From nobody Sat Apr 11 03:54:33 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 647F5C25B08 for ; Wed, 17 Aug 2022 05:40:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238544AbiHQFkJ (ORCPT ); Wed, 17 Aug 2022 01:40:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58618 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238506AbiHQFj4 (ORCPT ); Wed, 17 Aug 2022 01:39:56 -0400 Received: from mail-yw1-x1149.google.com (mail-yw1-x1149.google.com [IPv6:2607:f8b0:4864:20::1149]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2EC4153D15 for ; Tue, 16 Aug 2022 22:39:49 -0700 (PDT) Received: by mail-yw1-x1149.google.com with SMTP id 00721157ae682-3328a211611so87240857b3.5 for ; Tue, 16 Aug 2022 22:39:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:references:mime-version:message-id:in-reply-to :date:from:to:cc; bh=iLN5+FLnhYIWqoDWLTWymRmT3HSuCKQDMghp6cr49+4=; b=RmO9zVA/7Wz8b9GtpWsugHokUFgVDsG4vXhQNbDdnCDmm9BYfj+EyK6z57xrOuwSr5 xEHy7nRGZdtn7j0pVRnsb79os9hz8xZ8L3I3H/+5RGvGbmAaY1KTeppz5YckCGTdlKFi WMmnxqPfR29q93koEqVqKV0oQyX6zZAGkY0X+m7nC1ZDpearMsBP/fqcS/s4uAbh7N4k VL5kJWQpBFQf16lVQU3Hz3d7rLu9p44+5RFbWVEZKnl4dC6PjnAHJBEy0jRaUu8zH2r1 brJNcJN3Lg6IsHi6eP1cNqo9Kcsv7W71EYHmTabd6r3Bc8KeGw+RTkqsFBciOOgkRjzC qIBw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:references:mime-version:message-id:in-reply-to :date:x-gm-message-state:from:to:cc; bh=iLN5+FLnhYIWqoDWLTWymRmT3HSuCKQDMghp6cr49+4=; b=49Eh2zHXQosNCiRBAQ26YOHa3MKRsV1nuOY4ebwKtF9PPL6JNp8uJj88zoGR2ysg0J 6YC6Ru/hIDkjagR6SmU8+oqDF+WM9hOn3v9gkYSX5BcgmdT5FV802n270ixcKhX8RXK0 h8Bt/Y1fVmTrAzA2fVkB7+uyrvIAHp9NsYXxrZPSTiwaDYgi980HxAhTukURf009d+ZY r/5N9LTZv7Ci960WzLJ6a6A4jTtF2sw5eTgSsV+uuYeDGVRHH5sbpNw/SFs2USTRt5Pj bFhAzxpcFMr5t/2bucTJ7LKICazCF0+g9yNzkvM7Xp0JCe/T7PShkVfxKX4mmwQQlo/9 Suew== X-Gm-Message-State: ACgBeo2pifAtlAOpzbOnbS9jr9HPnE01bUTFSs6yL65MAoB/oEs/P6zR 51CUCgj5D5dNL0aZgaa4rtJAoqtp0NtV X-Google-Smtp-Source: AA6agR5Ztfm8DnME40MFJ+L3pOkrk/LLHs6fSAOR1/U1JeP8TP+phIUcP0v3cVdGvdWh8ubaYa9KQriPDx3N X-Received: from irogers.svl.corp.google.com ([2620:15c:2d4:203:3bec:858f:9a6d:63de]) (user=irogers job=sendgmr) by 2002:a05:6902:920:b0:68f:a286:2a2b with SMTP id bu32-20020a056902092000b0068fa2862a2bmr3041696ybb.612.1660714788460; Tue, 16 Aug 2022 22:39:48 -0700 (PDT) Date: Tue, 16 Aug 2022 22:39:29 -0700 In-Reply-To: <20220817053930.769840-1-irogers@google.com> Message-Id: <20220817053930.769840-6-irogers@google.com> Mime-Version: 1.0 References: <20220817053930.769840-1-irogers@google.com> X-Mailer: git-send-email 2.37.1.595.g718a3a8f04-goog Subject: [PATCH v1 5/6] perf mutex: Fix thread safety analysis From: Ian Rogers To: Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Thomas Gleixner , Darren Hart , Davidlohr Bueso , "=?UTF-8?q?Andr=C3=A9=20Almeida?=" , Nathan Chancellor , Nick Desaulniers , Tom Rix , Athira Rajeev , Weiguo Li , Pavithra Gurushankar , Thomas Richter , Ravi Bangoria , Dario Petrillo , Wenyu Liu , Hewenliang , yaowenbin , Dave Marchevsky , Andrii Nakryiko , Alexandre Truong , Kim Phillips , Leo Yan , Quentin Monnet , William Cohen , Andres Freund , Song Liu , Adrian Hunter , "=?UTF-8?q?Martin=20Li=C5=A1ka?=" , Colin Ian King , James Clark , Fangrui Song , Stephane Eranian , Kajol Jain , Andi Kleen , Alexey Bayduraev , Riccardo Mancini , Masami Hiramatsu , Christophe JAILLET , Zechuan Chen , Jason Wang , Lexi Shao , Remi Bernon , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, llvm@lists.linux.dev Cc: Ian Rogers Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Add annotations to describe lock behavior. Add missing unlocks to perf_sched__replay. Alter hist_iter__top_callback as the thread-safety analysis cannot follow pointers through local variables. Signed-off-by: Ian Rogers --- tools/perf/builtin-sched.c | 8 ++++++++ tools/perf/builtin-top.c | 5 +++-- 2 files changed, 11 insertions(+), 2 deletions(-) diff --git a/tools/perf/builtin-sched.c b/tools/perf/builtin-sched.c index 0f52f73be896..a8a765ed28ce 100644 --- a/tools/perf/builtin-sched.c +++ b/tools/perf/builtin-sched.c @@ -658,6 +658,8 @@ static void *thread_func(void *ctx) } =20 static void create_tasks(struct perf_sched *sched) + EXCLUSIVE_LOCK_FUNCTION(sched->start_work_mutex) + EXCLUSIVE_LOCK_FUNCTION(sched->work_done_wait_mutex) { struct task_desc *task; pthread_attr_t attr; @@ -687,6 +689,8 @@ static void create_tasks(struct perf_sched *sched) } =20 static void wait_for_tasks(struct perf_sched *sched) + EXCLUSIVE_LOCKS_REQUIRED(sched->work_done_wait_mutex) + EXCLUSIVE_LOCKS_REQUIRED(sched->start_work_mutex) { u64 cpu_usage_0, cpu_usage_1; struct task_desc *task; @@ -738,6 +742,8 @@ static void wait_for_tasks(struct perf_sched *sched) } =20 static void run_one_test(struct perf_sched *sched) + EXCLUSIVE_LOCKS_REQUIRED(sched->work_done_wait_mutex) + EXCLUSIVE_LOCKS_REQUIRED(sched->start_work_mutex) { u64 T0, T1, delta, avg_delta, fluct; =20 @@ -3314,6 +3320,8 @@ static int perf_sched__replay(struct perf_sched *sche= d) for (i =3D 0; i < sched->replay_repeat; i++) run_one_test(sched); =20 + mutex_unlock(&sched->start_work_mutex); + mutex_unlock(&sched->work_done_wait_mutex); return 0; } =20 diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c index 3757292bfe86..e832f04e3076 100644 --- a/tools/perf/builtin-top.c +++ b/tools/perf/builtin-top.c @@ -196,6 +196,7 @@ static void perf_top__record_precise_ip(struct perf_top= *top, struct hist_entry *he, struct perf_sample *sample, struct evsel *evsel, u64 ip) + EXCLUSIVE_LOCKS_REQUIRED(he->hists->lock) { struct annotation *notes; struct symbol *sym =3D he->ms.sym; @@ -724,13 +725,13 @@ static void *display_thread(void *arg) static int hist_iter__top_callback(struct hist_entry_iter *iter, struct addr_location *al, bool single, void *arg) + EXCLUSIVE_LOCKS_REQUIRED(iter->he->hists->lock) { struct perf_top *top =3D arg; - struct hist_entry *he =3D iter->he; struct evsel *evsel =3D iter->evsel; =20 if (perf_hpp_list.sym && single) - perf_top__record_precise_ip(top, he, iter->sample, evsel, al->addr); + perf_top__record_precise_ip(top, iter->he, iter->sample, evsel, al->addr= ); =20 hist__account_cycles(iter->sample->branch_stack, al, iter->sample, !(top->record_opts.branch_stack & PERF_SAMPLE_BRANCH_ANY), --=20 2.37.1.595.g718a3a8f04-goog