public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Arjan van de Ven <arjan@linux.intel.com>
To: linux-kernel <linux-kernel@vger.kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>, xiaoguangrong@cn.fujitsu.com
Subject: [PATCH] tracing: Make timer tracing actually useful
Date: Wed, 18 Aug 2010 15:33:13 -0700	[thread overview]
Message-ID: <4C6C5FA9.3000405@linux.intel.com> (raw)

[-- Attachment #1: Type: text/plain, Size: 2301 bytes --]



 From fe9633af11395d339880417439a1931bb9e7e493 Mon Sep 17 00:00:00 2001
From: Arjan van de Ven <arjan@linux.intel.com>
Date: Wed, 18 Aug 2010 15:28:59 -0400
Subject: [PATCH] tracing: Make timer tracing actually useful

PowerTOP would like to be able to trace timers.
Unfortunately, the current timer tracing is not very useful, the actual
timer function is not recorded in the trace at the start of timer execution.

Although this is recorded for timer "start" time (when it gets armed), this
is not useful; most timers get started early, and a tracer like PowerTOP
will never see this event, but will only see the actual running of the 
timer.

This patch just adds the function to the timer tracing; I've verified with
PowerTOP that now it can get useful information about timers.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
---
  include/trace/events/timer.h |    8 ++++++--
  1 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/include/trace/events/timer.h b/include/trace/events/timer.h
index c624126..94511c8 100644
--- a/include/trace/events/timer.h
+++ b/include/trace/events/timer.h
@@ -81,14 +81,16 @@ TRACE_EVENT(timer_expire_entry,
      TP_STRUCT__entry(
          __field( void *,    timer    )
          __field( unsigned long,    now    )
+        __field( void *,    function    )
      ),

      TP_fast_assign(
          __entry->timer        = timer;
          __entry->now        = jiffies;
+        __entry->function    = timer->function;
      ),

-    TP_printk("timer=%p now=%lu", __entry->timer, __entry->now)
+    TP_printk("timer=%p function=%pf now=%lu", __entry->timer, 
__entry->function,__entry->now)
  );

  /**
@@ -200,14 +202,16 @@ TRACE_EVENT(hrtimer_expire_entry,
      TP_STRUCT__entry(
          __field( void *,    hrtimer    )
          __field( s64,        now    )
+        __field( void *,    function    )
      ),

      TP_fast_assign(
          __entry->hrtimer    = hrtimer;
          __entry->now        = now->tv64;
+        __entry->function    = hrtimer->function;
      ),

-    TP_printk("hrtimer=%p now=%llu", __entry->hrtimer,
+    TP_printk("hrtimer=%p function=%pf now=%llu", __entry->hrtimer, 
__entry->function,
            (unsigned long long)ktime_to_ns((ktime_t) { .tv64 = 
__entry->now }))
   );

-- 
1.6.1.3


[-- Attachment #2: 0001-tracing-Make-timer-tracing-actually-useful.patch --]
[-- Type: text/plain, Size: 2099 bytes --]

>From fe9633af11395d339880417439a1931bb9e7e493 Mon Sep 17 00:00:00 2001
From: Arjan van de Ven <arjan@linux.intel.com>
Date: Wed, 18 Aug 2010 15:28:59 -0400
Subject: [PATCH] tracing: Make timer tracing actually useful

PowerTOP would like to be able to trace timers.
Unfortunately, the current timer tracing is not very useful, the actual
timer function is not recorded in the trace at the start of timer execution.

Although this is recorded for timer "start" time (when it gets armed), this
is not useful; most timers get started early, and a tracer like PowerTOP
will never see this event, but will only see the actual running of the timer.

This patch just adds the function to the timer tracing; I've verified with
PowerTOP that now it can get useful information about timers.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
---
 include/trace/events/timer.h |    8 ++++++--
 1 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/include/trace/events/timer.h b/include/trace/events/timer.h
index c624126..94511c8 100644
--- a/include/trace/events/timer.h
+++ b/include/trace/events/timer.h
@@ -81,14 +81,16 @@ TRACE_EVENT(timer_expire_entry,
 	TP_STRUCT__entry(
 		__field( void *,	timer	)
 		__field( unsigned long,	now	)
+		__field( void *,	function	)
 	),
 
 	TP_fast_assign(
 		__entry->timer		= timer;
 		__entry->now		= jiffies;
+		__entry->function	= timer->function;
 	),
 
-	TP_printk("timer=%p now=%lu", __entry->timer, __entry->now)
+	TP_printk("timer=%p function=%pf now=%lu", __entry->timer, __entry->function,__entry->now)
 );
 
 /**
@@ -200,14 +202,16 @@ TRACE_EVENT(hrtimer_expire_entry,
 	TP_STRUCT__entry(
 		__field( void *,	hrtimer	)
 		__field( s64,		now	)
+		__field( void *,	function	)
 	),
 
 	TP_fast_assign(
 		__entry->hrtimer	= hrtimer;
 		__entry->now		= now->tv64;
+		__entry->function	= hrtimer->function;
 	),
 
-	TP_printk("hrtimer=%p now=%llu", __entry->hrtimer,
+	TP_printk("hrtimer=%p function=%pf now=%llu", __entry->hrtimer, __entry->function,
 		  (unsigned long long)ktime_to_ns((ktime_t) { .tv64 = __entry->now }))
  );
 
-- 
1.6.1.3


             reply	other threads:[~2010-08-18 22:33 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-08-18 22:33 Arjan van de Ven [this message]
2010-08-19 11:25 ` [tip:perf/urgent] tracing: Fix timer tracing tip-bot for Arjan van de Ven

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=4C6C5FA9.3000405@linux.intel.com \
    --to=arjan@linux.intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@elte.hu \
    --cc=xiaoguangrong@cn.fujitsu.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox