diff options
author | Hugh Dickins <hughd@google.com> | 2016-07-28 15:48:41 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-07-28 16:07:41 -0700 |
commit | 1d2047fefa20e49072f6a37a7f71544e8cace529 (patch) | |
tree | 0da9cd7348ee67586ea430e09190be88970923c3 | |
parent | 7c7fd82556c61113b6327c9696b347a82b215072 (diff) |
mm, compaction: don't isolate PageWriteback pages in MIGRATE_SYNC_LIGHT mode
At present MIGRATE_SYNC_LIGHT is allowing __isolate_lru_page() to
isolate a PageWriteback page, which __unmap_and_move() then rejects with
-EBUSY: of course the writeback might complete in between, but that's
not what we usually expect, so probably better not to isolate it.
When tested by stress-highalloc from mmtests, this has reduced the
number of page migrate failures by 60-70%.
Link: http://lkml.kernel.org/r/20160721073614.24395-2-vbabka@suse.cz
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r-- | mm/compaction.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/compaction.c b/mm/compaction.c index e5995f38d677..fee1118c8b94 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -1200,7 +1200,7 @@ static isolate_migrate_t isolate_migratepages(struct zone *zone, struct page *page; const isolate_mode_t isolate_mode = (sysctl_compact_unevictable_allowed ? ISOLATE_UNEVICTABLE : 0) | - (cc->mode == MIGRATE_ASYNC ? ISOLATE_ASYNC_MIGRATE : 0); + (cc->mode != MIGRATE_SYNC ? ISOLATE_ASYNC_MIGRATE : 0); /* * Start at where we last stopped, or beginning of the zone as |