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=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 44338C4BA09 for ; Wed, 26 Feb 2020 02:52:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2104621744 for ; Wed, 26 Feb 2020 02:52:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730287AbgBZCw1 (ORCPT ); Tue, 25 Feb 2020 21:52:27 -0500 Received: from mail5.windriver.com ([192.103.53.11]:45572 "EHLO mail5.wrs.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729890AbgBZCw1 (ORCPT ); Tue, 25 Feb 2020 21:52:27 -0500 Received: from ALA-HCA.corp.ad.wrs.com (ala-hca.corp.ad.wrs.com [147.11.189.40]) by mail5.wrs.com (8.15.2/8.15.2) with ESMTPS id 01Q2nYvk014201 (version=TLSv1 cipher=AES256-SHA bits=256 verify=FAIL); Tue, 25 Feb 2020 18:49:45 -0800 Received: from [128.224.162.175] (128.224.162.175) by ALA-HCA.corp.ad.wrs.com (147.11.189.50) with Microsoft SMTP Server (TLS) id 14.3.468.0; Tue, 25 Feb 2020 18:49:24 -0800 Subject: Re: [PATCH 2/2] perf: probe-file: Check return value of strlist__add To: Masami Hiramatsu CC: , , , , , , , , , References: <1582641703-233485-1-git-send-email-zhe.he@windriver.com> <1582641703-233485-2-git-send-email-zhe.he@windriver.com> <20200226074906.0acb08b31d01c96c475da0cb@kernel.org> From: He Zhe Message-ID: Date: Wed, 26 Feb 2020 10:49:19 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.4.1 MIME-Version: 1.0 In-Reply-To: <20200226074906.0acb08b31d01c96c475da0cb@kernel.org> Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Content-Language: en-US X-Originating-IP: [128.224.162.175] Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2/26/20 6:49 AM, Masami Hiramatsu wrote: > On Tue, 25 Feb 2020 22:41:43 +0800 > wrote: > >> From: He Zhe >> >> strlist__add may fail with -ENOMEM or -EEXIST. Check it and give debugging >> hint when necessary. >> >> Signed-off-by: He Zhe >> --- >> tools/perf/builtin-probe.c | 30 ++++++++++++++++-------------- >> tools/perf/util/probe-file.c | 26 +++++++++++++++++++++----- >> 2 files changed, 37 insertions(+), 19 deletions(-) >> >> diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c >> index 26bc5923e6b5..8b4511c70fed 100644 >> --- a/tools/perf/builtin-probe.c >> +++ b/tools/perf/builtin-probe.c >> @@ -442,24 +442,26 @@ static int perf_del_probe_events(struct strfilter *filter) >> } >> >> ret = probe_file__get_events(kfd, filter, klist); >> - if (ret == 0) { >> - strlist__for_each_entry(ent, klist) >> - pr_info("Removed event: %s\n", ent->s); >> + if (ret < 0) >> + goto out; > No, this is ignored by design. > Since probe_file__get_events() returns -ENOENT when no event is matched, > this should be just ignored, and goto uprobe event matching. Thanks for pointing it out. However when strlist__add in probe_file__get_events returns a -ENOMEM and we ignore that, though it happens not very likely, we would miss some entries. So I add checks here and in probe_file__get_events to give a heads-up in advance. And the same reason is for the checks below for probe_cache__load, probe_cache__add_entry and probe_cache__scan_sdt. Regards, Zhe > >> >> - ret = probe_file__del_strlist(kfd, klist); >> - if (ret < 0) >> - goto error; >> - } >> + strlist__for_each_entry(ent, klist) >> + pr_info("Removed event: %s\n", ent->s); >> + >> + ret = probe_file__del_strlist(kfd, klist); >> + if (ret < 0) >> + goto error; >> >> ret2 = probe_file__get_events(ufd, filter, ulist); >> - if (ret2 == 0) { >> - strlist__for_each_entry(ent, ulist) >> - pr_info("Removed event: %s\n", ent->s); >> + if (ret2 < 0) >> + goto out; > Ditto. > > Thank you, > >> >> - ret2 = probe_file__del_strlist(ufd, ulist); >> - if (ret2 < 0) >> - goto error; >> - } >> + strlist__for_each_entry(ent, ulist) >> + pr_info("Removed event: %s\n", ent->s); >> + >> + ret2 = probe_file__del_strlist(ufd, ulist); >> + if (ret2 < 0) >> + goto error; >> >> if (ret == -ENOENT && ret2 == -ENOENT) >> pr_warning("\"%s\" does not hit any event.\n", str); >> diff --git a/tools/perf/util/probe-file.c b/tools/perf/util/probe-file.c >> index cf44c05f89c1..00f086cba88f 100644 >> --- a/tools/perf/util/probe-file.c >> +++ b/tools/perf/util/probe-file.c >> @@ -307,10 +307,14 @@ int probe_file__get_events(int fd, struct strfilter *filter, >> p = strchr(ent->s, ':'); >> if ((p && strfilter__compare(filter, p + 1)) || >> strfilter__compare(filter, ent->s)) { >> - strlist__add(plist, ent->s); >> - ret = 0; >> + ret = strlist__add(plist, ent->s); >> + if (ret < 0) { >> + pr_debug("strlist__add failed (%d)\n", ret); >> + goto out; >> + } >> } >> } >> +out: >> strlist__delete(namelist); >> >> return ret; >> @@ -517,7 +521,11 @@ static int probe_cache__load(struct probe_cache *pcache) >> ret = -EINVAL; >> goto out; >> } >> - strlist__add(entry->tevlist, buf); >> + ret = strlist__add(entry->tevlist, buf); >> + if (ret < 0) { >> + pr_debug("strlist__add failed (%d)\n", ret); >> + goto out; >> + } >> } >> } >> out: >> @@ -678,7 +686,12 @@ int probe_cache__add_entry(struct probe_cache *pcache, >> command = synthesize_probe_trace_command(&tevs[i]); >> if (!command) >> goto out_err; >> - strlist__add(entry->tevlist, command); >> + ret = strlist__add(entry->tevlist, command); >> + if (ret < 0) { >> + pr_debug("strlist__add failed (%d)\n", ret); >> + goto out_err; >> + } >> + >> free(command); >> } >> list_add_tail(&entry->node, &pcache->entries); >> @@ -859,7 +872,10 @@ int probe_cache__scan_sdt(struct probe_cache *pcache, const char *pathname) >> break; >> } >> >> - strlist__add(entry->tevlist, buf); >> + ret = strlist__add(entry->tevlist, buf); >> + if (ret < 0) >> + pr_debug("strlist__add failed (%d)\n", ret); >> + >> free(buf); >> entry = NULL; >> } >> -- >> 2.24.1 >> >