pages in ZONE_MOVABLE are taken from */
186 int movable_zone;
187 EXPORT_SYMBOL(movable_zone);
Mel Gormanc7132162006-09-27 01:49:43 -0700188#endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
189
Miklos Szeredi418508c2007-05-23 13:57:55 -0700190#if MAX_NUMNODES > 1
191int nr_node_ids __read_mostly = MAX_NUMNODES;
Christoph Lameter62bc62a2009-06-16 15:32:15 -0700192int nr_online_nodes __read_mostly = 1;
Miklos Szeredi418508c2007-05-23 13:57:55 -0700193EXPORT_SYMBOL(nr_node_ids);
Christoph Lameter62bc62a2009-06-16 15:32:15 -0700194EXPORT_SYMBOL(nr_online_nodes);
Miklos Szeredi418508c2007-05-23 13:57:55 -0700195#endif
196
Mel Gorman9ef9acb2007-10-16 01:25:54 -0700197int page_group_by_mobility_disabled __read_mostly;
198
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700199static void set_pageblock_migratetype(struct page *page, int migratetype)
200{
Mel Gorman49255c62009-06-16 15:31:58 -0700201
202 if (unlikely(page_group_by_mobility_disabled))
203 migratetype = MIGRATE_UNMOVABLE;
204
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700205 set_pageblock_flags_group(page, (unsigned long)migratetype,
206 PB_migrate, PB_migrate_end);
207}
208
Rafael J. Wysocki7f33d492009-06-16 15:32:41 -0700209bool oom_killer_disabled __read_mostly;
210
Nick Piggin13e74442006-01-06 00:10:58 -0800211#ifdef CONFIG_DEBUG_VM
Dave Hansenc6a57e12005-10-29 18:16:52 -0700212static int page_outside_zone_boundaries(struct zone *zone, struct page *page)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700213{
Dave Hansenbdc8cb92005-10-29 18:16:53 -0700214 int ret = 0;
215 unsigned seq;
216 unsigned long pfn = page_to_pfn(page);
Dave Hansenc6a57e12005-10-29 18:16:52 -0700217
Dave Hansenbdc8cb92005-10-29 18:16:53 -0700218 do {
219 seq = zone_span_seqbegin(zone);
220 if (pfn >= zone->zone_start_pfn + zone->spanned_pages)
221 ret = 1;
222 else if (pfn < zone->zone_start_pfn)
223 ret = 1;
224 } while (zone_span_seqretry(zone, seq));
225
226 return ret;
Dave Hansenc6a57e12005-10-29 18:16:52 -0700227}
228
229static int page_is_consistent(struct zone *zone, struct page *page)
230{
Andy Whitcroft14e07292007-05-06 14:49:14 -0700231 if (!pfn_valid_within(page_to_pfn(page)))
Dave Hansenc6a57e12005-10-29 18:16:52 -0700232 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700233 if (zone != page_zone(page))
Dave Hansenc6a57e12005-10-29 18:16:52 -0700234 return 0;
235
236 return 1;
237}
238/*
239 * Temporary debugging check for pages not lying within a given zone.
240 */
241static int bad_range(struct zone *zone, struct page *page)
242{
243 if (page_outside_zone_boundaries(zone, page))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700244 return 1;
Dave Hansenc6a57e12005-10-29 18:16:52 -0700245 if (!page_is_consistent(zone, page))
246 return 1;
247
Linus Torvalds1da177e2005-04-16 15:20:36 -0700248 return 0;
249}
Nick Piggin13e74442006-01-06 00:10:58 -0800250#else
251static inline int bad_range(struct zone *zone, struct page *page)
252{
253 return 0;
254}
255#endif
256
Nick Piggin224abf92006-01-06 00:11:11 -0800257static void bad_page(struct page *page)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258{
Hugh Dickinsd936cf92009-01-06 14:40:12 -0800259 static unsigned long resume;
260 static unsigned long nr_shown;
261 static unsigned long nr_unshown;
262
Wu Fengguang2a7684a2009-09-16 11:50:12 +0200263 /* Don't complain about poisoned pages */
264 if (PageHWPoison(page)) {
265 __ClearPageBuddy(page);
266 return;
267 }
268
Hugh Dickinsd936cf92009-01-06 14:40:12 -0800269 /*
270 * Allow a burst of 60 reports, then keep quiet for that minute;
271 * or allow a steady drip of one report per second.
272 */
273 if (nr_shown == 60) {
274 if (time_before(jiffies, resume)) {
275 nr_unshown++;
276 goto out;
277 }
278 if (nr_unshown) {
Hugh Dickins1e9e6362009-01-06 14:40:13 -0800279 printk(KERN_ALERT
280 "BUG: Bad page state: %lu messages suppressed\n",
Hugh Dickinsd936cf92009-01-06 14:40:12 -0800281 nr_unshown);
282 nr_unshown = 0;
283 }
284 nr_shown = 0;
285 }
286 if (nr_shown++ == 0)
287 resume = jiffies + 60 * HZ;
288
Hugh Dickins1e9e6362009-01-06 14:40:13 -0800289 printk(KERN_ALERT "BUG: Bad page state in process %s pfn:%05lx\n",
Hugh Dickins3dc14742009-01-06 14:40:08 -0800290 current->comm, page_to_pfn(page));
Hugh Dickins1e9e6362009-01-06 14:40:13 -0800291 printk(KERN_ALERT
Hugh Dickins3dc14742009-01-06 14:40:08 -0800292 "page:%p flags:%p count:%d mapcount:%d mapping:%p index:%lx\n",
293 page, (void *)page->flags, page_count(page),
294 page_mapcount(page), page->mapping, page->index);
KAMEZAWA Hiroyuki52d4b9a2008-10-18 20:28:16 -0700295
Linus Torvalds1da177e2005-04-16 15:20:36 -0700296 dump_stack();
Hugh Dickinsd936cf92009-01-06 14:40:12 -0800297out:
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800298 /* Leave bad fields for debug, except PageBuddy could make trouble */
299 __ClearPageBuddy(page);
Randy Dunlap9f158332005-09-13 01:25:16 -0700300 add_taint(TAINT_BAD_PAGE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700301}
302
Linus Torvalds1da177e2005-04-16 15:20:36 -0700303/*
304 * Higher-order pages are called "compound pages". They are structured thusly:
305 *
306 * The first PAGE_SIZE page is called the "head page".
307 *
308 * The remaining PAGE_SIZE pages are called "tail pages".
309 *
310 * All pages have PG_compound set. All pages have their ->private pointing at
311 * the head page (even the head page has this).
312 *
Hugh Dickins41d78ba2006-02-14 13:52:58 -0800313 * The first tail page's ->lru.next holds the address of the compound page's
314 * put_page() function. Its ->lru.prev holds the order of allocation.
315 * This usage means that zero-order pages may not be compound.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700316 */
Hugh Dickinsd98c7a02006-02-14 13:52:59 -0800317
318static void free_compound_page(struct page *page)
319{
Christoph Lameterd85f3382007-05-06 14:49:39 -0700320 __free_pages_ok(page, compound_order(page));
Hugh Dickinsd98c7a02006-02-14 13:52:59 -0800321}
322
Andi Kleen01ad1c02008-07-23 21:27:46 -0700323void prep_compound_page(struct page *page, unsigned long order)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700324{
325 int i;
326 int nr_pages = 1 << order;
327
Andy Whitcroft33f2ef82006-12-06 20:33:32 -0800328 set_compound_page_dtor(page, free_compound_page);
Christoph Lameterd85f3382007-05-06 14:49:39 -0700329 set_compound_order(page, order);
Christoph Lameter6d777952007-05-06 14:49:40 -0700330 __SetPageHead(page);
Andy Whitcroft18229df2008-11-06 12:53:27 -0800331 for (i = 1; i < nr_pages; i++) {
332 struct page *p = page + i;
333
Christoph Lameterd85f3382007-05-06 14:49:39 -0700334 __SetPageTail(p);
Christoph Lameterd85f3382007-05-06 14:49:39 -0700335 p->first_page = page;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700336 }
337}
338
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800339static int destroy_compound_page(struct page *page, unsigned long order)
Andy Whitcroft18229df2008-11-06 12:53:27 -0800340{
341 int i;
342 int nr_pages = 1 << order;
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800343 int bad = 0;
Andy Whitcroft18229df2008-11-06 12:53:27 -0800344
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800345 if (unlikely(compound_order(page) != order) ||
346 unlikely(!PageHead(page))) {
Nick Piggin224abf92006-01-06 00:11:11 -0800347 bad_page(page);
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800348 bad++;
349 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700350
Christoph Lameter6d777952007-05-06 14:49:40 -0700351 __ClearPageHead(page);
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800352
Andy Whitcroft18229df2008-11-06 12:53:27 -0800353 for (i = 1; i < nr_pages; i++) {
354 struct page *p = page + i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700355
Alexey Zaytseve713a212009-01-10 02:47:57 +0300356 if (unlikely(!PageTail(p) || (p->first_page != page))) {
Nick Piggin224abf92006-01-06 00:11:11 -0800357 bad_page(page);
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800358 bad++;
359 }
Christoph Lameterd85f3382007-05-06 14:49:39 -0700360 __ClearPageTail(p);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700361 }
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800362
363 return bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700364}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700365
Nick Piggin17cf4402006-03-22 00:08:41 -0800366static inline void prep_zero_page(struct page *page, int order, gfp_t gfp_flags)
367{
368 int i;
369
Andrew Morton6626c5d2006-03-22 00:08:42 -0800370 /*
371 * clear_highpage() will use KM_USER0, so it's a bug to use __GFP_ZERO
372 * and __GFP_HIGHMEM from hard or soft interrupt context.
373 */
Nick Piggin725d7042006-09-25 23:30:55 -0700374 VM_BUG_ON((gfp_flags & __GFP_HIGHMEM) && in_interrupt());
Nick Piggin17cf4402006-03-22 00:08:41 -0800375 for (i = 0; i < (1 << order); i++)
376 clear_highpage(page + i);
377}
378
Andrew Morton6aa3001b22006-04-18 22:20:52 -0700379static inline void set_page_order(struct page *page, int order)
380{
Hugh Dickins4c21e2f2005-10-29 18:16:40 -0700381 set_page_private(page, order);
Nick Piggin676165a2006-04-10 11:21:48 +1000382 __SetPageBuddy(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700383}
384
385static inline void rmv_page_order(struct page *page)
386{
Nick Piggin676165a2006-04-10 11:21:48 +1000387 __ClearPageBuddy(page);
Hugh Dickins4c21e2f2005-10-29 18:16:40 -0700388 set_page_private(page, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700389}
390
391/*
392 * Locate the struct page for both the matching buddy in our
393 * pair (buddy1) and the combined O(n+1) page they form (page).
394 *
395 * 1) Any buddy B1 will have an order O twin B2 which satisfies
396 * the following equation:
397 * B2 = B1 ^ (1 << O)
398 * For example, if the starting buddy (buddy2) is #8 its order
399 * 1 buddy is #10:
400 * B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10
401 *
402 * 2) Any buddy B will have an order O+1 parent P which
403 * satisfies the following equation:
404 * P = B & ~(1 << O)
405 *
Andreas Mohrd6e05ed2006-06-26 18:35:02 +0200406 * Assumption: *_mem_map is contiguous at least up to MAX_ORDER
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407 */
408static inline struct page *
409__page_find_buddy(struct page *page, unsigned long page_idx, unsigned int order)
410{
411 unsigned long buddy_idx = page_idx ^ (1 << order);
412
413 return page + (buddy_idx - page_idx);
414}
415
416static inline unsigned long
417__find_combined_index(unsigned long page_idx, unsigned int order)
418{
419 return (page_idx & ~(1 << order));
420}
421
422/*
423 * This function checks whether a page is free && is the buddy
424 * we can do coalesce a page and its buddy if
Nick Piggin13e74442006-01-06 00:10:58 -0800425 * (a) the buddy is not in a hole &&
Nick Piggin676165a2006-04-10 11:21:48 +1000426 * (b) the buddy is in the buddy system &&
Andy Whitcroftcb2b95e2006-06-23 02:03:01 -0700427 * (c) a page and its buddy have the same order &&
428 * (d) a page and its buddy are in the same zone.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700429 *
Nick Piggin676165a2006-04-10 11:21:48 +1000430 * For recording whether a page is in the buddy system, we use PG_buddy.
431 * Setting, clearing, and testing PG_buddy is serialized by zone->lock.
432 *
433 * For recording page's order, we use page_private(page).
Linus Torvalds1da177e2005-04-16 15:20:36 -0700434 */
Andy Whitcroftcb2b95e2006-06-23 02:03:01 -0700435static inline int page_is_buddy(struct page *page, struct page *buddy,
436 int order)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700437{
Andy Whitcroft14e07292007-05-06 14:49:14 -0700438 if (!pfn_valid_within(page_to_pfn(buddy)))
Nick Piggin13e74442006-01-06 00:10:58 -0800439 return 0;
Nick Piggin13e74442006-01-06 00:10:58 -0800440
Andy Whitcroftcb2b95e2006-06-23 02:03:01 -0700441 if (page_zone_id(page) != page_zone_id(buddy))
442 return 0;
443
444 if (PageBuddy(buddy) && page_order(buddy) == order) {
Nick Piggina3af9c32009-06-16 15:32:10 -0700445 VM_BUG_ON(page_count(buddy) != 0);
Andrew Morton6aa3001b22006-04-18 22:20:52 -0700446 return 1;
Nick Piggin676165a2006-04-10 11:21:48 +1000447 }
Andrew Morton6aa3001b22006-04-18 22:20:52 -0700448 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700449}
450
451/*
452 * Freeing function for a buddy system allocator.
453 *
454 * The concept of a buddy system is to maintain direct-mapped table
455 * (containing bit values) for memory blocks of various "orders".
456 * The bottom level table contains the map for the smallest allocatable
457 * units of memory (here, pages), and each level above it describes
458 * pairs of units from the levels below, hence, "buddies".
459 * At a high level, all that happens here is marking the table entry
460 * at the bottom level available, and propagating the changes upward
461 * as necessary, plus some accounting needed to play nicely with other
462 * parts of the VM system.
463 * At each level, we keep a list of pages, which are heads of continuous
Nick Piggin676165a2006-04-10 11:21:48 +1000464 * free pages of length of (1 << order) and marked with PG_buddy. Page's
Hugh Dickins4c21e2f2005-10-29 18:16:40 -0700465 * order is recorded in page_private(page) field.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466 * So when we are allocating or freeing one, we can derive the state of the
467 * other. That is, if we allocate a small block, and both were
468 * free, the remainder of the region must be split into blocks.
469 * If a block is freed, and its buddy is also free, then this
470 * triggers coalescing into a block of larger size.
471 *
472 * -- wli
473 */
474
Nick Piggin48db57f2006-01-08 01:00:42 -0800475static inline void __free_one_page(struct page *page,
Mel Gormaned0ae212009-06-16 15:32:07 -0700476 struct zone *zone, unsigned int order,
477 int migratetype)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700478{
479 unsigned long page_idx;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700480
Nick Piggin224abf92006-01-06 00:11:11 -0800481 if (unlikely(PageCompound(page)))
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800482 if (unlikely(destroy_compound_page(page, order)))
483 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700484
Mel Gormaned0ae212009-06-16 15:32:07 -0700485 VM_BUG_ON(migratetype == -1);
486
Linus Torvalds1da177e2005-04-16 15:20:36 -0700487 page_idx = page_to_pfn(page) & ((1 << MAX_ORDER) - 1);
488
Mel Gormanf2260e62009-06-16 15:32:13 -0700489 VM_BUG_ON(page_idx & ((1 << order) - 1));
Nick Piggin725d7042006-09-25 23:30:55 -0700490 VM_BUG_ON(bad_range(zone, page));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700491
Linus Torvalds1da177e2005-04-16 15:20:36 -0700492 while (order < MAX_ORDER-1) {
493 unsigned long combined_idx;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700494 struct page *buddy;
495
Linus Torvalds1da177e2005-04-16 15:20:36 -0700496 buddy = __page_find_buddy(page, page_idx, order);
Andy Whitcroftcb2b95e2006-06-23 02:03:01 -0700497 if (!page_is_buddy(page, buddy, order))
Andy Whitcroft3c82d0c2008-07-23 21:27:11 -0700498 break;
Nick Piggin13e74442006-01-06 00:10:58 -0800499
Andy Whitcroft3c82d0c2008-07-23 21:27:11 -0700500 /* Our buddy is free, merge with it and move up one order. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700501 list_del(&buddy->lru);
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700502 zone->free_area[order].nr_free--;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700503 rmv_page_order(buddy);
Nick Piggin13e74442006-01-06 00:10:58 -0800504 combined_idx = __find_combined_index(page_idx, order);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700505 page = page + (combined_idx - page_idx);
506 page_idx = combined_idx;
507 order++;
508 }
509 set_page_order(page, order);
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700510 list_add(&page->lru,
511 &zone->free_area[order].free_list[migratetype]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700512 zone->free_area[order].nr_free++;
513}
514
KOSAKI Motohiro092cead2009-06-16 15:32:17 -0700515/*
516 * free_page_mlock() -- clean up attempts to free and mlocked() page.
517 * Page should not be on lru, so no need to fix that up.
518 * free_pages_check() will verify...
519 */
520static inline void free_page_mlock(struct page *page)
521{
KOSAKI Motohiro092cead2009-06-16 15:32:17 -0700522 __dec_zone_page_state(page, NR_MLOCK);
523 __count_vm_event(UNEVICTABLE_MLOCKFREED);
524}
KOSAKI Motohiro092cead2009-06-16 15:32:17 -0700525
Nick Piggin224abf92006-01-06 00:11:11 -0800526static inline int free_pages_check(struct page *page)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700527{
Nick Piggin92be2e332006-01-06 00:10:57 -0800528 if (unlikely(page_mapcount(page) |
529 (page->mapping != NULL) |
Nick Piggina3af9c32009-06-16 15:32:10 -0700530 (atomic_read(&page->_count) != 0) |
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800531 (page->flags & PAGE_FLAGS_CHECK_AT_FREE))) {
Nick Piggin224abf92006-01-06 00:11:11 -0800532 bad_page(page);
Hugh Dickins79f4b7b2009-01-06 14:40:05 -0800533 return 1;
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800534 }
Hugh Dickins79f4b7b2009-01-06 14:40:05 -0800535 if (page->flags & PAGE_FLAGS_CHECK_AT_PREP)
536 page->flags &= ~PAGE_FLAGS_CHECK_AT_PREP;
537 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700538}
539
540/*
Mel Gorman5f8dcc22009-09-21 17:03:19 -0700541 * Frees a number of pages from the PCP lists
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542 * Assumes all pages on list are in same zone, and of same order.
Renaud Lienhart207f36e2005-09-10 00:26:59 -0700543 * count is the number of pages to free.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700544 *
545 * If the zone was previously in an "all pages pinned" state then look to
546 * see if this freeing clears that state.
547 *
548 * And clear the zone's pages_scanned counter, to hold off the "all pages are
549 * pinned" detection logic.
550 */
Mel Gorman5f8dcc22009-09-21 17:03:19 -0700551static void free_pcppages_bulk(struct zone *zone, int count,
552 struct per_cpu_pages *pcp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700553{
Mel Gorman5f8dcc22009-09-21 17:03:19 -0700554 int migratetype = 0;
Mel Gormana6f9edd2009-09-21 17:03:20 -0700555 int batch_free = 0;
Mel Gorman5f8dcc22009-09-21 17:03:19 -0700556
Nick Pigginc54ad302006-01-06 00:10:56 -0800557 spin_lock(&zone->lock);
KOSAKI Motohiro93e4a892010-03-05 13:41:55 -0800558 zone->all_unreclaimable = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700559 zone->pages_scanned = 0;
Mel Gormanf2260e62009-06-16 15:32:13 -0700560
Mel Gorman5f8dcc22009-09-21 17:03:19 -0700561 __mod_zone_page_state(zone, NR_FREE_PAGES, count);
Mel Gormana6f9edd2009-09-21 17:03:20 -0700562 while (count) {
Nick Piggin48db57f2006-01-08 01:00:42 -0800563 struct page *page;
Mel Gorman5f8dcc22009-09-21 17:03:19 -0700564 struct list_head *list;
Nick Piggin48db57f2006-01-08 01:00:42 -0800565
Mel Gorman5f8dcc22009-09-21 17:03:19 -0700566 /*
Mel Gormana6f9edd2009-09-21 17:03:20 -0700567 * Remove pages from lists in a round-robin fashion. A
568 * batch_free count is maintained that is incremented when an
569 * empty list is encountered. This is so more pages are freed
570 * off fuller lists instead of spinning excessively around empty
571 * lists
Mel Gorman5f8dcc22009-09-21 17:03:19 -0700572 */
573 do {
Mel Gormana6f9edd2009-09-21 17:03:20 -0700574 batch_free++;
Mel Gorman5f8dcc22009-09-21 17:03:19 -0700575 if (++migratetype == MIGRATE_PCPTYPES)
576 migratetype = 0;
577 list = &pcp->lists[migratetype];
578 } while (list_empty(list));
579
Mel Gormana6f9edd2009-09-21 17:03:20 -0700580 do {
581 page = list_entry(list->prev, struct page, lru);
582 /* must delete as __free_one_page list manipulates */
583 list_del(&page->lru);
Hugh Dickinsa7016232010-01-29 17:46:34 +0000584 /* MIGRATE_MOVABLE list may include MIGRATE_RESERVEs */
585 __free_one_page(page, zone, 0, page_private(page));
586 trace_mm_page_pcpu_drain(page, 0, page_private(page));
Mel Gormana6f9edd2009-09-21 17:03:20 -0700587 } while (--count && --batch_free && !list_empty(list));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700588 }
Nick Pigginc54ad302006-01-06 00:10:56 -0800589 spin_unlock(&zone->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700590}
591
Mel Gormaned0ae212009-06-16 15:32:07 -0700592static void free_one_page(struct zone *zone, struct page *page, int order,
593 int migratetype)
Nick Piggin48db57f2006-01-08 01:00:42 -0800594{
Christoph Lameter006d22d2006-09-25 23:31:48 -0700595 spin_lock(&zone->lock);
KOSAKI Motohiro93e4a892010-03-05 13:41:55 -0800596 zone->all_unreclaimable = 0;
Christoph Lameter006d22d2006-09-25 23:31:48 -0700597 zone->pages_scanned = 0;
Mel Gormanf2260e62009-06-16 15:32:13 -0700598
599 __mod_zone_page_state(zone, NR_FREE_PAGES, 1 << order);
Mel Gormaned0ae212009-06-16 15:32:07 -0700600 __free_one_page(page, zone, order, migratetype);
Christoph Lameter006d22d2006-09-25 23:31:48 -0700601 spin_unlock(&zone->lock);
Nick Piggin48db57f2006-01-08 01:00:42 -0800602}
603
604static void __free_pages_ok(struct page *page, unsigned int order)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700605{
Nick Pigginc54ad302006-01-06 00:10:56 -0800606 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700607 int i;
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800608 int bad = 0;
Johannes Weiner451ea252009-09-21 17:01:48 -0700609 int wasMlocked = __TestClearPageMlocked(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700610
Li Hongf6503162010-03-05 13:41:52 -0800611 trace_mm_page_free_direct(page, order);
Vegard Nossumb1eeab62008-11-25 16:55:53 +0100612 kmemcheck_free_shadow(page, order);
613
Linus Torvalds1da177e2005-04-16 15:20:36 -0700614 for (i = 0 ; i < (1 << order) ; ++i)
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800615 bad += free_pages_check(page + i);
616 if (bad)
Hugh Dickins689bceb2005-11-21 21:32:20 -0800617 return;
618
Thomas Gleixner3ac7fe52008-04-30 00:55:01 -0700619 if (!PageHighMem(page)) {
Nick Piggin9858db52006-10-11 01:21:30 -0700620 debug_check_no_locks_freed(page_address(page),PAGE_SIZE<<order);
Thomas Gleixner3ac7fe52008-04-30 00:55:01 -0700621 debug_check_no_obj_freed(page_address(page),
622 PAGE_SIZE << order);
623 }
Nick Piggindafb1362006-10-11 01:21:30 -0700624 arch_free_page(page, order);
Nick Piggin48db57f2006-01-08 01:00:42 -0800625 kernel_map_pages(page, 1 << order, 0);
Nick Piggindafb1362006-10-11 01:21:30 -0700626
Nick Pigginc54ad302006-01-06 00:10:56 -0800627 local_irq_save(flags);
Johannes Weinerc2773312009-06-19 19:30:56 +0200628 if (unlikely(wasMlocked))
Mel Gormanda456f12009-06-16 15:32:08 -0700629 free_page_mlock(page);
Christoph Lameterf8891e52006-06-30 01:55:45 -0700630 __count_vm_events(PGFREE, 1 << order);
Mel Gormaned0ae212009-06-16 15:32:07 -0700631 free_one_page(page_zone(page), page, order,
632 get_pageblock_migratetype(page));
Nick Pigginc54ad302006-01-06 00:10:56 -0800633 local_irq_restore(flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700634}
635
David Howellsa226f6c2006-01-06 00:11:08 -0800636/*
637 * permit the bootmem allocator to evade page validation on high-order frees
638 */
Yasunori Gotoaf370fb2008-07-23 21:28:17 -0700639void __meminit __free_pages_bootmem(struct page *page, unsigned int order)
David Howellsa226f6c2006-01-06 00:11:08 -0800640{
641 if (order == 0) {
642 __ClearPageReserved(page);
643 set_page_count(page, 0);
Nick Piggin7835e982006-03-22 00:08:40 -0800644 set_page_refcounted(page);
Nick Piggin545b1ea2006-03-22 00:08:07 -0800645 __free_page(page);
David Howellsa226f6c2006-01-06 00:11:08 -0800646 } else {
David Howellsa226f6c2006-01-06 00:11:08 -0800647 int loop;
648
Nick Piggin545b1ea2006-03-22 00:08:07 -0800649 prefetchw(page);
David Howellsa226f6c2006-01-06 00:11:08 -0800650 for (loop = 0; loop < BITS_PER_LONG; loop++) {
651 struct page *p = &page[loop];
652
Nick Piggin545b1ea2006-03-22 00:08:07 -0800653 if (loop + 1 < BITS_PER_LONG)
654 prefetchw(p + 1);
David Howellsa226f6c2006-01-06 00:11:08 -0800655 __ClearPageReserved(p);
656 set_page_count(p, 0);
657 }
658
Nick Piggin7835e982006-03-22 00:08:40 -0800659 set_page_refcounted(page);
Nick Piggin545b1ea2006-03-22 00:08:07 -0800660 __free_pages(page, order);
David Howellsa226f6c2006-01-06 00:11:08 -0800661 }
662}
663
Linus Torvalds1da177e2005-04-16 15:20:36 -0700664
665/*
666 * The order of subdivision here is critical for the IO subsystem.
667 * Please do not alter this order without good reasons and regression
668 * testing. Specifically, as large blocks of memory are subdivided,
669 * the order in which smaller blocks are delivered depends on the order
670 * they're subdivided in this function. This is the primary factor
671 * influencing the order in which pages are delivered to the IO
672 * subsystem according to empirical testing, and this is also justified
673 * by considering the behavior of a buddy system containing a single
674 * large block of memory acted on by a series of small allocations.
675 * This behavior is a critical factor in sglist merging's success.
676 *
677 * -- wli
678 */
Nick Piggin085cc7d2006-01-06 00:11:01 -0800679static inline void expand(struct zone *zone, struct page *page,
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700680 int low, int high, struct free_area *area,
681 int migratetype)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700682{
683 unsigned long size = 1 << high;
684
685 while (high > low) {
686 area--;
687 high--;
688 size >>= 1;
Nick Piggin725d7042006-09-25 23:30:55 -0700689 VM_BUG_ON(bad_range(zone, &page[size]));
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700690 list_add(&page[size].lru, &area->free_list[migratetype]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700691 area->nr_free++;
692 set_page_order(&page[size], high);
693 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700694}
695
Linus Torvalds1da177e2005-04-16 15:20:36 -0700696/*
697 * This page is about to be returned from the page allocator
698 */
Wu Fengguang2a7684a2009-09-16 11:50:12 +0200699static inline int check_new_page(struct page *page)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700700{
Nick Piggin92be2e332006-01-06 00:10:57 -0800701 if (unlikely(page_mapcount(page) |
702 (page->mapping != NULL) |
Nick Piggina3af9c32009-06-16 15:32:10 -0700703 (atomic_read(&page->_count) != 0) |
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800704 (page->flags & PAGE_FLAGS_CHECK_AT_PREP))) {
Nick Piggin224abf92006-01-06 00:11:11 -0800705 bad_page(page);
Hugh Dickins689bceb2005-11-21 21:32:20 -0800706 return 1;
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800707 }
Wu Fengguang2a7684a2009-09-16 11:50:12 +0200708 return 0;
709}
710
711static int prep_new_page(struct page *page, int order, gfp_t gfp_flags)
712{
713 int i;
714
715 for (i = 0; i < (1 << order); i++) {
716 struct page *p = page + i;
717 if (unlikely(check_new_page(p)))
718 return 1;
719 }
Hugh Dickins689bceb2005-11-21 21:32:20 -0800720
Hugh Dickins4c21e2f2005-10-29 18:16:40 -0700721 set_page_private(page, 0);
Nick Piggin7835e982006-03-22 00:08:40 -0800722 set_page_refcounted(page);
Nick Piggincc1025092006-12-06 20:32:00 -0800723
724 arch_alloc_page(page, order);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700725 kernel_map_pages(page, 1 << order, 1);
Nick Piggin17cf4402006-03-22 00:08:41 -0800726
727 if (gfp_flags & __GFP_ZERO)
728 prep_zero_page(page, order, gfp_flags);
729
730 if (order && (gfp_flags & __GFP_COMP))
731 prep_compound_page(page, order);
732
Hugh Dickins689bceb2005-11-21 21:32:20 -0800733 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700734}
735
Mel Gorman56fd56b2007-10-16 01:25:58 -0700736/*
737 * Go through the free lists for the given migratetype and remove
738 * the smallest available page from the freelists
739 */
Mel Gorman728ec982009-06-16 15:32:04 -0700740static inline
741struct page *__rmqueue_smallest(struct zone *zone, unsigned int order,
Mel Gorman56fd56b2007-10-16 01:25:58 -0700742 int migratetype)
743{
744 unsigned int current_order;
745 struct free_area * area;
746 struct page *page;
747
748 /* Find a page of the appropriate size in the preferred list */
749 for (current_order = order; current_order < MAX_ORDER; ++current_order) {
750 area = &(zone->free_area[current_order]);
751 if (list_empty(&area->free_list[migratetype]))
752 continue;
753
754 page = list_entry(area->free_list[migratetype].next,
755 struct page, lru);
756 list_del(&page->lru);
757 rmv_page_order(page);
758 area->nr_free--;
Mel Gorman56fd56b2007-10-16 01:25:58 -0700759 expand(zone, page, order, current_order, area, migratetype);
760 return page;
761 }
762
763 return NULL;
764}
765
766
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700767/*
768 * This array describes the order lists are fallen back to when
769 * the free lists for the desirable migrate type are depleted
770 */
771static int fallbacks[MIGRATE_TYPES][MIGRATE_TYPES-1] = {
Mel Gorman64c5e132007-10-16 01:25:59 -0700772 [MIGRATE_UNMOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_MOVABLE, MIGRATE_RESERVE },
773 [MIGRATE_RECLAIMABLE] = { MIGRATE_UNMOVABLE, MIGRATE_MOVABLE, MIGRATE_RESERVE },
774 [MIGRATE_MOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE, MIGRATE_RESERVE },
775 [MIGRATE_RESERVE] = { MIGRATE_RESERVE, MIGRATE_RESERVE, MIGRATE_RESERVE }, /* Never used */
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700776};
777
Mel Gormanc361be52007-10-16 01:25:51 -0700778/*
779 * Move the free pages in a range to the free lists of the requested type.
Mel Gormand9c23402007-10-16 01:26:01 -0700780 * Note that start_page and end_pages are not aligned on a pageblock
Mel Gormanc361be52007-10-16 01:25:51 -0700781 * boundary. If alignment is required, use move_freepages_block()
782 */
Adrian Bunkb69a7282008-07-23 21:28:12 -0700783static int move_freepages(struct zone *zone,
784 struct page *start_page, struct page *end_page,
785 int migratetype)
Mel Gormanc361be52007-10-16 01:25:51 -0700786{
787 struct page *page;
788 unsigned long order;
Mel Gormand1003132007-10-16 01:26:00 -0700789 int pages_moved = 0;
Mel Gormanc361be52007-10-16 01:25:51 -0700790
791#ifndef CONFIG_HOLES_IN_ZONE
792 /*
793 * page_zone is not safe to call in this context when
794 * CONFIG_HOLES_IN_ZONE is set. This bug check is probably redundant
795 * anyway as we check zone boundaries in move_freepages_block().
796 * Remove at a later date when no bug reports exist related to
Mel Gormanac0e5b72007-10-16 01:25:58 -0700797 * grouping pages by mobility
Mel Gormanc361be52007-10-16 01:25:51 -0700798 */
799 BUG_ON(page_zone(start_page) != page_zone(end_page));
800#endif
801
802 for (page = start_page; page <= end_page;) {
Adam Litke344c7902008-09-02 14:35:38 -0700803 /* Make sure we are not inadvertently changing nodes */
804 VM_BUG_ON(page_to_nid(page) != zone_to_nid(zone));
805
Mel Gormanc361be52007-10-16 01:25:51 -0700806 if (!pfn_valid_within(page_to_pfn(page))) {
807 page++;
808 continue;
809 }
810
811 if (!PageBuddy(page)) {
812 page++;
813 continue;
814 }
815
816 order = page_order(page);
817 list_del(&page->lru);
818 list_add(&page->lru,
819 &zone->free_area[order].free_list[migratetype]);
820 page += 1 << order;
Mel Gormand1003132007-10-16 01:26:00 -0700821 pages_moved += 1 << order;
Mel Gormanc361be52007-10-16 01:25:51 -0700822 }
823
Mel Gormand1003132007-10-16 01:26:00 -0700824 return pages_moved;
Mel Gormanc361be52007-10-16 01:25:51 -0700825}
826
Adrian Bunkb69a7282008-07-23 21:28:12 -0700827static int move_freepages_block(struct zone *zone, struct page *page,
828 int migratetype)
Mel Gormanc361be52007-10-16 01:25:51 -0700829{
830 unsigned long start_pfn, end_pfn;
831 struct page *start_page, *end_page;
832
833 start_pfn = page_to_pfn(page);
Mel Gormand9c23402007-10-16 01:26:01 -0700834 start_pfn = start_pfn & ~(pageblock_nr_pages-1);
Mel Gormanc361be52007-10-16 01:25:51 -0700835 start_page = pfn_to_page(start_pfn);
Mel Gormand9c23402007-10-16 01:26:01 -0700836 end_page = start_page + pageblock_nr_pages - 1;
837 end_pfn = start_pfn + pageblock_nr_pages - 1;
Mel Gormanc361be52007-10-16 01:25:51 -0700838
839 /* Do not cross zone boundaries */
840 if (start_pfn < zone->zone_start_pfn)
841 start_page = page;
842 if (end_pfn >= zone->zone_start_pfn + zone->spanned_pages)
843 return 0;
844
845 return move_freepages(zone, start_page, end_page, migratetype);
846}
847
Mel Gorman2f66a682009-09-21 17:02:31 -0700848static void change_pageblock_range(struct page *pageblock_page,
849 int start_order, int migratetype)
850{
851 int nr_pageblocks = 1 << (start_order - pageblock_order);
852
853 while (nr_pageblocks--) {
854 set_pageblock_migratetype(pageblock_page, migratetype);
855 pageblock_page += pageblock_nr_pages;
856 }
857}
858
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700859/* Remove an element from the buddy allocator from the fallback list */
Mel Gorman0ac3a402009-06-16 15:32:06 -0700860static inline struct page *
861__rmqueue_fallback(struct zone *zone, int order, int start_migratetype)
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700862{
863 struct free_area * area;
864 int current_order;
865 struct page *page;
866 int migratetype, i;
867
868 /* Find the largest possible block of pages in the other list */
869 for (current_order = MAX_ORDER-1; current_order >= order;
870 --current_order) {
871 for (i = 0; i < MIGRATE_TYPES - 1; i++) {
872 migratetype = fallbacks[start_migratetype][i];
873
Mel Gorman56fd56b2007-10-16 01:25:58 -0700874 /* MIGRATE_RESERVE handled later if necessary */
875 if (migratetype == MIGRATE_RESERVE)
876 continue;
Mel Gormane0104872007-10-16 01:25:53 -0700877
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700878 area = &(zone->free_area[current_order]);
879 if (list_empty(&area->free_list[migratetype]))
880 continue;
881
882 page = list_entry(area->free_list[migratetype].next,
883 struct page, lru);
884 area->nr_free--;
885
886 /*
Mel Gormanc361be52007-10-16 01:25:51 -0700887 * If breaking a large block of pages, move all free
Mel Gorman46dafbc2007-10-16 01:25:55 -0700888 * pages to the preferred allocation list. If falling
889 * back for a reclaimable kernel allocation, be more
890 * agressive about taking ownership of free pages
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700891 */
Mel Gormand9c23402007-10-16 01:26:01 -0700892 if (unlikely(current_order >= (pageblock_order >> 1)) ||
Mel Gormandd5d2412009-09-05 11:17:11 -0700893 start_migratetype == MIGRATE_RECLAIMABLE ||
894 page_group_by_mobility_disabled) {
Mel Gorman46dafbc2007-10-16 01:25:55 -0700895 unsigned long pages;
896 pages = move_freepages_block(zone, page,
897 start_migratetype);
898
899 /* Claim the whole block if over half of it is free */
Mel Gormandd5d2412009-09-05 11:17:11 -0700900 if (pages >= (1 << (pageblock_order-1)) ||
901 page_group_by_mobility_disabled)
Mel Gorman46dafbc2007-10-16 01:25:55 -0700902 set_pageblock_migratetype(page,
903 start_migratetype);
904
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700905 migratetype = start_migratetype;
Mel Gormanc361be52007-10-16 01:25:51 -0700906 }
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700907
908 /* Remove the page from the freelists */
909 list_del(&page->lru);
910 rmv_page_order(page);
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700911
Mel Gorman2f66a682009-09-21 17:02:31 -0700912 /* Take ownership for orders >= pageblock_order */
913 if (current_order >= pageblock_order)
914 change_pageblock_range(page, current_order,
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700915 start_migratetype);
916
917 expand(zone, page, order, current_order, area, migratetype);
Mel Gormane0fff1b2009-09-21 17:02:42 -0700918
919 trace_mm_page_alloc_extfrag(page, order, current_order,
920 start_migratetype, migratetype);
921
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700922 return page;
923 }
924 }
925
Mel Gorman728ec982009-06-16 15:32:04 -0700926 return NULL;
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700927}
928
Mel Gorman56fd56b2007-10-16 01:25:58 -0700929/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700930 * Do the hard work of removing an element from the buddy allocator.
931 * Call me with the zone->lock already held.
932 */
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700933static struct page *__rmqueue(struct zone *zone, unsigned int order,
934 int migratetype)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700935{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700936 struct page *page;
937
Mel Gorman728ec982009-06-16 15:32:04 -0700938retry_reserve:
Mel Gorman56fd56b2007-10-16 01:25:58 -0700939 page = __rmqueue_smallest(zone, order, migratetype);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700940
Mel Gorman728ec982009-06-16 15:32:04 -0700941 if (unlikely(!page) && migratetype != MIGRATE_RESERVE) {
Mel Gorman56fd56b2007-10-16 01:25:58 -0700942 page = __rmqueue_fallback(zone, order, migratetype);
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700943
Mel Gorman728ec982009-06-16 15:32:04 -0700944 /*
945 * Use MIGRATE_RESERVE rather than fail an allocation. goto
946 * is used because __rmqueue_smallest is an inline function
947 * and we want just one call site
948 */
949 if (!page) {
950 migratetype = MIGRATE_RESERVE;
951 goto retry_reserve;
952 }
953 }
954
Mel Gorman0d3d0622009-09-21 17:02:44 -0700955 trace_mm_page_alloc_zone_locked(page, order, migratetype);
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700956 return page;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700957}
958
959/*
960 * Obtain a specified number of elements from the buddy allocator, all under
961 * a single hold of the lock, for efficiency. Add them to the supplied list.
962 * Returns the number of new pages which were placed at *list.
963 */
964static int rmqueue_bulk(struct zone *zone, unsigned int order,
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700965 unsigned long count, struct list_head *list,
Mel Gormane084b2d2009-07-29 15:02:04 -0700966 int migratetype, int cold)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700967{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700968 int i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700969
Nick Pigginc54ad302006-01-06 00:10:56 -0800970 spin_lock(&zone->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700971 for (i = 0; i < count; ++i) {
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700972 struct page *page = __rmqueue(zone, order, migratetype);
Nick Piggin085cc7d2006-01-06 00:11:01 -0800973 if (unlikely(page == NULL))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700974 break;
Mel Gorman81eabcb2007-12-17 16:20:05 -0800975
976 /*
977 * Split buddy pages returned by expand() are received here
978 * in physical page order. The page is added to the callers and
979 * list and the list head then moves forward. From the callers
980 * perspective, the linked list is ordered by page number in
981 * some conditions. This is useful for IO devices that can
982 * merge IO requests if the physical pages are ordered
983 * properly.
984 */
Mel Gormane084b2d2009-07-29 15:02:04 -0700985 if (likely(cold == 0))
986 list_add(&page->lru, list);
987 else
988 list_add_tail(&page->lru, list);
Mel Gorman535131e62007-10-16 01:25:49 -0700989 set_page_private(page, migratetype);
Mel Gorman81eabcb2007-12-17 16:20:05 -0800990 list = &page->lru;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700991 }
Mel Gormanf2260e62009-06-16 15:32:13 -0700992 __mod_zone_page_state(zone, NR_FREE_PAGES, -(i << order));
Nick Pigginc54ad302006-01-06 00:10:56 -0800993 spin_unlock(&zone->lock);
Nick Piggin085cc7d2006-01-06 00:11:01 -0800994 return i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700995}
996
Christoph Lameter4ae7c032005-06-21 17:14:57 -0700997#ifdef CONFIG_NUMA
Christoph Lameter8fce4d82006-03-09 17:33:54 -0800998/*
Christoph Lameter4037d452007-05-09 02:35:14 -0700999 * Called from the vmstat counter updater to drain pagesets of this
1000 * currently executing processor on remote nodes after they have
1001 * expired.
1002 *
Christoph Lameter879336c2006-03-22 00:09:08 -08001003 * Note that this function must be called with the thread pinned to
1004 * a single processor.
Christoph Lameter8fce4d82006-03-09 17:33:54 -08001005 */
Christoph Lameter4037d452007-05-09 02:35:14 -07001006void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp)
Christoph Lameter4ae7c032005-06-21 17:14:57 -07001007{
Christoph Lameter4ae7c032005-06-21 17:14:57 -07001008 unsigned long flags;
Christoph Lameter4037d452007-05-09 02:35:14 -07001009 int to_drain;
Christoph Lameter4ae7c032005-06-21 17:14:57 -07001010
Christoph Lameter4037d452007-05-09 02:35:14 -07001011 local_irq_save(flags);
1012 if (pcp->count >= pcp->batch)
1013 to_drain = pcp->batch;
1014 else
1015 to_drain = pcp->count;
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001016 free_pcppages_bulk(zone, to_drain, pcp);
Christoph Lameter4037d452007-05-09 02:35:14 -07001017 pcp->count -= to_drain;
1018 local_irq_restore(flags);
Christoph Lameter4ae7c032005-06-21 17:14:57 -07001019}
1020#endif
1021
Christoph Lameter9f8f2172008-02-04 22:29:11 -08001022/*
1023 * Drain pages of the indicated processor.
1024 *
1025 * The processor must either be the current processor and the
1026 * thread pinned to the current processor or a processor that
1027 * is not online.
1028 */
1029static void drain_pages(unsigned int cpu)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001030{
Nick Pigginc54ad302006-01-06 00:10:56 -08001031 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001032 struct zone *zone;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001033
KOSAKI Motohiroee99c712009-03-31 15:19:31 -07001034 for_each_populated_zone(zone) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001035 struct per_cpu_pageset *pset;
Christoph Lameter3dfa5722008-02-04 22:29:19 -08001036 struct per_cpu_pages *pcp;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001037
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09001038 local_irq_save(flags);
1039 pset = per_cpu_ptr(zone->pageset, cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001040
Christoph Lameter3dfa5722008-02-04 22:29:19 -08001041 pcp = &pset->pcp;
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001042 free_pcppages_bulk(zone, pcp->count, pcp);
Christoph Lameter3dfa5722008-02-04 22:29:19 -08001043 pcp->count = 0;
1044 local_irq_restore(flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001045 }
1046}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001047
Christoph Lameter9f8f2172008-02-04 22:29:11 -08001048/*
1049 * Spill all of this CPU's per-cpu pages back into the buddy allocator.
1050 */
1051void drain_local_pages(void *arg)
1052{
1053 drain_pages(smp_processor_id());
1054}
1055
1056/*
1057 * Spill all the per-cpu pages from all CPUs back into the buddy allocator
1058 */
1059void drain_all_pages(void)
1060{
Jens Axboe15c8b6c2008-05-09 09:39:44 +02001061 on_each_cpu(drain_local_pages, NULL, 1);
Christoph Lameter9f8f2172008-02-04 22:29:11 -08001062}
1063
Rafael J. Wysocki296699d2007-07-29 23:27:18 +02001064#ifdef CONFIG_HIBERNATION
Linus Torvalds1da177e2005-04-16 15:20:36 -07001065
1066void mark_free_pages(struct zone *zone)
1067{
Rafael J. Wysockif623f0d2006-09-25 23:32:49 -07001068 unsigned long pfn, max_zone_pfn;
1069 unsigned long flags;
Mel Gormanb2a0ac82007-10-16 01:25:48 -07001070 int order, t;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001071 struct list_head *curr;
1072
1073 if (!zone->spanned_pages)
1074 return;
1075
1076 spin_lock_irqsave(&zone->lock, flags);
Rafael J. Wysockif623f0d2006-09-25 23:32:49 -07001077
1078 max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
1079 for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
1080 if (pfn_valid(pfn)) {
1081 struct page *page = pfn_to_page(pfn);
1082
Rafael J. Wysocki7be98232007-05-06 14:50:42 -07001083 if (!swsusp_page_is_forbidden(page))
1084 swsusp_unset_page_free(page);
Rafael J. Wysockif623f0d2006-09-25 23:32:49 -07001085 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001086
Mel Gormanb2a0ac82007-10-16 01:25:48 -07001087 for_each_migratetype_order(order, t) {
1088 list_for_each(curr, &zone->free_area[order].free_list[t]) {
Rafael J. Wysockif623f0d2006-09-25 23:32:49 -07001089 unsigned long i;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001090
Rafael J. Wysockif623f0d2006-09-25 23:32:49 -07001091 pfn = page_to_pfn(list_entry(curr, struct page, lru));
1092 for (i = 0; i < (1UL << order); i++)
Rafael J. Wysocki7be98232007-05-06 14:50:42 -07001093 swsusp_set_page_free(pfn_to_page(pfn + i));
Rafael J. Wysockif623f0d2006-09-25 23:32:49 -07001094 }
Mel Gormanb2a0ac82007-10-16 01:25:48 -07001095 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001096 spin_unlock_irqrestore(&zone->lock, flags);
1097}
Mel Gormane2c55dc2007-10-16 01:25:50 -07001098#endif /* CONFIG_PM */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001099
1100/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07001101 * Free a 0-order page
Li Hongfc916682010-03-05 13:41:54 -08001102 * cold == 1 ? free a cold page : free a hot page
Linus Torvalds1da177e2005-04-16 15:20:36 -07001103 */
Li Hongfc916682010-03-05 13:41:54 -08001104void free_hot_cold_page(struct page *page, int cold)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001105{
1106 struct zone *zone = page_zone(page);
1107 struct per_cpu_pages *pcp;
1108 unsigned long flags;
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001109 int migratetype;
Johannes Weiner451ea252009-09-21 17:01:48 -07001110 int wasMlocked = __TestClearPageMlocked(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001111
Li Hongc475dab2010-03-05 13:41:53 -08001112 trace_mm_page_free_direct(page, 0);
Vegard Nossumb1eeab62008-11-25 16:55:53 +01001113 kmemcheck_free_shadow(page, 0);
1114
Linus Torvalds1da177e2005-04-16 15:20:36 -07001115 if (PageAnon(page))
1116 page->mapping = NULL;
Nick Piggin224abf92006-01-06 00:11:11 -08001117 if (free_pages_check(page))
Hugh Dickins689bceb2005-11-21 21:32:20 -08001118 return;
1119
Thomas Gleixner3ac7fe52008-04-30 00:55:01 -07001120 if (!PageHighMem(page)) {
Nick Piggin9858db52006-10-11 01:21:30 -07001121 debug_check_no_locks_freed(page_address(page), PAGE_SIZE);
Thomas Gleixner3ac7fe52008-04-30 00:55:01 -07001122 debug_check_no_obj_freed(page_address(page), PAGE_SIZE);
1123 }
Nick Piggindafb1362006-10-11 01:21:30 -07001124 arch_free_page(page, 0);
Hugh Dickins689bceb2005-11-21 21:32:20 -08001125 kernel_map_pages(page, 1, 0);
1126
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001127 migratetype = get_pageblock_migratetype(page);
1128 set_page_private(page, migratetype);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001129 local_irq_save(flags);
Johannes Weinerc2773312009-06-19 19:30:56 +02001130 if (unlikely(wasMlocked))
Mel Gormanda456f12009-06-16 15:32:08 -07001131 free_page_mlock(page);
Christoph Lameterf8891e52006-06-30 01:55:45 -07001132 __count_vm_event(PGFREE);
Mel Gormanda456f12009-06-16 15:32:08 -07001133
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001134 /*
1135 * We only track unmovable, reclaimable and movable on pcp lists.
1136 * Free ISOLATE pages back to the allocator because they are being
1137 * offlined but treat RESERVE as movable pages so we can get those
1138 * areas back if necessary. Otherwise, we may have to free
1139 * excessively into the page allocator
1140 */
1141 if (migratetype >= MIGRATE_PCPTYPES) {
1142 if (unlikely(migratetype == MIGRATE_ISOLATE)) {
1143 free_one_page(zone, page, 0, migratetype);
1144 goto out;
1145 }
1146 migratetype = MIGRATE_MOVABLE;
1147 }
1148
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09001149 pcp = &this_cpu_ptr(zone->pageset)->pcp;
Christoph Lameter3dfa5722008-02-04 22:29:19 -08001150 if (cold)
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001151 list_add_tail(&page->lru, &pcp->lists[migratetype]);
Christoph Lameter3dfa5722008-02-04 22:29:19 -08001152 else
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001153 list_add(&page->lru, &pcp->lists[migratetype]);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001154 pcp->count++;
Nick Piggin48db57f2006-01-08 01:00:42 -08001155 if (pcp->count >= pcp->high) {
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001156 free_pcppages_bulk(zone, pcp->batch, pcp);
Nick Piggin48db57f2006-01-08 01:00:42 -08001157 pcp->count -= pcp->batch;
1158 }
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001159
1160out:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001161 local_irq_restore(flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001162}
1163
Nick Piggin8dfcc9b2006-03-22 00:08:05 -08001164/*
1165 * split_page takes a non-compound higher-order page, and splits it into
1166 * n (1<<order) sub-pages: page[0..n]
1167 * Each sub-page must be freed individually.
1168 *
1169 * Note: this is probably too low level an operation for use in drivers.
1170 * Please consult with lkml before using this in your driver.
1171 */
1172void split_page(struct page *page, unsigned int order)
1173{
1174 int i;
1175
Nick Piggin725d7042006-09-25 23:30:55 -07001176 VM_BUG_ON(PageCompound(page));
1177 VM_BUG_ON(!page_count(page));
Vegard Nossumb1eeab62008-11-25 16:55:53 +01001178
1179#ifdef CONFIG_KMEMCHECK
1180 /*
1181 * Split shadow pages too, because free(page[0]) would
1182 * otherwise free the whole shadow.
1183 */
1184 if (kmemcheck_page_is_tracked(page))
1185 split_page(virt_to_page(page[0].shadow), order);
1186#endif
1187
Nick Piggin7835e982006-03-22 00:08:40 -08001188 for (i = 1; i < (1 << order); i++)
1189 set_page_refcounted(page + i);
Nick Piggin8dfcc9b2006-03-22 00:08:05 -08001190}
Nick Piggin8dfcc9b2006-03-22 00:08:05 -08001191
Linus Torvalds1da177e2005-04-16 15:20:36 -07001192/*
1193 * Really, prep_compound_page() should be called from __rmqueue_bulk(). But
1194 * we cheat by calling it from here, in the order > 0 path. Saves a branch
1195 * or two.
1196 */
Mel Gorman0a15c3e2009-06-16 15:32:05 -07001197static inline
1198struct page *buffered_rmqueue(struct zone *preferred_zone,
Mel Gorman3dd28262009-06-16 15:32:00 -07001199 struct zone *zone, int order, gfp_t gfp_flags,
1200 int migratetype)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001201{
1202 unsigned long flags;
Hugh Dickins689bceb2005-11-21 21:32:20 -08001203 struct page *page;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001204 int cold = !!(gfp_flags & __GFP_COLD);
1205
Hugh Dickins689bceb2005-11-21 21:32:20 -08001206again:
Nick Piggin48db57f2006-01-08 01:00:42 -08001207 if (likely(order == 0)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001208 struct per_cpu_pages *pcp;
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001209 struct list_head *list;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001210
Linus Torvalds1da177e2005-04-16 15:20:36 -07001211 local_irq_save(flags);
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09001212 pcp = &this_cpu_ptr(zone->pageset)->pcp;
1213 list = &pcp->lists[migratetype];
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001214 if (list_empty(list)) {
Mel Gorman535131e62007-10-16 01:25:49 -07001215 pcp->count += rmqueue_bulk(zone, 0,
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001216 pcp->batch, list,
Mel Gormane084b2d2009-07-29 15:02:04 -07001217 migratetype, cold);
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001218 if (unlikely(list_empty(list)))
Shaohua Li6fb332f2009-09-21 17:01:17 -07001219 goto failed;
Mel Gorman535131e62007-10-16 01:25:49 -07001220 }
Mel Gormanb92a6ed2007-10-16 01:25:50 -07001221
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001222 if (cold)
1223 page = list_entry(list->prev, struct page, lru);
1224 else
1225 page = list_entry(list->next, struct page, lru);
1226
Mel Gormanb92a6ed2007-10-16 01:25:50 -07001227 list_del(&page->lru);
1228 pcp->count--;
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001229 } else {
Andrew Mortondab48da2009-06-16 15:32:37 -07001230 if (unlikely(gfp_flags & __GFP_NOFAIL)) {
1231 /*
1232 * __GFP_NOFAIL is not to be used in new code.
1233 *
1234 * All __GFP_NOFAIL callers should be fixed so that they
1235 * properly detect and handle allocation failures.
1236 *
1237 * We most definitely don't want callers attempting to
Linus Torvalds4923abf2009-06-24 12:16:49 -07001238 * allocate greater than order-1 page units with
Andrew Mortondab48da2009-06-16 15:32:37 -07001239 * __GFP_NOFAIL.
1240 */
Linus Torvalds4923abf2009-06-24 12:16:49 -07001241 WARN_ON_ONCE(order > 1);
Andrew Mortondab48da2009-06-16 15:32:37 -07001242 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001243 spin_lock_irqsave(&zone->lock, flags);
Mel Gormanb2a0ac82007-10-16 01:25:48 -07001244 page = __rmqueue(zone, order, migratetype);
Nick Piggina74609f2006-01-06 00:11:20 -08001245 spin_unlock(&zone->lock);
1246 if (!page)
1247 goto failed;
KOSAKI Motohiro6ccf80e2010-01-15 17:01:18 -08001248 __mod_zone_page_state(zone, NR_FREE_PAGES, -(1 << order));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001249 }
1250
Christoph Lameterf8891e52006-06-30 01:55:45 -07001251 __count_zone_vm_events(PGALLOC, zone, 1 << order);
Mel Gorman18ea7e72008-04-28 02:12:14 -07001252 zone_statistics(preferred_zone, zone);
Nick Piggina74609f2006-01-06 00:11:20 -08001253 local_irq_restore(flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001254
Nick Piggin725d7042006-09-25 23:30:55 -07001255 VM_BUG_ON(bad_range(zone, page));
Nick Piggin17cf4402006-03-22 00:08:41 -08001256 if (prep_new_page(page, order, gfp_flags))
Nick Piggina74609f2006-01-06 00:11:20 -08001257 goto again;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001258 return page;
Nick Piggina74609f2006-01-06 00:11:20 -08001259
1260failed:
1261 local_irq_restore(flags);
Nick Piggina74609f2006-01-06 00:11:20 -08001262 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001263}
1264
Mel Gorman41858962009-06-16 15:32:12 -07001265/* The ALLOC_WMARK bits are used as an index to zone->watermark */
1266#define ALLOC_WMARK_MIN WMARK_MIN
1267#define ALLOC_WMARK_LOW WMARK_LOW
1268#define ALLOC_WMARK_HIGH WMARK_HIGH
1269#define ALLOC_NO_WATERMARKS 0x04 /* don't check watermarks at all */
1270
1271/* Mask to get the watermark bits */
1272#define ALLOC_WMARK_MASK (ALLOC_NO_WATERMARKS-1)
1273
Nick Piggin31488902005-11-28 13:44:03 -08001274#define ALLOC_HARDER 0x10 /* try to alloc harder */
1275#define ALLOC_HIGH 0x20 /* __GFP_HIGH set */
1276#define ALLOC_CPUSET 0x40 /* check for correct cpuset */
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001277
Akinobu Mita933e3122006-12-08 02:39:45 -08001278#ifdef CONFIG_FAIL_PAGE_ALLOC
1279
1280static struct fail_page_alloc_attr {
1281 struct fault_attr attr;
1282
1283 u32 ignore_gfp_highmem;
1284 u32 ignore_gfp_wait;
Akinobu Mita54114992007-07-15 23:40:23 -07001285 u32 min_order;
Akinobu Mita933e3122006-12-08 02:39:45 -08001286
1287#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
1288
1289 struct dentry *ignore_gfp_highmem_file;
1290 struct dentry *ignore_gfp_wait_file;
Akinobu Mita54114992007-07-15 23:40:23 -07001291 struct dentry *min_order_file;
Akinobu Mita933e3122006-12-08 02:39:45 -08001292
1293#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
1294
1295} fail_page_alloc = {
1296 .attr = FAULT_ATTR_INITIALIZER,
Don Mullis6b1b60f2006-12-08 02:39:53 -08001297 .ignore_gfp_wait = 1,
1298 .ignore_gfp_highmem = 1,
Akinobu Mita54114992007-07-15 23:40:23 -07001299 .min_order = 1,
Akinobu Mita933e3122006-12-08 02:39:45 -08001300};
1301
1302static int __init setup_fail_page_alloc(char *str)
1303{
1304 return setup_fault_attr(&fail_page_alloc.attr, str);
1305}
1306__setup("fail_page_alloc=", setup_fail_page_alloc);
1307
1308static int should_fail_alloc_page(gfp_t gfp_mask, unsigned int order)
1309{
Akinobu Mita54114992007-07-15 23:40:23 -07001310 if (order < fail_page_alloc.min_order)
1311 return 0;
Akinobu Mita933e3122006-12-08 02:39:45 -08001312 if (gfp_mask & __GFP_NOFAIL)
1313 return 0;
1314 if (fail_page_alloc.ignore_gfp_highmem && (gfp_mask & __GFP_HIGHMEM))
1315 return 0;
1316 if (fail_page_alloc.ignore_gfp_wait && (gfp_mask & __GFP_WAIT))
1317 return 0;
1318
1319 return should_fail(&fail_page_alloc.attr, 1 << order);
1320}
1321
1322#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
1323
1324static int __init fail_page_alloc_debugfs(void)
1325{
1326 mode_t mode = S_IFREG | S_IRUSR | S_IWUSR;
1327 struct dentry *dir;
1328 int err;
1329
1330 err = init_fault_attr_dentries(&fail_page_alloc.attr,
1331 "fail_page_alloc");
1332 if (err)
1333 return err;
1334 dir = fail_page_alloc.attr.dentries.dir;
1335
1336 fail_page_alloc.ignore_gfp_wait_file =
1337 debugfs_create_bool("ignore-gfp-wait", mode, dir,
1338 &fail_page_alloc.ignore_gfp_wait);
1339
1340 fail_page_alloc.ignore_gfp_highmem_file =
1341 debugfs_create_bool("ignore-gfp-highmem", mode, dir,
1342 &fail_page_alloc.ignore_gfp_highmem);
Akinobu Mita54114992007-07-15 23:40:23 -07001343 fail_page_alloc.min_order_file =
1344 debugfs_create_u32("min-order", mode, dir,
1345 &fail_page_alloc.min_order);
Akinobu Mita933e3122006-12-08 02:39:45 -08001346
1347 if (!fail_page_alloc.ignore_gfp_wait_file ||
Akinobu Mita54114992007-07-15 23:40:23 -07001348 !fail_page_alloc.ignore_gfp_highmem_file ||
1349 !fail_page_alloc.min_order_file) {
Akinobu Mita933e3122006-12-08 02:39:45 -08001350 err = -ENOMEM;
1351 debugfs_remove(fail_page_alloc.ignore_gfp_wait_file);
1352 debugfs_remove(fail_page_alloc.ignore_gfp_highmem_file);
Akinobu Mita54114992007-07-15 23:40:23 -07001353 debugfs_remove(fail_page_alloc.min_order_file);
Akinobu Mita933e3122006-12-08 02:39:45 -08001354 cleanup_fault_attr_dentries(&fail_page_alloc.attr);
1355 }
1356
1357 return err;
1358}
1359
1360late_initcall(fail_page_alloc_debugfs);
1361
1362#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
1363
1364#else /* CONFIG_FAIL_PAGE_ALLOC */
1365
1366static inline int should_fail_alloc_page(gfp_t gfp_mask, unsigned int order)
1367{
1368 return 0;
1369}
1370
1371#endif /* CONFIG_FAIL_PAGE_ALLOC */
1372
Linus Torvalds1da177e2005-04-16 15:20:36 -07001373/*
1374 * Return 1 if free pages are above 'mark'. This takes into account the order
1375 * of the allocation.
1376 */
1377int zone_watermark_ok(struct zone *z, int order, unsigned long mark,
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001378 int classzone_idx, int alloc_flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001379{
1380 /* free_pages my go negative - that's OK */
Christoph Lameterd23ad422007-02-10 01:43:02 -08001381 long min = mark;
1382 long free_pages = zone_page_state(z, NR_FREE_PAGES) - (1 << order) + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001383 int o;
1384
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001385 if (alloc_flags & ALLOC_HIGH)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001386 min -= min / 2;
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001387 if (alloc_flags & ALLOC_HARDER)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001388 min -= min / 4;
1389
1390 if (free_pages <= min + z->lowmem_reserve[classzone_idx])
1391 return 0;
1392 for (o = 0; o < order; o++) {
1393 /* At the next order, this order's pages become unavailable */
1394 free_pages -= z->free_area[o].nr_free << o;
1395
1396 /* Require fewer higher order pages to be free */
1397 min >>= 1;
1398
1399 if (free_pages <= min)
1400 return 0;
1401 }
1402 return 1;
1403}
1404
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001405#ifdef CONFIG_NUMA
1406/*
1407 * zlc_setup - Setup for "zonelist cache". Uses cached zone data to
1408 * skip over zones that are not allowed by the cpuset, or that have
1409 * been recently (in last second) found to be nearly full. See further
1410 * comments in mmzone.h. Reduces cache footprint of zonelist scans
Simon Arlott183ff222007-10-20 01:27:18 +02001411 * that have to skip over a lot of full or unallowed zones.
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001412 *
1413 * If the zonelist cache is present in the passed in zonelist, then
1414 * returns a pointer to the allowed node mask (either the current
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07001415 * tasks mems_allowed, or node_states[N_HIGH_MEMORY].)
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001416 *
1417 * If the zonelist cache is not available for this zonelist, does
1418 * nothing and returns NULL.
1419 *
1420 * If the fullzones BITMAP in the zonelist cache is stale (more than
1421 * a second since last zap'd) then we zap it out (clear its bits.)
1422 *
1423 * We hold off even calling zlc_setup, until after we've checked the
1424 * first zone in the zonelist, on the theory that most allocations will
1425 * be satisfied from that first zone, so best to examine that zone as
1426 * quickly as we can.
1427 */
1428static nodemask_t *zlc_setup(struct zonelist *zonelist, int alloc_flags)
1429{
1430 struct zonelist_cache *zlc; /* cached zonelist speedup info */
1431 nodemask_t *allowednodes; /* zonelist_cache approximation */
1432
1433 zlc = zonelist->zlcache_ptr;
1434 if (!zlc)
1435 return NULL;
1436
S.Caglar Onurf05111f2008-04-28 02:12:38 -07001437 if (time_after(jiffies, zlc->last_full_zap + HZ)) {
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001438 bitmap_zero(zlc->fullzones, MAX_ZONES_PER_ZONELIST);
1439 zlc->last_full_zap = jiffies;
1440 }
1441
1442 allowednodes = !in_interrupt() && (alloc_flags & ALLOC_CPUSET) ?
1443 &cpuset_current_mems_allowed :
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07001444 &node_states[N_HIGH_MEMORY];
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001445 return allowednodes;
1446}
1447
1448/*
1449 * Given 'z' scanning a zonelist, run a couple of quick checks to see
1450 * if it is worth looking at further for free memory:
1451 * 1) Check that the zone isn't thought to be full (doesn't have its
1452 * bit set in the zonelist_cache fullzones BITMAP).
1453 * 2) Check that the zones node (obtained from the zonelist_cache
1454 * z_to_n[] mapping) is allowed in the passed in allowednodes mask.
1455 * Return true (non-zero) if zone is worth looking at further, or
1456 * else return false (zero) if it is not.
1457 *
1458 * This check -ignores- the distinction between various watermarks,
1459 * such as GFP_HIGH, GFP_ATOMIC, PF_MEMALLOC, ... If a zone is
1460 * found to be full for any variation of these watermarks, it will
1461 * be considered full for up to one second by all requests, unless
1462 * we are so low on memory on all allowed nodes that we are forced
1463 * into the second scan of the zonelist.
1464 *
1465 * In the second scan we ignore this zonelist cache and exactly
1466 * apply the watermarks to all zones, even it is slower to do so.
1467 * We are low on memory in the second scan, and should leave no stone
1468 * unturned looking for a free page.
1469 */
Mel Gormandd1a2392008-04-28 02:12:17 -07001470static int zlc_zone_worth_trying(struct zonelist *zonelist, struct zoneref *z,
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001471 nodemask_t *allowednodes)
1472{
1473 struct zonelist_cache *zlc; /* cached zonelist speedup info */
1474 int i; /* index of *z in zonelist zones */
1475 int n; /* node that zone *z is on */
1476
1477 zlc = zonelist->zlcache_ptr;
1478 if (!zlc)
1479 return 1;
1480
Mel Gormandd1a2392008-04-28 02:12:17 -07001481 i = z - zonelist->_zonerefs;
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001482 n = zlc->z_to_n[i];
1483
1484 /* This zone is worth trying if it is allowed but not full */
1485 return node_isset(n, *allowednodes) && !test_bit(i, zlc->fullzones);
1486}
1487
1488/*
1489 * Given 'z' scanning a zonelist, set the corresponding bit in
1490 * zlc->fullzones, so that subsequent attempts to allocate a page
1491 * from that zone don't waste time re-examining it.
1492 */
Mel Gormandd1a2392008-04-28 02:12:17 -07001493static void zlc_mark_zone_full(struct zonelist *zonelist, struct zoneref *z)
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001494{
1495 struct zonelist_cache *zlc; /* cached zonelist speedup info */
1496 int i; /* index of *z in zonelist zones */
1497
1498 zlc = zonelist->zlcache_ptr;
1499 if (!zlc)
1500 return;
1501
Mel Gormandd1a2392008-04-28 02:12:17 -07001502 i = z - zonelist->_zonerefs;
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001503
1504 set_bit(i, zlc->fullzones);
1505}
1506
1507#else /* CONFIG_NUMA */
1508
1509static nodemask_t *zlc_setup(struct zonelist *zonelist, int alloc_flags)
1510{
1511 return NULL;
1512}
1513
Mel Gormandd1a2392008-04-28 02:12:17 -07001514static int zlc_zone_worth_trying(struct zonelist *zonelist, struct zoneref *z,
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001515 nodemask_t *allowednodes)
1516{
1517 return 1;
1518}
1519
Mel Gormandd1a2392008-04-28 02:12:17 -07001520static void zlc_mark_zone_full(struct zonelist *zonelist, struct zoneref *z)
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001521{
1522}
1523#endif /* CONFIG_NUMA */
1524
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001525/*
Paul Jackson0798e512006-12-06 20:31:38 -08001526 * get_page_from_freelist goes through the zonelist trying to allocate
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001527 * a page.
1528 */
1529static struct page *
Mel Gorman19770b32008-04-28 02:12:18 -07001530get_page_from_freelist(gfp_t gfp_mask, nodemask_t *nodemask, unsigned int order,
Mel Gorman5117f452009-06-16 15:31:59 -07001531 struct zonelist *zonelist, int high_zoneidx, int alloc_flags,
Mel Gorman3dd28262009-06-16 15:32:00 -07001532 struct zone *preferred_zone, int migratetype)
Martin Hicks753ee722005-06-21 17:14:41 -07001533{
Mel Gormandd1a2392008-04-28 02:12:17 -07001534 struct zoneref *z;
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001535 struct page *page = NULL;
Mel Gorman54a6eb52008-04-28 02:12:16 -07001536 int classzone_idx;
Mel Gorman5117f452009-06-16 15:31:59 -07001537 struct zone *zone;
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001538 nodemask_t *allowednodes = NULL;/* zonelist_cache approximation */
1539 int zlc_active = 0; /* set if using zonelist_cache */
1540 int did_zlc_setup = 0; /* just call zlc_setup() one time */
Mel Gorman54a6eb52008-04-28 02:12:16 -07001541
Mel Gorman19770b32008-04-28 02:12:18 -07001542 classzone_idx = zone_idx(preferred_zone);
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001543zonelist_scan:
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001544 /*
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001545 * Scan zonelist, looking for a zone with enough free.
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001546 * See also cpuset_zone_allowed() comment in kernel/cpuset.c.
1547 */
Mel Gorman19770b32008-04-28 02:12:18 -07001548 for_each_zone_zonelist_nodemask(zone, z, zonelist,
1549 high_zoneidx, nodemask) {
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001550 if (NUMA_BUILD && zlc_active &&
1551 !zlc_zone_worth_trying(zonelist, z, allowednodes))
1552 continue;
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001553 if ((alloc_flags & ALLOC_CPUSET) &&
Paul Jackson02a0e532006-12-13 00:34:25 -08001554 !cpuset_zone_allowed_softwall(zone, gfp_mask))
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001555 goto try_next_zone;
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001556
Mel Gorman41858962009-06-16 15:32:12 -07001557 BUILD_BUG_ON(ALLOC_NO_WATERMARKS < NR_WMARK);
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001558 if (!(alloc_flags & ALLOC_NO_WATERMARKS)) {
Nick Piggin31488902005-11-28 13:44:03 -08001559 unsigned long mark;
Mel Gormanfa5e0842009-06-16 15:33:22 -07001560 int ret;
1561
Mel Gorman41858962009-06-16 15:32:12 -07001562 mark = zone->watermark[alloc_flags & ALLOC_WMARK_MASK];
Mel Gormanfa5e0842009-06-16 15:33:22 -07001563 if (zone_watermark_ok(zone, order, mark,
1564 classzone_idx, alloc_flags))
1565 goto try_this_zone;
1566
1567 if (zone_reclaim_mode == 0)
1568 goto this_zone_full;
1569
1570 ret = zone_reclaim(zone, gfp_mask, order);
1571 switch (ret) {
1572 case ZONE_RECLAIM_NOSCAN:
1573 /* did not scan */
1574 goto try_next_zone;
1575 case ZONE_RECLAIM_FULL:
1576 /* scanned but unreclaimable */
1577 goto this_zone_full;
1578 default:
1579 /* did we reclaim enough */
1580 if (!zone_watermark_ok(zone, order, mark,
1581 classzone_idx, alloc_flags))
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001582 goto this_zone_full;
Paul Jackson0798e512006-12-06 20:31:38 -08001583 }
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001584 }
1585
Mel Gormanfa5e0842009-06-16 15:33:22 -07001586try_this_zone:
Mel Gorman3dd28262009-06-16 15:32:00 -07001587 page = buffered_rmqueue(preferred_zone, zone, order,
1588 gfp_mask, migratetype);
Paul Jackson0798e512006-12-06 20:31:38 -08001589 if (page)
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001590 break;
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001591this_zone_full:
1592 if (NUMA_BUILD)
1593 zlc_mark_zone_full(zonelist, z);
1594try_next_zone:
Christoph Lameter62bc62a2009-06-16 15:32:15 -07001595 if (NUMA_BUILD && !did_zlc_setup && nr_online_nodes > 1) {
Mel Gormand395b732009-06-16 15:32:09 -07001596 /*
1597 * we do zlc_setup after the first zone is tried but only
1598 * if there are multiple nodes make it worthwhile
1599 */
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001600 allowednodes = zlc_setup(zonelist, alloc_flags);
1601 zlc_active = 1;
1602 did_zlc_setup = 1;
1603 }
Mel Gorman54a6eb52008-04-28 02:12:16 -07001604 }
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001605
1606 if (unlikely(NUMA_BUILD && page == NULL && zlc_active)) {
1607 /* Disable zlc cache for second zonelist scan */
1608 zlc_active = 0;
1609 goto zonelist_scan;
1610 }
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001611 return page;
Martin Hicks753ee722005-06-21 17:14:41 -07001612}
1613
Mel Gorman11e33f62009-06-16 15:31:57 -07001614static inline int
1615should_alloc_retry(gfp_t gfp_mask, unsigned int order,
1616 unsigned long pages_reclaimed)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001617{
Mel Gorman11e33f62009-06-16 15:31:57 -07001618 /* Do not loop if specifically requested */
1619 if (gfp_mask & __GFP_NORETRY)
1620 return 0;
1621
1622 /*
1623 * In this implementation, order <= PAGE_ALLOC_COSTLY_ORDER
1624 * means __GFP_NOFAIL, but that may not be true in other
1625 * implementations.
1626 */
1627 if (order <= PAGE_ALLOC_COSTLY_ORDER)
1628 return 1;
1629
1630 /*
1631 * For order > PAGE_ALLOC_COSTLY_ORDER, if __GFP_REPEAT is
1632 * specified, then we retry until we no longer reclaim any pages
1633 * (above), or we've reclaimed an order of pages at least as
1634 * large as the allocation's order. In both cases, if the
1635 * allocation still fails, we stop retrying.
1636 */
1637 if (gfp_mask & __GFP_REPEAT && pages_reclaimed < (1 << order))
1638 return 1;
1639
1640 /*
1641 * Don't let big-order allocations loop unless the caller
1642 * explicitly requests that.
1643 */
1644 if (gfp_mask & __GFP_NOFAIL)
1645 return 1;
1646
1647 return 0;
1648}
1649
1650static inline struct page *
1651__alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order,
1652 struct zonelist *zonelist, enum zone_type high_zoneidx,
Mel Gorman3dd28262009-06-16 15:32:00 -07001653 nodemask_t *nodemask, struct zone *preferred_zone,
1654 int migratetype)
Mel Gorman11e33f62009-06-16 15:31:57 -07001655{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001656 struct page *page;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001657
Mel Gorman11e33f62009-06-16 15:31:57 -07001658 /* Acquire the OOM killer lock for the zones in zonelist */
1659 if (!try_set_zone_oom(zonelist, gfp_mask)) {
1660 schedule_timeout_uninterruptible(1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001661 return NULL;
1662 }
Jens Axboe6b1de912005-11-17 21:35:02 +01001663
Mel Gorman11e33f62009-06-16 15:31:57 -07001664 /*
1665 * Go through the zonelist yet one more time, keep very high watermark
1666 * here, this is only to catch a parallel oom killing, we must fail if
1667 * we're still under heavy pressure.
1668 */
1669 page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask,
1670 order, zonelist, high_zoneidx,
Mel Gorman5117f452009-06-16 15:31:59 -07001671 ALLOC_WMARK_HIGH|ALLOC_CPUSET,
Mel Gorman3dd28262009-06-16 15:32:00 -07001672 preferred_zone, migratetype);
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001673 if (page)
Mel Gorman11e33f62009-06-16 15:31:57 -07001674 goto out;
1675
KAMEZAWA Hiroyuki4365a562009-12-15 16:45:33 -08001676 if (!(gfp_mask & __GFP_NOFAIL)) {
1677 /* The OOM killer will not help higher order allocs */
1678 if (order > PAGE_ALLOC_COSTLY_ORDER)
1679 goto out;
1680 /*
1681 * GFP_THISNODE contains __GFP_NORETRY and we never hit this.
1682 * Sanity check for bare calls of __GFP_THISNODE, not real OOM.
1683 * The caller should handle page allocation failure by itself if
1684 * it specifies __GFP_THISNODE.
1685 * Note: Hugepage uses it but will hit PAGE_ALLOC_COSTLY_ORDER.
1686 */
1687 if (gfp_mask & __GFP_THISNODE)
1688 goto out;
1689 }
Mel Gorman11e33f62009-06-16 15:31:57 -07001690 /* Exhausted what can be done so it's blamo time */
KAMEZAWA Hiroyuki4365a562009-12-15 16:45:33 -08001691 out_of_memory(zonelist, gfp_mask, order, nodemask);
Mel Gorman11e33f62009-06-16 15:31:57 -07001692
1693out:
1694 clear_zonelist_oom(zonelist, gfp_mask);
1695 return page;
1696}
1697
1698/* The really slow allocator path where we enter direct reclaim */
1699static inline struct page *
1700__alloc_pages_direct_reclaim(gfp_t gfp_mask, unsigned int order,
1701 struct zonelist *zonelist, enum zone_type high_zoneidx,
Mel Gorman5117f452009-06-16 15:31:59 -07001702 nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone,
Mel Gorman3dd28262009-06-16 15:32:00 -07001703 int migratetype, unsigned long *did_some_progress)
Mel Gorman11e33f62009-06-16 15:31:57 -07001704{
1705 struct page *page = NULL;
1706 struct reclaim_state reclaim_state;
1707 struct task_struct *p = current;
1708
1709 cond_resched();
1710
1711 /* We now go into synchronous reclaim */
1712 cpuset_memory_pressure_bump();
Mel Gorman11e33f62009-06-16 15:31:57 -07001713 p->flags |= PF_MEMALLOC;
1714 lockdep_set_current_reclaim_state(gfp_mask);
1715 reclaim_state.reclaimed_slab = 0;
1716 p->reclaim_state = &reclaim_state;
1717
1718 *did_some_progress = try_to_free_pages(zonelist, order, gfp_mask, nodemask);
1719
1720 p->reclaim_state = NULL;
1721 lockdep_clear_current_reclaim_state();
1722 p->flags &= ~PF_MEMALLOC;
1723
1724 cond_resched();
1725
1726 if (order != 0)
1727 drain_all_pages();
1728
1729 if (likely(*did_some_progress))
1730 page = get_page_from_freelist(gfp_mask, nodemask, order,
Mel Gorman5117f452009-06-16 15:31:59 -07001731 zonelist, high_zoneidx,
Mel Gorman3dd28262009-06-16 15:32:00 -07001732 alloc_flags, preferred_zone,
1733 migratetype);
Mel Gorman11e33f62009-06-16 15:31:57 -07001734 return page;
1735}
1736
Mel Gorman11e33f62009-06-16 15:31:57 -07001737/*
1738 * This is called in the allocator slow-path if the allocation request is of
1739 * sufficient urgency to ignore watermarks and take other desperate measures
1740 */
1741static inline struct page *
1742__alloc_pages_high_priority(gfp_t gfp_mask, unsigned int order,
1743 struct zonelist *zonelist, enum zone_type high_zoneidx,
Mel Gorman3dd28262009-06-16 15:32:00 -07001744 nodemask_t *nodemask, struct zone *preferred_zone,
1745 int migratetype)
Mel Gorman11e33f62009-06-16 15:31:57 -07001746{
1747 struct page *page;
1748
1749 do {
1750 page = get_page_from_freelist(gfp_mask, nodemask, order,
Mel Gorman5117f452009-06-16 15:31:59 -07001751 zonelist, high_zoneidx, ALLOC_NO_WATERMARKS,
Mel Gorman3dd28262009-06-16 15:32:00 -07001752 preferred_zone, migratetype);
Mel Gorman11e33f62009-06-16 15:31:57 -07001753
1754 if (!page && gfp_mask & __GFP_NOFAIL)
Jens Axboe8aa7e842009-07-09 14:52:32 +02001755 congestion_wait(BLK_RW_ASYNC, HZ/50);
Mel Gorman11e33f62009-06-16 15:31:57 -07001756 } while (!page && (gfp_mask & __GFP_NOFAIL));
1757
1758 return page;
1759}
1760
1761static inline
1762void wake_all_kswapd(unsigned int order, struct zonelist *zonelist,
1763 enum zone_type high_zoneidx)
1764{
1765 struct zoneref *z;
1766 struct zone *zone;
1767
1768 for_each_zone_zonelist(zone, z, zonelist, high_zoneidx)
1769 wakeup_kswapd(zone, order);
1770}
1771
Peter Zijlstra341ce062009-06-16 15:32:02 -07001772static inline int
1773gfp_to_alloc_flags(gfp_t gfp_mask)
1774{
1775 struct task_struct *p = current;
1776 int alloc_flags = ALLOC_WMARK_MIN | ALLOC_CPUSET;
1777 const gfp_t wait = gfp_mask & __GFP_WAIT;
1778
Mel Gormana56f57f2009-06-16 15:32:02 -07001779 /* __GFP_HIGH is assumed to be the same as ALLOC_HIGH to save a branch. */
1780 BUILD_BUG_ON(__GFP_HIGH != ALLOC_HIGH);
1781
Peter Zijlstra341ce062009-06-16 15:32:02 -07001782 /*
1783 * The caller may dip into page reserves a bit more if the caller
1784 * cannot run direct reclaim, or if the caller has realtime scheduling
1785 * policy or is asking for __GFP_HIGH memory. GFP_ATOMIC requests will
1786 * set both ALLOC_HARDER (!wait) and ALLOC_HIGH (__GFP_HIGH).
1787 */
Mel Gormana56f57f2009-06-16 15:32:02 -07001788 alloc_flags |= (gfp_mask & __GFP_HIGH);
Peter Zijlstra341ce062009-06-16 15:32:02 -07001789
1790 if (!wait) {
1791 alloc_flags |= ALLOC_HARDER;
1792 /*
1793 * Ignore cpuset if GFP_ATOMIC (!wait) rather than fail alloc.
1794 * See also cpuset_zone_allowed() comment in kernel/cpuset.c.
1795 */
1796 alloc_flags &= ~ALLOC_CPUSET;
Mel Gorman9d0ed602009-11-11 14:26:17 -08001797 } else if (unlikely(rt_task(p)) && !in_interrupt())
Peter Zijlstra341ce062009-06-16 15:32:02 -07001798 alloc_flags |= ALLOC_HARDER;
1799
1800 if (likely(!(gfp_mask & __GFP_NOMEMALLOC))) {
1801 if (!in_interrupt() &&
1802 ((p->flags & PF_MEMALLOC) ||
1803 unlikely(test_thread_flag(TIF_MEMDIE))))
1804 alloc_flags |= ALLOC_NO_WATERMARKS;
1805 }
1806
1807 return alloc_flags;
1808}
1809
Mel Gorman11e33f62009-06-16 15:31:57 -07001810static inline struct page *
1811__alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order,
1812 struct zonelist *zonelist, enum zone_type high_zoneidx,
Mel Gorman3dd28262009-06-16 15:32:00 -07001813 nodemask_t *nodemask, struct zone *preferred_zone,
1814 int migratetype)
Mel Gorman11e33f62009-06-16 15:31:57 -07001815{
1816 const gfp_t wait = gfp_mask & __GFP_WAIT;
1817 struct page *page = NULL;
1818 int alloc_flags;
1819 unsigned long pages_reclaimed = 0;
1820 unsigned long did_some_progress;
1821 struct task_struct *p = current;
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001822
Christoph Lameter952f3b52006-12-06 20:33:26 -08001823 /*
Mel Gorman72807a72009-06-16 15:32:18 -07001824 * In the slowpath, we sanity check order to avoid ever trying to
1825 * reclaim >= MAX_ORDER areas which will never succeed. Callers may
1826 * be using allocators in order of preference for an area that is
1827 * too large.
1828 */
Mel Gorman1fc28b72009-07-29 15:04:08 -07001829 if (order >= MAX_ORDER) {
1830 WARN_ON_ONCE(!(gfp_mask & __GFP_NOWARN));
Mel Gorman72807a72009-06-16 15:32:18 -07001831 return NULL;
Mel Gorman1fc28b72009-07-29 15:04:08 -07001832 }
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001833
Christoph Lameter952f3b52006-12-06 20:33:26 -08001834 /*
1835 * GFP_THISNODE (meaning __GFP_THISNODE, __GFP_NORETRY and
1836 * __GFP_NOWARN set) should not cause reclaim since the subsystem
1837 * (f.e. slab) using GFP_THISNODE may choose to trigger reclaim
1838 * using a larger set of nodes after it has established that the
1839 * allowed per node queues are empty and that nodes are
1840 * over allocated.
1841 */
1842 if (NUMA_BUILD && (gfp_mask & GFP_THISNODE) == GFP_THISNODE)
1843 goto nopage;
1844
Mel Gormancc4a6852009-11-11 14:26:14 -08001845restart:
Mel Gorman11e33f62009-06-16 15:31:57 -07001846 wake_all_kswapd(order, zonelist, high_zoneidx);
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001847
Paul Jackson9bf22292005-09-06 15:18:12 -07001848 /*
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001849 * OK, we're below the kswapd watermark and have kicked background
1850 * reclaim. Now things get more complex, so set up alloc_flags according
1851 * to how we want to proceed.
Paul Jackson9bf22292005-09-06 15:18:12 -07001852 */
Peter Zijlstra341ce062009-06-16 15:32:02 -07001853 alloc_flags = gfp_to_alloc_flags(gfp_mask);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001854
Peter Zijlstra341ce062009-06-16 15:32:02 -07001855 /* This is the last chance, in general, before the goto nopage. */
Mel Gorman19770b32008-04-28 02:12:18 -07001856 page = get_page_from_freelist(gfp_mask, nodemask, order, zonelist,
Peter Zijlstra341ce062009-06-16 15:32:02 -07001857 high_zoneidx, alloc_flags & ~ALLOC_NO_WATERMARKS,
1858 preferred_zone, migratetype);
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001859 if (page)
1860 goto got_pg;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001861
Kirill Korotaevb43a57b2006-12-06 20:32:27 -08001862rebalance:
Mel Gorman11e33f62009-06-16 15:31:57 -07001863 /* Allocate without watermarks if the context allows */
Peter Zijlstra341ce062009-06-16 15:32:02 -07001864 if (alloc_flags & ALLOC_NO_WATERMARKS) {
1865 page = __alloc_pages_high_priority(gfp_mask, order,
1866 zonelist, high_zoneidx, nodemask,
1867 preferred_zone, migratetype);
1868 if (page)
1869 goto got_pg;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001870 }
1871
1872 /* Atomic allocations - we can't balance anything */
1873 if (!wait)
1874 goto nopage;
1875
Peter Zijlstra341ce062009-06-16 15:32:02 -07001876 /* Avoid recursion of direct reclaim */
1877 if (p->flags & PF_MEMALLOC)
1878 goto nopage;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001879
David Rientjes6583bb62009-07-29 15:02:06 -07001880 /* Avoid allocations with no watermarks from looping endlessly */
1881 if (test_thread_flag(TIF_MEMDIE) && !(gfp_mask & __GFP_NOFAIL))
1882 goto nopage;
1883
Mel Gorman11e33f62009-06-16 15:31:57 -07001884 /* Try direct reclaim and then allocating */
1885 page = __alloc_pages_direct_reclaim(gfp_mask, order,
1886 zonelist, high_zoneidx,
1887 nodemask,
Mel Gorman5117f452009-06-16 15:31:59 -07001888 alloc_flags, preferred_zone,
Mel Gorman3dd28262009-06-16 15:32:00 -07001889 migratetype, &did_some_progress);
Mel Gorman11e33f62009-06-16 15:31:57 -07001890 if (page)
1891 goto got_pg;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001892
Linus Torvalds1da177e2005-04-16 15:20:36 -07001893 /*
Mel Gorman11e33f62009-06-16 15:31:57 -07001894 * If we failed to make any progress reclaiming, then we are
1895 * running out of options and have to consider going OOM
Linus Torvalds1da177e2005-04-16 15:20:36 -07001896 */
Mel Gorman11e33f62009-06-16 15:31:57 -07001897 if (!did_some_progress) {
1898 if ((gfp_mask & __GFP_FS) && !(gfp_mask & __GFP_NORETRY)) {
Rafael J. Wysocki7f33d492009-06-16 15:32:41 -07001899 if (oom_killer_disabled)
1900 goto nopage;
Mel Gorman11e33f62009-06-16 15:31:57 -07001901 page = __alloc_pages_may_oom(gfp_mask, order,
1902 zonelist, high_zoneidx,
Mel Gorman3dd28262009-06-16 15:32:00 -07001903 nodemask, preferred_zone,
1904 migratetype);
Mel Gorman11e33f62009-06-16 15:31:57 -07001905 if (page)
1906 goto got_pg;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001907
Mel Gorman11e33f62009-06-16 15:31:57 -07001908 /*
David Rientjes82553a92009-06-16 15:32:58 -07001909 * The OOM killer does not trigger for high-order
1910 * ~__GFP_NOFAIL allocations so if no progress is being
1911 * made, there are no other options and retrying is
1912 * unlikely to help.
Mel Gorman11e33f62009-06-16 15:31:57 -07001913 */
David Rientjes82553a92009-06-16 15:32:58 -07001914 if (order > PAGE_ALLOC_COSTLY_ORDER &&
1915 !(gfp_mask & __GFP_NOFAIL))
Mel Gorman11e33f62009-06-16 15:31:57 -07001916 goto nopage;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001917
Linus Torvalds1da177e2005-04-16 15:20:36 -07001918 goto restart;
1919 }
1920 }
1921
Mel Gorman11e33f62009-06-16 15:31:57 -07001922 /* Check if we should retry the allocation */
Nishanth Aravamudana41f24e2008-04-29 00:58:25 -07001923 pages_reclaimed += did_some_progress;
Mel Gorman11e33f62009-06-16 15:31:57 -07001924 if (should_alloc_retry(gfp_mask, order, pages_reclaimed)) {
1925 /* Wait for some write requests to complete then retry */
Jens Axboe8aa7e842009-07-09 14:52:32 +02001926 congestion_wait(BLK_RW_ASYNC, HZ/50);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001927 goto rebalance;
1928 }
1929
1930nopage:
1931 if (!(gfp_mask & __GFP_NOWARN) && printk_ratelimit()) {
1932 printk(KERN_WARNING "%s: page allocation failure."
1933 " order:%d, mode:0x%x\n",
1934 p->comm, order, gfp_mask);
1935 dump_stack();
Janet Morgan578c2fd2005-06-21 17:14:56 -07001936 show_mem();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001937 }
Vegard Nossumb1eeab62008-11-25 16:55:53 +01001938 return page;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001939got_pg:
Vegard Nossumb1eeab62008-11-25 16:55:53 +01001940 if (kmemcheck_enabled)
1941 kmemcheck_pagealloc_alloc(page, order, gfp_mask);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001942 return page;
Mel Gorman11e33f62009-06-16 15:31:57 -07001943
Linus Torvalds1da177e2005-04-16 15:20:36 -07001944}
Mel Gorman11e33f62009-06-16 15:31:57 -07001945
1946/*
1947 * This is the 'heart' of the zoned buddy allocator.
1948 */
1949struct page *
1950__alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
1951 struct zonelist *zonelist, nodemask_t *nodemask)
1952{
1953 enum zone_type high_zoneidx = gfp_zone(gfp_mask);
Mel Gorman5117f452009-06-16 15:31:59 -07001954 struct zone *preferred_zone;
Mel Gorman11e33f62009-06-16 15:31:57 -07001955 struct page *page;
Mel Gorman3dd28262009-06-16 15:32:00 -07001956 int migratetype = allocflags_to_migratetype(gfp_mask);
Mel Gorman11e33f62009-06-16 15:31:57 -07001957
Benjamin Herrenschmidtdcce2842009-06-18 13:24:12 +10001958 gfp_mask &= gfp_allowed_mask;
1959
Mel Gorman11e33f62009-06-16 15:31:57 -07001960 lockdep_trace_alloc(gfp_mask);
1961
1962 might_sleep_if(gfp_mask & __GFP_WAIT);
1963
1964 if (should_fail_alloc_page(gfp_mask, order))
1965 return NULL;
1966
1967 /*
1968 * Check the zones suitable for the gfp_mask contain at least one
1969 * valid zone. It's possible to have an empty zonelist as a result
1970 * of GFP_THISNODE and a memoryless node
1971 */
1972 if (unlikely(!zonelist->_zonerefs->zone))
1973 return NULL;
1974
Mel Gorman5117f452009-06-16 15:31:59 -07001975 /* The preferred zone is used for statistics later */
1976 first_zones_zonelist(zonelist, high_zoneidx, nodemask, &preferred_zone);
1977 if (!preferred_zone)
1978 return NULL;
1979
1980 /* First allocation attempt */
Mel Gorman11e33f62009-06-16 15:31:57 -07001981 page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask, order,
Mel Gorman5117f452009-06-16 15:31:59 -07001982 zonelist, high_zoneidx, ALLOC_WMARK_LOW|ALLOC_CPUSET,
Mel Gorman3dd28262009-06-16 15:32:00 -07001983 preferred_zone, migratetype);
Mel Gorman11e33f62009-06-16 15:31:57 -07001984 if (unlikely(!page))
1985 page = __alloc_pages_slowpath(gfp_mask, order,
Mel Gorman5117f452009-06-16 15:31:59 -07001986 zonelist, high_zoneidx, nodemask,
Mel Gorman3dd28262009-06-16 15:32:00 -07001987 preferred_zone, migratetype);
Mel Gorman11e33f62009-06-16 15:31:57 -07001988
Mel Gorman4b4f2782009-09-21 17:02:41 -07001989 trace_mm_page_alloc(page, order, gfp_mask, migratetype);
Mel Gorman11e33f62009-06-16 15:31:57 -07001990 return page;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001991}
Mel Gormand2391712009-06-16 15:31:52 -07001992EXPORT_SYMBOL(__alloc_pages_nodemask);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001993
1994/*
1995 * Common helper functions.
1996 */
Harvey Harrison920c7a52008-02-04 22:29:26 -08001997unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001998{
Akinobu Mita945a1112009-09-21 17:01:47 -07001999 struct page *page;
2000
2001 /*
2002 * __get_free_pages() returns a 32-bit address, which cannot represent
2003 * a highmem page
2004 */
2005 VM_BUG_ON((gfp_mask & __GFP_HIGHMEM) != 0);
2006
Linus Torvalds1da177e2005-04-16 15:20:36 -07002007 page = alloc_pages(gfp_mask, order);
2008 if (!page)
2009 return 0;
2010 return (unsigned long) page_address(page);
2011}
Linus Torvalds1da177e2005-04-16 15:20:36 -07002012EXPORT_SYMBOL(__get_free_pages);
2013
Harvey Harrison920c7a52008-02-04 22:29:26 -08002014unsigned long get_zeroed_page(gfp_t gfp_mask)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002015{
Akinobu Mita945a1112009-09-21 17:01:47 -07002016 return __get_free_pages(gfp_mask | __GFP_ZERO, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002017}
Linus Torvalds1da177e2005-04-16 15:20:36 -07002018EXPORT_SYMBOL(get_zeroed_page);
2019
2020void __pagevec_free(struct pagevec *pvec)
2021{
2022 int i = pagevec_count(pvec);
2023
Mel Gorman4b4f2782009-09-21 17:02:41 -07002024 while (--i >= 0) {
2025 trace_mm_pagevec_free(pvec->pages[i], pvec->cold);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002026 free_hot_cold_page(pvec->pages[i], pvec->cold);
Mel Gorman4b4f2782009-09-21 17:02:41 -07002027 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002028}
2029
Harvey Harrison920c7a52008-02-04 22:29:26 -08002030void __free_pages(struct page *page, unsigned int order)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002031{
Nick Pigginb5810032005-10-29 18:16:12 -07002032 if (put_page_testzero(page)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002033 if (order == 0)
Li Hongfc916682010-03-05 13:41:54 -08002034 free_hot_cold_page(page, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002035 else
2036 __free_pages_ok(page, order);
2037 }
2038}
2039
2040EXPORT_SYMBOL(__free_pages);
2041
Harvey Harrison920c7a52008-02-04 22:29:26 -08002042void free_pages(unsigned long addr, unsigned int order)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002043{
2044 if (addr != 0) {
Nick Piggin725d7042006-09-25 23:30:55 -07002045 VM_BUG_ON(!virt_addr_valid((void *)addr));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002046 __free_pages(virt_to_page((void *)addr), order);
2047 }
2048}
2049
2050EXPORT_SYMBOL(free_pages);
2051
Timur Tabi2be0ffe2008-07-23 21:28:11 -07002052/**
2053 * alloc_pages_exact - allocate an exact number physically-contiguous pages.
2054 * @size: the number of bytes to allocate
2055 * @gfp_mask: GFP flags for the allocation
2056 *
2057 * This function is similar to alloc_pages(), except that it allocates the
2058 * minimum number of pages to satisfy the request. alloc_pages() can only
2059 * allocate memory in power-of-two pages.
2060 *
2061 * This function is also limited by MAX_ORDER.
2062 *
2063 * Memory allocated by this function must be released by free_pages_exact().
2064 */
2065void *alloc_pages_exact(size_t size, gfp_t gfp_mask)
2066{
2067 unsigned int order = get_order(size);
2068 unsigned long addr;
2069
2070 addr = __get_free_pages(gfp_mask, order);
2071 if (addr) {
2072 unsigned long alloc_end = addr + (PAGE_SIZE << order);
2073 unsigned long used = addr + PAGE_ALIGN(size);
2074
Kevin Cernekee5bfd7562009-07-05 12:08:19 -07002075 split_page(virt_to_page((void *)addr), order);
Timur Tabi2be0ffe2008-07-23 21:28:11 -07002076 while (used < alloc_end) {
2077 free_page(used);
2078 used += PAGE_SIZE;
2079 }
2080 }
2081
2082 return (void *)addr;
2083}
2084EXPORT_SYMBOL(alloc_pages_exact);
2085
2086/**
2087 * free_pages_exact - release memory allocated via alloc_pages_exact()
2088 * @virt: the value returned by alloc_pages_exact.
2089 * @size: size of allocation, same value as passed to alloc_pages_exact().
2090 *
2091 * Release the memory allocated by a previous call to alloc_pages_exact.
2092 */
2093void free_pages_exact(void *virt, size_t size)
2094{
2095 unsigned long addr = (unsigned long)virt;
2096 unsigned long end = addr + PAGE_ALIGN(size);
2097
2098 while (addr < end) {
2099 free_page(addr);
2100 addr += PAGE_SIZE;
2101 }
2102}
2103EXPORT_SYMBOL(free_pages_exact);
2104
Linus Torvalds1da177e2005-04-16 15:20:36 -07002105static unsigned int nr_free_zone_pages(int offset)
2106{
Mel Gormandd1a2392008-04-28 02:12:17 -07002107 struct zoneref *z;
Mel Gorman54a6eb52008-04-28 02:12:16 -07002108 struct zone *zone;
2109
Martin J. Blighe310fd42005-07-29 22:59:18 -07002110 /* Just pick one node, since fallback list is circular */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002111 unsigned int sum = 0;
2112
Mel Gorman0e884602008-04-28 02:12:14 -07002113 struct zonelist *zonelist = node_zonelist(numa_node_id(), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002114
Mel Gorman54a6eb52008-04-28 02:12:16 -07002115 for_each_zone_zonelist(zone, z, zonelist, offset) {
Martin J. Blighe310fd42005-07-29 22:59:18 -07002116 unsigned long size = zone->present_pages;
Mel Gorman41858962009-06-16 15:32:12 -07002117 unsigned long high = high_wmark_pages(zone);
Martin J. Blighe310fd42005-07-29 22:59:18 -07002118 if (size > high)
2119 sum += size - high;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002120 }
2121
2122 return sum;
2123}
2124
2125/*
2126 * Amount of free RAM allocatable within ZONE_DMA and ZONE_NORMAL
2127 */
2128unsigned int nr_free_buffer_pages(void)
2129{
Al Viroaf4ca452005-10-21 02:55:38 -04002130 return nr_free_zone_pages(gfp_zone(GFP_USER));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002131}
Meelap Shahc2f1a552007-07-17 04:04:39 -07002132EXPORT_SYMBOL_GPL(nr_free_buffer_pages);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002133
2134/*
2135 * Amount of free RAM allocatable within all zones
2136 */
2137unsigned int nr_free_pagecache_pages(void)
2138{
Mel Gorman2a1e2742007-07-17 04:03:12 -07002139 return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002140}
Christoph Lameter08e0f6a2006-09-27 01:50:06 -07002141
2142static inline void show_node(struct zone *zone)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002143{
Christoph Lameter08e0f6a2006-09-27 01:50:06 -07002144 if (NUMA_BUILD)
Andy Whitcroft25ba77c2006-12-06 20:33:03 -08002145 printk("Node %d ", zone_to_nid(zone));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002146}
Linus Torvalds1da177e2005-04-16 15:20:36 -07002147
Linus Torvalds1da177e2005-04-16 15:20:36 -07002148void si_meminfo(struct sysinfo *val)
2149{
2150 val->totalram = totalram_pages;
2151 val->sharedram = 0;
Christoph Lameterd23ad422007-02-10 01:43:02 -08002152 val->freeram = global_page_state(NR_FREE_PAGES);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002153 val->bufferram = nr_blockdev_pages();
Linus Torvalds1da177e2005-04-16 15:20:36 -07002154 val->totalhigh = totalhigh_pages;
2155 val->freehigh = nr_free_highpages();
Linus Torvalds1da177e2005-04-16 15:20:36 -07002156 val->mem_unit = PAGE_SIZE;
2157}
2158
2159EXPORT_SYMBOL(si_meminfo);
2160
2161#ifdef CONFIG_NUMA
2162void si_meminfo_node(struct sysinfo *val, int nid)
2163{
2164 pg_data_t *pgdat = NODE_DATA(nid);
2165
2166 val->totalram = pgdat->node_present_pages;
Christoph Lameterd23ad422007-02-10 01:43:02 -08002167 val->freeram = node_page_state(nid, NR_FREE_PAGES);
Christoph Lameter98d2b0e2006-09-25 23:31:12 -07002168#ifdef CONFIG_HIGHMEM
Linus Torvalds1da177e2005-04-16 15:20:36 -07002169 val->totalhigh = pgdat->node_zones[ZONE_HIGHMEM].present_pages;
Christoph Lameterd23ad422007-02-10 01:43:02 -08002170 val->freehigh = zone_page_state(&pgdat->node_zones[ZONE_HIGHMEM],
2171 NR_FREE_PAGES);
Christoph Lameter98d2b0e2006-09-25 23:31:12 -07002172#else
2173 val->totalhigh = 0;
2174 val->freehigh = 0;
2175#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07002176 val->mem_unit = PAGE_SIZE;
2177}
2178#endif
2179
2180#define K(x) ((x) << (PAGE_SHIFT-10))
2181
2182/*
2183 * Show free area list (used inside shift_scroll-lock stuff)
2184 * We also calculate the percentage fragmentation. We do this by counting the
2185 * memory on each free list with the exception of the first item on the list.
2186 */
2187void show_free_areas(void)
2188{
Jes Sorensenc7241912006-09-27 01:50:05 -07002189 int cpu;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002190 struct zone *zone;
2191
KOSAKI Motohiroee99c712009-03-31 15:19:31 -07002192 for_each_populated_zone(zone) {
Jes Sorensenc7241912006-09-27 01:50:05 -07002193 show_node(zone);
2194 printk("%s per-cpu:\n", zone->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002195
Dave Jones6b482c62005-11-10 15:45:56 -05002196 for_each_online_cpu(cpu) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002197 struct per_cpu_pageset *pageset;
2198
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09002199 pageset = per_cpu_ptr(zone->pageset, cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002200
Christoph Lameter3dfa5722008-02-04 22:29:19 -08002201 printk("CPU %4d: hi:%5d, btch:%4d usd:%4d\n",
2202 cpu, pageset->pcp.high,
2203 pageset->pcp.batch, pageset->pcp.count);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002204 }
2205 }
2206
KOSAKI Motohiroa7312862009-09-21 17:01:37 -07002207 printk("active_anon:%lu inactive_anon:%lu isolated_anon:%lu\n"
2208 " active_file:%lu inactive_file:%lu isolated_file:%lu\n"
Lee Schermerhorn7b854122008-10-18 20:26:40 -07002209 " unevictable:%lu"
Andrew Mortonb76146e2009-10-26 16:49:52 -07002210 " dirty:%lu writeback:%lu unstable:%lu\n"
KOSAKI Motohiro3701b032009-09-21 17:01:29 -07002211 " free:%lu slab_reclaimable:%lu slab_unreclaimable:%lu\n"
KOSAKI Motohiro4b021082009-09-21 17:01:33 -07002212 " mapped:%lu shmem:%lu pagetables:%lu bounce:%lu\n",
Rik van Riel4f98a2f2008-10-18 20:26:32 -07002213 global_page_state(NR_ACTIVE_ANON),
Rik van Riel4f98a2f2008-10-18 20:26:32 -07002214 global_page_state(NR_INACTIVE_ANON),
KOSAKI Motohiroa7312862009-09-21 17:01:37 -07002215 global_page_state(NR_ISOLATED_ANON),
2216 global_page_state(NR_ACTIVE_FILE),
Rik van Riel4f98a2f2008-10-18 20:26:32 -07002217 global_page_state(NR_INACTIVE_FILE),
KOSAKI Motohiroa7312862009-09-21 17:01:37 -07002218 global_page_state(NR_ISOLATED_FILE),
Lee Schermerhorn7b854122008-10-18 20:26:40 -07002219 global_page_state(NR_UNEVICTABLE),
Christoph Lameterb1e7a8f2006-06-30 01:55:39 -07002220 global_page_state(NR_FILE_DIRTY),
Christoph Lameterce866b32006-06-30 01:55:40 -07002221 global_page_state(NR_WRITEBACK),
Christoph Lameterfd39fc82006-06-30 01:55:40 -07002222 global_page_state(NR_UNSTABLE_NFS),
Christoph Lameterd23ad422007-02-10 01:43:02 -08002223 global_page_state(NR_FREE_PAGES),
KOSAKI Motohiro3701b032009-09-21 17:01:29 -07002224 global_page_state(NR_SLAB_RECLAIMABLE),
2225 global_page_state(NR_SLAB_UNRECLAIMABLE),
Christoph Lameter65ba55f2006-06-30 01:55:34 -07002226 global_page_state(NR_FILE_MAPPED),
KOSAKI Motohiro4b021082009-09-21 17:01:33 -07002227 global_page_state(NR_SHMEM),
Andrew Mortona25700a2007-02-08 14:20:40 -08002228 global_page_state(NR_PAGETABLE),
2229 global_page_state(NR_BOUNCE));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002230
KOSAKI Motohiroee99c712009-03-31 15:19:31 -07002231 for_each_populated_zone(zone) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002232 int i;
2233
2234 show_node(zone);
2235 printk("%s"
2236 " free:%lukB"
2237 " min:%lukB"
2238 " low:%lukB"
2239 " high:%lukB"
Rik van Riel4f98a2f2008-10-18 20:26:32 -07002240 " active_anon:%lukB"
2241 " inactive_anon:%lukB"
2242 " active_file:%lukB"
2243 " inactive_file:%lukB"
Lee Schermerhorn7b854122008-10-18 20:26:40 -07002244 " unevictable:%lukB"
KOSAKI Motohiroa7312862009-09-21 17:01:37 -07002245 " isolated(anon):%lukB"
2246 " isolated(file):%lukB"
Linus Torvalds1da177e2005-04-16 15:20:36 -07002247 " present:%lukB"
KOSAKI Motohiro4a0aa732009-09-21 17:01:30 -07002248 " mlocked:%lukB"
2249 " dirty:%lukB"
2250 " writeback:%lukB"
2251 " mapped:%lukB"
KOSAKI Motohiro4b021082009-09-21 17:01:33 -07002252 " shmem:%lukB"
KOSAKI Motohiro4a0aa732009-09-21 17:01:30 -07002253 " slab_reclaimable:%lukB"
2254 " slab_unreclaimable:%lukB"
KOSAKI Motohiroc6a7f572009-09-21 17:01:32 -07002255 " kernel_stack:%lukB"
KOSAKI Motohiro4a0aa732009-09-21 17:01:30 -07002256 " pagetables:%lukB"
2257 " unstable:%lukB"
2258 " bounce:%lukB"
2259 " writeback_tmp:%lukB"
Linus Torvalds1da177e2005-04-16 15:20:36 -07002260 " pages_scanned:%lu"
2261 " all_unreclaimable? %s"
2262 "\n",
2263 zone->name,
Christoph Lameterd23ad422007-02-10 01:43:02 -08002264 K(zone_page_state(zone, NR_FREE_PAGES)),
Mel Gorman41858962009-06-16 15:32:12 -07002265 K(min_wmark_pages(zone)),
2266 K(low_wmark_pages(zone)),
2267 K(high_wmark_pages(zone)),
Rik van Riel4f98a2f2008-10-18 20:26:32 -07002268 K(zone_page_state(zone, NR_ACTIVE_ANON)),
2269 K(zone_page_state(zone, NR_INACTIVE_ANON)),
2270 K(zone_page_state(zone, NR_ACTIVE_FILE)),
2271 K(zone_page_state(zone, NR_INACTIVE_FILE)),
Lee Schermerhorn7b854122008-10-18 20:26:40 -07002272 K(zone_page_state(zone, NR_UNEVICTABLE)),
KOSAKI Motohiroa7312862009-09-21 17:01:37 -07002273 K(zone_page_state(zone, NR_ISOLATED_ANON)),
2274 K(zone_page_state(zone, NR_ISOLATED_FILE)),
Linus Torvalds1da177e2005-04-16 15:20:36 -07002275 K(zone->present_pages),
KOSAKI Motohiro4a0aa732009-09-21 17:01:30 -07002276 K(zone_page_state(zone, NR_MLOCK)),
2277 K(zone_page_state(zone, NR_FILE_DIRTY)),
2278 K(zone_page_state(zone, NR_WRITEBACK)),
2279 K(zone_page_state(zone, NR_FILE_MAPPED)),
KOSAKI Motohiro4b021082009-09-21 17:01:33 -07002280 K(zone_page_state(zone, NR_SHMEM)),
KOSAKI Motohiro4a0aa732009-09-21 17:01:30 -07002281 K(zone_page_state(zone, NR_SLAB_RECLAIMABLE)),
2282 K(zone_page_state(zone, NR_SLAB_UNRECLAIMABLE)),
KOSAKI Motohiroc6a7f572009-09-21 17:01:32 -07002283 zone_page_state(zone, NR_KERNEL_STACK) *
2284 THREAD_SIZE / 1024,
KOSAKI Motohiro4a0aa732009-09-21 17:01:30 -07002285 K(zone_page_state(zone, NR_PAGETABLE)),
2286 K(zone_page_state(zone, NR_UNSTABLE_NFS)),
2287 K(zone_page_state(zone, NR_BOUNCE)),
2288 K(zone_page_state(zone, NR_WRITEBACK_TEMP)),
Linus Torvalds1da177e2005-04-16 15:20:36 -07002289 zone->pages_scanned,
KOSAKI Motohiro93e4a892010-03-05 13:41:55 -08002290 (zone->all_unreclaimable ? "yes" : "no")
Linus Torvalds1da177e2005-04-16 15:20:36 -07002291 );
2292 printk("lowmem_reserve[]:");
2293 for (i = 0; i < MAX_NR_ZONES; i++)
2294 printk(" %lu", zone->lowmem_reserve[i]);
2295 printk("\n");
2296 }
2297
KOSAKI Motohiroee99c712009-03-31 15:19:31 -07002298 for_each_populated_zone(zone) {
Kirill Korotaev8f9de512006-06-23 02:03:50 -07002299 unsigned long nr[MAX_ORDER], flags, order, total = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002300
2301 show_node(zone);
2302 printk("%s: ", zone->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002303
2304 spin_lock_irqsave(&zone->lock, flags);
2305 for (order = 0; order < MAX_ORDER; order++) {
Kirill Korotaev8f9de512006-06-23 02:03:50 -07002306 nr[order] = zone->free_area[order].nr_free;
2307 total += nr[order] << order;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002308 }
2309 spin_unlock_irqrestore(&zone->lock, flags);
Kirill Korotaev8f9de512006-06-23 02:03:50 -07002310 for (order = 0; order < MAX_ORDER; order++)
2311 printk("%lu*%lukB ", nr[order], K(1UL) << order);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002312 printk("= %lukB\n", K(total));
2313 }
2314
Larry Woodmane6f36022008-02-04 22:29:30 -08002315 printk("%ld total pagecache pages\n", global_page_state(NR_FILE_PAGES));
2316
Linus Torvalds1da177e2005-04-16 15:20:36 -07002317 show_swap_cache_info();
2318}
2319
Mel Gorman19770b32008-04-28 02:12:18 -07002320static void zoneref_set_zone(struct zone *zone, struct zoneref *zoneref)
2321{
2322 zoneref->zone = zone;
2323 zoneref->zone_idx = zone_idx(zone);
2324}
2325
Linus Torvalds1da177e2005-04-16 15:20:36 -07002326/*
2327 * Builds allocation fallback zone lists.
Christoph Lameter1a932052006-01-06 00:11:16 -08002328 *
2329 * Add all populated zones of a node to the zonelist.
Linus Torvalds1da177e2005-04-16 15:20:36 -07002330 */
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002331static int build_zonelists_node(pg_data_t *pgdat, struct zonelist *zonelist,
2332 int nr_zones, enum zone_type zone_type)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002333{
Christoph Lameter1a932052006-01-06 00:11:16 -08002334 struct zone *zone;
2335
Christoph Lameter98d2b0e2006-09-25 23:31:12 -07002336 BUG_ON(zone_type >= MAX_NR_ZONES);
Christoph Lameter2f6726e2006-09-25 23:31:18 -07002337 zone_type++;
Christoph Lameter02a68a52006-01-06 00:11:18 -08002338
2339 do {
Christoph Lameter2f6726e2006-09-25 23:31:18 -07002340 zone_type--;
Christoph Lameter070f8032006-01-06 00:11:19 -08002341 zone = pgdat->node_zones + zone_type;
Christoph Lameter1a932052006-01-06 00:11:16 -08002342 if (populated_zone(zone)) {
Mel Gormandd1a2392008-04-28 02:12:17 -07002343 zoneref_set_zone(zone,
2344 &zonelist->_zonerefs[nr_zones++]);
Christoph Lameter070f8032006-01-06 00:11:19 -08002345 check_highest_zone(zone_type);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002346 }
Christoph Lameter02a68a52006-01-06 00:11:18 -08002347
Christoph Lameter2f6726e2006-09-25 23:31:18 -07002348 } while (zone_type);
Christoph Lameter070f8032006-01-06 00:11:19 -08002349 return nr_zones;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002350}
2351
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002352
2353/*
2354 * zonelist_order:
2355 * 0 = automatic detection of better ordering.
2356 * 1 = order by ([node] distance, -zonetype)
2357 * 2 = order by (-zonetype, [node] distance)
2358 *
2359 * If not NUMA, ZONELIST_ORDER_ZONE and ZONELIST_ORDER_NODE will create
2360 * the same zonelist. So only NUMA can configure this param.
2361 */
2362#define ZONELIST_ORDER_DEFAULT 0
2363#define ZONELIST_ORDER_NODE 1
2364#define ZONELIST_ORDER_ZONE 2
2365
2366/* zonelist order in the kernel.
2367 * set_zonelist_order() will set this to NODE or ZONE.
2368 */
2369static int current_zonelist_order = ZONELIST_ORDER_DEFAULT;
2370static char zonelist_order_name[3][8] = {"Default", "Node", "Zone"};
2371
2372
Linus Torvalds1da177e2005-04-16 15:20:36 -07002373#ifdef CONFIG_NUMA
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002374/* The value user specified ....changed by config */
2375static int user_zonelist_order = ZONELIST_ORDER_DEFAULT;
2376/* string for sysctl */
2377#define NUMA_ZONELIST_ORDER_LEN 16
2378char numa_zonelist_order[16] = "default";
2379
2380/*
2381 * interface for configure zonelist ordering.
2382 * command line option "numa_zonelist_order"
2383 * = "[dD]efault - default, automatic configuration.
2384 * = "[nN]ode - order by node locality, then by zone within node
2385 * = "[zZ]one - order by zone, then by locality within zone
2386 */
2387
2388static int __parse_numa_zonelist_order(char *s)
2389{
2390 if (*s == 'd' || *s == 'D') {
2391 user_zonelist_order = ZONELIST_ORDER_DEFAULT;
2392 } else if (*s == 'n' || *s == 'N') {
2393 user_zonelist_order = ZONELIST_ORDER_NODE;
2394 } else if (*s == 'z' || *s == 'Z') {
2395 user_zonelist_order = ZONELIST_ORDER_ZONE;
2396 } else {
2397 printk(KERN_WARNING
2398 "Ignoring invalid numa_zonelist_order value: "
2399 "%s\n", s);
2400 return -EINVAL;
2401 }
2402 return 0;
2403}
2404
2405static __init int setup_numa_zonelist_order(char *s)
2406{
2407 if (s)
2408 return __parse_numa_zonelist_order(s);
2409 return 0;
2410}
2411early_param("numa_zonelist_order", setup_numa_zonelist_order);
2412
2413/*
2414 * sysctl handler for numa_zonelist_order
2415 */
2416int numa_zonelist_order_handler(ctl_table *table, int write,
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07002417 void __user *buffer, size_t *length,
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002418 loff_t *ppos)
2419{
2420 char saved_string[NUMA_ZONELIST_ORDER_LEN];
2421 int ret;
Andi Kleen443c6f12009-12-23 21:00:47 +01002422 static DEFINE_MUTEX(zl_order_mutex);
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002423
Andi Kleen443c6f12009-12-23 21:00:47 +01002424 mutex_lock(&zl_order_mutex);
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002425 if (write)
Andi Kleen443c6f12009-12-23 21:00:47 +01002426 strcpy(saved_string, (char*)table->data);
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07002427 ret = proc_dostring(table, write, buffer, length, ppos);
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002428 if (ret)
Andi Kleen443c6f12009-12-23 21:00:47 +01002429 goto out;
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002430 if (write) {
2431 int oldval = user_zonelist_order;
2432 if (__parse_numa_zonelist_order((char*)table->data)) {
2433 /*
2434 * bogus value. restore saved string
2435 */
2436 strncpy((char*)table->data, saved_string,
2437 NUMA_ZONELIST_ORDER_LEN);
2438 user_zonelist_order = oldval;
2439 } else if (oldval != user_zonelist_order)
2440 build_all_zonelists();
2441 }
Andi Kleen443c6f12009-12-23 21:00:47 +01002442out:
2443 mutex_unlock(&zl_order_mutex);
2444 return ret;
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002445}
2446
2447
Christoph Lameter62bc62a2009-06-16 15:32:15 -07002448#define MAX_NODE_LOAD (nr_online_nodes)
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002449static int node_load[MAX_NUMNODES];
2450
Linus Torvalds1da177e2005-04-16 15:20:36 -07002451/**
Pavel Pisa4dc3b162005-05-01 08:59:25 -07002452 * 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 -07002453 * @node: node whose fallback list we're appending
2454 * @used_node_mask: nodemask_t of already used nodes
2455 *
2456 * We use a number of factors to determine which is the next node that should
2457 * appear on a given node's fallback list. The node should not have appeared
2458 * already in @node's fallback list, and it should be the next closest node
2459 * according to the distance array (which contains arbitrary distance values
2460 * from each node to each node in the system), and should also prefer nodes
2461 * with no CPUs, since presumably they'll have very little allocation pressure
2462 * on them otherwise.
2463 * It returns -1 if no node is found.
2464 */
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002465static int find_next_best_node(int node, nodemask_t *used_node_mask)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002466{
Linus Torvalds4cf808e2006-02-17 20:38:21 +01002467 int n, val;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002468 int min_val = INT_MAX;
2469 int best_node = -1;
Rusty Russella70f7302009-03-13 14:49:46 +10302470 const struct cpumask *tmp = cpumask_of_node(0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002471
Linus Torvalds4cf808e2006-02-17 20:38:21 +01002472 /* Use the local node if we haven't already */
2473 if (!node_isset(node, *used_node_mask)) {
2474 node_set(node, *used_node_mask);
2475 return node;
2476 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002477
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07002478 for_each_node_state(n, N_HIGH_MEMORY) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002479
2480 /* Don't want a node to appear more than once */
2481 if (node_isset(n, *used_node_mask))
2482 continue;
2483
Linus Torvalds1da177e2005-04-16 15:20:36 -07002484 /* Use the distance array to find the distance */
2485 val = node_distance(node, n);
2486
Linus Torvalds4cf808e2006-02-17 20:38:21 +01002487 /* Penalize nodes under us ("prefer the next node") */
2488 val += (n < node);
2489
Linus Torvalds1da177e2005-04-16 15:20:36 -07002490 /* Give preference to headless and unused nodes */
Rusty Russella70f7302009-03-13 14:49:46 +10302491 tmp = cpumask_of_node(n);
2492 if (!cpumask_empty(tmp))
Linus Torvalds1da177e2005-04-16 15:20:36 -07002493 val += PENALTY_FOR_NODE_WITH_CPUS;
2494
2495 /* Slight preference for less loaded node */
2496 val *= (MAX_NODE_LOAD*MAX_NUMNODES);
2497 val += node_load[n];
2498
2499 if (val < min_val) {
2500 min_val = val;
2501 best_node = n;
2502 }
2503 }
2504
2505 if (best_node >= 0)
2506 node_set(best_node, *used_node_mask);
2507
2508 return best_node;
2509}
2510
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002511
2512/*
2513 * Build zonelists ordered by node and zones within node.
2514 * This results in maximum locality--normal zone overflows into local
2515 * DMA zone, if any--but risks exhausting DMA zone.
2516 */
2517static void build_zonelists_in_node_order(pg_data_t *pgdat, int node)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002518{
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002519 int j;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002520 struct zonelist *zonelist;
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002521
Mel Gorman54a6eb52008-04-28 02:12:16 -07002522 zonelist = &pgdat->node_zonelists[0];
Mel Gormandd1a2392008-04-28 02:12:17 -07002523 for (j = 0; zonelist->_zonerefs[j].zone != NULL; j++)
Mel Gorman54a6eb52008-04-28 02:12:16 -07002524 ;
2525 j = build_zonelists_node(NODE_DATA(node), zonelist, j,
2526 MAX_NR_ZONES - 1);
Mel Gormandd1a2392008-04-28 02:12:17 -07002527 zonelist->_zonerefs[j].zone = NULL;
2528 zonelist->_zonerefs[j].zone_idx = 0;
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002529}
2530
2531/*
Christoph Lameter523b9452007-10-16 01:25:37 -07002532 * Build gfp_thisnode zonelists
2533 */
2534static void build_thisnode_zonelists(pg_data_t *pgdat)
2535{
Christoph Lameter523b9452007-10-16 01:25:37 -07002536 int j;
2537 struct zonelist *zonelist;
2538
Mel Gorman54a6eb52008-04-28 02:12:16 -07002539 zonelist = &pgdat->node_zonelists[1];
2540 j = build_zonelists_node(pgdat, zonelist, 0, MAX_NR_ZONES - 1);
Mel Gormandd1a2392008-04-28 02:12:17 -07002541 zonelist->_zonerefs[j].zone = NULL;
2542 zonelist->_zonerefs[j].zone_idx = 0;
Christoph Lameter523b9452007-10-16 01:25:37 -07002543}
2544
2545/*
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002546 * Build zonelists ordered by zone and nodes within zones.
2547 * This results in conserving DMA zone[s] until all Normal memory is
2548 * exhausted, but results in overflowing to remote node while memory
2549 * may still exist in local DMA zone.
2550 */
2551static int node_order[MAX_NUMNODES];
2552
2553static void build_zonelists_in_zone_order(pg_data_t *pgdat, int nr_nodes)
2554{
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002555 int pos, j, node;
2556 int zone_type; /* needs to be signed */
2557 struct zone *z;
2558 struct zonelist *zonelist;
2559
Mel Gorman54a6eb52008-04-28 02:12:16 -07002560 zonelist = &pgdat->node_zonelists[0];
2561 pos = 0;
2562 for (zone_type = MAX_NR_ZONES - 1; zone_type >= 0; zone_type--) {
2563 for (j = 0; j < nr_nodes; j++) {
2564 node = node_order[j];
2565 z = &NODE_DATA(node)->node_zones[zone_type];
2566 if (populated_zone(z)) {
Mel Gormandd1a2392008-04-28 02:12:17 -07002567 zoneref_set_zone(z,
2568 &zonelist->_zonerefs[pos++]);
Mel Gorman54a6eb52008-04-28 02:12:16 -07002569 check_highest_zone(zone_type);
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002570 }
2571 }
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002572 }
Mel Gormandd1a2392008-04-28 02:12:17 -07002573 zonelist->_zonerefs[pos].zone = NULL;
2574 zonelist->_zonerefs[pos].zone_idx = 0;
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002575}
2576
2577static int default_zonelist_order(void)
2578{
2579 int nid, zone_type;
2580 unsigned long low_kmem_size,total_size;
2581 struct zone *z;
2582 int average_size;
2583 /*
2584 * ZONE_DMA and ZONE_DMA32 can be very small area in the sytem.
2585 * If they are really small and used heavily, the system can fall
2586 * into OOM very easily.
2587 * This function detect ZONE_DMA/DMA32 size and confgigures zone order.
2588 */
2589 /* Is there ZONE_NORMAL ? (ex. ppc has only DMA zone..) */
2590 low_kmem_size = 0;
2591 total_size = 0;
2592 for_each_online_node(nid) {
2593 for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++) {
2594 z = &NODE_DATA(nid)->node_zones[zone_type];
2595 if (populated_zone(z)) {
2596 if (zone_type < ZONE_NORMAL)
2597 low_kmem_size += z->present_pages;
2598 total_size += z->present_pages;
2599 }
2600 }
2601 }
2602 if (!low_kmem_size || /* there are no DMA area. */
2603 low_kmem_size > total_size/2) /* DMA/DMA32 is big. */
2604 return ZONELIST_ORDER_NODE;
2605 /*
2606 * look into each node's config.
2607 * If there is a node whose DMA/DMA32 memory is very big area on
2608 * local memory, NODE_ORDER may be suitable.
2609 */
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07002610 average_size = total_size /
2611 (nodes_weight(node_states[N_HIGH_MEMORY]) + 1);
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002612 for_each_online_node(nid) {
2613 low_kmem_size = 0;
2614 total_size = 0;
2615 for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++) {
2616 z = &NODE_DATA(nid)->node_zones[zone_type];
2617 if (populated_zone(z)) {
2618 if (zone_type < ZONE_NORMAL)
2619 low_kmem_size += z->present_pages;
2620 total_size += z->present_pages;
2621 }
2622 }
2623 if (low_kmem_size &&
2624 total_size > average_size && /* ignore small node */
2625 low_kmem_size > total_size * 70/100)
2626 return ZONELIST_ORDER_NODE;
2627 }
2628 return ZONELIST_ORDER_ZONE;
2629}
2630
2631static void set_zonelist_order(void)
2632{
2633 if (user_zonelist_order == ZONELIST_ORDER_DEFAULT)
2634 current_zonelist_order = default_zonelist_order();
2635 else
2636 current_zonelist_order = user_zonelist_order;
2637}
2638
2639static void build_zonelists(pg_data_t *pgdat)
2640{
2641 int j, node, load;
2642 enum zone_type i;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002643 nodemask_t used_mask;
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002644 int local_node, prev_node;
2645 struct zonelist *zonelist;
2646 int order = current_zonelist_order;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002647
2648 /* initialize zonelists */
Christoph Lameter523b9452007-10-16 01:25:37 -07002649 for (i = 0; i < MAX_ZONELISTS; i++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002650 zonelist = pgdat->node_zonelists + i;
Mel Gormandd1a2392008-04-28 02:12:17 -07002651 zonelist->_zonerefs[0].zone = NULL;
2652 zonelist->_zonerefs[0].zone_idx = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002653 }
2654
2655 /* NUMA-aware ordering of nodes */
2656 local_node = pgdat->node_id;
Christoph Lameter62bc62a2009-06-16 15:32:15 -07002657 load = nr_online_nodes;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002658 prev_node = local_node;
2659 nodes_clear(used_mask);
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002660
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002661 memset(node_order, 0, sizeof(node_order));
2662 j = 0;
2663
Linus Torvalds1da177e2005-04-16 15:20:36 -07002664 while ((node = find_next_best_node(local_node, &used_mask)) >= 0) {
Christoph Lameter9eeff232006-01-18 17:42:31 -08002665 int distance = node_distance(local_node, node);
2666
2667 /*
2668 * If another node is sufficiently far away then it is better
2669 * to reclaim pages in a zone before going off node.
2670 */
2671 if (distance > RECLAIM_DISTANCE)
2672 zone_reclaim_mode = 1;
2673
Linus Torvalds1da177e2005-04-16 15:20:36 -07002674 /*
2675 * We don't want to pressure a particular node.
2676 * So adding penalty to the first node in same
2677 * distance group to make it round-robin.
2678 */
Christoph Lameter9eeff232006-01-18 17:42:31 -08002679 if (distance != node_distance(local_node, prev_node))
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002680 node_load[node] = load;
2681
Linus Torvalds1da177e2005-04-16 15:20:36 -07002682 prev_node = node;
2683 load--;
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002684 if (order == ZONELIST_ORDER_NODE)
2685 build_zonelists_in_node_order(pgdat, node);
2686 else
2687 node_order[j++] = node; /* remember order */
2688 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002689
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002690 if (order == ZONELIST_ORDER_ZONE) {
2691 /* calculate node order -- i.e., DMA last! */
2692 build_zonelists_in_zone_order(pgdat, j);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002693 }
Christoph Lameter523b9452007-10-16 01:25:37 -07002694
2695 build_thisnode_zonelists(pgdat);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002696}
2697
Paul Jackson9276b1bc2006-12-06 20:31:48 -08002698/* Construct the zonelist performance cache - see further mmzone.h */
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002699static void build_zonelist_cache(pg_data_t *pgdat)
Paul Jackson9276b1bc2006-12-06 20:31:48 -08002700{
Mel Gorman54a6eb52008-04-28 02:12:16 -07002701 struct zonelist *zonelist;
2702 struct zonelist_cache *zlc;
Mel Gormandd1a2392008-04-28 02:12:17 -07002703 struct zoneref *z;
Paul Jackson9276b1bc2006-12-06 20:31:48 -08002704
Mel Gorman54a6eb52008-04-28 02:12:16 -07002705 zonelist = &pgdat->node_zonelists[0];
2706 zonelist->zlcache_ptr = zlc = &zonelist->zlcache;
2707 bitmap_zero(zlc->fullzones, MAX_ZONES_PER_ZONELIST);
Mel Gormandd1a2392008-04-28 02:12:17 -07002708 for (z = zonelist->_zonerefs; z->zone; z++)
2709 zlc->z_to_n[z - zonelist->_zonerefs] = zonelist_node_idx(z);
Paul Jackson9276b1bc2006-12-06 20:31:48 -08002710}
2711
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002712
Linus Torvalds1da177e2005-04-16 15:20:36 -07002713#else /* CONFIG_NUMA */
2714
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002715static void set_zonelist_order(void)
2716{
2717 current_zonelist_order = ZONELIST_ORDER_ZONE;
2718}
2719
2720static void build_zonelists(pg_data_t *pgdat)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002721{
Christoph Lameter19655d32006-09-25 23:31:19 -07002722 int node, local_node;
Mel Gorman54a6eb52008-04-28 02:12:16 -07002723 enum zone_type j;
2724 struct zonelist *zonelist;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002725
2726 local_node = pgdat->node_id;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002727
Mel Gorman54a6eb52008-04-28 02:12:16 -07002728 zonelist = &pgdat->node_zonelists[0];
2729 j = build_zonelists_node(pgdat, zonelist, 0, MAX_NR_ZONES - 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002730
Mel Gorman54a6eb52008-04-28 02:12:16 -07002731 /*
2732 * Now we build the zonelist so that it contains the zones
2733 * of all the other nodes.
2734 * We don't want to pressure a particular node, so when
2735 * building the zones for node N, we make sure that the
2736 * zones coming right after the local ones are those from
2737 * node N+1 (modulo N)
2738 */
2739 for (node = local_node + 1; node < MAX_NUMNODES; node++) {
2740 if (!node_online(node))
2741 continue;
2742 j = build_zonelists_node(NODE_DATA(node), zonelist, j,
2743 MAX_NR_ZONES - 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002744 }
Mel Gorman54a6eb52008-04-28 02:12:16 -07002745 for (node = 0; node < local_node; node++) {
2746 if (!node_online(node))
2747 continue;
2748 j = build_zonelists_node(NODE_DATA(node), zonelist, j,
2749 MAX_NR_ZONES - 1);
2750 }
2751
Mel Gormandd1a2392008-04-28 02:12:17 -07002752 zonelist->_zonerefs[j].zone = NULL;
2753 zonelist->_zonerefs[j].zone_idx = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002754}
2755
Paul Jackson9276b1bc2006-12-06 20:31:48 -08002756/* non-NUMA variant of zonelist performance cache - just NULL zlcache_ptr */
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002757static void build_zonelist_cache(pg_data_t *pgdat)
Paul Jackson9276b1bc2006-12-06 20:31:48 -08002758{
Mel Gorman54a6eb52008-04-28 02:12:16 -07002759 pgdat->node_zonelists[0].zlcache_ptr = NULL;
Paul Jackson9276b1bc2006-12-06 20:31:48 -08002760}
2761
Linus Torvalds1da177e2005-04-16 15:20:36 -07002762#endif /* CONFIG_NUMA */
2763
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09002764/*
2765 * Boot pageset table. One per cpu which is going to be used for all
2766 * zones and all nodes. The parameters will be set in such a way
2767 * that an item put on a list will immediately be handed over to
2768 * the buddy list. This is safe since pageset manipulation is done
2769 * with interrupts disabled.
2770 *
2771 * The boot_pagesets must be kept even after bootup is complete for
2772 * unused processors and/or zones. They do play a role for bootstrapping
2773 * hotplugged processors.
2774 *
2775 * zoneinfo_show() and maybe other functions do
2776 * not check if the processor is online before following the pageset pointer.
2777 * Other parts of the kernel may not check if the zone is available.
2778 */
2779static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch);
2780static DEFINE_PER_CPU(struct per_cpu_pageset, boot_pageset);
2781
Rusty Russell9b1a4d32008-07-28 12:16:30 -05002782/* return values int ....just for stop_machine() */
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002783static int __build_all_zonelists(void *dummy)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002784{
Yasunori Goto68113782006-06-23 02:03:11 -07002785 int nid;
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09002786 int cpu;
Paul Jackson9276b1bc2006-12-06 20:31:48 -08002787
Bo Liu7f9cfb32009-08-18 14:11:19 -07002788#ifdef CONFIG_NUMA
2789 memset(node_load, 0, sizeof(node_load));
2790#endif
Paul Jackson9276b1bc2006-12-06 20:31:48 -08002791 for_each_online_node(nid) {
Christoph Lameter7ea15302007-10-16 01:25:29 -07002792 pg_data_t *pgdat = NODE_DATA(nid);
2793
2794 build_zonelists(pgdat);
2795 build_zonelist_cache(pgdat);
Paul Jackson9276b1bc2006-12-06 20:31:48 -08002796 }
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09002797
2798 /*
2799 * Initialize the boot_pagesets that are going to be used
2800 * for bootstrapping processors. The real pagesets for
2801 * each zone will be allocated later when the per cpu
2802 * allocator is available.
2803 *
2804 * boot_pagesets are used also for bootstrapping offline
2805 * cpus if the system is already booted because the pagesets
2806 * are needed to initialize allocators on a specific cpu too.
2807 * F.e. the percpu allocator needs the page allocator which
2808 * needs the percpu allocator in order to allocate its pagesets
2809 * (a chicken-egg dilemma).
2810 */
2811 for_each_possible_cpu(cpu)
2812 setup_pageset(&per_cpu(boot_pageset, cpu), 0);
2813
Yasunori Goto68113782006-06-23 02:03:11 -07002814 return 0;
2815}
Linus Torvalds1da177e2005-04-16 15:20:36 -07002816
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002817void build_all_zonelists(void)
Yasunori Goto68113782006-06-23 02:03:11 -07002818{
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002819 set_zonelist_order();
2820
Yasunori Goto68113782006-06-23 02:03:11 -07002821 if (system_state == SYSTEM_BOOTING) {
Randy Dunlap423b41d2006-09-27 01:50:12 -07002822 __build_all_zonelists(NULL);
Mel Gorman68ad8df2008-07-23 21:26:52 -07002823 mminit_verify_zonelist();
Yasunori Goto68113782006-06-23 02:03:11 -07002824 cpuset_init_current_mems_allowed();
2825 } else {
Simon Arlott183ff222007-10-20 01:27:18 +02002826 /* we have to stop all cpus to guarantee there is no user
Yasunori Goto68113782006-06-23 02:03:11 -07002827 of zonelist */
Rusty Russell9b1a4d32008-07-28 12:16:30 -05002828 stop_machine(__build_all_zonelists, NULL, NULL);
Yasunori Goto68113782006-06-23 02:03:11 -07002829 /* cpuset refresh routine should be here */
2830 }
Andrew Mortonbd1e22b2006-06-23 02:03:47 -07002831 vm_total_pages = nr_free_pagecache_pages();
Mel Gorman9ef9acb2007-10-16 01:25:54 -07002832 /*
2833 * Disable grouping by mobility if the number of pages in the
2834 * system is too low to allow the mechanism to work. It would be
2835 * more accurate, but expensive to check per-zone. This check is
2836 * made on memory-hotadd so a system can start with mobility
2837 * disabled and enable it later
2838 */
Mel Gormand9c23402007-10-16 01:26:01 -07002839 if (vm_total_pages < (pageblock_nr_pages * MIGRATE_TYPES))
Mel Gorman9ef9acb2007-10-16 01:25:54 -07002840 page_group_by_mobility_disabled = 1;
2841 else
2842 page_group_by_mobility_disabled = 0;
2843
2844 printk("Built %i zonelists in %s order, mobility grouping %s. "
2845 "Total pages: %ld\n",
Christoph Lameter62bc62a2009-06-16 15:32:15 -07002846 nr_online_nodes,
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002847 zonelist_order_name[current_zonelist_order],
Mel Gorman9ef9acb2007-10-16 01:25:54 -07002848 page_group_by_mobility_disabled ? "off" : "on",
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002849 vm_total_pages);
2850#ifdef CONFIG_NUMA
2851 printk("Policy zone: %s\n", zone_names[policy_zone]);
2852#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07002853}
2854
2855/*
2856 * Helper functions to size the waitqueue hash table.
2857 * Essentially these want to choose hash table sizes sufficiently
2858 * large so that collisions trying to wait on pages are rare.
2859 * But in fact, the number of active page waitqueues on typical
2860 * systems is ridiculously low, less than 200. So this is even
2861 * conservative, even though it seems large.
2862 *
2863 * The constant PAGES_PER_WAITQUEUE specifies the ratio of pages to
2864 * waitqueues, i.e. the size of the waitq table given the number of pages.
2865 */
2866#define PAGES_PER_WAITQUEUE 256
2867
Yasunori Gotocca448f2006-06-23 02:03:10 -07002868#ifndef CONFIG_MEMORY_HOTPLUG
Yasunori Goto02b694d2006-06-23 02:03:08 -07002869static inline unsigned long wait_table_hash_nr_entries(unsigned long pages)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002870{
2871 unsigned long size = 1;
2872
2873 pages /= PAGES_PER_WAITQUEUE;
2874
2875 while (size < pages)
2876 size <<= 1;
2877
2878 /*
2879 * Once we have dozens or even hundreds of threads sleeping
2880 * on IO we've got bigger problems than wait queue collision.
2881 * Limit the size of the wait table to a reasonable size.
2882 */
2883 size = min(size, 4096UL);
2884
2885 return max(size, 4UL);
2886}
Yasunori Gotocca448f2006-06-23 02:03:10 -07002887#else
2888/*
2889 * A zone's size might be changed by hot-add, so it is not possible to determine
2890 * a suitable size for its wait_table. So we use the maximum size now.
2891 *
2892 * The max wait table size = 4096 x sizeof(wait_queue_head_t). ie:
2893 *
2894 * i386 (preemption config) : 4096 x 16 = 64Kbyte.
2895 * ia64, x86-64 (no preemption): 4096 x 20 = 80Kbyte.
2896 * ia64, x86-64 (preemption) : 4096 x 24 = 96Kbyte.
2897 *
2898 * The maximum entries are prepared when a zone's memory is (512K + 256) pages
2899 * or more by the traditional way. (See above). It equals:
2900 *
2901 * i386, x86-64, powerpc(4K page size) : = ( 2G + 1M)byte.
2902 * ia64(16K page size) : = ( 8G + 4M)byte.
2903 * powerpc (64K page size) : = (32G +16M)byte.
2904 */
2905static inline unsigned long wait_table_hash_nr_entries(unsigned long pages)
2906{
2907 return 4096UL;
2908}
2909#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07002910
2911/*
2912 * This is an integer logarithm so that shifts can be used later
2913 * to extract the more random high bits from the multiplicative
2914 * hash function before the remainder is taken.
2915 */
2916static inline unsigned long wait_table_bits(unsigned long size)
2917{
2918 return ffz(~size);
2919}
2920
2921#define LONG_ALIGN(x) (((x)+(sizeof(long))-1)&~((sizeof(long))-1))
2922
Mel Gorman56fd56b2007-10-16 01:25:58 -07002923/*
Mel Gormand9c23402007-10-16 01:26:01 -07002924 * Mark a number of pageblocks as MIGRATE_RESERVE. The number
Mel Gorman41858962009-06-16 15:32:12 -07002925 * of blocks reserved is based on min_wmark_pages(zone). The memory within
2926 * the reserve will tend to store contiguous free pages. Setting min_free_kbytes
Mel Gorman56fd56b2007-10-16 01:25:58 -07002927 * higher will lead to a bigger reserve which will get freed as contiguous
2928 * blocks as reclaim kicks in
2929 */
2930static void setup_zone_migrate_reserve(struct zone *zone)
2931{
2932 unsigned long start_pfn, pfn, end_pfn;
2933 struct page *page;
Mel Gorman78986a62009-09-21 17:03:02 -07002934 unsigned long block_migratetype;
2935 int reserve;
Mel Gorman56fd56b2007-10-16 01:25:58 -07002936
2937 /* Get the start pfn, end pfn and the number of blocks to reserve */
2938 start_pfn = zone->zone_start_pfn;
2939 end_pfn = start_pfn + zone->spanned_pages;
Mel Gorman41858962009-06-16 15:32:12 -07002940 reserve = roundup(min_wmark_pages(zone), pageblock_nr_pages) >>
Mel Gormand9c23402007-10-16 01:26:01 -07002941 pageblock_order;
Mel Gorman56fd56b2007-10-16 01:25:58 -07002942
Mel Gorman78986a62009-09-21 17:03:02 -07002943 /*
2944 * Reserve blocks are generally in place to help high-order atomic
2945 * allocations that are short-lived. A min_free_kbytes value that
2946 * would result in more than 2 reserve blocks for atomic allocations
2947 * is assumed to be in place to help anti-fragmentation for the
2948 * future allocation of hugepages at runtime.
2949 */
2950 reserve = min(2, reserve);
2951
Mel Gormand9c23402007-10-16 01:26:01 -07002952 for (pfn = start_pfn; pfn < end_pfn; pfn += pageblock_nr_pages) {
Mel Gorman56fd56b2007-10-16 01:25:58 -07002953 if (!pfn_valid(pfn))
2954 continue;
2955 page = pfn_to_page(pfn);
2956
Adam Litke344c7902008-09-02 14:35:38 -07002957 /* Watch out for overlapping nodes */
2958 if (page_to_nid(page) != zone_to_nid(zone))
2959 continue;
2960
Mel Gorman56fd56b2007-10-16 01:25:58 -07002961 /* Blocks with reserved pages will never free, skip them. */
2962 if (PageReserved(page))
2963 continue;
2964
2965 block_migratetype = get_pageblock_migratetype(page);
2966
2967 /* If this block is reserved, account for it */
2968 if (reserve > 0 && block_migratetype == MIGRATE_RESERVE) {
2969 reserve--;
2970 continue;
2971 }
2972
2973 /* Suitable for reserving if this block is movable */
2974 if (reserve > 0 && block_migratetype == MIGRATE_MOVABLE) {
2975 set_pageblock_migratetype(page, MIGRATE_RESERVE);
2976 move_freepages_block(zone, page, MIGRATE_RESERVE);
2977 reserve--;
2978 continue;
2979 }
2980
2981 /*
2982 * If the reserve is met and this is a previous reserved block,
2983 * take it back
2984 */
2985 if (block_migratetype == MIGRATE_RESERVE) {
2986 set_pageblock_migratetype(page, MIGRATE_MOVABLE);
2987 move_freepages_block(zone, page, MIGRATE_MOVABLE);
2988 }
2989 }
2990}
Mel Gormanac0e5b72007-10-16 01:25:58 -07002991
Linus Torvalds1da177e2005-04-16 15:20:36 -07002992/*
2993 * Initially all pages are reserved - free ones are freed
2994 * up by free_all_bootmem() once the early boot process is
2995 * done. Non-atomic initialization, single-pass.
2996 */
Matt Tolentinoc09b4242006-01-17 07:03:44 +01002997void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone,
Dave Hansena2f3aa022007-01-10 23:15:30 -08002998 unsigned long start_pfn, enum memmap_context context)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002999{
Linus Torvalds1da177e2005-04-16 15:20:36 -07003000 struct page *page;
Andy Whitcroft29751f62005-06-23 00:08:00 -07003001 unsigned long end_pfn = start_pfn + size;
3002 unsigned long pfn;
KAMEZAWA Hiroyuki86051ca2008-04-29 00:58:21 -07003003 struct zone *z;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003004
Hugh Dickins22b31ee2009-01-06 14:40:09 -08003005 if (highest_memmap_pfn < end_pfn - 1)
3006 highest_memmap_pfn = end_pfn - 1;
3007
KAMEZAWA Hiroyuki86051ca2008-04-29 00:58:21 -07003008 z = &NODE_DATA(nid)->node_zones[zone];
Greg Ungerercbe8dd42006-01-12 01:05:24 -08003009 for (pfn = start_pfn; pfn < end_pfn; pfn++) {
Dave Hansena2f3aa022007-01-10 23:15:30 -08003010 /*
3011 * There can be holes in boot-time mem_map[]s
3012 * handed to this function. They do not
3013 * exist on hotplugged memory.
3014 */
3015 if (context == MEMMAP_EARLY) {
3016 if (!early_pfn_valid(pfn))
3017 continue;
3018 if (!early_pfn_in_nid(pfn, nid))
3019 continue;
3020 }
Andy Whitcroftd41dee32005-06-23 00:07:54 -07003021 page = pfn_to_page(pfn);
3022 set_page_links(page, zone, nid, pfn);
Mel Gorman708614e2008-07-23 21:26:51 -07003023 mminit_verify_page_links(page, zone, nid, pfn);
Nick Piggin7835e982006-03-22 00:08:40 -08003024 init_page_count(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003025 reset_page_mapcount(page);
3026 SetPageReserved(page);
Mel Gormanb2a0ac82007-10-16 01:25:48 -07003027 /*
3028 * Mark the block movable so that blocks are reserved for
3029 * movable at startup. This will force kernel allocations
3030 * to reserve their blocks rather than leaking throughout
3031 * the address space during boot when many long-lived
Mel Gorman56fd56b2007-10-16 01:25:58 -07003032 * kernel allocations are made. Later some blocks near
3033 * the start are marked MIGRATE_RESERVE by
3034 * setup_zone_migrate_reserve()
KAMEZAWA Hiroyuki86051ca2008-04-29 00:58:21 -07003035 *
3036 * bitmap is created for zone's valid pfn range. but memmap
3037 * can be created for invalid pages (for alignment)
3038 * check here not to call set_pageblock_migratetype() against
3039 * pfn out of zone.
Mel Gormanb2a0ac82007-10-16 01:25:48 -07003040 */
KAMEZAWA Hiroyuki86051ca2008-04-29 00:58:21 -07003041 if ((z->zone_start_pfn <= pfn)
3042 && (pfn < z->zone_start_pfn + z->spanned_pages)
3043 && !(pfn & (pageblock_nr_pages - 1)))
Mel Gorman56fd56b2007-10-16 01:25:58 -07003044 set_pageblock_migratetype(page, MIGRATE_MOVABLE);
Mel Gormanb2a0ac82007-10-16 01:25:48 -07003045
Linus Torvalds1da177e2005-04-16 15:20:36 -07003046 INIT_LIST_HEAD(&page->lru);
3047#ifdef WANT_PAGE_VIRTUAL
3048 /* The shift won't overflow because ZONE_NORMAL is below 4G. */
3049 if (!is_highmem_idx(zone))
Bob Picco3212c6b2005-06-27 14:36:28 -07003050 set_page_address(page, __va(pfn << PAGE_SHIFT));
Linus Torvalds1da177e2005-04-16 15:20:36 -07003051#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07003052 }
3053}
3054
Andi Kleen1e548de2008-02-04 22:29:26 -08003055static void __meminit zone_init_free_lists(struct zone *zone)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003056{
Mel Gormanb2a0ac82007-10-16 01:25:48 -07003057 int order, t;
3058 for_each_migratetype_order(order, t) {
3059 INIT_LIST_HEAD(&zone->free_area[order].free_list[t]);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003060 zone->free_area[order].nr_free = 0;
3061 }
3062}
3063
3064#ifndef __HAVE_ARCH_MEMMAP_INIT
3065#define memmap_init(size, nid, zone, start_pfn) \
Dave Hansena2f3aa022007-01-10 23:15:30 -08003066 memmap_init_zone((size), (nid), (zone), (start_pfn), MEMMAP_EARLY)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003067#endif
3068
Sam Ravnborg1d6f4e62008-01-17 15:21:12 -08003069static int zone_batchsize(struct zone *zone)
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003070{
David Howells3a6be872009-05-06 16:03:03 -07003071#ifdef CONFIG_MMU
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003072 int batch;
3073
3074 /*
3075 * The per-cpu-pages pools are set to around 1000th of the
Seth, Rohitba56e912005-10-29 18:15:47 -07003076 * size of the zone. But no more than 1/2 of a meg.
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003077 *
3078 * OK, so we don't know how big the cache is. So guess.
3079 */
3080 batch = zone->present_pages / 1024;
Seth, Rohitba56e912005-10-29 18:15:47 -07003081 if (batch * PAGE_SIZE > 512 * 1024)
3082 batch = (512 * 1024) / PAGE_SIZE;
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003083 batch /= 4; /* We effectively *= 4 below */
3084 if (batch < 1)
3085 batch = 1;
3086
3087 /*
Nick Piggin0ceaacc2005-12-04 13:55:25 +11003088 * Clamp the batch to a 2^n - 1 value. Having a power
3089 * of 2 value was found to be more likely to have
3090 * suboptimal cache aliasing properties in some cases.
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003091 *
Nick Piggin0ceaacc2005-12-04 13:55:25 +11003092 * For example if 2 tasks are alternately allocating
3093 * batches of pages, one task can end up with a lot
3094 * of pages of one half of the possible page colors
3095 * and the other with pages of the other colors.
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003096 */
David Howells91552032009-05-06 16:03:02 -07003097 batch = rounddown_pow_of_two(batch + batch/2) - 1;
Seth, Rohitba56e912005-10-29 18:15:47 -07003098
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003099 return batch;
David Howells3a6be872009-05-06 16:03:03 -07003100
3101#else
3102 /* The deferral and batching of frees should be suppressed under NOMMU
3103 * conditions.
3104 *
3105 * The problem is that NOMMU needs to be able to allocate large chunks
3106 * of contiguous memory as there's no hardware page translation to
3107 * assemble apparent contiguous memory from discontiguous pages.
3108 *
3109 * Queueing large contiguous runs of pages for batching, however,
3110 * causes the pages to actually be freed in smaller chunks. As there
3111 * can be a significant delay between the individual batches being
3112 * recycled, this leads to the once large chunks of space being
3113 * fragmented and becoming unavailable for high-order allocations.
3114 */
3115 return 0;
3116#endif
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003117}
3118
Adrian Bunkb69a7282008-07-23 21:28:12 -07003119static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch)
Christoph Lameter2caaad42005-06-21 17:15:00 -07003120{
3121 struct per_cpu_pages *pcp;
Mel Gorman5f8dcc22009-09-21 17:03:19 -07003122 int migratetype;
Christoph Lameter2caaad42005-06-21 17:15:00 -07003123
Magnus Damm1c6fe942005-10-26 01:58:59 -07003124 memset(p, 0, sizeof(*p));
3125
Christoph Lameter3dfa5722008-02-04 22:29:19 -08003126 pcp = &p->pcp;
Christoph Lameter2caaad42005-06-21 17:15:00 -07003127 pcp->count = 0;
Christoph Lameter2caaad42005-06-21 17:15:00 -07003128 pcp->high = 6 * batch;
3129 pcp->batch = max(1UL, 1 * batch);
Mel Gorman5f8dcc22009-09-21 17:03:19 -07003130 for (migratetype = 0; migratetype < MIGRATE_PCPTYPES; migratetype++)
3131 INIT_LIST_HEAD(&pcp->lists[migratetype]);
Christoph Lameter2caaad42005-06-21 17:15:00 -07003132}
3133
Rohit Seth8ad4b1f2006-01-08 01:00:40 -08003134/*
3135 * setup_pagelist_highmark() sets the high water mark for hot per_cpu_pagelist
3136 * to the value high for the pageset p.
3137 */
3138
3139static void setup_pagelist_highmark(struct per_cpu_pageset *p,
3140 unsigned long high)
3141{
3142 struct per_cpu_pages *pcp;
3143
Christoph Lameter3dfa5722008-02-04 22:29:19 -08003144 pcp = &p->pcp;
Rohit Seth8ad4b1f2006-01-08 01:00:40 -08003145 pcp->high = high;
3146 pcp->batch = max(1UL, high/4);
3147 if ((high/4) > (PAGE_SHIFT * 8))
3148 pcp->batch = PAGE_SHIFT * 8;
3149}
3150
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003151/*
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09003152 * Allocate per cpu pagesets and initialize them.
3153 * Before this call only boot pagesets were available.
3154 * Boot pagesets will no longer be used by this processorr
3155 * after setup_per_cpu_pageset().
Christoph Lameter2caaad42005-06-21 17:15:00 -07003156 */
Al Viro78d99552005-12-15 09:18:25 +00003157void __init setup_per_cpu_pageset(void)
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003158{
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09003159 struct zone *zone;
3160 int cpu;
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003161
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09003162 for_each_populated_zone(zone) {
3163 zone->pageset = alloc_percpu(struct per_cpu_pageset);
3164
3165 for_each_possible_cpu(cpu) {
3166 struct per_cpu_pageset *pcp = per_cpu_ptr(zone->pageset, cpu);
3167
3168 setup_pageset(pcp, zone_batchsize(zone));
3169
3170 if (percpu_pagelist_fraction)
3171 setup_pagelist_highmark(pcp,
3172 (zone->present_pages /
3173 percpu_pagelist_fraction));
3174 }
3175 }
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003176}
3177
Sam Ravnborg577a32f2007-05-17 23:29:25 +02003178static noinline __init_refok
Yasunori Gotocca448f2006-06-23 02:03:10 -07003179int zone_wait_table_init(struct zone *zone, unsigned long zone_size_pages)
Dave Hansened8ece22005-10-29 18:16:50 -07003180{
3181 int i;
3182 struct pglist_data *pgdat = zone->zone_pgdat;
Yasunori Gotocca448f2006-06-23 02:03:10 -07003183 size_t alloc_size;
Dave Hansened8ece22005-10-29 18:16:50 -07003184
3185 /*
3186 * The per-page waitqueue mechanism uses hashed waitqueues
3187 * per zone.
3188 */
Yasunori Goto02b694d2006-06-23 02:03:08 -07003189 zone->wait_table_hash_nr_entries =
3190 wait_table_hash_nr_entries(zone_size_pages);
3191 zone->wait_table_bits =
3192 wait_table_bits(zone->wait_table_hash_nr_entries);
Yasunori Gotocca448f2006-06-23 02:03:10 -07003193 alloc_size = zone->wait_table_hash_nr_entries
3194 * sizeof(wait_queue_head_t);
3195
Heiko Carstenscd94b9d2008-05-23 13:04:52 -07003196 if (!slab_is_available()) {
Yasunori Gotocca448f2006-06-23 02:03:10 -07003197 zone->wait_table = (wait_queue_head_t *)
3198 alloc_bootmem_node(pgdat, alloc_size);
3199 } else {
3200 /*
3201 * This case means that a zone whose size was 0 gets new memory
3202 * via memory hot-add.
3203 * But it may be the case that a new node was hot-added. In
3204 * this case vmalloc() will not be able to use this new node's
3205 * memory - this wait_table must be initialized to use this new
3206 * node itself as well.
3207 * To use this new node's memory, further consideration will be
3208 * necessary.
3209 */
Jesper Juhl8691f3a2007-10-16 01:24:49 -07003210 zone->wait_table = vmalloc(alloc_size);
Yasunori Gotocca448f2006-06-23 02:03:10 -07003211 }
3212 if (!zone->wait_table)
3213 return -ENOMEM;
Dave Hansened8ece22005-10-29 18:16:50 -07003214
Yasunori Goto02b694d2006-06-23 02:03:08 -07003215 for(i = 0; i < zone->wait_table_hash_nr_entries; ++i)
Dave Hansened8ece22005-10-29 18:16:50 -07003216 init_waitqueue_head(zone->wait_table + i);
Yasunori Gotocca448f2006-06-23 02:03:10 -07003217
3218 return 0;
Dave Hansened8ece22005-10-29 18:16:50 -07003219}
3220
Shaohua Li112067f2009-09-21 17:01:16 -07003221static int __zone_pcp_update(void *data)
3222{
3223 struct zone *zone = data;
3224 int cpu;
3225 unsigned long batch = zone_batchsize(zone), flags;
3226
3227 for (cpu = 0; cpu < NR_CPUS; cpu++) {
3228 struct per_cpu_pageset *pset;
3229 struct per_cpu_pages *pcp;
3230
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09003231 pset = per_cpu_ptr(zone->pageset, cpu);
Shaohua Li112067f2009-09-21 17:01:16 -07003232 pcp = &pset->pcp;
3233
3234 local_irq_save(flags);
Mel Gorman5f8dcc22009-09-21 17:03:19 -07003235 free_pcppages_bulk(zone, pcp->count, pcp);
Shaohua Li112067f2009-09-21 17:01:16 -07003236 setup_pageset(pset, batch);
3237 local_irq_restore(flags);
3238 }
3239 return 0;
3240}
3241
3242void zone_pcp_update(struct zone *zone)
3243{
3244 stop_machine(__zone_pcp_update, zone, NULL);
3245}
3246
Matt Tolentinoc09b4242006-01-17 07:03:44 +01003247static __meminit void zone_pcp_init(struct zone *zone)
Dave Hansened8ece22005-10-29 18:16:50 -07003248{
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09003249 /*
3250 * per cpu subsystem is not up at this point. The following code
3251 * relies on the ability of the linker to provide the
3252 * offset of a (static) per cpu variable into the per cpu area.
3253 */
3254 zone->pageset = &boot_pageset;
Dave Hansened8ece22005-10-29 18:16:50 -07003255
Anton Blanchardf5335c02006-03-25 03:06:49 -08003256 if (zone->present_pages)
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09003257 printk(KERN_DEBUG " %s zone: %lu pages, LIFO batch:%u\n",
3258 zone->name, zone->present_pages,
3259 zone_batchsize(zone));
Dave Hansened8ece22005-10-29 18:16:50 -07003260}
3261
Yasunori Goto718127c2006-06-23 02:03:10 -07003262__meminit int init_currently_empty_zone(struct zone *zone,
3263 unsigned long zone_start_pfn,
Dave Hansena2f3aa022007-01-10 23:15:30 -08003264 unsigned long size,
3265 enum memmap_context context)
Dave Hansened8ece22005-10-29 18:16:50 -07003266{
3267 struct pglist_data *pgdat = zone->zone_pgdat;
Yasunori Gotocca448f2006-06-23 02:03:10 -07003268 int ret;
3269 ret = zone_wait_table_init(zone, size);
3270 if (ret)
3271 return ret;
Dave Hansened8ece22005-10-29 18:16:50 -07003272 pgdat->nr_zones = zone_idx(zone) + 1;
3273
Dave Hansened8ece22005-10-29 18:16:50 -07003274 zone->zone_start_pfn = zone_start_pfn;
3275
Mel Gorman708614e2008-07-23 21:26:51 -07003276 mminit_dprintk(MMINIT_TRACE, "memmap_init",
3277 "Initialising map node %d zone %lu pfns %lu -> %lu\n",
3278 pgdat->node_id,
3279 (unsigned long)zone_idx(zone),
3280 zone_start_pfn, (zone_start_pfn + size));
3281
Andi Kleen1e548de2008-02-04 22:29:26 -08003282 zone_init_free_lists(zone);
Yasunori Goto718127c2006-06-23 02:03:10 -07003283
3284 return 0;
Dave Hansened8ece22005-10-29 18:16:50 -07003285}
3286
Mel Gormanc7132162006-09-27 01:49:43 -07003287#ifdef CONFIG_ARCH_POPULATES_NODE_MAP
3288/*
3289 * Basic iterator support. Return the first range of PFNs for a node
3290 * Note: nid == MAX_NUMNODES returns first region regardless of node
3291 */
Yasunori Gotoa3142c82007-05-08 00:23:07 -07003292static int __meminit first_active_region_index_in_nid(int nid)
Mel Gormanc7132162006-09-27 01:49:43 -07003293{
3294 int i;
3295
3296 for (i = 0; i < nr_nodemap_entries; i++)
3297 if (nid == MAX_NUMNODES || early_node_map[i].nid == nid)
3298 return i;
3299
3300 return -1;
3301}
3302
3303/*
3304 * Basic iterator support. Return the next active range of PFNs for a node
Simon Arlott183ff222007-10-20 01:27:18 +02003305 * Note: nid == MAX_NUMNODES returns next region regardless of node
Mel Gormanc7132162006-09-27 01:49:43 -07003306 */
Yasunori Gotoa3142c82007-05-08 00:23:07 -07003307static int __meminit next_active_region_index_in_nid(int index, int nid)
Mel Gormanc7132162006-09-27 01:49:43 -07003308{
3309 for (index = index + 1; index < nr_nodemap_entries; index++)
3310 if (nid == MAX_NUMNODES || early_node_map[index].nid == nid)
3311 return index;
3312
3313 return -1;
3314}
3315
3316#ifndef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
3317/*
3318 * Required by SPARSEMEM. Given a PFN, return what node the PFN is on.
3319 * Architectures may implement their own version but if add_active_range()
3320 * was used and there are no special requirements, this is a convenient
3321 * alternative
3322 */
KAMEZAWA Hiroyukif2dbcfa2009-02-18 14:48:32 -08003323int __meminit __early_pfn_to_nid(unsigned long pfn)
Mel Gormanc7132162006-09-27 01:49:43 -07003324{
3325 int i;
3326
3327 for (i = 0; i < nr_nodemap_entries; i++) {
3328 unsigned long start_pfn = early_node_map[i].start_pfn;
3329 unsigned long end_pfn = early_node_map[i].end_pfn;
3330
3331 if (start_pfn <= pfn && pfn < end_pfn)
3332 return early_node_map[i].nid;
3333 }
KAMEZAWA Hiroyukicc2559b2009-02-18 14:48:33 -08003334 /* This is a memory hole */
3335 return -1;
Mel Gormanc7132162006-09-27 01:49:43 -07003336}
3337#endif /* CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID */
3338
KAMEZAWA Hiroyukif2dbcfa2009-02-18 14:48:32 -08003339int __meminit early_pfn_to_nid(unsigned long pfn)
3340{
KAMEZAWA Hiroyukicc2559b2009-02-18 14:48:33 -08003341 int nid;
3342
3343 nid = __early_pfn_to_nid(pfn);
3344 if (nid >= 0)
3345 return nid;
3346 /* just returns 0 */
3347 return 0;
KAMEZAWA Hiroyukif2dbcfa2009-02-18 14:48:32 -08003348}
3349
KAMEZAWA Hiroyukicc2559b2009-02-18 14:48:33 -08003350#ifdef CONFIG_NODES_SPAN_OTHER_NODES
3351bool __meminit early_pfn_in_nid(unsigned long pfn, int node)
3352{
3353 int nid;
3354
3355 nid = __early_pfn_to_nid(pfn);
3356 if (nid >= 0 && nid != node)
3357 return false;
3358 return true;
3359}
3360#endif
KAMEZAWA Hiroyukif2dbcfa2009-02-18 14:48:32 -08003361
Mel Gormanc7132162006-09-27 01:49:43 -07003362/* Basic iterator support to walk early_node_map[] */
3363#define for_each_active_range_index_in_nid(i, nid) \
3364 for (i = first_active_region_index_in_nid(nid); i != -1; \
3365 i = next_active_region_index_in_nid(i, nid))
3366
3367/**
3368 * free_bootmem_with_active_regions - Call free_bootmem_node for each active range
Randy Dunlap88ca3b92006-10-04 02:15:25 -07003369 * @nid: The node to free memory on. If MAX_NUMNODES, all nodes are freed.
3370 * @max_low_pfn: The highest PFN that will be passed to free_bootmem_node
Mel Gormanc7132162006-09-27 01:49:43 -07003371 *
3372 * If an architecture guarantees that all ranges registered with
3373 * add_active_ranges() contain no holes and may be freed, this
3374 * this function may be used instead of calling free_bootmem() manually.
3375 */
3376void __init free_bootmem_with_active_regions(int nid,
3377 unsigned long max_low_pfn)
3378{
3379 int i;
3380
3381 for_each_active_range_index_in_nid(i, nid) {
3382 unsigned long size_pages = 0;
3383 unsigned long end_pfn = early_node_map[i].end_pfn;
3384
3385 if (early_node_map[i].start_pfn >= max_low_pfn)
3386 continue;
3387
3388 if (end_pfn > max_low_pfn)
3389 end_pfn = max_low_pfn;
3390
3391 size_pages = end_pfn - early_node_map[i].start_pfn;
3392 free_bootmem_node(NODE_DATA(early_node_map[i].nid),
3393 PFN_PHYS(early_node_map[i].start_pfn),
3394 size_pages << PAGE_SHIFT);
3395 }
3396}
3397
Yinghai Lu08677212010-02-10 01:20:20 -08003398int __init add_from_early_node_map(struct range *range, int az,
3399 int nr_range, int nid)
3400{
3401 int i;
3402 u64 start, end;
3403
3404 /* need to go over early_node_map to find out good range for node */
3405 for_each_active_range_index_in_nid(i, nid) {
3406 start = early_node_map[i].start_pfn;
3407 end = early_node_map[i].end_pfn;
3408 nr_range = add_range(range, az, nr_range, start, end);
3409 }
3410 return nr_range;
3411}
3412
Yinghai Lu2ee78f72010-02-17 11:29:49 -08003413#ifdef CONFIG_NO_BOOTMEM
Yinghai Lu08677212010-02-10 01:20:20 -08003414void * __init __alloc_memory_core_early(int nid, u64 size, u64 align,
3415 u64 goal, u64 limit)
3416{
3417 int i;
3418 void *ptr;
3419
3420 /* need to go over early_node_map to find out good range for node */
3421 for_each_active_range_index_in_nid(i, nid) {
3422 u64 addr;
3423 u64 ei_start, ei_last;
3424
3425 ei_last = early_node_map[i].end_pfn;
3426 ei_last <<= PAGE_SHIFT;
3427 ei_start = early_node_map[i].start_pfn;
3428 ei_start <<= PAGE_SHIFT;
3429 addr = find_early_area(ei_start, ei_last,
3430 goal, limit, size, align);
3431
3432 if (addr == -1ULL)
3433 continue;
3434
3435#if 0
3436 printk(KERN_DEBUG "alloc (nid=%d %llx - %llx) (%llx - %llx) %llx %llx => %llx\n",
3437 nid,
3438 ei_start, ei_last, goal, limit, size,
3439 align, addr);
3440#endif
3441
3442 ptr = phys_to_virt(addr);
3443 memset(ptr, 0, size);
3444 reserve_early_without_check(addr, addr + size, "BOOTMEM");
3445 return ptr;
3446 }
3447
3448 return NULL;
3449}
Yinghai Lu2ee78f72010-02-17 11:29:49 -08003450#endif
Yinghai Lu08677212010-02-10 01:20:20 -08003451
3452
Yinghai Lub5bc6c02008-06-14 18:32:52 -07003453void __init work_with_active_regions(int nid, work_fn_t work_fn, void *data)
3454{
3455 int i;
Yinghai Lud52d53b2008-06-16 20:10:55 -07003456 int ret;
Yinghai Lub5bc6c02008-06-14 18:32:52 -07003457
Yinghai Lud52d53b2008-06-16 20:10:55 -07003458 for_each_active_range_index_in_nid(i, nid) {
3459 ret = work_fn(early_node_map[i].start_pfn,
3460 early_node_map[i].end_pfn, data);
3461 if (ret)
3462 break;
3463 }
Yinghai Lub5bc6c02008-06-14 18:32:52 -07003464}
Mel Gormanc7132162006-09-27 01:49:43 -07003465/**
3466 * sparse_memory_present_with_active_regions - Call memory_present for each active range
Randy Dunlap88ca3b92006-10-04 02:15:25 -07003467 * @nid: The node to call memory_present for. If MAX_NUMNODES, all nodes will be used.
Mel Gormanc7132162006-09-27 01:49:43 -07003468 *
3469 * If an architecture guarantees that all ranges registered with
3470 * add_active_ranges() contain no holes and may be freed, this
Randy Dunlap88ca3b92006-10-04 02:15:25 -07003471 * function may be used instead of calling memory_present() manually.
Mel Gormanc7132162006-09-27 01:49:43 -07003472 */
3473void __init sparse_memory_present_with_active_regions(int nid)
3474{
3475 int i;
3476
3477 for_each_active_range_index_in_nid(i, nid)
3478 memory_present(early_node_map[i].nid,
3479 early_node_map[i].start_pfn,
3480 early_node_map[i].end_pfn);
3481}
3482
3483/**
3484 * get_pfn_range_for_nid - Return the start and end page frames for a node
Randy Dunlap88ca3b92006-10-04 02:15:25 -07003485 * @nid: The nid to return the range for. If MAX_NUMNODES, the min and max PFN are returned.
3486 * @start_pfn: Passed by reference. On return, it will have the node start_pfn.
3487 * @end_pfn: Passed by reference. On return, it will have the node end_pfn.
Mel Gormanc7132162006-09-27 01:49:43 -07003488 *
3489 * It returns the start and end page frame of a node based on information
3490 * provided by an arch calling add_active_range(). If called for a node
3491 * with no available memory, a warning is printed and the start and end
Randy Dunlap88ca3b92006-10-04 02:15:25 -07003492 * PFNs will be 0.
Mel Gormanc7132162006-09-27 01:49:43 -07003493 */
Yasunori Gotoa3142c82007-05-08 00:23:07 -07003494void __meminit get_pfn_range_for_nid(unsigned int nid,
Mel Gormanc7132162006-09-27 01:49:43 -07003495 unsigned long *start_pfn, unsigned long *end_pfn)
3496{
3497 int i;
3498 *start_pfn = -1UL;
3499 *end_pfn = 0;
3500
3501 for_each_active_range_index_in_nid(i, nid) {
3502 *start_pfn = min(*start_pfn, early_node_map[i].start_pfn);
3503 *end_pfn = max(*end_pfn, early_node_map[i].end_pfn);
3504 }
3505
Christoph Lameter633c0662007-10-16 01:25:37 -07003506 if (*start_pfn == -1UL)
Mel Gormanc7132162006-09-27 01:49:43 -07003507 *start_pfn = 0;
Mel Gormanc7132162006-09-27 01:49:43 -07003508}
3509
3510/*
Mel Gorman2a1e2742007-07-17 04:03:12 -07003511 * This finds a zone that can be used for ZONE_MOVABLE pages. The
3512 * assumption is made that zones within a node are ordered in monotonic
3513 * increasing memory addresses so that the "highest" populated zone is used
3514 */
Adrian Bunkb69a7282008-07-23 21:28:12 -07003515static void __init find_usable_zone_for_movable(void)
Mel Gorman2a1e2742007-07-17 04:03:12 -07003516{
3517 int zone_index;
3518 for (zone_index = MAX_NR_ZONES - 1; zone_index >= 0; zone_index--) {
3519 if (zone_index == ZONE_MOVABLE)
3520 continue;
3521
3522 if (arch_zone_highest_possible_pfn[zone_index] >
3523 arch_zone_lowest_possible_pfn[zone_index])
3524 break;
3525 }
3526
3527 VM_BUG_ON(zone_index == -1);
3528 movable_zone = zone_index;
3529}
3530
3531/*
3532 * The zone ranges provided by the architecture do not include ZONE_MOVABLE
3533 * because it is sized independant of architecture. Unlike the other zones,
3534 * the starting point for ZONE_MOVABLE is not fixed. It may be different
3535 * in each node depending on the size of each node and how evenly kernelcore
3536 * is distributed. This helper function adjusts the zone ranges
3537 * provided by the architecture for a given node by using the end of the
3538 * highest usable zone for ZONE_MOVABLE. This preserves the assumption that
3539 * zones within a node are in order of monotonic increases memory addresses
3540 */
Adrian Bunkb69a7282008-07-23 21:28:12 -07003541static void __meminit adjust_zone_range_for_zone_movable(int nid,
Mel Gorman2a1e2742007-07-17 04:03:12 -07003542 unsigned long zone_type,
3543 unsigned long node_start_pfn,
3544 unsigned long node_end_pfn,
3545 unsigned long *zone_start_pfn,
3546 unsigned long *zone_end_pfn)
3547{
3548 /* Only adjust if ZONE_MOVABLE is on this node */
3549 if (zone_movable_pfn[nid]) {
3550 /* Size ZONE_MOVABLE */
3551 if (zone_type == ZONE_MOVABLE) {
3552 *zone_start_pfn = zone_movable_pfn[nid];
3553 *zone_end_pfn = min(node_end_pfn,
3554 arch_zone_highest_possible_pfn[movable_zone]);
3555
3556 /* Adjust for ZONE_MOVABLE starting within this range */
3557 } else if (*zone_start_pfn < zone_movable_pfn[nid] &&
3558 *zone_end_pfn > zone_movable_pfn[nid]) {
3559 *zone_end_pfn = zone_movable_pfn[nid];
3560
3561 /* Check if this whole range is within ZONE_MOVABLE */
3562 } else if (*zone_start_pfn >= zone_movable_pfn[nid])
3563 *zone_start_pfn = *zone_end_pfn;
3564 }
3565}
3566
3567/*
Mel Gormanc7132162006-09-27 01:49:43 -07003568 * Return the number of pages a zone spans in a node, including holes
3569 * present_pages = zone_spanned_pages_in_node() - zone_absent_pages_in_node()
3570 */
Paul Mundt6ea6e682007-07-15 23:38:20 -07003571static unsigned long __meminit zone_spanned_pages_in_node(int nid,
Mel Gormanc7132162006-09-27 01:49:43 -07003572 unsigned long zone_type,
3573 unsigned long *ignored)
3574{
3575 unsigned long node_start_pfn, node_end_pfn;
3576 unsigned long zone_start_pfn, zone_end_pfn;
3577
3578 /* Get the start and end of the node and zone */
3579 get_pfn_range_for_nid(nid, &node_start_pfn, &node_end_pfn);
3580 zone_start_pfn = arch_zone_lowest_possible_pfn[zone_type];
3581 zone_end_pfn = arch_zone_highest_possible_pfn[zone_type];
Mel Gorman2a1e2742007-07-17 04:03:12 -07003582 adjust_zone_range_for_zone_movable(nid, zone_type,
3583 node_start_pfn, node_end_pfn,
3584 &zone_start_pfn, &zone_end_pfn);
Mel Gormanc7132162006-09-27 01:49:43 -07003585
3586 /* Check that this node has pages within the zone's required range */
3587 if (zone_end_pfn < node_start_pfn || zone_start_pfn > node_end_pfn)
3588 return 0;
3589
3590 /* Move the zone boundaries inside the node if necessary */
3591 zone_end_pfn = min(zone_end_pfn, node_end_pfn);
3592 zone_start_pfn = max(zone_start_pfn, node_start_pfn);
3593
3594 /* Return the spanned pages */
3595 return zone_end_pfn - zone_start_pfn;
3596}
3597
3598/*
3599 * Return the number of holes in a range on a node. If nid is MAX_NUMNODES,
Randy Dunlap88ca3b92006-10-04 02:15:25 -07003600 * then all holes in the requested range will be accounted for.
Mel Gormanc7132162006-09-27 01:49:43 -07003601 */
Yinghai Lu32996252009-12-15 17:59:02 -08003602unsigned long __meminit __absent_pages_in_range(int nid,
Mel Gormanc7132162006-09-27 01:49:43 -07003603 unsigned long range_start_pfn,
3604 unsigned long range_end_pfn)
3605{
3606 int i = 0;
3607 unsigned long prev_end_pfn = 0, hole_pages = 0;
3608 unsigned long start_pfn;
3609
3610 /* Find the end_pfn of the first active range of pfns in the node */
3611 i = first_active_region_index_in_nid(nid);
3612 if (i == -1)
3613 return 0;
3614
Mel Gormanb5445f92007-07-26 10:41:18 -07003615 prev_end_pfn = min(early_node_map[i].start_pfn, range_end_pfn);
3616
Mel Gorman9c7cd682006-09-27 01:49:58 -07003617 /* Account for ranges before physical memory on this node */
3618 if (early_node_map[i].start_pfn > range_start_pfn)
Mel Gormanb5445f92007-07-26 10:41:18 -07003619 hole_pages = prev_end_pfn - range_start_pfn;
Mel Gormanc7132162006-09-27 01:49:43 -07003620
3621 /* Find all holes for the zone within the node */
3622 for (; i != -1; i = next_active_region_index_in_nid(i, nid)) {
3623
3624 /* No need to continue if prev_end_pfn is outside the zone */
3625 if (prev_end_pfn >= range_end_pfn)
3626 break;
3627
3628 /* Make sure the end of the zone is not within the hole */
3629 start_pfn = min(early_node_map[i].start_pfn, range_end_pfn);
3630 prev_end_pfn = max(prev_end_pfn, range_start_pfn);
3631
3632 /* Update the hole size cound and move on */
3633 if (start_pfn > range_start_pfn) {
3634 BUG_ON(prev_end_pfn > start_pfn);
3635 hole_pages += start_pfn - prev_end_pfn;
3636 }
3637 prev_end_pfn = early_node_map[i].end_pfn;
3638 }
3639
Mel Gorman9c7cd682006-09-27 01:49:58 -07003640 /* Account for ranges past physical memory on this node */
3641 if (range_end_pfn > prev_end_pfn)
Mel Gorman0c6cb972006-10-28 10:38:59 -07003642 hole_pages += range_end_pfn -
Mel Gorman9c7cd682006-09-27 01:49:58 -07003643 max(range_start_pfn, prev_end_pfn);
3644
Mel Gormanc7132162006-09-27 01:49:43 -07003645 return hole_pages;
3646}
3647
3648/**
3649 * absent_pages_in_range - Return number of page frames in holes within a range
3650 * @start_pfn: The start PFN to start searching for holes
3651 * @end_pfn: The end PFN to stop searching for holes
3652 *
Randy Dunlap88ca3b92006-10-04 02:15:25 -07003653 * It returns the number of pages frames in memory holes within a range.
Mel Gormanc7132162006-09-27 01:49:43 -07003654 */
3655unsigned long __init absent_pages_in_range(unsigned long start_pfn,
3656 unsigned long end_pfn)
3657{
3658 return __absent_pages_in_range(MAX_NUMNODES, start_pfn, end_pfn);
3659}
3660
3661/* Return the number of page frames in holes in a zone on a node */
Paul Mundt6ea6e682007-07-15 23:38:20 -07003662static unsigned long __meminit zone_absent_pages_in_node(int nid,
Mel Gormanc7132162006-09-27 01:49:43 -07003663 unsigned long zone_type,
3664 unsigned long *ignored)
3665{
Mel Gorman9c7cd682006-09-27 01:49:58 -07003666 unsigned long node_start_pfn, node_end_pfn;
3667 unsigned long zone_start_pfn, zone_end_pfn;
3668
3669 get_pfn_range_for_nid(nid, &node_start_pfn, &node_end_pfn);
3670 zone_start_pfn = max(arch_zone_lowest_possible_pfn[zone_type],
3671 node_start_pfn);
3672 zone_end_pfn = min(arch_zone_highest_possible_pfn[zone_type],
3673 node_end_pfn);
3674
Mel Gorman2a1e2742007-07-17 04:03:12 -07003675 adjust_zone_range_for_zone_movable(nid, zone_type,
3676 node_start_pfn, node_end_pfn,
3677 &zone_start_pfn, &zone_end_pfn);
Mel Gorman9c7cd682006-09-27 01:49:58 -07003678 return __absent_pages_in_range(nid, zone_start_pfn, zone_end_pfn);
Mel Gormanc7132162006-09-27 01:49:43 -07003679}
Mel Gorman0e0b8642006-09-27 01:49:56 -07003680
Mel Gormanc7132162006-09-27 01:49:43 -07003681#else
Paul Mundt6ea6e682007-07-15 23:38:20 -07003682static inline unsigned long __meminit zone_spanned_pages_in_node(int nid,
Mel Gormanc7132162006-09-27 01:49:43 -07003683 unsigned long zone_type,
3684 unsigned long *zones_size)
3685{
3686 return zones_size[zone_type];
3687}
3688
Paul Mundt6ea6e682007-07-15 23:38:20 -07003689static inline unsigned long __meminit zone_absent_pages_in_node(int nid,
Mel Gormanc7132162006-09-27 01:49:43 -07003690 unsigned long zone_type,
3691 unsigned long *zholes_size)
3692{
3693 if (!zholes_size)
3694 return 0;
3695
3696 return zholes_size[zone_type];
3697}
Mel Gorman0e0b8642006-09-27 01:49:56 -07003698
Mel Gormanc7132162006-09-27 01:49:43 -07003699#endif
3700
Yasunori Gotoa3142c82007-05-08 00:23:07 -07003701static void __meminit calculate_node_totalpages(struct pglist_data *pgdat,
Mel Gormanc7132162006-09-27 01:49:43 -07003702 unsigned long *zones_size, unsigned long *zholes_size)
3703{
3704 unsigned long realtotalpages, totalpages = 0;
3705 enum zone_type i;
3706
3707 for (i = 0; i < MAX_NR_ZONES; i++)
3708 totalpages += zone_spanned_pages_in_node(pgdat->node_id, i,
3709 zones_size);
3710 pgdat->node_spanned_pages = totalpages;
3711
3712 realtotalpages = totalpages;
3713 for (i = 0; i < MAX_NR_ZONES; i++)
3714 realtotalpages -=
3715 zone_absent_pages_in_node(pgdat->node_id, i,
3716 zholes_size);
3717 pgdat->node_present_pages = realtotalpages;
3718 printk(KERN_DEBUG "On node %d totalpages: %lu\n", pgdat->node_id,
3719 realtotalpages);
3720}
3721
Mel Gorman835c1342007-10-16 01:25:47 -07003722#ifndef CONFIG_SPARSEMEM
3723/*
3724 * Calculate the size of the zone->blockflags rounded to an unsigned long
Mel Gormand9c23402007-10-16 01:26:01 -07003725 * Start by making sure zonesize is a multiple of pageblock_order by rounding
3726 * up. Then use 1 NR_PAGEBLOCK_BITS worth of bits per pageblock, finally
Mel Gorman835c1342007-10-16 01:25:47 -07003727 * round what is now in bits to nearest long in bits, then return it in
3728 * bytes.
3729 */
3730static unsigned long __init usemap_size(unsigned long zonesize)
3731{
3732 unsigned long usemapsize;
3733
Mel Gormand9c23402007-10-16 01:26:01 -07003734 usemapsize = roundup(zonesize, pageblock_nr_pages);
3735 usemapsize = usemapsize >> pageblock_order;
Mel Gorman835c1342007-10-16 01:25:47 -07003736 usemapsize *= NR_PAGEBLOCK_BITS;
3737 usemapsize = roundup(usemapsize, 8 * sizeof(unsigned long));
3738
3739 return usemapsize / 8;
3740}
3741
3742static void __init setup_usemap(struct pglist_data *pgdat,
3743 struct zone *zone, unsigned long zonesize)
3744{
3745 unsigned long usemapsize = usemap_size(zonesize);
3746 zone->pageblock_flags = NULL;
Julia Lawall58a01a42009-01-06 14:39:28 -08003747 if (usemapsize)
Mel Gorman835c1342007-10-16 01:25:47 -07003748 zone->pageblock_flags = alloc_bootmem_node(pgdat, usemapsize);
Mel Gorman835c1342007-10-16 01:25:47 -07003749}
3750#else
3751static void inline setup_usemap(struct pglist_data *pgdat,
3752 struct zone *zone, unsigned long zonesize) {}
3753#endif /* CONFIG_SPARSEMEM */
3754
Mel Gormand9c23402007-10-16 01:26:01 -07003755#ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
Mel Gormanba72cb82007-11-28 16:21:13 -08003756
3757/* Return a sensible default order for the pageblock size. */
3758static inline int pageblock_default_order(void)
3759{
3760 if (HPAGE_SHIFT > PAGE_SHIFT)
3761 return HUGETLB_PAGE_ORDER;
3762
3763 return MAX_ORDER-1;
3764}
3765
Mel Gormand9c23402007-10-16 01:26:01 -07003766/* Initialise the number of pages represented by NR_PAGEBLOCK_BITS */
3767static inline void __init set_pageblock_order(unsigned int order)
3768{
3769 /* Check that pageblock_nr_pages has not already been setup */
3770 if (pageblock_order)
3771 return;
3772
3773 /*
3774 * Assume the largest contiguous order of interest is a huge page.
3775 * This value may be variable depending on boot parameters on IA64
3776 */
3777 pageblock_order = order;
3778}
3779#else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
3780
Mel Gormanba72cb82007-11-28 16:21:13 -08003781/*
3782 * When CONFIG_HUGETLB_PAGE_SIZE_VARIABLE is not set, set_pageblock_order()
3783 * and pageblock_default_order() are unused as pageblock_order is set
3784 * at compile-time. See include/linux/pageblock-flags.h for the values of
3785 * pageblock_order based on the kernel config
3786 */
3787static inline int pageblock_default_order(unsigned int order)
3788{
3789 return MAX_ORDER-1;
3790}
Mel Gormand9c23402007-10-16 01:26:01 -07003791#define set_pageblock_order(x) do {} while (0)
3792
3793#endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
3794
Linus Torvalds1da177e2005-04-16 15:20:36 -07003795/*
3796 * Set up the zone data structures:
3797 * - mark all pages reserved
3798 * - mark all memory queues empty
3799 * - clear the memory bitmaps
3800 */
Alexander van Heukelumb5a0e012008-02-23 15:24:06 -08003801static void __paginginit free_area_init_core(struct pglist_data *pgdat,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003802 unsigned long *zones_size, unsigned long *zholes_size)
3803{
Christoph Lameter2f1b6242006-09-25 23:31:13 -07003804 enum zone_type j;
Dave Hansened8ece22005-10-29 18:16:50 -07003805 int nid = pgdat->node_id;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003806 unsigned long zone_start_pfn = pgdat->node_start_pfn;
Yasunori Goto718127c2006-06-23 02:03:10 -07003807 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003808
Dave Hansen208d54e2005-10-29 18:16:52 -07003809 pgdat_resize_init(pgdat);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003810 pgdat->nr_zones = 0;
3811 init_waitqueue_head(&pgdat->kswapd_wait);
3812 pgdat->kswapd_max_order = 0;
KAMEZAWA Hiroyuki52d4b9a2008-10-18 20:28:16 -07003813 pgdat_page_cgroup_init(pgdat);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003814
3815 for (j = 0; j < MAX_NR_ZONES; j++) {
3816 struct zone *zone = pgdat->node_zones + j;
Mel Gorman0e0b8642006-09-27 01:49:56 -07003817 unsigned long size, realsize, memmap_pages;
Christoph Lameterb69408e2008-10-18 20:26:14 -07003818 enum lru_list l;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003819
Mel Gormanc7132162006-09-27 01:49:43 -07003820 size = zone_spanned_pages_in_node(nid, j, zones_size);
3821 realsize = size - zone_absent_pages_in_node(nid, j,
3822 zholes_size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003823
Mel Gorman0e0b8642006-09-27 01:49:56 -07003824 /*
3825 * Adjust realsize so that it accounts for how much memory
3826 * is used by this zone for memmap. This affects the watermark
3827 * and per-cpu initialisations
3828 */
Johannes Weinerf7232152008-05-23 13:04:21 -07003829 memmap_pages =
3830 PAGE_ALIGN(size * sizeof(struct page)) >> PAGE_SHIFT;
Mel Gorman0e0b8642006-09-27 01:49:56 -07003831 if (realsize >= memmap_pages) {
3832 realsize -= memmap_pages;
Yinghai Lu5594c8c2009-01-06 14:39:14 -08003833 if (memmap_pages)
3834 printk(KERN_DEBUG
3835 " %s zone: %lu pages used for memmap\n",
3836 zone_names[j], memmap_pages);
Mel Gorman0e0b8642006-09-27 01:49:56 -07003837 } else
3838 printk(KERN_WARNING
3839 " %s zone: %lu pages exceeds realsize %lu\n",
3840 zone_names[j], memmap_pages, realsize);
3841
Christoph Lameter62672762007-02-10 01:43:07 -08003842 /* Account for reserved pages */
3843 if (j == 0 && realsize > dma_reserve) {
Mel Gorman0e0b8642006-09-27 01:49:56 -07003844 realsize -= dma_reserve;
Yinghai Lud903ef92008-10-18 20:27:06 -07003845 printk(KERN_DEBUG " %s zone: %lu pages reserved\n",
Christoph Lameter62672762007-02-10 01:43:07 -08003846 zone_names[0], dma_reserve);
Mel Gorman0e0b8642006-09-27 01:49:56 -07003847 }
3848
Christoph Lameter98d2b0e2006-09-25 23:31:12 -07003849 if (!is_highmem_idx(j))
Linus Torvalds1da177e2005-04-16 15:20:36 -07003850 nr_kernel_pages += realsize;
3851 nr_all_pages += realsize;
3852
3853 zone->spanned_pages = size;
3854 zone->present_pages = realsize;
Christoph Lameter96146342006-07-03 00:24:13 -07003855#ifdef CONFIG_NUMA
Christoph Lameterd5f541e2006-09-27 01:50:08 -07003856 zone->node = nid;
Christoph Lameter8417bba2006-09-25 23:31:51 -07003857 zone->min_unmapped_pages = (realsize*sysctl_min_unmapped_ratio)
Christoph Lameter96146342006-07-03 00:24:13 -07003858 / 100;
Christoph Lameter0ff38492006-09-25 23:31:52 -07003859 zone->min_slab_pages = (realsize * sysctl_min_slab_ratio) / 100;
Christoph Lameter96146342006-07-03 00:24:13 -07003860#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07003861 zone->name = zone_names[j];
3862 spin_lock_init(&zone->lock);
3863 spin_lock_init(&zone->lru_lock);
Dave Hansenbdc8cb92005-10-29 18:16:53 -07003864 zone_seqlock_init(zone);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003865 zone->zone_pgdat = pgdat;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003866
Martin Bligh3bb1a8522006-10-28 10:38:24 -07003867 zone->prev_priority = DEF_PRIORITY;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003868
Dave Hansened8ece22005-10-29 18:16:50 -07003869 zone_pcp_init(zone);
Christoph Lameterb69408e2008-10-18 20:26:14 -07003870 for_each_lru(l) {
3871 INIT_LIST_HEAD(&zone->lru[l].list);
Wu Fengguangf8629632009-09-21 17:03:11 -07003872 zone->reclaim_stat.nr_saved_scan[l] = 0;
Christoph Lameterb69408e2008-10-18 20:26:14 -07003873 }
KOSAKI Motohiro6e901572009-01-07 18:08:15 -08003874 zone->reclaim_stat.recent_rotated[0] = 0;
3875 zone->reclaim_stat.recent_rotated[1] = 0;
3876 zone->reclaim_stat.recent_scanned[0] = 0;
3877 zone->reclaim_stat.recent_scanned[1] = 0;
Christoph Lameter2244b952006-06-30 01:55:33 -07003878 zap_zone_vm_stats(zone);
David Rientjese815af92007-10-16 23:25:54 -07003879 zone->flags = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003880 if (!size)
3881 continue;
3882
Mel Gormanba72cb82007-11-28 16:21:13 -08003883 set_pageblock_order(pageblock_default_order());
Mel Gorman835c1342007-10-16 01:25:47 -07003884 setup_usemap(pgdat, zone, size);
Dave Hansena2f3aa022007-01-10 23:15:30 -08003885 ret = init_currently_empty_zone(zone, zone_start_pfn,
3886 size, MEMMAP_EARLY);
Yasunori Goto718127c2006-06-23 02:03:10 -07003887 BUG_ON(ret);
Heiko Carstens76cdd582008-05-14 16:05:52 -07003888 memmap_init(size, nid, j, zone_start_pfn);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003889 zone_start_pfn += size;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003890 }
3891}
3892
Sam Ravnborg577a32f2007-05-17 23:29:25 +02003893static void __init_refok alloc_node_mem_map(struct pglist_data *pgdat)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003894{
Linus Torvalds1da177e2005-04-16 15:20:36 -07003895 /* Skip empty nodes */
3896 if (!pgdat->node_spanned_pages)
3897 return;
3898
Andy Whitcroftd41dee32005-06-23 00:07:54 -07003899#ifdef CONFIG_FLAT_NODE_MEM_MAP
Linus Torvalds1da177e2005-04-16 15:20:36 -07003900 /* ia64 gets its own node_mem_map, before this, without bootmem */
3901 if (!pgdat->node_mem_map) {
Bob Piccoe984bb42006-05-20 15:00:31 -07003902 unsigned long size, start, end;
Andy Whitcroftd41dee32005-06-23 00:07:54 -07003903 struct page *map;
3904
Bob Piccoe984bb42006-05-20 15:00:31 -07003905 /*
3906 * The zone's endpoints aren't required to be MAX_ORDER
3907 * aligned but the node_mem_map endpoints must be in order
3908 * for the buddy allocator to function correctly.
3909 */
3910 start = pgdat->node_start_pfn & ~(MAX_ORDER_NR_PAGES - 1);
3911 end = pgdat->node_start_pfn + pgdat->node_spanned_pages;
3912 end = ALIGN(end, MAX_ORDER_NR_PAGES);
3913 size = (end - start) * sizeof(struct page);
Dave Hansen6f167ec2005-06-23 00:07:39 -07003914 map = alloc_remap(pgdat->node_id, size);
3915 if (!map)
3916 map = alloc_bootmem_node(pgdat, size);
Bob Piccoe984bb42006-05-20 15:00:31 -07003917 pgdat->node_mem_map = map + (pgdat->node_start_pfn - start);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003918 }
Roman Zippel12d810c2007-05-31 00:40:54 -07003919#ifndef CONFIG_NEED_MULTIPLE_NODES
Linus Torvalds1da177e2005-04-16 15:20:36 -07003920 /*
3921 * With no DISCONTIG, the global mem_map is just set as node 0's
3922 */
Mel Gormanc7132162006-09-27 01:49:43 -07003923 if (pgdat == NODE_DATA(0)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07003924 mem_map = NODE_DATA(0)->node_mem_map;
Mel Gormanc7132162006-09-27 01:49:43 -07003925#ifdef CONFIG_ARCH_POPULATES_NODE_MAP
3926 if (page_to_pfn(mem_map) != pgdat->node_start_pfn)
Thomas Bogendoerfer467bc462008-01-08 15:33:11 -08003927 mem_map -= (pgdat->node_start_pfn - ARCH_PFN_OFFSET);
Mel Gormanc7132162006-09-27 01:49:43 -07003928#endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
3929 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07003930#endif
Andy Whitcroftd41dee32005-06-23 00:07:54 -07003931#endif /* CONFIG_FLAT_NODE_MEM_MAP */
Linus Torvalds1da177e2005-04-16 15:20:36 -07003932}
3933
Johannes Weiner9109fb72008-07-23 21:27:20 -07003934void __paginginit free_area_init_node(int nid, unsigned long *zones_size,
3935 unsigned long node_start_pfn, unsigned long *zholes_size)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003936{
Johannes Weiner9109fb72008-07-23 21:27:20 -07003937 pg_data_t *pgdat = NODE_DATA(nid);
3938
Linus Torvalds1da177e2005-04-16 15:20:36 -07003939 pgdat->node_id = nid;
3940 pgdat->node_start_pfn = node_start_pfn;
Mel Gormanc7132162006-09-27 01:49:43 -07003941 calculate_node_totalpages(pgdat, zones_size, zholes_size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003942
3943 alloc_node_mem_map(pgdat);
Yinghai Lue8c27ac2008-06-01 13:15:22 -07003944#ifdef CONFIG_FLAT_NODE_MEM_MAP
3945 printk(KERN_DEBUG "free_area_init_node: node %d, pgdat %08lx, node_mem_map %08lx\n",
3946 nid, (unsigned long)pgdat,
3947 (unsigned long)pgdat->node_mem_map);
3948#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07003949
3950 free_area_init_core(pgdat, zones_size, zholes_size);
3951}
3952
Mel Gormanc7132162006-09-27 01:49:43 -07003953#ifdef CONFIG_ARCH_POPULATES_NODE_MAP
Miklos Szeredi418508c2007-05-23 13:57:55 -07003954
3955#if MAX_NUMNODES > 1
3956/*
3957 * Figure out the number of possible node ids.
3958 */
3959static void __init setup_nr_node_ids(void)
3960{
3961 unsigned int node;
3962 unsigned int highest = 0;
3963
3964 for_each_node_mask(node, node_possible_map)
3965 highest = node;
3966 nr_node_ids = highest + 1;
3967}
3968#else
3969static inline void setup_nr_node_ids(void)
3970{
3971}
3972#endif
3973
Mel Gormanc7132162006-09-27 01:49:43 -07003974/**
3975 * add_active_range - Register a range of PFNs backed by physical memory
3976 * @nid: The node ID the range resides on
3977 * @start_pfn: The start PFN of the available physical memory
3978 * @end_pfn: The end PFN of the available physical memory
3979 *
3980 * These ranges are stored in an early_node_map[] and later used by
3981 * free_area_init_nodes() to calculate zone sizes and holes. If the
3982 * range spans a memory hole, it is up to the architecture to ensure
3983 * the memory is not freed by the bootmem allocator. If possible
3984 * the range being registered will be merged with existing ranges.
3985 */
3986void __init add_active_range(unsigned int nid, unsigned long start_pfn,
3987 unsigned long end_pfn)
3988{
3989 int i;
3990
Mel Gorman6b74ab92008-07-23 21:26:49 -07003991 mminit_dprintk(MMINIT_TRACE, "memory_register",
3992 "Entering add_active_range(%d, %#lx, %#lx) "
3993 "%d entries of %d used\n",
3994 nid, start_pfn, end_pfn,
3995 nr_nodemap_entries, MAX_ACTIVE_REGIONS);
Mel Gormanc7132162006-09-27 01:49:43 -07003996
Mel Gorman2dbb51c2008-07-23 21:26:52 -07003997 mminit_validate_memmodel_limits(&start_pfn, &end_pfn);
3998
Mel Gormanc7132162006-09-27 01:49:43 -07003999 /* Merge with existing active regions if possible */
4000 for (i = 0; i < nr_nodemap_entries; i++) {
4001 if (early_node_map[i].nid != nid)
4002 continue;
4003
4004 /* Skip if an existing region covers this new one */
4005 if (start_pfn >= early_node_map[i].start_pfn &&
4006 end_pfn <= early_node_map[i].end_pfn)
4007 return;
4008
4009 /* Merge forward if suitable */
4010 if (start_pfn <= early_node_map[i].end_pfn &&
4011 end_pfn > early_node_map[i].end_pfn) {
4012 early_node_map[i].end_pfn = end_pfn;
4013 return;
4014 }
4015
4016 /* Merge backward if suitable */
Kazuhisa Ichikawad2dbe082010-01-15 17:01:20 -08004017 if (start_pfn < early_node_map[i].start_pfn &&
Mel Gormanc7132162006-09-27 01:49:43 -07004018 end_pfn >= early_node_map[i].start_pfn) {
4019 early_node_map[i].start_pfn = start_pfn;
4020 return;
4021 }
4022 }
4023
4024 /* Check that early_node_map is large enough */
4025 if (i >= MAX_ACTIVE_REGIONS) {
4026 printk(KERN_CRIT "More than %d memory regions, truncating\n",
4027 MAX_ACTIVE_REGIONS);
4028 return;
4029 }
4030
4031 early_node_map[i].nid = nid;
4032 early_node_map[i].start_pfn = start_pfn;
4033 early_node_map[i].end_pfn = end_pfn;
4034 nr_nodemap_entries = i + 1;
4035}
4036
4037/**
Yinghai Lucc1050b2008-06-13 19:08:52 -07004038 * remove_active_range - Shrink an existing registered range of PFNs
Mel Gormanc7132162006-09-27 01:49:43 -07004039 * @nid: The node id the range is on that should be shrunk
Yinghai Lucc1050b2008-06-13 19:08:52 -07004040 * @start_pfn: The new PFN of the range
4041 * @end_pfn: The new PFN of the range
Mel Gormanc7132162006-09-27 01:49:43 -07004042 *
4043 * i386 with NUMA use alloc_remap() to store a node_mem_map on a local node.
Yinghai Lucc1a9d82008-06-08 19:39:16 -07004044 * The map is kept near the end physical page range that has already been
4045 * registered. This function allows an arch to shrink an existing registered
4046 * range.
Mel Gormanc7132162006-09-27 01:49:43 -07004047 */
Yinghai Lucc1050b2008-06-13 19:08:52 -07004048void __init remove_active_range(unsigned int nid, unsigned long start_pfn,
4049 unsigned long end_pfn)
Mel Gormanc7132162006-09-27 01:49:43 -07004050{
Yinghai Lucc1a9d82008-06-08 19:39:16 -07004051 int i, j;
4052 int removed = 0;
Mel Gormanc7132162006-09-27 01:49:43 -07004053
Yinghai Lucc1050b2008-06-13 19:08:52 -07004054 printk(KERN_DEBUG "remove_active_range (%d, %lu, %lu)\n",
4055 nid, start_pfn, end_pfn);
4056
Mel Gormanc7132162006-09-27 01:49:43 -07004057 /* Find the old active region end and shrink */
Yinghai Lucc1a9d82008-06-08 19:39:16 -07004058 for_each_active_range_index_in_nid(i, nid) {
Yinghai Lucc1050b2008-06-13 19:08:52 -07004059 if (early_node_map[i].start_pfn >= start_pfn &&
4060 early_node_map[i].end_pfn <= end_pfn) {
Yinghai Lucc1a9d82008-06-08 19:39:16 -07004061 /* clear it */
Yinghai Lucc1050b2008-06-13 19:08:52 -07004062 early_node_map[i].start_pfn = 0;
Yinghai Lucc1a9d82008-06-08 19:39:16 -07004063 early_node_map[i].end_pfn = 0;
4064 removed = 1;
4065 continue;
Mel Gormanc7132162006-09-27 01:49:43 -07004066 }
Yinghai Lucc1050b2008-06-13 19:08:52 -07004067 if (early_node_map[i].start_pfn < start_pfn &&
4068 early_node_map[i].end_pfn > start_pfn) {
4069 unsigned long temp_end_pfn = early_node_map[i].end_pfn;
4070 early_node_map[i].end_pfn = start_pfn;
4071 if (temp_end_pfn > end_pfn)
4072 add_active_range(nid, end_pfn, temp_end_pfn);
4073 continue;
4074 }
4075 if (early_node_map[i].start_pfn >= start_pfn &&
4076 early_node_map[i].end_pfn > end_pfn &&
4077 early_node_map[i].start_pfn < end_pfn) {
4078 early_node_map[i].start_pfn = end_pfn;
Yinghai Lucc1a9d82008-06-08 19:39:16 -07004079 continue;
4080 }
4081 }
4082
4083 if (!removed)
4084 return;
4085
4086 /* remove the blank ones */
4087 for (i = nr_nodemap_entries - 1; i > 0; i--) {
4088 if (early_node_map[i].nid != nid)
4089 continue;
4090 if (early_node_map[i].end_pfn)
4091 continue;
4092 /* we found it, get rid of it */
4093 for (j = i; j < nr_nodemap_entries - 1; j++)
4094 memcpy(&early_node_map[j], &early_node_map[j+1],
4095 sizeof(early_node_map[j]));
4096 j = nr_nodemap_entries - 1;
4097 memset(&early_node_map[j], 0, sizeof(early_node_map[j]));
4098 nr_nodemap_entries--;
4099 }
Mel Gormanc7132162006-09-27 01:49:43 -07004100}
4101
4102/**
4103 * remove_all_active_ranges - Remove all currently registered regions
Randy Dunlap88ca3b92006-10-04 02:15:25 -07004104 *
Mel Gormanc7132162006-09-27 01:49:43 -07004105 * During discovery, it may be found that a table like SRAT is invalid
4106 * and an alternative discovery method must be used. This function removes
4107 * all currently registered regions.
4108 */
Randy Dunlap88ca3b92006-10-04 02:15:25 -07004109void __init remove_all_active_ranges(void)
Mel Gormanc7132162006-09-27 01:49:43 -07004110{
4111 memset(early_node_map, 0, sizeof(early_node_map));
4112 nr_nodemap_entries = 0;
4113}
4114
4115/* Compare two active node_active_regions */
4116static int __init cmp_node_active_region(const void *a, const void *b)
4117{
4118 struct node_active_region *arange = (struct node_active_region *)a;
4119 struct node_active_region *brange = (struct node_active_region *)b;
4120
4121 /* Done this way to avoid overflows */
4122 if (arange->start_pfn > brange->start_pfn)
4123 return 1;
4124 if (arange->start_pfn < brange->start_pfn)
4125 return -1;
4126
4127 return 0;
4128}
4129
4130/* sort the node_map by start_pfn */
Yinghai Lu32996252009-12-15 17:59:02 -08004131void __init sort_node_map(void)
Mel Gormanc7132162006-09-27 01:49:43 -07004132{
4133 sort(early_node_map, (size_t)nr_nodemap_entries,
4134 sizeof(struct node_active_region),
4135 cmp_node_active_region, NULL);
4136}
4137
Mel Gormana6af2bc2007-02-10 01:42:57 -08004138/* Find the lowest pfn for a node */
Adrian Bunkb69a7282008-07-23 21:28:12 -07004139static unsigned long __init find_min_pfn_for_node(int nid)
Mel Gormanc7132162006-09-27 01:49:43 -07004140{
4141 int i;
Mel Gormana6af2bc2007-02-10 01:42:57 -08004142 unsigned long min_pfn = ULONG_MAX;
Mel Gorman1abbfb42006-11-23 12:01:41 +00004143
Mel Gormanc7132162006-09-27 01:49:43 -07004144 /* Assuming a sorted map, the first range found has the starting pfn */
4145 for_each_active_range_index_in_nid(i, nid)
Mel Gormana6af2bc2007-02-10 01:42:57 -08004146 min_pfn = min(min_pfn, early_node_map[i].start_pfn);
Mel Gormanc7132162006-09-27 01:49:43 -07004147
Mel Gormana6af2bc2007-02-10 01:42:57 -08004148 if (min_pfn == ULONG_MAX) {
4149 printk(KERN_WARNING
Paul Jackson2bc0d262008-06-22 07:22:17 -07004150 "Could not find start_pfn for node %d\n", nid);
Mel Gormana6af2bc2007-02-10 01:42:57 -08004151 return 0;
4152 }
4153
4154 return min_pfn;
Mel Gormanc7132162006-09-27 01:49:43 -07004155}
4156
4157/**
4158 * find_min_pfn_with_active_regions - Find the minimum PFN registered
4159 *
4160 * It returns the minimum PFN based on information provided via
Randy Dunlap88ca3b92006-10-04 02:15:25 -07004161 * add_active_range().
Mel Gormanc7132162006-09-27 01:49:43 -07004162 */
4163unsigned long __init find_min_pfn_with_active_regions(void)
4164{
4165 return find_min_pfn_for_node(MAX_NUMNODES);
4166}
4167
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07004168/*
4169 * early_calculate_totalpages()
4170 * Sum pages in active regions for movable zone.
4171 * Populate N_HIGH_MEMORY for calculating usable_nodes.
4172 */
Adrian Bunk484f51f2007-10-16 01:26:03 -07004173static unsigned long __init early_calculate_totalpages(void)
Mel Gorman7e63efe2007-07-17 04:03:15 -07004174{
4175 int i;
4176 unsigned long totalpages = 0;
4177
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07004178 for (i = 0; i < nr_nodemap_entries; i++) {
4179 unsigned long pages = early_node_map[i].end_pfn -
Mel Gorman7e63efe2007-07-17 04:03:15 -07004180 early_node_map[i].start_pfn;
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07004181 totalpages += pages;
4182 if (pages)
4183 node_set_state(early_node_map[i].nid, N_HIGH_MEMORY);
4184 }
4185 return totalpages;
Mel Gorman7e63efe2007-07-17 04:03:15 -07004186}
4187
Mel Gorman2a1e2742007-07-17 04:03:12 -07004188/*
4189 * Find the PFN the Movable zone begins in each node. Kernel memory
4190 * is spread evenly between nodes as long as the nodes have enough
4191 * memory. When they don't, some nodes will have more kernelcore than
4192 * others
4193 */
Adrian Bunkb69a7282008-07-23 21:28:12 -07004194static void __init find_zone_movable_pfns_for_nodes(unsigned long *movable_pfn)
Mel Gorman2a1e2742007-07-17 04:03:12 -07004195{
4196 int i, nid;
4197 unsigned long usable_startpfn;
4198 unsigned long kernelcore_node, kernelcore_remaining;
Yinghai Lu66918dc2009-06-30 11:41:37 -07004199 /* save the state before borrow the nodemask */
4200 nodemask_t saved_node_state = node_states[N_HIGH_MEMORY];
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07004201 unsigned long totalpages = early_calculate_totalpages();
4202 int usable_nodes = nodes_weight(node_states[N_HIGH_MEMORY]);
Mel Gorman2a1e2742007-07-17 04:03:12 -07004203
Mel Gorman7e63efe2007-07-17 04:03:15 -07004204 /*
4205 * If movablecore was specified, calculate what size of
4206 * kernelcore that corresponds so that memory usable for
4207 * any allocation type is evenly spread. If both kernelcore
4208 * and movablecore are specified, then the value of kernelcore
4209 * will be used for required_kernelcore if it's greater than
4210 * what movablecore would have allowed.
4211 */
4212 if (required_movablecore) {
Mel Gorman7e63efe2007-07-17 04:03:15 -07004213 unsigned long corepages;
4214
4215 /*
4216 * Round-up so that ZONE_MOVABLE is at least as large as what
4217 * was requested by the user
4218 */
4219 required_movablecore =
4220 roundup(required_movablecore, MAX_ORDER_NR_PAGES);
4221 corepages = totalpages - required_movablecore;
4222
4223 required_kernelcore = max(required_kernelcore, corepages);
4224 }
4225
Mel Gorman2a1e2742007-07-17 04:03:12 -07004226 /* If kernelcore was not specified, there is no ZONE_MOVABLE */
4227 if (!required_kernelcore)
Yinghai Lu66918dc2009-06-30 11:41:37 -07004228 goto out;
Mel Gorman2a1e2742007-07-17 04:03:12 -07004229
4230 /* usable_startpfn is the lowest possible pfn ZONE_MOVABLE can be at */
4231 find_usable_zone_for_movable();
4232 usable_startpfn = arch_zone_lowest_possible_pfn[movable_zone];
4233
4234restart:
4235 /* Spread kernelcore memory as evenly as possible throughout nodes */
4236 kernelcore_node = required_kernelcore / usable_nodes;
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07004237 for_each_node_state(nid, N_HIGH_MEMORY) {
Mel Gorman2a1e2742007-07-17 04:03:12 -07004238 /*
4239 * Recalculate kernelcore_node if the division per node
4240 * now exceeds what is necessary to satisfy the requested
4241 * amount of memory for the kernel
4242 */
4243 if (required_kernelcore < kernelcore_node)
4244 kernelcore_node = required_kernelcore / usable_nodes;
4245
4246 /*
4247 * As the map is walked, we track how much memory is usable
4248 * by the kernel using kernelcore_remaining. When it is
4249 * 0, the rest of the node is usable by ZONE_MOVABLE
4250 */
4251 kernelcore_remaining = kernelcore_node;
4252
4253 /* Go through each range of PFNs within this node */
4254 for_each_active_range_index_in_nid(i, nid) {
4255 unsigned long start_pfn, end_pfn;
4256 unsigned long size_pages;
4257
4258 start_pfn = max(early_node_map[i].start_pfn,
4259 zone_movable_pfn[nid]);
4260 end_pfn = early_node_map[i].end_pfn;
4261 if (start_pfn >= end_pfn)
4262 continue;
4263
4264 /* Account for what is only usable for kernelcore */
4265 if (start_pfn < usable_startpfn) {
4266 unsigned long kernel_pages;
4267 kernel_pages = min(end_pfn, usable_startpfn)
4268 - start_pfn;
4269
4270 kernelcore_remaining -= min(kernel_pages,
4271 kernelcore_remaining);
4272 required_kernelcore -= min(kernel_pages,
4273 required_kernelcore);
4274
4275 /* Continue if range is now fully accounted */
4276 if (end_pfn <= usable_startpfn) {
4277
4278 /*
4279 * Push zone_movable_pfn to the end so
4280 * that if we have to rebalance
4281 * kernelcore across nodes, we will
4282 * not double account here
4283 */
4284 zone_movable_pfn[nid] = end_pfn;
4285 continue;
4286 }
4287 start_pfn = usable_startpfn;
4288 }
4289
4290 /*
4291 * The usable PFN range for ZONE_MOVABLE is from
4292 * start_pfn->end_pfn. Calculate size_pages as the
4293 * number of pages used as kernelcore
4294 */
4295 size_pages = end_pfn - start_pfn;
4296 if (size_pages > kernelcore_remaining)
4297 size_pages = kernelcore_remaining;
4298 zone_movable_pfn[nid] = start_pfn + size_pages;
4299
4300 /*
4301 * Some kernelcore has been met, update counts and
4302 * break if the kernelcore for this node has been
4303 * satisified
4304 */
4305 required_kernelcore -= min(required_kernelcore,
4306 size_pages);
4307 kernelcore_remaining -= size_pages;
4308 if (!kernelcore_remaining)
4309 break;
4310 }
4311 }
4312
4313 /*
4314 * If there is still required_kernelcore, we do another pass with one
4315 * less node in the count. This will push zone_movable_pfn[nid] further
4316 * along on the nodes that still have memory until kernelcore is
4317 * satisified
4318 */
4319 usable_nodes--;
4320 if (usable_nodes && required_kernelcore > usable_nodes)
4321 goto restart;
4322
4323 /* Align start of ZONE_MOVABLE on all nids to MAX_ORDER_NR_PAGES */
4324 for (nid = 0; nid < MAX_NUMNODES; nid++)
4325 zone_movable_pfn[nid] =
4326 roundup(zone_movable_pfn[nid], MAX_ORDER_NR_PAGES);
Yinghai Lu66918dc2009-06-30 11:41:37 -07004327
4328out:
4329 /* restore the node_state */
4330 node_states[N_HIGH_MEMORY] = saved_node_state;
Mel Gorman2a1e2742007-07-17 04:03:12 -07004331}
4332
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07004333/* Any regular memory on that node ? */
4334static void check_for_regular_memory(pg_data_t *pgdat)
4335{
4336#ifdef CONFIG_HIGHMEM
4337 enum zone_type zone_type;
4338
4339 for (zone_type = 0; zone_type <= ZONE_NORMAL; zone_type++) {
4340 struct zone *zone = &pgdat->node_zones[zone_type];
4341 if (zone->present_pages)
4342 node_set_state(zone_to_nid(zone), N_NORMAL_MEMORY);
4343 }
4344#endif
4345}
4346
Mel Gormanc7132162006-09-27 01:49:43 -07004347/**
4348 * free_area_init_nodes - Initialise all pg_data_t and zone data
Randy Dunlap88ca3b92006-10-04 02:15:25 -07004349 * @max_zone_pfn: an array of max PFNs for each zone
Mel Gormanc7132162006-09-27 01:49:43 -07004350 *
4351 * This will call free_area_init_node() for each active node in the system.
4352 * Using the page ranges provided by add_active_range(), the size of each
4353 * zone in each node and their holes is calculated. If the maximum PFN
4354 * between two adjacent zones match, it is assumed that the zone is empty.
4355 * For example, if arch_max_dma_pfn == arch_max_dma32_pfn, it is assumed
4356 * that arch_max_dma32_pfn has no pages. It is also assumed that a zone
4357 * starts where the previous one ended. For example, ZONE_DMA32 starts
4358 * at arch_max_dma_pfn.
4359 */
4360void __init free_area_init_nodes(unsigned long *max_zone_pfn)
4361{
4362 unsigned long nid;
Andrew Mortondb991002008-10-15 22:01:07 -07004363 int i;
Mel Gormanc7132162006-09-27 01:49:43 -07004364
Mel Gormana6af2bc2007-02-10 01:42:57 -08004365 /* Sort early_node_map as initialisation assumes it is sorted */
4366 sort_node_map();
4367
Mel Gormanc7132162006-09-27 01:49:43 -07004368 /* Record where the zone boundaries are */
4369 memset(arch_zone_lowest_possible_pfn, 0,
4370 sizeof(arch_zone_lowest_possible_pfn));
4371 memset(arch_zone_highest_possible_pfn, 0,
4372 sizeof(arch_zone_highest_possible_pfn));
4373 arch_zone_lowest_possible_pfn[0] = find_min_pfn_with_active_regions();
4374 arch_zone_highest_possible_pfn[0] = max_zone_pfn[0];
4375 for (i = 1; i < MAX_NR_ZONES; i++) {
Mel Gorman2a1e2742007-07-17 04:03:12 -07004376 if (i == ZONE_MOVABLE)
4377 continue;
Mel Gormanc7132162006-09-27 01:49:43 -07004378 arch_zone_lowest_possible_pfn[i] =
4379 arch_zone_highest_possible_pfn[i-1];
4380 arch_zone_highest_possible_pfn[i] =
4381 max(max_zone_pfn[i], arch_zone_lowest_possible_pfn[i]);
4382 }
Mel Gorman2a1e2742007-07-17 04:03:12 -07004383 arch_zone_lowest_possible_pfn[ZONE_MOVABLE] = 0;
4384 arch_zone_highest_possible_pfn[ZONE_MOVABLE] = 0;
4385
4386 /* Find the PFNs that ZONE_MOVABLE begins at in each node */
4387 memset(zone_movable_pfn, 0, sizeof(zone_movable_pfn));
4388 find_zone_movable_pfns_for_nodes(zone_movable_pfn);
Mel Gormanc7132162006-09-27 01:49:43 -07004389
Mel Gormanc7132162006-09-27 01:49:43 -07004390 /* Print out the zone ranges */
4391 printk("Zone PFN ranges:\n");
Mel Gorman2a1e2742007-07-17 04:03:12 -07004392 for (i = 0; i < MAX_NR_ZONES; i++) {
4393 if (i == ZONE_MOVABLE)
4394 continue;
David Rientjes72f0ba02010-03-05 13:42:14 -08004395 printk(" %-8s ", zone_names[i]);
4396 if (arch_zone_lowest_possible_pfn[i] ==
4397 arch_zone_highest_possible_pfn[i])
4398 printk("empty\n");
4399 else
4400 printk("%0#10lx -> %0#10lx\n",
Mel Gormanc7132162006-09-27 01:49:43 -07004401 arch_zone_lowest_possible_pfn[i],
4402 arch_zone_highest_possible_pfn[i]);
Mel Gorman2a1e2742007-07-17 04:03:12 -07004403 }
4404
4405 /* Print out the PFNs ZONE_MOVABLE begins at in each node */
4406 printk("Movable zone start PFN for each node\n");
4407 for (i = 0; i < MAX_NUMNODES; i++) {
4408 if (zone_movable_pfn[i])
4409 printk(" Node %d: %lu\n", i, zone_movable_pfn[i]);
4410 }
Mel Gormanc7132162006-09-27 01:49:43 -07004411
4412 /* Print out the early_node_map[] */
4413 printk("early_node_map[%d] active PFN ranges\n", nr_nodemap_entries);
4414 for (i = 0; i < nr_nodemap_entries; i++)
Paul Jackson5dab8ec2008-06-25 05:44:40 -07004415 printk(" %3d: %0#10lx -> %0#10lx\n", early_node_map[i].nid,
Mel Gormanc7132162006-09-27 01:49:43 -07004416 early_node_map[i].start_pfn,
4417 early_node_map[i].end_pfn);
4418
4419 /* Initialise every node */
Mel Gorman708614e2008-07-23 21:26:51 -07004420 mminit_verify_pageflags_layout();
Christoph Lameter8ef82862007-02-20 13:57:52 -08004421 setup_nr_node_ids();
Mel Gormanc7132162006-09-27 01:49:43 -07004422 for_each_online_node(nid) {
4423 pg_data_t *pgdat = NODE_DATA(nid);
Johannes Weiner9109fb72008-07-23 21:27:20 -07004424 free_area_init_node(nid, NULL,
Mel Gormanc7132162006-09-27 01:49:43 -07004425 find_min_pfn_for_node(nid), NULL);
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07004426
4427 /* Any memory on that node */
4428 if (pgdat->node_present_pages)
4429 node_set_state(nid, N_HIGH_MEMORY);
4430 check_for_regular_memory(pgdat);
Mel Gormanc7132162006-09-27 01:49:43 -07004431 }
4432}
Mel Gorman2a1e2742007-07-17 04:03:12 -07004433
Mel Gorman7e63efe2007-07-17 04:03:15 -07004434static int __init cmdline_parse_core(char *p, unsigned long *core)
Mel Gorman2a1e2742007-07-17 04:03:12 -07004435{
4436 unsigned long long coremem;
4437 if (!p)
4438 return -EINVAL;
4439
4440 coremem = memparse(p, &p);
Mel Gorman7e63efe2007-07-17 04:03:15 -07004441 *core = coremem >> PAGE_SHIFT;
Mel Gorman2a1e2742007-07-17 04:03:12 -07004442
Mel Gorman7e63efe2007-07-17 04:03:15 -07004443 /* Paranoid check that UL is enough for the coremem value */
Mel Gorman2a1e2742007-07-17 04:03:12 -07004444 WARN_ON((coremem >> PAGE_SHIFT) > ULONG_MAX);
4445
4446 return 0;
4447}
Mel Gormaned7ed362007-07-17 04:03:14 -07004448
Mel Gorman7e63efe2007-07-17 04:03:15 -07004449/*
4450 * kernelcore=size sets the amount of memory for use for allocations that
4451 * cannot be reclaimed or migrated.
4452 */
4453static int __init cmdline_parse_kernelcore(char *p)
4454{
4455 return cmdline_parse_core(p, &required_kernelcore);
4456}
4457
4458/*
4459 * movablecore=size sets the amount of memory for use for allocations that
4460 * can be reclaimed or migrated.
4461 */
4462static int __init cmdline_parse_movablecore(char *p)
4463{
4464 return cmdline_parse_core(p, &required_movablecore);
4465}
4466
Mel Gormaned7ed362007-07-17 04:03:14 -07004467early_param("kernelcore", cmdline_parse_kernelcore);
Mel Gorman7e63efe2007-07-17 04:03:15 -07004468early_param("movablecore", cmdline_parse_movablecore);
Mel Gormaned7ed362007-07-17 04:03:14 -07004469
Mel Gormanc7132162006-09-27 01:49:43 -07004470#endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
4471
Mel Gorman0e0b8642006-09-27 01:49:56 -07004472/**
Randy Dunlap88ca3b92006-10-04 02:15:25 -07004473 * set_dma_reserve - set the specified number of pages reserved in the first zone
4474 * @new_dma_reserve: The number of pages to mark reserved
Mel Gorman0e0b8642006-09-27 01:49:56 -07004475 *
4476 * The per-cpu batchsize and zone watermarks are determined by present_pages.
4477 * In the DMA zone, a significant percentage may be consumed by kernel image
4478 * and other unfreeable allocations which can skew the watermarks badly. This
Randy Dunlap88ca3b92006-10-04 02:15:25 -07004479 * function may optionally be used to account for unfreeable pages in the
4480 * first zone (e.g., ZONE_DMA). The effect will be lower watermarks and
4481 * smaller per-cpu batchsize.
Mel Gorman0e0b8642006-09-27 01:49:56 -07004482 */
4483void __init set_dma_reserve(unsigned long new_dma_reserve)
4484{
4485 dma_reserve = new_dma_reserve;
4486}
4487
Dave Hansen93b75042005-06-23 00:07:47 -07004488#ifndef CONFIG_NEED_MULTIPLE_NODES
Yinghai Lu08677212010-02-10 01:20:20 -08004489struct pglist_data __refdata contig_page_data = {
4490#ifndef CONFIG_NO_BOOTMEM
4491 .bdata = &bootmem_node_data[0]
4492#endif
4493 };
Linus Torvalds1da177e2005-04-16 15:20:36 -07004494EXPORT_SYMBOL(contig_page_data);
Dave Hansen93b75042005-06-23 00:07:47 -07004495#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07004496
4497void __init free_area_init(unsigned long *zones_size)
4498{
Johannes Weiner9109fb72008-07-23 21:27:20 -07004499 free_area_init_node(0, zones_size,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004500 __pa(PAGE_OFFSET) >> PAGE_SHIFT, NULL);
4501}
Linus Torvalds1da177e2005-04-16 15:20:36 -07004502
Linus Torvalds1da177e2005-04-16 15:20:36 -07004503static int page_alloc_cpu_notify(struct notifier_block *self,
4504 unsigned long action, void *hcpu)
4505{
4506 int cpu = (unsigned long)hcpu;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004507
Rafael J. Wysocki8bb78442007-05-09 02:35:10 -07004508 if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) {
Christoph Lameter9f8f2172008-02-04 22:29:11 -08004509 drain_pages(cpu);
4510
4511 /*
4512 * Spill the event counters of the dead processor
4513 * into the current processors event counters.
4514 * This artificially elevates the count of the current
4515 * processor.
4516 */
Christoph Lameterf8891e52006-06-30 01:55:45 -07004517 vm_events_fold_cpu(cpu);
Christoph Lameter9f8f2172008-02-04 22:29:11 -08004518
4519 /*
4520 * Zero the differential counters of the dead processor
4521 * so that the vm statistics are consistent.
4522 *
4523 * This is only okay since the processor is dead and cannot
4524 * race with what we are doing.
4525 */
Christoph Lameter2244b952006-06-30 01:55:33 -07004526 refresh_cpu_vm_stats(cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004527 }
4528 return NOTIFY_OK;
4529}
Linus Torvalds1da177e2005-04-16 15:20:36 -07004530
4531void __init page_alloc_init(void)
4532{
4533 hotcpu_notifier(page_alloc_cpu_notify, 0);
4534}
4535
4536/*
Hideo AOKIcb45b0e2006-04-10 22:52:59 -07004537 * calculate_totalreserve_pages - called when sysctl_lower_zone_reserve_ratio
4538 * or min_free_kbytes changes.
4539 */
4540static void calculate_totalreserve_pages(void)
4541{
4542 struct pglist_data *pgdat;
4543 unsigned long reserve_pages = 0;
Christoph Lameter2f6726e2006-09-25 23:31:18 -07004544 enum zone_type i, j;
Hideo AOKIcb45b0e2006-04-10 22:52:59 -07004545
4546 for_each_online_pgdat(pgdat) {
4547 for (i = 0; i < MAX_NR_ZONES; i++) {
4548 struct zone *zone = pgdat->node_zones + i;
4549 unsigned long max = 0;
4550
4551 /* Find valid and maximum lowmem_reserve in the zone */
4552 for (j = i; j < MAX_NR_ZONES; j++) {
4553 if (zone->lowmem_reserve[j] > max)
4554 max = zone->lowmem_reserve[j];
4555 }
4556
Mel Gorman41858962009-06-16 15:32:12 -07004557 /* we treat the high watermark as reserved pages. */
4558 max += high_wmark_pages(zone);
Hideo AOKIcb45b0e2006-04-10 22:52:59 -07004559
4560 if (max > zone->present_pages)
4561 max = zone->present_pages;
4562 reserve_pages += max;
4563 }
4564 }
4565 totalreserve_pages = reserve_pages;
4566}
4567
4568/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07004569 * setup_per_zone_lowmem_reserve - called whenever
4570 * sysctl_lower_zone_reserve_ratio changes. Ensures that each zone
4571 * has a correct pages reserved value, so an adequate number of
4572 * pages are left in the zone after a successful __alloc_pages().
4573 */
4574static void setup_per_zone_lowmem_reserve(void)
4575{
4576 struct pglist_data *pgdat;
Christoph Lameter2f6726e2006-09-25 23:31:18 -07004577 enum zone_type j, idx;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004578
KAMEZAWA Hiroyukiec936fc2006-03-27 01:15:59 -08004579 for_each_online_pgdat(pgdat) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07004580 for (j = 0; j < MAX_NR_ZONES; j++) {
4581 struct zone *zone = pgdat->node_zones + j;
4582 unsigned long present_pages = zone->present_pages;
4583
4584 zone->lowmem_reserve[j] = 0;
4585
Christoph Lameter2f6726e2006-09-25 23:31:18 -07004586 idx = j;
4587 while (idx) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07004588 struct zone *lower_zone;
4589
Christoph Lameter2f6726e2006-09-25 23:31:18 -07004590 idx--;
4591
Linus Torvalds1da177e2005-04-16 15:20:36 -07004592 if (sysctl_lowmem_reserve_ratio[idx] < 1)
4593 sysctl_lowmem_reserve_ratio[idx] = 1;
4594
4595 lower_zone = pgdat->node_zones + idx;
4596 lower_zone->lowmem_reserve[j] = present_pages /
4597 sysctl_lowmem_reserve_ratio[idx];
4598 present_pages += lower_zone->present_pages;
4599 }
4600 }
4601 }
Hideo AOKIcb45b0e2006-04-10 22:52:59 -07004602
4603 /* update totalreserve_pages */
4604 calculate_totalreserve_pages();
Linus Torvalds1da177e2005-04-16 15:20:36 -07004605}
4606
Randy Dunlap88ca3b92006-10-04 02:15:25 -07004607/**
Minchan Kimbc75d332009-06-16 15:32:48 -07004608 * setup_per_zone_wmarks - called when min_free_kbytes changes
Minchan Kimbce73942009-06-16 15:32:50 -07004609 * or when memory is hot-{added|removed}
Randy Dunlap88ca3b92006-10-04 02:15:25 -07004610 *
Minchan Kimbc75d332009-06-16 15:32:48 -07004611 * Ensures that the watermark[min,low,high] values for each zone are set
4612 * correctly with respect to min_free_kbytes.
Linus Torvalds1da177e2005-04-16 15:20:36 -07004613 */
Minchan Kimbc75d332009-06-16 15:32:48 -07004614void setup_per_zone_wmarks(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -07004615{
4616 unsigned long pages_min = min_free_kbytes >> (PAGE_SHIFT - 10);
4617 unsigned long lowmem_pages = 0;
4618 struct zone *zone;
4619 unsigned long flags;
4620
4621 /* Calculate total number of !ZONE_HIGHMEM pages */
4622 for_each_zone(zone) {
4623 if (!is_highmem(zone))
4624 lowmem_pages += zone->present_pages;
4625 }
4626
4627 for_each_zone(zone) {
Andrew Mortonac924c62006-05-15 09:43:59 -07004628 u64 tmp;
4629
Gerald Schaefer1125b4e2008-10-18 20:27:11 -07004630 spin_lock_irqsave(&zone->lock, flags);
Andrew Mortonac924c62006-05-15 09:43:59 -07004631 tmp = (u64)pages_min * zone->present_pages;
4632 do_div(tmp, lowmem_pages);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004633 if (is_highmem(zone)) {
4634 /*
Nick Piggin669ed172005-11-13 16:06:45 -08004635 * __GFP_HIGH and PF_MEMALLOC allocations usually don't
4636 * need highmem pages, so cap pages_min to a small
4637 * value here.
4638 *
Mel Gorman41858962009-06-16 15:32:12 -07004639 * The WMARK_HIGH-WMARK_LOW and (WMARK_LOW-WMARK_MIN)
Nick Piggin669ed172005-11-13 16:06:45 -08004640 * deltas controls asynch page reclaim, and so should
4641 * not be capped for highmem.
Linus Torvalds1da177e2005-04-16 15:20:36 -07004642 */
4643 int min_pages;
4644
4645 min_pages = zone->present_pages / 1024;
4646 if (min_pages < SWAP_CLUSTER_MAX)
4647 min_pages = SWAP_CLUSTER_MAX;
4648 if (min_pages > 128)
4649 min_pages = 128;
Mel Gorman41858962009-06-16 15:32:12 -07004650 zone->watermark[WMARK_MIN] = min_pages;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004651 } else {
Nick Piggin669ed172005-11-13 16:06:45 -08004652 /*
4653 * If it's a lowmem zone, reserve a number of pages
Linus Torvalds1da177e2005-04-16 15:20:36 -07004654 * proportionate to the zone's size.
4655 */
Mel Gorman41858962009-06-16 15:32:12 -07004656 zone->watermark[WMARK_MIN] = tmp;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004657 }
4658
Mel Gorman41858962009-06-16 15:32:12 -07004659 zone->watermark[WMARK_LOW] = min_wmark_pages(zone) + (tmp >> 2);
4660 zone->watermark[WMARK_HIGH] = min_wmark_pages(zone) + (tmp >> 1);
Mel Gorman56fd56b2007-10-16 01:25:58 -07004661 setup_zone_migrate_reserve(zone);
Gerald Schaefer1125b4e2008-10-18 20:27:11 -07004662 spin_unlock_irqrestore(&zone->lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004663 }
Hideo AOKIcb45b0e2006-04-10 22:52:59 -07004664
4665 /* update totalreserve_pages */
4666 calculate_totalreserve_pages();
Linus Torvalds1da177e2005-04-16 15:20:36 -07004667}
4668
Randy Dunlap55a44622009-09-21 17:01:20 -07004669/*
Rik van Riel556adec2008-10-18 20:26:34 -07004670 * The inactive anon list should be small enough that the VM never has to
4671 * do too much work, but large enough that each inactive page has a chance
4672 * to be referenced again before it is swapped out.
4673 *
4674 * The inactive_anon ratio is the target ratio of ACTIVE_ANON to
4675 * INACTIVE_ANON pages on this zone's LRU, maintained by the
4676 * pageout code. A zone->inactive_ratio of 3 means 3:1 or 25% of
4677 * the anonymous pages are kept on the inactive list.
4678 *
4679 * total target max
4680 * memory ratio inactive anon
4681 * -------------------------------------
4682 * 10MB 1 5MB
4683 * 100MB 1 50MB
4684 * 1GB 3 250MB
4685 * 10GB 10 0.9GB
4686 * 100GB 31 3GB
4687 * 1TB 101 10GB
4688 * 10TB 320 32GB
4689 */
Minchan Kim96cb4df2009-06-16 15:32:49 -07004690void calculate_zone_inactive_ratio(struct zone *zone)
4691{
4692 unsigned int gb, ratio;
4693
4694 /* Zone size in gigabytes */
4695 gb = zone->present_pages >> (30 - PAGE_SHIFT);
4696 if (gb)
4697 ratio = int_sqrt(10 * gb);
4698 else
4699 ratio = 1;
4700
4701 zone->inactive_ratio = ratio;
4702}
4703
Cyrill Gorcunove9bb35d2009-06-16 15:32:32 -07004704static void __init setup_per_zone_inactive_ratio(void)
Rik van Riel556adec2008-10-18 20:26:34 -07004705{
4706 struct zone *zone;
4707
Minchan Kim96cb4df2009-06-16 15:32:49 -07004708 for_each_zone(zone)
4709 calculate_zone_inactive_ratio(zone);
Rik van Riel556adec2008-10-18 20:26:34 -07004710}
4711
Linus Torvalds1da177e2005-04-16 15:20:36 -07004712/*
4713 * Initialise min_free_kbytes.
4714 *
4715 * For small machines we want it small (128k min). For large machines
4716 * we want it large (64MB max). But it is not linear, because network
4717 * bandwidth does not increase linearly with machine size. We use
4718 *
4719 * min_free_kbytes = 4 * sqrt(lowmem_kbytes), for better accuracy:
4720 * min_free_kbytes = sqrt(lowmem_kbytes * 16)
4721 *
4722 * which yields
4723 *
4724 * 16MB: 512k
4725 * 32MB: 724k
4726 * 64MB: 1024k
4727 * 128MB: 1448k
4728 * 256MB: 2048k
4729 * 512MB: 2896k
4730 * 1024MB: 4096k
4731 * 2048MB: 5792k
4732 * 4096MB: 8192k
4733 * 8192MB: 11584k
4734 * 16384MB: 16384k
4735 */
Minchan Kimbc75d332009-06-16 15:32:48 -07004736static int __init init_per_zone_wmark_min(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -07004737{
4738 unsigned long lowmem_kbytes;
4739
4740 lowmem_kbytes = nr_free_buffer_pages() * (PAGE_SIZE >> 10);
4741
4742 min_free_kbytes = int_sqrt(lowmem_kbytes * 16);
4743 if (min_free_kbytes < 128)
4744 min_free_kbytes = 128;
4745 if (min_free_kbytes > 65536)
4746 min_free_kbytes = 65536;
Minchan Kimbc75d332009-06-16 15:32:48 -07004747 setup_per_zone_wmarks();
Linus Torvalds1da177e2005-04-16 15:20:36 -07004748 setup_per_zone_lowmem_reserve();
Rik van Riel556adec2008-10-18 20:26:34 -07004749 setup_per_zone_inactive_ratio();
Linus Torvalds1da177e2005-04-16 15:20:36 -07004750 return 0;
4751}
Minchan Kimbc75d332009-06-16 15:32:48 -07004752module_init(init_per_zone_wmark_min)
Linus Torvalds1da177e2005-04-16 15:20:36 -07004753
4754/*
4755 * min_free_kbytes_sysctl_handler - just a wrapper around proc_dointvec() so
4756 * that we can call two helper functions whenever min_free_kbytes
4757 * changes.
4758 */
4759int min_free_kbytes_sysctl_handler(ctl_table *table, int write,
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07004760 void __user *buffer, size_t *length, loff_t *ppos)
Linus Torvalds1da177e2005-04-16 15:20:36 -07004761{
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07004762 proc_dointvec(table, write, buffer, length, ppos);
Mel Gorman3b1d92c2007-05-06 14:49:30 -07004763 if (write)
Minchan Kimbc75d332009-06-16 15:32:48 -07004764 setup_per_zone_wmarks();
Linus Torvalds1da177e2005-04-16 15:20:36 -07004765 return 0;
4766}
4767
Christoph Lameter96146342006-07-03 00:24:13 -07004768#ifdef CONFIG_NUMA
4769int sysctl_min_unmapped_ratio_sysctl_handler(ctl_table *table, int write,
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07004770 void __user *buffer, size_t *length, loff_t *ppos)
Christoph Lameter96146342006-07-03 00:24:13 -07004771{
4772 struct zone *zone;
4773 int rc;
4774
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07004775 rc = proc_dointvec_minmax(table, write, buffer, length, ppos);
Christoph Lameter96146342006-07-03 00:24:13 -07004776 if (rc)
4777 return rc;
4778
4779 for_each_zone(zone)
Christoph Lameter8417bba2006-09-25 23:31:51 -07004780 zone->min_unmapped_pages = (zone->present_pages *
Christoph Lameter96146342006-07-03 00:24:13 -07004781 sysctl_min_unmapped_ratio) / 100;
4782 return 0;
4783}
Christoph Lameter0ff38492006-09-25 23:31:52 -07004784
4785int sysctl_min_slab_ratio_sysctl_handler(ctl_table *table, int write,
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07004786 void __user *buffer, size_t *length, loff_t *ppos)
Christoph Lameter0ff38492006-09-25 23:31:52 -07004787{
4788 struct zone *zone;
4789 int rc;
4790
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07004791 rc = proc_dointvec_minmax(table, write, buffer, length, ppos);
Christoph Lameter0ff38492006-09-25 23:31:52 -07004792 if (rc)
4793 return rc;
4794
4795 for_each_zone(zone)
4796 zone->min_slab_pages = (zone->present_pages *
4797 sysctl_min_slab_ratio) / 100;
4798 return 0;
4799}
Christoph Lameter96146342006-07-03 00:24:13 -07004800#endif
4801
Linus Torvalds1da177e2005-04-16 15:20:36 -07004802/*
4803 * lowmem_reserve_ratio_sysctl_handler - just a wrapper around
4804 * proc_dointvec() so that we can call setup_per_zone_lowmem_reserve()
4805 * whenever sysctl_lowmem_reserve_ratio changes.
4806 *
4807 * The reserve ratio obviously has absolutely no relation with the
Mel Gorman41858962009-06-16 15:32:12 -07004808 * minimum watermarks. The lowmem reserve ratio can only make sense
Linus Torvalds1da177e2005-04-16 15:20:36 -07004809 * if in function of the boot time zone sizes.
4810 */
4811int lowmem_reserve_ratio_sysctl_handler(ctl_table *table, int write,
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07004812 void __user *buffer, size_t *length, loff_t *ppos)
Linus Torvalds1da177e2005-04-16 15:20:36 -07004813{
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07004814 proc_dointvec_minmax(table, write, buffer, length, ppos);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004815 setup_per_zone_lowmem_reserve();
4816 return 0;
4817}
4818
Rohit Seth8ad4b1f2006-01-08 01:00:40 -08004819/*
4820 * percpu_pagelist_fraction - changes the pcp->high for each zone on each
4821 * cpu. It is the fraction of total pages in each zone that a hot per cpu pagelist
4822 * can have before it gets flushed back to buddy allocator.
4823 */
4824
4825int percpu_pagelist_fraction_sysctl_handler(ctl_table *table, int write,
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07004826 void __user *buffer, size_t *length, loff_t *ppos)
Rohit Seth8ad4b1f2006-01-08 01:00:40 -08004827{
4828 struct zone *zone;
4829 unsigned int cpu;
4830 int ret;
4831
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07004832 ret = proc_dointvec_minmax(table, write, buffer, length, ppos);
Rohit Seth8ad4b1f2006-01-08 01:00:40 -08004833 if (!write || (ret == -EINVAL))
4834 return ret;
Dimitri Sivanich364df0e2009-06-23 12:37:04 -07004835 for_each_populated_zone(zone) {
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09004836 for_each_possible_cpu(cpu) {
Rohit Seth8ad4b1f2006-01-08 01:00:40 -08004837 unsigned long high;
4838 high = zone->present_pages / percpu_pagelist_fraction;
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09004839 setup_pagelist_highmark(
4840 per_cpu_ptr(zone->pageset, cpu), high);
Rohit Seth8ad4b1f2006-01-08 01:00:40 -08004841 }
4842 }
4843 return 0;
4844}
4845
David S. Millerf034b5d2006-08-24 03:08:07 -07004846int hashdist = HASHDIST_DEFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004847
4848#ifdef CONFIG_NUMA
4849static int __init set_hashdist(char *str)
4850{
4851 if (!str)
4852 return 0;
4853 hashdist = simple_strtoul(str, &str, 0);
4854 return 1;
4855}
4856__setup("hashdist=", set_hashdist);
4857#endif
4858
4859/*
4860 * allocate a large system hash table from bootmem
4861 * - it is assumed that the hash table must contain an exact power-of-2
4862 * quantity of entries
4863 * - limit is the number of hash buckets, not the total allocation size
4864 */
4865void *__init alloc_large_system_hash(const char *tablename,
4866 unsigned long bucketsize,
4867 unsigned long numentries,
4868 int scale,
4869 int flags,
4870 unsigned int *_hash_shift,
4871 unsigned int *_hash_mask,
4872 unsigned long limit)
4873{
4874 unsigned long long max = limit;
4875 unsigned long log2qty, size;
4876 void *table = NULL;
4877
4878 /* allow the kernel cmdline to have a say */
4879 if (!numentries) {
4880 /* round applicable memory size up to nearest megabyte */
Andrew Morton04903662006-12-06 20:37:33 -08004881 numentries = nr_kernel_pages;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004882 numentries += (1UL << (20 - PAGE_SHIFT)) - 1;
4883 numentries >>= 20 - PAGE_SHIFT;
4884 numentries <<= 20 - PAGE_SHIFT;
4885
4886 /* limit to 1 bucket per 2^scale bytes of low memory */
4887 if (scale > PAGE_SHIFT)
4888 numentries >>= (scale - PAGE_SHIFT);
4889 else
4890 numentries <<= (PAGE_SHIFT - scale);
Paul Mundt9ab37b82007-01-05 16:36:30 -08004891
4892 /* Make sure we've got at least a 0-order allocation.. */
Jan Beulich2c85f512009-09-21 17:03:07 -07004893 if (unlikely(flags & HASH_SMALL)) {
4894 /* Makes no sense without HASH_EARLY */
4895 WARN_ON(!(flags & HASH_EARLY));
4896 if (!(numentries >> *_hash_shift)) {
4897 numentries = 1UL << *_hash_shift;
4898 BUG_ON(!numentries);
4899 }
4900 } else if (unlikely((numentries * bucketsize) < PAGE_SIZE))
Paul Mundt9ab37b82007-01-05 16:36:30 -08004901 numentries = PAGE_SIZE / bucketsize;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004902 }
John Hawkes6e692ed2006-03-25 03:08:02 -08004903 numentries = roundup_pow_of_two(numentries);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004904
4905 /* limit allocation size to 1/16 total memory by default */
4906 if (max == 0) {
4907 max = ((unsigned long long)nr_all_pages << PAGE_SHIFT) >> 4;
4908 do_div(max, bucketsize);
4909 }
4910
4911 if (numentries > max)
4912 numentries = max;
4913
David Howellsf0d1b0b2006-12-08 02:37:49 -08004914 log2qty = ilog2(numentries);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004915
4916 do {
4917 size = bucketsize << log2qty;
4918 if (flags & HASH_EARLY)
Jan Beulich74768ed2008-08-12 15:08:39 -07004919 table = alloc_bootmem_nopanic(size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004920 else if (hashdist)
4921 table = __vmalloc(size, GFP_ATOMIC, PAGE_KERNEL);
4922 else {
Eric Dumazet1037b832007-07-15 23:38:05 -07004923 /*
4924 * If bucketsize is not a power-of-two, we may free
Mel Gormana1dd2682009-06-16 15:32:19 -07004925 * some pages at the end of hash table which
4926 * alloc_pages_exact() automatically does
Eric Dumazet1037b832007-07-15 23:38:05 -07004927 */
Catalin Marinas264ef8a2009-07-07 10:33:01 +01004928 if (get_order(size) < MAX_ORDER) {
Mel Gormana1dd2682009-06-16 15:32:19 -07004929 table = alloc_pages_exact(size, GFP_ATOMIC);
Catalin Marinas264ef8a2009-07-07 10:33:01 +01004930 kmemleak_alloc(table, size, 1, GFP_ATOMIC);
4931 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07004932 }
4933 } while (!table && size > PAGE_SIZE && --log2qty);
4934
4935 if (!table)
4936 panic("Failed to allocate %s hash table\n", tablename);
4937
Dan Alonib49ad482007-07-15 23:38:23 -07004938 printk(KERN_INFO "%s hash table entries: %d (order: %d, %lu bytes)\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -07004939 tablename,
4940 (1U << log2qty),
David Howellsf0d1b0b2006-12-08 02:37:49 -08004941 ilog2(size) - PAGE_SHIFT,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004942 size);
4943
4944 if (_hash_shift)
4945 *_hash_shift = log2qty;
4946 if (_hash_mask)
4947 *_hash_mask = (1 << log2qty) - 1;
4948
4949 return table;
4950}
KAMEZAWA Hiroyukia117e662006-03-27 01:15:25 -08004951
Mel Gorman835c1342007-10-16 01:25:47 -07004952/* Return a pointer to the bitmap storing bits affecting a block of pages */
4953static inline unsigned long *get_pageblock_bitmap(struct zone *zone,
4954 unsigned long pfn)
4955{
4956#ifdef CONFIG_SPARSEMEM
4957 return __pfn_to_section(pfn)->pageblock_flags;
4958#else
4959 return zone->pageblock_flags;
4960#endif /* CONFIG_SPARSEMEM */
4961}
Andrew Morton6220ec72006-10-19 23:29:05 -07004962
Mel Gorman835c1342007-10-16 01:25:47 -07004963static inline int pfn_to_bitidx(struct zone *zone, unsigned long pfn)
4964{
4965#ifdef CONFIG_SPARSEMEM
4966 pfn &= (PAGES_PER_SECTION-1);
Mel Gormand9c23402007-10-16 01:26:01 -07004967 return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS;
Mel Gorman835c1342007-10-16 01:25:47 -07004968#else
4969 pfn = pfn - zone->zone_start_pfn;
Mel Gormand9c23402007-10-16 01:26:01 -07004970 return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS;
Mel Gorman835c1342007-10-16 01:25:47 -07004971#endif /* CONFIG_SPARSEMEM */
4972}
4973
4974/**
Mel Gormand9c23402007-10-16 01:26:01 -07004975 * 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 -07004976 * @page: The page within the block of interest
4977 * @start_bitidx: The first bit of interest to retrieve
4978 * @end_bitidx: The last bit of interest
4979 * returns pageblock_bits flags
4980 */
4981unsigned long get_pageblock_flags_group(struct page *page,
4982 int start_bitidx, int end_bitidx)
4983{
4984 struct zone *zone;
4985 unsigned long *bitmap;
4986 unsigned long pfn, bitidx;
4987 unsigned long flags = 0;
4988 unsigned long value = 1;
4989
4990 zone = page_zone(page);
4991 pfn = page_to_pfn(page);
4992 bitmap = get_pageblock_bitmap(zone, pfn);
4993 bitidx = pfn_to_bitidx(zone, pfn);
4994
4995 for (; start_bitidx <= end_bitidx; start_bitidx++, value <<= 1)
4996 if (test_bit(bitidx + start_bitidx, bitmap))
4997 flags |= value;
4998
4999 return flags;
5000}
5001
5002/**
Mel Gormand9c23402007-10-16 01:26:01 -07005003 * 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 -07005004 * @page: The page within the block of interest
5005 * @start_bitidx: The first bit of interest
5006 * @end_bitidx: The last bit of interest
5007 * @flags: The flags to set
5008 */
5009void set_pageblock_flags_group(struct page *page, unsigned long flags,
5010 int start_bitidx, int end_bitidx)
5011{
5012 struct zone *zone;
5013 unsigned long *bitmap;
5014 unsigned long pfn, bitidx;
5015 unsigned long value = 1;
5016
5017 zone = page_zone(page);
5018 pfn = page_to_pfn(page);
5019 bitmap = get_pageblock_bitmap(zone, pfn);
5020 bitidx = pfn_to_bitidx(zone, pfn);
KAMEZAWA Hiroyuki86051ca2008-04-29 00:58:21 -07005021 VM_BUG_ON(pfn < zone->zone_start_pfn);
5022 VM_BUG_ON(pfn >= zone->zone_start_pfn + zone->spanned_pages);
Mel Gorman835c1342007-10-16 01:25:47 -07005023
5024 for (; start_bitidx <= end_bitidx; start_bitidx++, value <<= 1)
5025 if (flags & value)
5026 __set_bit(bitidx + start_bitidx, bitmap);
5027 else
5028 __clear_bit(bitidx + start_bitidx, bitmap);
5029}
KAMEZAWA Hiroyukia5d76b52007-10-16 01:26:11 -07005030
5031/*
5032 * This is designed as sub function...plz see page_isolation.c also.
5033 * set/clear page block's type to be ISOLATE.
5034 * page allocater never alloc memory from ISOLATE block.
5035 */
5036
5037int set_migratetype_isolate(struct page *page)
5038{
5039 struct zone *zone;
Robert Jennings925cc712009-12-17 14:44:38 +00005040 struct page *curr_page;
5041 unsigned long flags, pfn, iter;
5042 unsigned long immobile = 0;
5043 struct memory_isolate_notify arg;
5044 int notifier_ret;
KAMEZAWA Hiroyukia5d76b52007-10-16 01:26:11 -07005045 int ret = -EBUSY;
Shaohua Li8e7e40d2009-09-21 17:01:18 -07005046 int zone_idx;
KAMEZAWA Hiroyukia5d76b52007-10-16 01:26:11 -07005047
5048 zone = page_zone(page);
Shaohua Li8e7e40d2009-09-21 17:01:18 -07005049 zone_idx = zone_idx(zone);
Robert Jennings925cc712009-12-17 14:44:38 +00005050
KAMEZAWA Hiroyukia5d76b52007-10-16 01:26:11 -07005051 spin_lock_irqsave(&zone->lock, flags);
Robert Jennings925cc712009-12-17 14:44:38 +00005052 if (get_pageblock_migratetype(page) == MIGRATE_MOVABLE ||
5053 zone_idx == ZONE_MOVABLE) {
5054 ret = 0;
KAMEZAWA Hiroyukia5d76b52007-10-16 01:26:11 -07005055 goto out;
Robert Jennings925cc712009-12-17 14:44:38 +00005056 }
5057
5058 pfn = page_to_pfn(page);
5059 arg.start_pfn = pfn;
5060 arg.nr_pages = pageblock_nr_pages;
5061 arg.pages_found = 0;
5062
5063 /*
5064 * It may be possible to isolate a pageblock even if the
5065 * migratetype is not MIGRATE_MOVABLE. The memory isolation
5066 * notifier chain is used by balloon drivers to return the
5067 * number of pages in a range that are held by the balloon
5068 * driver to shrink memory. If all the pages are accounted for
5069 * by balloons, are free, or on the LRU, isolation can continue.
5070 * Later, for example, when memory hotplug notifier runs, these
5071 * pages reported as "can be isolated" should be isolated(freed)
5072 * by the balloon driver through the memory notifier chain.
5073 */
5074 notifier_ret = memory_isolate_notify(MEM_ISOLATE_COUNT, &arg);
5075 notifier_ret = notifier_to_errno(notifier_ret);
5076 if (notifier_ret || !arg.pages_found)
5077 goto out;
5078
5079 for (iter = pfn; iter < (pfn + pageblock_nr_pages); iter++) {
5080 if (!pfn_valid_within(pfn))
5081 continue;
5082
5083 curr_page = pfn_to_page(iter);
5084 if (!page_count(curr_page) || PageLRU(curr_page))
5085 continue;
5086
5087 immobile++;
5088 }
5089
5090 if (arg.pages_found == immobile)
5091 ret = 0;
5092
KAMEZAWA Hiroyukia5d76b52007-10-16 01:26:11 -07005093out:
Robert Jennings925cc712009-12-17 14:44:38 +00005094 if (!ret) {
5095 set_pageblock_migratetype(page, MIGRATE_ISOLATE);
5096 move_freepages_block(zone, page, MIGRATE_ISOLATE);
5097 }
5098
KAMEZAWA Hiroyukia5d76b52007-10-16 01:26:11 -07005099 spin_unlock_irqrestore(&zone->lock, flags);
5100 if (!ret)
Christoph Lameter9f8f2172008-02-04 22:29:11 -08005101 drain_all_pages();
KAMEZAWA Hiroyukia5d76b52007-10-16 01:26:11 -07005102 return ret;
5103}
5104
5105void unset_migratetype_isolate(struct page *page)
5106{
5107 struct zone *zone;
5108 unsigned long flags;
5109 zone = page_zone(page);
5110 spin_lock_irqsave(&zone->lock, flags);
5111 if (get_pageblock_migratetype(page) != MIGRATE_ISOLATE)
5112 goto out;
5113 set_pageblock_migratetype(page, MIGRATE_MOVABLE);
5114 move_freepages_block(zone, page, MIGRATE_MOVABLE);
5115out:
5116 spin_unlock_irqrestore(&zone->lock, flags);
5117}
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07005118
5119#ifdef CONFIG_MEMORY_HOTREMOVE
5120/*
5121 * All pages in the range must be isolated before calling this.
5122 */
5123void
5124__offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
5125{
5126 struct page *page;
5127 struct zone *zone;
5128 int order, i;
5129 unsigned long pfn;
5130 unsigned long flags;
5131 /* find the first valid pfn */
5132 for (pfn = start_pfn; pfn < end_pfn; pfn++)
5133 if (pfn_valid(pfn))
5134 break;
5135 if (pfn == end_pfn)
5136 return;
5137 zone = page_zone(pfn_to_page(pfn));
5138 spin_lock_irqsave(&zone->lock, flags);
5139 pfn = start_pfn;
5140 while (pfn < end_pfn) {
5141 if (!pfn_valid(pfn)) {
5142 pfn++;
5143 continue;
5144 }
5145 page = pfn_to_page(pfn);
5146 BUG_ON(page_count(page));
5147 BUG_ON(!PageBuddy(page));
5148 order = page_order(page);
5149#ifdef CONFIG_DEBUG_VM
5150 printk(KERN_INFO "remove from free list %lx %d %lx\n",
5151 pfn, 1 << order, end_pfn);
5152#endif
5153 list_del(&page->lru);
5154 rmv_page_order(page);
5155 zone->free_area[order].nr_free--;
5156 __mod_zone_page_state(zone, NR_FREE_PAGES,
5157 - (1UL << order));
5158 for (i = 0; i < (1 << order); i++)
5159 SetPageReserved((page+i));
5160 pfn += (1 << order);
5161 }
5162 spin_unlock_irqrestore(&zone->lock, flags);
5163}
5164#endif
Wu Fengguang8d22ba12009-12-16 12:19:58 +01005165
5166#ifdef CONFIG_MEMORY_FAILURE
5167bool is_free_buddy_page(struct page *page)
5168{
5169 struct zone *zone = page_zone(page);
5170 unsigned long pfn = page_to_pfn(page);
5171 unsigned long flags;
5172 int order;
5173
5174 spin_lock_irqsave(&zone->lock, flags);
5175 for (order = 0; order < MAX_ORDER; order++) {
5176 struct page *page_head = page - (pfn & ((1 << order) - 1));
5177
5178 if (PageBuddy(page_head) && page_order(page_head) >= order)
5179 break;
5180 }
5181 spin_unlock_irqrestore(&zone->lock, flags);
5182
5183 return order < MAX_ORDER;
5184}
5185#endif