]> err.no Git - linux-2.6/commit
hugetlb: Try to grow hugetlb pool for MAP_SHARED mappings
authorAdam Litke <agl@us.ibm.com>
Tue, 16 Oct 2007 08:26:19 +0000 (01:26 -0700)
committerLinus Torvalds <torvalds@woody.linux-foundation.org>
Tue, 16 Oct 2007 16:43:02 +0000 (09:43 -0700)
commite4e574b767ba63101cfda2b42d72f38546319297
tree084b94d01c71ccd898f8df0ec441e6726e657e75
parent7893d1d505d59db9d4f35165c8b6d3c6dff40a32
hugetlb: Try to grow hugetlb pool for MAP_SHARED mappings

Shared mappings require special handling because the huge pages needed to
fully populate the VMA must be reserved at mmap time.  If not enough pages are
available when making the reservation, allocate all of the shortfall at once
from the buddy allocator and add the pages directly to the hugetlb pool.  If
they cannot be allocated, then fail the mapping.  The page surplus is
accounted for in the same way as for private mappings; faulted surplus pages
will be freed at unmap time.  Reserved, surplus pages that have not been used
must be freed separately when their reservation has been released.

Signed-off-by: Adam Litke <agl@us.ibm.com>
Acked-by: Andy Whitcroft <apw@shadowen.org>
Acked-by: Dave McCracken <dave.mccracken@oracle.com>
Cc: William Irwin <bill.irwin@oracle.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Ken Chen <kenchen@google.com>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm/hugetlb.c