From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751967AbdHGDvt (ORCPT ); Sun, 6 Aug 2017 23:51:49 -0400 Received: from LGEAMRELO12.lge.com ([156.147.23.52]:33683 "EHLO lgeamrelo12.lge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751411AbdHGDvs (ORCPT ); Sun, 6 Aug 2017 23:51:48 -0400 X-Original-SENDERIP: 156.147.1.125 X-Original-MAILFROM: byungchul.park@lge.com X-Original-SENDERIP: 10.177.222.33 X-Original-MAILFROM: byungchul.park@lge.com From: Byungchul Park To: peterz@infradead.org, mingo@kernel.org Cc: linux-kernel@vger.kernel.org, juri.lelli@gmail.com, rostedt@goodmis.org, kernel-team@lge.com Subject: [PATCH v6 0/2] Make find_later_rq() choose a closer cpu in topology Date: Mon, 7 Aug 2017 12:50:32 +0900 Message-Id: <1502077834-11137-1-git-send-email-byungchul.park@lge.com> X-Mailer: git-send-email 1.9.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When cpudl_find() returns any among free_cpus, the cpu might not be closer than others, considering sched domain. For example: this_cpu: 15 free_cpus: 0, 1,..., 14 (== later_mask) best_cpu: 0 topology: 0 --+ +--+ 1 --+ | +-- ... --+ 2 --+ | | +--+ | 3 --+ | ... ... 12 --+ | +--+ | 13 --+ | | +-- ... -+ 14 --+ | +--+ 15 --+ In this case, it would be best to select 14 since it's a free cpu and closest to 15(this_cpu). However, currently the code select 0(best_cpu) even though that's just any among free_cpus. Fix it. Change from v5 -. exclude two patches already picked up by peterz (sched/deadline: Make find_later_rq() choose a closer cpu in topology) (sched/deadline: Change return value of cpudl_find()) -. apply what peterz fixed for 'prefer sibling', into deadline and rt Change from v4 -. remove a patch that might cause huge lock contention (by spin lock(&cpudl.lock) in a hot path of scheduler) Change from v3 -. rename closest_cpu to best_cpu so that it align with rt -. protect referring cpudl.elements with cpudl.lock -. change return value of cpudl_find() to bool Change from v2 -. add support for SD_PREFER_SIBLING Change from v1 -. clean up the patch Byungchul Park (2): sched/deadline: Add support for SD_PREFER_SIBLING on find_later_rq() sched/rt: Add support for SD_PREFER_SIBLING on find_lowest_rq() kernel/sched/deadline.c | 46 +++++++++++++++++++++++++++++++++++++++++++--- kernel/sched/rt.c | 47 ++++++++++++++++++++++++++++++++++++++++++++--- 2 files changed, 87 insertions(+), 6 deletions(-) -- 1.9.1