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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CF3EDC433EF for ; Fri, 15 Oct 2021 12:50:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B5E30610E5 for ; Fri, 15 Oct 2021 12:50:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239164AbhJOMwu (ORCPT ); Fri, 15 Oct 2021 08:52:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60434 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239115AbhJOMwn (ORCPT ); Fri, 15 Oct 2021 08:52:43 -0400 Received: from mail-wr1-x429.google.com (mail-wr1-x429.google.com [IPv6:2a00:1450:4864:20::429]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EFAADC061570 for ; Fri, 15 Oct 2021 05:50:36 -0700 (PDT) Received: by mail-wr1-x429.google.com with SMTP id o20so26396286wro.3 for ; Fri, 15 Oct 2021 05:50:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=UPOdXwC1kuNdyAL0bf/AY2eNEz9jvw3Kld7w4EKJpxM=; b=CVS0a1oceUmEd+Kx09zCyhBzMhQzLhie+p8zNt/jDyo/wVLe/igIW4TfWAw7629FDf +MFPKKfOR0HKyh9QsJ+TmRCnTbGPEipU7oh+ZdfybdDXTnPP7iJhxaaiYQBbMpDbgiNC XkJMZps0dWQapa0Q5TtEhttPRnPP4PmItqVP090GPE5QZKEQ7B5TGa5mcs2dYpc+HY7U wZiuFx5ugcRASNmE5FZ5aveTj76PjSwPIUe5ErzXCZKx7Pe/hQaNknXsRtfQP+cZuGjI ZmsggSbWPP0T+C4sWoSAWkrAPr/96yiOujJ3s4mx/P/le8y5Zw+mchZayp1EdAsgtXY3 yPig== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=UPOdXwC1kuNdyAL0bf/AY2eNEz9jvw3Kld7w4EKJpxM=; b=stqLB3I+zJ1vS+lJWzlTz7cHoVGotEwfyQGNX1pvKV6UzE4BlIie9lT/LKnYcHefGv /q6GTLtF/bmP3ByKbbM2LyucTyLfOkPoGgE4DF3qp9V1GNV3yzto3a4yNYZnVLq+lI97 7iXxSL0kJYzOHYo7eW6bM0Db9x0S7EIrTG/C33YRQPWvapZyJYiFSFW9QxylPELyzZUj pGYTD5Cwr0h+NcpEpx4YMUCot/AvDd4usOgfR58rA99OmJ7mE1uEZRwV2YVk8athwhLg NzDAkxGLoFmSzr2ucjBnY3O4LdnKq480U9cfdz6VZlihVY2IPPRsz34Er0eB9Vaw5nW2 5vlA== X-Gm-Message-State: AOAM53132KG2V+4Yd9BFsxwDrj4gJnYcPfEmtl04qLABD5/SRuyuiYjB ZyzNEYjFAkJN9eSjJJ8b2i9uVg== X-Google-Smtp-Source: ABdhPJyIj3fDaYmUIQX/uw8tcvHB9NzVYpyZzpFcI/AI2ErDnN54sQMR/ofEq2b8Q3Wv/FT5h9L0AA== X-Received: by 2002:adf:e60a:: with SMTP id p10mr13905554wrm.306.1634302235499; Fri, 15 Oct 2021 05:50:35 -0700 (PDT) Received: from localhost.localdomain ([2a01:e0a:f:6020:7ce7:a27f:aba7:bb9d]) by smtp.gmail.com with ESMTPSA id a2sm5468403wrq.9.2021.10.15.05.50.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 15 Oct 2021 05:50:34 -0700 (PDT) From: Vincent Guittot To: mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, linux-kernel@vger.kernel.org, tim.c.chen@linux.intel.com Cc: Vincent Guittot Subject: [PATCH v2 3/4] sched/fair: Wait before decaying max_newidle_lb_cost Date: Fri, 15 Oct 2021 14:46:53 +0200 Message-Id: <20211015124654.18093-4-vincent.guittot@linaro.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20211015124654.18093-1-vincent.guittot@linaro.org> References: <20211015124654.18093-1-vincent.guittot@linaro.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Decay max_newidle_lb_cost only when it has not been updated for a while and ensure to not decay a recently changed value. Signed-off-by: Vincent Guittot --- include/linux/sched/topology.h | 2 +- kernel/sched/fair.c | 8 +++++--- kernel/sched/topology.c | 2 +- 3 files changed, 7 insertions(+), 5 deletions(-) diff --git a/include/linux/sched/topology.h b/include/linux/sched/topology.h index 8f0f778b7c91..9c8878f201ab 100644 --- a/include/linux/sched/topology.h +++ b/include/linux/sched/topology.h @@ -98,7 +98,7 @@ struct sched_domain { /* idle_balance() stats */ u64 max_newidle_lb_cost; - unsigned long next_decay_max_lb_cost; + unsigned long last_decay_max_lb_cost; u64 avg_scan_cost; /* select_idle_sibling */ diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 6b8065b72847..2967d13737b7 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -10265,10 +10265,10 @@ static void rebalance_domains(struct rq *rq, enum cpu_idle_type idle) * Decay the newidle max times here because this is a regular * visit to all the domains. Decay ~1% per second. */ - if (time_after(jiffies, sd->next_decay_max_lb_cost)) { + if (time_after(jiffies, sd->last_decay_max_lb_cost + HZ)) { sd->max_newidle_lb_cost = (sd->max_newidle_lb_cost * 253) / 256; - sd->next_decay_max_lb_cost = jiffies + HZ; + sd->last_decay_max_lb_cost = jiffies; need_decay = 1; } max_cost += sd->max_newidle_lb_cost; @@ -10912,8 +10912,10 @@ static int newidle_balance(struct rq *this_rq, struct rq_flags *rf) t1 = sched_clock_cpu(this_cpu); domain_cost = t1 - t0; - if (domain_cost > sd->max_newidle_lb_cost) + if (domain_cost > sd->max_newidle_lb_cost) { sd->max_newidle_lb_cost = domain_cost; + sd->last_decay_max_lb_cost = jiffies; + } curr_cost += domain_cost; t0 = t1; diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c index c56faae461d9..edd71649d579 100644 --- a/kernel/sched/topology.c +++ b/kernel/sched/topology.c @@ -1572,7 +1572,7 @@ sd_init(struct sched_domain_topology_level *tl, .last_balance = jiffies, .balance_interval = sd_weight, .max_newidle_lb_cost = 0, - .next_decay_max_lb_cost = jiffies, + .last_decay_max_lb_cost = jiffies, .child = child, #ifdef CONFIG_SCHED_DEBUG .name = tl->name, -- 2.17.1