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Date:   Wed, 3 Mar 2021 18:17:01 +0200
From:   Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     Petr Mladek <pmladek@suse.com>, Stephen Boyd <swboyd@chromium.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel@vger.kernel.org, Jiri Olsa <jolsa@kernel.org>,
        Alexei Starovoitov <ast@kernel.org>,
        Jessica Yu <jeyu@kernel.org>,
        Evan Green <evgreen@chromium.org>,
        Hsin-Yi Wang <hsinyi@chromium.org>,
        Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
        Rasmus Villemoes <linux@rasmusvillemoes.dk>,
        linux-doc@vger.kernel.org
Subject: Re: [PATCH 5/7] printk: Make %pS and friends print module build ID
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References: <20210301174749.1269154-1-swboyd@chromium.org>
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On Wed, Mar 03, 2021 at 10:00:12AM -0500, Steven Rostedt wrote:
> On Wed, 3 Mar 2021 11:25:58 +0100
> Petr Mladek <pmladek@suse.com> wrote:
> 
> > Alternative solution would be to minimize the information, for
> > example, by printing only the modules that appear in the backtrace.
> > But this might be complicated to implement.
> 
> It could be a list after the backtrace perhaps, and not part of the
> "modules linked in"?
> 
> But then you need a generic way of capturing those modules in the backtrace
> that works for every architecture.

> Honestly, I don't even know what a buildid is, and it is totally useless
> information for myself. What exactly is it used for?

Dunno Stephen's motivation, but build ID is very useful when you do tracing,
then based on ID the decoders can know what exactly was the layout of the
binary and list of (exported) functions, etc.

At least that was my (shallow) experience with perf last time I have tried it.

-- 
With Best Regards,
Andy Shevchenko