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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id AC385C6FD1A for ; Tue, 7 Mar 2023 17:23:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231420AbjCGRXL (ORCPT ); Tue, 7 Mar 2023 12:23:11 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41578 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230190AbjCGRWl (ORCPT ); Tue, 7 Mar 2023 12:22:41 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 122044ECE8 for ; Tue, 7 Mar 2023 09:18:08 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 7AE496150C for ; Tue, 7 Mar 2023 17:18:08 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4DF65C433A1; Tue, 7 Mar 2023 17:18:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1678209487; bh=Yqrs8HTGisDdywa3JPQeocUGX9CBGTZCMFQettr/AWc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=GYKbZfoqwpPRGduIBji+pYYHMeXe6xBAacI75dP3Epr1dI7JKqLYjetYGN+4yCiKP SiPnHOY3CJGm2Q+WFt+sMjQxnqfZaJtgrSl0k4f3wpALxyArtkEbX6468PYgzDJTte Q6V3GsjZiG3KlEnbNNczYiMJTEzCdFeRGyCyKYXg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Tonghao Zhang , Quentin Monnet , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Martin KaFai Lau , Sasha Levin Subject: [PATCH 6.2 0236/1001] bpftool: profile online CPUs instead of possible Date: Tue, 7 Mar 2023 17:50:08 +0100 Message-Id: <20230307170032.080686152@linuxfoundation.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230307170022.094103862@linuxfoundation.org> References: <20230307170022.094103862@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Tonghao Zhang [ Upstream commit 377c16fa3f3c60d21e4b05314c8be034ce37f2eb ] The number of online cpu may be not equal to possible cpu. "bpftool prog profile" can not create pmu event on possible but on online cpu. $ dmidecode -s system-product-name PowerEdge R620 $ cat /sys/devices/system/cpu/possible 0-47 $ cat /sys/devices/system/cpu/online 0-31 Disable cpu dynamically: $ echo 0 > /sys/devices/system/cpu/cpuX/online If one cpu is offline, perf_event_open will return ENODEV. To fix this issue: * check value returned and skip offline cpu. * close pmu_fd immediately on error path, avoid fd leaking. Fixes: 47c09d6a9f67 ("bpftool: Introduce "prog profile" command") Signed-off-by: Tonghao Zhang Cc: Quentin Monnet Cc: Alexei Starovoitov Cc: Daniel Borkmann Cc: Andrii Nakryiko Cc: Martin KaFai Lau Cc: Song Liu Cc: Yonghong Song Cc: John Fastabend Cc: KP Singh Cc: Stanislav Fomichev Cc: Hao Luo Cc: Jiri Olsa Acked-by: John Fastabend Link: https://lore.kernel.org/r/20230202131701.29519-1-tong@infragraf.org Signed-off-by: Martin KaFai Lau Signed-off-by: Sasha Levin --- tools/bpf/bpftool/prog.c | 38 ++++++++++++++++++++++++++++++-------- 1 file changed, 30 insertions(+), 8 deletions(-) diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index cfc9fdc1e8634..e87738dbffc10 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -2233,10 +2233,38 @@ static void profile_close_perf_events(struct profiler_bpf *obj) profile_perf_event_cnt = 0; } +static int profile_open_perf_event(int mid, int cpu, int map_fd) +{ + int pmu_fd; + + pmu_fd = syscall(__NR_perf_event_open, &metrics[mid].attr, + -1 /*pid*/, cpu, -1 /*group_fd*/, 0); + if (pmu_fd < 0) { + if (errno == ENODEV) { + p_info("cpu %d may be offline, skip %s profiling.", + cpu, metrics[mid].name); + profile_perf_event_cnt++; + return 0; + } + return -1; + } + + if (bpf_map_update_elem(map_fd, + &profile_perf_event_cnt, + &pmu_fd, BPF_ANY) || + ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0)) { + close(pmu_fd); + return -1; + } + + profile_perf_events[profile_perf_event_cnt++] = pmu_fd; + return 0; +} + static int profile_open_perf_events(struct profiler_bpf *obj) { unsigned int cpu, m; - int map_fd, pmu_fd; + int map_fd; profile_perf_events = calloc( sizeof(int), obj->rodata->num_cpu * obj->rodata->num_metric); @@ -2255,17 +2283,11 @@ static int profile_open_perf_events(struct profiler_bpf *obj) if (!metrics[m].selected) continue; for (cpu = 0; cpu < obj->rodata->num_cpu; cpu++) { - pmu_fd = syscall(__NR_perf_event_open, &metrics[m].attr, - -1/*pid*/, cpu, -1/*group_fd*/, 0); - if (pmu_fd < 0 || - bpf_map_update_elem(map_fd, &profile_perf_event_cnt, - &pmu_fd, BPF_ANY) || - ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0)) { + if (profile_open_perf_event(m, cpu, map_fd)) { p_err("failed to create event %s on cpu %d", metrics[m].name, cpu); return -1; } - profile_perf_events[profile_perf_event_cnt++] = pmu_fd; } } return 0; -- 2.39.2