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 X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AEC2BC07E95 for ; Tue, 13 Jul 2021 11:22:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8ABA76127C for ; Tue, 13 Jul 2021 11:22:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235557AbhGMLZr (ORCPT ); Tue, 13 Jul 2021 07:25:47 -0400 Received: from szxga01-in.huawei.com ([45.249.212.187]:6809 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235413AbhGMLZr (ORCPT ); Tue, 13 Jul 2021 07:25:47 -0400 Received: from dggemv711-chm.china.huawei.com (unknown [172.30.72.56]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4GPJ4n2Z0czXs9R; Tue, 13 Jul 2021 19:17:13 +0800 (CST) Received: from dggpemm000003.china.huawei.com (7.185.36.128) by dggemv711-chm.china.huawei.com (10.1.198.66) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2176.2; Tue, 13 Jul 2021 19:22:50 +0800 Received: from ubuntu1804.huawei.com (10.67.174.61) by dggpemm000003.china.huawei.com (7.185.36.128) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2176.2; Tue, 13 Jul 2021 19:22:49 +0800 From: Yang Jihong To: , , , , , , , , , , CC: Subject: [PATCH] perf sched: Fix record failed when CONFIG_SCHEDSTATS is not set Date: Tue, 13 Jul 2021 19:23:58 +0800 Message-ID: <20210713112358.194693-1-yangjihong1@huawei.com> X-Mailer: git-send-email 2.30.GIT MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII X-Originating-IP: [10.67.174.61] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To dggpemm000003.china.huawei.com (7.185.36.128) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-perf-users@vger.kernel.org The tracepoints trace_sched_stat_{wait, sleep, iowait} are not exposed to user if CONFIG_SCHEDSTATS is not set, "perf sched record" records the three events. As a result, the command fails to be executed. Before: #perf sched record sleep 1 event syntax error: 'sched:sched_stat_wait' \___ unknown tracepoint Error: File /sys/kernel/tracing/events/sched/sched_stat_wait not found. Hint: Perhaps this kernel misses some CONFIG_ setting to enable this feature?. Run 'perf list' for a list of valid events Usage: perf record [] [] or: perf record [] -- [] -e, --event event selector. use 'perf list' to list available events Solution: Check whether schedstat tracepoints are exposed. If no, these events are not recorded. After: # perf sched record sleep 1 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.163 MB perf.data (1091 samples) ] # perf sched report run measurement overhead: 4736 nsecs sleep measurement overhead: 9059979 nsecs the run test took 999854 nsecs the sleep test took 8945271 nsecs nr_run_events: 716 nr_sleep_events: 785 nr_wakeup_events: 0 ... ------------------------------------------------------------ Fixes: 2a09b5de235a6 ("sched/fair: do not expose some tracepoints to user if CONFIG_SCHEDSTATS is not set") Signed-off-by: Yang Jihong --- tools/perf/builtin-sched.c | 33 +++++++++++++++++++++++++++++---- 1 file changed, 29 insertions(+), 4 deletions(-) diff --git a/tools/perf/builtin-sched.c b/tools/perf/builtin-sched.c index 954ce2f594e9..3e5b7faf0c16 100644 --- a/tools/perf/builtin-sched.c +++ b/tools/perf/builtin-sched.c @@ -3335,6 +3335,16 @@ static void setup_sorting(struct perf_sched *sched, const struct option *options sort_dimension__add("pid", &sched->cmp_pid); } +static bool schedstat_events_exposed(void) +{ + /* + * Select "sched:sched_stat_wait" event to check + * whether schedstat tracepoints are exposed. + */ + return IS_ERR(trace_event__tp_format("sched", "sched_stat_wait")) ? + false : true; +} + static int __cmd_record(int argc, const char **argv) { unsigned int rec_argc, i, j; @@ -3346,21 +3356,33 @@ static int __cmd_record(int argc, const char **argv) "-m", "1024", "-c", "1", "-e", "sched:sched_switch", - "-e", "sched:sched_stat_wait", - "-e", "sched:sched_stat_sleep", - "-e", "sched:sched_stat_iowait", "-e", "sched:sched_stat_runtime", "-e", "sched:sched_process_fork", "-e", "sched:sched_wakeup_new", "-e", "sched:sched_migrate_task", }; + + /* + * The tracepoints trace_sched_stat_{wait, sleep, iowait} + * are not exposed to user if CONFIG_SCHEDSTATS is not set, + * to prevent "perf sched record" execution failure, determine + * whether to record schedstat events according to actual situation. + */ + const char * const schedstat_args[] = { + "-e", "sched:sched_stat_wait", + "-e", "sched:sched_stat_sleep", + "-e", "sched:sched_stat_iowait", + }; + unsigned int schedstat_argc = schedstat_events_exposed() ? + ARRAY_SIZE(schedstat_args) : 0; + struct tep_event *waking_event; /* * +2 for either "-e", "sched:sched_wakeup" or * "-e", "sched:sched_waking" */ - rec_argc = ARRAY_SIZE(record_args) + 2 + argc - 1; + rec_argc = ARRAY_SIZE(record_args) + 2 + schedstat_argc + argc - 1; rec_argv = calloc(rec_argc + 1, sizeof(char *)); if (rec_argv == NULL) @@ -3376,6 +3398,9 @@ static int __cmd_record(int argc, const char **argv) else rec_argv[i++] = strdup("sched:sched_wakeup"); + for (j = 0; j < schedstat_argc; j++) + rec_argv[i++] = strdup(schedstat_args[j]); + for (j = 1; j < (unsigned int)argc; j++, i++) rec_argv[i] = argv[j]; -- 2.30.GIT