From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030561Ab2CNCa6 (ORCPT ); Tue, 13 Mar 2012 22:30:58 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.122]:23031 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030457Ab2CNC3r (ORCPT ); Tue, 13 Mar 2012 22:29:47 -0400 X-Authority-Analysis: v=2.0 cv=d9t3OGfE c=1 sm=0 a=ZycB6UtQUfgMyuk2+PxD7w==:17 a=XQbtiDEiEegA:10 a=UBy9sU4F98IA:10 a=7iRz-qJHzJMA:10 a=5SG0PmZfjMsA:10 a=bbbx4UPp9XUA:10 a=VwQbUJbxAAAA:8 a=meVymXHHAAAA:8 a=0oKUSnA67OczS7GyBKYA:9 a=Zh68SRI7RUMA:10 a=jeBq3FmKZ4MA:10 a=ZycB6UtQUfgMyuk2+PxD7w==:117 X-Cloudmark-Score: 0 X-Originating-IP: 74.67.80.29 Message-Id: <20120314022945.771027206@goodmis.org> User-Agent: quilt/0.50-1 Date: Tue, 13 Mar 2012 22:27:04 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org, linux-rt-users Cc: Thomas Gleixner , Carsten Emde , John Kacur , stable-rt@vger.kernel.org Subject: [PATCH RT 6/7] net: Use cpu_chill() instead of cpu_relax() References: <20120314022658.783312660@goodmis.org> Content-Disposition: inline; filename=0006-net-Use-cpu_chill-instead-of-cpu_relax.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Thomas Gleixner Retry loops on RT might loop forever when the modifying side was preempted. Use cpu_chill() instead of cpu_relax() to let the system make progress. Signed-off-by: Thomas Gleixner Cc: stable-rt@vger.kernel.org Signed-off-by: Steven Rostedt --- net/rds/ib_rdma.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) diff --git a/net/rds/ib_rdma.c b/net/rds/ib_rdma.c index 819c35a..256ad87 100644 --- a/net/rds/ib_rdma.c +++ b/net/rds/ib_rdma.c @@ -33,6 +33,7 @@ #include #include #include +#include #include "rds.h" #include "ib.h" @@ -294,7 +295,7 @@ static inline void wait_clean_list_grace(void) for_each_online_cpu(cpu) { flag = &per_cpu(clean_list_grace, cpu); while (test_bit(CLEAN_LIST_BUSY_BIT, flag)) - cpu_relax(); + cpu_chill(); } } -- 1.7.8.3