From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933171AbeCPRXQ (ORCPT ); Fri, 16 Mar 2018 13:23:16 -0400 Received: from userp2120.oracle.com ([156.151.31.85]:36990 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752927AbeCPRXN (ORCPT ); Fri, 16 Mar 2018 13:23:13 -0400 Subject: Re: [RESEND PATCH v2] sched/fair: Remove check in idle_balance against migration_cost To: Peter Zijlstra Cc: linux-kernel@vger.kernel.org, mingo@redhat.com, steven.sistare@oracle.com, joelaf@google.com, jbacik@fb.com, juri.lelli@redhat.com, dhaval.giani@oracle.com, efault@gmx.de, riel@surriel.com References: <1521052607-24622-1-git-send-email-rohit.k.jain@oracle.com> <20180316143550.GH4064@hirez.programming.kicks-ass.net> From: Rohit Jain Message-ID: <48b63847-123c-6a28-d558-392b8122cd7e@oracle.com> Date: Fri, 16 Mar 2018 10:21:54 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: <20180316143550.GH4064@hirez.programming.kicks-ass.net> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=8833 signatures=668690 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1711220000 definitions=main-1803160153 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Peter, On 03/16/2018 07:35 AM, Peter Zijlstra wrote: > On Wed, Mar 14, 2018 at 11:36:47AM -0700, Rohit Jain wrote: >> Signed-off-by: Rohit Jain >> >> Signed-off-by: Rohit Jain > Surely you only need a single on of those. Oh wow! I don't know how I missed this :) Thanks! >> --- >> kernel/sched/fair.c | 3 +-- >> 1 file changed, 1 insertion(+), 2 deletions(-) >> >> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c >> index 5eb3ffc..569ea83 100644 >> --- a/kernel/sched/fair.c >> +++ b/kernel/sched/fair.c >> @@ -8804,8 +8804,7 @@ static int idle_balance(struct rq *this_rq, struct rq_flags *rf) >> */ >> rq_unpin_lock(this_rq, rf); >> >> - if (this_rq->avg_idle < sysctl_sched_migration_cost || >> - !this_rq->rd->overload) { >> + if (!this_rq->rd->overload) { >> rcu_read_lock(); >> sd = rcu_dereference_check_sched_domain(this_rq->sd); >> if (sd) > I don't think that actually works right on the current tree. In > particular look at commit: > > 31e77c93e432 ("sched/fair: Update blocked load when newly idle") OK. I see from LKML the code has moved. However, when I clone from https://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git/ I cannot see the commit.