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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7861AC25B4E for ; Fri, 20 Jan 2023 16:41:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230370AbjATQlH (ORCPT ); Fri, 20 Jan 2023 11:41:07 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50290 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230084AbjATQlB (ORCPT ); Fri, 20 Jan 2023 11:41:01 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4CBC1F758 for ; Fri, 20 Jan 2023 08:40:11 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1674232810; 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:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=4sa2kw4N+EbeMvCkIPchCu6oDfnzvOZL2pa2xR/ZSFc=; b=XxTFiFxZRgSRUId3b3xP/WlrKpiyJBvCP6cUM7U9IcDZ+QwcedOH/X6TFrIPCNC4FjEygj 5+M3/7wdwRyfhdYy8be4LzYDaxiHgWOPPOBv/Yc14JeJSsm3xTXBkaAsXX4w5Ktsh/ZaLC vQbtzK5Xr3pHEM2IAQfpgGPQYnSIjF4= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-671-hXXltTvEOE6UVgGb0Gik3w-1; Fri, 20 Jan 2023 11:33:32 -0500 X-MC-Unique: hXXltTvEOE6UVgGb0Gik3w-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 848E5811E6E; Fri, 20 Jan 2023 16:33:31 +0000 (UTC) Received: from pauld.bos.com (dhcp-17-237.bos.redhat.com [10.18.17.237]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3A263140EBF6; Fri, 20 Jan 2023 16:33:31 +0000 (UTC) From: Phil Auld To: linux-kernel@vger.kernel.org Cc: pauld@redhat.com, gregkh@linuxfoundation.org, mingo@redhat.com, peterz@infradead.org, ritesh.list@gmail.com, srikar@linux.vnet.ibm.com, sshegde@linux.ibm.com, vincent.guittot@linaro.org, vishalc@linux.vnet.ibm.com, vschneid@redhat.com Subject: [PATCH v2] sched/debug: Put sched/domains files under the verbose flag Date: Fri, 20 Jan 2023 11:33:30 -0500 Message-Id: <20230120163330.1334128-1-pauld@redhat.com> In-Reply-To: <20230119150758.880189-1-pauld@redhat.com> References: <20230119150758.880189-1-pauld@redhat.com> MIME-Version: 1.0 Content-type: text/plain Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.1 on 10.11.54.7 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The debug files under sched/domains can take a long time to regenerate, especially when updates are done one at a time. Move these files under the sched verbose debug flag. Allow changes to verbose to trigger generation of the files. This lets a user batch the updates but still have the information available. The detailed topology printk messages are also under verbose. Discussion that lead to this approach can be found in the link below. Simplified code to maintain use of debugfs bool routines suggested by Michael Ellerman . Signed-off-by: Phil Auld Cc: Michael Ellerman Cc: Greg Kroah-Hartman Cc: Ingo Molnar Cc: Peter Zijlstra (Intel) Cc: Srikar Dronamraju Cc: Valentin Schneider Cc: Vishal Chourasia Cc: Vincent Guittot Link: https://lore.kernel.org/all/Y01UWQL2y2r69sBX@li-05afa54c-330e-11b2-a85c-e3f3aa0db1e9.ibm.com/ --- v2: fix comment typo and use cpumask_empty() kernel/sched/debug.c | 52 +++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 49 insertions(+), 3 deletions(-) diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c index 1637b65ba07a..0b2340a79b65 100644 --- a/kernel/sched/debug.c +++ b/kernel/sched/debug.c @@ -280,6 +280,45 @@ static const struct file_operations sched_dynamic_fops = { __read_mostly bool sched_debug_verbose; +#ifdef CONFIG_SMP +static struct dentry *sd_dentry; + + +static ssize_t sched_verbose_write(struct file *filp, const char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + ssize_t result; + bool orig; + + cpus_read_lock(); + mutex_lock(&sched_domains_mutex); + + orig = sched_debug_verbose; + result = debugfs_write_file_bool(filp, ubuf, cnt, ppos); + + if (sched_debug_verbose && !orig) + update_sched_domain_debugfs(); + else if (!sched_debug_verbose && orig) { + debugfs_remove(sd_dentry); + sd_dentry = NULL; + } + + mutex_unlock(&sched_domains_mutex); + cpus_read_unlock(); + + return result; +} +#else +#define sched_verbose_write debugfs_write_file_bool +#endif + +static const struct file_operations sched_verbose_fops = { + .read = debugfs_read_file_bool, + .write = sched_verbose_write, + .open = simple_open, + .llseek = default_llseek, +}; + static const struct seq_operations sched_debug_sops; static int sched_debug_open(struct inode *inode, struct file *filp) @@ -303,7 +342,7 @@ static __init int sched_init_debug(void) debugfs_sched = debugfs_create_dir("sched", NULL); debugfs_create_file("features", 0644, debugfs_sched, NULL, &sched_feat_fops); - debugfs_create_bool("verbose", 0644, debugfs_sched, &sched_debug_verbose); + debugfs_create_file_unsafe("verbose", 0644, debugfs_sched, &sched_debug_verbose, &sched_verbose_fops); #ifdef CONFIG_PREEMPT_DYNAMIC debugfs_create_file("preempt", 0644, debugfs_sched, NULL, &sched_dynamic_fops); #endif @@ -345,7 +384,6 @@ late_initcall(sched_init_debug); #ifdef CONFIG_SMP static cpumask_var_t sd_sysctl_cpus; -static struct dentry *sd_dentry; static int sd_flags_show(struct seq_file *m, void *v) { @@ -402,15 +440,23 @@ void update_sched_domain_debugfs(void) if (!debugfs_sched) return; + if (!sched_debug_verbose) + return; + if (!cpumask_available(sd_sysctl_cpus)) { if (!alloc_cpumask_var(&sd_sysctl_cpus, GFP_KERNEL)) return; cpumask_copy(sd_sysctl_cpus, cpu_possible_mask); } - if (!sd_dentry) + if (!sd_dentry) { sd_dentry = debugfs_create_dir("domains", debugfs_sched); + /* rebuild sd_sysctl_cpus if empty since it gets cleared below */ + if (cpumask_empty(sd_sysctl_cpus)) + cpumask_copy(sd_sysctl_cpus, cpu_online_mask); + } + for_each_cpu(cpu, sd_sysctl_cpus) { struct sched_domain *sd; struct dentry *d_cpu; -- 2.31.1