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 <[email protected]>
Reported-by: Alex Thorlton <[email protected]>
Tested-by: Alex Thorlton <[email protected]>
Cc: Bob Liu <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: Hedi Berriche <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: Johannes Weiner <[email protected]>
Cc: Kirill A. Shutemov <[email protected]>
Cc: Mel Gorman <[email protected]>
Cc: Rik van Riel <[email protected]>
Cc: Srivatsa S. Bhat <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

0 files changed, 0 insertions, 0 deletions