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author | Vlastimil Babka <vbabka@suse.cz> | 2015-11-06 05:48:02 +0300 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-11-06 06:34:48 +0300 |
commit | 2d1e10412c2388ff9b6afc60536eaa195a419289 (patch) | |
tree | b1a4d9b145a9c4442e51141b9fa17d25d8fa90fb /mm/compaction.c | |
parent | 1743d0506003f7db0602d120ecf63e2747af0d72 (diff) | |
download | linux-2d1e10412c2388ff9b6afc60536eaa195a419289.tar.xz |
mm, compaction: distinguish contended status in tracepoints
Compaction returns prematurely with COMPACT_PARTIAL when contended or has
fatal signal pending. This is ok for the callers, but might be misleading
in the traces, as the usual reason to return COMPACT_PARTIAL is that we
think the allocation should succeed. After this patch we distinguish the
premature ending condition in the mm_compaction_finished and
mm_compaction_end tracepoints.
The contended status covers the following reasons:
- lock contention or need_resched() detected in async compaction
- fatal signal pending
- too many pages isolated in the zone (only for async compaction)
Further distinguishing the exact reason seems unnecessary for now.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/compaction.c')
-rw-r--r-- | mm/compaction.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/mm/compaction.c b/mm/compaction.c index a5849c442a57..de3e1e71cd9f 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -1202,7 +1202,7 @@ static int __compact_finished(struct zone *zone, struct compact_control *cc, unsigned long watermark; if (cc->contended || fatal_signal_pending(current)) - return COMPACT_PARTIAL; + return COMPACT_CONTENDED; /* Compaction run completes if the migrate and free scanner meet */ if (compact_scanners_met(cc)) { @@ -1393,7 +1393,7 @@ static int compact_zone(struct zone *zone, struct compact_control *cc) switch (isolate_migratepages(zone, cc)) { case ISOLATE_ABORT: - ret = COMPACT_PARTIAL; + ret = COMPACT_CONTENDED; putback_movable_pages(&cc->migratepages); cc->nr_migratepages = 0; goto out; @@ -1424,7 +1424,7 @@ static int compact_zone(struct zone *zone, struct compact_control *cc) * and we want compact_finished() to detect it */ if (err == -ENOMEM && !compact_scanners_met(cc)) { - ret = COMPACT_PARTIAL; + ret = COMPACT_CONTENDED; goto out; } } @@ -1477,6 +1477,9 @@ out: trace_mm_compaction_end(start_pfn, cc->migrate_pfn, cc->free_pfn, end_pfn, sync, ret); + if (ret == COMPACT_CONTENDED) + ret = COMPACT_PARTIAL; + return ret; } |