diff options
Diffstat (limited to 'include/linux/mmzone.h')
| -rw-r--r-- | include/linux/mmzone.h | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 7519eb4191e..f5fa3082fd6 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -12,6 +12,7 @@ #include <linux/threads.h> #include <linux/numa.h> #include <linux/init.h> +#include <linux/seqlock.h> #include <asm/atomic.h> /* Free memory management - zoned buddy allocator. */ @@ -137,6 +138,10 @@ struct zone { * free areas of different sizes */ spinlock_t lock; +#ifdef CONFIG_MEMORY_HOTPLUG + /* see spanned/present_pages for more description */ + seqlock_t span_seqlock; +#endif struct free_area free_area[MAX_ORDER]; @@ -220,6 +225,16 @@ struct zone { /* zone_start_pfn == zone_start_paddr >> PAGE_SHIFT */ unsigned long zone_start_pfn; + /* + * zone_start_pfn, spanned_pages and present_pages are all + * 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 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. + */ unsigned long spanned_pages; /* total size, including holes */ unsigned long present_pages; /* amount of memory (excluding holes) */ @@ -273,6 +288,16 @@ typedef struct pglist_data { struct page *node_mem_map; #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 @@ -293,6 +318,8 @@ typedef struct pglist_data { #endif #define nid_page_nr(nid, pagenr) pgdat_page_nr(NODE_DATA(nid),(pagenr)) +#include <linux/memory_hotplug.h> + extern struct pglist_data *pgdat_list; void __get_zone_counts(unsigned long *active, unsigned long *inactive, @@ -509,6 +536,7 @@ static inline struct mem_section *__nr_to_section(unsigned long nr) return NULL; return &mem_section[SECTION_NR_TO_ROOT(nr)][nr & SECTION_ROOT_MASK]; } +extern int __section_nr(struct mem_section* ms); /* * We use the lower bits of the mem_map pointer to store |