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@google.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/compaction.c b/mm/compaction.c
index 918577595ea8695298cd21ecab7acaca35b1eb92..37b3799d948ca4dd7eb9155e843ad3be18fc9542 100644 (file)
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -1186,6 +1186,7 @@ static void compact_node(int nid)
        struct compact_control cc = {
                .order = -1,
                .sync = true,
+               .ignore_skip_hint = true,
        };
 
        __compact_pgdat(NODE_DATA(nid), &cc);