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>
diff --git a/include/trace/events/compaction.h b/include/trace/events/compaction.h
index a43000d7..c92d1e1 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