thp: implement splitting pmd for huge zero page
authorKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Wed, 12 Dec 2012 21:51:00 +0000 (13:51 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 13 Dec 2012 01:38:31 +0000 (17:38 -0800)
commitc5a647d09fe9fc3e0241c89845cf8e6220b916f5
tree6d436d79bfb11b202da4de02a7cd1e6e3ee38847
parente180377f1ae48b3cbc559c9875d9b038f7f000c6
thp: implement splitting pmd for huge zero page

We can't split huge zero page itself (and it's bug if we try), but we
can split the pmd which points to it.

On splitting the pmd we create a table with all ptes set to normal zero
page.

[akpm@linux-foundation.org: fix build error]
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