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=-8.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 1FFF9C432C3 for ; Wed, 13 Nov 2019 18:23:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 03C04206EE for ; Wed, 13 Nov 2019 18:23:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alien8.de header.i=@alien8.de header.b="VuoILmIm" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728236AbfKMSXO (ORCPT ); Wed, 13 Nov 2019 13:23:14 -0500 Received: from mail.skyhub.de ([5.9.137.197]:59134 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727112AbfKMSXO (ORCPT ); Wed, 13 Nov 2019 13:23:14 -0500 Received: from zn.tnic (p200300EC2F0FA700D5A2A5422FC158AE.dip0.t-ipconnect.de [IPv6:2003:ec:2f0f:a700:d5a2:a542:2fc1:58ae]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id 9842B1EC0CDA; Wed, 13 Nov 2019 19:23:12 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1573669392; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:in-reply-to:in-reply-to: references:references; bh=UKGEADetohk5qnCPK5X+HcgpaPOf5iaScVD2zi3G9cU=; b=VuoILmImVGHmfiqvnbpZZdD8095ET1xkoBZuUD/WaoOUnEYmXBkCMNQM215PWj1wep434q ELIldMMtM5Xlw8zi4oOMie7xRpPgNDBXvqD6zL8OyBeH4x/XjYmayI9XegTsNfAlvyI6DW 6RZPN1xtkDS+I+buWAhVOUYnm3RlBr4= Date: Wed, 13 Nov 2019 19:23:07 +0100 From: Borislav Petkov To: Chen Yu Cc: x86@kernel.org, Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Reinette Chatre , Fenghua Yu , Tony Luck , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, Alexey Dobriyan , Andrew Morton , Michal Hocko , Linus Torvalds Subject: Re: [PATCH] x86/resctrl: Add task resctrl information display Message-ID: <20191113182306.GB1647@zn.tnic> References: <20191107032731.7790-1-yu.c.chen@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20191107032731.7790-1-yu.c.chen@intel.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Nov 07, 2019 at 11:27:31AM +0800, Chen Yu wrote: > Monitoring tools that want to find out which resctrl CTRL > and MONITOR groups a task belongs to must currently read > the "tasks" file in every group until they locate the process > ID. > > Add an additional file /proc/{pid}/resctrl to provide this > information. > > For example: > cat /proc/1193/resctrl > CTRL_MON:/ctrl_grp0 > MON:/ctrl_grp0/mon_groups/mon_grp0 > > If the resctrl filesystem has not been mounted, > reading /proc/{pid}/resctrl returns an error: > cat: /proc/1193/resctrl: No such device > > Tested-by: Jinshi Chen > Reviewed-by: Reinette Chatre > Reviewed-by: Fenghua Yu > Reviewed-by: Tony Luck > Signed-off-by: Chen Yu > > --- > arch/x86/include/asm/resctrl_sched.h | 4 +++ > arch/x86/kernel/cpu/resctrl/rdtgroup.c | 46 ++++++++++++++++++++++++++ > fs/proc/base.c | 9 +++++ ^^^^^^^^^^^^^^^ So you're touching this file here and yet your Cc list doesn't have *anyone* who might be responsible for the proc fs (yeah, you have linux-fsdevel but I don't think that's enough). Have you heard of scripts/get_maintainer.pl? Use it in the future. Cc-ing some more people for the generic /proc bits. > 3 files changed, 59 insertions(+) > > diff --git a/arch/x86/include/asm/resctrl_sched.h b/arch/x86/include/asm/resctrl_sched.h > index f6b7fe2833cc..bba362e0e00f 100644 > --- a/arch/x86/include/asm/resctrl_sched.h > +++ b/arch/x86/include/asm/resctrl_sched.h > @@ -5,6 +5,7 @@ > #ifdef CONFIG_X86_CPU_RESCTRL > > #include > +#include > #include > > #define IA32_PQR_ASSOC 0x0c8f > @@ -84,6 +85,9 @@ static inline void resctrl_sched_in(void) > __resctrl_sched_in(); > } > > +int proc_resctrl_show(struct seq_file *m, struct pid_namespace *ns, > + struct pid *pid, struct task_struct *tsk); > + > #else > > static inline void resctrl_sched_in(void) {} > diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c > index a46dee8e78db..2317174174e9 100644 > --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c > +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c > @@ -727,6 +727,52 @@ static int rdtgroup_tasks_show(struct kernfs_open_file *of, > return ret; > } > > +int proc_resctrl_show(struct seq_file *s, struct pid_namespace *ns, > + struct pid *pid, struct task_struct *tsk) > +{ > + struct rdtgroup *rdtg; > + int ret = 0; > + > + mutex_lock(&rdtgroup_mutex); > + > + /* Make sure resctrl has been mounted. */ > + if (!static_branch_unlikely(&rdt_enable_key)) { > + ret = -ENODEV; > + goto unlock; > + } > + > + list_for_each_entry(rdtg, &rdt_all_groups, rdtgroup_list) { > + struct rdtgroup *crg; > + > + /* > + * Task information is only relevant for shareable > + * and exclusive groups. > + */ > + if (rdtg->mode != RDT_MODE_SHAREABLE && > + rdtg->mode != RDT_MODE_EXCLUSIVE) > + continue; > + > + if (rdtg->closid == tsk->closid) { Save an indentation level: if (rdtg->closid != tsk->closid) continue; seq_printf... > + seq_printf(s, "CTRL_MON:/%s\n", rdtg->kn->name); > + list_for_each_entry(crg, &rdtg->mon.crdtgrp_list, > + mon.crdtgrp_list) { > + if (tsk->rmid != crg->mon.rmid) > + continue; > + seq_printf(s, "MON:%s%s/mon_groups/%s\n", > + rdtg == &rdtgroup_default ? "" : "/", > + rdtg->kn->name, crg->kn->name); > + goto unlock; > + } > + goto unlock; > + } > + } > + ret = -ENOENT; > +unlock: > + mutex_unlock(&rdtgroup_mutex); > + > + return ret; > +} > + > static int rdt_last_cmd_status_show(struct kernfs_open_file *of, > struct seq_file *seq, void *v) > { > diff --git a/fs/proc/base.c b/fs/proc/base.c > index ebea9501afb8..d8a61db78db5 100644 > --- a/fs/proc/base.c > +++ b/fs/proc/base.c > @@ -95,6 +95,9 @@ > #include > #include > #include > +#ifdef CONFIG_X86_CPU_RESCTRL > +#include > +#endif If anything, this should be abstracted nicely into an include/linux/resctrl.h header. Other architectures would probably wanna use it too, I hear ARM64 has something like resctrl. > #include "internal.h" > #include "fd.h" > > @@ -3060,6 +3063,9 @@ static const struct pid_entry tgid_base_stuff[] = { > #endif > #ifdef CONFIG_CGROUPS > ONE("cgroup", S_IRUGO, proc_cgroup_show), > +#endif > +#ifdef CONFIG_X86_CPU_RESCTRL > + ONE("resctrl", S_IRUGO, proc_resctrl_show), > #endif > ONE("oom_score", S_IRUGO, proc_oom_score), > REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adj_operations), > @@ -3460,6 +3466,9 @@ static const struct pid_entry tid_base_stuff[] = { > #endif > #ifdef CONFIG_CGROUPS > ONE("cgroup", S_IRUGO, proc_cgroup_show), > +#endif > +#ifdef CONFIG_X86_CPU_RESCTRL > + ONE("resctrl", S_IRUGO, proc_resctrl_show), > #endif Same here. proc_resctrl_show() looks like a generic function but it is x86-only. Need to call the x86-specific one in a real generic proc_resctrl_show() which other arches can add their code to, too. Not like that. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette