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=-18.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL 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 DE3C1C433B4 for ; Tue, 18 May 2021 18:56:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BD8F06135B for ; Tue, 18 May 2021 18:56:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245037AbhERS5a (ORCPT ); Tue, 18 May 2021 14:57:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59612 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236295AbhERS5a (ORCPT ); Tue, 18 May 2021 14:57:30 -0400 Received: from mail-yb1-xb35.google.com (mail-yb1-xb35.google.com [IPv6:2607:f8b0:4864:20::b35]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F2919C061760 for ; Tue, 18 May 2021 11:56:11 -0700 (PDT) Received: by mail-yb1-xb35.google.com with SMTP id g38so14647726ybi.12 for ; Tue, 18 May 2021 11:56:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=U5LLkV364fFy+W60IIkSO6ynttP+rk35+EuRn6ckGs8=; b=cxprohY/XMTUx1TEQw8jbzPmXFucnMNA2eyWUf19LpmAQx4UNLsmqbHDZHdjS/CaGr t03JLmDOtp4Xg8I94GL554PMO32h1RtbAqafRiUuHeVq0UM4yvTJUOloXYB06ANBfGoL jHHUFpm3nc2I9VvFuOTc16xcLvyF/tSSQeTmyKXCLvcacBJg/QcxMiYoGjz3FPLCq2i4 yYN8KkaSHTDa9C4UeiuwVYyH/i+SWrdUN9pY85oTs04kt0M7iKY9mN+soWEbt1EI4dpk edMxfCj+tyiAfv6N8heO33kP/Uy2yt6kyaDwkgF3bgtxtw/079Q1Rsuq/cikCVm577W8 /QhA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=U5LLkV364fFy+W60IIkSO6ynttP+rk35+EuRn6ckGs8=; b=Xa4mgVss1TCAwvb6NNjCbFtGo2ckwtwDW3oYBRMmVMUmC8A7ULUres67V8Vwmgom/P Zv9eoBbDlVXtvvnSrD0pVhzIFhPF4asJFfecFs4kJSp4u/ZRU1DSDgLTHJn7yb6SEgtL 9kOkXfi+lvQDnDGbaLXygNUAW09iP6+CgMKfZjhWSlMwZGUfMoXDjBTmQxmDkSYydQgy qjy26ihZd9e074o10GiaKTH8CcEp0Vig23LcMTqoEGtrCRmt23+wp2MSOTX0jm8ptgZ8 Pu/+dR1+DhobC4GrdwHySn4s6kYUKl8WC8WvH/Kl95PrRNfJNfFQb8FLy1/uLuIoplTK e49w== X-Gm-Message-State: AOAM532syfQA6Fduxf0kXfVD2aA1w/FN6ebit4CoK8gz/6cD9rSmsY9D WbkHLLSui4lxGOJ4TjFzCuQPwCOz8OTfXmg45tKcjw== X-Google-Smtp-Source: ABdhPJw+r9Vs8W/wHNhLBVF/L2/v9zN6CWY6uzHU1K20kYiRC4gsip28a5tC3+Qqg8OJDi8hfcKE77la5Q0Nvw9ThKI= X-Received: by 2002:a25:7ec4:: with SMTP id z187mr9138416ybc.136.1621364170924; Tue, 18 May 2021 11:56:10 -0700 (PDT) MIME-Version: 1.0 References: <20210518020200.1790058-1-surenb@google.com> <20210518185251.GI5618@worktop.programming.kicks-ass.net> In-Reply-To: <20210518185251.GI5618@worktop.programming.kicks-ass.net> From: Suren Baghdasaryan Date: Tue, 18 May 2021 11:55:59 -0700 Message-ID: Subject: Re: [PATCH v2 1/1] cgroup: make per-cgroup pressure stall tracking configurable To: Peter Zijlstra Cc: Tejun Heo , Johannes Weiner , Zefan Li , Ingo Molnar , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Benjamin Segall , Mel Gorman , Minchan Kim , Jonathan Corbet , Daniel Bristot de Oliveira , "Paul E . McKenney" , Randy Dunlap , Andrew Morton , Thomas Gleixner , macro@orcam.me.uk, Viresh Kumar , Mike Kravetz , linux-doc@vger.kernel.org, LKML , cgroups mailinglist , kernel-team Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org On Tue, May 18, 2021 at 11:52 AM Peter Zijlstra wrote: > > On Mon, May 17, 2021 at 07:02:00PM -0700, Suren Baghdasaryan wrote: > > > diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c > > index cc25a3cff41f..4b8e72640ac9 100644 > > --- a/kernel/sched/psi.c > > +++ b/kernel/sched/psi.c > > @@ -148,6 +148,7 @@ > > static int psi_bug __read_mostly; > > > > DEFINE_STATIC_KEY_FALSE(psi_disabled); > > +DEFINE_STATIC_KEY_FALSE(psi_cgroups_disabled); > > I'm thinking the whole thing will be easier/clearer when you make this: > > DEFINE_STATIC_KEY_TRUE(psi_cgroups_enabled); > Sounds good. Will respin another version. Thanks for reviewing! > > > > #ifdef CONFIG_PSI_DEFAULT_DISABLED > > static bool psi_enable; > > @@ -211,6 +212,9 @@ void __init psi_init(void) > > return; > > } > > > > + if (!cgroup_psi_enabled()) > > + static_branch_enable(&psi_cgroups_disabled); > > if (!cgroup_psi_enabled()) > static_branch_disable(&psi_cgroups_enabled); > > > + > > psi_period = jiffies_to_nsecs(PSI_FREQ); > > group_init(&psi_system); > > } > > @@ -744,23 +748,23 @@ static void psi_group_change(struct psi_group *group, int cpu, > > > > static struct psi_group *iterate_groups(struct task_struct *task, void **iter) > > { > > + if (*iter == &psi_system) > > + return NULL; > > + > > #ifdef CONFIG_CGROUPS > > + if (!static_branch_likely(&psi_cgroups_disabled)) { > > if (static_branch_likely(&psi_cgroups_enabled)) { > > > + struct cgroup *cgroup = NULL; > > > > + if (!*iter) > > + cgroup = task->cgroups->dfl_cgrp; > > + else > > + cgroup = cgroup_parent(*iter); > > > > + if (cgroup && cgroup_parent(cgroup)) { > > + *iter = cgroup; > > + return cgroup_psi(cgroup); > > + } > > } > > #endif > > *iter = &psi_system; > > return &psi_system; > > But yes, very nice. > > -- > To unsubscribe from this group and stop receiving emails from it, send an email to kernel-team+unsubscribe@android.com. >