blob: 2bc2ac63f41ef8329774a5e444d0be8181ea83bd [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 Rientjes5a3135c2007-10-16 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>
Mel Gorman0d3d0622009-09-21 17:02:44 -070051#include <trace/events/kmem.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070052
53#include <asm/tlbflush.h>
Andrew Mortonac924c62006-05-15 09:43:59 -070054#include <asm/div64.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070055#include "internal.h"
56
57/*
Christoph Lameter13808912007-10-16 01:25:27 -070058 * Array of node states.
Linus Torvalds1da177e2005-04-16 15:20:36 -070059 */
Christoph Lameter13808912007-10-16 01:25:27 -070060nodemask_t node_states[NR_NODE_STATES] __read_mostly = {
61 [N_POSSIBLE] = NODE_MASK_ALL,
62 [N_ONLINE] = { { [0] = 1UL } },
63#ifndef CONFIG_NUMA
64 [N_NORMAL_MEMORY] = { { [0] = 1UL } },
65#ifdef CONFIG_HIGHMEM
66 [N_HIGH_MEMORY] = { { [0] = 1UL } },
67#endif
68 [N_CPU] = { { [0] = 1UL } },
69#endif /* NUMA */
70};
71EXPORT_SYMBOL(node_states);
72
Ravikiran G Thirumalai6c231b72005-09-06 15:17:45 -070073unsigned long totalram_pages __read_mostly;
Hideo AOKIcb45b0e2006-04-10 22:52:59 -070074unsigned long totalreserve_pages __read_mostly;
Rohit Seth8ad4b1f2006-01-08 01:00:40 -080075int percpu_pagelist_fraction;
Benjamin Herrenschmidtdcce2842009-06-18 13:24:12 +100076gfp_t gfp_allowed_mask __read_mostly = GFP_BOOT_MASK;
Linus Torvalds1da177e2005-04-16 15:20:36 -070077
Mel Gormand9c23402007-10-16 01:26:01 -070078#ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
79int pageblock_order __read_mostly;
80#endif
81
Hugh Dickinsd98c7a02006-02-14 13:52:59 -080082static void __free_pages_ok(struct page *page, unsigned int order);
David Howellsa226f6c2006-01-06 00:11:08 -080083
Linus Torvalds1da177e2005-04-16 15:20:36 -070084/*
85 * results with 256, 32 in the lowmem_reserve sysctl:
86 * 1G machine -> (16M dma, 800M-16M normal, 1G-800M high)
87 * 1G machine -> (16M dma, 784M normal, 224M high)
88 * NORMAL allocation will leave 784M/256 of ram reserved in the ZONE_DMA
89 * HIGHMEM allocation will leave 224M/32 of ram reserved in ZONE_NORMAL
90 * HIGHMEM allocation will (224M+784M)/256 of ram reserved in ZONE_DMA
Andi Kleena2f1b422005-11-05 17:25:53 +010091 *
92 * TBD: should special case ZONE_DMA32 machines here - in those we normally
93 * don't need any ZONE_NORMAL reservation
Linus Torvalds1da177e2005-04-16 15:20:36 -070094 */
Christoph Lameter2f1b6242006-09-25 23:31:13 -070095int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES-1] = {
Christoph Lameter4b51d662007-02-10 01:43:10 -080096#ifdef CONFIG_ZONE_DMA
Christoph Lameter2f1b6242006-09-25 23:31:13 -070097 256,
Christoph Lameter4b51d662007-02-10 01:43:10 -080098#endif
Christoph Lameterfb0e7942006-09-25 23:31:13 -070099#ifdef CONFIG_ZONE_DMA32
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700100 256,
Christoph Lameterfb0e7942006-09-25 23:31:13 -0700101#endif
Christoph Lametere53ef382006-09-25 23:31:14 -0700102#ifdef CONFIG_HIGHMEM
Mel Gorman2a1e2742007-07-17 04:03:12 -0700103 32,
Christoph Lametere53ef382006-09-25 23:31:14 -0700104#endif
Mel Gorman2a1e2742007-07-17 04:03:12 -0700105 32,
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700106};
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107
108EXPORT_SYMBOL(totalram_pages);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109
Helge Deller15ad7cd2006-12-06 20:40:36 -0800110static char * const zone_names[MAX_NR_ZONES] = {
Christoph Lameter4b51d662007-02-10 01:43:10 -0800111#ifdef CONFIG_ZONE_DMA
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700112 "DMA",
Christoph Lameter4b51d662007-02-10 01:43:10 -0800113#endif
Christoph Lameterfb0e7942006-09-25 23:31:13 -0700114#ifdef CONFIG_ZONE_DMA32
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700115 "DMA32",
Christoph Lameterfb0e7942006-09-25 23:31:13 -0700116#endif
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700117 "Normal",
Christoph Lametere53ef382006-09-25 23:31:14 -0700118#ifdef CONFIG_HIGHMEM
Mel Gorman2a1e2742007-07-17 04:03:12 -0700119 "HighMem",
Christoph Lametere53ef382006-09-25 23:31:14 -0700120#endif
Mel Gorman2a1e2742007-07-17 04:03:12 -0700121 "Movable",
Christoph Lameter2f1b6242006-09-25 23:31:13 -0700122};
123
Linus Torvalds1da177e2005-04-16 15:20:36 -0700124int min_free_kbytes = 1024;
125
Jan Beulich2c85f512009-09-21 17:03:07 -0700126static unsigned long __meminitdata nr_kernel_pages;
127static unsigned long __meminitdata nr_all_pages;
Yasunori Gotoa3142c82007-05-08 00:23:07 -0700128static unsigned long __meminitdata dma_reserve;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700129
Mel Gormanc7132162006-09-27 01:49:43 -0700130#ifdef CONFIG_ARCH_POPULATES_NODE_MAP
131 /*
Simon Arlott183ff222007-10-20 01:27:18 +0200132 * MAX_ACTIVE_REGIONS determines the maximum number of distinct
Mel Gormanc7132162006-09-27 01:49:43 -0700133 * ranges of memory (RAM) that may be registered with add_active_range().
134 * Ranges passed to add_active_range() will be merged if possible
135 * so the number of times add_active_range() can be called is
136 * related to the number of nodes and the number of holes
137 */
138 #ifdef CONFIG_MAX_ACTIVE_REGIONS
139 /* Allow an architecture to set MAX_ACTIVE_REGIONS to save memory */
140 #define MAX_ACTIVE_REGIONS CONFIG_MAX_ACTIVE_REGIONS
141 #else
142 #if MAX_NUMNODES >= 32
143 /* If there can be many nodes, allow up to 50 holes per node */
144 #define MAX_ACTIVE_REGIONS (MAX_NUMNODES*50)
145 #else
146 /* By default, allow up to 256 distinct regions */
147 #define MAX_ACTIVE_REGIONS 256
148 #endif
149 #endif
150
Jan Beulich98011f52007-07-15 23:38:17 -0700151 static struct node_active_region __meminitdata early_node_map[MAX_ACTIVE_REGIONS];
152 static int __meminitdata nr_nodemap_entries;
153 static unsigned long __meminitdata arch_zone_lowest_possible_pfn[MAX_NR_ZONES];
154 static unsigned long __meminitdata arch_zone_highest_possible_pfn[MAX_NR_ZONES];
Adrian Bunkb69a7282008-07-23 21:28:12 -0700155 static unsigned long __initdata required_kernelcore;
Adrian Bunk484f51f2007-10-16 01:26:03 -0700156 static unsigned long __initdata required_movablecore;
Adrian Bunkb69a7282008-07-23 21:28:12 -0700157 static unsigned long __meminitdata zone_movable_pfn[MAX_NUMNODES];
Mel Gorman2a1e2742007-07-17 04:03:12 -0700158
159 /* movable_zone is the "real" zone pages in ZONE_MOVABLE are taken from */
160 int movable_zone;
161 EXPORT_SYMBOL(movable_zone);
Mel Gormanc7132162006-09-27 01:49:43 -0700162#endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
163
Miklos Szeredi418508c2007-05-23 13:57:55 -0700164#if MAX_NUMNODES > 1
165int nr_node_ids __read_mostly = MAX_NUMNODES;
Christoph Lameter62bc62a2009-06-16 15:32:15 -0700166int nr_online_nodes __read_mostly = 1;
Miklos Szeredi418508c2007-05-23 13:57:55 -0700167EXPORT_SYMBOL(nr_node_ids);
Christoph Lameter62bc62a2009-06-16 15:32:15 -0700168EXPORT_SYMBOL(nr_online_nodes);
Miklos Szeredi418508c2007-05-23 13:57:55 -0700169#endif
170
Mel Gorman9ef9acb2007-10-16 01:25:54 -0700171int page_group_by_mobility_disabled __read_mostly;
172
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700173static void set_pageblock_migratetype(struct page *page, int migratetype)
174{
Mel Gorman49255c62009-06-16 15:31:58 -0700175
176 if (unlikely(page_group_by_mobility_disabled))
177 migratetype = MIGRATE_UNMOVABLE;
178
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700179 set_pageblock_flags_group(page, (unsigned long)migratetype,
180 PB_migrate, PB_migrate_end);
181}
182
Rafael J. Wysocki7f33d492009-06-16 15:32:41 -0700183bool oom_killer_disabled __read_mostly;
184
Nick Piggin13e74442006-01-06 00:10:58 -0800185#ifdef CONFIG_DEBUG_VM
Dave Hansenc6a57e12005-10-29 18:16:52 -0700186static int page_outside_zone_boundaries(struct zone *zone, struct page *page)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700187{
Dave Hansenbdc8cb92005-10-29 18:16:53 -0700188 int ret = 0;
189 unsigned seq;
190 unsigned long pfn = page_to_pfn(page);
Dave Hansenc6a57e12005-10-29 18:16:52 -0700191
Dave Hansenbdc8cb92005-10-29 18:16:53 -0700192 do {
193 seq = zone_span_seqbegin(zone);
194 if (pfn >= zone->zone_start_pfn + zone->spanned_pages)
195 ret = 1;
196 else if (pfn < zone->zone_start_pfn)
197 ret = 1;
198 } while (zone_span_seqretry(zone, seq));
199
200 return ret;
Dave Hansenc6a57e12005-10-29 18:16:52 -0700201}
202
203static int page_is_consistent(struct zone *zone, struct page *page)
204{
Andy Whitcroft14e07292007-05-06 14:49:14 -0700205 if (!pfn_valid_within(page_to_pfn(page)))
Dave Hansenc6a57e12005-10-29 18:16:52 -0700206 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700207 if (zone != page_zone(page))
Dave Hansenc6a57e12005-10-29 18:16:52 -0700208 return 0;
209
210 return 1;
211}
212/*
213 * Temporary debugging check for pages not lying within a given zone.
214 */
215static int bad_range(struct zone *zone, struct page *page)
216{
217 if (page_outside_zone_boundaries(zone, page))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700218 return 1;
Dave Hansenc6a57e12005-10-29 18:16:52 -0700219 if (!page_is_consistent(zone, page))
220 return 1;
221
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222 return 0;
223}
Nick Piggin13e74442006-01-06 00:10:58 -0800224#else
225static inline int bad_range(struct zone *zone, struct page *page)
226{
227 return 0;
228}
229#endif
230
Nick Piggin224abf92006-01-06 00:11:11 -0800231static void bad_page(struct page *page)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700232{
Hugh Dickinsd936cf92009-01-06 14:40:12 -0800233 static unsigned long resume;
234 static unsigned long nr_shown;
235 static unsigned long nr_unshown;
236
Wu Fengguang2a7684a2009-09-16 11:50:12 +0200237 /* Don't complain about poisoned pages */
238 if (PageHWPoison(page)) {
239 __ClearPageBuddy(page);
240 return;
241 }
242
Hugh Dickinsd936cf92009-01-06 14:40:12 -0800243 /*
244 * Allow a burst of 60 reports, then keep quiet for that minute;
245 * or allow a steady drip of one report per second.
246 */
247 if (nr_shown == 60) {
248 if (time_before(jiffies, resume)) {
249 nr_unshown++;
250 goto out;
251 }
252 if (nr_unshown) {
Hugh Dickins1e9e6362009-01-06 14:40:13 -0800253 printk(KERN_ALERT
254 "BUG: Bad page state: %lu messages suppressed\n",
Hugh Dickinsd936cf92009-01-06 14:40:12 -0800255 nr_unshown);
256 nr_unshown = 0;
257 }
258 nr_shown = 0;
259 }
260 if (nr_shown++ == 0)
261 resume = jiffies + 60 * HZ;
262
Hugh Dickins1e9e6362009-01-06 14:40:13 -0800263 printk(KERN_ALERT "BUG: Bad page state in process %s pfn:%05lx\n",
Hugh Dickins3dc14742009-01-06 14:40:08 -0800264 current->comm, page_to_pfn(page));
Hugh Dickins1e9e6362009-01-06 14:40:13 -0800265 printk(KERN_ALERT
Hugh Dickins3dc14742009-01-06 14:40:08 -0800266 "page:%p flags:%p count:%d mapcount:%d mapping:%p index:%lx\n",
267 page, (void *)page->flags, page_count(page),
268 page_mapcount(page), page->mapping, page->index);
KAMEZAWA Hiroyuki52d4b9a2008-10-18 20:28:16 -0700269
Linus Torvalds1da177e2005-04-16 15:20:36 -0700270 dump_stack();
Hugh Dickinsd936cf92009-01-06 14:40:12 -0800271out:
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800272 /* Leave bad fields for debug, except PageBuddy could make trouble */
273 __ClearPageBuddy(page);
Randy Dunlap9f158332005-09-13 01:25:16 -0700274 add_taint(TAINT_BAD_PAGE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700275}
276
Linus Torvalds1da177e2005-04-16 15:20:36 -0700277/*
278 * Higher-order pages are called "compound pages". They are structured thusly:
279 *
280 * The first PAGE_SIZE page is called the "head page".
281 *
282 * The remaining PAGE_SIZE pages are called "tail pages".
283 *
284 * All pages have PG_compound set. All pages have their ->private pointing at
285 * the head page (even the head page has this).
286 *
Hugh Dickins41d78ba2006-02-14 13:52:58 -0800287 * The first tail page's ->lru.next holds the address of the compound page's
288 * put_page() function. Its ->lru.prev holds the order of allocation.
289 * This usage means that zero-order pages may not be compound.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290 */
Hugh Dickinsd98c7a02006-02-14 13:52:59 -0800291
292static void free_compound_page(struct page *page)
293{
Christoph Lameterd85f3382007-05-06 14:49:39 -0700294 __free_pages_ok(page, compound_order(page));
Hugh Dickinsd98c7a02006-02-14 13:52:59 -0800295}
296
Andi Kleen01ad1c02008-07-23 21:27:46 -0700297void prep_compound_page(struct page *page, unsigned long order)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700298{
299 int i;
300 int nr_pages = 1 << order;
301
Andy Whitcroft33f2ef82006-12-06 20:33:32 -0800302 set_compound_page_dtor(page, free_compound_page);
Christoph Lameterd85f3382007-05-06 14:49:39 -0700303 set_compound_order(page, order);
Christoph Lameter6d777952007-05-06 14:49:40 -0700304 __SetPageHead(page);
Andy Whitcroft18229df2008-11-06 12:53:27 -0800305 for (i = 1; i < nr_pages; i++) {
306 struct page *p = page + i;
307
Christoph Lameterd85f3382007-05-06 14:49:39 -0700308 __SetPageTail(p);
Christoph Lameterd85f3382007-05-06 14:49:39 -0700309 p->first_page = page;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700310 }
311}
312
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800313static int destroy_compound_page(struct page *page, unsigned long order)
Andy Whitcroft18229df2008-11-06 12:53:27 -0800314{
315 int i;
316 int nr_pages = 1 << order;
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800317 int bad = 0;
Andy Whitcroft18229df2008-11-06 12:53:27 -0800318
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800319 if (unlikely(compound_order(page) != order) ||
320 unlikely(!PageHead(page))) {
Nick Piggin224abf92006-01-06 00:11:11 -0800321 bad_page(page);
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800322 bad++;
323 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700324
Christoph Lameter6d777952007-05-06 14:49:40 -0700325 __ClearPageHead(page);
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800326
Andy Whitcroft18229df2008-11-06 12:53:27 -0800327 for (i = 1; i < nr_pages; i++) {
328 struct page *p = page + i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700329
Alexey Zaytseve713a212009-01-10 02:47:57 +0300330 if (unlikely(!PageTail(p) || (p->first_page != page))) {
Nick Piggin224abf92006-01-06 00:11:11 -0800331 bad_page(page);
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800332 bad++;
333 }
Christoph Lameterd85f3382007-05-06 14:49:39 -0700334 __ClearPageTail(p);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700335 }
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800336
337 return bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700339
Nick Piggin17cf4402006-03-22 00:08:41 -0800340static inline void prep_zero_page(struct page *page, int order, gfp_t gfp_flags)
341{
342 int i;
343
Andrew Morton6626c5d2006-03-22 00:08:42 -0800344 /*
345 * clear_highpage() will use KM_USER0, so it's a bug to use __GFP_ZERO
346 * and __GFP_HIGHMEM from hard or soft interrupt context.
347 */
Nick Piggin725d7042006-09-25 23:30:55 -0700348 VM_BUG_ON((gfp_flags & __GFP_HIGHMEM) && in_interrupt());
Nick Piggin17cf4402006-03-22 00:08:41 -0800349 for (i = 0; i < (1 << order); i++)
350 clear_highpage(page + i);
351}
352
Andrew Morton6aa30012006-04-18 22:20:52 -0700353static inline void set_page_order(struct page *page, int order)
354{
Hugh Dickins4c21e2f2005-10-29 18:16:40 -0700355 set_page_private(page, order);
Nick Piggin676165a2006-04-10 11:21:48 +1000356 __SetPageBuddy(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700357}
358
359static inline void rmv_page_order(struct page *page)
360{
Nick Piggin676165a2006-04-10 11:21:48 +1000361 __ClearPageBuddy(page);
Hugh Dickins4c21e2f2005-10-29 18:16:40 -0700362 set_page_private(page, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700363}
364
365/*
366 * Locate the struct page for both the matching buddy in our
367 * pair (buddy1) and the combined O(n+1) page they form (page).
368 *
369 * 1) Any buddy B1 will have an order O twin B2 which satisfies
370 * the following equation:
371 * B2 = B1 ^ (1 << O)
372 * For example, if the starting buddy (buddy2) is #8 its order
373 * 1 buddy is #10:
374 * B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10
375 *
376 * 2) Any buddy B will have an order O+1 parent P which
377 * satisfies the following equation:
378 * P = B & ~(1 << O)
379 *
Andreas Mohrd6e05ed2006-06-26 18:35:02 +0200380 * Assumption: *_mem_map is contiguous at least up to MAX_ORDER
Linus Torvalds1da177e2005-04-16 15:20:36 -0700381 */
382static inline struct page *
383__page_find_buddy(struct page *page, unsigned long page_idx, unsigned int order)
384{
385 unsigned long buddy_idx = page_idx ^ (1 << order);
386
387 return page + (buddy_idx - page_idx);
388}
389
390static inline unsigned long
391__find_combined_index(unsigned long page_idx, unsigned int order)
392{
393 return (page_idx & ~(1 << order));
394}
395
396/*
397 * This function checks whether a page is free && is the buddy
398 * we can do coalesce a page and its buddy if
Nick Piggin13e74442006-01-06 00:10:58 -0800399 * (a) the buddy is not in a hole &&
Nick Piggin676165a2006-04-10 11:21:48 +1000400 * (b) the buddy is in the buddy system &&
Andy Whitcroftcb2b95e2006-06-23 02:03:01 -0700401 * (c) a page and its buddy have the same order &&
402 * (d) a page and its buddy are in the same zone.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700403 *
Nick Piggin676165a2006-04-10 11:21:48 +1000404 * For recording whether a page is in the buddy system, we use PG_buddy.
405 * Setting, clearing, and testing PG_buddy is serialized by zone->lock.
406 *
407 * For recording page's order, we use page_private(page).
Linus Torvalds1da177e2005-04-16 15:20:36 -0700408 */
Andy Whitcroftcb2b95e2006-06-23 02:03:01 -0700409static inline int page_is_buddy(struct page *page, struct page *buddy,
410 int order)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700411{
Andy Whitcroft14e07292007-05-06 14:49:14 -0700412 if (!pfn_valid_within(page_to_pfn(buddy)))
Nick Piggin13e74442006-01-06 00:10:58 -0800413 return 0;
Nick Piggin13e74442006-01-06 00:10:58 -0800414
Andy Whitcroftcb2b95e2006-06-23 02:03:01 -0700415 if (page_zone_id(page) != page_zone_id(buddy))
416 return 0;
417
418 if (PageBuddy(buddy) && page_order(buddy) == order) {
Nick Piggina3af9c32009-06-16 15:32:10 -0700419 VM_BUG_ON(page_count(buddy) != 0);
Andrew Morton6aa30012006-04-18 22:20:52 -0700420 return 1;
Nick Piggin676165a2006-04-10 11:21:48 +1000421 }
Andrew Morton6aa30012006-04-18 22:20:52 -0700422 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700423}
424
425/*
426 * Freeing function for a buddy system allocator.
427 *
428 * The concept of a buddy system is to maintain direct-mapped table
429 * (containing bit values) for memory blocks of various "orders".
430 * The bottom level table contains the map for the smallest allocatable
431 * units of memory (here, pages), and each level above it describes
432 * pairs of units from the levels below, hence, "buddies".
433 * At a high level, all that happens here is marking the table entry
434 * at the bottom level available, and propagating the changes upward
435 * as necessary, plus some accounting needed to play nicely with other
436 * parts of the VM system.
437 * At each level, we keep a list of pages, which are heads of continuous
Nick Piggin676165a2006-04-10 11:21:48 +1000438 * free pages of length of (1 << order) and marked with PG_buddy. Page's
Hugh Dickins4c21e2f2005-10-29 18:16:40 -0700439 * order is recorded in page_private(page) field.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700440 * So when we are allocating or freeing one, we can derive the state of the
441 * other. That is, if we allocate a small block, and both were
442 * free, the remainder of the region must be split into blocks.
443 * If a block is freed, and its buddy is also free, then this
444 * triggers coalescing into a block of larger size.
445 *
446 * -- wli
447 */
448
Nick Piggin48db57f2006-01-08 01:00:42 -0800449static inline void __free_one_page(struct page *page,
Mel Gormaned0ae212009-06-16 15:32:07 -0700450 struct zone *zone, unsigned int order,
451 int migratetype)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700452{
453 unsigned long page_idx;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700454
Nick Piggin224abf92006-01-06 00:11:11 -0800455 if (unlikely(PageCompound(page)))
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800456 if (unlikely(destroy_compound_page(page, order)))
457 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700458
Mel Gormaned0ae212009-06-16 15:32:07 -0700459 VM_BUG_ON(migratetype == -1);
460
Linus Torvalds1da177e2005-04-16 15:20:36 -0700461 page_idx = page_to_pfn(page) & ((1 << MAX_ORDER) - 1);
462
Mel Gormanf2260e62009-06-16 15:32:13 -0700463 VM_BUG_ON(page_idx & ((1 << order) - 1));
Nick Piggin725d7042006-09-25 23:30:55 -0700464 VM_BUG_ON(bad_range(zone, page));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700465
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466 while (order < MAX_ORDER-1) {
467 unsigned long combined_idx;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700468 struct page *buddy;
469
Linus Torvalds1da177e2005-04-16 15:20:36 -0700470 buddy = __page_find_buddy(page, page_idx, order);
Andy Whitcroftcb2b95e2006-06-23 02:03:01 -0700471 if (!page_is_buddy(page, buddy, order))
Andy Whitcroft3c82d0c2008-07-23 21:27:11 -0700472 break;
Nick Piggin13e74442006-01-06 00:10:58 -0800473
Andy Whitcroft3c82d0c2008-07-23 21:27:11 -0700474 /* Our buddy is free, merge with it and move up one order. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700475 list_del(&buddy->lru);
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700476 zone->free_area[order].nr_free--;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700477 rmv_page_order(buddy);
Nick Piggin13e74442006-01-06 00:10:58 -0800478 combined_idx = __find_combined_index(page_idx, order);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700479 page = page + (combined_idx - page_idx);
480 page_idx = combined_idx;
481 order++;
482 }
483 set_page_order(page, order);
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700484 list_add(&page->lru,
485 &zone->free_area[order].free_list[migratetype]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700486 zone->free_area[order].nr_free++;
487}
488
KOSAKI Motohiro092cead2009-06-16 15:32:17 -0700489#ifdef CONFIG_HAVE_MLOCKED_PAGE_BIT
490/*
491 * free_page_mlock() -- clean up attempts to free and mlocked() page.
492 * Page should not be on lru, so no need to fix that up.
493 * free_pages_check() will verify...
494 */
495static inline void free_page_mlock(struct page *page)
496{
KOSAKI Motohiro092cead2009-06-16 15:32:17 -0700497 __dec_zone_page_state(page, NR_MLOCK);
498 __count_vm_event(UNEVICTABLE_MLOCKFREED);
499}
500#else
501static void free_page_mlock(struct page *page) { }
502#endif
503
Nick Piggin224abf92006-01-06 00:11:11 -0800504static inline int free_pages_check(struct page *page)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700505{
Nick Piggin92be2e32006-01-06 00:10:57 -0800506 if (unlikely(page_mapcount(page) |
507 (page->mapping != NULL) |
Nick Piggina3af9c32009-06-16 15:32:10 -0700508 (atomic_read(&page->_count) != 0) |
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800509 (page->flags & PAGE_FLAGS_CHECK_AT_FREE))) {
Nick Piggin224abf92006-01-06 00:11:11 -0800510 bad_page(page);
Hugh Dickins79f4b7b2009-01-06 14:40:05 -0800511 return 1;
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800512 }
Hugh Dickins79f4b7b2009-01-06 14:40:05 -0800513 if (page->flags & PAGE_FLAGS_CHECK_AT_PREP)
514 page->flags &= ~PAGE_FLAGS_CHECK_AT_PREP;
515 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700516}
517
518/*
Mel Gorman5f8dcc22009-09-21 17:03:19 -0700519 * Frees a number of pages from the PCP lists
Linus Torvalds1da177e2005-04-16 15:20:36 -0700520 * Assumes all pages on list are in same zone, and of same order.
Renaud Lienhart207f36e2005-09-10 00:26:59 -0700521 * count is the number of pages to free.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700522 *
523 * If the zone was previously in an "all pages pinned" state then look to
524 * see if this freeing clears that state.
525 *
526 * And clear the zone's pages_scanned counter, to hold off the "all pages are
527 * pinned" detection logic.
528 */
Mel Gorman5f8dcc22009-09-21 17:03:19 -0700529static void free_pcppages_bulk(struct zone *zone, int count,
530 struct per_cpu_pages *pcp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700531{
Mel Gorman5f8dcc22009-09-21 17:03:19 -0700532 int migratetype = 0;
Mel Gormana6f9edd2009-09-21 17:03:20 -0700533 int batch_free = 0;
Mel Gorman5f8dcc22009-09-21 17:03:19 -0700534
Nick Pigginc54ad302006-01-06 00:10:56 -0800535 spin_lock(&zone->lock);
David Rientjese815af92007-10-16 23:25:54 -0700536 zone_clear_flag(zone, ZONE_ALL_UNRECLAIMABLE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700537 zone->pages_scanned = 0;
Mel Gormanf2260e62009-06-16 15:32:13 -0700538
Mel Gorman5f8dcc22009-09-21 17:03:19 -0700539 __mod_zone_page_state(zone, NR_FREE_PAGES, count);
Mel Gormana6f9edd2009-09-21 17:03:20 -0700540 while (count) {
Nick Piggin48db57f2006-01-08 01:00:42 -0800541 struct page *page;
Mel Gorman5f8dcc22009-09-21 17:03:19 -0700542 struct list_head *list;
Nick Piggin48db57f2006-01-08 01:00:42 -0800543
Mel Gorman5f8dcc22009-09-21 17:03:19 -0700544 /*
Mel Gormana6f9edd2009-09-21 17:03:20 -0700545 * Remove pages from lists in a round-robin fashion. A
546 * batch_free count is maintained that is incremented when an
547 * empty list is encountered. This is so more pages are freed
548 * off fuller lists instead of spinning excessively around empty
549 * lists
Mel Gorman5f8dcc22009-09-21 17:03:19 -0700550 */
551 do {
Mel Gormana6f9edd2009-09-21 17:03:20 -0700552 batch_free++;
Mel Gorman5f8dcc22009-09-21 17:03:19 -0700553 if (++migratetype == MIGRATE_PCPTYPES)
554 migratetype = 0;
555 list = &pcp->lists[migratetype];
556 } while (list_empty(list));
557
Mel Gormana6f9edd2009-09-21 17:03:20 -0700558 do {
559 page = list_entry(list->prev, struct page, lru);
560 /* must delete as __free_one_page list manipulates */
561 list_del(&page->lru);
562 __free_one_page(page, zone, 0, migratetype);
563 trace_mm_page_pcpu_drain(page, 0, migratetype);
564 } while (--count && --batch_free && !list_empty(list));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700565 }
Nick Pigginc54ad302006-01-06 00:10:56 -0800566 spin_unlock(&zone->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700567}
568
Mel Gormaned0ae212009-06-16 15:32:07 -0700569static void free_one_page(struct zone *zone, struct page *page, int order,
570 int migratetype)
Nick Piggin48db57f2006-01-08 01:00:42 -0800571{
Christoph Lameter006d22d2006-09-25 23:31:48 -0700572 spin_lock(&zone->lock);
David Rientjese815af92007-10-16 23:25:54 -0700573 zone_clear_flag(zone, ZONE_ALL_UNRECLAIMABLE);
Christoph Lameter006d22d2006-09-25 23:31:48 -0700574 zone->pages_scanned = 0;
Mel Gormanf2260e62009-06-16 15:32:13 -0700575
576 __mod_zone_page_state(zone, NR_FREE_PAGES, 1 << order);
Mel Gormaned0ae212009-06-16 15:32:07 -0700577 __free_one_page(page, zone, order, migratetype);
Christoph Lameter006d22d2006-09-25 23:31:48 -0700578 spin_unlock(&zone->lock);
Nick Piggin48db57f2006-01-08 01:00:42 -0800579}
580
581static void __free_pages_ok(struct page *page, unsigned int order)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700582{
Nick Pigginc54ad302006-01-06 00:10:56 -0800583 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700584 int i;
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800585 int bad = 0;
Johannes Weiner451ea252009-09-21 17:01:48 -0700586 int wasMlocked = __TestClearPageMlocked(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700587
Vegard Nossumb1eeab62008-11-25 16:55:53 +0100588 kmemcheck_free_shadow(page, order);
589
Linus Torvalds1da177e2005-04-16 15:20:36 -0700590 for (i = 0 ; i < (1 << order) ; ++i)
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800591 bad += free_pages_check(page + i);
592 if (bad)
Hugh Dickins689bceb2005-11-21 21:32:20 -0800593 return;
594
Thomas Gleixner3ac7fe52008-04-30 00:55:01 -0700595 if (!PageHighMem(page)) {
Nick Piggin9858db52006-10-11 01:21:30 -0700596 debug_check_no_locks_freed(page_address(page),PAGE_SIZE<<order);
Thomas Gleixner3ac7fe52008-04-30 00:55:01 -0700597 debug_check_no_obj_freed(page_address(page),
598 PAGE_SIZE << order);
599 }
Nick Piggindafb1362006-10-11 01:21:30 -0700600 arch_free_page(page, order);
Nick Piggin48db57f2006-01-08 01:00:42 -0800601 kernel_map_pages(page, 1 << order, 0);
Nick Piggindafb1362006-10-11 01:21:30 -0700602
Nick Pigginc54ad302006-01-06 00:10:56 -0800603 local_irq_save(flags);
Johannes Weinerc2773312009-06-19 19:30:56 +0200604 if (unlikely(wasMlocked))
Mel Gormanda456f12009-06-16 15:32:08 -0700605 free_page_mlock(page);
Christoph Lameterf8891e52006-06-30 01:55:45 -0700606 __count_vm_events(PGFREE, 1 << order);
Mel Gormaned0ae212009-06-16 15:32:07 -0700607 free_one_page(page_zone(page), page, order,
608 get_pageblock_migratetype(page));
Nick Pigginc54ad302006-01-06 00:10:56 -0800609 local_irq_restore(flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700610}
611
David Howellsa226f6c2006-01-06 00:11:08 -0800612/*
613 * permit the bootmem allocator to evade page validation on high-order frees
614 */
Yasunori Gotoaf370fb2008-07-23 21:28:17 -0700615void __meminit __free_pages_bootmem(struct page *page, unsigned int order)
David Howellsa226f6c2006-01-06 00:11:08 -0800616{
617 if (order == 0) {
618 __ClearPageReserved(page);
619 set_page_count(page, 0);
Nick Piggin7835e982006-03-22 00:08:40 -0800620 set_page_refcounted(page);
Nick Piggin545b1ea2006-03-22 00:08:07 -0800621 __free_page(page);
David Howellsa226f6c2006-01-06 00:11:08 -0800622 } else {
David Howellsa226f6c2006-01-06 00:11:08 -0800623 int loop;
624
Nick Piggin545b1ea2006-03-22 00:08:07 -0800625 prefetchw(page);
David Howellsa226f6c2006-01-06 00:11:08 -0800626 for (loop = 0; loop < BITS_PER_LONG; loop++) {
627 struct page *p = &page[loop];
628
Nick Piggin545b1ea2006-03-22 00:08:07 -0800629 if (loop + 1 < BITS_PER_LONG)
630 prefetchw(p + 1);
David Howellsa226f6c2006-01-06 00:11:08 -0800631 __ClearPageReserved(p);
632 set_page_count(p, 0);
633 }
634
Nick Piggin7835e982006-03-22 00:08:40 -0800635 set_page_refcounted(page);
Nick Piggin545b1ea2006-03-22 00:08:07 -0800636 __free_pages(page, order);
David Howellsa226f6c2006-01-06 00:11:08 -0800637 }
638}
639
Linus Torvalds1da177e2005-04-16 15:20:36 -0700640
641/*
642 * The order of subdivision here is critical for the IO subsystem.
643 * Please do not alter this order without good reasons and regression
644 * testing. Specifically, as large blocks of memory are subdivided,
645 * the order in which smaller blocks are delivered depends on the order
646 * they're subdivided in this function. This is the primary factor
647 * influencing the order in which pages are delivered to the IO
648 * subsystem according to empirical testing, and this is also justified
649 * by considering the behavior of a buddy system containing a single
650 * large block of memory acted on by a series of small allocations.
651 * This behavior is a critical factor in sglist merging's success.
652 *
653 * -- wli
654 */
Nick Piggin085cc7d2006-01-06 00:11:01 -0800655static inline void expand(struct zone *zone, struct page *page,
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700656 int low, int high, struct free_area *area,
657 int migratetype)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700658{
659 unsigned long size = 1 << high;
660
661 while (high > low) {
662 area--;
663 high--;
664 size >>= 1;
Nick Piggin725d7042006-09-25 23:30:55 -0700665 VM_BUG_ON(bad_range(zone, &page[size]));
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700666 list_add(&page[size].lru, &area->free_list[migratetype]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700667 area->nr_free++;
668 set_page_order(&page[size], high);
669 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700670}
671
Linus Torvalds1da177e2005-04-16 15:20:36 -0700672/*
673 * This page is about to be returned from the page allocator
674 */
Wu Fengguang2a7684a2009-09-16 11:50:12 +0200675static inline int check_new_page(struct page *page)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700676{
Nick Piggin92be2e32006-01-06 00:10:57 -0800677 if (unlikely(page_mapcount(page) |
678 (page->mapping != NULL) |
Nick Piggina3af9c32009-06-16 15:32:10 -0700679 (atomic_read(&page->_count) != 0) |
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800680 (page->flags & PAGE_FLAGS_CHECK_AT_PREP))) {
Nick Piggin224abf92006-01-06 00:11:11 -0800681 bad_page(page);
Hugh Dickins689bceb2005-11-21 21:32:20 -0800682 return 1;
Hugh Dickins8cc3b392009-01-06 14:40:06 -0800683 }
Wu Fengguang2a7684a2009-09-16 11:50:12 +0200684 return 0;
685}
686
687static int prep_new_page(struct page *page, int order, gfp_t gfp_flags)
688{
689 int i;
690
691 for (i = 0; i < (1 << order); i++) {
692 struct page *p = page + i;
693 if (unlikely(check_new_page(p)))
694 return 1;
695 }
Hugh Dickins689bceb2005-11-21 21:32:20 -0800696
Hugh Dickins4c21e2f2005-10-29 18:16:40 -0700697 set_page_private(page, 0);
Nick Piggin7835e982006-03-22 00:08:40 -0800698 set_page_refcounted(page);
Nick Piggincc102502006-12-06 20:32:00 -0800699
700 arch_alloc_page(page, order);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700701 kernel_map_pages(page, 1 << order, 1);
Nick Piggin17cf4402006-03-22 00:08:41 -0800702
703 if (gfp_flags & __GFP_ZERO)
704 prep_zero_page(page, order, gfp_flags);
705
706 if (order && (gfp_flags & __GFP_COMP))
707 prep_compound_page(page, order);
708
Hugh Dickins689bceb2005-11-21 21:32:20 -0800709 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700710}
711
Mel Gorman56fd56b2007-10-16 01:25:58 -0700712/*
713 * Go through the free lists for the given migratetype and remove
714 * the smallest available page from the freelists
715 */
Mel Gorman728ec982009-06-16 15:32:04 -0700716static inline
717struct page *__rmqueue_smallest(struct zone *zone, unsigned int order,
Mel Gorman56fd56b2007-10-16 01:25:58 -0700718 int migratetype)
719{
720 unsigned int current_order;
721 struct free_area * area;
722 struct page *page;
723
724 /* Find a page of the appropriate size in the preferred list */
725 for (current_order = order; current_order < MAX_ORDER; ++current_order) {
726 area = &(zone->free_area[current_order]);
727 if (list_empty(&area->free_list[migratetype]))
728 continue;
729
730 page = list_entry(area->free_list[migratetype].next,
731 struct page, lru);
732 list_del(&page->lru);
733 rmv_page_order(page);
734 area->nr_free--;
Mel Gorman56fd56b2007-10-16 01:25:58 -0700735 expand(zone, page, order, current_order, area, migratetype);
736 return page;
737 }
738
739 return NULL;
740}
741
742
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700743/*
744 * This array describes the order lists are fallen back to when
745 * the free lists for the desirable migrate type are depleted
746 */
747static int fallbacks[MIGRATE_TYPES][MIGRATE_TYPES-1] = {
Mel Gorman64c5e132007-10-16 01:25:59 -0700748 [MIGRATE_UNMOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_MOVABLE, MIGRATE_RESERVE },
749 [MIGRATE_RECLAIMABLE] = { MIGRATE_UNMOVABLE, MIGRATE_MOVABLE, MIGRATE_RESERVE },
750 [MIGRATE_MOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE, MIGRATE_RESERVE },
751 [MIGRATE_RESERVE] = { MIGRATE_RESERVE, MIGRATE_RESERVE, MIGRATE_RESERVE }, /* Never used */
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700752};
753
Mel Gormanc361be52007-10-16 01:25:51 -0700754/*
755 * Move the free pages in a range to the free lists of the requested type.
Mel Gormand9c23402007-10-16 01:26:01 -0700756 * Note that start_page and end_pages are not aligned on a pageblock
Mel Gormanc361be52007-10-16 01:25:51 -0700757 * boundary. If alignment is required, use move_freepages_block()
758 */
Adrian Bunkb69a7282008-07-23 21:28:12 -0700759static int move_freepages(struct zone *zone,
760 struct page *start_page, struct page *end_page,
761 int migratetype)
Mel Gormanc361be52007-10-16 01:25:51 -0700762{
763 struct page *page;
764 unsigned long order;
Mel Gormand1003132007-10-16 01:26:00 -0700765 int pages_moved = 0;
Mel Gormanc361be52007-10-16 01:25:51 -0700766
767#ifndef CONFIG_HOLES_IN_ZONE
768 /*
769 * page_zone is not safe to call in this context when
770 * CONFIG_HOLES_IN_ZONE is set. This bug check is probably redundant
771 * anyway as we check zone boundaries in move_freepages_block().
772 * Remove at a later date when no bug reports exist related to
Mel Gormanac0e5b72007-10-16 01:25:58 -0700773 * grouping pages by mobility
Mel Gormanc361be52007-10-16 01:25:51 -0700774 */
775 BUG_ON(page_zone(start_page) != page_zone(end_page));
776#endif
777
778 for (page = start_page; page <= end_page;) {
Adam Litke344c7902008-09-02 14:35:38 -0700779 /* Make sure we are not inadvertently changing nodes */
780 VM_BUG_ON(page_to_nid(page) != zone_to_nid(zone));
781
Mel Gormanc361be52007-10-16 01:25:51 -0700782 if (!pfn_valid_within(page_to_pfn(page))) {
783 page++;
784 continue;
785 }
786
787 if (!PageBuddy(page)) {
788 page++;
789 continue;
790 }
791
792 order = page_order(page);
793 list_del(&page->lru);
794 list_add(&page->lru,
795 &zone->free_area[order].free_list[migratetype]);
796 page += 1 << order;
Mel Gormand1003132007-10-16 01:26:00 -0700797 pages_moved += 1 << order;
Mel Gormanc361be52007-10-16 01:25:51 -0700798 }
799
Mel Gormand1003132007-10-16 01:26:00 -0700800 return pages_moved;
Mel Gormanc361be52007-10-16 01:25:51 -0700801}
802
Adrian Bunkb69a7282008-07-23 21:28:12 -0700803static int move_freepages_block(struct zone *zone, struct page *page,
804 int migratetype)
Mel Gormanc361be52007-10-16 01:25:51 -0700805{
806 unsigned long start_pfn, end_pfn;
807 struct page *start_page, *end_page;
808
809 start_pfn = page_to_pfn(page);
Mel Gormand9c23402007-10-16 01:26:01 -0700810 start_pfn = start_pfn & ~(pageblock_nr_pages-1);
Mel Gormanc361be52007-10-16 01:25:51 -0700811 start_page = pfn_to_page(start_pfn);
Mel Gormand9c23402007-10-16 01:26:01 -0700812 end_page = start_page + pageblock_nr_pages - 1;
813 end_pfn = start_pfn + pageblock_nr_pages - 1;
Mel Gormanc361be52007-10-16 01:25:51 -0700814
815 /* Do not cross zone boundaries */
816 if (start_pfn < zone->zone_start_pfn)
817 start_page = page;
818 if (end_pfn >= zone->zone_start_pfn + zone->spanned_pages)
819 return 0;
820
821 return move_freepages(zone, start_page, end_page, migratetype);
822}
823
Mel Gorman2f66a682009-09-21 17:02:31 -0700824static void change_pageblock_range(struct page *pageblock_page,
825 int start_order, int migratetype)
826{
827 int nr_pageblocks = 1 << (start_order - pageblock_order);
828
829 while (nr_pageblocks--) {
830 set_pageblock_migratetype(pageblock_page, migratetype);
831 pageblock_page += pageblock_nr_pages;
832 }
833}
834
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700835/* Remove an element from the buddy allocator from the fallback list */
Mel Gorman0ac3a402009-06-16 15:32:06 -0700836static inline struct page *
837__rmqueue_fallback(struct zone *zone, int order, int start_migratetype)
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700838{
839 struct free_area * area;
840 int current_order;
841 struct page *page;
842 int migratetype, i;
843
844 /* Find the largest possible block of pages in the other list */
845 for (current_order = MAX_ORDER-1; current_order >= order;
846 --current_order) {
847 for (i = 0; i < MIGRATE_TYPES - 1; i++) {
848 migratetype = fallbacks[start_migratetype][i];
849
Mel Gorman56fd56b2007-10-16 01:25:58 -0700850 /* MIGRATE_RESERVE handled later if necessary */
851 if (migratetype == MIGRATE_RESERVE)
852 continue;
Mel Gormane0104872007-10-16 01:25:53 -0700853
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700854 area = &(zone->free_area[current_order]);
855 if (list_empty(&area->free_list[migratetype]))
856 continue;
857
858 page = list_entry(area->free_list[migratetype].next,
859 struct page, lru);
860 area->nr_free--;
861
862 /*
Mel Gormanc361be52007-10-16 01:25:51 -0700863 * If breaking a large block of pages, move all free
Mel Gorman46dafbc2007-10-16 01:25:55 -0700864 * pages to the preferred allocation list. If falling
865 * back for a reclaimable kernel allocation, be more
866 * agressive about taking ownership of free pages
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700867 */
Mel Gormand9c23402007-10-16 01:26:01 -0700868 if (unlikely(current_order >= (pageblock_order >> 1)) ||
Mel Gormandd5d2412009-09-05 11:17:11 -0700869 start_migratetype == MIGRATE_RECLAIMABLE ||
870 page_group_by_mobility_disabled) {
Mel Gorman46dafbc2007-10-16 01:25:55 -0700871 unsigned long pages;
872 pages = move_freepages_block(zone, page,
873 start_migratetype);
874
875 /* Claim the whole block if over half of it is free */
Mel Gormandd5d2412009-09-05 11:17:11 -0700876 if (pages >= (1 << (pageblock_order-1)) ||
877 page_group_by_mobility_disabled)
Mel Gorman46dafbc2007-10-16 01:25:55 -0700878 set_pageblock_migratetype(page,
879 start_migratetype);
880
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700881 migratetype = start_migratetype;
Mel Gormanc361be52007-10-16 01:25:51 -0700882 }
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700883
884 /* Remove the page from the freelists */
885 list_del(&page->lru);
886 rmv_page_order(page);
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700887
Mel Gorman2f66a682009-09-21 17:02:31 -0700888 /* Take ownership for orders >= pageblock_order */
889 if (current_order >= pageblock_order)
890 change_pageblock_range(page, current_order,
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700891 start_migratetype);
892
893 expand(zone, page, order, current_order, area, migratetype);
Mel Gormane0fff1b2009-09-21 17:02:42 -0700894
895 trace_mm_page_alloc_extfrag(page, order, current_order,
896 start_migratetype, migratetype);
897
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700898 return page;
899 }
900 }
901
Mel Gorman728ec982009-06-16 15:32:04 -0700902 return NULL;
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700903}
904
Mel Gorman56fd56b2007-10-16 01:25:58 -0700905/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700906 * Do the hard work of removing an element from the buddy allocator.
907 * Call me with the zone->lock already held.
908 */
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700909static struct page *__rmqueue(struct zone *zone, unsigned int order,
910 int migratetype)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700911{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700912 struct page *page;
913
Mel Gorman728ec982009-06-16 15:32:04 -0700914retry_reserve:
Mel Gorman56fd56b2007-10-16 01:25:58 -0700915 page = __rmqueue_smallest(zone, order, migratetype);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700916
Mel Gorman728ec982009-06-16 15:32:04 -0700917 if (unlikely(!page) && migratetype != MIGRATE_RESERVE) {
Mel Gorman56fd56b2007-10-16 01:25:58 -0700918 page = __rmqueue_fallback(zone, order, migratetype);
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700919
Mel Gorman728ec982009-06-16 15:32:04 -0700920 /*
921 * Use MIGRATE_RESERVE rather than fail an allocation. goto
922 * is used because __rmqueue_smallest is an inline function
923 * and we want just one call site
924 */
925 if (!page) {
926 migratetype = MIGRATE_RESERVE;
927 goto retry_reserve;
928 }
929 }
930
Mel Gorman0d3d0622009-09-21 17:02:44 -0700931 trace_mm_page_alloc_zone_locked(page, order, migratetype);
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700932 return page;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700933}
934
935/*
936 * Obtain a specified number of elements from the buddy allocator, all under
937 * a single hold of the lock, for efficiency. Add them to the supplied list.
938 * Returns the number of new pages which were placed at *list.
939 */
940static int rmqueue_bulk(struct zone *zone, unsigned int order,
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700941 unsigned long count, struct list_head *list,
Mel Gormane084b2d2009-07-29 15:02:04 -0700942 int migratetype, int cold)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700943{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700944 int i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700945
Nick Pigginc54ad302006-01-06 00:10:56 -0800946 spin_lock(&zone->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700947 for (i = 0; i < count; ++i) {
Mel Gormanb2a0ac82007-10-16 01:25:48 -0700948 struct page *page = __rmqueue(zone, order, migratetype);
Nick Piggin085cc7d2006-01-06 00:11:01 -0800949 if (unlikely(page == NULL))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700950 break;
Mel Gorman81eabcb2007-12-17 16:20:05 -0800951
952 /*
953 * Split buddy pages returned by expand() are received here
954 * in physical page order. The page is added to the callers and
955 * list and the list head then moves forward. From the callers
956 * perspective, the linked list is ordered by page number in
957 * some conditions. This is useful for IO devices that can
958 * merge IO requests if the physical pages are ordered
959 * properly.
960 */
Mel Gormane084b2d2009-07-29 15:02:04 -0700961 if (likely(cold == 0))
962 list_add(&page->lru, list);
963 else
964 list_add_tail(&page->lru, list);
Mel Gorman535131e2007-10-16 01:25:49 -0700965 set_page_private(page, migratetype);
Mel Gorman81eabcb2007-12-17 16:20:05 -0800966 list = &page->lru;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700967 }
Mel Gormanf2260e62009-06-16 15:32:13 -0700968 __mod_zone_page_state(zone, NR_FREE_PAGES, -(i << order));
Nick Pigginc54ad302006-01-06 00:10:56 -0800969 spin_unlock(&zone->lock);
Nick Piggin085cc7d2006-01-06 00:11:01 -0800970 return i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700971}
972
Christoph Lameter4ae7c032005-06-21 17:14:57 -0700973#ifdef CONFIG_NUMA
Christoph Lameter8fce4d82006-03-09 17:33:54 -0800974/*
Christoph Lameter4037d452007-05-09 02:35:14 -0700975 * Called from the vmstat counter updater to drain pagesets of this
976 * currently executing processor on remote nodes after they have
977 * expired.
978 *
Christoph Lameter879336c2006-03-22 00:09:08 -0800979 * Note that this function must be called with the thread pinned to
980 * a single processor.
Christoph Lameter8fce4d82006-03-09 17:33:54 -0800981 */
Christoph Lameter4037d452007-05-09 02:35:14 -0700982void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp)
Christoph Lameter4ae7c032005-06-21 17:14:57 -0700983{
Christoph Lameter4ae7c032005-06-21 17:14:57 -0700984 unsigned long flags;
Christoph Lameter4037d452007-05-09 02:35:14 -0700985 int to_drain;
Christoph Lameter4ae7c032005-06-21 17:14:57 -0700986
Christoph Lameter4037d452007-05-09 02:35:14 -0700987 local_irq_save(flags);
988 if (pcp->count >= pcp->batch)
989 to_drain = pcp->batch;
990 else
991 to_drain = pcp->count;
Mel Gorman5f8dcc22009-09-21 17:03:19 -0700992 free_pcppages_bulk(zone, to_drain, pcp);
Christoph Lameter4037d452007-05-09 02:35:14 -0700993 pcp->count -= to_drain;
994 local_irq_restore(flags);
Christoph Lameter4ae7c032005-06-21 17:14:57 -0700995}
996#endif
997
Christoph Lameter9f8f2172008-02-04 22:29:11 -0800998/*
999 * Drain pages of the indicated processor.
1000 *
1001 * The processor must either be the current processor and the
1002 * thread pinned to the current processor or a processor that
1003 * is not online.
1004 */
1005static void drain_pages(unsigned int cpu)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001006{
Nick Pigginc54ad302006-01-06 00:10:56 -08001007 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001008 struct zone *zone;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001009
KOSAKI Motohiroee99c712009-03-31 15:19:31 -07001010 for_each_populated_zone(zone) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001011 struct per_cpu_pageset *pset;
Christoph Lameter3dfa5722008-02-04 22:29:19 -08001012 struct per_cpu_pages *pcp;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001013
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07001014 pset = zone_pcp(zone, cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001015
Christoph Lameter3dfa5722008-02-04 22:29:19 -08001016 pcp = &pset->pcp;
1017 local_irq_save(flags);
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001018 free_pcppages_bulk(zone, pcp->count, pcp);
Christoph Lameter3dfa5722008-02-04 22:29:19 -08001019 pcp->count = 0;
1020 local_irq_restore(flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001021 }
1022}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001023
Christoph Lameter9f8f2172008-02-04 22:29:11 -08001024/*
1025 * Spill all of this CPU's per-cpu pages back into the buddy allocator.
1026 */
1027void drain_local_pages(void *arg)
1028{
1029 drain_pages(smp_processor_id());
1030}
1031
1032/*
1033 * Spill all the per-cpu pages from all CPUs back into the buddy allocator
1034 */
1035void drain_all_pages(void)
1036{
Jens Axboe15c8b6c2008-05-09 09:39:44 +02001037 on_each_cpu(drain_local_pages, NULL, 1);
Christoph Lameter9f8f2172008-02-04 22:29:11 -08001038}
1039
Rafael J. Wysocki296699d2007-07-29 23:27:18 +02001040#ifdef CONFIG_HIBERNATION
Linus Torvalds1da177e2005-04-16 15:20:36 -07001041
1042void mark_free_pages(struct zone *zone)
1043{
Rafael J. Wysockif623f0d2006-09-25 23:32:49 -07001044 unsigned long pfn, max_zone_pfn;
1045 unsigned long flags;
Mel Gormanb2a0ac82007-10-16 01:25:48 -07001046 int order, t;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001047 struct list_head *curr;
1048
1049 if (!zone->spanned_pages)
1050 return;
1051
1052 spin_lock_irqsave(&zone->lock, flags);
Rafael J. Wysockif623f0d2006-09-25 23:32:49 -07001053
1054 max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
1055 for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
1056 if (pfn_valid(pfn)) {
1057 struct page *page = pfn_to_page(pfn);
1058
Rafael J. Wysocki7be98232007-05-06 14:50:42 -07001059 if (!swsusp_page_is_forbidden(page))
1060 swsusp_unset_page_free(page);
Rafael J. Wysockif623f0d2006-09-25 23:32:49 -07001061 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001062
Mel Gormanb2a0ac82007-10-16 01:25:48 -07001063 for_each_migratetype_order(order, t) {
1064 list_for_each(curr, &zone->free_area[order].free_list[t]) {
Rafael J. Wysockif623f0d2006-09-25 23:32:49 -07001065 unsigned long i;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001066
Rafael J. Wysockif623f0d2006-09-25 23:32:49 -07001067 pfn = page_to_pfn(list_entry(curr, struct page, lru));
1068 for (i = 0; i < (1UL << order); i++)
Rafael J. Wysocki7be98232007-05-06 14:50:42 -07001069 swsusp_set_page_free(pfn_to_page(pfn + i));
Rafael J. Wysockif623f0d2006-09-25 23:32:49 -07001070 }
Mel Gormanb2a0ac82007-10-16 01:25:48 -07001071 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001072 spin_unlock_irqrestore(&zone->lock, flags);
1073}
Mel Gormane2c55dc2007-10-16 01:25:50 -07001074#endif /* CONFIG_PM */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001075
1076/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07001077 * Free a 0-order page
1078 */
Harvey Harrison920c7a52008-02-04 22:29:26 -08001079static void free_hot_cold_page(struct page *page, int cold)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001080{
1081 struct zone *zone = page_zone(page);
1082 struct per_cpu_pages *pcp;
1083 unsigned long flags;
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001084 int migratetype;
Johannes Weiner451ea252009-09-21 17:01:48 -07001085 int wasMlocked = __TestClearPageMlocked(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001086
Vegard Nossumb1eeab62008-11-25 16:55:53 +01001087 kmemcheck_free_shadow(page, 0);
1088
Linus Torvalds1da177e2005-04-16 15:20:36 -07001089 if (PageAnon(page))
1090 page->mapping = NULL;
Nick Piggin224abf92006-01-06 00:11:11 -08001091 if (free_pages_check(page))
Hugh Dickins689bceb2005-11-21 21:32:20 -08001092 return;
1093
Thomas Gleixner3ac7fe52008-04-30 00:55:01 -07001094 if (!PageHighMem(page)) {
Nick Piggin9858db52006-10-11 01:21:30 -07001095 debug_check_no_locks_freed(page_address(page), PAGE_SIZE);
Thomas Gleixner3ac7fe52008-04-30 00:55:01 -07001096 debug_check_no_obj_freed(page_address(page), PAGE_SIZE);
1097 }
Nick Piggindafb1362006-10-11 01:21:30 -07001098 arch_free_page(page, 0);
Hugh Dickins689bceb2005-11-21 21:32:20 -08001099 kernel_map_pages(page, 1, 0);
1100
Christoph Lameter3dfa5722008-02-04 22:29:19 -08001101 pcp = &zone_pcp(zone, get_cpu())->pcp;
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001102 migratetype = get_pageblock_migratetype(page);
1103 set_page_private(page, migratetype);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001104 local_irq_save(flags);
Johannes Weinerc2773312009-06-19 19:30:56 +02001105 if (unlikely(wasMlocked))
Mel Gormanda456f12009-06-16 15:32:08 -07001106 free_page_mlock(page);
Christoph Lameterf8891e52006-06-30 01:55:45 -07001107 __count_vm_event(PGFREE);
Mel Gormanda456f12009-06-16 15:32:08 -07001108
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001109 /*
1110 * We only track unmovable, reclaimable and movable on pcp lists.
1111 * Free ISOLATE pages back to the allocator because they are being
1112 * offlined but treat RESERVE as movable pages so we can get those
1113 * areas back if necessary. Otherwise, we may have to free
1114 * excessively into the page allocator
1115 */
1116 if (migratetype >= MIGRATE_PCPTYPES) {
1117 if (unlikely(migratetype == MIGRATE_ISOLATE)) {
1118 free_one_page(zone, page, 0, migratetype);
1119 goto out;
1120 }
1121 migratetype = MIGRATE_MOVABLE;
1122 }
1123
Christoph Lameter3dfa5722008-02-04 22:29:19 -08001124 if (cold)
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001125 list_add_tail(&page->lru, &pcp->lists[migratetype]);
Christoph Lameter3dfa5722008-02-04 22:29:19 -08001126 else
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001127 list_add(&page->lru, &pcp->lists[migratetype]);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001128 pcp->count++;
Nick Piggin48db57f2006-01-08 01:00:42 -08001129 if (pcp->count >= pcp->high) {
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001130 free_pcppages_bulk(zone, pcp->batch, pcp);
Nick Piggin48db57f2006-01-08 01:00:42 -08001131 pcp->count -= pcp->batch;
1132 }
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001133
1134out:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001135 local_irq_restore(flags);
1136 put_cpu();
1137}
1138
Harvey Harrison920c7a52008-02-04 22:29:26 -08001139void free_hot_page(struct page *page)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001140{
Mel Gorman4b4f2782009-09-21 17:02:41 -07001141 trace_mm_page_free_direct(page, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001142 free_hot_cold_page(page, 0);
1143}
1144
Nick Piggin8dfcc9b2006-03-22 00:08:05 -08001145/*
1146 * split_page takes a non-compound higher-order page, and splits it into
1147 * n (1<<order) sub-pages: page[0..n]
1148 * Each sub-page must be freed individually.
1149 *
1150 * Note: this is probably too low level an operation for use in drivers.
1151 * Please consult with lkml before using this in your driver.
1152 */
1153void split_page(struct page *page, unsigned int order)
1154{
1155 int i;
1156
Nick Piggin725d7042006-09-25 23:30:55 -07001157 VM_BUG_ON(PageCompound(page));
1158 VM_BUG_ON(!page_count(page));
Vegard Nossumb1eeab62008-11-25 16:55:53 +01001159
1160#ifdef CONFIG_KMEMCHECK
1161 /*
1162 * Split shadow pages too, because free(page[0]) would
1163 * otherwise free the whole shadow.
1164 */
1165 if (kmemcheck_page_is_tracked(page))
1166 split_page(virt_to_page(page[0].shadow), order);
1167#endif
1168
Nick Piggin7835e982006-03-22 00:08:40 -08001169 for (i = 1; i < (1 << order); i++)
1170 set_page_refcounted(page + i);
Nick Piggin8dfcc9b2006-03-22 00:08:05 -08001171}
Nick Piggin8dfcc9b2006-03-22 00:08:05 -08001172
Linus Torvalds1da177e2005-04-16 15:20:36 -07001173/*
1174 * Really, prep_compound_page() should be called from __rmqueue_bulk(). But
1175 * we cheat by calling it from here, in the order > 0 path. Saves a branch
1176 * or two.
1177 */
Mel Gorman0a15c3e2009-06-16 15:32:05 -07001178static inline
1179struct page *buffered_rmqueue(struct zone *preferred_zone,
Mel Gorman3dd28262009-06-16 15:32:00 -07001180 struct zone *zone, int order, gfp_t gfp_flags,
1181 int migratetype)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001182{
1183 unsigned long flags;
Hugh Dickins689bceb2005-11-21 21:32:20 -08001184 struct page *page;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001185 int cold = !!(gfp_flags & __GFP_COLD);
Nick Piggina74609f2006-01-06 00:11:20 -08001186 int cpu;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001187
Hugh Dickins689bceb2005-11-21 21:32:20 -08001188again:
Nick Piggina74609f2006-01-06 00:11:20 -08001189 cpu = get_cpu();
Nick Piggin48db57f2006-01-08 01:00:42 -08001190 if (likely(order == 0)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001191 struct per_cpu_pages *pcp;
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001192 struct list_head *list;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001193
Christoph Lameter3dfa5722008-02-04 22:29:19 -08001194 pcp = &zone_pcp(zone, cpu)->pcp;
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001195 list = &pcp->lists[migratetype];
Linus Torvalds1da177e2005-04-16 15:20:36 -07001196 local_irq_save(flags);
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001197 if (list_empty(list)) {
Mel Gorman535131e2007-10-16 01:25:49 -07001198 pcp->count += rmqueue_bulk(zone, 0,
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001199 pcp->batch, list,
Mel Gormane084b2d2009-07-29 15:02:04 -07001200 migratetype, cold);
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001201 if (unlikely(list_empty(list)))
Shaohua Li6fb332f2009-09-21 17:01:17 -07001202 goto failed;
Mel Gorman535131e2007-10-16 01:25:49 -07001203 }
Mel Gormanb92a6ed2007-10-16 01:25:50 -07001204
Mel Gorman5f8dcc22009-09-21 17:03:19 -07001205 if (cold)
1206 page = list_entry(list->prev, struct page, lru);
1207 else
1208 page = list_entry(list->next, struct page, lru);
1209
Mel Gormanb92a6ed2007-10-16 01:25:50 -07001210 list_del(&page->lru);
1211 pcp->count--;
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001212 } else {
Andrew Mortondab48da2009-06-16 15:32:37 -07001213 if (unlikely(gfp_flags & __GFP_NOFAIL)) {
1214 /*
1215 * __GFP_NOFAIL is not to be used in new code.
1216 *
1217 * All __GFP_NOFAIL callers should be fixed so that they
1218 * properly detect and handle allocation failures.
1219 *
1220 * We most definitely don't want callers attempting to
Linus Torvalds4923abf2009-06-24 12:16:49 -07001221 * allocate greater than order-1 page units with
Andrew Mortondab48da2009-06-16 15:32:37 -07001222 * __GFP_NOFAIL.
1223 */
Linus Torvalds4923abf2009-06-24 12:16:49 -07001224 WARN_ON_ONCE(order > 1);
Andrew Mortondab48da2009-06-16 15:32:37 -07001225 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001226 spin_lock_irqsave(&zone->lock, flags);
Mel Gormanb2a0ac82007-10-16 01:25:48 -07001227 page = __rmqueue(zone, order, migratetype);
Mel Gormanf2260e62009-06-16 15:32:13 -07001228 __mod_zone_page_state(zone, NR_FREE_PAGES, -(1 << order));
Nick Piggina74609f2006-01-06 00:11:20 -08001229 spin_unlock(&zone->lock);
1230 if (!page)
1231 goto failed;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001232 }
1233
Christoph Lameterf8891e52006-06-30 01:55:45 -07001234 __count_zone_vm_events(PGALLOC, zone, 1 << order);
Mel Gorman18ea7e72008-04-28 02:12:14 -07001235 zone_statistics(preferred_zone, zone);
Nick Piggina74609f2006-01-06 00:11:20 -08001236 local_irq_restore(flags);
1237 put_cpu();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001238
Nick Piggin725d7042006-09-25 23:30:55 -07001239 VM_BUG_ON(bad_range(zone, page));
Nick Piggin17cf4402006-03-22 00:08:41 -08001240 if (prep_new_page(page, order, gfp_flags))
Nick Piggina74609f2006-01-06 00:11:20 -08001241 goto again;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001242 return page;
Nick Piggina74609f2006-01-06 00:11:20 -08001243
1244failed:
1245 local_irq_restore(flags);
1246 put_cpu();
1247 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001248}
1249
Mel Gorman41858962009-06-16 15:32:12 -07001250/* The ALLOC_WMARK bits are used as an index to zone->watermark */
1251#define ALLOC_WMARK_MIN WMARK_MIN
1252#define ALLOC_WMARK_LOW WMARK_LOW
1253#define ALLOC_WMARK_HIGH WMARK_HIGH
1254#define ALLOC_NO_WATERMARKS 0x04 /* don't check watermarks at all */
1255
1256/* Mask to get the watermark bits */
1257#define ALLOC_WMARK_MASK (ALLOC_NO_WATERMARKS-1)
1258
Nick Piggin31488902005-11-28 13:44:03 -08001259#define ALLOC_HARDER 0x10 /* try to alloc harder */
1260#define ALLOC_HIGH 0x20 /* __GFP_HIGH set */
1261#define ALLOC_CPUSET 0x40 /* check for correct cpuset */
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001262
Akinobu Mita933e3122006-12-08 02:39:45 -08001263#ifdef CONFIG_FAIL_PAGE_ALLOC
1264
1265static struct fail_page_alloc_attr {
1266 struct fault_attr attr;
1267
1268 u32 ignore_gfp_highmem;
1269 u32 ignore_gfp_wait;
Akinobu Mita54114992007-07-15 23:40:23 -07001270 u32 min_order;
Akinobu Mita933e3122006-12-08 02:39:45 -08001271
1272#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
1273
1274 struct dentry *ignore_gfp_highmem_file;
1275 struct dentry *ignore_gfp_wait_file;
Akinobu Mita54114992007-07-15 23:40:23 -07001276 struct dentry *min_order_file;
Akinobu Mita933e3122006-12-08 02:39:45 -08001277
1278#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
1279
1280} fail_page_alloc = {
1281 .attr = FAULT_ATTR_INITIALIZER,
Don Mullis6b1b60f2006-12-08 02:39:53 -08001282 .ignore_gfp_wait = 1,
1283 .ignore_gfp_highmem = 1,
Akinobu Mita54114992007-07-15 23:40:23 -07001284 .min_order = 1,
Akinobu Mita933e3122006-12-08 02:39:45 -08001285};
1286
1287static int __init setup_fail_page_alloc(char *str)
1288{
1289 return setup_fault_attr(&fail_page_alloc.attr, str);
1290}
1291__setup("fail_page_alloc=", setup_fail_page_alloc);
1292
1293static int should_fail_alloc_page(gfp_t gfp_mask, unsigned int order)
1294{
Akinobu Mita54114992007-07-15 23:40:23 -07001295 if (order < fail_page_alloc.min_order)
1296 return 0;
Akinobu Mita933e3122006-12-08 02:39:45 -08001297 if (gfp_mask & __GFP_NOFAIL)
1298 return 0;
1299 if (fail_page_alloc.ignore_gfp_highmem && (gfp_mask & __GFP_HIGHMEM))
1300 return 0;
1301 if (fail_page_alloc.ignore_gfp_wait && (gfp_mask & __GFP_WAIT))
1302 return 0;
1303
1304 return should_fail(&fail_page_alloc.attr, 1 << order);
1305}
1306
1307#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
1308
1309static int __init fail_page_alloc_debugfs(void)
1310{
1311 mode_t mode = S_IFREG | S_IRUSR | S_IWUSR;
1312 struct dentry *dir;
1313 int err;
1314
1315 err = init_fault_attr_dentries(&fail_page_alloc.attr,
1316 "fail_page_alloc");
1317 if (err)
1318 return err;
1319 dir = fail_page_alloc.attr.dentries.dir;
1320
1321 fail_page_alloc.ignore_gfp_wait_file =
1322 debugfs_create_bool("ignore-gfp-wait", mode, dir,
1323 &fail_page_alloc.ignore_gfp_wait);
1324
1325 fail_page_alloc.ignore_gfp_highmem_file =
1326 debugfs_create_bool("ignore-gfp-highmem", mode, dir,
1327 &fail_page_alloc.ignore_gfp_highmem);
Akinobu Mita54114992007-07-15 23:40:23 -07001328 fail_page_alloc.min_order_file =
1329 debugfs_create_u32("min-order", mode, dir,
1330 &fail_page_alloc.min_order);
Akinobu Mita933e3122006-12-08 02:39:45 -08001331
1332 if (!fail_page_alloc.ignore_gfp_wait_file ||
Akinobu Mita54114992007-07-15 23:40:23 -07001333 !fail_page_alloc.ignore_gfp_highmem_file ||
1334 !fail_page_alloc.min_order_file) {
Akinobu Mita933e3122006-12-08 02:39:45 -08001335 err = -ENOMEM;
1336 debugfs_remove(fail_page_alloc.ignore_gfp_wait_file);
1337 debugfs_remove(fail_page_alloc.ignore_gfp_highmem_file);
Akinobu Mita54114992007-07-15 23:40:23 -07001338 debugfs_remove(fail_page_alloc.min_order_file);
Akinobu Mita933e3122006-12-08 02:39:45 -08001339 cleanup_fault_attr_dentries(&fail_page_alloc.attr);
1340 }
1341
1342 return err;
1343}
1344
1345late_initcall(fail_page_alloc_debugfs);
1346
1347#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
1348
1349#else /* CONFIG_FAIL_PAGE_ALLOC */
1350
1351static inline int should_fail_alloc_page(gfp_t gfp_mask, unsigned int order)
1352{
1353 return 0;
1354}
1355
1356#endif /* CONFIG_FAIL_PAGE_ALLOC */
1357
Linus Torvalds1da177e2005-04-16 15:20:36 -07001358/*
1359 * Return 1 if free pages are above 'mark'. This takes into account the order
1360 * of the allocation.
1361 */
1362int zone_watermark_ok(struct zone *z, int order, unsigned long mark,
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001363 int classzone_idx, int alloc_flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001364{
1365 /* free_pages my go negative - that's OK */
Christoph Lameterd23ad422007-02-10 01:43:02 -08001366 long min = mark;
1367 long free_pages = zone_page_state(z, NR_FREE_PAGES) - (1 << order) + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001368 int o;
1369
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001370 if (alloc_flags & ALLOC_HIGH)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001371 min -= min / 2;
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001372 if (alloc_flags & ALLOC_HARDER)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001373 min -= min / 4;
1374
1375 if (free_pages <= min + z->lowmem_reserve[classzone_idx])
1376 return 0;
1377 for (o = 0; o < order; o++) {
1378 /* At the next order, this order's pages become unavailable */
1379 free_pages -= z->free_area[o].nr_free << o;
1380
1381 /* Require fewer higher order pages to be free */
1382 min >>= 1;
1383
1384 if (free_pages <= min)
1385 return 0;
1386 }
1387 return 1;
1388}
1389
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001390#ifdef CONFIG_NUMA
1391/*
1392 * zlc_setup - Setup for "zonelist cache". Uses cached zone data to
1393 * skip over zones that are not allowed by the cpuset, or that have
1394 * been recently (in last second) found to be nearly full. See further
1395 * comments in mmzone.h. Reduces cache footprint of zonelist scans
Simon Arlott183ff222007-10-20 01:27:18 +02001396 * that have to skip over a lot of full or unallowed zones.
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001397 *
1398 * If the zonelist cache is present in the passed in zonelist, then
1399 * returns a pointer to the allowed node mask (either the current
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07001400 * tasks mems_allowed, or node_states[N_HIGH_MEMORY].)
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001401 *
1402 * If the zonelist cache is not available for this zonelist, does
1403 * nothing and returns NULL.
1404 *
1405 * If the fullzones BITMAP in the zonelist cache is stale (more than
1406 * a second since last zap'd) then we zap it out (clear its bits.)
1407 *
1408 * We hold off even calling zlc_setup, until after we've checked the
1409 * first zone in the zonelist, on the theory that most allocations will
1410 * be satisfied from that first zone, so best to examine that zone as
1411 * quickly as we can.
1412 */
1413static nodemask_t *zlc_setup(struct zonelist *zonelist, int alloc_flags)
1414{
1415 struct zonelist_cache *zlc; /* cached zonelist speedup info */
1416 nodemask_t *allowednodes; /* zonelist_cache approximation */
1417
1418 zlc = zonelist->zlcache_ptr;
1419 if (!zlc)
1420 return NULL;
1421
S.Caglar Onurf05111f2008-04-28 02:12:38 -07001422 if (time_after(jiffies, zlc->last_full_zap + HZ)) {
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001423 bitmap_zero(zlc->fullzones, MAX_ZONES_PER_ZONELIST);
1424 zlc->last_full_zap = jiffies;
1425 }
1426
1427 allowednodes = !in_interrupt() && (alloc_flags & ALLOC_CPUSET) ?
1428 &cpuset_current_mems_allowed :
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07001429 &node_states[N_HIGH_MEMORY];
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001430 return allowednodes;
1431}
1432
1433/*
1434 * Given 'z' scanning a zonelist, run a couple of quick checks to see
1435 * if it is worth looking at further for free memory:
1436 * 1) Check that the zone isn't thought to be full (doesn't have its
1437 * bit set in the zonelist_cache fullzones BITMAP).
1438 * 2) Check that the zones node (obtained from the zonelist_cache
1439 * z_to_n[] mapping) is allowed in the passed in allowednodes mask.
1440 * Return true (non-zero) if zone is worth looking at further, or
1441 * else return false (zero) if it is not.
1442 *
1443 * This check -ignores- the distinction between various watermarks,
1444 * such as GFP_HIGH, GFP_ATOMIC, PF_MEMALLOC, ... If a zone is
1445 * found to be full for any variation of these watermarks, it will
1446 * be considered full for up to one second by all requests, unless
1447 * we are so low on memory on all allowed nodes that we are forced
1448 * into the second scan of the zonelist.
1449 *
1450 * In the second scan we ignore this zonelist cache and exactly
1451 * apply the watermarks to all zones, even it is slower to do so.
1452 * We are low on memory in the second scan, and should leave no stone
1453 * unturned looking for a free page.
1454 */
Mel Gormandd1a2392008-04-28 02:12:17 -07001455static int zlc_zone_worth_trying(struct zonelist *zonelist, struct zoneref *z,
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001456 nodemask_t *allowednodes)
1457{
1458 struct zonelist_cache *zlc; /* cached zonelist speedup info */
1459 int i; /* index of *z in zonelist zones */
1460 int n; /* node that zone *z is on */
1461
1462 zlc = zonelist->zlcache_ptr;
1463 if (!zlc)
1464 return 1;
1465
Mel Gormandd1a2392008-04-28 02:12:17 -07001466 i = z - zonelist->_zonerefs;
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001467 n = zlc->z_to_n[i];
1468
1469 /* This zone is worth trying if it is allowed but not full */
1470 return node_isset(n, *allowednodes) && !test_bit(i, zlc->fullzones);
1471}
1472
1473/*
1474 * Given 'z' scanning a zonelist, set the corresponding bit in
1475 * zlc->fullzones, so that subsequent attempts to allocate a page
1476 * from that zone don't waste time re-examining it.
1477 */
Mel Gormandd1a2392008-04-28 02:12:17 -07001478static void zlc_mark_zone_full(struct zonelist *zonelist, struct zoneref *z)
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001479{
1480 struct zonelist_cache *zlc; /* cached zonelist speedup info */
1481 int i; /* index of *z in zonelist zones */
1482
1483 zlc = zonelist->zlcache_ptr;
1484 if (!zlc)
1485 return;
1486
Mel Gormandd1a2392008-04-28 02:12:17 -07001487 i = z - zonelist->_zonerefs;
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001488
1489 set_bit(i, zlc->fullzones);
1490}
1491
1492#else /* CONFIG_NUMA */
1493
1494static nodemask_t *zlc_setup(struct zonelist *zonelist, int alloc_flags)
1495{
1496 return NULL;
1497}
1498
Mel Gormandd1a2392008-04-28 02:12:17 -07001499static int zlc_zone_worth_trying(struct zonelist *zonelist, struct zoneref *z,
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001500 nodemask_t *allowednodes)
1501{
1502 return 1;
1503}
1504
Mel Gormandd1a2392008-04-28 02:12:17 -07001505static void zlc_mark_zone_full(struct zonelist *zonelist, struct zoneref *z)
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001506{
1507}
1508#endif /* CONFIG_NUMA */
1509
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001510/*
Paul Jackson0798e512006-12-06 20:31:38 -08001511 * get_page_from_freelist goes through the zonelist trying to allocate
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001512 * a page.
1513 */
1514static struct page *
Mel Gorman19770b32008-04-28 02:12:18 -07001515get_page_from_freelist(gfp_t gfp_mask, nodemask_t *nodemask, unsigned int order,
Mel Gorman5117f452009-06-16 15:31:59 -07001516 struct zonelist *zonelist, int high_zoneidx, int alloc_flags,
Mel Gorman3dd28262009-06-16 15:32:00 -07001517 struct zone *preferred_zone, int migratetype)
Martin Hicks753ee722005-06-21 17:14:41 -07001518{
Mel Gormandd1a2392008-04-28 02:12:17 -07001519 struct zoneref *z;
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001520 struct page *page = NULL;
Mel Gorman54a6eb52008-04-28 02:12:16 -07001521 int classzone_idx;
Mel Gorman5117f452009-06-16 15:31:59 -07001522 struct zone *zone;
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001523 nodemask_t *allowednodes = NULL;/* zonelist_cache approximation */
1524 int zlc_active = 0; /* set if using zonelist_cache */
1525 int did_zlc_setup = 0; /* just call zlc_setup() one time */
Mel Gorman54a6eb52008-04-28 02:12:16 -07001526
Mel Gorman19770b32008-04-28 02:12:18 -07001527 classzone_idx = zone_idx(preferred_zone);
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001528zonelist_scan:
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001529 /*
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001530 * Scan zonelist, looking for a zone with enough free.
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001531 * See also cpuset_zone_allowed() comment in kernel/cpuset.c.
1532 */
Mel Gorman19770b32008-04-28 02:12:18 -07001533 for_each_zone_zonelist_nodemask(zone, z, zonelist,
1534 high_zoneidx, nodemask) {
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001535 if (NUMA_BUILD && zlc_active &&
1536 !zlc_zone_worth_trying(zonelist, z, allowednodes))
1537 continue;
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001538 if ((alloc_flags & ALLOC_CPUSET) &&
Paul Jackson02a0e532006-12-13 00:34:25 -08001539 !cpuset_zone_allowed_softwall(zone, gfp_mask))
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001540 goto try_next_zone;
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001541
Mel Gorman41858962009-06-16 15:32:12 -07001542 BUILD_BUG_ON(ALLOC_NO_WATERMARKS < NR_WMARK);
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001543 if (!(alloc_flags & ALLOC_NO_WATERMARKS)) {
Nick Piggin31488902005-11-28 13:44:03 -08001544 unsigned long mark;
Mel Gormanfa5e0842009-06-16 15:33:22 -07001545 int ret;
1546
Mel Gorman41858962009-06-16 15:32:12 -07001547 mark = zone->watermark[alloc_flags & ALLOC_WMARK_MASK];
Mel Gormanfa5e0842009-06-16 15:33:22 -07001548 if (zone_watermark_ok(zone, order, mark,
1549 classzone_idx, alloc_flags))
1550 goto try_this_zone;
1551
1552 if (zone_reclaim_mode == 0)
1553 goto this_zone_full;
1554
1555 ret = zone_reclaim(zone, gfp_mask, order);
1556 switch (ret) {
1557 case ZONE_RECLAIM_NOSCAN:
1558 /* did not scan */
1559 goto try_next_zone;
1560 case ZONE_RECLAIM_FULL:
1561 /* scanned but unreclaimable */
1562 goto this_zone_full;
1563 default:
1564 /* did we reclaim enough */
1565 if (!zone_watermark_ok(zone, order, mark,
1566 classzone_idx, alloc_flags))
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001567 goto this_zone_full;
Paul Jackson0798e512006-12-06 20:31:38 -08001568 }
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001569 }
1570
Mel Gormanfa5e0842009-06-16 15:33:22 -07001571try_this_zone:
Mel Gorman3dd28262009-06-16 15:32:00 -07001572 page = buffered_rmqueue(preferred_zone, zone, order,
1573 gfp_mask, migratetype);
Paul Jackson0798e512006-12-06 20:31:38 -08001574 if (page)
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001575 break;
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001576this_zone_full:
1577 if (NUMA_BUILD)
1578 zlc_mark_zone_full(zonelist, z);
1579try_next_zone:
Christoph Lameter62bc62a2009-06-16 15:32:15 -07001580 if (NUMA_BUILD && !did_zlc_setup && nr_online_nodes > 1) {
Mel Gormand395b732009-06-16 15:32:09 -07001581 /*
1582 * we do zlc_setup after the first zone is tried but only
1583 * if there are multiple nodes make it worthwhile
1584 */
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001585 allowednodes = zlc_setup(zonelist, alloc_flags);
1586 zlc_active = 1;
1587 did_zlc_setup = 1;
1588 }
Mel Gorman54a6eb52008-04-28 02:12:16 -07001589 }
Paul Jackson9276b1bc2006-12-06 20:31:48 -08001590
1591 if (unlikely(NUMA_BUILD && page == NULL && zlc_active)) {
1592 /* Disable zlc cache for second zonelist scan */
1593 zlc_active = 0;
1594 goto zonelist_scan;
1595 }
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001596 return page;
Martin Hicks753ee722005-06-21 17:14:41 -07001597}
1598
Mel Gorman11e33f62009-06-16 15:31:57 -07001599static inline int
1600should_alloc_retry(gfp_t gfp_mask, unsigned int order,
1601 unsigned long pages_reclaimed)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001602{
Mel Gorman11e33f62009-06-16 15:31:57 -07001603 /* Do not loop if specifically requested */
1604 if (gfp_mask & __GFP_NORETRY)
1605 return 0;
1606
1607 /*
1608 * In this implementation, order <= PAGE_ALLOC_COSTLY_ORDER
1609 * means __GFP_NOFAIL, but that may not be true in other
1610 * implementations.
1611 */
1612 if (order <= PAGE_ALLOC_COSTLY_ORDER)
1613 return 1;
1614
1615 /*
1616 * For order > PAGE_ALLOC_COSTLY_ORDER, if __GFP_REPEAT is
1617 * specified, then we retry until we no longer reclaim any pages
1618 * (above), or we've reclaimed an order of pages at least as
1619 * large as the allocation's order. In both cases, if the
1620 * allocation still fails, we stop retrying.
1621 */
1622 if (gfp_mask & __GFP_REPEAT && pages_reclaimed < (1 << order))
1623 return 1;
1624
1625 /*
1626 * Don't let big-order allocations loop unless the caller
1627 * explicitly requests that.
1628 */
1629 if (gfp_mask & __GFP_NOFAIL)
1630 return 1;
1631
1632 return 0;
1633}
1634
1635static inline struct page *
1636__alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order,
1637 struct zonelist *zonelist, enum zone_type high_zoneidx,
Mel Gorman3dd28262009-06-16 15:32:00 -07001638 nodemask_t *nodemask, struct zone *preferred_zone,
1639 int migratetype)
Mel Gorman11e33f62009-06-16 15:31:57 -07001640{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001641 struct page *page;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001642
Mel Gorman11e33f62009-06-16 15:31:57 -07001643 /* Acquire the OOM killer lock for the zones in zonelist */
1644 if (!try_set_zone_oom(zonelist, gfp_mask)) {
1645 schedule_timeout_uninterruptible(1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001646 return NULL;
1647 }
Jens Axboe6b1de912005-11-17 21:35:02 +01001648
Mel Gorman11e33f62009-06-16 15:31:57 -07001649 /*
1650 * Go through the zonelist yet one more time, keep very high watermark
1651 * here, this is only to catch a parallel oom killing, we must fail if
1652 * we're still under heavy pressure.
1653 */
1654 page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask,
1655 order, zonelist, high_zoneidx,
Mel Gorman5117f452009-06-16 15:31:59 -07001656 ALLOC_WMARK_HIGH|ALLOC_CPUSET,
Mel Gorman3dd28262009-06-16 15:32:00 -07001657 preferred_zone, migratetype);
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001658 if (page)
Mel Gorman11e33f62009-06-16 15:31:57 -07001659 goto out;
1660
1661 /* The OOM killer will not help higher order allocs */
David Rientjes82553a92009-06-16 15:32:58 -07001662 if (order > PAGE_ALLOC_COSTLY_ORDER && !(gfp_mask & __GFP_NOFAIL))
Mel Gorman11e33f62009-06-16 15:31:57 -07001663 goto out;
1664
1665 /* Exhausted what can be done so it's blamo time */
1666 out_of_memory(zonelist, gfp_mask, order);
1667
1668out:
1669 clear_zonelist_oom(zonelist, gfp_mask);
1670 return page;
1671}
1672
1673/* The really slow allocator path where we enter direct reclaim */
1674static inline struct page *
1675__alloc_pages_direct_reclaim(gfp_t gfp_mask, unsigned int order,
1676 struct zonelist *zonelist, enum zone_type high_zoneidx,
Mel Gorman5117f452009-06-16 15:31:59 -07001677 nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone,
Mel Gorman3dd28262009-06-16 15:32:00 -07001678 int migratetype, unsigned long *did_some_progress)
Mel Gorman11e33f62009-06-16 15:31:57 -07001679{
1680 struct page *page = NULL;
1681 struct reclaim_state reclaim_state;
1682 struct task_struct *p = current;
1683
1684 cond_resched();
1685
1686 /* We now go into synchronous reclaim */
1687 cpuset_memory_pressure_bump();
Mel Gorman11e33f62009-06-16 15:31:57 -07001688 p->flags |= PF_MEMALLOC;
1689 lockdep_set_current_reclaim_state(gfp_mask);
1690 reclaim_state.reclaimed_slab = 0;
1691 p->reclaim_state = &reclaim_state;
1692
1693 *did_some_progress = try_to_free_pages(zonelist, order, gfp_mask, nodemask);
1694
1695 p->reclaim_state = NULL;
1696 lockdep_clear_current_reclaim_state();
1697 p->flags &= ~PF_MEMALLOC;
1698
1699 cond_resched();
1700
1701 if (order != 0)
1702 drain_all_pages();
1703
1704 if (likely(*did_some_progress))
1705 page = get_page_from_freelist(gfp_mask, nodemask, order,
Mel Gorman5117f452009-06-16 15:31:59 -07001706 zonelist, high_zoneidx,
Mel Gorman3dd28262009-06-16 15:32:00 -07001707 alloc_flags, preferred_zone,
1708 migratetype);
Mel Gorman11e33f62009-06-16 15:31:57 -07001709 return page;
1710}
1711
Mel Gorman11e33f62009-06-16 15:31:57 -07001712/*
1713 * This is called in the allocator slow-path if the allocation request is of
1714 * sufficient urgency to ignore watermarks and take other desperate measures
1715 */
1716static inline struct page *
1717__alloc_pages_high_priority(gfp_t gfp_mask, unsigned int order,
1718 struct zonelist *zonelist, enum zone_type high_zoneidx,
Mel Gorman3dd28262009-06-16 15:32:00 -07001719 nodemask_t *nodemask, struct zone *preferred_zone,
1720 int migratetype)
Mel Gorman11e33f62009-06-16 15:31:57 -07001721{
1722 struct page *page;
1723
1724 do {
1725 page = get_page_from_freelist(gfp_mask, nodemask, order,
Mel Gorman5117f452009-06-16 15:31:59 -07001726 zonelist, high_zoneidx, ALLOC_NO_WATERMARKS,
Mel Gorman3dd28262009-06-16 15:32:00 -07001727 preferred_zone, migratetype);
Mel Gorman11e33f62009-06-16 15:31:57 -07001728
1729 if (!page && gfp_mask & __GFP_NOFAIL)
Jens Axboe8aa7e842009-07-09 14:52:32 +02001730 congestion_wait(BLK_RW_ASYNC, HZ/50);
Mel Gorman11e33f62009-06-16 15:31:57 -07001731 } while (!page && (gfp_mask & __GFP_NOFAIL));
1732
1733 return page;
1734}
1735
1736static inline
1737void wake_all_kswapd(unsigned int order, struct zonelist *zonelist,
1738 enum zone_type high_zoneidx)
1739{
1740 struct zoneref *z;
1741 struct zone *zone;
1742
1743 for_each_zone_zonelist(zone, z, zonelist, high_zoneidx)
1744 wakeup_kswapd(zone, order);
1745}
1746
Peter Zijlstra341ce062009-06-16 15:32:02 -07001747static inline int
1748gfp_to_alloc_flags(gfp_t gfp_mask)
1749{
1750 struct task_struct *p = current;
1751 int alloc_flags = ALLOC_WMARK_MIN | ALLOC_CPUSET;
1752 const gfp_t wait = gfp_mask & __GFP_WAIT;
1753
Mel Gormana56f57f2009-06-16 15:32:02 -07001754 /* __GFP_HIGH is assumed to be the same as ALLOC_HIGH to save a branch. */
1755 BUILD_BUG_ON(__GFP_HIGH != ALLOC_HIGH);
1756
Peter Zijlstra341ce062009-06-16 15:32:02 -07001757 /*
1758 * The caller may dip into page reserves a bit more if the caller
1759 * cannot run direct reclaim, or if the caller has realtime scheduling
1760 * policy or is asking for __GFP_HIGH memory. GFP_ATOMIC requests will
1761 * set both ALLOC_HARDER (!wait) and ALLOC_HIGH (__GFP_HIGH).
1762 */
Mel Gormana56f57f2009-06-16 15:32:02 -07001763 alloc_flags |= (gfp_mask & __GFP_HIGH);
Peter Zijlstra341ce062009-06-16 15:32:02 -07001764
1765 if (!wait) {
1766 alloc_flags |= ALLOC_HARDER;
1767 /*
1768 * Ignore cpuset if GFP_ATOMIC (!wait) rather than fail alloc.
1769 * See also cpuset_zone_allowed() comment in kernel/cpuset.c.
1770 */
1771 alloc_flags &= ~ALLOC_CPUSET;
Mel Gorman9d0ed602009-11-11 14:26:17 -08001772 } else if (unlikely(rt_task(p)) && !in_interrupt())
Peter Zijlstra341ce062009-06-16 15:32:02 -07001773 alloc_flags |= ALLOC_HARDER;
1774
1775 if (likely(!(gfp_mask & __GFP_NOMEMALLOC))) {
1776 if (!in_interrupt() &&
1777 ((p->flags & PF_MEMALLOC) ||
1778 unlikely(test_thread_flag(TIF_MEMDIE))))
1779 alloc_flags |= ALLOC_NO_WATERMARKS;
1780 }
1781
1782 return alloc_flags;
1783}
1784
Mel Gorman11e33f62009-06-16 15:31:57 -07001785static inline struct page *
1786__alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order,
1787 struct zonelist *zonelist, enum zone_type high_zoneidx,
Mel Gorman3dd28262009-06-16 15:32:00 -07001788 nodemask_t *nodemask, struct zone *preferred_zone,
1789 int migratetype)
Mel Gorman11e33f62009-06-16 15:31:57 -07001790{
1791 const gfp_t wait = gfp_mask & __GFP_WAIT;
1792 struct page *page = NULL;
1793 int alloc_flags;
1794 unsigned long pages_reclaimed = 0;
1795 unsigned long did_some_progress;
1796 struct task_struct *p = current;
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001797
Christoph Lameter952f3b52006-12-06 20:33:26 -08001798 /*
Mel Gorman72807a72009-06-16 15:32:18 -07001799 * In the slowpath, we sanity check order to avoid ever trying to
1800 * reclaim >= MAX_ORDER areas which will never succeed. Callers may
1801 * be using allocators in order of preference for an area that is
1802 * too large.
1803 */
Mel Gorman1fc28b72009-07-29 15:04:08 -07001804 if (order >= MAX_ORDER) {
1805 WARN_ON_ONCE(!(gfp_mask & __GFP_NOWARN));
Mel Gorman72807a72009-06-16 15:32:18 -07001806 return NULL;
Mel Gorman1fc28b72009-07-29 15:04:08 -07001807 }
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001808
Christoph Lameter952f3b52006-12-06 20:33:26 -08001809 /*
1810 * GFP_THISNODE (meaning __GFP_THISNODE, __GFP_NORETRY and
1811 * __GFP_NOWARN set) should not cause reclaim since the subsystem
1812 * (f.e. slab) using GFP_THISNODE may choose to trigger reclaim
1813 * using a larger set of nodes after it has established that the
1814 * allowed per node queues are empty and that nodes are
1815 * over allocated.
1816 */
1817 if (NUMA_BUILD && (gfp_mask & GFP_THISNODE) == GFP_THISNODE)
1818 goto nopage;
1819
Mel Gormancc4a6852009-11-11 14:26:14 -08001820restart:
Mel Gorman11e33f62009-06-16 15:31:57 -07001821 wake_all_kswapd(order, zonelist, high_zoneidx);
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001822
Paul Jackson9bf22292005-09-06 15:18:12 -07001823 /*
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001824 * OK, we're below the kswapd watermark and have kicked background
1825 * reclaim. Now things get more complex, so set up alloc_flags according
1826 * to how we want to proceed.
Paul Jackson9bf22292005-09-06 15:18:12 -07001827 */
Peter Zijlstra341ce062009-06-16 15:32:02 -07001828 alloc_flags = gfp_to_alloc_flags(gfp_mask);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001829
Peter Zijlstra341ce062009-06-16 15:32:02 -07001830 /* This is the last chance, in general, before the goto nopage. */
Mel Gorman19770b32008-04-28 02:12:18 -07001831 page = get_page_from_freelist(gfp_mask, nodemask, order, zonelist,
Peter Zijlstra341ce062009-06-16 15:32:02 -07001832 high_zoneidx, alloc_flags & ~ALLOC_NO_WATERMARKS,
1833 preferred_zone, migratetype);
Rohit Seth7fb1d9f2005-11-13 16:06:43 -08001834 if (page)
1835 goto got_pg;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001836
Kirill Korotaevb43a57b2006-12-06 20:32:27 -08001837rebalance:
Mel Gorman11e33f62009-06-16 15:31:57 -07001838 /* Allocate without watermarks if the context allows */
Peter Zijlstra341ce062009-06-16 15:32:02 -07001839 if (alloc_flags & ALLOC_NO_WATERMARKS) {
1840 page = __alloc_pages_high_priority(gfp_mask, order,
1841 zonelist, high_zoneidx, nodemask,
1842 preferred_zone, migratetype);
1843 if (page)
1844 goto got_pg;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001845 }
1846
1847 /* Atomic allocations - we can't balance anything */
1848 if (!wait)
1849 goto nopage;
1850
Peter Zijlstra341ce062009-06-16 15:32:02 -07001851 /* Avoid recursion of direct reclaim */
1852 if (p->flags & PF_MEMALLOC)
1853 goto nopage;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001854
David Rientjes6583bb62009-07-29 15:02:06 -07001855 /* Avoid allocations with no watermarks from looping endlessly */
1856 if (test_thread_flag(TIF_MEMDIE) && !(gfp_mask & __GFP_NOFAIL))
1857 goto nopage;
1858
Mel Gorman11e33f62009-06-16 15:31:57 -07001859 /* Try direct reclaim and then allocating */
1860 page = __alloc_pages_direct_reclaim(gfp_mask, order,
1861 zonelist, high_zoneidx,
1862 nodemask,
Mel Gorman5117f452009-06-16 15:31:59 -07001863 alloc_flags, preferred_zone,
Mel Gorman3dd28262009-06-16 15:32:00 -07001864 migratetype, &did_some_progress);
Mel Gorman11e33f62009-06-16 15:31:57 -07001865 if (page)
1866 goto got_pg;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001867
Linus Torvalds1da177e2005-04-16 15:20:36 -07001868 /*
Mel Gorman11e33f62009-06-16 15:31:57 -07001869 * If we failed to make any progress reclaiming, then we are
1870 * running out of options and have to consider going OOM
Linus Torvalds1da177e2005-04-16 15:20:36 -07001871 */
Mel Gorman11e33f62009-06-16 15:31:57 -07001872 if (!did_some_progress) {
1873 if ((gfp_mask & __GFP_FS) && !(gfp_mask & __GFP_NORETRY)) {
Rafael J. Wysocki7f33d492009-06-16 15:32:41 -07001874 if (oom_killer_disabled)
1875 goto nopage;
Mel Gorman11e33f62009-06-16 15:31:57 -07001876 page = __alloc_pages_may_oom(gfp_mask, order,
1877 zonelist, high_zoneidx,
Mel Gorman3dd28262009-06-16 15:32:00 -07001878 nodemask, preferred_zone,
1879 migratetype);
Mel Gorman11e33f62009-06-16 15:31:57 -07001880 if (page)
1881 goto got_pg;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001882
Mel Gorman11e33f62009-06-16 15:31:57 -07001883 /*
David Rientjes82553a92009-06-16 15:32:58 -07001884 * The OOM killer does not trigger for high-order
1885 * ~__GFP_NOFAIL allocations so if no progress is being
1886 * made, there are no other options and retrying is
1887 * unlikely to help.
Mel Gorman11e33f62009-06-16 15:31:57 -07001888 */
David Rientjes82553a92009-06-16 15:32:58 -07001889 if (order > PAGE_ALLOC_COSTLY_ORDER &&
1890 !(gfp_mask & __GFP_NOFAIL))
Mel Gorman11e33f62009-06-16 15:31:57 -07001891 goto nopage;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001892
Linus Torvalds1da177e2005-04-16 15:20:36 -07001893 goto restart;
1894 }
1895 }
1896
Mel Gorman11e33f62009-06-16 15:31:57 -07001897 /* Check if we should retry the allocation */
Nishanth Aravamudana41f24e2008-04-29 00:58:25 -07001898 pages_reclaimed += did_some_progress;
Mel Gorman11e33f62009-06-16 15:31:57 -07001899 if (should_alloc_retry(gfp_mask, order, pages_reclaimed)) {
1900 /* Wait for some write requests to complete then retry */
Jens Axboe8aa7e842009-07-09 14:52:32 +02001901 congestion_wait(BLK_RW_ASYNC, HZ/50);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001902 goto rebalance;
1903 }
1904
1905nopage:
1906 if (!(gfp_mask & __GFP_NOWARN) && printk_ratelimit()) {
1907 printk(KERN_WARNING "%s: page allocation failure."
1908 " order:%d, mode:0x%x\n",
1909 p->comm, order, gfp_mask);
1910 dump_stack();
Janet Morgan578c2fd2005-06-21 17:14:56 -07001911 show_mem();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001912 }
Vegard Nossumb1eeab62008-11-25 16:55:53 +01001913 return page;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001914got_pg:
Vegard Nossumb1eeab62008-11-25 16:55:53 +01001915 if (kmemcheck_enabled)
1916 kmemcheck_pagealloc_alloc(page, order, gfp_mask);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001917 return page;
Mel Gorman11e33f62009-06-16 15:31:57 -07001918
Linus Torvalds1da177e2005-04-16 15:20:36 -07001919}
Mel Gorman11e33f62009-06-16 15:31:57 -07001920
1921/*
1922 * This is the 'heart' of the zoned buddy allocator.
1923 */
1924struct page *
1925__alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
1926 struct zonelist *zonelist, nodemask_t *nodemask)
1927{
1928 enum zone_type high_zoneidx = gfp_zone(gfp_mask);
Mel Gorman5117f452009-06-16 15:31:59 -07001929 struct zone *preferred_zone;
Mel Gorman11e33f62009-06-16 15:31:57 -07001930 struct page *page;
Mel Gorman3dd28262009-06-16 15:32:00 -07001931 int migratetype = allocflags_to_migratetype(gfp_mask);
Mel Gorman11e33f62009-06-16 15:31:57 -07001932
Benjamin Herrenschmidtdcce2842009-06-18 13:24:12 +10001933 gfp_mask &= gfp_allowed_mask;
1934
Mel Gorman11e33f62009-06-16 15:31:57 -07001935 lockdep_trace_alloc(gfp_mask);
1936
1937 might_sleep_if(gfp_mask & __GFP_WAIT);
1938
1939 if (should_fail_alloc_page(gfp_mask, order))
1940 return NULL;
1941
1942 /*
1943 * Check the zones suitable for the gfp_mask contain at least one
1944 * valid zone. It's possible to have an empty zonelist as a result
1945 * of GFP_THISNODE and a memoryless node
1946 */
1947 if (unlikely(!zonelist->_zonerefs->zone))
1948 return NULL;
1949
Mel Gorman5117f452009-06-16 15:31:59 -07001950 /* The preferred zone is used for statistics later */
1951 first_zones_zonelist(zonelist, high_zoneidx, nodemask, &preferred_zone);
1952 if (!preferred_zone)
1953 return NULL;
1954
1955 /* First allocation attempt */
Mel Gorman11e33f62009-06-16 15:31:57 -07001956 page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask, order,
Mel Gorman5117f452009-06-16 15:31:59 -07001957 zonelist, high_zoneidx, ALLOC_WMARK_LOW|ALLOC_CPUSET,
Mel Gorman3dd28262009-06-16 15:32:00 -07001958 preferred_zone, migratetype);
Mel Gorman11e33f62009-06-16 15:31:57 -07001959 if (unlikely(!page))
1960 page = __alloc_pages_slowpath(gfp_mask, order,
Mel Gorman5117f452009-06-16 15:31:59 -07001961 zonelist, high_zoneidx, nodemask,
Mel Gorman3dd28262009-06-16 15:32:00 -07001962 preferred_zone, migratetype);
Mel Gorman11e33f62009-06-16 15:31:57 -07001963
Mel Gorman4b4f2782009-09-21 17:02:41 -07001964 trace_mm_page_alloc(page, order, gfp_mask, migratetype);
Mel Gorman11e33f62009-06-16 15:31:57 -07001965 return page;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001966}
Mel Gormand2391712009-06-16 15:31:52 -07001967EXPORT_SYMBOL(__alloc_pages_nodemask);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001968
1969/*
1970 * Common helper functions.
1971 */
Harvey Harrison920c7a52008-02-04 22:29:26 -08001972unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001973{
Akinobu Mita945a1112009-09-21 17:01:47 -07001974 struct page *page;
1975
1976 /*
1977 * __get_free_pages() returns a 32-bit address, which cannot represent
1978 * a highmem page
1979 */
1980 VM_BUG_ON((gfp_mask & __GFP_HIGHMEM) != 0);
1981
Linus Torvalds1da177e2005-04-16 15:20:36 -07001982 page = alloc_pages(gfp_mask, order);
1983 if (!page)
1984 return 0;
1985 return (unsigned long) page_address(page);
1986}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001987EXPORT_SYMBOL(__get_free_pages);
1988
Harvey Harrison920c7a52008-02-04 22:29:26 -08001989unsigned long get_zeroed_page(gfp_t gfp_mask)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001990{
Akinobu Mita945a1112009-09-21 17:01:47 -07001991 return __get_free_pages(gfp_mask | __GFP_ZERO, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001992}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001993EXPORT_SYMBOL(get_zeroed_page);
1994
1995void __pagevec_free(struct pagevec *pvec)
1996{
1997 int i = pagevec_count(pvec);
1998
Mel Gorman4b4f2782009-09-21 17:02:41 -07001999 while (--i >= 0) {
2000 trace_mm_pagevec_free(pvec->pages[i], pvec->cold);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002001 free_hot_cold_page(pvec->pages[i], pvec->cold);
Mel Gorman4b4f2782009-09-21 17:02:41 -07002002 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002003}
2004
Harvey Harrison920c7a52008-02-04 22:29:26 -08002005void __free_pages(struct page *page, unsigned int order)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002006{
Nick Pigginb5810032005-10-29 18:16:12 -07002007 if (put_page_testzero(page)) {
Mel Gorman4b4f2782009-09-21 17:02:41 -07002008 trace_mm_page_free_direct(page, order);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002009 if (order == 0)
2010 free_hot_page(page);
2011 else
2012 __free_pages_ok(page, order);
2013 }
2014}
2015
2016EXPORT_SYMBOL(__free_pages);
2017
Harvey Harrison920c7a52008-02-04 22:29:26 -08002018void free_pages(unsigned long addr, unsigned int order)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002019{
2020 if (addr != 0) {
Nick Piggin725d7042006-09-25 23:30:55 -07002021 VM_BUG_ON(!virt_addr_valid((void *)addr));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002022 __free_pages(virt_to_page((void *)addr), order);
2023 }
2024}
2025
2026EXPORT_SYMBOL(free_pages);
2027
Timur Tabi2be0ffe2008-07-23 21:28:11 -07002028/**
2029 * alloc_pages_exact - allocate an exact number physically-contiguous pages.
2030 * @size: the number of bytes to allocate
2031 * @gfp_mask: GFP flags for the allocation
2032 *
2033 * This function is similar to alloc_pages(), except that it allocates the
2034 * minimum number of pages to satisfy the request. alloc_pages() can only
2035 * allocate memory in power-of-two pages.
2036 *
2037 * This function is also limited by MAX_ORDER.
2038 *
2039 * Memory allocated by this function must be released by free_pages_exact().
2040 */
2041void *alloc_pages_exact(size_t size, gfp_t gfp_mask)
2042{
2043 unsigned int order = get_order(size);
2044 unsigned long addr;
2045
2046 addr = __get_free_pages(gfp_mask, order);
2047 if (addr) {
2048 unsigned long alloc_end = addr + (PAGE_SIZE << order);
2049 unsigned long used = addr + PAGE_ALIGN(size);
2050
Kevin Cernekee5bfd7562009-07-05 12:08:19 -07002051 split_page(virt_to_page((void *)addr), order);
Timur Tabi2be0ffe2008-07-23 21:28:11 -07002052 while (used < alloc_end) {
2053 free_page(used);
2054 used += PAGE_SIZE;
2055 }
2056 }
2057
2058 return (void *)addr;
2059}
2060EXPORT_SYMBOL(alloc_pages_exact);
2061
2062/**
2063 * free_pages_exact - release memory allocated via alloc_pages_exact()
2064 * @virt: the value returned by alloc_pages_exact.
2065 * @size: size of allocation, same value as passed to alloc_pages_exact().
2066 *
2067 * Release the memory allocated by a previous call to alloc_pages_exact.
2068 */
2069void free_pages_exact(void *virt, size_t size)
2070{
2071 unsigned long addr = (unsigned long)virt;
2072 unsigned long end = addr + PAGE_ALIGN(size);
2073
2074 while (addr < end) {
2075 free_page(addr);
2076 addr += PAGE_SIZE;
2077 }
2078}
2079EXPORT_SYMBOL(free_pages_exact);
2080
Linus Torvalds1da177e2005-04-16 15:20:36 -07002081static unsigned int nr_free_zone_pages(int offset)
2082{
Mel Gormandd1a2392008-04-28 02:12:17 -07002083 struct zoneref *z;
Mel Gorman54a6eb52008-04-28 02:12:16 -07002084 struct zone *zone;
2085
Martin J. Blighe310fd42005-07-29 22:59:18 -07002086 /* Just pick one node, since fallback list is circular */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002087 unsigned int sum = 0;
2088
Mel Gorman0e884602008-04-28 02:12:14 -07002089 struct zonelist *zonelist = node_zonelist(numa_node_id(), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002090
Mel Gorman54a6eb52008-04-28 02:12:16 -07002091 for_each_zone_zonelist(zone, z, zonelist, offset) {
Martin J. Blighe310fd42005-07-29 22:59:18 -07002092 unsigned long size = zone->present_pages;
Mel Gorman41858962009-06-16 15:32:12 -07002093 unsigned long high = high_wmark_pages(zone);
Martin J. Blighe310fd42005-07-29 22:59:18 -07002094 if (size > high)
2095 sum += size - high;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002096 }
2097
2098 return sum;
2099}
2100
2101/*
2102 * Amount of free RAM allocatable within ZONE_DMA and ZONE_NORMAL
2103 */
2104unsigned int nr_free_buffer_pages(void)
2105{
Al Viroaf4ca452005-10-21 02:55:38 -04002106 return nr_free_zone_pages(gfp_zone(GFP_USER));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002107}
Meelap Shahc2f1a552007-07-17 04:04:39 -07002108EXPORT_SYMBOL_GPL(nr_free_buffer_pages);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002109
2110/*
2111 * Amount of free RAM allocatable within all zones
2112 */
2113unsigned int nr_free_pagecache_pages(void)
2114{
Mel Gorman2a1e2742007-07-17 04:03:12 -07002115 return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002116}
Christoph Lameter08e0f6a2006-09-27 01:50:06 -07002117
2118static inline void show_node(struct zone *zone)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002119{
Christoph Lameter08e0f6a2006-09-27 01:50:06 -07002120 if (NUMA_BUILD)
Andy Whitcroft25ba77c2006-12-06 20:33:03 -08002121 printk("Node %d ", zone_to_nid(zone));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002122}
Linus Torvalds1da177e2005-04-16 15:20:36 -07002123
Linus Torvalds1da177e2005-04-16 15:20:36 -07002124void si_meminfo(struct sysinfo *val)
2125{
2126 val->totalram = totalram_pages;
2127 val->sharedram = 0;
Christoph Lameterd23ad422007-02-10 01:43:02 -08002128 val->freeram = global_page_state(NR_FREE_PAGES);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002129 val->bufferram = nr_blockdev_pages();
Linus Torvalds1da177e2005-04-16 15:20:36 -07002130 val->totalhigh = totalhigh_pages;
2131 val->freehigh = nr_free_highpages();
Linus Torvalds1da177e2005-04-16 15:20:36 -07002132 val->mem_unit = PAGE_SIZE;
2133}
2134
2135EXPORT_SYMBOL(si_meminfo);
2136
2137#ifdef CONFIG_NUMA
2138void si_meminfo_node(struct sysinfo *val, int nid)
2139{
2140 pg_data_t *pgdat = NODE_DATA(nid);
2141
2142 val->totalram = pgdat->node_present_pages;
Christoph Lameterd23ad422007-02-10 01:43:02 -08002143 val->freeram = node_page_state(nid, NR_FREE_PAGES);
Christoph Lameter98d2b0e2006-09-25 23:31:12 -07002144#ifdef CONFIG_HIGHMEM
Linus Torvalds1da177e2005-04-16 15:20:36 -07002145 val->totalhigh = pgdat->node_zones[ZONE_HIGHMEM].present_pages;
Christoph Lameterd23ad422007-02-10 01:43:02 -08002146 val->freehigh = zone_page_state(&pgdat->node_zones[ZONE_HIGHMEM],
2147 NR_FREE_PAGES);
Christoph Lameter98d2b0e2006-09-25 23:31:12 -07002148#else
2149 val->totalhigh = 0;
2150 val->freehigh = 0;
2151#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07002152 val->mem_unit = PAGE_SIZE;
2153}
2154#endif
2155
2156#define K(x) ((x) << (PAGE_SHIFT-10))
2157
2158/*
2159 * Show free area list (used inside shift_scroll-lock stuff)
2160 * We also calculate the percentage fragmentation. We do this by counting the
2161 * memory on each free list with the exception of the first item on the list.
2162 */
2163void show_free_areas(void)
2164{
Jes Sorensenc7241912006-09-27 01:50:05 -07002165 int cpu;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002166 struct zone *zone;
2167
KOSAKI Motohiroee99c712009-03-31 15:19:31 -07002168 for_each_populated_zone(zone) {
Jes Sorensenc7241912006-09-27 01:50:05 -07002169 show_node(zone);
2170 printk("%s per-cpu:\n", zone->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002171
Dave Jones6b482c62005-11-10 15:45:56 -05002172 for_each_online_cpu(cpu) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002173 struct per_cpu_pageset *pageset;
2174
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07002175 pageset = zone_pcp(zone, cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002176
Christoph Lameter3dfa5722008-02-04 22:29:19 -08002177 printk("CPU %4d: hi:%5d, btch:%4d usd:%4d\n",
2178 cpu, pageset->pcp.high,
2179 pageset->pcp.batch, pageset->pcp.count);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002180 }
2181 }
2182
KOSAKI Motohiroa7312862009-09-21 17:01:37 -07002183 printk("active_anon:%lu inactive_anon:%lu isolated_anon:%lu\n"
2184 " active_file:%lu inactive_file:%lu isolated_file:%lu\n"
Lee Schermerhorn7b854122008-10-18 20:26:40 -07002185 " unevictable:%lu"
Andrew Mortonb76146e2009-10-26 16:49:52 -07002186 " dirty:%lu writeback:%lu unstable:%lu\n"
KOSAKI Motohiro3701b032009-09-21 17:01:29 -07002187 " free:%lu slab_reclaimable:%lu slab_unreclaimable:%lu\n"
KOSAKI Motohiro4b021082009-09-21 17:01:33 -07002188 " mapped:%lu shmem:%lu pagetables:%lu bounce:%lu\n",
Rik van Riel4f98a2f2008-10-18 20:26:32 -07002189 global_page_state(NR_ACTIVE_ANON),
Rik van Riel4f98a2f2008-10-18 20:26:32 -07002190 global_page_state(NR_INACTIVE_ANON),
KOSAKI Motohiroa7312862009-09-21 17:01:37 -07002191 global_page_state(NR_ISOLATED_ANON),
2192 global_page_state(NR_ACTIVE_FILE),
Rik van Riel4f98a2f2008-10-18 20:26:32 -07002193 global_page_state(NR_INACTIVE_FILE),
KOSAKI Motohiroa7312862009-09-21 17:01:37 -07002194 global_page_state(NR_ISOLATED_FILE),
Lee Schermerhorn7b854122008-10-18 20:26:40 -07002195 global_page_state(NR_UNEVICTABLE),
Christoph Lameterb1e7a8f2006-06-30 01:55:39 -07002196 global_page_state(NR_FILE_DIRTY),
Christoph Lameterce866b32006-06-30 01:55:40 -07002197 global_page_state(NR_WRITEBACK),
Christoph Lameterfd39fc82006-06-30 01:55:40 -07002198 global_page_state(NR_UNSTABLE_NFS),
Christoph Lameterd23ad422007-02-10 01:43:02 -08002199 global_page_state(NR_FREE_PAGES),
KOSAKI Motohiro3701b032009-09-21 17:01:29 -07002200 global_page_state(NR_SLAB_RECLAIMABLE),
2201 global_page_state(NR_SLAB_UNRECLAIMABLE),
Christoph Lameter65ba55f2006-06-30 01:55:34 -07002202 global_page_state(NR_FILE_MAPPED),
KOSAKI Motohiro4b021082009-09-21 17:01:33 -07002203 global_page_state(NR_SHMEM),
Andrew Mortona25700a2007-02-08 14:20:40 -08002204 global_page_state(NR_PAGETABLE),
2205 global_page_state(NR_BOUNCE));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002206
KOSAKI Motohiroee99c712009-03-31 15:19:31 -07002207 for_each_populated_zone(zone) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002208 int i;
2209
2210 show_node(zone);
2211 printk("%s"
2212 " free:%lukB"
2213 " min:%lukB"
2214 " low:%lukB"
2215 " high:%lukB"
Rik van Riel4f98a2f2008-10-18 20:26:32 -07002216 " active_anon:%lukB"
2217 " inactive_anon:%lukB"
2218 " active_file:%lukB"
2219 " inactive_file:%lukB"
Lee Schermerhorn7b854122008-10-18 20:26:40 -07002220 " unevictable:%lukB"
KOSAKI Motohiroa7312862009-09-21 17:01:37 -07002221 " isolated(anon):%lukB"
2222 " isolated(file):%lukB"
Linus Torvalds1da177e2005-04-16 15:20:36 -07002223 " present:%lukB"
KOSAKI Motohiro4a0aa732009-09-21 17:01:30 -07002224 " mlocked:%lukB"
2225 " dirty:%lukB"
2226 " writeback:%lukB"
2227 " mapped:%lukB"
KOSAKI Motohiro4b021082009-09-21 17:01:33 -07002228 " shmem:%lukB"
KOSAKI Motohiro4a0aa732009-09-21 17:01:30 -07002229 " slab_reclaimable:%lukB"
2230 " slab_unreclaimable:%lukB"
KOSAKI Motohiroc6a7f572009-09-21 17:01:32 -07002231 " kernel_stack:%lukB"
KOSAKI Motohiro4a0aa732009-09-21 17:01:30 -07002232 " pagetables:%lukB"
2233 " unstable:%lukB"
2234 " bounce:%lukB"
2235 " writeback_tmp:%lukB"
Linus Torvalds1da177e2005-04-16 15:20:36 -07002236 " pages_scanned:%lu"
2237 " all_unreclaimable? %s"
2238 "\n",
2239 zone->name,
Christoph Lameterd23ad422007-02-10 01:43:02 -08002240 K(zone_page_state(zone, NR_FREE_PAGES)),
Mel Gorman41858962009-06-16 15:32:12 -07002241 K(min_wmark_pages(zone)),
2242 K(low_wmark_pages(zone)),
2243 K(high_wmark_pages(zone)),
Rik van Riel4f98a2f2008-10-18 20:26:32 -07002244 K(zone_page_state(zone, NR_ACTIVE_ANON)),
2245 K(zone_page_state(zone, NR_INACTIVE_ANON)),
2246 K(zone_page_state(zone, NR_ACTIVE_FILE)),
2247 K(zone_page_state(zone, NR_INACTIVE_FILE)),
Lee Schermerhorn7b854122008-10-18 20:26:40 -07002248 K(zone_page_state(zone, NR_UNEVICTABLE)),
KOSAKI Motohiroa7312862009-09-21 17:01:37 -07002249 K(zone_page_state(zone, NR_ISOLATED_ANON)),
2250 K(zone_page_state(zone, NR_ISOLATED_FILE)),
Linus Torvalds1da177e2005-04-16 15:20:36 -07002251 K(zone->present_pages),
KOSAKI Motohiro4a0aa732009-09-21 17:01:30 -07002252 K(zone_page_state(zone, NR_MLOCK)),
2253 K(zone_page_state(zone, NR_FILE_DIRTY)),
2254 K(zone_page_state(zone, NR_WRITEBACK)),
2255 K(zone_page_state(zone, NR_FILE_MAPPED)),
KOSAKI Motohiro4b021082009-09-21 17:01:33 -07002256 K(zone_page_state(zone, NR_SHMEM)),
KOSAKI Motohiro4a0aa732009-09-21 17:01:30 -07002257 K(zone_page_state(zone, NR_SLAB_RECLAIMABLE)),
2258 K(zone_page_state(zone, NR_SLAB_UNRECLAIMABLE)),
KOSAKI Motohiroc6a7f572009-09-21 17:01:32 -07002259 zone_page_state(zone, NR_KERNEL_STACK) *
2260 THREAD_SIZE / 1024,
KOSAKI Motohiro4a0aa732009-09-21 17:01:30 -07002261 K(zone_page_state(zone, NR_PAGETABLE)),
2262 K(zone_page_state(zone, NR_UNSTABLE_NFS)),
2263 K(zone_page_state(zone, NR_BOUNCE)),
2264 K(zone_page_state(zone, NR_WRITEBACK_TEMP)),
Linus Torvalds1da177e2005-04-16 15:20:36 -07002265 zone->pages_scanned,
David Rientjese815af92007-10-16 23:25:54 -07002266 (zone_is_all_unreclaimable(zone) ? "yes" : "no")
Linus Torvalds1da177e2005-04-16 15:20:36 -07002267 );
2268 printk("lowmem_reserve[]:");
2269 for (i = 0; i < MAX_NR_ZONES; i++)
2270 printk(" %lu", zone->lowmem_reserve[i]);
2271 printk("\n");
2272 }
2273
KOSAKI Motohiroee99c712009-03-31 15:19:31 -07002274 for_each_populated_zone(zone) {
Kirill Korotaev8f9de512006-06-23 02:03:50 -07002275 unsigned long nr[MAX_ORDER], flags, order, total = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002276
2277 show_node(zone);
2278 printk("%s: ", zone->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002279
2280 spin_lock_irqsave(&zone->lock, flags);
2281 for (order = 0; order < MAX_ORDER; order++) {
Kirill Korotaev8f9de512006-06-23 02:03:50 -07002282 nr[order] = zone->free_area[order].nr_free;
2283 total += nr[order] << order;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002284 }
2285 spin_unlock_irqrestore(&zone->lock, flags);
Kirill Korotaev8f9de512006-06-23 02:03:50 -07002286 for (order = 0; order < MAX_ORDER; order++)
2287 printk("%lu*%lukB ", nr[order], K(1UL) << order);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002288 printk("= %lukB\n", K(total));
2289 }
2290
Larry Woodmane6f36022008-02-04 22:29:30 -08002291 printk("%ld total pagecache pages\n", global_page_state(NR_FILE_PAGES));
2292
Linus Torvalds1da177e2005-04-16 15:20:36 -07002293 show_swap_cache_info();
2294}
2295
Mel Gorman19770b32008-04-28 02:12:18 -07002296static void zoneref_set_zone(struct zone *zone, struct zoneref *zoneref)
2297{
2298 zoneref->zone = zone;
2299 zoneref->zone_idx = zone_idx(zone);
2300}
2301
Linus Torvalds1da177e2005-04-16 15:20:36 -07002302/*
2303 * Builds allocation fallback zone lists.
Christoph Lameter1a932052006-01-06 00:11:16 -08002304 *
2305 * Add all populated zones of a node to the zonelist.
Linus Torvalds1da177e2005-04-16 15:20:36 -07002306 */
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002307static int build_zonelists_node(pg_data_t *pgdat, struct zonelist *zonelist,
2308 int nr_zones, enum zone_type zone_type)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002309{
Christoph Lameter1a932052006-01-06 00:11:16 -08002310 struct zone *zone;
2311
Christoph Lameter98d2b0e2006-09-25 23:31:12 -07002312 BUG_ON(zone_type >= MAX_NR_ZONES);
Christoph Lameter2f6726e2006-09-25 23:31:18 -07002313 zone_type++;
Christoph Lameter02a68a52006-01-06 00:11:18 -08002314
2315 do {
Christoph Lameter2f6726e2006-09-25 23:31:18 -07002316 zone_type--;
Christoph Lameter070f8032006-01-06 00:11:19 -08002317 zone = pgdat->node_zones + zone_type;
Christoph Lameter1a932052006-01-06 00:11:16 -08002318 if (populated_zone(zone)) {
Mel Gormandd1a2392008-04-28 02:12:17 -07002319 zoneref_set_zone(zone,
2320 &zonelist->_zonerefs[nr_zones++]);
Christoph Lameter070f8032006-01-06 00:11:19 -08002321 check_highest_zone(zone_type);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002322 }
Christoph Lameter02a68a52006-01-06 00:11:18 -08002323
Christoph Lameter2f6726e2006-09-25 23:31:18 -07002324 } while (zone_type);
Christoph Lameter070f8032006-01-06 00:11:19 -08002325 return nr_zones;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002326}
2327
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002328
2329/*
2330 * zonelist_order:
2331 * 0 = automatic detection of better ordering.
2332 * 1 = order by ([node] distance, -zonetype)
2333 * 2 = order by (-zonetype, [node] distance)
2334 *
2335 * If not NUMA, ZONELIST_ORDER_ZONE and ZONELIST_ORDER_NODE will create
2336 * the same zonelist. So only NUMA can configure this param.
2337 */
2338#define ZONELIST_ORDER_DEFAULT 0
2339#define ZONELIST_ORDER_NODE 1
2340#define ZONELIST_ORDER_ZONE 2
2341
2342/* zonelist order in the kernel.
2343 * set_zonelist_order() will set this to NODE or ZONE.
2344 */
2345static int current_zonelist_order = ZONELIST_ORDER_DEFAULT;
2346static char zonelist_order_name[3][8] = {"Default", "Node", "Zone"};
2347
2348
Linus Torvalds1da177e2005-04-16 15:20:36 -07002349#ifdef CONFIG_NUMA
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002350/* The value user specified ....changed by config */
2351static int user_zonelist_order = ZONELIST_ORDER_DEFAULT;
2352/* string for sysctl */
2353#define NUMA_ZONELIST_ORDER_LEN 16
2354char numa_zonelist_order[16] = "default";
2355
2356/*
2357 * interface for configure zonelist ordering.
2358 * command line option "numa_zonelist_order"
2359 * = "[dD]efault - default, automatic configuration.
2360 * = "[nN]ode - order by node locality, then by zone within node
2361 * = "[zZ]one - order by zone, then by locality within zone
2362 */
2363
2364static int __parse_numa_zonelist_order(char *s)
2365{
2366 if (*s == 'd' || *s == 'D') {
2367 user_zonelist_order = ZONELIST_ORDER_DEFAULT;
2368 } else if (*s == 'n' || *s == 'N') {
2369 user_zonelist_order = ZONELIST_ORDER_NODE;
2370 } else if (*s == 'z' || *s == 'Z') {
2371 user_zonelist_order = ZONELIST_ORDER_ZONE;
2372 } else {
2373 printk(KERN_WARNING
2374 "Ignoring invalid numa_zonelist_order value: "
2375 "%s\n", s);
2376 return -EINVAL;
2377 }
2378 return 0;
2379}
2380
2381static __init int setup_numa_zonelist_order(char *s)
2382{
2383 if (s)
2384 return __parse_numa_zonelist_order(s);
2385 return 0;
2386}
2387early_param("numa_zonelist_order", setup_numa_zonelist_order);
2388
2389/*
2390 * sysctl handler for numa_zonelist_order
2391 */
2392int numa_zonelist_order_handler(ctl_table *table, int write,
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07002393 void __user *buffer, size_t *length,
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002394 loff_t *ppos)
2395{
2396 char saved_string[NUMA_ZONELIST_ORDER_LEN];
2397 int ret;
2398
2399 if (write)
2400 strncpy(saved_string, (char*)table->data,
2401 NUMA_ZONELIST_ORDER_LEN);
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07002402 ret = proc_dostring(table, write, buffer, length, ppos);
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002403 if (ret)
2404 return ret;
2405 if (write) {
2406 int oldval = user_zonelist_order;
2407 if (__parse_numa_zonelist_order((char*)table->data)) {
2408 /*
2409 * bogus value. restore saved string
2410 */
2411 strncpy((char*)table->data, saved_string,
2412 NUMA_ZONELIST_ORDER_LEN);
2413 user_zonelist_order = oldval;
2414 } else if (oldval != user_zonelist_order)
2415 build_all_zonelists();
2416 }
2417 return 0;
2418}
2419
2420
Christoph Lameter62bc62a2009-06-16 15:32:15 -07002421#define MAX_NODE_LOAD (nr_online_nodes)
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002422static int node_load[MAX_NUMNODES];
2423
Linus Torvalds1da177e2005-04-16 15:20:36 -07002424/**
Pavel Pisa4dc3b162005-05-01 08:59:25 -07002425 * 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 -07002426 * @node: node whose fallback list we're appending
2427 * @used_node_mask: nodemask_t of already used nodes
2428 *
2429 * We use a number of factors to determine which is the next node that should
2430 * appear on a given node's fallback list. The node should not have appeared
2431 * already in @node's fallback list, and it should be the next closest node
2432 * according to the distance array (which contains arbitrary distance values
2433 * from each node to each node in the system), and should also prefer nodes
2434 * with no CPUs, since presumably they'll have very little allocation pressure
2435 * on them otherwise.
2436 * It returns -1 if no node is found.
2437 */
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002438static int find_next_best_node(int node, nodemask_t *used_node_mask)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002439{
Linus Torvalds4cf808e2006-02-17 20:38:21 +01002440 int n, val;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002441 int min_val = INT_MAX;
2442 int best_node = -1;
Rusty Russella70f7302009-03-13 14:49:46 +10302443 const struct cpumask *tmp = cpumask_of_node(0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002444
Linus Torvalds4cf808e2006-02-17 20:38:21 +01002445 /* Use the local node if we haven't already */
2446 if (!node_isset(node, *used_node_mask)) {
2447 node_set(node, *used_node_mask);
2448 return node;
2449 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002450
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07002451 for_each_node_state(n, N_HIGH_MEMORY) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002452
2453 /* Don't want a node to appear more than once */
2454 if (node_isset(n, *used_node_mask))
2455 continue;
2456
Linus Torvalds1da177e2005-04-16 15:20:36 -07002457 /* Use the distance array to find the distance */
2458 val = node_distance(node, n);
2459
Linus Torvalds4cf808e2006-02-17 20:38:21 +01002460 /* Penalize nodes under us ("prefer the next node") */
2461 val += (n < node);
2462
Linus Torvalds1da177e2005-04-16 15:20:36 -07002463 /* Give preference to headless and unused nodes */
Rusty Russella70f7302009-03-13 14:49:46 +10302464 tmp = cpumask_of_node(n);
2465 if (!cpumask_empty(tmp))
Linus Torvalds1da177e2005-04-16 15:20:36 -07002466 val += PENALTY_FOR_NODE_WITH_CPUS;
2467
2468 /* Slight preference for less loaded node */
2469 val *= (MAX_NODE_LOAD*MAX_NUMNODES);
2470 val += node_load[n];
2471
2472 if (val < min_val) {
2473 min_val = val;
2474 best_node = n;
2475 }
2476 }
2477
2478 if (best_node >= 0)
2479 node_set(best_node, *used_node_mask);
2480
2481 return best_node;
2482}
2483
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002484
2485/*
2486 * Build zonelists ordered by node and zones within node.
2487 * This results in maximum locality--normal zone overflows into local
2488 * DMA zone, if any--but risks exhausting DMA zone.
2489 */
2490static void build_zonelists_in_node_order(pg_data_t *pgdat, int node)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002491{
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002492 int j;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002493 struct zonelist *zonelist;
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002494
Mel Gorman54a6eb52008-04-28 02:12:16 -07002495 zonelist = &pgdat->node_zonelists[0];
Mel Gormandd1a2392008-04-28 02:12:17 -07002496 for (j = 0; zonelist->_zonerefs[j].zone != NULL; j++)
Mel Gorman54a6eb52008-04-28 02:12:16 -07002497 ;
2498 j = build_zonelists_node(NODE_DATA(node), zonelist, j,
2499 MAX_NR_ZONES - 1);
Mel Gormandd1a2392008-04-28 02:12:17 -07002500 zonelist->_zonerefs[j].zone = NULL;
2501 zonelist->_zonerefs[j].zone_idx = 0;
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002502}
2503
2504/*
Christoph Lameter523b9452007-10-16 01:25:37 -07002505 * Build gfp_thisnode zonelists
2506 */
2507static void build_thisnode_zonelists(pg_data_t *pgdat)
2508{
Christoph Lameter523b9452007-10-16 01:25:37 -07002509 int j;
2510 struct zonelist *zonelist;
2511
Mel Gorman54a6eb52008-04-28 02:12:16 -07002512 zonelist = &pgdat->node_zonelists[1];
2513 j = build_zonelists_node(pgdat, zonelist, 0, MAX_NR_ZONES - 1);
Mel Gormandd1a2392008-04-28 02:12:17 -07002514 zonelist->_zonerefs[j].zone = NULL;
2515 zonelist->_zonerefs[j].zone_idx = 0;
Christoph Lameter523b9452007-10-16 01:25:37 -07002516}
2517
2518/*
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002519 * Build zonelists ordered by zone and nodes within zones.
2520 * This results in conserving DMA zone[s] until all Normal memory is
2521 * exhausted, but results in overflowing to remote node while memory
2522 * may still exist in local DMA zone.
2523 */
2524static int node_order[MAX_NUMNODES];
2525
2526static void build_zonelists_in_zone_order(pg_data_t *pgdat, int nr_nodes)
2527{
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002528 int pos, j, node;
2529 int zone_type; /* needs to be signed */
2530 struct zone *z;
2531 struct zonelist *zonelist;
2532
Mel Gorman54a6eb52008-04-28 02:12:16 -07002533 zonelist = &pgdat->node_zonelists[0];
2534 pos = 0;
2535 for (zone_type = MAX_NR_ZONES - 1; zone_type >= 0; zone_type--) {
2536 for (j = 0; j < nr_nodes; j++) {
2537 node = node_order[j];
2538 z = &NODE_DATA(node)->node_zones[zone_type];
2539 if (populated_zone(z)) {
Mel Gormandd1a2392008-04-28 02:12:17 -07002540 zoneref_set_zone(z,
2541 &zonelist->_zonerefs[pos++]);
Mel Gorman54a6eb52008-04-28 02:12:16 -07002542 check_highest_zone(zone_type);
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002543 }
2544 }
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002545 }
Mel Gormandd1a2392008-04-28 02:12:17 -07002546 zonelist->_zonerefs[pos].zone = NULL;
2547 zonelist->_zonerefs[pos].zone_idx = 0;
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002548}
2549
2550static int default_zonelist_order(void)
2551{
2552 int nid, zone_type;
2553 unsigned long low_kmem_size,total_size;
2554 struct zone *z;
2555 int average_size;
2556 /*
2557 * ZONE_DMA and ZONE_DMA32 can be very small area in the sytem.
2558 * If they are really small and used heavily, the system can fall
2559 * into OOM very easily.
2560 * This function detect ZONE_DMA/DMA32 size and confgigures zone order.
2561 */
2562 /* Is there ZONE_NORMAL ? (ex. ppc has only DMA zone..) */
2563 low_kmem_size = 0;
2564 total_size = 0;
2565 for_each_online_node(nid) {
2566 for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++) {
2567 z = &NODE_DATA(nid)->node_zones[zone_type];
2568 if (populated_zone(z)) {
2569 if (zone_type < ZONE_NORMAL)
2570 low_kmem_size += z->present_pages;
2571 total_size += z->present_pages;
2572 }
2573 }
2574 }
2575 if (!low_kmem_size || /* there are no DMA area. */
2576 low_kmem_size > total_size/2) /* DMA/DMA32 is big. */
2577 return ZONELIST_ORDER_NODE;
2578 /*
2579 * look into each node's config.
2580 * If there is a node whose DMA/DMA32 memory is very big area on
2581 * local memory, NODE_ORDER may be suitable.
2582 */
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07002583 average_size = total_size /
2584 (nodes_weight(node_states[N_HIGH_MEMORY]) + 1);
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002585 for_each_online_node(nid) {
2586 low_kmem_size = 0;
2587 total_size = 0;
2588 for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++) {
2589 z = &NODE_DATA(nid)->node_zones[zone_type];
2590 if (populated_zone(z)) {
2591 if (zone_type < ZONE_NORMAL)
2592 low_kmem_size += z->present_pages;
2593 total_size += z->present_pages;
2594 }
2595 }
2596 if (low_kmem_size &&
2597 total_size > average_size && /* ignore small node */
2598 low_kmem_size > total_size * 70/100)
2599 return ZONELIST_ORDER_NODE;
2600 }
2601 return ZONELIST_ORDER_ZONE;
2602}
2603
2604static void set_zonelist_order(void)
2605{
2606 if (user_zonelist_order == ZONELIST_ORDER_DEFAULT)
2607 current_zonelist_order = default_zonelist_order();
2608 else
2609 current_zonelist_order = user_zonelist_order;
2610}
2611
2612static void build_zonelists(pg_data_t *pgdat)
2613{
2614 int j, node, load;
2615 enum zone_type i;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002616 nodemask_t used_mask;
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002617 int local_node, prev_node;
2618 struct zonelist *zonelist;
2619 int order = current_zonelist_order;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002620
2621 /* initialize zonelists */
Christoph Lameter523b9452007-10-16 01:25:37 -07002622 for (i = 0; i < MAX_ZONELISTS; i++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002623 zonelist = pgdat->node_zonelists + i;
Mel Gormandd1a2392008-04-28 02:12:17 -07002624 zonelist->_zonerefs[0].zone = NULL;
2625 zonelist->_zonerefs[0].zone_idx = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002626 }
2627
2628 /* NUMA-aware ordering of nodes */
2629 local_node = pgdat->node_id;
Christoph Lameter62bc62a2009-06-16 15:32:15 -07002630 load = nr_online_nodes;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002631 prev_node = local_node;
2632 nodes_clear(used_mask);
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002633
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002634 memset(node_order, 0, sizeof(node_order));
2635 j = 0;
2636
Linus Torvalds1da177e2005-04-16 15:20:36 -07002637 while ((node = find_next_best_node(local_node, &used_mask)) >= 0) {
Christoph Lameter9eeff232006-01-18 17:42:31 -08002638 int distance = node_distance(local_node, node);
2639
2640 /*
2641 * If another node is sufficiently far away then it is better
2642 * to reclaim pages in a zone before going off node.
2643 */
2644 if (distance > RECLAIM_DISTANCE)
2645 zone_reclaim_mode = 1;
2646
Linus Torvalds1da177e2005-04-16 15:20:36 -07002647 /*
2648 * We don't want to pressure a particular node.
2649 * So adding penalty to the first node in same
2650 * distance group to make it round-robin.
2651 */
Christoph Lameter9eeff232006-01-18 17:42:31 -08002652 if (distance != node_distance(local_node, prev_node))
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002653 node_load[node] = load;
2654
Linus Torvalds1da177e2005-04-16 15:20:36 -07002655 prev_node = node;
2656 load--;
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002657 if (order == ZONELIST_ORDER_NODE)
2658 build_zonelists_in_node_order(pgdat, node);
2659 else
2660 node_order[j++] = node; /* remember order */
2661 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002662
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002663 if (order == ZONELIST_ORDER_ZONE) {
2664 /* calculate node order -- i.e., DMA last! */
2665 build_zonelists_in_zone_order(pgdat, j);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002666 }
Christoph Lameter523b9452007-10-16 01:25:37 -07002667
2668 build_thisnode_zonelists(pgdat);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002669}
2670
Paul Jackson9276b1bc2006-12-06 20:31:48 -08002671/* Construct the zonelist performance cache - see further mmzone.h */
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002672static void build_zonelist_cache(pg_data_t *pgdat)
Paul Jackson9276b1bc2006-12-06 20:31:48 -08002673{
Mel Gorman54a6eb52008-04-28 02:12:16 -07002674 struct zonelist *zonelist;
2675 struct zonelist_cache *zlc;
Mel Gormandd1a2392008-04-28 02:12:17 -07002676 struct zoneref *z;
Paul Jackson9276b1bc2006-12-06 20:31:48 -08002677
Mel Gorman54a6eb52008-04-28 02:12:16 -07002678 zonelist = &pgdat->node_zonelists[0];
2679 zonelist->zlcache_ptr = zlc = &zonelist->zlcache;
2680 bitmap_zero(zlc->fullzones, MAX_ZONES_PER_ZONELIST);
Mel Gormandd1a2392008-04-28 02:12:17 -07002681 for (z = zonelist->_zonerefs; z->zone; z++)
2682 zlc->z_to_n[z - zonelist->_zonerefs] = zonelist_node_idx(z);
Paul Jackson9276b1bc2006-12-06 20:31:48 -08002683}
2684
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002685
Linus Torvalds1da177e2005-04-16 15:20:36 -07002686#else /* CONFIG_NUMA */
2687
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002688static void set_zonelist_order(void)
2689{
2690 current_zonelist_order = ZONELIST_ORDER_ZONE;
2691}
2692
2693static void build_zonelists(pg_data_t *pgdat)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002694{
Christoph Lameter19655d32006-09-25 23:31:19 -07002695 int node, local_node;
Mel Gorman54a6eb52008-04-28 02:12:16 -07002696 enum zone_type j;
2697 struct zonelist *zonelist;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002698
2699 local_node = pgdat->node_id;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002700
Mel Gorman54a6eb52008-04-28 02:12:16 -07002701 zonelist = &pgdat->node_zonelists[0];
2702 j = build_zonelists_node(pgdat, zonelist, 0, MAX_NR_ZONES - 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002703
Mel Gorman54a6eb52008-04-28 02:12:16 -07002704 /*
2705 * Now we build the zonelist so that it contains the zones
2706 * of all the other nodes.
2707 * We don't want to pressure a particular node, so when
2708 * building the zones for node N, we make sure that the
2709 * zones coming right after the local ones are those from
2710 * node N+1 (modulo N)
2711 */
2712 for (node = local_node + 1; node < MAX_NUMNODES; node++) {
2713 if (!node_online(node))
2714 continue;
2715 j = build_zonelists_node(NODE_DATA(node), zonelist, j,
2716 MAX_NR_ZONES - 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002717 }
Mel Gorman54a6eb52008-04-28 02:12:16 -07002718 for (node = 0; node < local_node; node++) {
2719 if (!node_online(node))
2720 continue;
2721 j = build_zonelists_node(NODE_DATA(node), zonelist, j,
2722 MAX_NR_ZONES - 1);
2723 }
2724
Mel Gormandd1a2392008-04-28 02:12:17 -07002725 zonelist->_zonerefs[j].zone = NULL;
2726 zonelist->_zonerefs[j].zone_idx = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002727}
2728
Paul Jackson9276b1bc2006-12-06 20:31:48 -08002729/* non-NUMA variant of zonelist performance cache - just NULL zlcache_ptr */
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002730static void build_zonelist_cache(pg_data_t *pgdat)
Paul Jackson9276b1bc2006-12-06 20:31:48 -08002731{
Mel Gorman54a6eb52008-04-28 02:12:16 -07002732 pgdat->node_zonelists[0].zlcache_ptr = NULL;
Paul Jackson9276b1bc2006-12-06 20:31:48 -08002733}
2734
Linus Torvalds1da177e2005-04-16 15:20:36 -07002735#endif /* CONFIG_NUMA */
2736
Rusty Russell9b1a4d32008-07-28 12:16:30 -05002737/* return values int ....just for stop_machine() */
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002738static int __build_all_zonelists(void *dummy)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002739{
Yasunori Goto68113782006-06-23 02:03:11 -07002740 int nid;
Paul Jackson9276b1bc2006-12-06 20:31:48 -08002741
Bo Liu7f9cfb32009-08-18 14:11:19 -07002742#ifdef CONFIG_NUMA
2743 memset(node_load, 0, sizeof(node_load));
2744#endif
Paul Jackson9276b1bc2006-12-06 20:31:48 -08002745 for_each_online_node(nid) {
Christoph Lameter7ea15302007-10-16 01:25:29 -07002746 pg_data_t *pgdat = NODE_DATA(nid);
2747
2748 build_zonelists(pgdat);
2749 build_zonelist_cache(pgdat);
Paul Jackson9276b1bc2006-12-06 20:31:48 -08002750 }
Yasunori Goto68113782006-06-23 02:03:11 -07002751 return 0;
2752}
Linus Torvalds1da177e2005-04-16 15:20:36 -07002753
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002754void build_all_zonelists(void)
Yasunori Goto68113782006-06-23 02:03:11 -07002755{
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002756 set_zonelist_order();
2757
Yasunori Goto68113782006-06-23 02:03:11 -07002758 if (system_state == SYSTEM_BOOTING) {
Randy Dunlap423b41d2006-09-27 01:50:12 -07002759 __build_all_zonelists(NULL);
Mel Gorman68ad8df2008-07-23 21:26:52 -07002760 mminit_verify_zonelist();
Yasunori Goto68113782006-06-23 02:03:11 -07002761 cpuset_init_current_mems_allowed();
2762 } else {
Simon Arlott183ff222007-10-20 01:27:18 +02002763 /* we have to stop all cpus to guarantee there is no user
Yasunori Goto68113782006-06-23 02:03:11 -07002764 of zonelist */
Rusty Russell9b1a4d32008-07-28 12:16:30 -05002765 stop_machine(__build_all_zonelists, NULL, NULL);
Yasunori Goto68113782006-06-23 02:03:11 -07002766 /* cpuset refresh routine should be here */
2767 }
Andrew Mortonbd1e22b2006-06-23 02:03:47 -07002768 vm_total_pages = nr_free_pagecache_pages();
Mel Gorman9ef9acb2007-10-16 01:25:54 -07002769 /*
2770 * Disable grouping by mobility if the number of pages in the
2771 * system is too low to allow the mechanism to work. It would be
2772 * more accurate, but expensive to check per-zone. This check is
2773 * made on memory-hotadd so a system can start with mobility
2774 * disabled and enable it later
2775 */
Mel Gormand9c23402007-10-16 01:26:01 -07002776 if (vm_total_pages < (pageblock_nr_pages * MIGRATE_TYPES))
Mel Gorman9ef9acb2007-10-16 01:25:54 -07002777 page_group_by_mobility_disabled = 1;
2778 else
2779 page_group_by_mobility_disabled = 0;
2780
2781 printk("Built %i zonelists in %s order, mobility grouping %s. "
2782 "Total pages: %ld\n",
Christoph Lameter62bc62a2009-06-16 15:32:15 -07002783 nr_online_nodes,
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002784 zonelist_order_name[current_zonelist_order],
Mel Gorman9ef9acb2007-10-16 01:25:54 -07002785 page_group_by_mobility_disabled ? "off" : "on",
KAMEZAWA Hiroyukif0c0b2b2007-07-15 23:38:01 -07002786 vm_total_pages);
2787#ifdef CONFIG_NUMA
2788 printk("Policy zone: %s\n", zone_names[policy_zone]);
2789#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07002790}
2791
2792/*
2793 * Helper functions to size the waitqueue hash table.
2794 * Essentially these want to choose hash table sizes sufficiently
2795 * large so that collisions trying to wait on pages are rare.
2796 * But in fact, the number of active page waitqueues on typical
2797 * systems is ridiculously low, less than 200. So this is even
2798 * conservative, even though it seems large.
2799 *
2800 * The constant PAGES_PER_WAITQUEUE specifies the ratio of pages to
2801 * waitqueues, i.e. the size of the waitq table given the number of pages.
2802 */
2803#define PAGES_PER_WAITQUEUE 256
2804
Yasunori Gotocca448f2006-06-23 02:03:10 -07002805#ifndef CONFIG_MEMORY_HOTPLUG
Yasunori Goto02b694d2006-06-23 02:03:08 -07002806static inline unsigned long wait_table_hash_nr_entries(unsigned long pages)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002807{
2808 unsigned long size = 1;
2809
2810 pages /= PAGES_PER_WAITQUEUE;
2811
2812 while (size < pages)
2813 size <<= 1;
2814
2815 /*
2816 * Once we have dozens or even hundreds of threads sleeping
2817 * on IO we've got bigger problems than wait queue collision.
2818 * Limit the size of the wait table to a reasonable size.
2819 */
2820 size = min(size, 4096UL);
2821
2822 return max(size, 4UL);
2823}
Yasunori Gotocca448f2006-06-23 02:03:10 -07002824#else
2825/*
2826 * A zone's size might be changed by hot-add, so it is not possible to determine
2827 * a suitable size for its wait_table. So we use the maximum size now.
2828 *
2829 * The max wait table size = 4096 x sizeof(wait_queue_head_t). ie:
2830 *
2831 * i386 (preemption config) : 4096 x 16 = 64Kbyte.
2832 * ia64, x86-64 (no preemption): 4096 x 20 = 80Kbyte.
2833 * ia64, x86-64 (preemption) : 4096 x 24 = 96Kbyte.
2834 *
2835 * The maximum entries are prepared when a zone's memory is (512K + 256) pages
2836 * or more by the traditional way. (See above). It equals:
2837 *
2838 * i386, x86-64, powerpc(4K page size) : = ( 2G + 1M)byte.
2839 * ia64(16K page size) : = ( 8G + 4M)byte.
2840 * powerpc (64K page size) : = (32G +16M)byte.
2841 */
2842static inline unsigned long wait_table_hash_nr_entries(unsigned long pages)
2843{
2844 return 4096UL;
2845}
2846#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07002847
2848/*
2849 * This is an integer logarithm so that shifts can be used later
2850 * to extract the more random high bits from the multiplicative
2851 * hash function before the remainder is taken.
2852 */
2853static inline unsigned long wait_table_bits(unsigned long size)
2854{
2855 return ffz(~size);
2856}
2857
2858#define LONG_ALIGN(x) (((x)+(sizeof(long))-1)&~((sizeof(long))-1))
2859
Mel Gorman56fd56b2007-10-16 01:25:58 -07002860/*
Mel Gormand9c23402007-10-16 01:26:01 -07002861 * Mark a number of pageblocks as MIGRATE_RESERVE. The number
Mel Gorman41858962009-06-16 15:32:12 -07002862 * of blocks reserved is based on min_wmark_pages(zone). The memory within
2863 * the reserve will tend to store contiguous free pages. Setting min_free_kbytes
Mel Gorman56fd56b2007-10-16 01:25:58 -07002864 * higher will lead to a bigger reserve which will get freed as contiguous
2865 * blocks as reclaim kicks in
2866 */
2867static void setup_zone_migrate_reserve(struct zone *zone)
2868{
2869 unsigned long start_pfn, pfn, end_pfn;
2870 struct page *page;
Mel Gorman78986a62009-09-21 17:03:02 -07002871 unsigned long block_migratetype;
2872 int reserve;
Mel Gorman56fd56b2007-10-16 01:25:58 -07002873
2874 /* Get the start pfn, end pfn and the number of blocks to reserve */
2875 start_pfn = zone->zone_start_pfn;
2876 end_pfn = start_pfn + zone->spanned_pages;
Mel Gorman41858962009-06-16 15:32:12 -07002877 reserve = roundup(min_wmark_pages(zone), pageblock_nr_pages) >>
Mel Gormand9c23402007-10-16 01:26:01 -07002878 pageblock_order;
Mel Gorman56fd56b2007-10-16 01:25:58 -07002879
Mel Gorman78986a62009-09-21 17:03:02 -07002880 /*
2881 * Reserve blocks are generally in place to help high-order atomic
2882 * allocations that are short-lived. A min_free_kbytes value that
2883 * would result in more than 2 reserve blocks for atomic allocations
2884 * is assumed to be in place to help anti-fragmentation for the
2885 * future allocation of hugepages at runtime.
2886 */
2887 reserve = min(2, reserve);
2888
Mel Gormand9c23402007-10-16 01:26:01 -07002889 for (pfn = start_pfn; pfn < end_pfn; pfn += pageblock_nr_pages) {
Mel Gorman56fd56b2007-10-16 01:25:58 -07002890 if (!pfn_valid(pfn))
2891 continue;
2892 page = pfn_to_page(pfn);
2893
Adam Litke344c7902008-09-02 14:35:38 -07002894 /* Watch out for overlapping nodes */
2895 if (page_to_nid(page) != zone_to_nid(zone))
2896 continue;
2897
Mel Gorman56fd56b2007-10-16 01:25:58 -07002898 /* Blocks with reserved pages will never free, skip them. */
2899 if (PageReserved(page))
2900 continue;
2901
2902 block_migratetype = get_pageblock_migratetype(page);
2903
2904 /* If this block is reserved, account for it */
2905 if (reserve > 0 && block_migratetype == MIGRATE_RESERVE) {
2906 reserve--;
2907 continue;
2908 }
2909
2910 /* Suitable for reserving if this block is movable */
2911 if (reserve > 0 && block_migratetype == MIGRATE_MOVABLE) {
2912 set_pageblock_migratetype(page, MIGRATE_RESERVE);
2913 move_freepages_block(zone, page, MIGRATE_RESERVE);
2914 reserve--;
2915 continue;
2916 }
2917
2918 /*
2919 * If the reserve is met and this is a previous reserved block,
2920 * take it back
2921 */
2922 if (block_migratetype == MIGRATE_RESERVE) {
2923 set_pageblock_migratetype(page, MIGRATE_MOVABLE);
2924 move_freepages_block(zone, page, MIGRATE_MOVABLE);
2925 }
2926 }
2927}
Mel Gormanac0e5b72007-10-16 01:25:58 -07002928
Linus Torvalds1da177e2005-04-16 15:20:36 -07002929/*
2930 * Initially all pages are reserved - free ones are freed
2931 * up by free_all_bootmem() once the early boot process is
2932 * done. Non-atomic initialization, single-pass.
2933 */
Matt Tolentinoc09b4242006-01-17 07:03:44 +01002934void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone,
Dave Hansena2f3aa02007-01-10 23:15:30 -08002935 unsigned long start_pfn, enum memmap_context context)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002936{
Linus Torvalds1da177e2005-04-16 15:20:36 -07002937 struct page *page;
Andy Whitcroft29751f62005-06-23 00:08:00 -07002938 unsigned long end_pfn = start_pfn + size;
2939 unsigned long pfn;
KAMEZAWA Hiroyuki86051ca2008-04-29 00:58:21 -07002940 struct zone *z;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002941
Hugh Dickins22b31ee2009-01-06 14:40:09 -08002942 if (highest_memmap_pfn < end_pfn - 1)
2943 highest_memmap_pfn = end_pfn - 1;
2944
KAMEZAWA Hiroyuki86051ca2008-04-29 00:58:21 -07002945 z = &NODE_DATA(nid)->node_zones[zone];
Greg Ungerercbe8dd42006-01-12 01:05:24 -08002946 for (pfn = start_pfn; pfn < end_pfn; pfn++) {
Dave Hansena2f3aa02007-01-10 23:15:30 -08002947 /*
2948 * There can be holes in boot-time mem_map[]s
2949 * handed to this function. They do not
2950 * exist on hotplugged memory.
2951 */
2952 if (context == MEMMAP_EARLY) {
2953 if (!early_pfn_valid(pfn))
2954 continue;
2955 if (!early_pfn_in_nid(pfn, nid))
2956 continue;
2957 }
Andy Whitcroftd41dee32005-06-23 00:07:54 -07002958 page = pfn_to_page(pfn);
2959 set_page_links(page, zone, nid, pfn);
Mel Gorman708614e2008-07-23 21:26:51 -07002960 mminit_verify_page_links(page, zone, nid, pfn);
Nick Piggin7835e982006-03-22 00:08:40 -08002961 init_page_count(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002962 reset_page_mapcount(page);
2963 SetPageReserved(page);
Mel Gormanb2a0ac82007-10-16 01:25:48 -07002964 /*
2965 * Mark the block movable so that blocks are reserved for
2966 * movable at startup. This will force kernel allocations
2967 * to reserve their blocks rather than leaking throughout
2968 * the address space during boot when many long-lived
Mel Gorman56fd56b2007-10-16 01:25:58 -07002969 * kernel allocations are made. Later some blocks near
2970 * the start are marked MIGRATE_RESERVE by
2971 * setup_zone_migrate_reserve()
KAMEZAWA Hiroyuki86051ca2008-04-29 00:58:21 -07002972 *
2973 * bitmap is created for zone's valid pfn range. but memmap
2974 * can be created for invalid pages (for alignment)
2975 * check here not to call set_pageblock_migratetype() against
2976 * pfn out of zone.
Mel Gormanb2a0ac82007-10-16 01:25:48 -07002977 */
KAMEZAWA Hiroyuki86051ca2008-04-29 00:58:21 -07002978 if ((z->zone_start_pfn <= pfn)
2979 && (pfn < z->zone_start_pfn + z->spanned_pages)
2980 && !(pfn & (pageblock_nr_pages - 1)))
Mel Gorman56fd56b2007-10-16 01:25:58 -07002981 set_pageblock_migratetype(page, MIGRATE_MOVABLE);
Mel Gormanb2a0ac82007-10-16 01:25:48 -07002982
Linus Torvalds1da177e2005-04-16 15:20:36 -07002983 INIT_LIST_HEAD(&page->lru);
2984#ifdef WANT_PAGE_VIRTUAL
2985 /* The shift won't overflow because ZONE_NORMAL is below 4G. */
2986 if (!is_highmem_idx(zone))
Bob Picco3212c6b2005-06-27 14:36:28 -07002987 set_page_address(page, __va(pfn << PAGE_SHIFT));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002988#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07002989 }
2990}
2991
Andi Kleen1e548de2008-02-04 22:29:26 -08002992static void __meminit zone_init_free_lists(struct zone *zone)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002993{
Mel Gormanb2a0ac82007-10-16 01:25:48 -07002994 int order, t;
2995 for_each_migratetype_order(order, t) {
2996 INIT_LIST_HEAD(&zone->free_area[order].free_list[t]);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002997 zone->free_area[order].nr_free = 0;
2998 }
2999}
3000
3001#ifndef __HAVE_ARCH_MEMMAP_INIT
3002#define memmap_init(size, nid, zone, start_pfn) \
Dave Hansena2f3aa02007-01-10 23:15:30 -08003003 memmap_init_zone((size), (nid), (zone), (start_pfn), MEMMAP_EARLY)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003004#endif
3005
Sam Ravnborg1d6f4e62008-01-17 15:21:12 -08003006static int zone_batchsize(struct zone *zone)
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003007{
David Howells3a6be872009-05-06 16:03:03 -07003008#ifdef CONFIG_MMU
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003009 int batch;
3010
3011 /*
3012 * The per-cpu-pages pools are set to around 1000th of the
Seth, Rohitba56e912005-10-29 18:15:47 -07003013 * size of the zone. But no more than 1/2 of a meg.
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003014 *
3015 * OK, so we don't know how big the cache is. So guess.
3016 */
3017 batch = zone->present_pages / 1024;
Seth, Rohitba56e912005-10-29 18:15:47 -07003018 if (batch * PAGE_SIZE > 512 * 1024)
3019 batch = (512 * 1024) / PAGE_SIZE;
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003020 batch /= 4; /* We effectively *= 4 below */
3021 if (batch < 1)
3022 batch = 1;
3023
3024 /*
Nick Piggin0ceaacc2005-12-04 13:55:25 +11003025 * Clamp the batch to a 2^n - 1 value. Having a power
3026 * of 2 value was found to be more likely to have
3027 * suboptimal cache aliasing properties in some cases.
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003028 *
Nick Piggin0ceaacc2005-12-04 13:55:25 +11003029 * For example if 2 tasks are alternately allocating
3030 * batches of pages, one task can end up with a lot
3031 * of pages of one half of the possible page colors
3032 * and the other with pages of the other colors.
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003033 */
David Howells91552032009-05-06 16:03:02 -07003034 batch = rounddown_pow_of_two(batch + batch/2) - 1;
Seth, Rohitba56e912005-10-29 18:15:47 -07003035
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003036 return batch;
David Howells3a6be872009-05-06 16:03:03 -07003037
3038#else
3039 /* The deferral and batching of frees should be suppressed under NOMMU
3040 * conditions.
3041 *
3042 * The problem is that NOMMU needs to be able to allocate large chunks
3043 * of contiguous memory as there's no hardware page translation to
3044 * assemble apparent contiguous memory from discontiguous pages.
3045 *
3046 * Queueing large contiguous runs of pages for batching, however,
3047 * causes the pages to actually be freed in smaller chunks. As there
3048 * can be a significant delay between the individual batches being
3049 * recycled, this leads to the once large chunks of space being
3050 * fragmented and becoming unavailable for high-order allocations.
3051 */
3052 return 0;
3053#endif
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003054}
3055
Adrian Bunkb69a7282008-07-23 21:28:12 -07003056static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch)
Christoph Lameter2caaad42005-06-21 17:15:00 -07003057{
3058 struct per_cpu_pages *pcp;
Mel Gorman5f8dcc22009-09-21 17:03:19 -07003059 int migratetype;
Christoph Lameter2caaad42005-06-21 17:15:00 -07003060
Magnus Damm1c6fe942005-10-26 01:58:59 -07003061 memset(p, 0, sizeof(*p));
3062
Christoph Lameter3dfa5722008-02-04 22:29:19 -08003063 pcp = &p->pcp;
Christoph Lameter2caaad42005-06-21 17:15:00 -07003064 pcp->count = 0;
Christoph Lameter2caaad42005-06-21 17:15:00 -07003065 pcp->high = 6 * batch;
3066 pcp->batch = max(1UL, 1 * batch);
Mel Gorman5f8dcc22009-09-21 17:03:19 -07003067 for (migratetype = 0; migratetype < MIGRATE_PCPTYPES; migratetype++)
3068 INIT_LIST_HEAD(&pcp->lists[migratetype]);
Christoph Lameter2caaad42005-06-21 17:15:00 -07003069}
3070
Rohit Seth8ad4b1f2006-01-08 01:00:40 -08003071/*
3072 * setup_pagelist_highmark() sets the high water mark for hot per_cpu_pagelist
3073 * to the value high for the pageset p.
3074 */
3075
3076static void setup_pagelist_highmark(struct per_cpu_pageset *p,
3077 unsigned long high)
3078{
3079 struct per_cpu_pages *pcp;
3080
Christoph Lameter3dfa5722008-02-04 22:29:19 -08003081 pcp = &p->pcp;
Rohit Seth8ad4b1f2006-01-08 01:00:40 -08003082 pcp->high = high;
3083 pcp->batch = max(1UL, high/4);
3084 if ((high/4) > (PAGE_SHIFT * 8))
3085 pcp->batch = PAGE_SHIFT * 8;
3086}
3087
3088
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003089#ifdef CONFIG_NUMA
3090/*
Christoph Lameter2caaad42005-06-21 17:15:00 -07003091 * Boot pageset table. One per cpu which is going to be used for all
3092 * zones and all nodes. The parameters will be set in such a way
3093 * that an item put on a list will immediately be handed over to
3094 * the buddy list. This is safe since pageset manipulation is done
3095 * with interrupts disabled.
3096 *
3097 * Some NUMA counter updates may also be caught by the boot pagesets.
Christoph Lameterb7c84c62005-06-22 20:26:07 -07003098 *
3099 * The boot_pagesets must be kept even after bootup is complete for
3100 * unused processors and/or zones. They do play a role for bootstrapping
3101 * hotplugged processors.
3102 *
3103 * zoneinfo_show() and maybe other functions do
3104 * not check if the processor is online before following the pageset pointer.
3105 * Other parts of the kernel may not check if the zone is available.
Christoph Lameter2caaad42005-06-21 17:15:00 -07003106 */
Eric Dumazet88a2a4ac2006-02-04 23:27:36 -08003107static struct per_cpu_pageset boot_pageset[NR_CPUS];
Christoph Lameter2caaad42005-06-21 17:15:00 -07003108
3109/*
3110 * Dynamically allocate memory for the
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003111 * per cpu pageset array in struct zone.
3112 */
Ashok Raj6292d9a2006-02-01 03:04:44 -08003113static int __cpuinit process_zones(int cpu)
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003114{
3115 struct zone *zone, *dzone;
Christoph Lameter37c07082007-10-16 01:25:36 -07003116 int node = cpu_to_node(cpu);
3117
3118 node_set_state(node, N_CPU); /* this node has a cpu */
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003119
KOSAKI Motohiroee99c712009-03-31 15:19:31 -07003120 for_each_populated_zone(zone) {
Nick Piggin23316bc2006-01-08 01:00:41 -08003121 zone_pcp(zone, cpu) = kmalloc_node(sizeof(struct per_cpu_pageset),
Christoph Lameter37c07082007-10-16 01:25:36 -07003122 GFP_KERNEL, node);
Nick Piggin23316bc2006-01-08 01:00:41 -08003123 if (!zone_pcp(zone, cpu))
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003124 goto bad;
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003125
Nick Piggin23316bc2006-01-08 01:00:41 -08003126 setup_pageset(zone_pcp(zone, cpu), zone_batchsize(zone));
Rohit Seth8ad4b1f2006-01-08 01:00:40 -08003127
3128 if (percpu_pagelist_fraction)
3129 setup_pagelist_highmark(zone_pcp(zone, cpu),
3130 (zone->present_pages / percpu_pagelist_fraction));
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003131 }
3132
3133 return 0;
3134bad:
3135 for_each_zone(dzone) {
Andrew Morton64191682007-08-30 23:56:17 -07003136 if (!populated_zone(dzone))
3137 continue;
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003138 if (dzone == zone)
3139 break;
Nick Piggin23316bc2006-01-08 01:00:41 -08003140 kfree(zone_pcp(dzone, cpu));
Dimitri Sivanich364df0e2009-06-23 12:37:04 -07003141 zone_pcp(dzone, cpu) = &boot_pageset[cpu];
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003142 }
3143 return -ENOMEM;
3144}
3145
3146static inline void free_zone_pagesets(int cpu)
3147{
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003148 struct zone *zone;
3149
3150 for_each_zone(zone) {
3151 struct per_cpu_pageset *pset = zone_pcp(zone, cpu);
3152
David Rientjesf3ef9ea2006-09-25 16:24:57 -07003153 /* Free per_cpu_pageset if it is slab allocated */
3154 if (pset != &boot_pageset[cpu])
3155 kfree(pset);
Dimitri Sivanich364df0e2009-06-23 12:37:04 -07003156 zone_pcp(zone, cpu) = &boot_pageset[cpu];
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003157 }
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003158}
3159
Chandra Seetharaman9c7b2162006-06-27 02:54:07 -07003160static int __cpuinit pageset_cpuup_callback(struct notifier_block *nfb,
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003161 unsigned long action,
3162 void *hcpu)
3163{
3164 int cpu = (long)hcpu;
3165 int ret = NOTIFY_OK;
3166
3167 switch (action) {
Andy Whitcroftce421c72006-12-06 20:33:08 -08003168 case CPU_UP_PREPARE:
Rafael J. Wysocki8bb78442007-05-09 02:35:10 -07003169 case CPU_UP_PREPARE_FROZEN:
Andy Whitcroftce421c72006-12-06 20:33:08 -08003170 if (process_zones(cpu))
3171 ret = NOTIFY_BAD;
3172 break;
3173 case CPU_UP_CANCELED:
Rafael J. Wysocki8bb78442007-05-09 02:35:10 -07003174 case CPU_UP_CANCELED_FROZEN:
Andy Whitcroftce421c72006-12-06 20:33:08 -08003175 case CPU_DEAD:
Rafael J. Wysocki8bb78442007-05-09 02:35:10 -07003176 case CPU_DEAD_FROZEN:
Andy Whitcroftce421c72006-12-06 20:33:08 -08003177 free_zone_pagesets(cpu);
3178 break;
3179 default:
3180 break;
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003181 }
3182 return ret;
3183}
3184
Chandra Seetharaman74b85f32006-06-27 02:54:09 -07003185static struct notifier_block __cpuinitdata pageset_notifier =
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003186 { &pageset_cpuup_callback, NULL, 0 };
3187
Al Viro78d99552005-12-15 09:18:25 +00003188void __init setup_per_cpu_pageset(void)
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07003189{
3190 int err;
3191
3192 /* Initialize per_cpu_pageset for cpu 0.
3193 * A cpuup callback will do this for every cpu
3194 * as it comes online
3195 */
3196 err = process_zones(smp_processor_id());
3197 BUG_ON(err);
3198 register_cpu_notifier(&pageset_notifier);
3199}
3200
3201#endif
3202
Sam Ravnborg577a32f2007-05-17 23:29:25 +02003203static noinline __init_refok
Yasunori Gotocca448f2006-06-23 02:03:10 -07003204int zone_wait_table_init(struct zone *zone, unsigned long zone_size_pages)
Dave Hansened8ece22005-10-29 18:16:50 -07003205{
3206 int i;
3207 struct pglist_data *pgdat = zone->zone_pgdat;
Yasunori Gotocca448f2006-06-23 02:03:10 -07003208 size_t alloc_size;
Dave Hansened8ece22005-10-29 18:16:50 -07003209
3210 /*
3211 * The per-page waitqueue mechanism uses hashed waitqueues
3212 * per zone.
3213 */
Yasunori Goto02b694d2006-06-23 02:03:08 -07003214 zone->wait_table_hash_nr_entries =
3215 wait_table_hash_nr_entries(zone_size_pages);
3216 zone->wait_table_bits =
3217 wait_table_bits(zone->wait_table_hash_nr_entries);
Yasunori Gotocca448f2006-06-23 02:03:10 -07003218 alloc_size = zone->wait_table_hash_nr_entries
3219 * sizeof(wait_queue_head_t);
3220
Heiko Carstenscd94b9d2008-05-23 13:04:52 -07003221 if (!slab_is_available()) {
Yasunori Gotocca448f2006-06-23 02:03:10 -07003222 zone->wait_table = (wait_queue_head_t *)
3223 alloc_bootmem_node(pgdat, alloc_size);
3224 } else {
3225 /*
3226 * This case means that a zone whose size was 0 gets new memory
3227 * via memory hot-add.
3228 * But it may be the case that a new node was hot-added. In
3229 * this case vmalloc() will not be able to use this new node's
3230 * memory - this wait_table must be initialized to use this new
3231 * node itself as well.
3232 * To use this new node's memory, further consideration will be
3233 * necessary.
3234 */
Jesper Juhl8691f3a2007-10-16 01:24:49 -07003235 zone->wait_table = vmalloc(alloc_size);
Yasunori Gotocca448f2006-06-23 02:03:10 -07003236 }
3237 if (!zone->wait_table)
3238 return -ENOMEM;
Dave Hansened8ece22005-10-29 18:16:50 -07003239
Yasunori Goto02b694d2006-06-23 02:03:08 -07003240 for(i = 0; i < zone->wait_table_hash_nr_entries; ++i)
Dave Hansened8ece22005-10-29 18:16:50 -07003241 init_waitqueue_head(zone->wait_table + i);
Yasunori Gotocca448f2006-06-23 02:03:10 -07003242
3243 return 0;
Dave Hansened8ece22005-10-29 18:16:50 -07003244}
3245
Shaohua Li112067f2009-09-21 17:01:16 -07003246static int __zone_pcp_update(void *data)
3247{
3248 struct zone *zone = data;
3249 int cpu;
3250 unsigned long batch = zone_batchsize(zone), flags;
3251
3252 for (cpu = 0; cpu < NR_CPUS; cpu++) {
3253 struct per_cpu_pageset *pset;
3254 struct per_cpu_pages *pcp;
3255
3256 pset = zone_pcp(zone, cpu);
3257 pcp = &pset->pcp;
3258
3259 local_irq_save(flags);
Mel Gorman5f8dcc22009-09-21 17:03:19 -07003260 free_pcppages_bulk(zone, pcp->count, pcp);
Shaohua Li112067f2009-09-21 17:01:16 -07003261 setup_pageset(pset, batch);
3262 local_irq_restore(flags);
3263 }
3264 return 0;
3265}
3266
3267void zone_pcp_update(struct zone *zone)
3268{
3269 stop_machine(__zone_pcp_update, zone, NULL);
3270}
3271
Matt Tolentinoc09b4242006-01-17 07:03:44 +01003272static __meminit void zone_pcp_init(struct zone *zone)
Dave Hansened8ece22005-10-29 18:16:50 -07003273{
3274 int cpu;
3275 unsigned long batch = zone_batchsize(zone);
3276
3277 for (cpu = 0; cpu < NR_CPUS; cpu++) {
3278#ifdef CONFIG_NUMA
3279 /* Early boot. Slab allocator not functional yet */
Nick Piggin23316bc2006-01-08 01:00:41 -08003280 zone_pcp(zone, cpu) = &boot_pageset[cpu];
Dave Hansened8ece22005-10-29 18:16:50 -07003281 setup_pageset(&boot_pageset[cpu],0);
3282#else
3283 setup_pageset(zone_pcp(zone,cpu), batch);
3284#endif
3285 }
Anton Blanchardf5335c02006-03-25 03:06:49 -08003286 if (zone->present_pages)
3287 printk(KERN_DEBUG " %s zone: %lu pages, LIFO batch:%lu\n",
3288 zone->name, zone->present_pages, batch);
Dave Hansened8ece22005-10-29 18:16:50 -07003289}
3290
Yasunori Goto718127c2006-06-23 02:03:10 -07003291__meminit int init_currently_empty_zone(struct zone *zone,
3292 unsigned long zone_start_pfn,
Dave Hansena2f3aa02007-01-10 23:15:30 -08003293 unsigned long size,
3294 enum memmap_context context)
Dave Hansened8ece22005-10-29 18:16:50 -07003295{
3296 struct pglist_data *pgdat = zone->zone_pgdat;
Yasunori Gotocca448f2006-06-23 02:03:10 -07003297 int ret;
3298 ret = zone_wait_table_init(zone, size);
3299 if (ret)
3300 return ret;
Dave Hansened8ece22005-10-29 18:16:50 -07003301 pgdat->nr_zones = zone_idx(zone) + 1;
3302
Dave Hansened8ece22005-10-29 18:16:50 -07003303 zone->zone_start_pfn = zone_start_pfn;
3304
Mel Gorman708614e2008-07-23 21:26:51 -07003305 mminit_dprintk(MMINIT_TRACE, "memmap_init",
3306 "Initialising map node %d zone %lu pfns %lu -> %lu\n",
3307 pgdat->node_id,
3308 (unsigned long)zone_idx(zone),
3309 zone_start_pfn, (zone_start_pfn + size));
3310
Andi Kleen1e548de2008-02-04 22:29:26 -08003311 zone_init_free_lists(zone);
Yasunori Goto718127c2006-06-23 02:03:10 -07003312
3313 return 0;
Dave Hansened8ece22005-10-29 18:16:50 -07003314}
3315
Mel Gormanc7132162006-09-27 01:49:43 -07003316#ifdef CONFIG_ARCH_POPULATES_NODE_MAP
3317/*
3318 * Basic iterator support. Return the first range of PFNs for a node
3319 * Note: nid == MAX_NUMNODES returns first region regardless of node
3320 */
Yasunori Gotoa3142c82007-05-08 00:23:07 -07003321static int __meminit first_active_region_index_in_nid(int nid)
Mel Gormanc7132162006-09-27 01:49:43 -07003322{
3323 int i;
3324
3325 for (i = 0; i < nr_nodemap_entries; i++)
3326 if (nid == MAX_NUMNODES || early_node_map[i].nid == nid)
3327 return i;
3328
3329 return -1;
3330}
3331
3332/*
3333 * Basic iterator support. Return the next active range of PFNs for a node
Simon Arlott183ff222007-10-20 01:27:18 +02003334 * Note: nid == MAX_NUMNODES returns next region regardless of node
Mel Gormanc7132162006-09-27 01:49:43 -07003335 */
Yasunori Gotoa3142c82007-05-08 00:23:07 -07003336static int __meminit next_active_region_index_in_nid(int index, int nid)
Mel Gormanc7132162006-09-27 01:49:43 -07003337{
3338 for (index = index + 1; index < nr_nodemap_entries; index++)
3339 if (nid == MAX_NUMNODES || early_node_map[index].nid == nid)
3340 return index;
3341
3342 return -1;
3343}
3344
3345#ifndef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
3346/*
3347 * Required by SPARSEMEM. Given a PFN, return what node the PFN is on.
3348 * Architectures may implement their own version but if add_active_range()
3349 * was used and there are no special requirements, this is a convenient
3350 * alternative
3351 */
KAMEZAWA Hiroyukif2dbcfa2009-02-18 14:48:32 -08003352int __meminit __early_pfn_to_nid(unsigned long pfn)
Mel Gormanc7132162006-09-27 01:49:43 -07003353{
3354 int i;
3355
3356 for (i = 0; i < nr_nodemap_entries; i++) {
3357 unsigned long start_pfn = early_node_map[i].start_pfn;
3358 unsigned long end_pfn = early_node_map[i].end_pfn;
3359
3360 if (start_pfn <= pfn && pfn < end_pfn)
3361 return early_node_map[i].nid;
3362 }
KAMEZAWA Hiroyukicc2559b2009-02-18 14:48:33 -08003363 /* This is a memory hole */
3364 return -1;
Mel Gormanc7132162006-09-27 01:49:43 -07003365}
3366#endif /* CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID */
3367
KAMEZAWA Hiroyukif2dbcfa2009-02-18 14:48:32 -08003368int __meminit early_pfn_to_nid(unsigned long pfn)
3369{
KAMEZAWA Hiroyukicc2559b2009-02-18 14:48:33 -08003370 int nid;
3371
3372 nid = __early_pfn_to_nid(pfn);
3373 if (nid >= 0)
3374 return nid;
3375 /* just returns 0 */
3376 return 0;
KAMEZAWA Hiroyukif2dbcfa2009-02-18 14:48:32 -08003377}
3378
KAMEZAWA Hiroyukicc2559b2009-02-18 14:48:33 -08003379#ifdef CONFIG_NODES_SPAN_OTHER_NODES
3380bool __meminit early_pfn_in_nid(unsigned long pfn, int node)
3381{
3382 int nid;
3383
3384 nid = __early_pfn_to_nid(pfn);
3385 if (nid >= 0 && nid != node)
3386 return false;
3387 return true;
3388}
3389#endif
KAMEZAWA Hiroyukif2dbcfa2009-02-18 14:48:32 -08003390
Mel Gormanc7132162006-09-27 01:49:43 -07003391/* Basic iterator support to walk early_node_map[] */
3392#define for_each_active_range_index_in_nid(i, nid) \
3393 for (i = first_active_region_index_in_nid(nid); i != -1; \
3394 i = next_active_region_index_in_nid(i, nid))
3395
3396/**
3397 * free_bootmem_with_active_regions - Call free_bootmem_node for each active range
Randy Dunlap88ca3b92006-10-04 02:15:25 -07003398 * @nid: The node to free memory on. If MAX_NUMNODES, all nodes are freed.
3399 * @max_low_pfn: The highest PFN that will be passed to free_bootmem_node
Mel Gormanc7132162006-09-27 01:49:43 -07003400 *
3401 * If an architecture guarantees that all ranges registered with
3402 * add_active_ranges() contain no holes and may be freed, this
3403 * this function may be used instead of calling free_bootmem() manually.
3404 */
3405void __init free_bootmem_with_active_regions(int nid,
3406 unsigned long max_low_pfn)
3407{
3408 int i;
3409
3410 for_each_active_range_index_in_nid(i, nid) {
3411 unsigned long size_pages = 0;
3412 unsigned long end_pfn = early_node_map[i].end_pfn;
3413
3414 if (early_node_map[i].start_pfn >= max_low_pfn)
3415 continue;
3416
3417 if (end_pfn > max_low_pfn)
3418 end_pfn = max_low_pfn;
3419
3420 size_pages = end_pfn - early_node_map[i].start_pfn;
3421 free_bootmem_node(NODE_DATA(early_node_map[i].nid),
3422 PFN_PHYS(early_node_map[i].start_pfn),
3423 size_pages << PAGE_SHIFT);
3424 }
3425}
3426
Yinghai Lub5bc6c02008-06-14 18:32:52 -07003427void __init work_with_active_regions(int nid, work_fn_t work_fn, void *data)
3428{
3429 int i;
Yinghai Lud52d53b2008-06-16 20:10:55 -07003430 int ret;
Yinghai Lub5bc6c02008-06-14 18:32:52 -07003431
Yinghai Lud52d53b2008-06-16 20:10:55 -07003432 for_each_active_range_index_in_nid(i, nid) {
3433 ret = work_fn(early_node_map[i].start_pfn,
3434 early_node_map[i].end_pfn, data);
3435 if (ret)
3436 break;
3437 }
Yinghai Lub5bc6c02008-06-14 18:32:52 -07003438}
Mel Gormanc7132162006-09-27 01:49:43 -07003439/**
3440 * sparse_memory_present_with_active_regions - Call memory_present for each active range
Randy Dunlap88ca3b92006-10-04 02:15:25 -07003441 * @nid: The node to call memory_present for. If MAX_NUMNODES, all nodes will be used.
Mel Gormanc7132162006-09-27 01:49:43 -07003442 *
3443 * If an architecture guarantees that all ranges registered with
3444 * add_active_ranges() contain no holes and may be freed, this
Randy Dunlap88ca3b92006-10-04 02:15:25 -07003445 * function may be used instead of calling memory_present() manually.
Mel Gormanc7132162006-09-27 01:49:43 -07003446 */
3447void __init sparse_memory_present_with_active_regions(int nid)
3448{
3449 int i;
3450
3451 for_each_active_range_index_in_nid(i, nid)
3452 memory_present(early_node_map[i].nid,
3453 early_node_map[i].start_pfn,
3454 early_node_map[i].end_pfn);
3455}
3456
3457/**
3458 * get_pfn_range_for_nid - Return the start and end page frames for a node
Randy Dunlap88ca3b92006-10-04 02:15:25 -07003459 * @nid: The nid to return the range for. If MAX_NUMNODES, the min and max PFN are returned.
3460 * @start_pfn: Passed by reference. On return, it will have the node start_pfn.
3461 * @end_pfn: Passed by reference. On return, it will have the node end_pfn.
Mel Gormanc7132162006-09-27 01:49:43 -07003462 *
3463 * It returns the start and end page frame of a node based on information
3464 * provided by an arch calling add_active_range(). If called for a node
3465 * with no available memory, a warning is printed and the start and end
Randy Dunlap88ca3b92006-10-04 02:15:25 -07003466 * PFNs will be 0.
Mel Gormanc7132162006-09-27 01:49:43 -07003467 */
Yasunori Gotoa3142c82007-05-08 00:23:07 -07003468void __meminit get_pfn_range_for_nid(unsigned int nid,
Mel Gormanc7132162006-09-27 01:49:43 -07003469 unsigned long *start_pfn, unsigned long *end_pfn)
3470{
3471 int i;
3472 *start_pfn = -1UL;
3473 *end_pfn = 0;
3474
3475 for_each_active_range_index_in_nid(i, nid) {
3476 *start_pfn = min(*start_pfn, early_node_map[i].start_pfn);
3477 *end_pfn = max(*end_pfn, early_node_map[i].end_pfn);
3478 }
3479
Christoph Lameter633c0662007-10-16 01:25:37 -07003480 if (*start_pfn == -1UL)
Mel Gormanc7132162006-09-27 01:49:43 -07003481 *start_pfn = 0;
Mel Gormanc7132162006-09-27 01:49:43 -07003482}
3483
3484/*
Mel Gorman2a1e2742007-07-17 04:03:12 -07003485 * This finds a zone that can be used for ZONE_MOVABLE pages. The
3486 * assumption is made that zones within a node are ordered in monotonic
3487 * increasing memory addresses so that the "highest" populated zone is used
3488 */
Adrian Bunkb69a7282008-07-23 21:28:12 -07003489static void __init find_usable_zone_for_movable(void)
Mel Gorman2a1e2742007-07-17 04:03:12 -07003490{
3491 int zone_index;
3492 for (zone_index = MAX_NR_ZONES - 1; zone_index >= 0; zone_index--) {
3493 if (zone_index == ZONE_MOVABLE)
3494 continue;
3495
3496 if (arch_zone_highest_possible_pfn[zone_index] >
3497 arch_zone_lowest_possible_pfn[zone_index])
3498 break;
3499 }
3500
3501 VM_BUG_ON(zone_index == -1);
3502 movable_zone = zone_index;
3503}
3504
3505/*
3506 * The zone ranges provided by the architecture do not include ZONE_MOVABLE
3507 * because it is sized independant of architecture. Unlike the other zones,
3508 * the starting point for ZONE_MOVABLE is not fixed. It may be different
3509 * in each node depending on the size of each node and how evenly kernelcore
3510 * is distributed. This helper function adjusts the zone ranges
3511 * provided by the architecture for a given node by using the end of the
3512 * highest usable zone for ZONE_MOVABLE. This preserves the assumption that
3513 * zones within a node are in order of monotonic increases memory addresses
3514 */
Adrian Bunkb69a7282008-07-23 21:28:12 -07003515static void __meminit adjust_zone_range_for_zone_movable(int nid,
Mel Gorman2a1e2742007-07-17 04:03:12 -07003516 unsigned long zone_type,
3517 unsigned long node_start_pfn,
3518 unsigned long node_end_pfn,
3519 unsigned long *zone_start_pfn,
3520 unsigned long *zone_end_pfn)
3521{
3522 /* Only adjust if ZONE_MOVABLE is on this node */
3523 if (zone_movable_pfn[nid]) {
3524 /* Size ZONE_MOVABLE */
3525 if (zone_type == ZONE_MOVABLE) {
3526 *zone_start_pfn = zone_movable_pfn[nid];
3527 *zone_end_pfn = min(node_end_pfn,
3528 arch_zone_highest_possible_pfn[movable_zone]);
3529
3530 /* Adjust for ZONE_MOVABLE starting within this range */
3531 } else if (*zone_start_pfn < zone_movable_pfn[nid] &&
3532 *zone_end_pfn > zone_movable_pfn[nid]) {
3533 *zone_end_pfn = zone_movable_pfn[nid];
3534
3535 /* Check if this whole range is within ZONE_MOVABLE */
3536 } else if (*zone_start_pfn >= zone_movable_pfn[nid])
3537 *zone_start_pfn = *zone_end_pfn;
3538 }
3539}
3540
3541/*
Mel Gormanc7132162006-09-27 01:49:43 -07003542 * Return the number of pages a zone spans in a node, including holes
3543 * present_pages = zone_spanned_pages_in_node() - zone_absent_pages_in_node()
3544 */
Paul Mundt6ea6e682007-07-15 23:38:20 -07003545static unsigned long __meminit zone_spanned_pages_in_node(int nid,
Mel Gormanc7132162006-09-27 01:49:43 -07003546 unsigned long zone_type,
3547 unsigned long *ignored)
3548{
3549 unsigned long node_start_pfn, node_end_pfn;
3550 unsigned long zone_start_pfn, zone_end_pfn;
3551
3552 /* Get the start and end of the node and zone */
3553 get_pfn_range_for_nid(nid, &node_start_pfn, &node_end_pfn);
3554 zone_start_pfn = arch_zone_lowest_possible_pfn[zone_type];
3555 zone_end_pfn = arch_zone_highest_possible_pfn[zone_type];
Mel Gorman2a1e2742007-07-17 04:03:12 -07003556 adjust_zone_range_for_zone_movable(nid, zone_type,
3557 node_start_pfn, node_end_pfn,
3558 &zone_start_pfn, &zone_end_pfn);
Mel Gormanc7132162006-09-27 01:49:43 -07003559
3560 /* Check that this node has pages within the zone's required range */
3561 if (zone_end_pfn < node_start_pfn || zone_start_pfn > node_end_pfn)
3562 return 0;
3563
3564 /* Move the zone boundaries inside the node if necessary */
3565 zone_end_pfn = min(zone_end_pfn, node_end_pfn);
3566 zone_start_pfn = max(zone_start_pfn, node_start_pfn);
3567
3568 /* Return the spanned pages */
3569 return zone_end_pfn - zone_start_pfn;
3570}
3571
3572/*
3573 * Return the number of holes in a range on a node. If nid is MAX_NUMNODES,
Randy Dunlap88ca3b92006-10-04 02:15:25 -07003574 * then all holes in the requested range will be accounted for.
Mel Gormanc7132162006-09-27 01:49:43 -07003575 */
Adrian Bunkb69a7282008-07-23 21:28:12 -07003576static unsigned long __meminit __absent_pages_in_range(int nid,
Mel Gormanc7132162006-09-27 01:49:43 -07003577 unsigned long range_start_pfn,
3578 unsigned long range_end_pfn)
3579{
3580 int i = 0;
3581 unsigned long prev_end_pfn = 0, hole_pages = 0;
3582 unsigned long start_pfn;
3583
3584 /* Find the end_pfn of the first active range of pfns in the node */
3585 i = first_active_region_index_in_nid(nid);
3586 if (i == -1)
3587 return 0;
3588
Mel Gormanb5445f92007-07-26 10:41:18 -07003589 prev_end_pfn = min(early_node_map[i].start_pfn, range_end_pfn);
3590
Mel Gorman9c7cd682006-09-27 01:49:58 -07003591 /* Account for ranges before physical memory on this node */
3592 if (early_node_map[i].start_pfn > range_start_pfn)
Mel Gormanb5445f92007-07-26 10:41:18 -07003593 hole_pages = prev_end_pfn - range_start_pfn;
Mel Gormanc7132162006-09-27 01:49:43 -07003594
3595 /* Find all holes for the zone within the node */
3596 for (; i != -1; i = next_active_region_index_in_nid(i, nid)) {
3597
3598 /* No need to continue if prev_end_pfn is outside the zone */
3599 if (prev_end_pfn >= range_end_pfn)
3600 break;
3601
3602 /* Make sure the end of the zone is not within the hole */
3603 start_pfn = min(early_node_map[i].start_pfn, range_end_pfn);
3604 prev_end_pfn = max(prev_end_pfn, range_start_pfn);
3605
3606 /* Update the hole size cound and move on */
3607 if (start_pfn > range_start_pfn) {
3608 BUG_ON(prev_end_pfn > start_pfn);
3609 hole_pages += start_pfn - prev_end_pfn;
3610 }
3611 prev_end_pfn = early_node_map[i].end_pfn;
3612 }
3613
Mel Gorman9c7cd682006-09-27 01:49:58 -07003614 /* Account for ranges past physical memory on this node */
3615 if (range_end_pfn > prev_end_pfn)
Mel Gorman0c6cb972006-10-28 10:38:59 -07003616 hole_pages += range_end_pfn -
Mel Gorman9c7cd682006-09-27 01:49:58 -07003617 max(range_start_pfn, prev_end_pfn);
3618
Mel Gormanc7132162006-09-27 01:49:43 -07003619 return hole_pages;
3620}
3621
3622/**
3623 * absent_pages_in_range - Return number of page frames in holes within a range
3624 * @start_pfn: The start PFN to start searching for holes
3625 * @end_pfn: The end PFN to stop searching for holes
3626 *
Randy Dunlap88ca3b92006-10-04 02:15:25 -07003627 * It returns the number of pages frames in memory holes within a range.
Mel Gormanc7132162006-09-27 01:49:43 -07003628 */
3629unsigned long __init absent_pages_in_range(unsigned long start_pfn,
3630 unsigned long end_pfn)
3631{
3632 return __absent_pages_in_range(MAX_NUMNODES, start_pfn, end_pfn);
3633}
3634
3635/* Return the number of page frames in holes in a zone on a node */
Paul Mundt6ea6e682007-07-15 23:38:20 -07003636static unsigned long __meminit zone_absent_pages_in_node(int nid,
Mel Gormanc7132162006-09-27 01:49:43 -07003637 unsigned long zone_type,
3638 unsigned long *ignored)
3639{
Mel Gorman9c7cd682006-09-27 01:49:58 -07003640 unsigned long node_start_pfn, node_end_pfn;
3641 unsigned long zone_start_pfn, zone_end_pfn;
3642
3643 get_pfn_range_for_nid(nid, &node_start_pfn, &node_end_pfn);
3644 zone_start_pfn = max(arch_zone_lowest_possible_pfn[zone_type],
3645 node_start_pfn);
3646 zone_end_pfn = min(arch_zone_highest_possible_pfn[zone_type],
3647 node_end_pfn);
3648
Mel Gorman2a1e2742007-07-17 04:03:12 -07003649 adjust_zone_range_for_zone_movable(nid, zone_type,
3650 node_start_pfn, node_end_pfn,
3651 &zone_start_pfn, &zone_end_pfn);
Mel Gorman9c7cd682006-09-27 01:49:58 -07003652 return __absent_pages_in_range(nid, zone_start_pfn, zone_end_pfn);
Mel Gormanc7132162006-09-27 01:49:43 -07003653}
Mel Gorman0e0b8642006-09-27 01:49:56 -07003654
Mel Gormanc7132162006-09-27 01:49:43 -07003655#else
Paul Mundt6ea6e682007-07-15 23:38:20 -07003656static inline unsigned long __meminit zone_spanned_pages_in_node(int nid,
Mel Gormanc7132162006-09-27 01:49:43 -07003657 unsigned long zone_type,
3658 unsigned long *zones_size)
3659{
3660 return zones_size[zone_type];
3661}
3662
Paul Mundt6ea6e682007-07-15 23:38:20 -07003663static inline unsigned long __meminit zone_absent_pages_in_node(int nid,
Mel Gormanc7132162006-09-27 01:49:43 -07003664 unsigned long zone_type,
3665 unsigned long *zholes_size)
3666{
3667 if (!zholes_size)
3668 return 0;
3669
3670 return zholes_size[zone_type];
3671}
Mel Gorman0e0b8642006-09-27 01:49:56 -07003672
Mel Gormanc7132162006-09-27 01:49:43 -07003673#endif
3674
Yasunori Gotoa3142c82007-05-08 00:23:07 -07003675static void __meminit calculate_node_totalpages(struct pglist_data *pgdat,
Mel Gormanc7132162006-09-27 01:49:43 -07003676 unsigned long *zones_size, unsigned long *zholes_size)
3677{
3678 unsigned long realtotalpages, totalpages = 0;
3679 enum zone_type i;
3680
3681 for (i = 0; i < MAX_NR_ZONES; i++)
3682 totalpages += zone_spanned_pages_in_node(pgdat->node_id, i,
3683 zones_size);
3684 pgdat->node_spanned_pages = totalpages;
3685
3686 realtotalpages = totalpages;
3687 for (i = 0; i < MAX_NR_ZONES; i++)
3688 realtotalpages -=
3689 zone_absent_pages_in_node(pgdat->node_id, i,
3690 zholes_size);
3691 pgdat->node_present_pages = realtotalpages;
3692 printk(KERN_DEBUG "On node %d totalpages: %lu\n", pgdat->node_id,
3693 realtotalpages);
3694}
3695
Mel Gorman835c1342007-10-16 01:25:47 -07003696#ifndef CONFIG_SPARSEMEM
3697/*
3698 * Calculate the size of the zone->blockflags rounded to an unsigned long
Mel Gormand9c23402007-10-16 01:26:01 -07003699 * Start by making sure zonesize is a multiple of pageblock_order by rounding
3700 * up. Then use 1 NR_PAGEBLOCK_BITS worth of bits per pageblock, finally
Mel Gorman835c1342007-10-16 01:25:47 -07003701 * round what is now in bits to nearest long in bits, then return it in
3702 * bytes.
3703 */
3704static unsigned long __init usemap_size(unsigned long zonesize)
3705{
3706 unsigned long usemapsize;
3707
Mel Gormand9c23402007-10-16 01:26:01 -07003708 usemapsize = roundup(zonesize, pageblock_nr_pages);
3709 usemapsize = usemapsize >> pageblock_order;
Mel Gorman835c1342007-10-16 01:25:47 -07003710 usemapsize *= NR_PAGEBLOCK_BITS;
3711 usemapsize = roundup(usemapsize, 8 * sizeof(unsigned long));
3712
3713 return usemapsize / 8;
3714}
3715
3716static void __init setup_usemap(struct pglist_data *pgdat,
3717 struct zone *zone, unsigned long zonesize)
3718{
3719 unsigned long usemapsize = usemap_size(zonesize);
3720 zone->pageblock_flags = NULL;
Julia Lawall58a01a42009-01-06 14:39:28 -08003721 if (usemapsize)
Mel Gorman835c1342007-10-16 01:25:47 -07003722 zone->pageblock_flags = alloc_bootmem_node(pgdat, usemapsize);
Mel Gorman835c1342007-10-16 01:25:47 -07003723}
3724#else
3725static void inline setup_usemap(struct pglist_data *pgdat,
3726 struct zone *zone, unsigned long zonesize) {}
3727#endif /* CONFIG_SPARSEMEM */
3728
Mel Gormand9c23402007-10-16 01:26:01 -07003729#ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
Mel Gormanba72cb82007-11-28 16:21:13 -08003730
3731/* Return a sensible default order for the pageblock size. */
3732static inline int pageblock_default_order(void)
3733{
3734 if (HPAGE_SHIFT > PAGE_SHIFT)
3735 return HUGETLB_PAGE_ORDER;
3736
3737 return MAX_ORDER-1;
3738}
3739
Mel Gormand9c23402007-10-16 01:26:01 -07003740/* Initialise the number of pages represented by NR_PAGEBLOCK_BITS */
3741static inline void __init set_pageblock_order(unsigned int order)
3742{
3743 /* Check that pageblock_nr_pages has not already been setup */
3744 if (pageblock_order)
3745 return;
3746
3747 /*
3748 * Assume the largest contiguous order of interest is a huge page.
3749 * This value may be variable depending on boot parameters on IA64
3750 */
3751 pageblock_order = order;
3752}
3753#else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
3754
Mel Gormanba72cb82007-11-28 16:21:13 -08003755/*
3756 * When CONFIG_HUGETLB_PAGE_SIZE_VARIABLE is not set, set_pageblock_order()
3757 * and pageblock_default_order() are unused as pageblock_order is set
3758 * at compile-time. See include/linux/pageblock-flags.h for the values of
3759 * pageblock_order based on the kernel config
3760 */
3761static inline int pageblock_default_order(unsigned int order)
3762{
3763 return MAX_ORDER-1;
3764}
Mel Gormand9c23402007-10-16 01:26:01 -07003765#define set_pageblock_order(x) do {} while (0)
3766
3767#endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
3768
Linus Torvalds1da177e2005-04-16 15:20:36 -07003769/*
3770 * Set up the zone data structures:
3771 * - mark all pages reserved
3772 * - mark all memory queues empty
3773 * - clear the memory bitmaps
3774 */
Alexander van Heukelumb5a0e012008-02-23 15:24:06 -08003775static void __paginginit free_area_init_core(struct pglist_data *pgdat,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003776 unsigned long *zones_size, unsigned long *zholes_size)
3777{
Christoph Lameter2f1b6242006-09-25 23:31:13 -07003778 enum zone_type j;
Dave Hansened8ece22005-10-29 18:16:50 -07003779 int nid = pgdat->node_id;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003780 unsigned long zone_start_pfn = pgdat->node_start_pfn;
Yasunori Goto718127c2006-06-23 02:03:10 -07003781 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003782
Dave Hansen208d54e2005-10-29 18:16:52 -07003783 pgdat_resize_init(pgdat);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003784 pgdat->nr_zones = 0;
3785 init_waitqueue_head(&pgdat->kswapd_wait);
3786 pgdat->kswapd_max_order = 0;
KAMEZAWA Hiroyuki52d4b9a2008-10-18 20:28:16 -07003787 pgdat_page_cgroup_init(pgdat);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003788
3789 for (j = 0; j < MAX_NR_ZONES; j++) {
3790 struct zone *zone = pgdat->node_zones + j;
Mel Gorman0e0b8642006-09-27 01:49:56 -07003791 unsigned long size, realsize, memmap_pages;
Christoph Lameterb69408e2008-10-18 20:26:14 -07003792 enum lru_list l;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003793
Mel Gormanc7132162006-09-27 01:49:43 -07003794 size = zone_spanned_pages_in_node(nid, j, zones_size);
3795 realsize = size - zone_absent_pages_in_node(nid, j,
3796 zholes_size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003797
Mel Gorman0e0b8642006-09-27 01:49:56 -07003798 /*
3799 * Adjust realsize so that it accounts for how much memory
3800 * is used by this zone for memmap. This affects the watermark
3801 * and per-cpu initialisations
3802 */
Johannes Weinerf7232152008-05-23 13:04:21 -07003803 memmap_pages =
3804 PAGE_ALIGN(size * sizeof(struct page)) >> PAGE_SHIFT;
Mel Gorman0e0b8642006-09-27 01:49:56 -07003805 if (realsize >= memmap_pages) {
3806 realsize -= memmap_pages;
Yinghai Lu5594c8c2009-01-06 14:39:14 -08003807 if (memmap_pages)
3808 printk(KERN_DEBUG
3809 " %s zone: %lu pages used for memmap\n",
3810 zone_names[j], memmap_pages);
Mel Gorman0e0b8642006-09-27 01:49:56 -07003811 } else
3812 printk(KERN_WARNING
3813 " %s zone: %lu pages exceeds realsize %lu\n",
3814 zone_names[j], memmap_pages, realsize);
3815
Christoph Lameter62672762007-02-10 01:43:07 -08003816 /* Account for reserved pages */
3817 if (j == 0 && realsize > dma_reserve) {
Mel Gorman0e0b8642006-09-27 01:49:56 -07003818 realsize -= dma_reserve;
Yinghai Lud903ef92008-10-18 20:27:06 -07003819 printk(KERN_DEBUG " %s zone: %lu pages reserved\n",
Christoph Lameter62672762007-02-10 01:43:07 -08003820 zone_names[0], dma_reserve);
Mel Gorman0e0b8642006-09-27 01:49:56 -07003821 }
3822
Christoph Lameter98d2b0e2006-09-25 23:31:12 -07003823 if (!is_highmem_idx(j))
Linus Torvalds1da177e2005-04-16 15:20:36 -07003824 nr_kernel_pages += realsize;
3825 nr_all_pages += realsize;
3826
3827 zone->spanned_pages = size;
3828 zone->present_pages = realsize;
Christoph Lameter96146342006-07-03 00:24:13 -07003829#ifdef CONFIG_NUMA
Christoph Lameterd5f541e2006-09-27 01:50:08 -07003830 zone->node = nid;
Christoph Lameter8417bba2006-09-25 23:31:51 -07003831 zone->min_unmapped_pages = (realsize*sysctl_min_unmapped_ratio)
Christoph Lameter96146342006-07-03 00:24:13 -07003832 / 100;
Christoph Lameter0ff38492006-09-25 23:31:52 -07003833 zone->min_slab_pages = (realsize * sysctl_min_slab_ratio) / 100;
Christoph Lameter96146342006-07-03 00:24:13 -07003834#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07003835 zone->name = zone_names[j];
3836 spin_lock_init(&zone->lock);
3837 spin_lock_init(&zone->lru_lock);
Dave Hansenbdc8cb92005-10-29 18:16:53 -07003838 zone_seqlock_init(zone);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003839 zone->zone_pgdat = pgdat;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003840
Martin Bligh3bb1a852006-10-28 10:38:24 -07003841 zone->prev_priority = DEF_PRIORITY;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003842
Dave Hansened8ece22005-10-29 18:16:50 -07003843 zone_pcp_init(zone);
Christoph Lameterb69408e2008-10-18 20:26:14 -07003844 for_each_lru(l) {
3845 INIT_LIST_HEAD(&zone->lru[l].list);
Wu Fengguangf8629632009-09-21 17:03:11 -07003846 zone->reclaim_stat.nr_saved_scan[l] = 0;
Christoph Lameterb69408e2008-10-18 20:26:14 -07003847 }
KOSAKI Motohiro6e901572009-01-07 18:08:15 -08003848 zone->reclaim_stat.recent_rotated[0] = 0;
3849 zone->reclaim_stat.recent_rotated[1] = 0;
3850 zone->reclaim_stat.recent_scanned[0] = 0;
3851 zone->reclaim_stat.recent_scanned[1] = 0;
Christoph Lameter2244b952006-06-30 01:55:33 -07003852 zap_zone_vm_stats(zone);
David Rientjese815af92007-10-16 23:25:54 -07003853 zone->flags = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003854 if (!size)
3855 continue;
3856
Mel Gormanba72cb82007-11-28 16:21:13 -08003857 set_pageblock_order(pageblock_default_order());
Mel Gorman835c1342007-10-16 01:25:47 -07003858 setup_usemap(pgdat, zone, size);
Dave Hansena2f3aa02007-01-10 23:15:30 -08003859 ret = init_currently_empty_zone(zone, zone_start_pfn,
3860 size, MEMMAP_EARLY);
Yasunori Goto718127c2006-06-23 02:03:10 -07003861 BUG_ON(ret);
Heiko Carstens76cdd582008-05-14 16:05:52 -07003862 memmap_init(size, nid, j, zone_start_pfn);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003863 zone_start_pfn += size;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003864 }
3865}
3866
Sam Ravnborg577a32f2007-05-17 23:29:25 +02003867static void __init_refok alloc_node_mem_map(struct pglist_data *pgdat)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003868{
Linus Torvalds1da177e2005-04-16 15:20:36 -07003869 /* Skip empty nodes */
3870 if (!pgdat->node_spanned_pages)
3871 return;
3872
Andy Whitcroftd41dee32005-06-23 00:07:54 -07003873#ifdef CONFIG_FLAT_NODE_MEM_MAP
Linus Torvalds1da177e2005-04-16 15:20:36 -07003874 /* ia64 gets its own node_mem_map, before this, without bootmem */
3875 if (!pgdat->node_mem_map) {
Bob Piccoe984bb42006-05-20 15:00:31 -07003876 unsigned long size, start, end;
Andy Whitcroftd41dee32005-06-23 00:07:54 -07003877 struct page *map;
3878
Bob Piccoe984bb42006-05-20 15:00:31 -07003879 /*
3880 * The zone's endpoints aren't required to be MAX_ORDER
3881 * aligned but the node_mem_map endpoints must be in order
3882 * for the buddy allocator to function correctly.
3883 */
3884 start = pgdat->node_start_pfn & ~(MAX_ORDER_NR_PAGES - 1);
3885 end = pgdat->node_start_pfn + pgdat->node_spanned_pages;
3886 end = ALIGN(end, MAX_ORDER_NR_PAGES);
3887 size = (end - start) * sizeof(struct page);
Dave Hansen6f167ec2005-06-23 00:07:39 -07003888 map = alloc_remap(pgdat->node_id, size);
3889 if (!map)
3890 map = alloc_bootmem_node(pgdat, size);
Bob Piccoe984bb42006-05-20 15:00:31 -07003891 pgdat->node_mem_map = map + (pgdat->node_start_pfn - start);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003892 }
Roman Zippel12d810c2007-05-31 00:40:54 -07003893#ifndef CONFIG_NEED_MULTIPLE_NODES
Linus Torvalds1da177e2005-04-16 15:20:36 -07003894 /*
3895 * With no DISCONTIG, the global mem_map is just set as node 0's
3896 */
Mel Gormanc7132162006-09-27 01:49:43 -07003897 if (pgdat == NODE_DATA(0)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07003898 mem_map = NODE_DATA(0)->node_mem_map;
Mel Gormanc7132162006-09-27 01:49:43 -07003899#ifdef CONFIG_ARCH_POPULATES_NODE_MAP
3900 if (page_to_pfn(mem_map) != pgdat->node_start_pfn)
Thomas Bogendoerfer467bc462008-01-08 15:33:11 -08003901 mem_map -= (pgdat->node_start_pfn - ARCH_PFN_OFFSET);
Mel Gormanc7132162006-09-27 01:49:43 -07003902#endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
3903 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07003904#endif
Andy Whitcroftd41dee32005-06-23 00:07:54 -07003905#endif /* CONFIG_FLAT_NODE_MEM_MAP */
Linus Torvalds1da177e2005-04-16 15:20:36 -07003906}
3907
Johannes Weiner9109fb72008-07-23 21:27:20 -07003908void __paginginit free_area_init_node(int nid, unsigned long *zones_size,
3909 unsigned long node_start_pfn, unsigned long *zholes_size)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003910{
Johannes Weiner9109fb72008-07-23 21:27:20 -07003911 pg_data_t *pgdat = NODE_DATA(nid);
3912
Linus Torvalds1da177e2005-04-16 15:20:36 -07003913 pgdat->node_id = nid;
3914 pgdat->node_start_pfn = node_start_pfn;
Mel Gormanc7132162006-09-27 01:49:43 -07003915 calculate_node_totalpages(pgdat, zones_size, zholes_size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003916
3917 alloc_node_mem_map(pgdat);
Yinghai Lue8c27ac2008-06-01 13:15:22 -07003918#ifdef CONFIG_FLAT_NODE_MEM_MAP
3919 printk(KERN_DEBUG "free_area_init_node: node %d, pgdat %08lx, node_mem_map %08lx\n",
3920 nid, (unsigned long)pgdat,
3921 (unsigned long)pgdat->node_mem_map);
3922#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07003923
3924 free_area_init_core(pgdat, zones_size, zholes_size);
3925}
3926
Mel Gormanc7132162006-09-27 01:49:43 -07003927#ifdef CONFIG_ARCH_POPULATES_NODE_MAP
Miklos Szeredi418508c2007-05-23 13:57:55 -07003928
3929#if MAX_NUMNODES > 1
3930/*
3931 * Figure out the number of possible node ids.
3932 */
3933static void __init setup_nr_node_ids(void)
3934{
3935 unsigned int node;
3936 unsigned int highest = 0;
3937
3938 for_each_node_mask(node, node_possible_map)
3939 highest = node;
3940 nr_node_ids = highest + 1;
3941}
3942#else
3943static inline void setup_nr_node_ids(void)
3944{
3945}
3946#endif
3947
Mel Gormanc7132162006-09-27 01:49:43 -07003948/**
3949 * add_active_range - Register a range of PFNs backed by physical memory
3950 * @nid: The node ID the range resides on
3951 * @start_pfn: The start PFN of the available physical memory
3952 * @end_pfn: The end PFN of the available physical memory
3953 *
3954 * These ranges are stored in an early_node_map[] and later used by
3955 * free_area_init_nodes() to calculate zone sizes and holes. If the
3956 * range spans a memory hole, it is up to the architecture to ensure
3957 * the memory is not freed by the bootmem allocator. If possible
3958 * the range being registered will be merged with existing ranges.
3959 */
3960void __init add_active_range(unsigned int nid, unsigned long start_pfn,
3961 unsigned long end_pfn)
3962{
3963 int i;
3964
Mel Gorman6b74ab92008-07-23 21:26:49 -07003965 mminit_dprintk(MMINIT_TRACE, "memory_register",
3966 "Entering add_active_range(%d, %#lx, %#lx) "
3967 "%d entries of %d used\n",
3968 nid, start_pfn, end_pfn,
3969 nr_nodemap_entries, MAX_ACTIVE_REGIONS);
Mel Gormanc7132162006-09-27 01:49:43 -07003970
Mel Gorman2dbb51c2008-07-23 21:26:52 -07003971 mminit_validate_memmodel_limits(&start_pfn, &end_pfn);
3972
Mel Gormanc7132162006-09-27 01:49:43 -07003973 /* Merge with existing active regions if possible */
3974 for (i = 0; i < nr_nodemap_entries; i++) {
3975 if (early_node_map[i].nid != nid)
3976 continue;
3977
3978 /* Skip if an existing region covers this new one */
3979 if (start_pfn >= early_node_map[i].start_pfn &&
3980 end_pfn <= early_node_map[i].end_pfn)
3981 return;
3982
3983 /* Merge forward if suitable */
3984 if (start_pfn <= early_node_map[i].end_pfn &&
3985 end_pfn > early_node_map[i].end_pfn) {
3986 early_node_map[i].end_pfn = end_pfn;
3987 return;
3988 }
3989
3990 /* Merge backward if suitable */
3991 if (start_pfn < early_node_map[i].end_pfn &&
3992 end_pfn >= early_node_map[i].start_pfn) {
3993 early_node_map[i].start_pfn = start_pfn;
3994 return;
3995 }
3996 }
3997
3998 /* Check that early_node_map is large enough */
3999 if (i >= MAX_ACTIVE_REGIONS) {
4000 printk(KERN_CRIT "More than %d memory regions, truncating\n",
4001 MAX_ACTIVE_REGIONS);
4002 return;
4003 }
4004
4005 early_node_map[i].nid = nid;
4006 early_node_map[i].start_pfn = start_pfn;
4007 early_node_map[i].end_pfn = end_pfn;
4008 nr_nodemap_entries = i + 1;
4009}
4010
4011/**
Yinghai Lucc1050b2008-06-13 19:08:52 -07004012 * remove_active_range - Shrink an existing registered range of PFNs
Mel Gormanc7132162006-09-27 01:49:43 -07004013 * @nid: The node id the range is on that should be shrunk
Yinghai Lucc1050b2008-06-13 19:08:52 -07004014 * @start_pfn: The new PFN of the range
4015 * @end_pfn: The new PFN of the range
Mel Gormanc7132162006-09-27 01:49:43 -07004016 *
4017 * i386 with NUMA use alloc_remap() to store a node_mem_map on a local node.
Yinghai Lucc1a9d82008-06-08 19:39:16 -07004018 * The map is kept near the end physical page range that has already been
4019 * registered. This function allows an arch to shrink an existing registered
4020 * range.
Mel Gormanc7132162006-09-27 01:49:43 -07004021 */
Yinghai Lucc1050b2008-06-13 19:08:52 -07004022void __init remove_active_range(unsigned int nid, unsigned long start_pfn,
4023 unsigned long end_pfn)
Mel Gormanc7132162006-09-27 01:49:43 -07004024{
Yinghai Lucc1a9d82008-06-08 19:39:16 -07004025 int i, j;
4026 int removed = 0;
Mel Gormanc7132162006-09-27 01:49:43 -07004027
Yinghai Lucc1050b2008-06-13 19:08:52 -07004028 printk(KERN_DEBUG "remove_active_range (%d, %lu, %lu)\n",
4029 nid, start_pfn, end_pfn);
4030
Mel Gormanc7132162006-09-27 01:49:43 -07004031 /* Find the old active region end and shrink */
Yinghai Lucc1a9d82008-06-08 19:39:16 -07004032 for_each_active_range_index_in_nid(i, nid) {
Yinghai Lucc1050b2008-06-13 19:08:52 -07004033 if (early_node_map[i].start_pfn >= start_pfn &&
4034 early_node_map[i].end_pfn <= end_pfn) {
Yinghai Lucc1a9d82008-06-08 19:39:16 -07004035 /* clear it */
Yinghai Lucc1050b2008-06-13 19:08:52 -07004036 early_node_map[i].start_pfn = 0;
Yinghai Lucc1a9d82008-06-08 19:39:16 -07004037 early_node_map[i].end_pfn = 0;
4038 removed = 1;
4039 continue;
Mel Gormanc7132162006-09-27 01:49:43 -07004040 }
Yinghai Lucc1050b2008-06-13 19:08:52 -07004041 if (early_node_map[i].start_pfn < start_pfn &&
4042 early_node_map[i].end_pfn > start_pfn) {
4043 unsigned long temp_end_pfn = early_node_map[i].end_pfn;
4044 early_node_map[i].end_pfn = start_pfn;
4045 if (temp_end_pfn > end_pfn)
4046 add_active_range(nid, end_pfn, temp_end_pfn);
4047 continue;
4048 }
4049 if (early_node_map[i].start_pfn >= start_pfn &&
4050 early_node_map[i].end_pfn > end_pfn &&
4051 early_node_map[i].start_pfn < end_pfn) {
4052 early_node_map[i].start_pfn = end_pfn;
Yinghai Lucc1a9d82008-06-08 19:39:16 -07004053 continue;
4054 }
4055 }
4056
4057 if (!removed)
4058 return;
4059
4060 /* remove the blank ones */
4061 for (i = nr_nodemap_entries - 1; i > 0; i--) {
4062 if (early_node_map[i].nid != nid)
4063 continue;
4064 if (early_node_map[i].end_pfn)
4065 continue;
4066 /* we found it, get rid of it */
4067 for (j = i; j < nr_nodemap_entries - 1; j++)
4068 memcpy(&early_node_map[j], &early_node_map[j+1],
4069 sizeof(early_node_map[j]));
4070 j = nr_nodemap_entries - 1;
4071 memset(&early_node_map[j], 0, sizeof(early_node_map[j]));
4072 nr_nodemap_entries--;
4073 }
Mel Gormanc7132162006-09-27 01:49:43 -07004074}
4075
4076/**
4077 * remove_all_active_ranges - Remove all currently registered regions
Randy Dunlap88ca3b92006-10-04 02:15:25 -07004078 *
Mel Gormanc7132162006-09-27 01:49:43 -07004079 * During discovery, it may be found that a table like SRAT is invalid
4080 * and an alternative discovery method must be used. This function removes
4081 * all currently registered regions.
4082 */
Randy Dunlap88ca3b92006-10-04 02:15:25 -07004083void __init remove_all_active_ranges(void)
Mel Gormanc7132162006-09-27 01:49:43 -07004084{
4085 memset(early_node_map, 0, sizeof(early_node_map));
4086 nr_nodemap_entries = 0;
4087}
4088
4089/* Compare two active node_active_regions */
4090static int __init cmp_node_active_region(const void *a, const void *b)
4091{
4092 struct node_active_region *arange = (struct node_active_region *)a;
4093 struct node_active_region *brange = (struct node_active_region *)b;
4094
4095 /* Done this way to avoid overflows */
4096 if (arange->start_pfn > brange->start_pfn)
4097 return 1;
4098 if (arange->start_pfn < brange->start_pfn)
4099 return -1;
4100
4101 return 0;
4102}
4103
4104/* sort the node_map by start_pfn */
4105static void __init sort_node_map(void)
4106{
4107 sort(early_node_map, (size_t)nr_nodemap_entries,
4108 sizeof(struct node_active_region),
4109 cmp_node_active_region, NULL);
4110}
4111
Mel Gormana6af2bc2007-02-10 01:42:57 -08004112/* Find the lowest pfn for a node */
Adrian Bunkb69a7282008-07-23 21:28:12 -07004113static unsigned long __init find_min_pfn_for_node(int nid)
Mel Gormanc7132162006-09-27 01:49:43 -07004114{
4115 int i;
Mel Gormana6af2bc2007-02-10 01:42:57 -08004116 unsigned long min_pfn = ULONG_MAX;
Mel Gorman1abbfb42006-11-23 12:01:41 +00004117
Mel Gormanc7132162006-09-27 01:49:43 -07004118 /* Assuming a sorted map, the first range found has the starting pfn */
4119 for_each_active_range_index_in_nid(i, nid)
Mel Gormana6af2bc2007-02-10 01:42:57 -08004120 min_pfn = min(min_pfn, early_node_map[i].start_pfn);
Mel Gormanc7132162006-09-27 01:49:43 -07004121
Mel Gormana6af2bc2007-02-10 01:42:57 -08004122 if (min_pfn == ULONG_MAX) {
4123 printk(KERN_WARNING
Paul Jackson2bc0d262008-06-22 07:22:17 -07004124 "Could not find start_pfn for node %d\n", nid);
Mel Gormana6af2bc2007-02-10 01:42:57 -08004125 return 0;
4126 }
4127
4128 return min_pfn;
Mel Gormanc7132162006-09-27 01:49:43 -07004129}
4130
4131/**
4132 * find_min_pfn_with_active_regions - Find the minimum PFN registered
4133 *
4134 * It returns the minimum PFN based on information provided via
Randy Dunlap88ca3b92006-10-04 02:15:25 -07004135 * add_active_range().
Mel Gormanc7132162006-09-27 01:49:43 -07004136 */
4137unsigned long __init find_min_pfn_with_active_regions(void)
4138{
4139 return find_min_pfn_for_node(MAX_NUMNODES);
4140}
4141
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07004142/*
4143 * early_calculate_totalpages()
4144 * Sum pages in active regions for movable zone.
4145 * Populate N_HIGH_MEMORY for calculating usable_nodes.
4146 */
Adrian Bunk484f51f2007-10-16 01:26:03 -07004147static unsigned long __init early_calculate_totalpages(void)
Mel Gorman7e63efe2007-07-17 04:03:15 -07004148{
4149 int i;
4150 unsigned long totalpages = 0;
4151
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07004152 for (i = 0; i < nr_nodemap_entries; i++) {
4153 unsigned long pages = early_node_map[i].end_pfn -
Mel Gorman7e63efe2007-07-17 04:03:15 -07004154 early_node_map[i].start_pfn;
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07004155 totalpages += pages;
4156 if (pages)
4157 node_set_state(early_node_map[i].nid, N_HIGH_MEMORY);
4158 }
4159 return totalpages;
Mel Gorman7e63efe2007-07-17 04:03:15 -07004160}
4161
Mel Gorman2a1e2742007-07-17 04:03:12 -07004162/*
4163 * Find the PFN the Movable zone begins in each node. Kernel memory
4164 * is spread evenly between nodes as long as the nodes have enough
4165 * memory. When they don't, some nodes will have more kernelcore than
4166 * others
4167 */
Adrian Bunkb69a7282008-07-23 21:28:12 -07004168static void __init find_zone_movable_pfns_for_nodes(unsigned long *movable_pfn)
Mel Gorman2a1e2742007-07-17 04:03:12 -07004169{
4170 int i, nid;
4171 unsigned long usable_startpfn;
4172 unsigned long kernelcore_node, kernelcore_remaining;
Yinghai Lu66918dc2009-06-30 11:41:37 -07004173 /* save the state before borrow the nodemask */
4174 nodemask_t saved_node_state = node_states[N_HIGH_MEMORY];
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07004175 unsigned long totalpages = early_calculate_totalpages();
4176 int usable_nodes = nodes_weight(node_states[N_HIGH_MEMORY]);
Mel Gorman2a1e2742007-07-17 04:03:12 -07004177
Mel Gorman7e63efe2007-07-17 04:03:15 -07004178 /*
4179 * If movablecore was specified, calculate what size of
4180 * kernelcore that corresponds so that memory usable for
4181 * any allocation type is evenly spread. If both kernelcore
4182 * and movablecore are specified, then the value of kernelcore
4183 * will be used for required_kernelcore if it's greater than
4184 * what movablecore would have allowed.
4185 */
4186 if (required_movablecore) {
Mel Gorman7e63efe2007-07-17 04:03:15 -07004187 unsigned long corepages;
4188
4189 /*
4190 * Round-up so that ZONE_MOVABLE is at least as large as what
4191 * was requested by the user
4192 */
4193 required_movablecore =
4194 roundup(required_movablecore, MAX_ORDER_NR_PAGES);
4195 corepages = totalpages - required_movablecore;
4196
4197 required_kernelcore = max(required_kernelcore, corepages);
4198 }
4199
Mel Gorman2a1e2742007-07-17 04:03:12 -07004200 /* If kernelcore was not specified, there is no ZONE_MOVABLE */
4201 if (!required_kernelcore)
Yinghai Lu66918dc2009-06-30 11:41:37 -07004202 goto out;
Mel Gorman2a1e2742007-07-17 04:03:12 -07004203
4204 /* usable_startpfn is the lowest possible pfn ZONE_MOVABLE can be at */
4205 find_usable_zone_for_movable();
4206 usable_startpfn = arch_zone_lowest_possible_pfn[movable_zone];
4207
4208restart:
4209 /* Spread kernelcore memory as evenly as possible throughout nodes */
4210 kernelcore_node = required_kernelcore / usable_nodes;
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07004211 for_each_node_state(nid, N_HIGH_MEMORY) {
Mel Gorman2a1e2742007-07-17 04:03:12 -07004212 /*
4213 * Recalculate kernelcore_node if the division per node
4214 * now exceeds what is necessary to satisfy the requested
4215 * amount of memory for the kernel
4216 */
4217 if (required_kernelcore < kernelcore_node)
4218 kernelcore_node = required_kernelcore / usable_nodes;
4219
4220 /*
4221 * As the map is walked, we track how much memory is usable
4222 * by the kernel using kernelcore_remaining. When it is
4223 * 0, the rest of the node is usable by ZONE_MOVABLE
4224 */
4225 kernelcore_remaining = kernelcore_node;
4226
4227 /* Go through each range of PFNs within this node */
4228 for_each_active_range_index_in_nid(i, nid) {
4229 unsigned long start_pfn, end_pfn;
4230 unsigned long size_pages;
4231
4232 start_pfn = max(early_node_map[i].start_pfn,
4233 zone_movable_pfn[nid]);
4234 end_pfn = early_node_map[i].end_pfn;
4235 if (start_pfn >= end_pfn)
4236 continue;
4237
4238 /* Account for what is only usable for kernelcore */
4239 if (start_pfn < usable_startpfn) {
4240 unsigned long kernel_pages;
4241 kernel_pages = min(end_pfn, usable_startpfn)
4242 - start_pfn;
4243
4244 kernelcore_remaining -= min(kernel_pages,
4245 kernelcore_remaining);
4246 required_kernelcore -= min(kernel_pages,
4247 required_kernelcore);
4248
4249 /* Continue if range is now fully accounted */
4250 if (end_pfn <= usable_startpfn) {
4251
4252 /*
4253 * Push zone_movable_pfn to the end so
4254 * that if we have to rebalance
4255 * kernelcore across nodes, we will
4256 * not double account here
4257 */
4258 zone_movable_pfn[nid] = end_pfn;
4259 continue;
4260 }
4261 start_pfn = usable_startpfn;
4262 }
4263
4264 /*
4265 * The usable PFN range for ZONE_MOVABLE is from
4266 * start_pfn->end_pfn. Calculate size_pages as the
4267 * number of pages used as kernelcore
4268 */
4269 size_pages = end_pfn - start_pfn;
4270 if (size_pages > kernelcore_remaining)
4271 size_pages = kernelcore_remaining;
4272 zone_movable_pfn[nid] = start_pfn + size_pages;
4273
4274 /*
4275 * Some kernelcore has been met, update counts and
4276 * break if the kernelcore for this node has been
4277 * satisified
4278 */
4279 required_kernelcore -= min(required_kernelcore,
4280 size_pages);
4281 kernelcore_remaining -= size_pages;
4282 if (!kernelcore_remaining)
4283 break;
4284 }
4285 }
4286
4287 /*
4288 * If there is still required_kernelcore, we do another pass with one
4289 * less node in the count. This will push zone_movable_pfn[nid] further
4290 * along on the nodes that still have memory until kernelcore is
4291 * satisified
4292 */
4293 usable_nodes--;
4294 if (usable_nodes && required_kernelcore > usable_nodes)
4295 goto restart;
4296
4297 /* Align start of ZONE_MOVABLE on all nids to MAX_ORDER_NR_PAGES */
4298 for (nid = 0; nid < MAX_NUMNODES; nid++)
4299 zone_movable_pfn[nid] =
4300 roundup(zone_movable_pfn[nid], MAX_ORDER_NR_PAGES);
Yinghai Lu66918dc2009-06-30 11:41:37 -07004301
4302out:
4303 /* restore the node_state */
4304 node_states[N_HIGH_MEMORY] = saved_node_state;
Mel Gorman2a1e2742007-07-17 04:03:12 -07004305}
4306
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07004307/* Any regular memory on that node ? */
4308static void check_for_regular_memory(pg_data_t *pgdat)
4309{
4310#ifdef CONFIG_HIGHMEM
4311 enum zone_type zone_type;
4312
4313 for (zone_type = 0; zone_type <= ZONE_NORMAL; zone_type++) {
4314 struct zone *zone = &pgdat->node_zones[zone_type];
4315 if (zone->present_pages)
4316 node_set_state(zone_to_nid(zone), N_NORMAL_MEMORY);
4317 }
4318#endif
4319}
4320
Mel Gormanc7132162006-09-27 01:49:43 -07004321/**
4322 * free_area_init_nodes - Initialise all pg_data_t and zone data
Randy Dunlap88ca3b92006-10-04 02:15:25 -07004323 * @max_zone_pfn: an array of max PFNs for each zone
Mel Gormanc7132162006-09-27 01:49:43 -07004324 *
4325 * This will call free_area_init_node() for each active node in the system.
4326 * Using the page ranges provided by add_active_range(), the size of each
4327 * zone in each node and their holes is calculated. If the maximum PFN
4328 * between two adjacent zones match, it is assumed that the zone is empty.
4329 * For example, if arch_max_dma_pfn == arch_max_dma32_pfn, it is assumed
4330 * that arch_max_dma32_pfn has no pages. It is also assumed that a zone
4331 * starts where the previous one ended. For example, ZONE_DMA32 starts
4332 * at arch_max_dma_pfn.
4333 */
4334void __init free_area_init_nodes(unsigned long *max_zone_pfn)
4335{
4336 unsigned long nid;
Andrew Mortondb991002008-10-15 22:01:07 -07004337 int i;
Mel Gormanc7132162006-09-27 01:49:43 -07004338
Mel Gormana6af2bc2007-02-10 01:42:57 -08004339 /* Sort early_node_map as initialisation assumes it is sorted */
4340 sort_node_map();
4341
Mel Gormanc7132162006-09-27 01:49:43 -07004342 /* Record where the zone boundaries are */
4343 memset(arch_zone_lowest_possible_pfn, 0,
4344 sizeof(arch_zone_lowest_possible_pfn));
4345 memset(arch_zone_highest_possible_pfn, 0,
4346 sizeof(arch_zone_highest_possible_pfn));
4347 arch_zone_lowest_possible_pfn[0] = find_min_pfn_with_active_regions();
4348 arch_zone_highest_possible_pfn[0] = max_zone_pfn[0];
4349 for (i = 1; i < MAX_NR_ZONES; i++) {
Mel Gorman2a1e2742007-07-17 04:03:12 -07004350 if (i == ZONE_MOVABLE)
4351 continue;
Mel Gormanc7132162006-09-27 01:49:43 -07004352 arch_zone_lowest_possible_pfn[i] =
4353 arch_zone_highest_possible_pfn[i-1];
4354 arch_zone_highest_possible_pfn[i] =
4355 max(max_zone_pfn[i], arch_zone_lowest_possible_pfn[i]);
4356 }
Mel Gorman2a1e2742007-07-17 04:03:12 -07004357 arch_zone_lowest_possible_pfn[ZONE_MOVABLE] = 0;
4358 arch_zone_highest_possible_pfn[ZONE_MOVABLE] = 0;
4359
4360 /* Find the PFNs that ZONE_MOVABLE begins at in each node */
4361 memset(zone_movable_pfn, 0, sizeof(zone_movable_pfn));
4362 find_zone_movable_pfns_for_nodes(zone_movable_pfn);
Mel Gormanc7132162006-09-27 01:49:43 -07004363
Mel Gormanc7132162006-09-27 01:49:43 -07004364 /* Print out the zone ranges */
4365 printk("Zone PFN ranges:\n");
Mel Gorman2a1e2742007-07-17 04:03:12 -07004366 for (i = 0; i < MAX_NR_ZONES; i++) {
4367 if (i == ZONE_MOVABLE)
4368 continue;
Paul Jackson5dab8ec2008-06-25 05:44:40 -07004369 printk(" %-8s %0#10lx -> %0#10lx\n",
Mel Gormanc7132162006-09-27 01:49:43 -07004370 zone_names[i],
4371 arch_zone_lowest_possible_pfn[i],
4372 arch_zone_highest_possible_pfn[i]);
Mel Gorman2a1e2742007-07-17 04:03:12 -07004373 }
4374
4375 /* Print out the PFNs ZONE_MOVABLE begins at in each node */
4376 printk("Movable zone start PFN for each node\n");
4377 for (i = 0; i < MAX_NUMNODES; i++) {
4378 if (zone_movable_pfn[i])
4379 printk(" Node %d: %lu\n", i, zone_movable_pfn[i]);
4380 }
Mel Gormanc7132162006-09-27 01:49:43 -07004381
4382 /* Print out the early_node_map[] */
4383 printk("early_node_map[%d] active PFN ranges\n", nr_nodemap_entries);
4384 for (i = 0; i < nr_nodemap_entries; i++)
Paul Jackson5dab8ec2008-06-25 05:44:40 -07004385 printk(" %3d: %0#10lx -> %0#10lx\n", early_node_map[i].nid,
Mel Gormanc7132162006-09-27 01:49:43 -07004386 early_node_map[i].start_pfn,
4387 early_node_map[i].end_pfn);
4388
4389 /* Initialise every node */
Mel Gorman708614e2008-07-23 21:26:51 -07004390 mminit_verify_pageflags_layout();
Christoph Lameter8ef82862007-02-20 13:57:52 -08004391 setup_nr_node_ids();
Mel Gormanc7132162006-09-27 01:49:43 -07004392 for_each_online_node(nid) {
4393 pg_data_t *pgdat = NODE_DATA(nid);
Johannes Weiner9109fb72008-07-23 21:27:20 -07004394 free_area_init_node(nid, NULL,
Mel Gormanc7132162006-09-27 01:49:43 -07004395 find_min_pfn_for_node(nid), NULL);
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07004396
4397 /* Any memory on that node */
4398 if (pgdat->node_present_pages)
4399 node_set_state(nid, N_HIGH_MEMORY);
4400 check_for_regular_memory(pgdat);
Mel Gormanc7132162006-09-27 01:49:43 -07004401 }
4402}
Mel Gorman2a1e2742007-07-17 04:03:12 -07004403
Mel Gorman7e63efe2007-07-17 04:03:15 -07004404static int __init cmdline_parse_core(char *p, unsigned long *core)
Mel Gorman2a1e2742007-07-17 04:03:12 -07004405{
4406 unsigned long long coremem;
4407 if (!p)
4408 return -EINVAL;
4409
4410 coremem = memparse(p, &p);
Mel Gorman7e63efe2007-07-17 04:03:15 -07004411 *core = coremem >> PAGE_SHIFT;
Mel Gorman2a1e2742007-07-17 04:03:12 -07004412
Mel Gorman7e63efe2007-07-17 04:03:15 -07004413 /* Paranoid check that UL is enough for the coremem value */
Mel Gorman2a1e2742007-07-17 04:03:12 -07004414 WARN_ON((coremem >> PAGE_SHIFT) > ULONG_MAX);
4415
4416 return 0;
4417}
Mel Gormaned7ed362007-07-17 04:03:14 -07004418
Mel Gorman7e63efe2007-07-17 04:03:15 -07004419/*
4420 * kernelcore=size sets the amount of memory for use for allocations that
4421 * cannot be reclaimed or migrated.
4422 */
4423static int __init cmdline_parse_kernelcore(char *p)
4424{
4425 return cmdline_parse_core(p, &required_kernelcore);
4426}
4427
4428/*
4429 * movablecore=size sets the amount of memory for use for allocations that
4430 * can be reclaimed or migrated.
4431 */
4432static int __init cmdline_parse_movablecore(char *p)
4433{
4434 return cmdline_parse_core(p, &required_movablecore);
4435}
4436
Mel Gormaned7ed362007-07-17 04:03:14 -07004437early_param("kernelcore", cmdline_parse_kernelcore);
Mel Gorman7e63efe2007-07-17 04:03:15 -07004438early_param("movablecore", cmdline_parse_movablecore);
Mel Gormaned7ed362007-07-17 04:03:14 -07004439
Mel Gormanc7132162006-09-27 01:49:43 -07004440#endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
4441
Mel Gorman0e0b8642006-09-27 01:49:56 -07004442/**
Randy Dunlap88ca3b92006-10-04 02:15:25 -07004443 * set_dma_reserve - set the specified number of pages reserved in the first zone
4444 * @new_dma_reserve: The number of pages to mark reserved
Mel Gorman0e0b8642006-09-27 01:49:56 -07004445 *
4446 * The per-cpu batchsize and zone watermarks are determined by present_pages.
4447 * In the DMA zone, a significant percentage may be consumed by kernel image
4448 * and other unfreeable allocations which can skew the watermarks badly. This
Randy Dunlap88ca3b92006-10-04 02:15:25 -07004449 * function may optionally be used to account for unfreeable pages in the
4450 * first zone (e.g., ZONE_DMA). The effect will be lower watermarks and
4451 * smaller per-cpu batchsize.
Mel Gorman0e0b8642006-09-27 01:49:56 -07004452 */
4453void __init set_dma_reserve(unsigned long new_dma_reserve)
4454{
4455 dma_reserve = new_dma_reserve;
4456}
4457
Dave Hansen93b75042005-06-23 00:07:47 -07004458#ifndef CONFIG_NEED_MULTIPLE_NODES
Marcin Slusarz52765582008-09-02 14:35:41 -07004459struct pglist_data __refdata contig_page_data = { .bdata = &bootmem_node_data[0] };
Linus Torvalds1da177e2005-04-16 15:20:36 -07004460EXPORT_SYMBOL(contig_page_data);
Dave Hansen93b75042005-06-23 00:07:47 -07004461#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07004462
4463void __init free_area_init(unsigned long *zones_size)
4464{
Johannes Weiner9109fb72008-07-23 21:27:20 -07004465 free_area_init_node(0, zones_size,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004466 __pa(PAGE_OFFSET) >> PAGE_SHIFT, NULL);
4467}
Linus Torvalds1da177e2005-04-16 15:20:36 -07004468
Linus Torvalds1da177e2005-04-16 15:20:36 -07004469static int page_alloc_cpu_notify(struct notifier_block *self,
4470 unsigned long action, void *hcpu)
4471{
4472 int cpu = (unsigned long)hcpu;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004473
Rafael J. Wysocki8bb78442007-05-09 02:35:10 -07004474 if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) {
Christoph Lameter9f8f2172008-02-04 22:29:11 -08004475 drain_pages(cpu);
4476
4477 /*
4478 * Spill the event counters of the dead processor
4479 * into the current processors event counters.
4480 * This artificially elevates the count of the current
4481 * processor.
4482 */
Christoph Lameterf8891e52006-06-30 01:55:45 -07004483 vm_events_fold_cpu(cpu);
Christoph Lameter9f8f2172008-02-04 22:29:11 -08004484
4485 /*
4486 * Zero the differential counters of the dead processor
4487 * so that the vm statistics are consistent.
4488 *
4489 * This is only okay since the processor is dead and cannot
4490 * race with what we are doing.
4491 */
Christoph Lameter2244b952006-06-30 01:55:33 -07004492 refresh_cpu_vm_stats(cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004493 }
4494 return NOTIFY_OK;
4495}
Linus Torvalds1da177e2005-04-16 15:20:36 -07004496
4497void __init page_alloc_init(void)
4498{
4499 hotcpu_notifier(page_alloc_cpu_notify, 0);
4500}
4501
4502/*
Hideo AOKIcb45b0e2006-04-10 22:52:59 -07004503 * calculate_totalreserve_pages - called when sysctl_lower_zone_reserve_ratio
4504 * or min_free_kbytes changes.
4505 */
4506static void calculate_totalreserve_pages(void)
4507{
4508 struct pglist_data *pgdat;
4509 unsigned long reserve_pages = 0;
Christoph Lameter2f6726e2006-09-25 23:31:18 -07004510 enum zone_type i, j;
Hideo AOKIcb45b0e2006-04-10 22:52:59 -07004511
4512 for_each_online_pgdat(pgdat) {
4513 for (i = 0; i < MAX_NR_ZONES; i++) {
4514 struct zone *zone = pgdat->node_zones + i;
4515 unsigned long max = 0;
4516
4517 /* Find valid and maximum lowmem_reserve in the zone */
4518 for (j = i; j < MAX_NR_ZONES; j++) {
4519 if (zone->lowmem_reserve[j] > max)
4520 max = zone->lowmem_reserve[j];
4521 }
4522
Mel Gorman41858962009-06-16 15:32:12 -07004523 /* we treat the high watermark as reserved pages. */
4524 max += high_wmark_pages(zone);
Hideo AOKIcb45b0e2006-04-10 22:52:59 -07004525
4526 if (max > zone->present_pages)
4527 max = zone->present_pages;
4528 reserve_pages += max;
4529 }
4530 }
4531 totalreserve_pages = reserve_pages;
4532}
4533
4534/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07004535 * setup_per_zone_lowmem_reserve - called whenever
4536 * sysctl_lower_zone_reserve_ratio changes. Ensures that each zone
4537 * has a correct pages reserved value, so an adequate number of
4538 * pages are left in the zone after a successful __alloc_pages().
4539 */
4540static void setup_per_zone_lowmem_reserve(void)
4541{
4542 struct pglist_data *pgdat;
Christoph Lameter2f6726e2006-09-25 23:31:18 -07004543 enum zone_type j, idx;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004544
KAMEZAWA Hiroyukiec936fc2006-03-27 01:15:59 -08004545 for_each_online_pgdat(pgdat) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07004546 for (j = 0; j < MAX_NR_ZONES; j++) {
4547 struct zone *zone = pgdat->node_zones + j;
4548 unsigned long present_pages = zone->present_pages;
4549
4550 zone->lowmem_reserve[j] = 0;
4551
Christoph Lameter2f6726e2006-09-25 23:31:18 -07004552 idx = j;
4553 while (idx) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07004554 struct zone *lower_zone;
4555
Christoph Lameter2f6726e2006-09-25 23:31:18 -07004556 idx--;
4557
Linus Torvalds1da177e2005-04-16 15:20:36 -07004558 if (sysctl_lowmem_reserve_ratio[idx] < 1)
4559 sysctl_lowmem_reserve_ratio[idx] = 1;
4560
4561 lower_zone = pgdat->node_zones + idx;
4562 lower_zone->lowmem_reserve[j] = present_pages /
4563 sysctl_lowmem_reserve_ratio[idx];
4564 present_pages += lower_zone->present_pages;
4565 }
4566 }
4567 }
Hideo AOKIcb45b0e2006-04-10 22:52:59 -07004568
4569 /* update totalreserve_pages */
4570 calculate_totalreserve_pages();
Linus Torvalds1da177e2005-04-16 15:20:36 -07004571}
4572
Randy Dunlap88ca3b92006-10-04 02:15:25 -07004573/**
Minchan Kimbc75d332009-06-16 15:32:48 -07004574 * setup_per_zone_wmarks - called when min_free_kbytes changes
Minchan Kimbce73942009-06-16 15:32:50 -07004575 * or when memory is hot-{added|removed}
Randy Dunlap88ca3b92006-10-04 02:15:25 -07004576 *
Minchan Kimbc75d332009-06-16 15:32:48 -07004577 * Ensures that the watermark[min,low,high] values for each zone are set
4578 * correctly with respect to min_free_kbytes.
Linus Torvalds1da177e2005-04-16 15:20:36 -07004579 */
Minchan Kimbc75d332009-06-16 15:32:48 -07004580void setup_per_zone_wmarks(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -07004581{
4582 unsigned long pages_min = min_free_kbytes >> (PAGE_SHIFT - 10);
4583 unsigned long lowmem_pages = 0;
4584 struct zone *zone;
4585 unsigned long flags;
4586
4587 /* Calculate total number of !ZONE_HIGHMEM pages */
4588 for_each_zone(zone) {
4589 if (!is_highmem(zone))
4590 lowmem_pages += zone->present_pages;
4591 }
4592
4593 for_each_zone(zone) {
Andrew Mortonac924c62006-05-15 09:43:59 -07004594 u64 tmp;
4595
Gerald Schaefer1125b4e2008-10-18 20:27:11 -07004596 spin_lock_irqsave(&zone->lock, flags);
Andrew Mortonac924c62006-05-15 09:43:59 -07004597 tmp = (u64)pages_min * zone->present_pages;
4598 do_div(tmp, lowmem_pages);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004599 if (is_highmem(zone)) {
4600 /*
Nick Piggin669ed172005-11-13 16:06:45 -08004601 * __GFP_HIGH and PF_MEMALLOC allocations usually don't
4602 * need highmem pages, so cap pages_min to a small
4603 * value here.
4604 *
Mel Gorman41858962009-06-16 15:32:12 -07004605 * The WMARK_HIGH-WMARK_LOW and (WMARK_LOW-WMARK_MIN)
Nick Piggin669ed172005-11-13 16:06:45 -08004606 * deltas controls asynch page reclaim, and so should
4607 * not be capped for highmem.
Linus Torvalds1da177e2005-04-16 15:20:36 -07004608 */
4609 int min_pages;
4610
4611 min_pages = zone->present_pages / 1024;
4612 if (min_pages < SWAP_CLUSTER_MAX)
4613 min_pages = SWAP_CLUSTER_MAX;
4614 if (min_pages > 128)
4615 min_pages = 128;
Mel Gorman41858962009-06-16 15:32:12 -07004616 zone->watermark[WMARK_MIN] = min_pages;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004617 } else {
Nick Piggin669ed172005-11-13 16:06:45 -08004618 /*
4619 * If it's a lowmem zone, reserve a number of pages
Linus Torvalds1da177e2005-04-16 15:20:36 -07004620 * proportionate to the zone's size.
4621 */
Mel Gorman41858962009-06-16 15:32:12 -07004622 zone->watermark[WMARK_MIN] = tmp;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004623 }
4624
Mel Gorman41858962009-06-16 15:32:12 -07004625 zone->watermark[WMARK_LOW] = min_wmark_pages(zone) + (tmp >> 2);
4626 zone->watermark[WMARK_HIGH] = min_wmark_pages(zone) + (tmp >> 1);
Mel Gorman56fd56b2007-10-16 01:25:58 -07004627 setup_zone_migrate_reserve(zone);
Gerald Schaefer1125b4e2008-10-18 20:27:11 -07004628 spin_unlock_irqrestore(&zone->lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004629 }
Hideo AOKIcb45b0e2006-04-10 22:52:59 -07004630
4631 /* update totalreserve_pages */
4632 calculate_totalreserve_pages();
Linus Torvalds1da177e2005-04-16 15:20:36 -07004633}
4634
Randy Dunlap55a44622009-09-21 17:01:20 -07004635/*
Rik van Riel556adec2008-10-18 20:26:34 -07004636 * The inactive anon list should be small enough that the VM never has to
4637 * do too much work, but large enough that each inactive page has a chance
4638 * to be referenced again before it is swapped out.
4639 *
4640 * The inactive_anon ratio is the target ratio of ACTIVE_ANON to
4641 * INACTIVE_ANON pages on this zone's LRU, maintained by the
4642 * pageout code. A zone->inactive_ratio of 3 means 3:1 or 25% of
4643 * the anonymous pages are kept on the inactive list.
4644 *
4645 * total target max
4646 * memory ratio inactive anon
4647 * -------------------------------------
4648 * 10MB 1 5MB
4649 * 100MB 1 50MB
4650 * 1GB 3 250MB
4651 * 10GB 10 0.9GB
4652 * 100GB 31 3GB
4653 * 1TB 101 10GB
4654 * 10TB 320 32GB
4655 */
Minchan Kim96cb4df2009-06-16 15:32:49 -07004656void calculate_zone_inactive_ratio(struct zone *zone)
4657{
4658 unsigned int gb, ratio;
4659
4660 /* Zone size in gigabytes */
4661 gb = zone->present_pages >> (30 - PAGE_SHIFT);
4662 if (gb)
4663 ratio = int_sqrt(10 * gb);
4664 else
4665 ratio = 1;
4666
4667 zone->inactive_ratio = ratio;
4668}
4669
Cyrill Gorcunove9bb35d2009-06-16 15:32:32 -07004670static void __init setup_per_zone_inactive_ratio(void)
Rik van Riel556adec2008-10-18 20:26:34 -07004671{
4672 struct zone *zone;
4673
Minchan Kim96cb4df2009-06-16 15:32:49 -07004674 for_each_zone(zone)
4675 calculate_zone_inactive_ratio(zone);
Rik van Riel556adec2008-10-18 20:26:34 -07004676}
4677
Linus Torvalds1da177e2005-04-16 15:20:36 -07004678/*
4679 * Initialise min_free_kbytes.
4680 *
4681 * For small machines we want it small (128k min). For large machines
4682 * we want it large (64MB max). But it is not linear, because network
4683 * bandwidth does not increase linearly with machine size. We use
4684 *
4685 * min_free_kbytes = 4 * sqrt(lowmem_kbytes), for better accuracy:
4686 * min_free_kbytes = sqrt(lowmem_kbytes * 16)
4687 *
4688 * which yields
4689 *
4690 * 16MB: 512k
4691 * 32MB: 724k
4692 * 64MB: 1024k
4693 * 128MB: 1448k
4694 * 256MB: 2048k
4695 * 512MB: 2896k
4696 * 1024MB: 4096k
4697 * 2048MB: 5792k
4698 * 4096MB: 8192k
4699 * 8192MB: 11584k
4700 * 16384MB: 16384k
4701 */
Minchan Kimbc75d332009-06-16 15:32:48 -07004702static int __init init_per_zone_wmark_min(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -07004703{
4704 unsigned long lowmem_kbytes;
4705
4706 lowmem_kbytes = nr_free_buffer_pages() * (PAGE_SIZE >> 10);
4707
4708 min_free_kbytes = int_sqrt(lowmem_kbytes * 16);
4709 if (min_free_kbytes < 128)
4710 min_free_kbytes = 128;
4711 if (min_free_kbytes > 65536)
4712 min_free_kbytes = 65536;
Minchan Kimbc75d332009-06-16 15:32:48 -07004713 setup_per_zone_wmarks();
Linus Torvalds1da177e2005-04-16 15:20:36 -07004714 setup_per_zone_lowmem_reserve();
Rik van Riel556adec2008-10-18 20:26:34 -07004715 setup_per_zone_inactive_ratio();
Linus Torvalds1da177e2005-04-16 15:20:36 -07004716 return 0;
4717}
Minchan Kimbc75d332009-06-16 15:32:48 -07004718module_init(init_per_zone_wmark_min)
Linus Torvalds1da177e2005-04-16 15:20:36 -07004719
4720/*
4721 * min_free_kbytes_sysctl_handler - just a wrapper around proc_dointvec() so
4722 * that we can call two helper functions whenever min_free_kbytes
4723 * changes.
4724 */
4725int min_free_kbytes_sysctl_handler(ctl_table *table, int write,
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07004726 void __user *buffer, size_t *length, loff_t *ppos)
Linus Torvalds1da177e2005-04-16 15:20:36 -07004727{
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07004728 proc_dointvec(table, write, buffer, length, ppos);
Mel Gorman3b1d92c2007-05-06 14:49:30 -07004729 if (write)
Minchan Kimbc75d332009-06-16 15:32:48 -07004730 setup_per_zone_wmarks();
Linus Torvalds1da177e2005-04-16 15:20:36 -07004731 return 0;
4732}
4733
Christoph Lameter96146342006-07-03 00:24:13 -07004734#ifdef CONFIG_NUMA
4735int sysctl_min_unmapped_ratio_sysctl_handler(ctl_table *table, int write,
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07004736 void __user *buffer, size_t *length, loff_t *ppos)
Christoph Lameter96146342006-07-03 00:24:13 -07004737{
4738 struct zone *zone;
4739 int rc;
4740
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07004741 rc = proc_dointvec_minmax(table, write, buffer, length, ppos);
Christoph Lameter96146342006-07-03 00:24:13 -07004742 if (rc)
4743 return rc;
4744
4745 for_each_zone(zone)
Christoph Lameter8417bba2006-09-25 23:31:51 -07004746 zone->min_unmapped_pages = (zone->present_pages *
Christoph Lameter96146342006-07-03 00:24:13 -07004747 sysctl_min_unmapped_ratio) / 100;
4748 return 0;
4749}
Christoph Lameter0ff38492006-09-25 23:31:52 -07004750
4751int sysctl_min_slab_ratio_sysctl_handler(ctl_table *table, int write,
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07004752 void __user *buffer, size_t *length, loff_t *ppos)
Christoph Lameter0ff38492006-09-25 23:31:52 -07004753{
4754 struct zone *zone;
4755 int rc;
4756
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07004757 rc = proc_dointvec_minmax(table, write, buffer, length, ppos);
Christoph Lameter0ff38492006-09-25 23:31:52 -07004758 if (rc)
4759 return rc;
4760
4761 for_each_zone(zone)
4762 zone->min_slab_pages = (zone->present_pages *
4763 sysctl_min_slab_ratio) / 100;
4764 return 0;
4765}
Christoph Lameter96146342006-07-03 00:24:13 -07004766#endif
4767
Linus Torvalds1da177e2005-04-16 15:20:36 -07004768/*
4769 * lowmem_reserve_ratio_sysctl_handler - just a wrapper around
4770 * proc_dointvec() so that we can call setup_per_zone_lowmem_reserve()
4771 * whenever sysctl_lowmem_reserve_ratio changes.
4772 *
4773 * The reserve ratio obviously has absolutely no relation with the
Mel Gorman41858962009-06-16 15:32:12 -07004774 * minimum watermarks. The lowmem reserve ratio can only make sense
Linus Torvalds1da177e2005-04-16 15:20:36 -07004775 * if in function of the boot time zone sizes.
4776 */
4777int lowmem_reserve_ratio_sysctl_handler(ctl_table *table, int write,
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07004778 void __user *buffer, size_t *length, loff_t *ppos)
Linus Torvalds1da177e2005-04-16 15:20:36 -07004779{
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07004780 proc_dointvec_minmax(table, write, buffer, length, ppos);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004781 setup_per_zone_lowmem_reserve();
4782 return 0;
4783}
4784
Rohit Seth8ad4b1f2006-01-08 01:00:40 -08004785/*
4786 * percpu_pagelist_fraction - changes the pcp->high for each zone on each
4787 * cpu. It is the fraction of total pages in each zone that a hot per cpu pagelist
4788 * can have before it gets flushed back to buddy allocator.
4789 */
4790
4791int percpu_pagelist_fraction_sysctl_handler(ctl_table *table, int write,
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07004792 void __user *buffer, size_t *length, loff_t *ppos)
Rohit Seth8ad4b1f2006-01-08 01:00:40 -08004793{
4794 struct zone *zone;
4795 unsigned int cpu;
4796 int ret;
4797
Alexey Dobriyan8d65af72009-09-23 15:57:19 -07004798 ret = proc_dointvec_minmax(table, write, buffer, length, ppos);
Rohit Seth8ad4b1f2006-01-08 01:00:40 -08004799 if (!write || (ret == -EINVAL))
4800 return ret;
Dimitri Sivanich364df0e2009-06-23 12:37:04 -07004801 for_each_populated_zone(zone) {
Rohit Seth8ad4b1f2006-01-08 01:00:40 -08004802 for_each_online_cpu(cpu) {
4803 unsigned long high;
4804 high = zone->present_pages / percpu_pagelist_fraction;
4805 setup_pagelist_highmark(zone_pcp(zone, cpu), high);
4806 }
4807 }
4808 return 0;
4809}
4810
David S. Millerf034b5d2006-08-24 03:08:07 -07004811int hashdist = HASHDIST_DEFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004812
4813#ifdef CONFIG_NUMA
4814static int __init set_hashdist(char *str)
4815{
4816 if (!str)
4817 return 0;
4818 hashdist = simple_strtoul(str, &str, 0);
4819 return 1;
4820}
4821__setup("hashdist=", set_hashdist);
4822#endif
4823
4824/*
4825 * allocate a large system hash table from bootmem
4826 * - it is assumed that the hash table must contain an exact power-of-2
4827 * quantity of entries
4828 * - limit is the number of hash buckets, not the total allocation size
4829 */
4830void *__init alloc_large_system_hash(const char *tablename,
4831 unsigned long bucketsize,
4832 unsigned long numentries,
4833 int scale,
4834 int flags,
4835 unsigned int *_hash_shift,
4836 unsigned int *_hash_mask,
4837 unsigned long limit)
4838{
4839 unsigned long long max = limit;
4840 unsigned long log2qty, size;
4841 void *table = NULL;
4842
4843 /* allow the kernel cmdline to have a say */
4844 if (!numentries) {
4845 /* round applicable memory size up to nearest megabyte */
Andrew Morton04903662006-12-06 20:37:33 -08004846 numentries = nr_kernel_pages;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004847 numentries += (1UL << (20 - PAGE_SHIFT)) - 1;
4848 numentries >>= 20 - PAGE_SHIFT;
4849 numentries <<= 20 - PAGE_SHIFT;
4850
4851 /* limit to 1 bucket per 2^scale bytes of low memory */
4852 if (scale > PAGE_SHIFT)
4853 numentries >>= (scale - PAGE_SHIFT);
4854 else
4855 numentries <<= (PAGE_SHIFT - scale);
Paul Mundt9ab37b82007-01-05 16:36:30 -08004856
4857 /* Make sure we've got at least a 0-order allocation.. */
Jan Beulich2c85f512009-09-21 17:03:07 -07004858 if (unlikely(flags & HASH_SMALL)) {
4859 /* Makes no sense without HASH_EARLY */
4860 WARN_ON(!(flags & HASH_EARLY));
4861 if (!(numentries >> *_hash_shift)) {
4862 numentries = 1UL << *_hash_shift;
4863 BUG_ON(!numentries);
4864 }
4865 } else if (unlikely((numentries * bucketsize) < PAGE_SIZE))
Paul Mundt9ab37b82007-01-05 16:36:30 -08004866 numentries = PAGE_SIZE / bucketsize;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004867 }
John Hawkes6e692ed2006-03-25 03:08:02 -08004868 numentries = roundup_pow_of_two(numentries);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004869
4870 /* limit allocation size to 1/16 total memory by default */
4871 if (max == 0) {
4872 max = ((unsigned long long)nr_all_pages << PAGE_SHIFT) >> 4;
4873 do_div(max, bucketsize);
4874 }
4875
4876 if (numentries > max)
4877 numentries = max;
4878
David Howellsf0d1b0b2006-12-08 02:37:49 -08004879 log2qty = ilog2(numentries);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004880
4881 do {
4882 size = bucketsize << log2qty;
4883 if (flags & HASH_EARLY)
Jan Beulich74768ed2008-08-12 15:08:39 -07004884 table = alloc_bootmem_nopanic(size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004885 else if (hashdist)
4886 table = __vmalloc(size, GFP_ATOMIC, PAGE_KERNEL);
4887 else {
Eric Dumazet1037b832007-07-15 23:38:05 -07004888 /*
4889 * If bucketsize is not a power-of-two, we may free
Mel Gormana1dd2682009-06-16 15:32:19 -07004890 * some pages at the end of hash table which
4891 * alloc_pages_exact() automatically does
Eric Dumazet1037b832007-07-15 23:38:05 -07004892 */
Catalin Marinas264ef8a2009-07-07 10:33:01 +01004893 if (get_order(size) < MAX_ORDER) {
Mel Gormana1dd2682009-06-16 15:32:19 -07004894 table = alloc_pages_exact(size, GFP_ATOMIC);
Catalin Marinas264ef8a2009-07-07 10:33:01 +01004895 kmemleak_alloc(table, size, 1, GFP_ATOMIC);
4896 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07004897 }
4898 } while (!table && size > PAGE_SIZE && --log2qty);
4899
4900 if (!table)
4901 panic("Failed to allocate %s hash table\n", tablename);
4902
Dan Alonib49ad482007-07-15 23:38:23 -07004903 printk(KERN_INFO "%s hash table entries: %d (order: %d, %lu bytes)\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -07004904 tablename,
4905 (1U << log2qty),
David Howellsf0d1b0b2006-12-08 02:37:49 -08004906 ilog2(size) - PAGE_SHIFT,
Linus Torvalds1da177e2005-04-16 15:20:36 -07004907 size);
4908
4909 if (_hash_shift)
4910 *_hash_shift = log2qty;
4911 if (_hash_mask)
4912 *_hash_mask = (1 << log2qty) - 1;
4913
4914 return table;
4915}
KAMEZAWA Hiroyukia117e662006-03-27 01:15:25 -08004916
Mel Gorman835c1342007-10-16 01:25:47 -07004917/* Return a pointer to the bitmap storing bits affecting a block of pages */
4918static inline unsigned long *get_pageblock_bitmap(struct zone *zone,
4919 unsigned long pfn)
4920{
4921#ifdef CONFIG_SPARSEMEM
4922 return __pfn_to_section(pfn)->pageblock_flags;
4923#else
4924 return zone->pageblock_flags;
4925#endif /* CONFIG_SPARSEMEM */
4926}
Andrew Morton6220ec72006-10-19 23:29:05 -07004927
Mel Gorman835c1342007-10-16 01:25:47 -07004928static inline int pfn_to_bitidx(struct zone *zone, unsigned long pfn)
4929{
4930#ifdef CONFIG_SPARSEMEM
4931 pfn &= (PAGES_PER_SECTION-1);
Mel Gormand9c23402007-10-16 01:26:01 -07004932 return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS;
Mel Gorman835c1342007-10-16 01:25:47 -07004933#else
4934 pfn = pfn - zone->zone_start_pfn;
Mel Gormand9c23402007-10-16 01:26:01 -07004935 return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS;
Mel Gorman835c1342007-10-16 01:25:47 -07004936#endif /* CONFIG_SPARSEMEM */
4937}
4938
4939/**
Mel Gormand9c23402007-10-16 01:26:01 -07004940 * 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 -07004941 * @page: The page within the block of interest
4942 * @start_bitidx: The first bit of interest to retrieve
4943 * @end_bitidx: The last bit of interest
4944 * returns pageblock_bits flags
4945 */
4946unsigned long get_pageblock_flags_group(struct page *page,
4947 int start_bitidx, int end_bitidx)
4948{
4949 struct zone *zone;
4950 unsigned long *bitmap;
4951 unsigned long pfn, bitidx;
4952 unsigned long flags = 0;
4953 unsigned long value = 1;
4954
4955 zone = page_zone(page);
4956 pfn = page_to_pfn(page);
4957 bitmap = get_pageblock_bitmap(zone, pfn);
4958 bitidx = pfn_to_bitidx(zone, pfn);
4959
4960 for (; start_bitidx <= end_bitidx; start_bitidx++, value <<= 1)
4961 if (test_bit(bitidx + start_bitidx, bitmap))
4962 flags |= value;
4963
4964 return flags;
4965}
4966
4967/**
Mel Gormand9c23402007-10-16 01:26:01 -07004968 * 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 -07004969 * @page: The page within the block of interest
4970 * @start_bitidx: The first bit of interest
4971 * @end_bitidx: The last bit of interest
4972 * @flags: The flags to set
4973 */
4974void set_pageblock_flags_group(struct page *page, unsigned long flags,
4975 int start_bitidx, int end_bitidx)
4976{
4977 struct zone *zone;
4978 unsigned long *bitmap;
4979 unsigned long pfn, bitidx;
4980 unsigned long value = 1;
4981
4982 zone = page_zone(page);
4983 pfn = page_to_pfn(page);
4984 bitmap = get_pageblock_bitmap(zone, pfn);
4985 bitidx = pfn_to_bitidx(zone, pfn);
KAMEZAWA Hiroyuki86051ca2008-04-29 00:58:21 -07004986 VM_BUG_ON(pfn < zone->zone_start_pfn);
4987 VM_BUG_ON(pfn >= zone->zone_start_pfn + zone->spanned_pages);
Mel Gorman835c1342007-10-16 01:25:47 -07004988
4989 for (; start_bitidx <= end_bitidx; start_bitidx++, value <<= 1)
4990 if (flags & value)
4991 __set_bit(bitidx + start_bitidx, bitmap);
4992 else
4993 __clear_bit(bitidx + start_bitidx, bitmap);
4994}
KAMEZAWA Hiroyukia5d76b52007-10-16 01:26:11 -07004995
4996/*
4997 * This is designed as sub function...plz see page_isolation.c also.
4998 * set/clear page block's type to be ISOLATE.
4999 * page allocater never alloc memory from ISOLATE block.
5000 */
5001
5002int set_migratetype_isolate(struct page *page)
5003{
5004 struct zone *zone;
5005 unsigned long flags;
5006 int ret = -EBUSY;
Shaohua Li8e7e40d2009-09-21 17:01:18 -07005007 int zone_idx;
KAMEZAWA Hiroyukia5d76b52007-10-16 01:26:11 -07005008
5009 zone = page_zone(page);
Shaohua Li8e7e40d2009-09-21 17:01:18 -07005010 zone_idx = zone_idx(zone);
KAMEZAWA Hiroyukia5d76b52007-10-16 01:26:11 -07005011 spin_lock_irqsave(&zone->lock, flags);
5012 /*
5013 * In future, more migrate types will be able to be isolation target.
5014 */
Shaohua Li8e7e40d2009-09-21 17:01:18 -07005015 if (get_pageblock_migratetype(page) != MIGRATE_MOVABLE &&
5016 zone_idx != ZONE_MOVABLE)
KAMEZAWA Hiroyukia5d76b52007-10-16 01:26:11 -07005017 goto out;
5018 set_pageblock_migratetype(page, MIGRATE_ISOLATE);
5019 move_freepages_block(zone, page, MIGRATE_ISOLATE);
5020 ret = 0;
5021out:
5022 spin_unlock_irqrestore(&zone->lock, flags);
5023 if (!ret)
Christoph Lameter9f8f2172008-02-04 22:29:11 -08005024 drain_all_pages();
KAMEZAWA Hiroyukia5d76b52007-10-16 01:26:11 -07005025 return ret;
5026}
5027
5028void unset_migratetype_isolate(struct page *page)
5029{
5030 struct zone *zone;
5031 unsigned long flags;
5032 zone = page_zone(page);
5033 spin_lock_irqsave(&zone->lock, flags);
5034 if (get_pageblock_migratetype(page) != MIGRATE_ISOLATE)
5035 goto out;
5036 set_pageblock_migratetype(page, MIGRATE_MOVABLE);
5037 move_freepages_block(zone, page, MIGRATE_MOVABLE);
5038out:
5039 spin_unlock_irqrestore(&zone->lock, flags);
5040}
KAMEZAWA Hiroyuki0c0e6192007-10-16 01:26:12 -07005041
5042#ifdef CONFIG_MEMORY_HOTREMOVE
5043/*
5044 * All pages in the range must be isolated before calling this.
5045 */
5046void
5047__offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
5048{
5049 struct page *page;
5050 struct zone *zone;
5051 int order, i;
5052 unsigned long pfn;
5053 unsigned long flags;
5054 /* find the first valid pfn */
5055 for (pfn = start_pfn; pfn < end_pfn; pfn++)
5056 if (pfn_valid(pfn))
5057 break;
5058 if (pfn == end_pfn)
5059 return;
5060 zone = page_zone(pfn_to_page(pfn));
5061 spin_lock_irqsave(&zone->lock, flags);
5062 pfn = start_pfn;
5063 while (pfn < end_pfn) {
5064 if (!pfn_valid(pfn)) {
5065 pfn++;
5066 continue;
5067 }
5068 page = pfn_to_page(pfn);
5069 BUG_ON(page_count(page));
5070 BUG_ON(!PageBuddy(page));
5071 order = page_order(page);
5072#ifdef CONFIG_DEBUG_VM
5073 printk(KERN_INFO "remove from free list %lx %d %lx\n",
5074 pfn, 1 << order, end_pfn);
5075#endif
5076 list_del(&page->lru);
5077 rmv_page_order(page);
5078 zone->free_area[order].nr_free--;
5079 __mod_zone_page_state(zone, NR_FREE_PAGES,
5080 - (1UL << order));
5081 for (i = 0; i < (1 << order); i++)
5082 SetPageReserved((page+i));
5083 pfn += (1 << order);
5084 }
5085 spin_unlock_irqrestore(&zone->lock, flags);
5086}
5087#endif