From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756816AbZHHC0p (ORCPT ); Fri, 7 Aug 2009 22:26:45 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754547AbZHHC0o (ORCPT ); Fri, 7 Aug 2009 22:26:44 -0400 Received: from fg-out-1718.google.com ([72.14.220.157]:34627 "EHLO fg-out-1718.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751841AbZHHC0n (ORCPT ); Fri, 7 Aug 2009 22:26:43 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references :mime-version:content-type:content-transfer-encoding; b=CVZa0wnispIhZIgHsCOVBzCebnsqje+PM16g5ZhEMfDDg+VBIpWPjpGinUrpczuHju i64PYsqvQnqANUHyxlhJ1yoGMDNtbp88kxHbz2vhqVjHqhBIkNxU9GHFHhABseuV4+6y KamM8xbOsknKsgD4YPS3cCZgzuJwPOXi5fjE4= From: Frederic Weisbecker To: Ingo Molnar Cc: LKML , Frederic Weisbecker , Peter Zijlstra , Arnaldo Carvalho de Melo , Mike Galbraith , Paul Mackerras Subject: [PATCH 1/3] perfcounter: Initialize tracepoint record before any use Date: Sat, 8 Aug 2009 04:26:35 +0200 Message-Id: <1249698400-5441-2-git-send-email-fweisbec@gmail.com> X-Mailer: git-send-email 1.6.2.3 In-Reply-To: <1249698400-5441-1-git-send-email-fweisbec@gmail.com> References: <1249698400-5441-1-git-send-email-fweisbec@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Despite that the tracepoint record is always present when the PERF_SAMPLE_TP_RECORD flag is set, gcc whines, thinking it might not be initialized: kernel/perf_counter.c: In function ‘perf_counter_output’: kernel/perf_counter.c:2650: warning: ‘tp’ may be used uninitialized in this function Then, initialize it to NULL and always check if it's not NULL before dereference it. Reported-by: Ingo Molnar Signed-off-by: Frederic Weisbecker Cc: Peter Zijlstra Cc: Arnaldo Carvalho de Melo Cc: Mike Galbraith Cc: Paul Mackerras --- kernel/perf_counter.c | 7 ++++--- 1 files changed, 4 insertions(+), 3 deletions(-) diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index 142ae5a..a6963e2 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -2647,7 +2647,7 @@ void perf_counter_output(struct perf_counter *counter, int nmi, u64 counter; } group_entry; struct perf_callchain_entry *callchain = NULL; - struct perf_tracepoint_record *tp; + struct perf_tracepoint_record *tp = NULL; int callchain_size = 0; u64 time; struct { @@ -2718,7 +2718,8 @@ void perf_counter_output(struct perf_counter *counter, int nmi, if (sample_type & PERF_SAMPLE_TP_RECORD) { tp = data->private; - header.size += tp->size; + if (tp) + header.size += tp->size; } ret = perf_output_begin(&handle, counter, header.size, nmi, 1); @@ -2784,7 +2785,7 @@ void perf_counter_output(struct perf_counter *counter, int nmi, } } - if (sample_type & PERF_SAMPLE_TP_RECORD) + if ((sample_type & PERF_SAMPLE_TP_RECORD) && tp) perf_output_copy(&handle, tp->record, tp->size); perf_output_end(&handle); -- 1.6.2.3