#ifdef __KERNEL__
#ifndef __ASSEMBLY__
-#include <linux/config.h>
#include <linux/spinlock.h>
#include <linux/list.h>
#include <linux/wait.h>
#include <linux/numa.h>
#include <linux/init.h>
#include <linux/seqlock.h>
+#include <linux/nodemask.h>
#include <asm/atomic.h>
+#include <asm/page.h>
/* Free memory management - zoned buddy allocator. */
#ifndef CONFIG_FORCE_MAX_ZONEORDER
#else
#define MAX_ORDER CONFIG_FORCE_MAX_ZONEORDER
#endif
+#define MAX_ORDER_NR_PAGES (1 << (MAX_ORDER - 1))
struct free_area {
struct list_head free_list;
#define ZONE_PADDING(name)
#endif
+enum zone_stat_item {
+ NR_ANON_PAGES, /* Mapped anonymous pages */
+ NR_FILE_MAPPED, /* pagecache pages mapped into pagetables.
+ only modified from process context */
+ NR_FILE_PAGES,
+ NR_SLAB_RECLAIMABLE,
+ NR_SLAB_UNRECLAIMABLE,
+ NR_PAGETABLE, /* used for pagetables */
+ NR_FILE_DIRTY,
+ NR_WRITEBACK,
+ NR_UNSTABLE_NFS, /* NFS unstable pages */
+ NR_BOUNCE,
+ NR_VMSCAN_WRITE,
+#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_VM_ZONE_STAT_ITEMS };
+
struct per_cpu_pages {
int count; /* number of pages in the list */
int high; /* high watermark, emptying needed */
struct per_cpu_pageset {
struct per_cpu_pages pcp[2]; /* 0: hot. 1: cold */
-#ifdef CONFIG_NUMA
- unsigned long numa_hit; /* allocated in intended node */
- unsigned long numa_miss; /* allocated in non intended node */
- unsigned long numa_foreign; /* was intended here, hit elsewhere */
- unsigned long interleave_hit; /* interleaver prefered this zone */
- unsigned long local_node; /* allocation from local node */
- unsigned long other_node; /* allocation from other node */
+#ifdef CONFIG_SMP
+ s8 stat_threshold;
+ s8 vm_stat_diff[NR_VM_ZONE_STAT_ITEMS];
#endif
} ____cacheline_aligned_in_smp;
#define zone_pcp(__z, __cpu) (&(__z)->pageset[(__cpu)])
#endif
-#define ZONE_DMA 0
-#define ZONE_DMA32 1
-#define ZONE_NORMAL 2
-#define ZONE_HIGHMEM 3
-
-#define MAX_NR_ZONES 4 /* Sync this with ZONES_SHIFT */
-#define ZONES_SHIFT 2 /* ceil(log2(MAX_NR_ZONES)) */
-
+enum zone_type {
+ /*
+ * 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
+ * arm26 <48M
+ * arm Various
+ * alpha Unlimited or 0-16MB.
+ *
+ * i386, x86_64 and multiple other arches
+ * <16M.
+ */
+ ZONE_DMA,
+#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
+ MAX_NR_ZONES
+};
/*
* When a memory allocation must conform to specific limitations (such
* as being suitable for DMA) the caller will pass in hints to the
* allocator in the gfp_mask, in the zone modifier bits. These bits
* are used to select a priority ordered list of memory zones which
- * match the requested limits. GFP_ZONEMASK defines which bits within
- * the gfp_mask should be considered as zone modifiers. Each valid
- * combination of the zone modifier bits has a corresponding list
- * of zones (in node_zonelists). Thus for two zone modifiers there
- * will be a maximum of 4 (2 ** 2) zonelists, for 3 modifiers there will
- * be 8 (2 ** 3) zonelists. GFP_ZONETYPES defines the number of possible
- * combinations of zone modifiers in "zone modifier space".
- *
- * As an optimisation any zone modifier bits which are only valid when
- * no other zone modifier bits are set (loners) should be placed in
- * the highest order bits of this field. This allows us to reduce the
- * extent of the zonelists thus saving space. For example in the case
- * of three zone modifier bits, we could require up to eight zonelists.
- * If the left most zone modifier is a "loner" then the highest valid
- * zonelist would be four allowing us to allocate only five zonelists.
- * Use the first form for GFP_ZONETYPES when the left most bit is not
- * a "loner", otherwise use the second.
- *
- * NOTE! Make sure this matches the zones in <linux/gfp.h>
+ * match the requested limits. See gfp_zone() in include/linux/gfp.h
*/
-#define GFP_ZONEMASK 0x07
-/* #define GFP_ZONETYPES (GFP_ZONEMASK + 1) */ /* Non-loner */
-#define GFP_ZONETYPES ((GFP_ZONEMASK + 1) / 2 + 1) /* Loner */
-/*
- * On machines where it is needed (eg PCs) we divide physical memory
- * into multiple physical zones. On a 32bit PC we have 4 zones:
- *
- * ZONE_DMA < 16 MB ISA DMA capable memory
- * ZONE_DMA32 0 MB Empty
- * ZONE_NORMAL 16-896 MB direct mapped by the kernel
- * ZONE_HIGHMEM > 896 MB only page cache and user processes
- */
+#if !defined(CONFIG_ZONE_DMA32) && !defined(CONFIG_HIGHMEM)
+#define ZONES_SHIFT 1
+#else
+#define ZONES_SHIFT 2
+#endif
struct zone {
/* Fields commonly accessed by the page allocator */
unsigned long lowmem_reserve[MAX_NR_ZONES];
#ifdef CONFIG_NUMA
+ int node;
+ /*
+ * zone reclaim becomes active if more unmapped pages exist.
+ */
+ unsigned long min_unmapped_pages;
+ unsigned long min_slab_pages;
struct per_cpu_pageset *pageset[NR_CPUS];
#else
struct per_cpu_pageset pageset[NR_CPUS];
/* A count of how many reclaimers are scanning this zone */
atomic_t reclaim_in_progress;
- /*
- * timestamp (in jiffies) of the last zone reclaim that did not
- * result in freeing of pages. This is used to avoid repeated scans
- * if all memory in the zone is in use.
- */
- unsigned long last_unsuccessful_zone_reclaim;
+ /* Zone statistics */
+ atomic_long_t vm_stat[NR_VM_ZONE_STAT_ITEMS];
/*
* prev_priority holds the scanning priority for this zone. It is
* under - it drives the swappiness decision: whether to unmap mapped
* pages.
*
- * temp_priority is used to remember the scanning priority at which
- * this zone was successfully refilled to free_pages == pages_high.
- *
- * Access to both these fields is quite racy even on uniprocessor. But
+ * Access to both this field is quite racy even on uniprocessor. But
* it is expected to average out OK.
*/
- int temp_priority;
int prev_priority;
/*
* wait_table -- the array holding the hash table
- * wait_table_size -- the size of the hash table array
+ * wait_table_hash_nr_entries -- the size of the hash table array
* wait_table_bits -- wait_table_size == (1 << wait_table_bits)
*
* The purpose of all these is to keep track of the people
* free_area_init_core() performs the initialization of them.
*/
wait_queue_head_t * wait_table;
- unsigned long wait_table_size;
+ unsigned long wait_table_hash_nr_entries;
unsigned long wait_table_bits;
/*
* Discontig memory support fields.
*/
struct pglist_data *zone_pgdat;
- struct page *zone_mem_map;
/* zone_start_pfn == zone_start_paddr >> PAGE_SHIFT */
unsigned long zone_start_pfn;
/*
* rarely used fields:
*/
- char *name;
+ const char *name;
} ____cacheline_internodealigned_in_smp;
-
/*
* 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
*/
#define DEF_PRIORITY 12
+/* Maximum number of zones on a zonelist */
+#define MAX_ZONES_PER_ZONELIST (MAX_NUMNODES * MAX_NR_ZONES)
+
+#ifdef CONFIG_NUMA
+/*
+ * We cache key information from each zonelist for smaller cache
+ * footprint when scanning for free pages in get_page_from_freelist().
+ *
+ * 1) The BITMAP fullzones tracks which zones in a zonelist have come
+ * up short of free memory since the last time (last_fullzone_zap)
+ * we zero'd fullzones.
+ * 2) The array z_to_n[] maps each zone in the zonelist to its node
+ * 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
+struct zonelist_cache;
+#endif
+
/*
* 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.
*
- * Right now a zonelist takes up less than a cacheline. We never
- * modify it apart from boot-up, and only a few indices are used,
- * so despite the zonelist table being relatively big, the cache
- * footprint of this construct is very small.
+ * 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.
*/
+
struct zonelist {
- struct zone *zones[MAX_NUMNODES * MAX_NR_ZONES + 1]; // NULL delimited
+ struct zonelist_cache *zlcache_ptr; // NULL or &zlcache
+ struct zone *zones[MAX_ZONES_PER_ZONELIST + 1]; // NULL delimited
+#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
struct bootmem_data;
typedef struct pglist_data {
struct zone node_zones[MAX_NR_ZONES];
- struct zonelist node_zonelists[GFP_ZONETYPES];
+ struct zonelist node_zonelists[MAX_NR_ZONES];
int nr_zones;
#ifdef CONFIG_FLAT_NODE_MEM_MAP
struct page *node_mem_map;
unsigned long node_spanned_pages; /* total size of physical page
range, including holes */
int node_id;
- struct pglist_data *pgdat_next;
wait_queue_head_t kswapd_wait;
struct task_struct *kswapd;
int kswapd_max_order;
#include <linux/memory_hotplug.h>
-extern struct pglist_data *pgdat_list;
-
void __get_zone_counts(unsigned long *active, unsigned long *inactive,
unsigned long *free, struct pglist_data *pgdat);
void get_zone_counts(unsigned long *active, unsigned long *inactive,
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);
*/
#define zone_idx(zone) ((zone) - (zone)->zone_pgdat->node_zones)
-/**
- * for_each_pgdat - helper macro to iterate over all nodes
- * @pgdat - pointer to a pg_data_t variable
- *
- * Meant to help with common loops of the form
- * pgdat = pgdat_list;
- * while(pgdat) {
- * ...
- * pgdat = pgdat->pgdat_next;
- * }
- */
-#define for_each_pgdat(pgdat) \
- for (pgdat = pgdat_list; pgdat; pgdat = pgdat->pgdat_next)
-
-/*
- * next_zone - helper magic for for_each_zone()
- * Thanks to William Lee Irwin III for this piece of ingenuity.
- */
-static inline struct zone *next_zone(struct zone *zone)
-{
- pg_data_t *pgdat = zone->zone_pgdat;
-
- if (zone < pgdat->node_zones + MAX_NR_ZONES - 1)
- zone++;
- else if (pgdat->pgdat_next) {
- pgdat = pgdat->pgdat_next;
- zone = pgdat->node_zones;
- } else
- zone = NULL;
-
- return zone;
-}
-
-/**
- * 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. This basically means for_each_zone() is an
- * easier to read version of this piece of code:
- *
- * for (pgdat = pgdat_list; pgdat; pgdat = pgdat->node_next)
- * for (i = 0; i < MAX_NR_ZONES; ++i) {
- * struct zone * z = pgdat->node_zones + i;
- * ...
- * }
- * }
- */
-#define for_each_zone(zone) \
- for (zone = pgdat_list->node_zones; zone; zone = next_zone(zone))
-
static inline int populated_zone(struct zone *zone)
{
return (!!zone->present_pages);
}
-static inline int is_highmem_idx(int idx)
+static inline int is_highmem_idx(enum zone_type idx)
{
+#ifdef CONFIG_HIGHMEM
return (idx == ZONE_HIGHMEM);
+#else
+ return 0;
+#endif
}
-static inline int is_normal_idx(int idx)
+static inline int is_normal_idx(enum zone_type idx)
{
return (idx == ZONE_NORMAL);
}
*/
static inline int is_highmem(struct zone *zone)
{
+#ifdef CONFIG_HIGHMEM
return zone == zone->zone_pgdat->node_zones + ZONE_HIGHMEM;
+#else
+ return 0;
+#endif
}
static inline int is_normal(struct zone *zone)
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)
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 *);
#include <linux/topology.h>
/* Returns the number of the current Node. */
#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_pgdat - helper macro to iterate over all 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))
+
#ifdef CONFIG_SPARSEMEM
#include <asm/sparsemem.h>
#endif
#endif
-#ifndef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
+#if !defined(CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID) && \
+ !defined(CONFIG_ARCH_POPULATES_NODE_MAP)
#define early_pfn_to_nid(nid) (0UL)
#endif
* 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.
*/
#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)
{
return __nr_to_section(pfn_to_section_nr(pfn));
}
-#define pfn_to_page(pfn) \
-({ \
- unsigned long __pfn = (pfn); \
- __section_mem_map_addr(__pfn_to_section(__pfn)) + __pfn; \
-})
-#define page_to_pfn(page) \
-({ \
- page - __section_mem_map_addr(__nr_to_section( \
- page_to_section(page))); \
-})
-
static inline int pfn_valid(unsigned long pfn)
{
if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS)
#define sparse_index_init(_sec, _nid) do {} while (0)
#endif /* CONFIG_SPARSEMEM */
+#ifdef CONFIG_NODES_SPAN_OTHER_NODES
+#define early_pfn_in_nid(pfn, nid) (early_pfn_to_nid(pfn) == (nid))
+#else
+#define early_pfn_in_nid(pfn, nid) (1)
+#endif
+
#ifndef early_pfn_valid
#define early_pfn_valid(pfn) (1)
#endif
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