diff options
| author | Vlastimil Babka | 2015-11-05 18:48:02 -0800 |
|---|---|---|
| committer | Linus Torvalds | 2015-11-05 19:34:48 -0800 |
| commit | 2d1e10412c2388ff9b6afc60536eaa195a419289 (patch) | |
| tree | b1a4d9b145a9c4442e51141b9fa17d25d8fa90fb | |
| parent | 1743d0506003f7db0602d120ecf63e2747af0d72 (diff) | |
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>
| -rw-r--r-- | include/linux/compaction.h | 1 | ||||
| -rw-r--r-- | include/trace/events/compaction.h | 3 | ||||
| -rw-r--r-- | mm/compaction.c | 9 |
3 files changed, 9 insertions, 4 deletions
diff --git a/include/linux/compaction.h b/include/linux/compaction.h index f14ba989092f..4cd4ddf64cc7 100644 --- a/include/linux/compaction.h +++ b/include/linux/compaction.h @@ -15,6 +15,7 @@ /* For more detailed tracepoint output */ #define COMPACT_NO_SUITABLE_PAGE 5 #define COMPACT_NOT_SUITABLE_ZONE 6 +#define COMPACT_CONTENDED 7 /* When adding new states, please adjust include/trace/events/compaction.h */ /* Used to signal whether compaction detected need_sched() or lock contention */ diff --git a/include/trace/events/compaction.h b/include/trace/events/compaction.h index a43000d76688..c92d1e1cbad9 100644 --- a/include/trace/events/compaction.h +++ b/include/trace/events/compaction.h @@ -16,7 +16,8 @@ EM( COMPACT_PARTIAL, "partial") \ EM( COMPACT_COMPLETE, "complete") \ EM( COMPACT_NO_SUITABLE_PAGE, "no_suitable_page") \ - EMe(COMPACT_NOT_SUITABLE_ZONE, "not_suitable_zone") + EM( COMPACT_NOT_SUITABLE_ZONE, "not_suitable_zone") \ + EMe(COMPACT_CONTENDED, "contended") #ifdef CONFIG_ZONE_DMA #define IFDEF_ZONE_DMA(X) X 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; } |