diff options
author | Mel Gorman <mel@csn.ul.ie> | 2009-09-21 17:02:44 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-09-22 07:17:34 -0700 |
commit | 0d3d062a6e289e065bd0aa537a6806a1806bf8aa (patch) | |
tree | 9895e9cb48674d072885af3424e1ef145ec81f28 /include | |
parent | e0fff1bd12469c45dab088e353d8882761387bb6 (diff) | |
download | linux-0d3d062a6e289e065bd0aa537a6806a1806bf8aa.tar.bz2 |
tracing, page-allocator: add trace event for page traffic related to the buddy lists
The page allocation trace event reports that a page was successfully
allocated but it does not specify where it came from. When analysing
performance, it can be important to distinguish between pages coming from
the per-cpu allocator and pages coming from the buddy lists as the latter
requires the zone lock to the taken and more data structures to be
examined.
This patch adds a trace event for __rmqueue reporting when a page is being
allocated from the buddy lists. It distinguishes between being called to
refill the per-cpu lists or whether it is a high-order allocation.
Similarly, this patch adds an event to catch when the PCP lists are being
drained a little and pages are going back to the buddy lists.
This is trickier to draw conclusions from but high activity on those
events could explain why there were a large number of cache misses on a
page-allocator-intensive workload. The coalescing and splitting of
buddies involves a lot of writing of page metadata and cache line bounces
not to mention the acquisition of an interrupt-safe lock necessary to
enter this path.
[akpm@linux-foundation.org: fix build]
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Cc: Larry Woodman <lwoodman@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Li Ming Chun <macli@brc.ubc.ca>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include')
-rw-r--r-- | include/trace/events/kmem.h | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/include/trace/events/kmem.h b/include/trace/events/kmem.h index aae16ee17601..eaf46bdd18a5 100644 --- a/include/trace/events/kmem.h +++ b/include/trace/events/kmem.h @@ -299,6 +299,57 @@ TRACE_EVENT(mm_page_alloc, show_gfp_flags(__entry->gfp_flags)) ); +TRACE_EVENT(mm_page_alloc_zone_locked, + + TP_PROTO(struct page *page, unsigned int order, int migratetype), + + TP_ARGS(page, order, migratetype), + + TP_STRUCT__entry( + __field( struct page *, page ) + __field( unsigned int, order ) + __field( int, migratetype ) + ), + + TP_fast_assign( + __entry->page = page; + __entry->order = order; + __entry->migratetype = migratetype; + ), + + TP_printk("page=%p pfn=%lu order=%u migratetype=%d percpu_refill=%d", + __entry->page, + page_to_pfn(__entry->page), + __entry->order, + __entry->migratetype, + __entry->order == 0) +); + +TRACE_EVENT(mm_page_pcpu_drain, + + TP_PROTO(struct page *page, int order, int migratetype), + + TP_ARGS(page, order, migratetype), + + TP_STRUCT__entry( + __field( struct page *, page ) + __field( int, order ) + __field( int, migratetype ) + ), + + TP_fast_assign( + __entry->page = page; + __entry->order = order; + __entry->migratetype = migratetype; + ), + + TP_printk("page=%p pfn=%lu order=%d migratetype=%d", + __entry->page, + page_to_pfn(__entry->page), + __entry->order, + __entry->migratetype) +); + TRACE_EVENT(mm_page_alloc_extfrag, TP_PROTO(struct page *page, |