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Date: Tue, 8 Sep 2026 18:04:55 -0300
From: Arnaldo Carvalho de Melo <acme@kernel.org>
To: Ian Rogers <irogers@google.com>
Cc: Namhyung Kim <namhyung@kernel.org>, Jiri Olsa <jolsa@kernel.org>,
	Adrian Hunter <adrian.hunter@intel.com>,
	James Clark <james.clark@linaro.org>,
	Peter Zijlstra <peterz@infradead.org>,
	Ingo Molnar <mingo@kernel.org>, LKML <linux-kernel@vger.kernel.org>,
	linux-perf-users@vger.kernel.org,
	Steven Rostedt <rostedt@goodmis.org>,
	Masami Hiramatsu <mhiramat@kernel.org>
Subject: Re: [PATCH v2] perf ftrace latency: Do not read trace files when BPF
 is used
Message-ID: <aqB4d6H-qnPHKlSA@x2>
References: <20260831063938.756610-1-namhyung@kernel.org>
 <CAP-5=fWenUPGqNjy6CdzEnti8czpJTg14w=FTbDrTrHb9APRAw@mail.gmail.com>
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On Fri, Sep 04, 2026 at 10:36:08AM -0700, Ian Rogers wrote:
> On Sun, Aug 30, 2026 at 11:39 PM Namhyung Kim <namhyung@kernel.org> wrote:
> >
> > I've realized that it didn't set up the tracing files when BPF is used
> > so poll() just returns immediately.  It ends up with calling poll()
> > unnecessarily in a loop.
> >
> > BPF still needs the loop to wait for the target process exiting or a
> > signal from users.  Let's use a semaphore instead.
> >
> > Suggested-by: Ian Rogers <irogers@google.com>
> > Cc: Steven Rostedt <rostedt@goodmis.org>
> > Cc: Masami Hiramatsu <mhiramat@kernel.org>
> > Signed-off-by: Namhyung Kim <namhyung@kernel.org>
> 
> Reviewed-by: Ian Rogers <irogers@google.com>

Thanks, applied to perf-tools-next, for v7.4.

- Arnaldo