From 52c8f6a5aeb0bdd396849ecaa72d96f8175528f5 Mon Sep 17 00:00:00 2001 From: KOSAKI Motohiro Date: Tue, 12 Nov 2013 15:08:19 -0800 Subject: [PATCH] mm: get rid of unnecessary overhead of trace_mm_page_alloc_extfrag() In general, every tracepoint should be zero overhead if it is disabled. However, trace_mm_page_alloc_extfrag() is one of exception. It evaluate "new_type == start_migratetype" even if tracepoint is disabled. However, the code can be moved into tracepoint's TP_fast_assign() and TP_fast_assign exist exactly such purpose. This patch does it. Signed-off-by: KOSAKI Motohiro Acked-by: Mel Gorman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/trace/events/kmem.h | 10 ++++------ mm/page_alloc.c | 5 ++--- 2 files changed, 6 insertions(+), 9 deletions(-) diff --git a/include/trace/events/kmem.h b/include/trace/events/kmem.h index d0c6134..aece134 100644 --- a/include/trace/events/kmem.h +++ b/include/trace/events/kmem.h @@ -267,14 +267,12 @@ DEFINE_EVENT_PRINT(mm_page, mm_page_pcpu_drain, TRACE_EVENT(mm_page_alloc_extfrag, TP_PROTO(struct page *page, - int alloc_order, int fallback_order, - int alloc_migratetype, int fallback_migratetype, - int change_ownership), + int alloc_order, int fallback_order, + int alloc_migratetype, int fallback_migratetype, int new_migratetype), TP_ARGS(page, alloc_order, fallback_order, - alloc_migratetype, fallback_migratetype, - change_ownership), + alloc_migratetype, fallback_migratetype, new_migratetype), TP_STRUCT__entry( __field( struct page *, page ) @@ -291,7 +289,7 @@ TRACE_EVENT(mm_page_alloc_extfrag, __entry->fallback_order = fallback_order; __entry->alloc_migratetype = alloc_migratetype; __entry->fallback_migratetype = fallback_migratetype; - __entry->change_ownership = change_ownership; + __entry->change_ownership = (new_migratetype == alloc_migratetype); ), TP_printk("page=%p pfn=%lu alloc_order=%d fallback_order=%d pageblock_order=%d alloc_migratetype=%d fallback_migratetype=%d fragmenting=%d change_ownership=%d", diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 5a98836..442f129 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1103,9 +1103,8 @@ __rmqueue_fallback(struct zone *zone, int order, int start_migratetype) is_migrate_cma(migratetype) ? migratetype : start_migratetype); - trace_mm_page_alloc_extfrag(page, order, - current_order, start_migratetype, migratetype, - new_type == start_migratetype); + trace_mm_page_alloc_extfrag(page, order, current_order, + start_migratetype, migratetype, new_type); return page; } -- 2.7.4