| #ifndef _LINUX_MMZONE_H |
| #define _LINUX_MMZONE_H |
| |
| #ifdef __KERNEL__ |
| #ifndef __ASSEMBLY__ |
| |
| #include <linux/config.h> |
| #include <linux/spinlock.h> |
| #include <linux/list.h> |
| #include <linux/wait.h> |
| #include <linux/cache.h> |
| #include <linux/threads.h> |
| #include <linux/numa.h> |
| #include <linux/init.h> |
| #include <asm/atomic.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 |
| |
| struct free_area { |
| struct list_head free_list; |
| unsigned long nr_free; |
| }; |
| |
| struct pglist_data; |
| |
| /* |
| * zone->lock and 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_maxaligned_in_smp; |
| #define ZONE_PADDING(name) struct zone_padding name; |
| #else |
| #define ZONE_PADDING(name) |
| #endif |
| |
| struct per_cpu_pages { |
| int count; /* number of pages in the list */ |
| int low; /* low watermark, refill needed */ |
| int high; /* high watermark, emptying needed */ |
| int batch; /* chunk size for buddy add/remove */ |
| struct list_head list; /* the list of pages */ |
| }; |
| |
| 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 */ |
| #endif |
| } ____cacheline_aligned_in_smp; |
| |
| #ifdef CONFIG_NUMA |
| #define zone_pcp(__z, __cpu) ((__z)->pageset[(__cpu)]) |
| #else |
| #define zone_pcp(__z, __cpu) (&(__z)->pageset[(__cpu)]) |
| #endif |
| |
| #define ZONE_DMA 0 |
| #define ZONE_NORMAL 1 |
| #define ZONE_HIGHMEM 2 |
| |
| #define MAX_NR_ZONES 3 /* Sync this with ZONES_SHIFT */ |
| #define ZONES_SHIFT 2 /* ceil(log2(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". |
| */ |
| #define GFP_ZONEMASK 0x03 |
| /* |
| * 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 when the left most bit is not a "loner", otherwise |
| * use the second. |
| */ |
| /* #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 PC we have 3 zones: |
| * |
| * ZONE_DMA < 16 MB ISA DMA capable memory |
| * ZONE_NORMAL 16-896 MB direct mapped by the kernel |
| * ZONE_HIGHMEM > 896 MB only page cache and user processes |
| */ |
| |
| struct zone { |
| /* Fields commonly accessed by the page allocator */ |
| unsigned long free_pages; |
| unsigned long pages_min, pages_low, pages_high; |
| /* |
| * 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's tons of freeable ram |
| * on the higher zones). This array is recalculated at runtime if the |
| * sysctl_lowmem_reserve_ratio sysctl changes. |
| */ |
| unsigned long lowmem_reserve[MAX_NR_ZONES]; |
| |
| #ifdef CONFIG_NUMA |
| struct per_cpu_pageset *pageset[NR_CPUS]; |
| #else |
| struct per_cpu_pageset pageset[NR_CPUS]; |
| #endif |
| /* |
| * free areas of different sizes |
| */ |
| spinlock_t lock; |
| struct free_area free_area[MAX_ORDER]; |
| |
| |
| ZONE_PADDING(_pad1_) |
| |
| /* Fields commonly accessed by the page reclaim scanner */ |
| spinlock_t lru_lock; |
| struct list_head active_list; |
| struct list_head inactive_list; |
| unsigned long nr_scan_active; |
| unsigned long nr_scan_inactive; |
| unsigned long nr_active; |
| unsigned long nr_inactive; |
| unsigned long pages_scanned; /* since last reclaim */ |
| int all_unreclaimable; /* All pages pinned */ |
| |
| /* |
| * Does the allocator try to reclaim pages from the zone as soon |
| * as it fails a watermark_ok() in __alloc_pages? |
| */ |
| int reclaim_pages; |
| /* A count of how many reclaimers are scanning this zone */ |
| atomic_t reclaim_in_progress; |
| |
| /* |
| * prev_priority holds the scanning priority for this zone. It is |
| * defined as the scanning priority at which we achieved our reclaim |
| * target at the previous try_to_free_pages() or balance_pgdat() |
| * invokation. |
| * |
| * We use prev_priority as a measure of how much stress page reclaim 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 |
| * it is expected to average out OK. |
| */ |
| int temp_priority; |
| int prev_priority; |
| |
| |
| ZONE_PADDING(_pad2_) |
| /* Rarely used or read-mostly fields */ |
| |
| /* |
| * wait_table -- the array holding the hash table |
| * wait_table_size -- 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 |
| * waiting for a page to become available and make them |
| * runnable again when possible. The trouble is that this |
| * consumes a lot of space, especially when so few things |
| * wait on pages at a given time. So instead of using |
| * per-page waitqueues, we use a waitqueue hash table. |
| * |
| * The bucket discipline is to sleep on the same queue when |
| * colliding and wake all in that wait queue when removing. |
| * When something wakes, it must check to be sure its page is |
| * truly available, a la thundering herd. The cost of a |
| * collision is great, but given the expected load of the |
| * table, they should be so rare as to be outweighed by the |
| * benefits from the saved space. |
| * |
| * __wait_on_page_locked() and unlock_page() in mm/filemap.c, are the |
| * primary users of these fields, and in mm/page_alloc.c |
| * free_area_init_core() performs the initialization of them. |
| */ |
| wait_queue_head_t * wait_table; |
| unsigned long wait_table_size; |
| 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; |
| |
| unsigned long spanned_pages; /* total size, including holes */ |
| unsigned long present_pages; /* amount of memory (excluding holes) */ |
| |
| /* |
| * rarely used fields: |
| */ |
| char *name; |
| } ____cacheline_maxaligned_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 |
| * queues ("queue_length >> 12") during an aging round. |
| */ |
| #define DEF_PRIORITY 12 |
| |
| /* |
| * 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. |
| */ |
| struct zonelist { |
| struct zone *zones[MAX_NUMNODES * MAX_NR_ZONES + 1]; // NULL delimited |
| }; |
| |
| |
| /* |
| * 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[GFP_ZONETYPES]; |
| int nr_zones; |
| #ifdef CONFIG_FLAT_NODE_MEM_MAP |
| struct page *node_mem_map; |
| #endif |
| struct bootmem_data *bdata; |
| 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; |
| struct pglist_data *pgdat_next; |
| 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)) |
| |
| 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, |
| 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 alloc_type, int can_try_harder, int gfp_high); |
| |
| #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) |
| |
| /** |
| * 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 is_highmem_idx(int idx) |
| { |
| return (idx == ZONE_HIGHMEM); |
| } |
| |
| static inline int is_normal_idx(int 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) |
| { |
| return zone == zone->zone_pgdat->node_zones + ZONE_HIGHMEM; |
| } |
| |
| static inline int is_normal(struct zone *zone) |
| { |
| return zone == zone->zone_pgdat->node_zones + ZONE_NORMAL; |
| } |
| |
| /* 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 *); |
| |
| #include <linux/topology.h> |
| /* Returns the number of the current Node. */ |
| #define numa_node_id() (cpu_to_node(raw_smp_processor_id())) |
| |
| #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 |
| #define MAX_NODES_SHIFT 1 |
| #define pfn_to_nid(pfn) (0) |
| |
| #else /* CONFIG_NEED_MULTIPLE_NODES */ |
| |
| #include <asm/mmzone.h> |
| |
| #endif /* !CONFIG_NEED_MULTIPLE_NODES */ |
| |
| #ifdef CONFIG_SPARSEMEM |
| #include <asm/sparsemem.h> |
| #endif |
| |
| #if BITS_PER_LONG == 32 || defined(ARCH_HAS_ATOMIC_UNSIGNED) |
| /* |
| * with 32 bit page->flags field, we reserve 8 bits for node/zone info. |
| * there are 3 zones (2 bits) and this leaves 8-2=6 bits for nodes. |
| */ |
| #define FLAGS_RESERVED 8 |
| |
| #elif BITS_PER_LONG == 64 |
| /* |
| * with 64 bit flags field, there's plenty of room. |
| */ |
| #define FLAGS_RESERVED 32 |
| |
| #else |
| |
| #error BITS_PER_LONG not defined |
| |
| #endif |
| |
| #ifndef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID |
| #define early_pfn_to_nid(nid) (0UL) |
| #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)) |
| |
| #if (MAX_ORDER - 1 + PAGE_SHIFT) > SECTION_SIZE_BITS |
| #error Allocator MAX_ORDER exceeds SECTION_SIZE |
| #endif |
| |
| struct page; |
| struct mem_section { |
| struct page *section_mem_map; |
| }; |
| |
| extern struct mem_section mem_section[NR_MEM_SECTIONS]; |
| |
| /* |
| * Given a kernel address, find the home node of the underlying memory. |
| */ |
| #define kvaddr_to_nid(kaddr) pfn_to_nid(__pa(kaddr) >> PAGE_SHIFT) |
| |
| static inline struct mem_section *__pfn_to_section(unsigned long pfn) |
| { |
| return &mem_section[pfn_to_section_nr(pfn)]; |
| } |
| |
| #define pfn_to_page(pfn) \ |
| ({ \ |
| unsigned long __pfn = (pfn); \ |
| __pfn_to_section(__pfn)->section_mem_map + __pfn; \ |
| }) |
| #define page_to_pfn(page) \ |
| ({ \ |
| page - mem_section[page_to_section(page)].section_mem_map; \ |
| }) |
| |
| static inline int pfn_valid(unsigned long pfn) |
| { |
| if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS) |
| return 0; |
| return mem_section[pfn_to_section_nr(pfn)].section_mem_map != 0; |
| } |
| |
| /* |
| * 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 early_pfn_to_nid |
| #endif |
| |
| #define pfn_to_pgdat(pfn) \ |
| ({ \ |
| NODE_DATA(pfn_to_nid(pfn)); \ |
| }) |
| |
| #define early_pfn_valid(pfn) pfn_valid(pfn) |
| void sparse_init(void); |
| #else |
| #define sparse_init() do {} while (0) |
| #endif /* CONFIG_SPARSEMEM */ |
| |
| #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); |
| |
| #endif /* !__ASSEMBLY__ */ |
| #endif /* __KERNEL__ */ |
| #endif /* _LINUX_MMZONE_H */ |