From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E38D1C432BE for ; Mon, 30 Aug 2021 03:22:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CBA2160E98 for ; Mon, 30 Aug 2021 03:22:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229915AbhH3DX3 (ORCPT ); Sun, 29 Aug 2021 23:23:29 -0400 Received: from out4436.biz.mail.alibaba.com ([47.88.44.36]:42784 "EHLO out4436.biz.mail.alibaba.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229713AbhH3DXX (ORCPT ); Sun, 29 Aug 2021 23:23:23 -0400 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R151e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e01424;MF=changhuaixin@linux.alibaba.com;NM=1;PH=DS;RN=24;SR=0;TI=SMTPD_---0UmVOmcq_1630293743; Received: from localhost(mailfrom:changhuaixin@linux.alibaba.com fp:SMTPD_---0UmVOmcq_1630293743) by smtp.aliyun-inc.com(127.0.0.1); Mon, 30 Aug 2021 11:22:23 +0800 From: Huaixin Chang To: linux-kernel@vger.kernel.org Cc: peterz@infradead.org, anderson@cs.unc.edu, baruah@wustl.edu, bsegall@google.com, changhuaixin@linux.alibaba.com, dietmar.eggemann@arm.com, dtcccc@linux.alibaba.com, juri.lelli@redhat.com, khlebnikov@yandex-team.ru, luca.abeni@santannapisa.it, mgorman@suse.de, mingo@redhat.com, odin@uged.al, odin@ugedal.com, pauld@redhead.com, pjt@google.com, rostedt@goodmis.org, shanpeic@linux.alibaba.com, tj@kernel.org, tommaso.cucinotta@santannapisa.it, vincent.guittot@linaro.org, xiyou.wangcong@gmail.com, daniel.m.jordan@oracle.com Subject: [PATCH 1/2] sched/fair: Add cfs bandwidth burst statistics Date: Mon, 30 Aug 2021 11:22:14 +0800 Message-Id: <20210830032215.16302-2-changhuaixin@linux.alibaba.com> X-Mailer: git-send-email 2.14.4.44.g2045bb6 In-Reply-To: <20210830032215.16302-1-changhuaixin@linux.alibaba.com> References: <20210830032215.16302-1-changhuaixin@linux.alibaba.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Two new statistics are introduced to show the internal of burst feature and explain why burst helps or not. nr_bursts: number of periods bandwidth burst occurs burst_time: cumulative wall-time (in nanoseconds) that any cpus has used above quota in respective periods Co-developed-by: Shanpei Chen Signed-off-by: Shanpei Chen Co-developed-by: Tianchen Ding Signed-off-by: Tianchen Ding Signed-off-by: Huaixin Chang --- kernel/sched/core.c | 13 ++++++++++--- kernel/sched/fair.c | 9 +++++++++ kernel/sched/sched.h | 3 +++ 3 files changed, 22 insertions(+), 3 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 20ffcc044134..d00b92712253 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -10068,6 +10068,9 @@ static int cpu_cfs_stat_show(struct seq_file *sf, void *v) seq_printf(sf, "wait_sum %llu\n", ws); } + seq_printf(sf, "nr_bursts %d\n", cfs_b->nr_burst); + seq_printf(sf, "burst_time %llu\n", cfs_b->burst_time); + return 0; } #endif /* CONFIG_CFS_BANDWIDTH */ @@ -10164,16 +10167,20 @@ static int cpu_extra_stat_show(struct seq_file *sf, { struct task_group *tg = css_tg(css); struct cfs_bandwidth *cfs_b = &tg->cfs_bandwidth; - u64 throttled_usec; + u64 throttled_usec, burst_usec; throttled_usec = cfs_b->throttled_time; do_div(throttled_usec, NSEC_PER_USEC); + burst_usec = cfs_b->burst_time; + do_div(burst_usec, NSEC_PER_USEC); seq_printf(sf, "nr_periods %d\n" "nr_throttled %d\n" - "throttled_usec %llu\n", + "throttled_usec %llu\n" + "nr_bursts %d\n" + "burst_usec %llu\n", cfs_b->nr_periods, cfs_b->nr_throttled, - throttled_usec); + throttled_usec, cfs_b->nr_burst, burst_usec); } #endif return 0; diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 44c452072a1b..464371f364f1 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -4655,11 +4655,20 @@ static inline u64 sched_cfs_bandwidth_slice(void) */ void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b) { + s64 runtime; + if (unlikely(cfs_b->quota == RUNTIME_INF)) return; cfs_b->runtime += cfs_b->quota; + runtime = cfs_b->runtime_snap - cfs_b->runtime; + if (runtime > 0) { + cfs_b->burst_time += runtime; + cfs_b->nr_burst++; + } + cfs_b->runtime = min(cfs_b->runtime, cfs_b->quota + cfs_b->burst); + cfs_b->runtime_snap = cfs_b->runtime; } static inline struct cfs_bandwidth *tg_cfs_bandwidth(struct task_group *tg) diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 14a41a243f7b..80e4322727b4 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -367,6 +367,7 @@ struct cfs_bandwidth { u64 quota; u64 runtime; u64 burst; + u64 runtime_snap; s64 hierarchical_quota; u8 idle; @@ -379,7 +380,9 @@ struct cfs_bandwidth { /* Statistics: */ int nr_periods; int nr_throttled; + int nr_burst; u64 throttled_time; + u64 burst_time; #endif }; -- 2.14.4.44.g2045bb6