From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755286Ab0C3DAK (ORCPT ); Mon, 29 Mar 2010 23:00:10 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.125]:33271 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755164Ab0C3DAI (ORCPT ); Mon, 29 Mar 2010 23:00:08 -0400 X-Authority-Analysis: v=1.1 cv=8Rq9yliVGc3GxcN10kx+g7e/eWPAtZnInWtRlahw0rA= c=1 sm=0 a=Yn1NNCqElSgA:10 a=GzHTLUccyWwA:10 a=gMqfjgEr1zLu/65IO0LwxA==:17 a=YgwN3AOMAAAA:8 a=meVymXHHAAAA:8 a=aDKd03vN83iETk1HISEA:9 a=L-eaKcHn3eGKfouM-vUA:7 a=wTeIY82SsxzZEI_rrxVgGU2hVyUA:4 a=jeBq3FmKZ4MA:10 a=gMqfjgEr1zLu/65IO0LwxA==:117 X-Cloudmark-Score: 0 X-Originating-IP: 74.67.89.75 Message-Id: <20100330030006.132898398@goodmis.org> User-Agent: quilt/0.48-1 Date: Mon, 29 Mar 2010 22:58:02 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , Frederic Weisbecker , Julia Lawall Subject: [PATCH 2/2] ring-buffer: Add missing unlock References: <20100330025800.713540457@goodmis.org> Content-Disposition: inline; filename=0002-ring-buffer-Add-missing-unlock.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Julia Lawall In some error handling cases the lock is not unlocked. The return is converted to a goto, to share the unlock at the end of the function. A simplified version of the semantic patch that finds this problem is as follows: (http://coccinelle.lip6.fr/) // @r exists@ expression E1; identifier f; @@ f (...) { <+... * spin_lock_irq (E1,...); ... when != E1 * return ...; ...+> } // Signed-off-by: Julia Lawall LKML-Reference: Signed-off-by: Steven Rostedt --- kernel/trace/ring_buffer.c | 8 +++++--- 1 files changed, 5 insertions(+), 3 deletions(-) diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index d1187ef..9a0f9bf 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -1209,18 +1209,19 @@ rb_remove_pages(struct ring_buffer_per_cpu *cpu_buffer, unsigned nr_pages) for (i = 0; i < nr_pages; i++) { if (RB_WARN_ON(cpu_buffer, list_empty(cpu_buffer->pages))) - return; + goto out; p = cpu_buffer->pages->next; bpage = list_entry(p, struct buffer_page, list); list_del_init(&bpage->list); free_buffer_page(bpage); } if (RB_WARN_ON(cpu_buffer, list_empty(cpu_buffer->pages))) - return; + goto out; rb_reset_cpu(cpu_buffer); rb_check_pages(cpu_buffer); +out: spin_unlock_irq(&cpu_buffer->reader_lock); } @@ -1237,7 +1238,7 @@ rb_insert_pages(struct ring_buffer_per_cpu *cpu_buffer, for (i = 0; i < nr_pages; i++) { if (RB_WARN_ON(cpu_buffer, list_empty(pages))) - return; + goto out; p = pages->next; bpage = list_entry(p, struct buffer_page, list); list_del_init(&bpage->list); @@ -1246,6 +1247,7 @@ rb_insert_pages(struct ring_buffer_per_cpu *cpu_buffer, rb_reset_cpu(cpu_buffer); rb_check_pages(cpu_buffer); +out: spin_unlock_irq(&cpu_buffer->reader_lock); } -- 1.7.0