mm, page_owner: dump page owner info from dump_page()
The page_owner mechanism is useful for dealing with memory leaks. By
reading /sys/kernel/debug/page_owner one can determine the stack traces
leading to allocations of all pages, and find e.g. a buggy driver.
This information might be also potentially useful for debugging, such as
the VM_BUG_ON_PAGE() calls to dump_page(). So let's print the stored
info from dump_page().
Example output:
page:
ffffea000292f1c0 count:1 mapcount:0 mapping:
ffff8800b2f6cc18 index:0x91d
flags: 0x1fffff8001002c(referenced|uptodate|lru|mappedtodisk)
page dumped because: VM_BUG_ON_PAGE(1)
page->mem_cgroup:
ffff8801392c5000
page allocated via order 0, migratetype Movable, gfp_mask 0x24213ca(GFP_HIGHUSER_MOVABLE|__GFP_COLD|__GFP_NOWARN|__GFP_NORETRY)
[<
ffffffff811682c4>] __alloc_pages_nodemask+0x134/0x230
[<
ffffffff811b40c8>] alloc_pages_current+0x88/0x120
[<
ffffffff8115e386>] __page_cache_alloc+0xe6/0x120
[<
ffffffff8116ba6c>] __do_page_cache_readahead+0xdc/0x240
[<
ffffffff8116bd05>] ondemand_readahead+0x135/0x260
[<
ffffffff8116be9c>] page_cache_async_readahead+0x6c/0x70
[<
ffffffff811604c2>] generic_file_read_iter+0x3f2/0x760
[<
ffffffff811e0dc7>] __vfs_read+0xa7/0xd0
page has been migrated, last migrate reason: compaction
Change-Id: Ie5f3716ab34b3a66a00973f5d87360ebd0155348
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-commit:
4e462112e98f9ad6dd62e160f8b14c7df5fed2fc
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Prakash Gupta <guptap@codeaurora.org>