[Devel] [PATCH RHEL7 COMMIT] ms/mm, compaction: ignore pageblock skip when manually invoking compaction

[Konstantin Khorenko]

The commit is pushed to "branch-rh7-3.10.0-693.11.6.vz7.42.x-ovz" and will appear at https://src.openvz.org/scm/ovz/vzkernel.git
after rh7-3.10.0-693.11.6.vz7.42.4
------>
commit 57ddbd7a8d9361cdd4a384efdbfb4e9f2e7bd1cf
Author: David Rientjes <rientjes at google.com>
Date:   Wed Jan 31 18:21:57 2018 +0300

    ms/mm, compaction: ignore pageblock skip when manually invoking compaction
    
    The cached pageblock hint should be ignored when triggering compaction
    through /proc/sys/vm/compact_memory so all eligible memory is isolated.
    Manually invoking compaction is known to be expensive, there's no need
    to skip pageblocks based on heuristics (mainly for debugging).
    
    Signed-off-by: David Rientjes <rientjes at google.com>
    Acked-by: Mel Gorman <mgorman at suse.de>
    Cc: Rik van Riel <riel at redhat.com>
    Signed-off-by: Andrew Morton <akpm at linux-foundation.org>
    Signed-off-by: Linus Torvalds <torvalds at linux-foundation.org>
    (cherry picked from commit 91ca9186484809c57303b33778d841cc28f696ed)
    Signed-off-by: Andrey Ryabinin <aryabinin at virtuozzo.com>
---
 mm/compaction.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/mm/compaction.c b/mm/compaction.c
index 9f2abe03d1aa..ee0c1e4aecd7 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -1194,6 +1194,7 @@ static void compact_node(int nid)
 	struct compact_control cc = {
 		.order = -1,
 		.sync = true,
+		.ignore_skip_hint = true,
 	};
 
 	__compact_pgdat(NODE_DATA(nid), &cc);