From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 77CB0C433EF for ; Tue, 16 Nov 2021 13:47:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 58C6A61C4F for ; Tue, 16 Nov 2021 13:47:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236864AbhKPNuw (ORCPT ); Tue, 16 Nov 2021 08:50:52 -0500 Received: from mail.kernel.org ([198.145.29.99]:59698 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236798AbhKPNuu (ORCPT ); Tue, 16 Nov 2021 08:50:50 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id A947761B49; Tue, 16 Nov 2021 13:47:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1637070473; bh=L0/b5A0ZQAlrQCQ9zkoxCpHSFp5715/1sSWroaWRkvk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=LRpkJ6ZTVi2gdfregIDk41LH1kHqUcVLhJPraAw//U+SitZUvNRUS2b8WmEMENKdP kIY+UE5d903gig8jkwavug7MWqDFyYwP1aYdvd1HrHKh7yoLaKXk87jYXRd+k51QjT 4trC61ZTUTSjFgNPLe8J0eZx+EsA0PD7/bHpSF9eZGqD//2ArxbP5pXxx6kUIDA3X2 T9QVtulXtbGZmrI0FgOuv0GM7yzx/oXPWcFpijcVtzVQJcEKIZbFdzRvQSo36NyRRi gDEpBj+u1ch4Fy6ZQoQ1PcD7atLyCR2HnEh/urmFzfB+DCzQcTOgK1IeBUsCR5ZW0M 2mXWYvtPcBlxA== Received: by quaco.ghostprotocols.net (Postfix, from userid 1000) id 4F34E4088E; Tue, 16 Nov 2021 10:47:50 -0300 (-03) Date: Tue, 16 Nov 2021 10:47:50 -0300 From: Arnaldo Carvalho de Melo To: Sohaib Mohamed Cc: rickyman7@gmail.com, irogers@google.com, Peter Zijlstra , Ingo Molnar , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Yury Norov , Andy Shevchenko , Andrew Morton , linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] perf bench: flush stats when pipe it to a file or to tee Message-ID: References: <20211112215313.108823-1-sohaib.amhmd@gmail.com> <20211115224151.odaewu62ltx7smty@pc> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20211115224151.odaewu62ltx7smty@pc> X-Url: http://acmel.wordpress.com Precedence: bulk List-ID: X-Mailing-List: linux-perf-users@vger.kernel.org Em Tue, Nov 16, 2021 at 12:41:51AM +0200, Sohaib Mohamed escreveu: > Hello, Arnaldo > > On Sat, Nov 13, 2021 at 09:18:22AM -0300, Arnaldo Carvalho de Melo wrote: > > Em Sat, Nov 13, 2021 at 09:16:42AM -0300, Arnaldo Carvalho de Melo escreveu: > > > Em Fri, Nov 12, 2021 at 11:53:12PM +0200, Sohaib Mohamed escreveu: > > > > The output of perf bench gets buffered when I pipe it to a file or to > > > > tee, in such a way that I can see it only at the end. > > > > > > Good, now try with 'perf test' :-) > > > > > > Applying, > > > > Humm, take that back, when I almost did it for 'perf test' I used > > setvbuf(), take a look at it so that you don't have to go sprinkling > > fflush() calls and missing some places. > > > > - Arnaldo > > I'm not sure about the meaning of 'perf test' here, Should I write new unit > tests? Try: $ perf test 2>&1 | tee /tmp/bla It uses buffered output, so we see the output in bumps, would be better to use unbuffered. > I found I could invoke this function at the beginning of perf-bench: > setvbuf(stdout, NULL, _IONBF, 0); > This looks to me will resolve the issue for all perf-bench subcommands. > I'm not sure if a good practice... Well, it will achieve what you want, right? Unbuffered output, which I think is desirable. > This probably is version 2 of this patch: Yeah, looks ok. - Arnaldo > > diff --git a/tools/perf/builtin-bench.c b/tools/perf/builtin-bench.c > index d0895162c2ba..a0b812cde1ee 100644 > --- a/tools/perf/builtin-bench.c > +++ b/tools/perf/builtin-bench.c > @@ -226,7 +226,6 @@ static void run_collection(struct collection *coll) > if (!bench->fn) > break; > printf("# Running %s/%s benchmark...\n", coll->name, bench->name); > - fflush(stdout); > > argv[1] = bench->name; > run_bench(coll->name, bench->name, bench->fn, 1, argv); > @@ -247,6 +246,8 @@ int cmd_bench(int argc, const char **argv) > struct collection *coll; > int ret = 0; > > + setvbuf(stdout, NULL, _IONBF, 0); > + > if (argc < 2) { > /* No collection specified. */ > print_usage(); > @@ -300,7 +301,6 @@ int cmd_bench(int argc, const char **argv) > > if (bench_format == BENCH_FORMAT_DEFAULT) > printf("# Running '%s/%s' benchmark:\n", coll->name, bench->name); > - fflush(stdout); > ret = run_bench(coll->name, bench->name, bench->fn, argc-1, argv+1); > goto end; > } > > > > Thanks, > - Sohaib > > > > > > - Arnaldo > > > > > > > E.g. > > > > $ perf bench internals synthesize -t > > > > < output comes out fine after each test run > > > > > > > > > $ perf bench internals synthesize -t | tee file.txt > > > > < output comes out only at the end of all tests > > > > > > > > > See, also: > > > > $ perf bench mem all | tee file.txt > > > > $ perf bench sched all | tee file.txt > > > > $ perf bench internals all -t | tee file.txt > > > > $ perf bench internals all | tee file.txt > > > > > > > > Suggested-by: Riccardo Mancini > > > > Signed-off-by: Sohaib Mohamed > > > > --- > > > > tools/perf/bench/find-bit-bench.c | 1 + > > > > tools/perf/bench/synthesize.c | 2 ++ > > > > 2 files changed, 3 insertions(+) > > > > > > > > diff --git a/tools/perf/bench/find-bit-bench.c b/tools/perf/bench/find-bit-bench.c > > > > index 22b5cfe97023..39fb4184fbcb 100644 > > > > --- a/tools/perf/bench/find-bit-bench.c > > > > +++ b/tools/perf/bench/find-bit-bench.c > > > > @@ -113,6 +113,7 @@ static int do_for_each_set_bit(unsigned int num_bits) > > > > > > > > if (use_of_val == accumulator) /* Try to avoid compiler tricks. */ > > > > printf("\n"); > > > > + fflush(stdout); > > > > } > > > > bitmap_free(to_test); > > > > return 0; > > > > diff --git a/tools/perf/bench/synthesize.c b/tools/perf/bench/synthesize.c > > > > index 7401ebbac100..d21d311df61b 100644 > > > > --- a/tools/perf/bench/synthesize.c > > > > +++ b/tools/perf/bench/synthesize.c > > > > @@ -92,6 +92,7 @@ static int do_run_single_threaded(struct perf_session *session, > > > > update_stats(&event_stats, atomic_read(&event_count)); > > > > } > > > > > > > > + fflush(stdout); > > > > time_average = avg_stats(&time_stats); > > > > time_stddev = stddev_stats(&time_stats); > > > > printf(" Average %ssynthesis took: %.3f usec (+- %.3f usec)\n", > > > > @@ -186,6 +187,7 @@ static int do_run_multi_threaded(struct target *target, > > > > perf_session__delete(session); > > > > } > > > > > > > > + fflush(stdout); > > > > time_average = avg_stats(&time_stats); > > > > time_stddev = stddev_stats(&time_stats); > > > > printf(" Average synthesis took: %.3f usec (+- %.3f usec)\n", > > > > -- > > > > 2.25.1 > > > > > > -- > > > > > > - Arnaldo > > > > -- > > > > - Arnaldo -- - Arnaldo