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

[Steven Rostedt]

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