From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A3A6113DBBD; Wed, 7 Oct 2026 00:07:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791331652; cv=none; b=O1YQQ2zMPJHirE1PSszGUqx+4QU3YoKGVB3UMl/8Jq8QniuU2TyYVr0Yk/Kdq5p/1nv4KWaXP82Ayy45UdC+MutPAtthAg9rEeGNkuqBPnT0wmwumFdWmSRMSgsuSl4TJE5x8Lq0Xks6pNJ1m6CMaXuSEKwoJbo1iyTb29UGXuU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791331652; c=relaxed/simple; bh=dtNhLMkF/zgvFqJCURZXVBTlAw67fzVf6wl54nOiIfU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=LLXD2z43PugQT8uw/PKO8OxOXQM9IYAI/jBlW3kj/AtKSvv0RMD/2p+TkvP4vdOdvjs3fNvi2qrswd99ngptKDM1KJYvA/YL6bh/5M26rVDRYAKhV3TwMOsPntMUvDJljmX02rQ5lC8i7M1/Y3M1VIehjE8aShIM/rwZNYS1Rro= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ZJg7N0Af; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ZJg7N0Af" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 044D51F0089B; Wed, 7 Oct 2026 00:07:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1791331651; bh=E9Jq0STvFwAswAqbthZnRem4rZFpZDkqPBhEZMJ2MaE=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=ZJg7N0Afja6whTUxuM9DD8jVYQLaZdDy7pHfqBpvWz/7w5jh1WJhUUv7Rm5egYI9r 7rG0lwHOdQ+5FGgy3Xx2wnl1S6DfAhGJ4QGCt9B6iiircc6LqKtd9+E7gdpRGEOAKX VikDMVe1STcuBxwxka7JheLj8fE9RSQ0TP6gqXGEOtRsiDcrANpPAvJNCUnDSR7hQU OrdhwA7vcTLX9XRHAbDixpsIRpG2S3hQxVzVjxx8oJXfD9Q1F7XhknF+mp1TkmSiKE 2pYsqZCBZLrbfgJnDIA/J6GeWjCAECHi8teptQLLTUhKSkSaxO6H+zC6PSMs2Yp9Sv f9IvdyLgnhygA== Date: Tue, 6 Oct 2026 17:07:29 -0700 From: Namhyung Kim To: Arnaldo Carvalho de Melo Cc: Ingo Molnar , Thomas Gleixner , James Clark , Jiri Olsa , Ian Rogers , Adrian Hunter , Clark Williams , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org Subject: Re: [PATCH v12 0/8] perf tools: Add progress diagnostics and a false-sharing workload Message-ID: References: <20261006145729.3028247-1-acme@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20261006145729.3028247-1-acme@kernel.org> On Tue, Oct 06, 2026 at 04:57:21PM +0200, Arnaldo Carvalho de Melo wrote: > Hi, > > This series adds progress diagnostics to perf, and a workload that makes > false sharing visible to data type profiling. > > The changes are: > > - move perf_config__set_variable() to util/config.c and serialize config > parser and read-modify-write state, so non-builtin perf code can persist > configuration changes safely; > > - add 'perf report --progress' for stdio users, showing the current phase, > percentage, and counts while a session is processed; > > - wire up 'perf report --no-progress', the counterpart of the option > above, for the TUI and GTK browsers, whose progress there is no other > way to turn off; > > - add 'perf test -w false_sharing', a synthetic TCP-shaped workload with > identity and packet counters sharing a cacheline, and include it in the > data type profiling shell test. > > Follow up work: the DO_ONCE() one-time init primitive added here mirrors > what the eight pre-existing raw pthread_once() users in util/ (annotate.c, > callchain.c, comm.c, dso.c, fncache.c, intel-tpebs.c, libbfd.c, pmus.c) > need, conversions that will also exercise the DEFINE_MUTEX() static > initializer; converting them is left for after this series. > Best regards, Reviewed-by: Namhyung Kim Thanks, Namhyung > > - Arnaldo > > What changed from v11: > > - The 'perf-stuck' patch is removed for the time being, to be submitted > separately later on; > > What changed from v10: > > - tools/perf/scripts/perf-stuck.sh: pin the watched process by its start > time, so a recycled PID can't get samples or gdb; Sashiko, v10; > > - tools/perf/scripts/perf-stuck.sh: drop the control characters from the > shown progress updates, no terminal escape injection; Sashiko, v10; > > - tools/perf/tests/shell/perf_stuck.sh: test the script, from option > validation to the gdb DIE chain runs on stand-in workloads; > > What changed from v9: > > - tools/perf/ui/stdio/progress.c: progress updates now work well with > the pager, printed to /dev/tty so they update in place; > > - tools/perf/scripts/perf-stuck.sh: take the last progress update > from a bounded tail window, dropping the \r's. Sashiko, v9; > > What changed from v8: > > - tools/perf/util/mutex.h: DEFINE_MUTEX() statics keep mutex_init()'s > !NDEBUG errorcheck type; > > - patch 4/9 commit log: clarify the acquire/release pairing, what the > dropped static key used to guarantee. > > What changed from v7: > > - tools/perf/util/mutex.h: the DO_ONCE() lockless fast path pairs its > __ATOMIC_ACQUIRE load with the __ATOMIC_RELEASE store. sashiko, v7; > > What changed from v6: > > - patch 1/5 split into four: the move, perf_etc_perfconfig() never > returning NULL, the DEFINE_MUTEX() prep and the serialization. > Namhyung Kim asked, v6; > > - tools/perf/util/{config.c,mutex.h}: perf's own mutex type, adding > the DEFINE_MUTEX() initializer it lacked. Namhyung Kim, v6; > > - tools/perf/util/mutex.h: add DO_ONCE() one-time init, from the > kernel's once.h, moving the lazy inits in config.c to it; > > - tools/perf/builtin-report.c: drop the option negation and stdio > hook comments Namhyung Kim asked to drop, reviewing v6; > > - tools/perf/scripts/perf-stuck.gdb: break the long printf() line. > Namhyung Kim, reviewing v6; > > - the false_sharing cset now carries the data type profiling output > with cacheline info. Namhyung Kim asked for it, reviewing v6. > > What changed from v5: > > - tools/perf/util/config.c: drop the config_file_name read in > bad_config(), locking would buy a consistent NULL. Sashiko, v5; > > - tools/perf/util/config.c: new config_set_mutex around the shared > set's init/teardown, home init via pthread_once. Sashiko, v5; > > - tools/perf/builtin-report.c, perf-report.txt: --no-progress is > --progress's auto negation, last wins. Namhyung Kim, reviewing v5. > > What changed from v4: > > - tools/perf/builtin-report.c: mark --progress PARSE_OPT_NOAUTONEG, > parse_long_opt() claimed --no-progress first. Sashiko, v4; > > - tools/perf/util/config.c: format the path buffer inside the critical > section. Sashiko pointed out the window, reviewing v4; > > - tools/perf/tests/workloads/false_sharing.c: walk every bit of the > affinity mask, not _SC_NPROCESSORS_CONF. Sashiko, reviewing v4. > > What changed from v3: > > - tools/perf/util/config.c: keep the buffer handed to the parser in > static storage. Sashiko, reviewing v3; > > - tools/perf/scripts/perf-stuck.gdb: perf-dso walks each dso candidate > until one evaluates, for REFCNT_CHECKING builds. Sashiko, v3; > > - tools/perf/tests/workloads/false_sharing.c: sum before cpu in struct > fs_reader, the padding after cpu rounded it to 128. Sashiko, v3; > > - tools/perf/builtin-report.c: --quiet wins over --progress, the phases > stay uncounted, documented next to it. Namhyung Kim, v3; > > - tools/perf/builtin-report.c, tools/perf/ui/progress.c: --no-progress > installs the no-op ops. Suggested by Namhyung Kim, reviewing v3; > > - tools/perf/scripts/perf-stuck.sh: check gdb is there before > watching. Namhyung Kim, reviewing v3. > > What changed from v2: > > - tools/perf/util/config.c: make perf_etc_perfconfig() total, falling > back to the unresolved path. Sashiko, reviewing v2; > > - tools/perf/scripts/perf-stuck.gdb: don't deref map_symbol.sym without > a NULL check. Sashiko, reviewing v2; > > - tools/perf/scripts/perf-stuck.gdb: note the REFCNT_CHECKING proxy > next to the structure walks; > > - tools/perf/scripts/perf-stuck.sh: count samples with no progress to > look at, an empty log never fired -g; > > - tools/perf/scripts/perf-stuck.sh: `--` for pgrep and tail against > names starting with a hyphen; > > - tools/perf/scripts/perf-stuck.sh: bound the gdb run with > `timeout --signal=INT 30`. > > What changed from v1: > > - avoid calling CPU_SET() with -1 when false_sharing runs with only one > CPU available in its affinity mask. > > tools/perf/Documentation/perf-report.txt | 19 ++ > tools/perf/builtin-config.c | 70 +---- > tools/perf/builtin-report.c | 9 + > tools/perf/tests/builtin-test.c | 1 + > tools/perf/tests/shell/data_type_profiling.sh | 9 +- > tools/perf/tests/tests.h | 1 + > tools/perf/tests/workloads/Build | 2 + > tools/perf/tests/workloads/false_sharing.c | 251 ++++++++++++++++++ > tools/perf/ui/Build | 1 + > tools/perf/ui/progress.c | 6 + > tools/perf/ui/progress.h | 4 + > tools/perf/ui/stdio/progress.c | 170 ++++++++++++ > tools/perf/util/config.c | 166 ++++++++++-- > tools/perf/util/config.h | 2 + > tools/perf/util/mutex.h | 36 +++ > tools/perf/util/ordered-events.c | 16 +- > tools/perf/util/session.c | 12 +- > 17 files changed, 675 insertions(+), 100 deletions(-) > create mode 100644 tools/perf/tests/workloads/false_sharing.c > create mode 100644 tools/perf/ui/stdio/progress.c > base-commit: 705da5b15ab89ba9 > v1-head: 45d7917f7e05e8a29828ed5f0bbdc94fc938f79f > v2-head: d4f84e4de8890194924ccd897a8e6773e7d4240b > v3-head: 485532296710225862daf8ffb19802ae327efe2a > v4-head: 38193635508e0a5f04a6ebf70db27534b68b2d5b > v5-head: e99bc48f6c72b9cc67b4e4143a0364acac5523bb > v6-head: 7dc99dbb6504f199c3c39487d91370d1bbb7a827 > v7-head: b357a76666d08f74eb99c755cca41855a96f6169 > v8-head: 257b5ea6115ad5126d2c881523ea6c660cf5d28c > v9-head: 70235104c6cf7d18d91f46de1a233abbeb65893a > v10-head: 1ecf850c2694d20ca9cd0014f2a42528ef4dbfec > v11-head: a3ddbaab18aa24fba520927f71d0ea66edfc5593 > --