thp: setup huge zero page on non-write page fault
authorKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Wed, 12 Dec 2012 21:51:02 +0000 (13:51 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 13 Dec 2012 01:38:31 +0000 (17:38 -0800)
commit80371957f09814d25c38733d2d08de47f59a13c2
tree2ebdedfa3a10af22941e44729f1c4c2623e8da74
parentc5a647d09fe9fc3e0241c89845cf8e6220b916f5
thp: setup huge zero page on non-write page fault

All code paths seems covered. Now we can map huge zero page on read page
fault.

We setup it in do_huge_pmd_anonymous_page() if area around fault address
is suitable for THP and we've got read page fault.

If we fail to setup huge zero page (ENOMEM) we fallback to
handle_pte_fault() as we normally do in THP.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@linux.intel.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm/huge_memory.c