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Date:   Sun, 17 May 2020 09:34:52 +0000
From:   Changbin Du <changbin.du@gmail.com>
To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     Changbin Du <changbin.du@gmail.com>,
        Ingo Molnar <mingo@redhat.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] tracing: do not create option file latency-format
Message-ID: <20200517093451.uvm557aatmll62fo@mail.google.com>
References: <20200516161017.155791-1-changbin.du@gmail.com>
 <20200516131521.02005210@oasis.local.home>
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Hi Steven,

On Sat, May 16, 2020 at 01:15:21PM -0400, Steven Rostedt wrote:
> On Sun, 17 May 2020 00:10:17 +0800
> Changbin Du <changbin.du@gmail.com> wrote:
> 
> > The flag LATENCY_FMT actually is usually set by latency tracers internally.
> > So I think we should not export it to userspace. This patch removes the
> > option file 'latency-format' but keep the flag defined as usual.
> > 
> > Signed-off-by: Changbin Du <changbin.du@gmail.com>
> > ---
> 
> Sorry, I actually do sometimes use that option for things other than
> latency tracers. So NACK.
>
May I know which tracer use this option as well? As far as I know,
besides latency tracers, the fgraph tracer also uses it.

I think 'irq-info' and 'latency-format' is somewhat overlaps. So
my thought is:
 1) function and function graph tracers should use irq-info.
 2) latency tracers should set latency-format.

I am not quite sure whether this is a good idea. :)

> -- Steve

-- 
Cheers,
Changbin Du