Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758226AbZLGHM7 (ORCPT ); Mon, 7 Dec 2009 02:12:59 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757527AbZLGHM6 (ORCPT ); Mon, 7 Dec 2009 02:12:58 -0500 Received: from hera.kernel.org ([140.211.167.34]:51348 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756756AbZLGHM5 (ORCPT ); Mon, 7 Dec 2009 02:12:57 -0500 Date: Mon, 7 Dec 2009 07:12:33 GMT From: tip-bot for Ulrich Drepper Cc: linux-kernel@vger.kernel.org, drepper@redhat.com, hpa@zytor.com, mingo@redhat.com, tglx@linutronix.de, mingo@elte.hu Reply-To: mingo@redhat.com, hpa@zytor.com, drepper@redhat.com, linux-kernel@vger.kernel.org, tglx@linutronix.de, mingo@elte.hu In-Reply-To: <200912061825.nB6IPUa1023306@hs20-bc2-1.build.redhat.com> References: <200912061825.nB6IPUa1023306@hs20-bc2-1.build.redhat.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:perf/urgent] perf tools: Optimize parse_subsystem_tracepoint_event() Message-ID: Git-Commit-ID: 180570fdb7a3c404b599f0a318c2ccf86e4827ed X-Mailer: tip-git-log-daemon MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2453 Lines: 70 Commit-ID: 180570fdb7a3c404b599f0a318c2ccf86e4827ed Gitweb: http://git.kernel.org/tip/180570fdb7a3c404b599f0a318c2ccf86e4827ed Author: Ulrich Drepper AuthorDate: Sun, 6 Dec 2009 13:25:30 -0500 Committer: Ingo Molnar CommitDate: Mon, 7 Dec 2009 08:09:29 +0100 perf tools: Optimize parse_subsystem_tracepoint_event() Uses of strcat are almost always signs that someone is too lazy to think about the code a bit more carefully. One always has to know about the lengths of the strings involved to avoid buffer overflows. This is one case where the size of the object code for me is reduced by 38 bytes. The code should also be faster, especially if flags is non-NULL. Signed-off-by: Ulrich Drepper Cc: a.p.zijlstra@chello.nl Cc: fweisbec@gmail.com Cc: jaswinderrajput@gmail.com Cc: paulus@samba.org LKML-Reference: <200912061825.nB6IPUa1023306@hs20-bc2-1.build.redhat.com> Signed-off-by: Ingo Molnar --- tools/perf/util/parse-events.c | 15 +++------------ 1 files changed, 3 insertions(+), 12 deletions(-) diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c index 448a13b..e5bc0fb 100644 --- a/tools/perf/util/parse-events.c +++ b/tools/perf/util/parse-events.c @@ -467,7 +467,6 @@ parse_subsystem_tracepoint_event(char *sys_name, char *flags) while ((evt_ent = readdir(evt_dir))) { char event_opt[MAX_EVOPT_LEN + 1]; int len; - unsigned int rem = MAX_EVOPT_LEN; if (!strcmp(evt_ent->d_name, ".") || !strcmp(evt_ent->d_name, "..") @@ -475,20 +474,12 @@ parse_subsystem_tracepoint_event(char *sys_name, char *flags) || !strcmp(evt_ent->d_name, "filter")) continue; - len = snprintf(event_opt, MAX_EVOPT_LEN, "%s:%s", sys_name, - evt_ent->d_name); + len = snprintf(event_opt, MAX_EVOPT_LEN, "%s:%s%s%s", sys_name, + evt_ent->d_name, flags ? ":" : "", + flags ?: ""); if (len < 0) return EVT_FAILED; - rem -= len; - if (flags) { - if (rem < strlen(flags) + 1) - return EVT_FAILED; - - strcat(event_opt, ":"); - strcat(event_opt, flags); - } - if (parse_events(NULL, event_opt, 0)) return EVT_FAILED; } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/