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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 A1C26C43331 for ; Thu, 7 Nov 2019 19:01:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7A04521D7B for ; Thu, 7 Nov 2019 19:01:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573153305; bh=t/QgRpHFU2LPSl3N9NmsAbB0ibf1Lo3gcHs2HA98WTA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ekT5mASMkXB7DbQJA2k8wIpcj4DiFS/JdarGVzVmXXn8TFDvIdWAG8hwFgnuABA6k OTsCdAsiu5ImD3CTq/L9gkt4sMOJwR3ptB98WcBxULnq8TM9mIifHJ9LsAqrBJkmQD mSr1tn/3/iHYm5kdHezCJYEJROx5WimFC2nDkIew= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728263AbfKGTBo (ORCPT ); Thu, 7 Nov 2019 14:01:44 -0500 Received: from mail.kernel.org ([198.145.29.99]:41058 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725851AbfKGTBm (ORCPT ); Thu, 7 Nov 2019 14:01:42 -0500 Received: from quaco.ghostprotocols.net (179-240-172-58.3g.claro.net.br [179.240.172.58]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A4C522085B; Thu, 7 Nov 2019 19:01:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573153301; bh=t/QgRpHFU2LPSl3N9NmsAbB0ibf1Lo3gcHs2HA98WTA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OnYfglODqyxPTYSEDhjmAe4WoATJIyD2mYLocg7NlBQwiO7dboT8D+hsOSQJaqjkV BnDfc9nFu/CjAy3c54psmbyIFEPX8u+DO97vukl1lGImVyBgTOD2SYayE3roB4E8n2 WLMh1HiI+mekGppwETAbWsjYBMY9eYvoTGw9RPkk= From: Arnaldo Carvalho de Melo To: Ingo Molnar , Thomas Gleixner Cc: Jiri Olsa , Namhyung Kim , Clark Williams , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Andi Kleen , Kan Liang , Peter Zijlstra , Stephane Eranian , Arnaldo Carvalho de Melo Subject: [PATCH 09/63] perf evsel: Always preserve errno while cleaning up perf_event_open failures Date: Thu, 7 Nov 2019 15:59:17 -0300 Message-Id: <20191107190011.23924-10-acme@kernel.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20191107190011.23924-1-acme@kernel.org> References: <20191107190011.23924-1-acme@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Andi Kleen In some cases when perf_event_open fails, it may do some closes to clean up. In special cases these closes can fail too, which overwrites the errno of the perf_event_open, which is then incorrectly reported. Save/restore errno around closes. Signed-off-by: Andi Kleen Acked-by: Jiri Olsa Cc: Kan Liang Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lore.kernel.org/lkml/20191020175202.32456-2-andi@firstfloor.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/evsel.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c index abc7fda4a0fe..d831038b55f2 100644 --- a/tools/perf/util/evsel.c +++ b/tools/perf/util/evsel.c @@ -1574,7 +1574,7 @@ int evsel__open(struct evsel *evsel, struct perf_cpu_map *cpus, { int cpu, thread, nthreads; unsigned long flags = PERF_FLAG_FD_CLOEXEC; - int pid = -1, err; + int pid = -1, err, old_errno; enum { NO_CHANGE, SET_TO_MAX, INCREASED_MAX } set_rlimit = NO_CHANGE; if ((perf_missing_features.write_backward && evsel->core.attr.write_backward) || @@ -1727,8 +1727,8 @@ int evsel__open(struct evsel *evsel, struct perf_cpu_map *cpus, */ if (err == -EMFILE && set_rlimit < INCREASED_MAX) { struct rlimit l; - int old_errno = errno; + old_errno = errno; if (getrlimit(RLIMIT_NOFILE, &l) == 0) { if (set_rlimit == NO_CHANGE) l.rlim_cur = l.rlim_max; @@ -1812,6 +1812,7 @@ int evsel__open(struct evsel *evsel, struct perf_cpu_map *cpus, if (err) threads->err_thread = thread; + old_errno = errno; do { while (--thread >= 0) { close(FD(evsel, cpu, thread)); @@ -1819,6 +1820,7 @@ int evsel__open(struct evsel *evsel, struct perf_cpu_map *cpus, } thread = nthreads; } while (--cpu >= 0); + errno = old_errno; return err; } -- 2.21.0