mm/compaction: add tracepoint to observe behaviour of compaction defer

Compaction deferring logic is heavy hammer that block the way to the
compaction.  It doesn't consider overall system state, so it could prevent
user from doing compaction falsely.  In other words, even if system has
enough range of memory to compact, compaction would be skipped due to
compaction deferring logic.  This patch add new tracepoint to understand
work of deferring logic.  This will also help to check compaction success
and fail.

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@suse.de>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Joonsoo Kim 2015-02-11 15:27:09 -08:00 committed by Linus Torvalds
parent 837d026d56
commit 24e2716f63
3 changed files with 132 additions and 60 deletions

View file

@ -238,6 +238,62 @@ DEFINE_EVENT(mm_compaction_suitable_template, mm_compaction_suitable,
TP_ARGS(zone, order, ret)
);
#ifdef CONFIG_COMPACTION
DECLARE_EVENT_CLASS(mm_compaction_defer_template,
TP_PROTO(struct zone *zone, int order),
TP_ARGS(zone, order),
TP_STRUCT__entry(
__field(int, nid)
__field(char *, name)
__field(int, order)
__field(unsigned int, considered)
__field(unsigned int, defer_shift)
__field(int, order_failed)
),
TP_fast_assign(
__entry->nid = zone_to_nid(zone);
__entry->name = (char *)zone->name;
__entry->order = order;
__entry->considered = zone->compact_considered;
__entry->defer_shift = zone->compact_defer_shift;
__entry->order_failed = zone->compact_order_failed;
),
TP_printk("node=%d zone=%-8s order=%d order_failed=%d consider=%u limit=%lu",
__entry->nid,
__entry->name,
__entry->order,
__entry->order_failed,
__entry->considered,
1UL << __entry->defer_shift)
);
DEFINE_EVENT(mm_compaction_defer_template, mm_compaction_deferred,
TP_PROTO(struct zone *zone, int order),
TP_ARGS(zone, order)
);
DEFINE_EVENT(mm_compaction_defer_template, mm_compaction_defer_compaction,
TP_PROTO(struct zone *zone, int order),
TP_ARGS(zone, order)
);
DEFINE_EVENT(mm_compaction_defer_template, mm_compaction_defer_reset,
TP_PROTO(struct zone *zone, int order),
TP_ARGS(zone, order)
);
#endif
#endif /* _TRACE_COMPACTION_H */
/* This part must be outside protection */