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Re: [PATCH] tracing: Only benchmark the time tracepoints take if tracing is on

From Steven Rostedt <rostedt@goodmis.org>
Newsgroups linux.kernel
Subject Re: [PATCH] tracing: Only benchmark the time tracepoints take if tracing is on
Date 2015-10-28 03:30 +0100
Message-ID <qooEV-4Wx-3@gated-at.bofh.it> (permalink)
References <qobom-56u-5@gated-at.bofh.it>
Organization linux.* mail to news gateway

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On Tue, 27 Oct 2015 20:12:13 +0800
Chunyan Zhang <zhang.chunyan@linaro.org> wrote:

> There's no need to record the time tracepoints take when tracing is off.
> This is because:
> 1) We cannot see these records since ring_buffer record is off at that
> moment.
> 2) If tracing is off and benchmark tracepoint is enabled, the time
> tracepoint takes is fewer than the same situation when tracing is on,
> since the tracepoints need to be wrote into ring_buffer, it would
> take more time. If turn on tracing at this moment, the average and
> standard deviation cannot exactly present the time that tracepoints
> take to write data into ring_buffer.
> 

Thanks! I'll add this when I get back from traveling.

-- Steve


> Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
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[PATCH] tracing: Only benchmark the time tracepoints take if tracing is on Chunyan Zhang <zhang.chunyan@linaro.org> - 2015-10-27 13:20 +0100
  Re: [PATCH] tracing: Only benchmark the time tracepoints take if  tracing is on Steven Rostedt <rostedt@goodmis.org> - 2015-10-28 03:30 +0100

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