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![KOSAKI Motohiro](/assets/img/avatar_default.png)
Currently, nobody wants to turn UNEVICTABLE_LRU off. Thus this configurability is unnecessary. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Andi Kleen <andi@firstfloor.org> Acked-by: Minchan Kim <minchan.kim@gmail.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Matt Mackall <mpm@selenic.com> Cc: Rik van Riel <riel@redhat.com> Cc: Lee Schermerhorn <lee.schermerhorn@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1126 lines
35 KiB
C
1126 lines
35 KiB
C
#ifndef _LINUX_MMZONE_H
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#define _LINUX_MMZONE_H
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#ifndef __ASSEMBLY__
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#ifndef __GENERATING_BOUNDS_H
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#include <linux/spinlock.h>
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#include <linux/list.h>
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#include <linux/wait.h>
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#include <linux/bitops.h>
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#include <linux/cache.h>
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#include <linux/threads.h>
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#include <linux/numa.h>
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#include <linux/init.h>
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#include <linux/seqlock.h>
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#include <linux/nodemask.h>
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#include <linux/pageblock-flags.h>
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#include <linux/bounds.h>
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#include <asm/atomic.h>
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#include <asm/page.h>
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/* Free memory management - zoned buddy allocator. */
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#ifndef CONFIG_FORCE_MAX_ZONEORDER
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#define MAX_ORDER 11
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#else
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#define MAX_ORDER CONFIG_FORCE_MAX_ZONEORDER
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#endif
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#define MAX_ORDER_NR_PAGES (1 << (MAX_ORDER - 1))
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/*
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* PAGE_ALLOC_COSTLY_ORDER is the order at which allocations are deemed
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* costly to service. That is between allocation orders which should
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* coelesce naturally under reasonable reclaim pressure and those which
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* will not.
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*/
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#define PAGE_ALLOC_COSTLY_ORDER 3
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#define MIGRATE_UNMOVABLE 0
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#define MIGRATE_RECLAIMABLE 1
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#define MIGRATE_MOVABLE 2
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#define MIGRATE_RESERVE 3
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#define MIGRATE_ISOLATE 4 /* can't allocate from here */
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#define MIGRATE_TYPES 5
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#define for_each_migratetype_order(order, type) \
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for (order = 0; order < MAX_ORDER; order++) \
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for (type = 0; type < MIGRATE_TYPES; type++)
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extern int page_group_by_mobility_disabled;
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static inline int get_pageblock_migratetype(struct page *page)
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{
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return get_pageblock_flags_group(page, PB_migrate, PB_migrate_end);
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}
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struct free_area {
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struct list_head free_list[MIGRATE_TYPES];
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unsigned long nr_free;
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};
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struct pglist_data;
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/*
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* zone->lock and zone->lru_lock are two of the hottest locks in the kernel.
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* So add a wild amount of padding here to ensure that they fall into separate
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* cachelines. There are very few zone structures in the machine, so space
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* consumption is not a concern here.
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*/
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#if defined(CONFIG_SMP)
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struct zone_padding {
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char x[0];
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} ____cacheline_internodealigned_in_smp;
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#define ZONE_PADDING(name) struct zone_padding name;
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#else
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#define ZONE_PADDING(name)
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#endif
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enum zone_stat_item {
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/* First 128 byte cacheline (assuming 64 bit words) */
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NR_FREE_PAGES,
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NR_LRU_BASE,
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NR_INACTIVE_ANON = NR_LRU_BASE, /* must match order of LRU_[IN]ACTIVE */
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NR_ACTIVE_ANON, /* " " " " " */
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NR_INACTIVE_FILE, /* " " " " " */
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NR_ACTIVE_FILE, /* " " " " " */
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NR_UNEVICTABLE, /* " " " " " */
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NR_MLOCK, /* mlock()ed pages found and moved off LRU */
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NR_ANON_PAGES, /* Mapped anonymous pages */
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NR_FILE_MAPPED, /* pagecache pages mapped into pagetables.
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only modified from process context */
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NR_FILE_PAGES,
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NR_FILE_DIRTY,
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NR_WRITEBACK,
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NR_SLAB_RECLAIMABLE,
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NR_SLAB_UNRECLAIMABLE,
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NR_PAGETABLE, /* used for pagetables */
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NR_UNSTABLE_NFS, /* NFS unstable pages */
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NR_BOUNCE,
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NR_VMSCAN_WRITE,
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/* Second 128 byte cacheline */
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NR_WRITEBACK_TEMP, /* Writeback using temporary buffers */
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#ifdef CONFIG_NUMA
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NUMA_HIT, /* allocated in intended node */
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NUMA_MISS, /* allocated in non intended node */
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NUMA_FOREIGN, /* was intended here, hit elsewhere */
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NUMA_INTERLEAVE_HIT, /* interleaver preferred this zone */
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NUMA_LOCAL, /* allocation from local node */
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NUMA_OTHER, /* allocation from other node */
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#endif
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NR_VM_ZONE_STAT_ITEMS };
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/*
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* We do arithmetic on the LRU lists in various places in the code,
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* so it is important to keep the active lists LRU_ACTIVE higher in
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* the array than the corresponding inactive lists, and to keep
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* the *_FILE lists LRU_FILE higher than the corresponding _ANON lists.
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*
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* This has to be kept in sync with the statistics in zone_stat_item
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* above and the descriptions in vmstat_text in mm/vmstat.c
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*/
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#define LRU_BASE 0
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#define LRU_ACTIVE 1
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#define LRU_FILE 2
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enum lru_list {
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LRU_INACTIVE_ANON = LRU_BASE,
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LRU_ACTIVE_ANON = LRU_BASE + LRU_ACTIVE,
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LRU_INACTIVE_FILE = LRU_BASE + LRU_FILE,
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LRU_ACTIVE_FILE = LRU_BASE + LRU_FILE + LRU_ACTIVE,
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LRU_UNEVICTABLE,
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NR_LRU_LISTS
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};
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#define for_each_lru(l) for (l = 0; l < NR_LRU_LISTS; l++)
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#define for_each_evictable_lru(l) for (l = 0; l <= LRU_ACTIVE_FILE; l++)
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static inline int is_file_lru(enum lru_list l)
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{
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return (l == LRU_INACTIVE_FILE || l == LRU_ACTIVE_FILE);
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}
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static inline int is_active_lru(enum lru_list l)
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{
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return (l == LRU_ACTIVE_ANON || l == LRU_ACTIVE_FILE);
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}
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static inline int is_unevictable_lru(enum lru_list l)
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{
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return (l == LRU_UNEVICTABLE);
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}
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enum zone_watermarks {
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WMARK_MIN,
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WMARK_LOW,
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WMARK_HIGH,
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NR_WMARK
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};
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#define min_wmark_pages(z) (z->watermark[WMARK_MIN])
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#define low_wmark_pages(z) (z->watermark[WMARK_LOW])
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#define high_wmark_pages(z) (z->watermark[WMARK_HIGH])
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struct per_cpu_pages {
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int count; /* number of pages in the list */
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int high; /* high watermark, emptying needed */
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int batch; /* chunk size for buddy add/remove */
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struct list_head list; /* the list of pages */
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};
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struct per_cpu_pageset {
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struct per_cpu_pages pcp;
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#ifdef CONFIG_NUMA
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s8 expire;
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#endif
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#ifdef CONFIG_SMP
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s8 stat_threshold;
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s8 vm_stat_diff[NR_VM_ZONE_STAT_ITEMS];
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#endif
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} ____cacheline_aligned_in_smp;
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#ifdef CONFIG_NUMA
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#define zone_pcp(__z, __cpu) ((__z)->pageset[(__cpu)])
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#else
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#define zone_pcp(__z, __cpu) (&(__z)->pageset[(__cpu)])
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#endif
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#endif /* !__GENERATING_BOUNDS.H */
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enum zone_type {
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#ifdef CONFIG_ZONE_DMA
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/*
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* ZONE_DMA is used when there are devices that are not able
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* to do DMA to all of addressable memory (ZONE_NORMAL). Then we
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* carve out the portion of memory that is needed for these devices.
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* The range is arch specific.
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*
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* Some examples
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*
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* Architecture Limit
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* ---------------------------
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* parisc, ia64, sparc <4G
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* s390 <2G
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* arm Various
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* alpha Unlimited or 0-16MB.
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*
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* i386, x86_64 and multiple other arches
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* <16M.
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*/
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ZONE_DMA,
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#endif
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#ifdef CONFIG_ZONE_DMA32
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/*
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* x86_64 needs two ZONE_DMAs because it supports devices that are
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* only able to do DMA to the lower 16M but also 32 bit devices that
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* can only do DMA areas below 4G.
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*/
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ZONE_DMA32,
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#endif
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/*
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* Normal addressable memory is in ZONE_NORMAL. DMA operations can be
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* performed on pages in ZONE_NORMAL if the DMA devices support
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* transfers to all addressable memory.
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*/
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ZONE_NORMAL,
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#ifdef CONFIG_HIGHMEM
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/*
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* A memory area that is only addressable by the kernel through
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* mapping portions into its own address space. This is for example
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* used by i386 to allow the kernel to address the memory beyond
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* 900MB. The kernel will set up special mappings (page
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* table entries on i386) for each page that the kernel needs to
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* access.
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*/
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ZONE_HIGHMEM,
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#endif
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ZONE_MOVABLE,
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__MAX_NR_ZONES
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};
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#ifndef __GENERATING_BOUNDS_H
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/*
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* When a memory allocation must conform to specific limitations (such
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* as being suitable for DMA) the caller will pass in hints to the
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* allocator in the gfp_mask, in the zone modifier bits. These bits
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* are used to select a priority ordered list of memory zones which
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* match the requested limits. See gfp_zone() in include/linux/gfp.h
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*/
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#if MAX_NR_ZONES < 2
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#define ZONES_SHIFT 0
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#elif MAX_NR_ZONES <= 2
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#define ZONES_SHIFT 1
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#elif MAX_NR_ZONES <= 4
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#define ZONES_SHIFT 2
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#else
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#error ZONES_SHIFT -- too many zones configured adjust calculation
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#endif
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struct zone_reclaim_stat {
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/*
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* The pageout code in vmscan.c keeps track of how many of the
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* mem/swap backed and file backed pages are refeferenced.
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* The higher the rotated/scanned ratio, the more valuable
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* that cache is.
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*
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* The anon LRU stats live in [0], file LRU stats in [1]
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*/
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unsigned long recent_rotated[2];
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unsigned long recent_scanned[2];
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};
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struct zone {
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/* Fields commonly accessed by the page allocator */
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/* zone watermarks, access with *_wmark_pages(zone) macros */
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unsigned long watermark[NR_WMARK];
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/*
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* We don't know if the memory that we're going to allocate will be freeable
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* or/and it will be released eventually, so to avoid totally wasting several
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* GB of ram we must reserve some of the lower zone memory (otherwise we risk
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* to run OOM on the lower zones despite there's tons of freeable ram
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* on the higher zones). This array is recalculated at runtime if the
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* sysctl_lowmem_reserve_ratio sysctl changes.
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*/
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unsigned long lowmem_reserve[MAX_NR_ZONES];
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#ifdef CONFIG_NUMA
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int node;
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/*
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* zone reclaim becomes active if more unmapped pages exist.
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*/
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unsigned long min_unmapped_pages;
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unsigned long min_slab_pages;
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struct per_cpu_pageset *pageset[NR_CPUS];
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#else
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struct per_cpu_pageset pageset[NR_CPUS];
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#endif
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/*
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* free areas of different sizes
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*/
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spinlock_t lock;
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#ifdef CONFIG_MEMORY_HOTPLUG
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/* see spanned/present_pages for more description */
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seqlock_t span_seqlock;
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#endif
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struct free_area free_area[MAX_ORDER];
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#ifndef CONFIG_SPARSEMEM
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/*
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* Flags for a pageblock_nr_pages block. See pageblock-flags.h.
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* In SPARSEMEM, this map is stored in struct mem_section
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*/
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unsigned long *pageblock_flags;
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#endif /* CONFIG_SPARSEMEM */
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ZONE_PADDING(_pad1_)
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/* Fields commonly accessed by the page reclaim scanner */
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spinlock_t lru_lock;
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struct zone_lru {
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struct list_head list;
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unsigned long nr_saved_scan; /* accumulated for batching */
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} lru[NR_LRU_LISTS];
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struct zone_reclaim_stat reclaim_stat;
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unsigned long pages_scanned; /* since last reclaim */
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unsigned long flags; /* zone flags, see below */
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/* Zone statistics */
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atomic_long_t vm_stat[NR_VM_ZONE_STAT_ITEMS];
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/*
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* prev_priority holds the scanning priority for this zone. It is
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* defined as the scanning priority at which we achieved our reclaim
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* target at the previous try_to_free_pages() or balance_pgdat()
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* invokation.
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*
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* We use prev_priority as a measure of how much stress page reclaim is
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* under - it drives the swappiness decision: whether to unmap mapped
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* pages.
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*
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* Access to both this field is quite racy even on uniprocessor. But
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* it is expected to average out OK.
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*/
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int prev_priority;
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/*
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* The target ratio of ACTIVE_ANON to INACTIVE_ANON pages on
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* this zone's LRU. Maintained by the pageout code.
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*/
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unsigned int inactive_ratio;
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ZONE_PADDING(_pad2_)
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/* Rarely used or read-mostly fields */
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/*
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* wait_table -- the array holding the hash table
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* wait_table_hash_nr_entries -- the size of the hash table array
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* wait_table_bits -- wait_table_size == (1 << wait_table_bits)
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*
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* The purpose of all these is to keep track of the people
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* waiting for a page to become available and make them
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* runnable again when possible. The trouble is that this
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* consumes a lot of space, especially when so few things
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* wait on pages at a given time. So instead of using
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* per-page waitqueues, we use a waitqueue hash table.
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*
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* The bucket discipline is to sleep on the same queue when
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* colliding and wake all in that wait queue when removing.
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* When something wakes, it must check to be sure its page is
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* truly available, a la thundering herd. The cost of a
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* collision is great, but given the expected load of the
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* table, they should be so rare as to be outweighed by the
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* benefits from the saved space.
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*
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* __wait_on_page_locked() and unlock_page() in mm/filemap.c, are the
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* primary users of these fields, and in mm/page_alloc.c
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* free_area_init_core() performs the initialization of them.
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*/
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wait_queue_head_t * wait_table;
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unsigned long wait_table_hash_nr_entries;
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unsigned long wait_table_bits;
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/*
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* Discontig memory support fields.
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*/
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struct pglist_data *zone_pgdat;
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/* zone_start_pfn == zone_start_paddr >> PAGE_SHIFT */
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unsigned long zone_start_pfn;
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/*
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* zone_start_pfn, spanned_pages and present_pages are all
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* protected by span_seqlock. It is a seqlock because it has
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* to be read outside of zone->lock, and it is done in the main
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* allocator path. But, it is written quite infrequently.
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*
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* The lock is declared along with zone->lock because it is
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* frequently read in proximity to zone->lock. It's good to
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* give them a chance of being in the same cacheline.
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*/
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unsigned long spanned_pages; /* total size, including holes */
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unsigned long present_pages; /* amount of memory (excluding holes) */
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/*
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* rarely used fields:
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*/
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const char *name;
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} ____cacheline_internodealigned_in_smp;
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typedef enum {
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ZONE_ALL_UNRECLAIMABLE, /* all pages pinned */
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ZONE_RECLAIM_LOCKED, /* prevents concurrent reclaim */
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ZONE_OOM_LOCKED, /* zone is in OOM killer zonelist */
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} zone_flags_t;
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static inline void zone_set_flag(struct zone *zone, zone_flags_t flag)
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{
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set_bit(flag, &zone->flags);
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}
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static inline int zone_test_and_set_flag(struct zone *zone, zone_flags_t flag)
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{
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return test_and_set_bit(flag, &zone->flags);
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}
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static inline void zone_clear_flag(struct zone *zone, zone_flags_t flag)
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{
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clear_bit(flag, &zone->flags);
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}
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static inline int zone_is_all_unreclaimable(const struct zone *zone)
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{
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return test_bit(ZONE_ALL_UNRECLAIMABLE, &zone->flags);
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}
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static inline int zone_is_reclaim_locked(const struct zone *zone)
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{
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return test_bit(ZONE_RECLAIM_LOCKED, &zone->flags);
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}
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static inline int zone_is_oom_locked(const struct zone *zone)
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{
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return test_bit(ZONE_OOM_LOCKED, &zone->flags);
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}
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/*
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* The "priority" of VM scanning is how much of the queues we will scan in one
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* go. A value of 12 for DEF_PRIORITY implies that we will scan 1/4096th of the
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* queues ("queue_length >> 12") during an aging round.
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*/
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#define DEF_PRIORITY 12
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/* Maximum number of zones on a zonelist */
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#define MAX_ZONES_PER_ZONELIST (MAX_NUMNODES * MAX_NR_ZONES)
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#ifdef CONFIG_NUMA
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/*
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* The NUMA zonelists are doubled becausse we need zonelists that restrict the
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* allocations to a single node for GFP_THISNODE.
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*
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* [0] : Zonelist with fallback
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* [1] : No fallback (GFP_THISNODE)
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*/
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#define MAX_ZONELISTS 2
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|
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/*
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* We cache key information from each zonelist for smaller cache
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|
* footprint when scanning for free pages in get_page_from_freelist().
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*
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* 1) The BITMAP fullzones tracks which zones in a zonelist have come
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* up short of free memory since the last time (last_fullzone_zap)
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* we zero'd fullzones.
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* 2) The array z_to_n[] maps each zone in the zonelist to its node
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* id, so that we can efficiently evaluate whether that node is
|
|
* set in the current tasks mems_allowed.
|
|
*
|
|
* Both fullzones and z_to_n[] are one-to-one with the zonelist,
|
|
* indexed by a zones offset in the zonelist zones[] array.
|
|
*
|
|
* The get_page_from_freelist() routine does two scans. During the
|
|
* first scan, we skip zones whose corresponding bit in 'fullzones'
|
|
* is set or whose corresponding node in current->mems_allowed (which
|
|
* comes from cpusets) is not set. During the second scan, we bypass
|
|
* this zonelist_cache, to ensure we look methodically at each zone.
|
|
*
|
|
* Once per second, we zero out (zap) fullzones, forcing us to
|
|
* reconsider nodes that might have regained more free memory.
|
|
* The field last_full_zap is the time we last zapped fullzones.
|
|
*
|
|
* This mechanism reduces the amount of time we waste repeatedly
|
|
* reexaming zones for free memory when they just came up low on
|
|
* memory momentarilly ago.
|
|
*
|
|
* The zonelist_cache struct members logically belong in struct
|
|
* zonelist. However, the mempolicy zonelists constructed for
|
|
* MPOL_BIND are intentionally variable length (and usually much
|
|
* shorter). A general purpose mechanism for handling structs with
|
|
* multiple variable length members is more mechanism than we want
|
|
* here. We resort to some special case hackery instead.
|
|
*
|
|
* The MPOL_BIND zonelists don't need this zonelist_cache (in good
|
|
* part because they are shorter), so we put the fixed length stuff
|
|
* at the front of the zonelist struct, ending in a variable length
|
|
* zones[], as is needed by MPOL_BIND.
|
|
*
|
|
* Then we put the optional zonelist cache on the end of the zonelist
|
|
* struct. This optional stuff is found by a 'zlcache_ptr' pointer in
|
|
* the fixed length portion at the front of the struct. This pointer
|
|
* both enables us to find the zonelist cache, and in the case of
|
|
* MPOL_BIND zonelists, (which will just set the zlcache_ptr to NULL)
|
|
* to know that the zonelist cache is not there.
|
|
*
|
|
* The end result is that struct zonelists come in two flavors:
|
|
* 1) The full, fixed length version, shown below, and
|
|
* 2) The custom zonelists for MPOL_BIND.
|
|
* The custom MPOL_BIND zonelists have a NULL zlcache_ptr and no zlcache.
|
|
*
|
|
* Even though there may be multiple CPU cores on a node modifying
|
|
* fullzones or last_full_zap in the same zonelist_cache at the same
|
|
* time, we don't lock it. This is just hint data - if it is wrong now
|
|
* and then, the allocator will still function, perhaps a bit slower.
|
|
*/
|
|
|
|
|
|
struct zonelist_cache {
|
|
unsigned short z_to_n[MAX_ZONES_PER_ZONELIST]; /* zone->nid */
|
|
DECLARE_BITMAP(fullzones, MAX_ZONES_PER_ZONELIST); /* zone full? */
|
|
unsigned long last_full_zap; /* when last zap'd (jiffies) */
|
|
};
|
|
#else
|
|
#define MAX_ZONELISTS 1
|
|
struct zonelist_cache;
|
|
#endif
|
|
|
|
/*
|
|
* This struct contains information about a zone in a zonelist. It is stored
|
|
* here to avoid dereferences into large structures and lookups of tables
|
|
*/
|
|
struct zoneref {
|
|
struct zone *zone; /* Pointer to actual zone */
|
|
int zone_idx; /* zone_idx(zoneref->zone) */
|
|
};
|
|
|
|
/*
|
|
* One allocation request operates on a zonelist. A zonelist
|
|
* is a list of zones, the first one is the 'goal' of the
|
|
* allocation, the other zones are fallback zones, in decreasing
|
|
* priority.
|
|
*
|
|
* If zlcache_ptr is not NULL, then it is just the address of zlcache,
|
|
* as explained above. If zlcache_ptr is NULL, there is no zlcache.
|
|
* *
|
|
* To speed the reading of the zonelist, the zonerefs contain the zone index
|
|
* of the entry being read. Helper functions to access information given
|
|
* a struct zoneref are
|
|
*
|
|
* zonelist_zone() - Return the struct zone * for an entry in _zonerefs
|
|
* zonelist_zone_idx() - Return the index of the zone for an entry
|
|
* zonelist_node_idx() - Return the index of the node for an entry
|
|
*/
|
|
struct zonelist {
|
|
struct zonelist_cache *zlcache_ptr; // NULL or &zlcache
|
|
struct zoneref _zonerefs[MAX_ZONES_PER_ZONELIST + 1];
|
|
#ifdef CONFIG_NUMA
|
|
struct zonelist_cache zlcache; // optional ...
|
|
#endif
|
|
};
|
|
|
|
#ifdef CONFIG_ARCH_POPULATES_NODE_MAP
|
|
struct node_active_region {
|
|
unsigned long start_pfn;
|
|
unsigned long end_pfn;
|
|
int nid;
|
|
};
|
|
#endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
|
|
|
|
#ifndef CONFIG_DISCONTIGMEM
|
|
/* The array of struct pages - for discontigmem use pgdat->lmem_map */
|
|
extern struct page *mem_map;
|
|
#endif
|
|
|
|
/*
|
|
* The pg_data_t structure is used in machines with CONFIG_DISCONTIGMEM
|
|
* (mostly NUMA machines?) to denote a higher-level memory zone than the
|
|
* zone denotes.
|
|
*
|
|
* On NUMA machines, each NUMA node would have a pg_data_t to describe
|
|
* it's memory layout.
|
|
*
|
|
* Memory statistics and page replacement data structures are maintained on a
|
|
* per-zone basis.
|
|
*/
|
|
struct bootmem_data;
|
|
typedef struct pglist_data {
|
|
struct zone node_zones[MAX_NR_ZONES];
|
|
struct zonelist node_zonelists[MAX_ZONELISTS];
|
|
int nr_zones;
|
|
#ifdef CONFIG_FLAT_NODE_MEM_MAP /* means !SPARSEMEM */
|
|
struct page *node_mem_map;
|
|
#ifdef CONFIG_CGROUP_MEM_RES_CTLR
|
|
struct page_cgroup *node_page_cgroup;
|
|
#endif
|
|
#endif
|
|
struct bootmem_data *bdata;
|
|
#ifdef CONFIG_MEMORY_HOTPLUG
|
|
/*
|
|
* Must be held any time you expect node_start_pfn, node_present_pages
|
|
* or node_spanned_pages stay constant. Holding this will also
|
|
* guarantee that any pfn_valid() stays that way.
|
|
*
|
|
* Nests above zone->lock and zone->size_seqlock.
|
|
*/
|
|
spinlock_t node_size_lock;
|
|
#endif
|
|
unsigned long node_start_pfn;
|
|
unsigned long node_present_pages; /* total number of physical pages */
|
|
unsigned long node_spanned_pages; /* total size of physical page
|
|
range, including holes */
|
|
int node_id;
|
|
wait_queue_head_t kswapd_wait;
|
|
struct task_struct *kswapd;
|
|
int kswapd_max_order;
|
|
} pg_data_t;
|
|
|
|
#define node_present_pages(nid) (NODE_DATA(nid)->node_present_pages)
|
|
#define node_spanned_pages(nid) (NODE_DATA(nid)->node_spanned_pages)
|
|
#ifdef CONFIG_FLAT_NODE_MEM_MAP
|
|
#define pgdat_page_nr(pgdat, pagenr) ((pgdat)->node_mem_map + (pagenr))
|
|
#else
|
|
#define pgdat_page_nr(pgdat, pagenr) pfn_to_page((pgdat)->node_start_pfn + (pagenr))
|
|
#endif
|
|
#define nid_page_nr(nid, pagenr) pgdat_page_nr(NODE_DATA(nid),(pagenr))
|
|
|
|
#include <linux/memory_hotplug.h>
|
|
|
|
void get_zone_counts(unsigned long *active, unsigned long *inactive,
|
|
unsigned long *free);
|
|
void build_all_zonelists(void);
|
|
void wakeup_kswapd(struct zone *zone, int order);
|
|
int zone_watermark_ok(struct zone *z, int order, unsigned long mark,
|
|
int classzone_idx, int alloc_flags);
|
|
enum memmap_context {
|
|
MEMMAP_EARLY,
|
|
MEMMAP_HOTPLUG,
|
|
};
|
|
extern int init_currently_empty_zone(struct zone *zone, unsigned long start_pfn,
|
|
unsigned long size,
|
|
enum memmap_context context);
|
|
|
|
#ifdef CONFIG_HAVE_MEMORY_PRESENT
|
|
void memory_present(int nid, unsigned long start, unsigned long end);
|
|
#else
|
|
static inline void memory_present(int nid, unsigned long start, unsigned long end) {}
|
|
#endif
|
|
|
|
#ifdef CONFIG_NEED_NODE_MEMMAP_SIZE
|
|
unsigned long __init node_memmap_size_bytes(int, unsigned long, unsigned long);
|
|
#endif
|
|
|
|
/*
|
|
* zone_idx() returns 0 for the ZONE_DMA zone, 1 for the ZONE_NORMAL zone, etc.
|
|
*/
|
|
#define zone_idx(zone) ((zone) - (zone)->zone_pgdat->node_zones)
|
|
|
|
static inline int populated_zone(struct zone *zone)
|
|
{
|
|
return (!!zone->present_pages);
|
|
}
|
|
|
|
extern int movable_zone;
|
|
|
|
static inline int zone_movable_is_highmem(void)
|
|
{
|
|
#if defined(CONFIG_HIGHMEM) && defined(CONFIG_ARCH_POPULATES_NODE_MAP)
|
|
return movable_zone == ZONE_HIGHMEM;
|
|
#else
|
|
return 0;
|
|
#endif
|
|
}
|
|
|
|
static inline int is_highmem_idx(enum zone_type idx)
|
|
{
|
|
#ifdef CONFIG_HIGHMEM
|
|
return (idx == ZONE_HIGHMEM ||
|
|
(idx == ZONE_MOVABLE && zone_movable_is_highmem()));
|
|
#else
|
|
return 0;
|
|
#endif
|
|
}
|
|
|
|
static inline int is_normal_idx(enum zone_type idx)
|
|
{
|
|
return (idx == ZONE_NORMAL);
|
|
}
|
|
|
|
/**
|
|
* is_highmem - helper function to quickly check if a struct zone is a
|
|
* highmem zone or not. This is an attempt to keep references
|
|
* to ZONE_{DMA/NORMAL/HIGHMEM/etc} in general code to a minimum.
|
|
* @zone - pointer to struct zone variable
|
|
*/
|
|
static inline int is_highmem(struct zone *zone)
|
|
{
|
|
#ifdef CONFIG_HIGHMEM
|
|
int zone_off = (char *)zone - (char *)zone->zone_pgdat->node_zones;
|
|
return zone_off == ZONE_HIGHMEM * sizeof(*zone) ||
|
|
(zone_off == ZONE_MOVABLE * sizeof(*zone) &&
|
|
zone_movable_is_highmem());
|
|
#else
|
|
return 0;
|
|
#endif
|
|
}
|
|
|
|
static inline int is_normal(struct zone *zone)
|
|
{
|
|
return zone == zone->zone_pgdat->node_zones + ZONE_NORMAL;
|
|
}
|
|
|
|
static inline int is_dma32(struct zone *zone)
|
|
{
|
|
#ifdef CONFIG_ZONE_DMA32
|
|
return zone == zone->zone_pgdat->node_zones + ZONE_DMA32;
|
|
#else
|
|
return 0;
|
|
#endif
|
|
}
|
|
|
|
static inline int is_dma(struct zone *zone)
|
|
{
|
|
#ifdef CONFIG_ZONE_DMA
|
|
return zone == zone->zone_pgdat->node_zones + ZONE_DMA;
|
|
#else
|
|
return 0;
|
|
#endif
|
|
}
|
|
|
|
/* These two functions are used to setup the per zone pages min values */
|
|
struct ctl_table;
|
|
struct file;
|
|
int min_free_kbytes_sysctl_handler(struct ctl_table *, int, struct file *,
|
|
void __user *, size_t *, loff_t *);
|
|
extern int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES-1];
|
|
int lowmem_reserve_ratio_sysctl_handler(struct ctl_table *, int, struct file *,
|
|
void __user *, size_t *, loff_t *);
|
|
int percpu_pagelist_fraction_sysctl_handler(struct ctl_table *, int, struct file *,
|
|
void __user *, size_t *, loff_t *);
|
|
int sysctl_min_unmapped_ratio_sysctl_handler(struct ctl_table *, int,
|
|
struct file *, void __user *, size_t *, loff_t *);
|
|
int sysctl_min_slab_ratio_sysctl_handler(struct ctl_table *, int,
|
|
struct file *, void __user *, size_t *, loff_t *);
|
|
|
|
extern int numa_zonelist_order_handler(struct ctl_table *, int,
|
|
struct file *, void __user *, size_t *, loff_t *);
|
|
extern char numa_zonelist_order[];
|
|
#define NUMA_ZONELIST_ORDER_LEN 16 /* string buffer size */
|
|
|
|
#ifndef CONFIG_NEED_MULTIPLE_NODES
|
|
|
|
extern struct pglist_data contig_page_data;
|
|
#define NODE_DATA(nid) (&contig_page_data)
|
|
#define NODE_MEM_MAP(nid) mem_map
|
|
|
|
#else /* CONFIG_NEED_MULTIPLE_NODES */
|
|
|
|
#include <asm/mmzone.h>
|
|
|
|
#endif /* !CONFIG_NEED_MULTIPLE_NODES */
|
|
|
|
extern struct pglist_data *first_online_pgdat(void);
|
|
extern struct pglist_data *next_online_pgdat(struct pglist_data *pgdat);
|
|
extern struct zone *next_zone(struct zone *zone);
|
|
|
|
/**
|
|
* for_each_online_pgdat - helper macro to iterate over all online nodes
|
|
* @pgdat - pointer to a pg_data_t variable
|
|
*/
|
|
#define for_each_online_pgdat(pgdat) \
|
|
for (pgdat = first_online_pgdat(); \
|
|
pgdat; \
|
|
pgdat = next_online_pgdat(pgdat))
|
|
/**
|
|
* for_each_zone - helper macro to iterate over all memory zones
|
|
* @zone - pointer to struct zone variable
|
|
*
|
|
* The user only needs to declare the zone variable, for_each_zone
|
|
* fills it in.
|
|
*/
|
|
#define for_each_zone(zone) \
|
|
for (zone = (first_online_pgdat())->node_zones; \
|
|
zone; \
|
|
zone = next_zone(zone))
|
|
|
|
#define for_each_populated_zone(zone) \
|
|
for (zone = (first_online_pgdat())->node_zones; \
|
|
zone; \
|
|
zone = next_zone(zone)) \
|
|
if (!populated_zone(zone)) \
|
|
; /* do nothing */ \
|
|
else
|
|
|
|
static inline struct zone *zonelist_zone(struct zoneref *zoneref)
|
|
{
|
|
return zoneref->zone;
|
|
}
|
|
|
|
static inline int zonelist_zone_idx(struct zoneref *zoneref)
|
|
{
|
|
return zoneref->zone_idx;
|
|
}
|
|
|
|
static inline int zonelist_node_idx(struct zoneref *zoneref)
|
|
{
|
|
#ifdef CONFIG_NUMA
|
|
/* zone_to_nid not available in this context */
|
|
return zoneref->zone->node;
|
|
#else
|
|
return 0;
|
|
#endif /* CONFIG_NUMA */
|
|
}
|
|
|
|
/**
|
|
* next_zones_zonelist - Returns the next zone at or below highest_zoneidx within the allowed nodemask using a cursor within a zonelist as a starting point
|
|
* @z - The cursor used as a starting point for the search
|
|
* @highest_zoneidx - The zone index of the highest zone to return
|
|
* @nodes - An optional nodemask to filter the zonelist with
|
|
* @zone - The first suitable zone found is returned via this parameter
|
|
*
|
|
* This function returns the next zone at or below a given zone index that is
|
|
* within the allowed nodemask using a cursor as the starting point for the
|
|
* search. The zoneref returned is a cursor that represents the current zone
|
|
* being examined. It should be advanced by one before calling
|
|
* next_zones_zonelist again.
|
|
*/
|
|
struct zoneref *next_zones_zonelist(struct zoneref *z,
|
|
enum zone_type highest_zoneidx,
|
|
nodemask_t *nodes,
|
|
struct zone **zone);
|
|
|
|
/**
|
|
* first_zones_zonelist - Returns the first zone at or below highest_zoneidx within the allowed nodemask in a zonelist
|
|
* @zonelist - The zonelist to search for a suitable zone
|
|
* @highest_zoneidx - The zone index of the highest zone to return
|
|
* @nodes - An optional nodemask to filter the zonelist with
|
|
* @zone - The first suitable zone found is returned via this parameter
|
|
*
|
|
* This function returns the first zone at or below a given zone index that is
|
|
* within the allowed nodemask. The zoneref returned is a cursor that can be
|
|
* used to iterate the zonelist with next_zones_zonelist by advancing it by
|
|
* one before calling.
|
|
*/
|
|
static inline struct zoneref *first_zones_zonelist(struct zonelist *zonelist,
|
|
enum zone_type highest_zoneidx,
|
|
nodemask_t *nodes,
|
|
struct zone **zone)
|
|
{
|
|
return next_zones_zonelist(zonelist->_zonerefs, highest_zoneidx, nodes,
|
|
zone);
|
|
}
|
|
|
|
/**
|
|
* for_each_zone_zonelist_nodemask - helper macro to iterate over valid zones in a zonelist at or below a given zone index and within a nodemask
|
|
* @zone - The current zone in the iterator
|
|
* @z - The current pointer within zonelist->zones being iterated
|
|
* @zlist - The zonelist being iterated
|
|
* @highidx - The zone index of the highest zone to return
|
|
* @nodemask - Nodemask allowed by the allocator
|
|
*
|
|
* This iterator iterates though all zones at or below a given zone index and
|
|
* within a given nodemask
|
|
*/
|
|
#define for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, nodemask) \
|
|
for (z = first_zones_zonelist(zlist, highidx, nodemask, &zone); \
|
|
zone; \
|
|
z = next_zones_zonelist(++z, highidx, nodemask, &zone)) \
|
|
|
|
/**
|
|
* for_each_zone_zonelist - helper macro to iterate over valid zones in a zonelist at or below a given zone index
|
|
* @zone - The current zone in the iterator
|
|
* @z - The current pointer within zonelist->zones being iterated
|
|
* @zlist - The zonelist being iterated
|
|
* @highidx - The zone index of the highest zone to return
|
|
*
|
|
* This iterator iterates though all zones at or below a given zone index.
|
|
*/
|
|
#define for_each_zone_zonelist(zone, z, zlist, highidx) \
|
|
for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, NULL)
|
|
|
|
#ifdef CONFIG_SPARSEMEM
|
|
#include <asm/sparsemem.h>
|
|
#endif
|
|
|
|
#if !defined(CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID) && \
|
|
!defined(CONFIG_ARCH_POPULATES_NODE_MAP)
|
|
static inline unsigned long early_pfn_to_nid(unsigned long pfn)
|
|
{
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
#ifdef CONFIG_FLATMEM
|
|
#define pfn_to_nid(pfn) (0)
|
|
#endif
|
|
|
|
#define pfn_to_section_nr(pfn) ((pfn) >> PFN_SECTION_SHIFT)
|
|
#define section_nr_to_pfn(sec) ((sec) << PFN_SECTION_SHIFT)
|
|
|
|
#ifdef CONFIG_SPARSEMEM
|
|
|
|
/*
|
|
* SECTION_SHIFT #bits space required to store a section #
|
|
*
|
|
* PA_SECTION_SHIFT physical address to/from section number
|
|
* PFN_SECTION_SHIFT pfn to/from section number
|
|
*/
|
|
#define SECTIONS_SHIFT (MAX_PHYSMEM_BITS - SECTION_SIZE_BITS)
|
|
|
|
#define PA_SECTION_SHIFT (SECTION_SIZE_BITS)
|
|
#define PFN_SECTION_SHIFT (SECTION_SIZE_BITS - PAGE_SHIFT)
|
|
|
|
#define NR_MEM_SECTIONS (1UL << SECTIONS_SHIFT)
|
|
|
|
#define PAGES_PER_SECTION (1UL << PFN_SECTION_SHIFT)
|
|
#define PAGE_SECTION_MASK (~(PAGES_PER_SECTION-1))
|
|
|
|
#define SECTION_BLOCKFLAGS_BITS \
|
|
((1UL << (PFN_SECTION_SHIFT - pageblock_order)) * NR_PAGEBLOCK_BITS)
|
|
|
|
#if (MAX_ORDER - 1 + PAGE_SHIFT) > SECTION_SIZE_BITS
|
|
#error Allocator MAX_ORDER exceeds SECTION_SIZE
|
|
#endif
|
|
|
|
struct page;
|
|
struct page_cgroup;
|
|
struct mem_section {
|
|
/*
|
|
* This is, logically, a pointer to an array of struct
|
|
* pages. However, it is stored with some other magic.
|
|
* (see sparse.c::sparse_init_one_section())
|
|
*
|
|
* Additionally during early boot we encode node id of
|
|
* the location of the section here to guide allocation.
|
|
* (see sparse.c::memory_present())
|
|
*
|
|
* Making it a UL at least makes someone do a cast
|
|
* before using it wrong.
|
|
*/
|
|
unsigned long section_mem_map;
|
|
|
|
/* See declaration of similar field in struct zone */
|
|
unsigned long *pageblock_flags;
|
|
#ifdef CONFIG_CGROUP_MEM_RES_CTLR
|
|
/*
|
|
* If !SPARSEMEM, pgdat doesn't have page_cgroup pointer. We use
|
|
* section. (see memcontrol.h/page_cgroup.h about this.)
|
|
*/
|
|
struct page_cgroup *page_cgroup;
|
|
unsigned long pad;
|
|
#endif
|
|
};
|
|
|
|
#ifdef CONFIG_SPARSEMEM_EXTREME
|
|
#define SECTIONS_PER_ROOT (PAGE_SIZE / sizeof (struct mem_section))
|
|
#else
|
|
#define SECTIONS_PER_ROOT 1
|
|
#endif
|
|
|
|
#define SECTION_NR_TO_ROOT(sec) ((sec) / SECTIONS_PER_ROOT)
|
|
#define NR_SECTION_ROOTS (NR_MEM_SECTIONS / SECTIONS_PER_ROOT)
|
|
#define SECTION_ROOT_MASK (SECTIONS_PER_ROOT - 1)
|
|
|
|
#ifdef CONFIG_SPARSEMEM_EXTREME
|
|
extern struct mem_section *mem_section[NR_SECTION_ROOTS];
|
|
#else
|
|
extern struct mem_section mem_section[NR_SECTION_ROOTS][SECTIONS_PER_ROOT];
|
|
#endif
|
|
|
|
static inline struct mem_section *__nr_to_section(unsigned long nr)
|
|
{
|
|
if (!mem_section[SECTION_NR_TO_ROOT(nr)])
|
|
return NULL;
|
|
return &mem_section[SECTION_NR_TO_ROOT(nr)][nr & SECTION_ROOT_MASK];
|
|
}
|
|
extern int __section_nr(struct mem_section* ms);
|
|
extern unsigned long usemap_size(void);
|
|
|
|
/*
|
|
* We use the lower bits of the mem_map pointer to store
|
|
* a little bit of information. There should be at least
|
|
* 3 bits here due to 32-bit alignment.
|
|
*/
|
|
#define SECTION_MARKED_PRESENT (1UL<<0)
|
|
#define SECTION_HAS_MEM_MAP (1UL<<1)
|
|
#define SECTION_MAP_LAST_BIT (1UL<<2)
|
|
#define SECTION_MAP_MASK (~(SECTION_MAP_LAST_BIT-1))
|
|
#define SECTION_NID_SHIFT 2
|
|
|
|
static inline struct page *__section_mem_map_addr(struct mem_section *section)
|
|
{
|
|
unsigned long map = section->section_mem_map;
|
|
map &= SECTION_MAP_MASK;
|
|
return (struct page *)map;
|
|
}
|
|
|
|
static inline int present_section(struct mem_section *section)
|
|
{
|
|
return (section && (section->section_mem_map & SECTION_MARKED_PRESENT));
|
|
}
|
|
|
|
static inline int present_section_nr(unsigned long nr)
|
|
{
|
|
return present_section(__nr_to_section(nr));
|
|
}
|
|
|
|
static inline int valid_section(struct mem_section *section)
|
|
{
|
|
return (section && (section->section_mem_map & SECTION_HAS_MEM_MAP));
|
|
}
|
|
|
|
static inline int valid_section_nr(unsigned long nr)
|
|
{
|
|
return valid_section(__nr_to_section(nr));
|
|
}
|
|
|
|
static inline struct mem_section *__pfn_to_section(unsigned long pfn)
|
|
{
|
|
return __nr_to_section(pfn_to_section_nr(pfn));
|
|
}
|
|
|
|
static inline int pfn_valid(unsigned long pfn)
|
|
{
|
|
if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS)
|
|
return 0;
|
|
return valid_section(__nr_to_section(pfn_to_section_nr(pfn)));
|
|
}
|
|
|
|
static inline int pfn_present(unsigned long pfn)
|
|
{
|
|
if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS)
|
|
return 0;
|
|
return present_section(__nr_to_section(pfn_to_section_nr(pfn)));
|
|
}
|
|
|
|
/*
|
|
* These are _only_ used during initialisation, therefore they
|
|
* can use __initdata ... They could have names to indicate
|
|
* this restriction.
|
|
*/
|
|
#ifdef CONFIG_NUMA
|
|
#define pfn_to_nid(pfn) \
|
|
({ \
|
|
unsigned long __pfn_to_nid_pfn = (pfn); \
|
|
page_to_nid(pfn_to_page(__pfn_to_nid_pfn)); \
|
|
})
|
|
#else
|
|
#define pfn_to_nid(pfn) (0)
|
|
#endif
|
|
|
|
#define early_pfn_valid(pfn) pfn_valid(pfn)
|
|
void sparse_init(void);
|
|
#else
|
|
#define sparse_init() do {} while (0)
|
|
#define sparse_index_init(_sec, _nid) do {} while (0)
|
|
#endif /* CONFIG_SPARSEMEM */
|
|
|
|
#ifdef CONFIG_NODES_SPAN_OTHER_NODES
|
|
bool early_pfn_in_nid(unsigned long pfn, int nid);
|
|
#else
|
|
#define early_pfn_in_nid(pfn, nid) (1)
|
|
#endif
|
|
|
|
#ifndef early_pfn_valid
|
|
#define early_pfn_valid(pfn) (1)
|
|
#endif
|
|
|
|
void memory_present(int nid, unsigned long start, unsigned long end);
|
|
unsigned long __init node_memmap_size_bytes(int, unsigned long, unsigned long);
|
|
|
|
/*
|
|
* If it is possible to have holes within a MAX_ORDER_NR_PAGES, then we
|
|
* need to check pfn validility within that MAX_ORDER_NR_PAGES block.
|
|
* pfn_valid_within() should be used in this case; we optimise this away
|
|
* when we have no holes within a MAX_ORDER_NR_PAGES block.
|
|
*/
|
|
#ifdef CONFIG_HOLES_IN_ZONE
|
|
#define pfn_valid_within(pfn) pfn_valid(pfn)
|
|
#else
|
|
#define pfn_valid_within(pfn) (1)
|
|
#endif
|
|
|
|
#ifdef CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
|
|
/*
|
|
* pfn_valid() is meant to be able to tell if a given PFN has valid memmap
|
|
* associated with it or not. In FLATMEM, it is expected that holes always
|
|
* have valid memmap as long as there is valid PFNs either side of the hole.
|
|
* In SPARSEMEM, it is assumed that a valid section has a memmap for the
|
|
* entire section.
|
|
*
|
|
* However, an ARM, and maybe other embedded architectures in the future
|
|
* free memmap backing holes to save memory on the assumption the memmap is
|
|
* never used. The page_zone linkages are then broken even though pfn_valid()
|
|
* returns true. A walker of the full memmap must then do this additional
|
|
* check to ensure the memmap they are looking at is sane by making sure
|
|
* the zone and PFN linkages are still valid. This is expensive, but walkers
|
|
* of the full memmap are extremely rare.
|
|
*/
|
|
int memmap_valid_within(unsigned long pfn,
|
|
struct page *page, struct zone *zone);
|
|
#else
|
|
static inline int memmap_valid_within(unsigned long pfn,
|
|
struct page *page, struct zone *zone)
|
|
{
|
|
return 1;
|
|
}
|
|
#endif /* CONFIG_ARCH_HAS_HOLES_MEMORYMODEL */
|
|
|
|
#endif /* !__GENERATING_BOUNDS.H */
|
|
#endif /* !__ASSEMBLY__ */
|
|
#endif /* _LINUX_MMZONE_H */
|