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Date:   Tue, 25 Jul 2023 17:55:36 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Ze Gao <zegao2021@gmail.com>, Ingo Molnar <mingo@redhat.com>,
        Namhyung Kim <namhyung@kernel.org>,
        Ian Rogers <irogers@google.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Jiri Olsa <jolsa@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        Adrian Hunter <adrian.hunter@intel.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org,
        linux-trace-kernel@vger.kernel.org, Ze Gao <zegao@tencent.com>
Subject: Re: [RFC PATCH 1/3] sched, tracing: report task state in symbolic
 chars instead
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On Tue, 25 Jul 2023 22:16:03 +0200
Peter Zijlstra <peterz@infradead.org> wrote:

> > Now, because the old tools still do the parsing of this format, we can
> > add a new field called prev_state_char that will give you this. Now to
> > save space, we should change prev_state to int (can't make it short as
> > there's that test for "+" which does sometimes happen). I believe we
> > can make prev_prio and next prio into shorts (and possibly chars!).  
> 
> Or just leave the thing alone?

Sure, but I would like to change the fields to smaller ones just so
that the event wastes less space on the buffer.

-- Steve