From 52c8f6a5aeb0bdd396849ecaa72d96f8175528f5 Mon Sep 17 00:00:00 2001
From: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
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 <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
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 d0c613476620..aece1346ceb7 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 5a9883614d99..442f1298f9a7 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;
}
--
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