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author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-11-13 16:57:25 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-11-13 16:57:25 -0800 |
commit | 971ad4e4d6833d5f250d0db332ff863c599ae19f (patch) | |
tree | b618d2007229bd8972d685c98b9cbd739f96b979 /mm/internal.h | |
parent | b0ab3f190e7331a83b397a0e772cbc01bf18201f (diff) | |
parent | 8fe671fc0b9f5a0d013153a9ddbd979d6eff0547 (diff) |
Merge branch 'akpm' (fixes from Andrew Morton)
Merge misc fixes from Andrew Morton:
"15 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
MAINTAINERS: add IIO include files
kernel/panic.c: update comments for print_tainted
mem-hotplug: reset node present pages when hot-adding a new pgdat
mem-hotplug: reset node managed pages when hot-adding a new pgdat
mm/debug-pagealloc: correct freepage accounting and order resetting
fanotify: fix notification of groups with inode & mount marks
mm, compaction: prevent infinite loop in compact_zone
mm: alloc_contig_range: demote pages busy message from warn to info
mm/slab: fix unalignment problem on Malta with EVA due to slab merge
mm/page_alloc: restrict max order of merging on isolated pageblock
mm/page_alloc: move freepage counting logic to __free_one_page()
mm/page_alloc: add freepage on isolate pageblock to correct buddy list
mm/page_alloc: fix incorrect isolation behavior by rechecking migratetype
mm/compaction: skip the range until proper target pageblock is met
zram: avoid kunmap_atomic() of a NULL pointer
Diffstat (limited to 'mm/internal.h')
-rw-r--r-- | mm/internal.h | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/mm/internal.h b/mm/internal.h index 829304090b90..a4f90ba7068e 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -108,6 +108,31 @@ extern pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address); /* * in mm/page_alloc.c */ + +/* + * Locate the struct page for both the matching buddy in our + * pair (buddy1) and the combined O(n+1) page they form (page). + * + * 1) Any buddy B1 will have an order O twin B2 which satisfies + * the following equation: + * B2 = B1 ^ (1 << O) + * For example, if the starting buddy (buddy2) is #8 its order + * 1 buddy is #10: + * B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10 + * + * 2) Any buddy B will have an order O+1 parent P which + * satisfies the following equation: + * P = B & ~(1 << O) + * + * Assumption: *_mem_map is contiguous at least up to MAX_ORDER + */ +static inline unsigned long +__find_buddy_index(unsigned long page_idx, unsigned int order) +{ + return page_idx ^ (1 << order); +} + +extern int __isolate_free_page(struct page *page, unsigned int order); extern void __free_pages_bootmem(struct page *page, unsigned int order); extern void prep_compound_page(struct page *page, unsigned long order); #ifdef CONFIG_MEMORY_FAILURE |