![Linus Torvalds](/assets/img/avatar_default.png)
The per-zone waitqueues exist because of a scalability issue with the page waitqueues on some NUMA machines, but it turns out that they hurt normal loads, and now with the vmalloced stacks they also end up breaking gfs2 that uses a bit_wait on a stack object: wait_on_bit(&gh->gh_iflags, HIF_WAIT, TASK_UNINTERRUPTIBLE) where 'gh' can be a reference to the local variable 'mount_gh' on the stack of fill_super(). The reason the per-zone hash table breaks for this case is that there is no "zone" for virtual allocations, and trying to look up the physical page to get at it will fail (with a BUG_ON()). It turns out that I actually complained to the mm people about the per-zone hash table for another reason just a month ago: the zone lookup also hurts the regular use of "unlock_page()" a lot, because the zone lookup ends up forcing several unnecessary cache misses and generates horrible code. As part of that earlier discussion, we had a much better solution for the NUMA scalability issue - by just making the page lock have a separate contention bit, the waitqueue doesn't even have to be looked at for the normal case. Peter Zijlstra already has a patch for that, but let's see if anybody even notices. In the meantime, let's fix the actual gfs2 breakage by simplifying the bitlock waitqueues and removing the per-zone issue. Reported-by: Andreas Gruenbacher <agruenba@redhat.com> Tested-by: Bob Peterson <rpeterso@redhat.com> Acked-by: Mel Gorman <mgorman@techsingularity.net> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Steven Whitehouse <swhiteho@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1269 lines
38 KiB
C
1269 lines
38 KiB
C
#ifndef _LINUX_MMZONE_H
|
|
#define _LINUX_MMZONE_H
|
|
|
|
#ifndef __ASSEMBLY__
|
|
#ifndef __GENERATING_BOUNDS_H
|
|
|
|
#include <linux/spinlock.h>
|
|
#include <linux/list.h>
|
|
#include <linux/wait.h>
|
|
#include <linux/bitops.h>
|
|
#include <linux/cache.h>
|
|
#include <linux/threads.h>
|
|
#include <linux/numa.h>
|
|
#include <linux/init.h>
|
|
#include <linux/seqlock.h>
|
|
#include <linux/nodemask.h>
|
|
#include <linux/pageblock-flags.h>
|
|
#include <linux/page-flags-layout.h>
|
|
#include <linux/atomic.h>
|
|
#include <asm/page.h>
|
|
|
|
/* Free memory management - zoned buddy allocator. */
|
|
#ifndef CONFIG_FORCE_MAX_ZONEORDER
|
|
#define MAX_ORDER 11
|
|
#else
|
|
#define MAX_ORDER CONFIG_FORCE_MAX_ZONEORDER
|
|
#endif
|
|
#define MAX_ORDER_NR_PAGES (1 << (MAX_ORDER - 1))
|
|
|
|
/*
|
|
* PAGE_ALLOC_COSTLY_ORDER is the order at which allocations are deemed
|
|
* costly to service. That is between allocation orders which should
|
|
* coalesce naturally under reasonable reclaim pressure and those which
|
|
* will not.
|
|
*/
|
|
#define PAGE_ALLOC_COSTLY_ORDER 3
|
|
|
|
enum {
|
|
MIGRATE_UNMOVABLE,
|
|
MIGRATE_MOVABLE,
|
|
MIGRATE_RECLAIMABLE,
|
|
MIGRATE_PCPTYPES, /* the number of types on the pcp lists */
|
|
MIGRATE_HIGHATOMIC = MIGRATE_PCPTYPES,
|
|
#ifdef CONFIG_CMA
|
|
/*
|
|
* MIGRATE_CMA migration type is designed to mimic the way
|
|
* ZONE_MOVABLE works. Only movable pages can be allocated
|
|
* from MIGRATE_CMA pageblocks and page allocator never
|
|
* implicitly change migration type of MIGRATE_CMA pageblock.
|
|
*
|
|
* The way to use it is to change migratetype of a range of
|
|
* pageblocks to MIGRATE_CMA which can be done by
|
|
* __free_pageblock_cma() function. What is important though
|
|
* is that a range of pageblocks must be aligned to
|
|
* MAX_ORDER_NR_PAGES should biggest page be bigger then
|
|
* a single pageblock.
|
|
*/
|
|
MIGRATE_CMA,
|
|
#endif
|
|
#ifdef CONFIG_MEMORY_ISOLATION
|
|
MIGRATE_ISOLATE, /* can't allocate from here */
|
|
#endif
|
|
MIGRATE_TYPES
|
|
};
|
|
|
|
/* In mm/page_alloc.c; keep in sync also with show_migration_types() there */
|
|
extern char * const migratetype_names[MIGRATE_TYPES];
|
|
|
|
#ifdef CONFIG_CMA
|
|
# define is_migrate_cma(migratetype) unlikely((migratetype) == MIGRATE_CMA)
|
|
# define is_migrate_cma_page(_page) (get_pageblock_migratetype(_page) == MIGRATE_CMA)
|
|
#else
|
|
# define is_migrate_cma(migratetype) false
|
|
# define is_migrate_cma_page(_page) false
|
|
#endif
|
|
|
|
#define for_each_migratetype_order(order, type) \
|
|
for (order = 0; order < MAX_ORDER; order++) \
|
|
for (type = 0; type < MIGRATE_TYPES; type++)
|
|
|
|
extern int page_group_by_mobility_disabled;
|
|
|
|
#define NR_MIGRATETYPE_BITS (PB_migrate_end - PB_migrate + 1)
|
|
#define MIGRATETYPE_MASK ((1UL << NR_MIGRATETYPE_BITS) - 1)
|
|
|
|
#define get_pageblock_migratetype(page) \
|
|
get_pfnblock_flags_mask(page, page_to_pfn(page), \
|
|
PB_migrate_end, MIGRATETYPE_MASK)
|
|
|
|
struct free_area {
|
|
struct list_head free_list[MIGRATE_TYPES];
|
|
unsigned long nr_free;
|
|
};
|
|
|
|
struct pglist_data;
|
|
|
|
/*
|
|
* zone->lock and the zone lru_lock are two of the hottest locks in the kernel.
|
|
* So add a wild amount of padding here to ensure that they fall into separate
|
|
* cachelines. There are very few zone structures in the machine, so space
|
|
* consumption is not a concern here.
|
|
*/
|
|
#if defined(CONFIG_SMP)
|
|
struct zone_padding {
|
|
char x[0];
|
|
} ____cacheline_internodealigned_in_smp;
|
|
#define ZONE_PADDING(name) struct zone_padding name;
|
|
#else
|
|
#define ZONE_PADDING(name)
|
|
#endif
|
|
|
|
enum zone_stat_item {
|
|
/* First 128 byte cacheline (assuming 64 bit words) */
|
|
NR_FREE_PAGES,
|
|
NR_ZONE_LRU_BASE, /* Used only for compaction and reclaim retry */
|
|
NR_ZONE_INACTIVE_ANON = NR_ZONE_LRU_BASE,
|
|
NR_ZONE_ACTIVE_ANON,
|
|
NR_ZONE_INACTIVE_FILE,
|
|
NR_ZONE_ACTIVE_FILE,
|
|
NR_ZONE_UNEVICTABLE,
|
|
NR_ZONE_WRITE_PENDING, /* Count of dirty, writeback and unstable pages */
|
|
NR_MLOCK, /* mlock()ed pages found and moved off LRU */
|
|
NR_SLAB_RECLAIMABLE,
|
|
NR_SLAB_UNRECLAIMABLE,
|
|
NR_PAGETABLE, /* used for pagetables */
|
|
NR_KERNEL_STACK_KB, /* measured in KiB */
|
|
/* Second 128 byte cacheline */
|
|
NR_BOUNCE,
|
|
#if IS_ENABLED(CONFIG_ZSMALLOC)
|
|
NR_ZSPAGES, /* allocated in zsmalloc */
|
|
#endif
|
|
#ifdef CONFIG_NUMA
|
|
NUMA_HIT, /* allocated in intended node */
|
|
NUMA_MISS, /* allocated in non intended node */
|
|
NUMA_FOREIGN, /* was intended here, hit elsewhere */
|
|
NUMA_INTERLEAVE_HIT, /* interleaver preferred this zone */
|
|
NUMA_LOCAL, /* allocation from local node */
|
|
NUMA_OTHER, /* allocation from other node */
|
|
#endif
|
|
NR_FREE_CMA_PAGES,
|
|
NR_VM_ZONE_STAT_ITEMS };
|
|
|
|
enum node_stat_item {
|
|
NR_LRU_BASE,
|
|
NR_INACTIVE_ANON = NR_LRU_BASE, /* must match order of LRU_[IN]ACTIVE */
|
|
NR_ACTIVE_ANON, /* " " " " " */
|
|
NR_INACTIVE_FILE, /* " " " " " */
|
|
NR_ACTIVE_FILE, /* " " " " " */
|
|
NR_UNEVICTABLE, /* " " " " " */
|
|
NR_ISOLATED_ANON, /* Temporary isolated pages from anon lru */
|
|
NR_ISOLATED_FILE, /* Temporary isolated pages from file lru */
|
|
NR_PAGES_SCANNED, /* pages scanned since last reclaim */
|
|
WORKINGSET_REFAULT,
|
|
WORKINGSET_ACTIVATE,
|
|
WORKINGSET_NODERECLAIM,
|
|
NR_ANON_MAPPED, /* Mapped anonymous pages */
|
|
NR_FILE_MAPPED, /* pagecache pages mapped into pagetables.
|
|
only modified from process context */
|
|
NR_FILE_PAGES,
|
|
NR_FILE_DIRTY,
|
|
NR_WRITEBACK,
|
|
NR_WRITEBACK_TEMP, /* Writeback using temporary buffers */
|
|
NR_SHMEM, /* shmem pages (included tmpfs/GEM pages) */
|
|
NR_SHMEM_THPS,
|
|
NR_SHMEM_PMDMAPPED,
|
|
NR_ANON_THPS,
|
|
NR_UNSTABLE_NFS, /* NFS unstable pages */
|
|
NR_VMSCAN_WRITE,
|
|
NR_VMSCAN_IMMEDIATE, /* Prioritise for reclaim when writeback ends */
|
|
NR_DIRTIED, /* page dirtyings since bootup */
|
|
NR_WRITTEN, /* page writings since bootup */
|
|
NR_VM_NODE_STAT_ITEMS
|
|
};
|
|
|
|
/*
|
|
* We do arithmetic on the LRU lists in various places in the code,
|
|
* so it is important to keep the active lists LRU_ACTIVE higher in
|
|
* the array than the corresponding inactive lists, and to keep
|
|
* the *_FILE lists LRU_FILE higher than the corresponding _ANON lists.
|
|
*
|
|
* This has to be kept in sync with the statistics in zone_stat_item
|
|
* above and the descriptions in vmstat_text in mm/vmstat.c
|
|
*/
|
|
#define LRU_BASE 0
|
|
#define LRU_ACTIVE 1
|
|
#define LRU_FILE 2
|
|
|
|
enum lru_list {
|
|
LRU_INACTIVE_ANON = LRU_BASE,
|
|
LRU_ACTIVE_ANON = LRU_BASE + LRU_ACTIVE,
|
|
LRU_INACTIVE_FILE = LRU_BASE + LRU_FILE,
|
|
LRU_ACTIVE_FILE = LRU_BASE + LRU_FILE + LRU_ACTIVE,
|
|
LRU_UNEVICTABLE,
|
|
NR_LRU_LISTS
|
|
};
|
|
|
|
#define for_each_lru(lru) for (lru = 0; lru < NR_LRU_LISTS; lru++)
|
|
|
|
#define for_each_evictable_lru(lru) for (lru = 0; lru <= LRU_ACTIVE_FILE; lru++)
|
|
|
|
static inline int is_file_lru(enum lru_list lru)
|
|
{
|
|
return (lru == LRU_INACTIVE_FILE || lru == LRU_ACTIVE_FILE);
|
|
}
|
|
|
|
static inline int is_active_lru(enum lru_list lru)
|
|
{
|
|
return (lru == LRU_ACTIVE_ANON || lru == LRU_ACTIVE_FILE);
|
|
}
|
|
|
|
struct zone_reclaim_stat {
|
|
/*
|
|
* The pageout code in vmscan.c keeps track of how many of the
|
|
* mem/swap backed and file backed pages are referenced.
|
|
* The higher the rotated/scanned ratio, the more valuable
|
|
* that cache is.
|
|
*
|
|
* The anon LRU stats live in [0], file LRU stats in [1]
|
|
*/
|
|
unsigned long recent_rotated[2];
|
|
unsigned long recent_scanned[2];
|
|
};
|
|
|
|
struct lruvec {
|
|
struct list_head lists[NR_LRU_LISTS];
|
|
struct zone_reclaim_stat reclaim_stat;
|
|
/* Evictions & activations on the inactive file list */
|
|
atomic_long_t inactive_age;
|
|
#ifdef CONFIG_MEMCG
|
|
struct pglist_data *pgdat;
|
|
#endif
|
|
};
|
|
|
|
/* Mask used at gathering information at once (see memcontrol.c) */
|
|
#define LRU_ALL_FILE (BIT(LRU_INACTIVE_FILE) | BIT(LRU_ACTIVE_FILE))
|
|
#define LRU_ALL_ANON (BIT(LRU_INACTIVE_ANON) | BIT(LRU_ACTIVE_ANON))
|
|
#define LRU_ALL ((1 << NR_LRU_LISTS) - 1)
|
|
|
|
/* Isolate clean file */
|
|
#define ISOLATE_CLEAN ((__force isolate_mode_t)0x1)
|
|
/* Isolate unmapped file */
|
|
#define ISOLATE_UNMAPPED ((__force isolate_mode_t)0x2)
|
|
/* Isolate for asynchronous migration */
|
|
#define ISOLATE_ASYNC_MIGRATE ((__force isolate_mode_t)0x4)
|
|
/* Isolate unevictable pages */
|
|
#define ISOLATE_UNEVICTABLE ((__force isolate_mode_t)0x8)
|
|
|
|
/* LRU Isolation modes. */
|
|
typedef unsigned __bitwise__ isolate_mode_t;
|
|
|
|
enum zone_watermarks {
|
|
WMARK_MIN,
|
|
WMARK_LOW,
|
|
WMARK_HIGH,
|
|
NR_WMARK
|
|
};
|
|
|
|
#define min_wmark_pages(z) (z->watermark[WMARK_MIN])
|
|
#define low_wmark_pages(z) (z->watermark[WMARK_LOW])
|
|
#define high_wmark_pages(z) (z->watermark[WMARK_HIGH])
|
|
|
|
struct per_cpu_pages {
|
|
int count; /* number of pages in the list */
|
|
int high; /* high watermark, emptying needed */
|
|
int batch; /* chunk size for buddy add/remove */
|
|
|
|
/* Lists of pages, one per migrate type stored on the pcp-lists */
|
|
struct list_head lists[MIGRATE_PCPTYPES];
|
|
};
|
|
|
|
struct per_cpu_pageset {
|
|
struct per_cpu_pages pcp;
|
|
#ifdef CONFIG_NUMA
|
|
s8 expire;
|
|
#endif
|
|
#ifdef CONFIG_SMP
|
|
s8 stat_threshold;
|
|
s8 vm_stat_diff[NR_VM_ZONE_STAT_ITEMS];
|
|
#endif
|
|
};
|
|
|
|
struct per_cpu_nodestat {
|
|
s8 stat_threshold;
|
|
s8 vm_node_stat_diff[NR_VM_NODE_STAT_ITEMS];
|
|
};
|
|
|
|
#endif /* !__GENERATING_BOUNDS.H */
|
|
|
|
enum zone_type {
|
|
#ifdef CONFIG_ZONE_DMA
|
|
/*
|
|
* ZONE_DMA is used when there are devices that are not able
|
|
* to do DMA to all of addressable memory (ZONE_NORMAL). Then we
|
|
* carve out the portion of memory that is needed for these devices.
|
|
* The range is arch specific.
|
|
*
|
|
* Some examples
|
|
*
|
|
* Architecture Limit
|
|
* ---------------------------
|
|
* parisc, ia64, sparc <4G
|
|
* s390 <2G
|
|
* arm Various
|
|
* alpha Unlimited or 0-16MB.
|
|
*
|
|
* i386, x86_64 and multiple other arches
|
|
* <16M.
|
|
*/
|
|
ZONE_DMA,
|
|
#endif
|
|
#ifdef CONFIG_ZONE_DMA32
|
|
/*
|
|
* x86_64 needs two ZONE_DMAs because it supports devices that are
|
|
* only able to do DMA to the lower 16M but also 32 bit devices that
|
|
* can only do DMA areas below 4G.
|
|
*/
|
|
ZONE_DMA32,
|
|
#endif
|
|
/*
|
|
* Normal addressable memory is in ZONE_NORMAL. DMA operations can be
|
|
* performed on pages in ZONE_NORMAL if the DMA devices support
|
|
* transfers to all addressable memory.
|
|
*/
|
|
ZONE_NORMAL,
|
|
#ifdef CONFIG_HIGHMEM
|
|
/*
|
|
* A memory area that is only addressable by the kernel through
|
|
* mapping portions into its own address space. This is for example
|
|
* used by i386 to allow the kernel to address the memory beyond
|
|
* 900MB. The kernel will set up special mappings (page
|
|
* table entries on i386) for each page that the kernel needs to
|
|
* access.
|
|
*/
|
|
ZONE_HIGHMEM,
|
|
#endif
|
|
ZONE_MOVABLE,
|
|
#ifdef CONFIG_ZONE_DEVICE
|
|
ZONE_DEVICE,
|
|
#endif
|
|
__MAX_NR_ZONES
|
|
|
|
};
|
|
|
|
#ifndef __GENERATING_BOUNDS_H
|
|
|
|
struct zone {
|
|
/* Read-mostly fields */
|
|
|
|
/* zone watermarks, access with *_wmark_pages(zone) macros */
|
|
unsigned long watermark[NR_WMARK];
|
|
|
|
unsigned long nr_reserved_highatomic;
|
|
|
|
/*
|
|
* We don't know if the memory that we're going to allocate will be
|
|
* freeable or/and it will be released eventually, so to avoid totally
|
|
* wasting several GB of ram we must reserve some of the lower zone
|
|
* memory (otherwise we risk to run OOM on the lower zones despite
|
|
* there being tons of freeable ram on the higher zones). This array is
|
|
* recalculated at runtime if the sysctl_lowmem_reserve_ratio sysctl
|
|
* changes.
|
|
*/
|
|
long lowmem_reserve[MAX_NR_ZONES];
|
|
|
|
#ifdef CONFIG_NUMA
|
|
int node;
|
|
#endif
|
|
struct pglist_data *zone_pgdat;
|
|
struct per_cpu_pageset __percpu *pageset;
|
|
|
|
#ifndef CONFIG_SPARSEMEM
|
|
/*
|
|
* Flags for a pageblock_nr_pages block. See pageblock-flags.h.
|
|
* In SPARSEMEM, this map is stored in struct mem_section
|
|
*/
|
|
unsigned long *pageblock_flags;
|
|
#endif /* CONFIG_SPARSEMEM */
|
|
|
|
/* zone_start_pfn == zone_start_paddr >> PAGE_SHIFT */
|
|
unsigned long zone_start_pfn;
|
|
|
|
/*
|
|
* spanned_pages is the total pages spanned by the zone, including
|
|
* holes, which is calculated as:
|
|
* spanned_pages = zone_end_pfn - zone_start_pfn;
|
|
*
|
|
* present_pages is physical pages existing within the zone, which
|
|
* is calculated as:
|
|
* present_pages = spanned_pages - absent_pages(pages in holes);
|
|
*
|
|
* managed_pages is present pages managed by the buddy system, which
|
|
* is calculated as (reserved_pages includes pages allocated by the
|
|
* bootmem allocator):
|
|
* managed_pages = present_pages - reserved_pages;
|
|
*
|
|
* So present_pages may be used by memory hotplug or memory power
|
|
* management logic to figure out unmanaged pages by checking
|
|
* (present_pages - managed_pages). And managed_pages should be used
|
|
* by page allocator and vm scanner to calculate all kinds of watermarks
|
|
* and thresholds.
|
|
*
|
|
* Locking rules:
|
|
*
|
|
* zone_start_pfn and spanned_pages are protected by span_seqlock.
|
|
* It is a seqlock because it has to be read outside of zone->lock,
|
|
* and it is done in the main allocator path. But, it is written
|
|
* quite infrequently.
|
|
*
|
|
* The span_seq lock is declared along with zone->lock because it is
|
|
* frequently read in proximity to zone->lock. It's good to
|
|
* give them a chance of being in the same cacheline.
|
|
*
|
|
* Write access to present_pages at runtime should be protected by
|
|
* mem_hotplug_begin/end(). Any reader who can't tolerant drift of
|
|
* present_pages should get_online_mems() to get a stable value.
|
|
*
|
|
* Read access to managed_pages should be safe because it's unsigned
|
|
* long. Write access to zone->managed_pages and totalram_pages are
|
|
* protected by managed_page_count_lock at runtime. Idealy only
|
|
* adjust_managed_page_count() should be used instead of directly
|
|
* touching zone->managed_pages and totalram_pages.
|
|
*/
|
|
unsigned long managed_pages;
|
|
unsigned long spanned_pages;
|
|
unsigned long present_pages;
|
|
|
|
const char *name;
|
|
|
|
#ifdef CONFIG_MEMORY_ISOLATION
|
|
/*
|
|
* Number of isolated pageblock. It is used to solve incorrect
|
|
* freepage counting problem due to racy retrieving migratetype
|
|
* of pageblock. Protected by zone->lock.
|
|
*/
|
|
unsigned long nr_isolate_pageblock;
|
|
#endif
|
|
|
|
#ifdef CONFIG_MEMORY_HOTPLUG
|
|
/* see spanned/present_pages for more description */
|
|
seqlock_t span_seqlock;
|
|
#endif
|
|
|
|
int initialized;
|
|
|
|
/* Write-intensive fields used from the page allocator */
|
|
ZONE_PADDING(_pad1_)
|
|
|
|
/* free areas of different sizes */
|
|
struct free_area free_area[MAX_ORDER];
|
|
|
|
/* zone flags, see below */
|
|
unsigned long flags;
|
|
|
|
/* Primarily protects free_area */
|
|
spinlock_t lock;
|
|
|
|
/* Write-intensive fields used by compaction and vmstats. */
|
|
ZONE_PADDING(_pad2_)
|
|
|
|
/*
|
|
* When free pages are below this point, additional steps are taken
|
|
* when reading the number of free pages to avoid per-cpu counter
|
|
* drift allowing watermarks to be breached
|
|
*/
|
|
unsigned long percpu_drift_mark;
|
|
|
|
#if defined CONFIG_COMPACTION || defined CONFIG_CMA
|
|
/* pfn where compaction free scanner should start */
|
|
unsigned long compact_cached_free_pfn;
|
|
/* pfn where async and sync compaction migration scanner should start */
|
|
unsigned long compact_cached_migrate_pfn[2];
|
|
#endif
|
|
|
|
#ifdef CONFIG_COMPACTION
|
|
/*
|
|
* On compaction failure, 1<<compact_defer_shift compactions
|
|
* are skipped before trying again. The number attempted since
|
|
* last failure is tracked with compact_considered.
|
|
*/
|
|
unsigned int compact_considered;
|
|
unsigned int compact_defer_shift;
|
|
int compact_order_failed;
|
|
#endif
|
|
|
|
#if defined CONFIG_COMPACTION || defined CONFIG_CMA
|
|
/* Set to true when the PG_migrate_skip bits should be cleared */
|
|
bool compact_blockskip_flush;
|
|
#endif
|
|
|
|
bool contiguous;
|
|
|
|
ZONE_PADDING(_pad3_)
|
|
/* Zone statistics */
|
|
atomic_long_t vm_stat[NR_VM_ZONE_STAT_ITEMS];
|
|
} ____cacheline_internodealigned_in_smp;
|
|
|
|
enum pgdat_flags {
|
|
PGDAT_CONGESTED, /* pgdat has many dirty pages backed by
|
|
* a congested BDI
|
|
*/
|
|
PGDAT_DIRTY, /* reclaim scanning has recently found
|
|
* many dirty file pages at the tail
|
|
* of the LRU.
|
|
*/
|
|
PGDAT_WRITEBACK, /* reclaim scanning has recently found
|
|
* many pages under writeback
|
|
*/
|
|
PGDAT_RECLAIM_LOCKED, /* prevents concurrent reclaim */
|
|
};
|
|
|
|
static inline unsigned long zone_end_pfn(const struct zone *zone)
|
|
{
|
|
return zone->zone_start_pfn + zone->spanned_pages;
|
|
}
|
|
|
|
static inline bool zone_spans_pfn(const struct zone *zone, unsigned long pfn)
|
|
{
|
|
return zone->zone_start_pfn <= pfn && pfn < zone_end_pfn(zone);
|
|
}
|
|
|
|
static inline bool zone_is_initialized(struct zone *zone)
|
|
{
|
|
return zone->initialized;
|
|
}
|
|
|
|
static inline bool zone_is_empty(struct zone *zone)
|
|
{
|
|
return zone->spanned_pages == 0;
|
|
}
|
|
|
|
/*
|
|
* The "priority" of VM scanning is how much of the queues we will scan in one
|
|
* go. A value of 12 for DEF_PRIORITY implies that we will scan 1/4096th of the
|
|
* queues ("queue_length >> 12") during an aging round.
|
|
*/
|
|
#define DEF_PRIORITY 12
|
|
|
|
/* Maximum number of zones on a zonelist */
|
|
#define MAX_ZONES_PER_ZONELIST (MAX_NUMNODES * MAX_NR_ZONES)
|
|
|
|
enum {
|
|
ZONELIST_FALLBACK, /* zonelist with fallback */
|
|
#ifdef CONFIG_NUMA
|
|
/*
|
|
* The NUMA zonelists are doubled because we need zonelists that
|
|
* restrict the allocations to a single node for __GFP_THISNODE.
|
|
*/
|
|
ZONELIST_NOFALLBACK, /* zonelist without fallback (__GFP_THISNODE) */
|
|
#endif
|
|
MAX_ZONELISTS
|
|
};
|
|
|
|
/*
|
|
* 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.
|
|
*
|
|
* 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 zoneref _zonerefs[MAX_ZONES_PER_ZONELIST + 1];
|
|
};
|
|
|
|
#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_PAGE_EXTENSION
|
|
struct page_ext *node_page_ext;
|
|
#endif
|
|
#endif
|
|
#ifndef CONFIG_NO_BOOTMEM
|
|
struct bootmem_data *bdata;
|
|
#endif
|
|
#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.
|
|
*
|
|
* pgdat_resize_lock() and pgdat_resize_unlock() are provided to
|
|
* manipulate node_size_lock without checking for CONFIG_MEMORY_HOTPLUG.
|
|
*
|
|
* Nests above zone->lock and zone->span_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;
|
|
wait_queue_head_t pfmemalloc_wait;
|
|
struct task_struct *kswapd; /* Protected by
|
|
mem_hotplug_begin/end() */
|
|
int kswapd_order;
|
|
enum zone_type kswapd_classzone_idx;
|
|
|
|
#ifdef CONFIG_COMPACTION
|
|
int kcompactd_max_order;
|
|
enum zone_type kcompactd_classzone_idx;
|
|
wait_queue_head_t kcompactd_wait;
|
|
struct task_struct *kcompactd;
|
|
#endif
|
|
#ifdef CONFIG_NUMA_BALANCING
|
|
/* Lock serializing the migrate rate limiting window */
|
|
spinlock_t numabalancing_migrate_lock;
|
|
|
|
/* Rate limiting time interval */
|
|
unsigned long numabalancing_migrate_next_window;
|
|
|
|
/* Number of pages migrated during the rate limiting time interval */
|
|
unsigned long numabalancing_migrate_nr_pages;
|
|
#endif
|
|
/*
|
|
* This is a per-node reserve of pages that are not available
|
|
* to userspace allocations.
|
|
*/
|
|
unsigned long totalreserve_pages;
|
|
|
|
#ifdef CONFIG_NUMA
|
|
/*
|
|
* zone reclaim becomes active if more unmapped pages exist.
|
|
*/
|
|
unsigned long min_unmapped_pages;
|
|
unsigned long min_slab_pages;
|
|
#endif /* CONFIG_NUMA */
|
|
|
|
/* Write-intensive fields used by page reclaim */
|
|
ZONE_PADDING(_pad1_)
|
|
spinlock_t lru_lock;
|
|
|
|
#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
|
|
/*
|
|
* If memory initialisation on large machines is deferred then this
|
|
* is the first PFN that needs to be initialised.
|
|
*/
|
|
unsigned long first_deferred_pfn;
|
|
#endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */
|
|
|
|
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
|
|
spinlock_t split_queue_lock;
|
|
struct list_head split_queue;
|
|
unsigned long split_queue_len;
|
|
#endif
|
|
|
|
/* Fields commonly accessed by the page reclaim scanner */
|
|
struct lruvec lruvec;
|
|
|
|
/*
|
|
* The target ratio of ACTIVE_ANON to INACTIVE_ANON pages on
|
|
* this node's LRU. Maintained by the pageout code.
|
|
*/
|
|
unsigned int inactive_ratio;
|
|
|
|
unsigned long flags;
|
|
|
|
ZONE_PADDING(_pad2_)
|
|
|
|
/* Per-node vmstats */
|
|
struct per_cpu_nodestat __percpu *per_cpu_nodestats;
|
|
atomic_long_t vm_stat[NR_VM_NODE_STAT_ITEMS];
|
|
} 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))
|
|
|
|
#define node_start_pfn(nid) (NODE_DATA(nid)->node_start_pfn)
|
|
#define node_end_pfn(nid) pgdat_end_pfn(NODE_DATA(nid))
|
|
static inline spinlock_t *zone_lru_lock(struct zone *zone)
|
|
{
|
|
return &zone->zone_pgdat->lru_lock;
|
|
}
|
|
|
|
static inline struct lruvec *node_lruvec(struct pglist_data *pgdat)
|
|
{
|
|
return &pgdat->lruvec;
|
|
}
|
|
|
|
static inline unsigned long pgdat_end_pfn(pg_data_t *pgdat)
|
|
{
|
|
return pgdat->node_start_pfn + pgdat->node_spanned_pages;
|
|
}
|
|
|
|
static inline bool pgdat_is_empty(pg_data_t *pgdat)
|
|
{
|
|
return !pgdat->node_start_pfn && !pgdat->node_spanned_pages;
|
|
}
|
|
|
|
static inline int zone_id(const struct zone *zone)
|
|
{
|
|
struct pglist_data *pgdat = zone->zone_pgdat;
|
|
|
|
return zone - pgdat->node_zones;
|
|
}
|
|
|
|
#ifdef CONFIG_ZONE_DEVICE
|
|
static inline bool is_dev_zone(const struct zone *zone)
|
|
{
|
|
return zone_id(zone) == ZONE_DEVICE;
|
|
}
|
|
#else
|
|
static inline bool is_dev_zone(const struct zone *zone)
|
|
{
|
|
return false;
|
|
}
|
|
#endif
|
|
|
|
#include <linux/memory_hotplug.h>
|
|
|
|
extern struct mutex zonelists_mutex;
|
|
void build_all_zonelists(pg_data_t *pgdat, struct zone *zone);
|
|
void wakeup_kswapd(struct zone *zone, int order, enum zone_type classzone_idx);
|
|
bool __zone_watermark_ok(struct zone *z, unsigned int order, unsigned long mark,
|
|
int classzone_idx, unsigned int alloc_flags,
|
|
long free_pages);
|
|
bool zone_watermark_ok(struct zone *z, unsigned int order,
|
|
unsigned long mark, int classzone_idx,
|
|
unsigned int alloc_flags);
|
|
bool zone_watermark_ok_safe(struct zone *z, unsigned int order,
|
|
unsigned long mark, int classzone_idx);
|
|
enum memmap_context {
|
|
MEMMAP_EARLY,
|
|
MEMMAP_HOTPLUG,
|
|
};
|
|
extern int init_currently_empty_zone(struct zone *zone, unsigned long start_pfn,
|
|
unsigned long size);
|
|
|
|
extern void lruvec_init(struct lruvec *lruvec);
|
|
|
|
static inline struct pglist_data *lruvec_pgdat(struct lruvec *lruvec)
|
|
{
|
|
#ifdef CONFIG_MEMCG
|
|
return lruvec->pgdat;
|
|
#else
|
|
return container_of(lruvec, struct pglist_data, lruvec);
|
|
#endif
|
|
}
|
|
|
|
extern unsigned long lruvec_lru_size(struct lruvec *lruvec, enum lru_list lru);
|
|
|
|
#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_HAVE_MEMORYLESS_NODES
|
|
int local_memory_node(int node_id);
|
|
#else
|
|
static inline int local_memory_node(int node_id) { return node_id; };
|
|
#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)
|
|
|
|
/*
|
|
* Returns true if a zone has pages managed by the buddy allocator.
|
|
* All the reclaim decisions have to use this function rather than
|
|
* populated_zone(). If the whole zone is reserved then we can easily
|
|
* end up with populated_zone() && !managed_zone().
|
|
*/
|
|
static inline bool managed_zone(struct zone *zone)
|
|
{
|
|
return zone->managed_pages;
|
|
}
|
|
|
|
/* Returns true if a zone has memory */
|
|
static inline bool populated_zone(struct zone *zone)
|
|
{
|
|
return zone->present_pages;
|
|
}
|
|
|
|
extern int movable_zone;
|
|
|
|
#ifdef CONFIG_HIGHMEM
|
|
static inline int zone_movable_is_highmem(void)
|
|
{
|
|
#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
|
|
return movable_zone == ZONE_HIGHMEM;
|
|
#else
|
|
return (ZONE_MOVABLE - 1) == ZONE_HIGHMEM;
|
|
#endif
|
|
}
|
|
#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
|
|
}
|
|
|
|
/**
|
|
* 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
|
|
return is_highmem_idx(zone_idx(zone));
|
|
#else
|
|
return 0;
|
|
#endif
|
|
}
|
|
|
|
/* These two functions are used to setup the per zone pages min values */
|
|
struct ctl_table;
|
|
int min_free_kbytes_sysctl_handler(struct ctl_table *, int,
|
|
void __user *, size_t *, loff_t *);
|
|
int watermark_scale_factor_sysctl_handler(struct ctl_table *, int,
|
|
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,
|
|
void __user *, size_t *, loff_t *);
|
|
int percpu_pagelist_fraction_sysctl_handler(struct ctl_table *, int,
|
|
void __user *, size_t *, loff_t *);
|
|
int sysctl_min_unmapped_ratio_sysctl_handler(struct ctl_table *, int,
|
|
void __user *, size_t *, loff_t *);
|
|
int sysctl_min_slab_ratio_sysctl_handler(struct ctl_table *, int,
|
|
void __user *, size_t *, loff_t *);
|
|
|
|
extern int numa_zonelist_order_handler(struct ctl_table *, int,
|
|
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 */
|
|
}
|
|
|
|
struct zoneref *__next_zones_zonelist(struct zoneref *z,
|
|
enum zone_type highest_zoneidx,
|
|
nodemask_t *nodes);
|
|
|
|
/**
|
|
* 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
|
|
*
|
|
* 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.
|
|
*/
|
|
static __always_inline struct zoneref *next_zones_zonelist(struct zoneref *z,
|
|
enum zone_type highest_zoneidx,
|
|
nodemask_t *nodes)
|
|
{
|
|
if (likely(!nodes && zonelist_zone_idx(z) <= highest_zoneidx))
|
|
return z;
|
|
return __next_zones_zonelist(z, highest_zoneidx, nodes);
|
|
}
|
|
|
|
/**
|
|
* 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)
|
|
{
|
|
return next_zones_zonelist(zonelist->_zonerefs,
|
|
highest_zoneidx, nodes);
|
|
}
|
|
|
|
/**
|
|
* 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 = zonelist_zone(z); \
|
|
zone; \
|
|
z = next_zones_zonelist(++z, highidx, nodemask), \
|
|
zone = zonelist_zone(z))
|
|
|
|
#define for_next_zone_zonelist_nodemask(zone, z, zlist, highidx, nodemask) \
|
|
for (zone = z->zone; \
|
|
zone; \
|
|
z = next_zones_zonelist(++z, highidx, nodemask), \
|
|
zone = zonelist_zone(z))
|
|
|
|
|
|
/**
|
|
* 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_HAVE_MEMBLOCK_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
|
|
|
|
#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 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
|
|
|
|
#define pfn_to_section_nr(pfn) ((pfn) >> PFN_SECTION_SHIFT)
|
|
#define section_nr_to_pfn(sec) ((sec) << PFN_SECTION_SHIFT)
|
|
|
|
#define SECTION_ALIGN_UP(pfn) (((pfn) + PAGES_PER_SECTION - 1) & PAGE_SECTION_MASK)
|
|
#define SECTION_ALIGN_DOWN(pfn) ((pfn) & PAGE_SECTION_MASK)
|
|
|
|
struct page;
|
|
struct page_ext;
|
|
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_PAGE_EXTENSION
|
|
/*
|
|
* If SPARSEMEM, pgdat doesn't have page_ext pointer. We use
|
|
* section. (see page_ext.h about this.)
|
|
*/
|
|
struct page_ext *page_ext;
|
|
unsigned long pad;
|
|
#endif
|
|
/*
|
|
* WARNING: mem_section must be a power-of-2 in size for the
|
|
* calculation and use of SECTION_ROOT_MASK to make sense.
|
|
*/
|
|
};
|
|
|
|
#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 DIV_ROUND_UP(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));
|
|
}
|
|
|
|
#ifndef CONFIG_HAVE_ARCH_PFN_VALID
|
|
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)));
|
|
}
|
|
#endif
|
|
|
|
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 */
|
|
|
|
/*
|
|
* During memory init memblocks map pfns to nids. The search is expensive and
|
|
* this caches recent lookups. The implementation of __early_pfn_to_nid
|
|
* may treat start/end as pfns or sections.
|
|
*/
|
|
struct mminit_pfnnid_cache {
|
|
unsigned long last_start;
|
|
unsigned long last_end;
|
|
int last_nid;
|
|
};
|
|
|
|
#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.
|
|
*/
|
|
bool memmap_valid_within(unsigned long pfn,
|
|
struct page *page, struct zone *zone);
|
|
#else
|
|
static inline bool memmap_valid_within(unsigned long pfn,
|
|
struct page *page, struct zone *zone)
|
|
{
|
|
return true;
|
|
}
|
|
#endif /* CONFIG_ARCH_HAS_HOLES_MEMORYMODEL */
|
|
|
|
#endif /* !__GENERATING_BOUNDS.H */
|
|
#endif /* !__ASSEMBLY__ */
|
|
#endif /* _LINUX_MMZONE_H */
|