From: Mel Gorman Date: Mon, 7 Oct 2013 10:28:50 +0000 (+0100) Subject: mm: numa: Do not migrate or account for hinting faults on the zero page X-Git-Tag: omap-for-v3.13/fixes-for-merge-window-take2~40^2~78 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a1a46184e34cfd0764f06a54870defa052b0a094;p=pandora-kernel.git mm: numa: Do not migrate or account for hinting faults on the zero page The zero page is not replicated between nodes and is often shared between processes. The data is read-only and likely to be cached in local CPUs if heavily accessed meaning that the remote memory access cost is less of a concern. This patch prevents trapping faults on the zero pages. For tasks using the zero page this will reduce the number of PTE updates, TLB flushes and hinting faults. Signed-off-by: Mel Gorman Reviewed-by: Rik van Riel Cc: Andrea Arcangeli Cc: Johannes Weiner Cc: Srikar Dronamraju [ Correct use of is_huge_zero_page] Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/1381141781-10992-13-git-send-email-mgorman@suse.de Signed-off-by: Ingo Molnar --- Reading git-diff-tree failed