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* [PATCH] perf_event: initialize data.period in perf_swevent_hrtimer()
@ 2009-12-01  9:30 Xiao Guangrong
  2009-12-01  9:37 ` Peter Zijlstra
  2009-12-01 10:21 ` [tip:perf/core] perf_event: Initialize " tip-bot for Xiao Guangrong
  0 siblings, 2 replies; 3+ messages in thread
From: Xiao Guangrong @ 2009-12-01  9:30 UTC (permalink / raw)
  To: Ingo Molnar; +Cc: Peter Zijlstra, Frederic Weisbecker, LKML

In current code in perf_swevent_hrtimer(), data.period is not initialized,
The result is obvious wrong:

# ./perf record -f -e cpu-clock make
# ./perf report
# Samples: 1740
#
# Overhead   Command                                   ...... 
# ........  ........  ..........................................
#
   1025422183050275328.00%        sh  libc-2.9.90.so ...        
   1025422183050275328.00%      perl  libperl.so     ...        
   1025422168240043264.00%      perl  [kernel]       ...         
   1025422030011210752.00%      perl  [kernel]       ...

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
---
 kernel/perf_event.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 0b9ca2d..040ee51 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -4010,6 +4010,7 @@ static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer)
 	event->pmu->read(event);
 
 	data.addr = 0;
+	data.period = event->hw.last_period;
 	regs = get_irq_regs();
 	/*
 	 * In case we exclude kernel IPs or are somehow not in interrupt
-- 
1.6.1.2



^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH] perf_event: initialize data.period in perf_swevent_hrtimer()
  2009-12-01  9:30 [PATCH] perf_event: initialize data.period in perf_swevent_hrtimer() Xiao Guangrong
@ 2009-12-01  9:37 ` Peter Zijlstra
  2009-12-01 10:21 ` [tip:perf/core] perf_event: Initialize " tip-bot for Xiao Guangrong
  1 sibling, 0 replies; 3+ messages in thread
From: Peter Zijlstra @ 2009-12-01  9:37 UTC (permalink / raw)
  To: Xiao Guangrong; +Cc: Ingo Molnar, Frederic Weisbecker, LKML

On Tue, 2009-12-01 at 17:30 +0800, Xiao Guangrong wrote:
> In current code in perf_swevent_hrtimer(), data.period is not initialized,

Ah, very nice catch.

Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>

> Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
> ---
>  kernel/perf_event.c |    1 +
>  1 files changed, 1 insertions(+), 0 deletions(-)
> 
> diff --git a/kernel/perf_event.c b/kernel/perf_event.c
> index 0b9ca2d..040ee51 100644
> --- a/kernel/perf_event.c
> +++ b/kernel/perf_event.c
> @@ -4010,6 +4010,7 @@ static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer)
>  	event->pmu->read(event);
>  
>  	data.addr = 0;
> +	data.period = event->hw.last_period;
>  	regs = get_irq_regs();
>  	/*
>  	 * In case we exclude kernel IPs or are somehow not in interrupt



^ permalink raw reply	[flat|nested] 3+ messages in thread

* [tip:perf/core] perf_event: Initialize data.period in perf_swevent_hrtimer()
  2009-12-01  9:30 [PATCH] perf_event: initialize data.period in perf_swevent_hrtimer() Xiao Guangrong
  2009-12-01  9:37 ` Peter Zijlstra
@ 2009-12-01 10:21 ` tip-bot for Xiao Guangrong
  1 sibling, 0 replies; 3+ messages in thread
From: tip-bot for Xiao Guangrong @ 2009-12-01 10:21 UTC (permalink / raw)
  To: linux-tip-commits
  Cc: linux-kernel, hpa, mingo, peterz, xiaoguangrong, fweisbec, stable,
	tglx, mingo

Commit-ID:  59d069eb5ae9b033ed1c124c92e1532c4a958991
Gitweb:     http://git.kernel.org/tip/59d069eb5ae9b033ed1c124c92e1532c4a958991
Author:     Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
AuthorDate: Tue, 1 Dec 2009 17:30:08 +0800
Committer:  Ingo Molnar <mingo@elte.hu>
CommitDate: Tue, 1 Dec 2009 11:19:07 +0100

perf_event: Initialize data.period in perf_swevent_hrtimer()

In current code in perf_swevent_hrtimer(), data.period is not
initialized, The result is obvious wrong:

 # ./perf record -f -e cpu-clock make
 # ./perf report
 # Samples: 1740
 #
 # Overhead   Command                                   ......
 # ........  ........  ..........................................
 #
   1025422183050275328.00%        sh  libc-2.9.90.so ...
   1025422183050275328.00%      perl  libperl.so     ...
   1025422168240043264.00%      perl  [kernel]       ...
   1025422030011210752.00%      perl  [kernel]       ...

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: <stable@kernel.org>
LKML-Reference: <4B14E220.2050107@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 kernel/perf_event.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 0b9ca2d..040ee51 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -4010,6 +4010,7 @@ static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer)
 	event->pmu->read(event);
 
 	data.addr = 0;
+	data.period = event->hw.last_period;
 	regs = get_irq_regs();
 	/*
 	 * In case we exclude kernel IPs or are somehow not in interrupt

^ permalink raw reply related	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2009-12-01 10:22 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
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2009-12-01  9:30 [PATCH] perf_event: initialize data.period in perf_swevent_hrtimer() Xiao Guangrong
2009-12-01  9:37 ` Peter Zijlstra
2009-12-01 10:21 ` [tip:perf/core] perf_event: Initialize " tip-bot for Xiao Guangrong

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