Re: [PATCH 08/10] perf tools: Add --raw-trace option

From: Namhyung Kim <namhyung@kernel.org>
To: Jiri Olsa <jolsa@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>,
	Ingo Molnar <mingo@kernel.org>,
	Peter Zijlstra <peterz@infradead.org>,
	LKML <linux-kernel@vger.kernel.org>,
	David Ahern <dsahern@gmail.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	Frederic Weisbecker <fweisbec@gmail.com>,
	Andi Kleen <andi@firstfloor.org>, Wang Nan <wangnan0@huawei.com>
Subject: Re: [PATCH 08/10] perf tools: Add --raw-trace option
Date: Wed, 23 Dec 2015 01:19:17 +0900	[thread overview]
Message-ID: <20151222161917.GC4508@danjae.kornet> (raw)
In-Reply-To: <20151222065712.GB13404@krava.brq.redhat.com>

On Tue, Dec 22, 2015 at 07:57:12AM +0100, Jiri Olsa wrote:
> On Mon, Dec 21, 2015 at 05:44:41PM +0900, Namhyung Kim wrote:
> 
> SNIP
> 
> > > 
> > > I think the default is good with the 'trace' sort key as it is now:
> > > 
> > > 	$ ./perf report -s trace 
> > > 	  27.01%  offlineimap:17701 [120] S ==> swapper/1:0 [120]
> > > 	  27.00%  swapper/1:0 [120] R ==> offlineimap:17701 [120]
> > > 
> > > 
> > > But for '--raw-trace' option rather than displaying fields in the '=' notation:
> > > 
> > > 	$ ./perf report -s trace --raw-trace
> > > 	  27.01%   prev_comm=offlineimap prev_pid=17701 prev_prio=120 prev_state=1 next_comm=swapper/1 next_pid=0 next_prio=120
> > > 	  27.00%   prev_comm=swapper/1 prev_pid=0 prev_prio=120 prev_state=0 next_comm=offlineimap next_pid=17701 next_prio=120
> > > 
> > > 
> > > it would be more readable to register all available columns as is possible to do now with:
> > > 
> > > 	$ ./perf report -s prev_comm,prev_pid,prev_prio,prev_state,next_comm,next_pid,next_prio
> > > 	Overhead         prev_comm    prev_pid   prev_prio          prev_state         next_comm    next_pid   next_prio
> > > 	  27.01%       offlineimap       17701         120                   1         swapper/1           0         120
> > > 	  27.00%         swapper/1           0         120                   0       offlineimap       17701         120
> > > 
> > > 
> > > it would be default output for 'perf report -s trace --raw-trace' command
> > > 
> > > how about that?
> > 
> > 
> > I agree with the latter is much more readable.  But the dynamic sort
> > keys are event specific while 'trace' is generic.  So if there are
> > more than one events, dynamic sort keys should be generated for each
> > event and they'll show "N/A" for other events.
> 
> I see.. haven't realized that, maybe we should add
> columns based in the hists object.. but I guess
> that's out of scope of this patchset ;-)

Right.

On a second thought, I can make it skip dynamic fields if they're for
other event.  Then we don't need to maintain per-event sort keys IMHO.

> 
> > 
> > Also I don't like the --raw-trace option affects number of sort keys.
> > Maybe it'd be better adding 'EVENT.*' dynamic sort key for your case?
> 
> that's good workaround, thanks

With above trick, I think I can add all dynamic fields automatically
as default sort key when --raw-trace is given as you said.  Will try.

Thanks,
Namhyung