tree a7b235f4f15f1ce40e27cf40a126c1b86888034a
parent bdcde42d74a12e170971038671a80ef00603ae4e
author Wanpeng Li <liwanp@linux.vnet.ibm.com> 1364870774 +0800
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> 1364932191 -0700

staging: zcache: zero-filled pages awareness

Compression of zero-filled pages can unneccessarily cause internal
fragmentation, and thus waste memory. This special case can be
optimized.

This patch captures zero-filled pages, and marks their corresponding
zcache backing page entry as zero-filled. Whenever such zero-filled
page is retrieved, we fill the page frame with zero.

Acked-by: Dan Magenheimer <dan.magenheimer@oracle.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>