tag name0.4-1
Tagged objectcommit 80a71e08f3...
'10' name='q' value=''/>
path: root/include/linux
diff options
authorVlastimil Babka <>2016-03-15 14:56:18 -0700
committerLinus Torvalds <>2016-03-15 16:55:16 -0700
commit7cd12b4abfd2f8f42414c520bbd051a5b7dc7a8c (patch)
treeaddc9efb62517cb685561fc50d9645bfd9a0b30a /include/linux
parentd435edca928805074dae005ab9a42d9fa60fc702 (diff)
mm, page_owner: track and print last migrate reason
During migration, page_owner info is now copied with the rest of the page, so the stacktrace leading to free page allocation during migration is overwritten. For debugging purposes, it might be however useful to know that the page has been migrated since its initial allocation. This might happen many times during the lifetime for different reasons and fully tracking this, especially with stacktraces would incur extra memory costs. As a compromise, store and print the migrate_reason of the last migration that occurred to the page. This is enough to distinguish compaction, numa balancing etc. Example page_owner entry after the patch: Page allocated via order 0, mask 0x24200ca(GFP_HIGHUSER_MOVABLE) PFN 628753 type Movable Block 1228 type Movable Flags 0x1fffff80040030(dirty|lru|swapbacked) [<ffffffff811682c4>] __alloc_pages_nodemask+0x134/0x230 [<ffffffff811b6325>] alloc_pages_vma+0xb5/0x250 [<ffffffff81177491>] shmem_alloc_page+0x61/0x90 [<ffffffff8117a438>] shmem_getpage_gfp+0x678/0x960 [<ffffffff8117c2b9>] shmem_fallocate+0x329/0x440 [<ffffffff811de600>] vfs_fallocate+0x140/0x230 [<ffffffff811df434>] SyS_fallocate+0x44/0x70 [<ffffffff8158cc2e>] entry_SYSCALL_64_fastpath+0x12/0x71 Page has been migrated, last migrate reason: compaction Signed-off-by: Vlastimil Babka <> Cc: Joonsoo Kim <> Cc: Minchan Kim <> Cc: Sasha Levin <> Cc: "Kirill A. Shutemov" <> Cc: Mel Gorman <> Cc: Michal Hocko <> Cc: Hugh Dickins <> Signed-off-by: Andrew Morton <> Signed-off-by: Linus Torvalds <>
Diffstat (limited to 'include/linux')
3 files changed, 15 insertions, 1 deletions
diff --git a/include/linux/migrate.h b/include/linux/migrate.h