]> git.proxmox.com Git - mirror_ubuntu-eoan-kernel.git/commit
mm, thp: do not allow thp faults to avoid cpuset restrictions
authorDavid Rientjes <rientjes@google.com>
Wed, 30 Jul 2014 23:08:24 +0000 (16:08 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 31 Jul 2014 00:16:13 +0000 (17:16 -0700)
commitb104a35d32025ca740539db2808aa3385d0f30eb
tree60e0ba241083b6fea6d85a7181225e918c9f7ff5
parentf6789593d5cea42a4ecb1cbeab6a23ade5ebbba7
mm, thp: do not allow thp faults to avoid cpuset restrictions

The page allocator relies on __GFP_WAIT to determine if ALLOC_CPUSET
should be set in allocflags.  ALLOC_CPUSET controls if a page allocation
should be restricted only to the set of allowed cpuset mems.

Transparent hugepages clears __GFP_WAIT when defrag is disabled to prevent
the fault path from using memory compaction or direct reclaim.  Thus, it
is unfairly able to allocate outside of its cpuset mems restriction as a
side-effect.

This patch ensures that ALLOC_CPUSET is only cleared when the gfp mask is
truly GFP_ATOMIC by verifying it is also not a thp allocation.

Signed-off-by: David Rientjes <rientjes@google.com>
Reported-by: Alex Thorlton <athorlton@sgi.com>
Tested-by: Alex Thorlton <athorlton@sgi.com>
Cc: Bob Liu <lliubbo@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Hedi Berriche <hedi@sgi.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm/page_alloc.c