From patchwork Fri Sep 25 18:26:51 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nitesh Narayan Lal X-Patchwork-Id: 260196 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=-11.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS autolearn=unavailable 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 C2B2CC47420 for ; Fri, 25 Sep 2020 18:27:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7E97A208A9 for ; Fri, 25 Sep 2020 18:27:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="dgpuCv+8" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729740AbgIYS1O (ORCPT ); Fri, 25 Sep 2020 14:27:14 -0400 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:30032 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729725AbgIYS1M (ORCPT ); Fri, 25 Sep 2020 14:27:12 -0400 Dkim-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1601058431; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:in-reply-to:in-reply-to:references:references; bh=iL0bUDw4mzTbRn0mPQir1H2iMDlMMQuuu3RzcEtjrtI=; b=dgpuCv+8dB6wxiu6EDvBDFqYvs+Rq3+h90h6S8oZKWh4C/vW4cToCXEsoX9c2pGZfSAYRL jENKoGxIRlnx/rIwWT3xHoXe7VhHC43uS1MhGs8fgWudsRXxLSjj79FUYg0/S+ASKv7wd6 VTxUxugKJTtsaGKv199QuVinsdoawm8= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-102-wptPqlM6OdSLHFgjXOJGwA-1; Fri, 25 Sep 2020 14:27:07 -0400 X-MC-Unique: wptPqlM6OdSLHFgjXOJGwA-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 6B23E1084C97; Fri, 25 Sep 2020 18:27:05 +0000 (UTC) Received: from virtlab719.virt.lab.eng.bos.redhat.com (virtlab719.virt.lab.eng.bos.redhat.com [10.19.153.15]) by smtp.corp.redhat.com (Postfix) with ESMTP id BA0A578831; Fri, 25 Sep 2020 18:27:03 +0000 (UTC) From: Nitesh Narayan Lal To: linux-kernel@vger.kernel.org, netdev@vger.kernel.org, linux-pci@vger.kernel.org, intel-wired-lan@lists.osuosl.org, frederic@kernel.org, mtosatti@redhat.com, sassmann@redhat.com, jesse.brandeburg@intel.com, lihong.yang@intel.com, helgaas@kernel.org, nitesh@redhat.com, jeffrey.t.kirsher@intel.com, jacob.e.keller@intel.com, jlelli@redhat.com, hch@infradead.org, bhelgaas@google.com, mike.marciniszyn@intel.com, dennis.dalessandro@intel.com, thomas.lendacky@amd.com, jiri@nvidia.com, mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, lgoncalv@redhat.com Subject: [PATCH v3 1/4] sched/isolation: API to get number of housekeeping CPUs Date: Fri, 25 Sep 2020 14:26:51 -0400 Message-Id: <20200925182654.224004-2-nitesh@redhat.com> In-Reply-To: <20200925182654.224004-1-nitesh@redhat.com> References: <20200925182654.224004-1-nitesh@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Introduce a new API housekeeping_num_online_cpus(), that can be used to retrieve the number of online housekeeping CPUs based on the housekeeping flag passed by the caller. Some of the consumers for this API are the device drivers that were previously relying only on num_online_cpus() to determine the number of MSIX vectors to create. In real-time environments to minimize interruptions to isolated CPUs, all device-specific IRQ vectors are often moved to the housekeeping CPUs, having excess vectors could cause housekeeping CPU to run out of IRQ vectors. Signed-off-by: Nitesh Narayan Lal --- include/linux/sched/isolation.h | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/include/linux/sched/isolation.h b/include/linux/sched/isolation.h index cc9f393e2a70..e021b1846c1d 100644 --- a/include/linux/sched/isolation.h +++ b/include/linux/sched/isolation.h @@ -57,4 +57,13 @@ static inline bool housekeeping_cpu(int cpu, enum hk_flags flags) return true; } +static inline unsigned int housekeeping_num_online_cpus(enum hk_flags flags) +{ +#ifdef CONFIG_CPU_ISOLATION + if (static_branch_unlikely(&housekeeping_overridden)) + return cpumask_weight(housekeeping_cpumask(flags)); +#endif + return num_online_cpus(); +} + #endif /* _LINUX_SCHED_ISOLATION_H */ From patchwork Fri Sep 25 18:26:52 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nitesh Narayan Lal X-Patchwork-Id: 260197 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=-11.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS 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 4BE28C4727E for ; Fri, 25 Sep 2020 18:27:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EA96B208A9 for ; Fri, 25 Sep 2020 18:27:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="eQucHJhx" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729756AbgIYS1P (ORCPT ); Fri, 25 Sep 2020 14:27:15 -0400 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:51091 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727495AbgIYS1M (ORCPT ); Fri, 25 Sep 2020 14:27:12 -0400 Dkim-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1601058431; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:in-reply-to:in-reply-to:references:references; bh=yrgq/KDevcEQJ6jt8mLwCRUIhO0cbeAMHgxfCLcgTj0=; b=eQucHJhxTzAFYrMf126p7iHOFLiqel4bOiWljTGYahNvmgWIZWac9RLXFaY5dYQuGfUpDf 5JIHtumHIrL8qeV0gaC63dljdmgB3isr07y8dFEfItRkyuEiaoKqaXckW8kWyIV4JV17pg 13/X59VDCZUNEye3CfhNE7rmEEoFJ7g= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-274-tQ7tu0ImMQCu12jq-NJWBw-1; Fri, 25 Sep 2020 14:27:09 -0400 X-MC-Unique: tQ7tu0ImMQCu12jq-NJWBw-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 363341084C96; Fri, 25 Sep 2020 18:27:07 +0000 (UTC) Received: from virtlab719.virt.lab.eng.bos.redhat.com (virtlab719.virt.lab.eng.bos.redhat.com [10.19.153.15]) by smtp.corp.redhat.com (Postfix) with ESMTP id 849337882D; Fri, 25 Sep 2020 18:27:05 +0000 (UTC) From: Nitesh Narayan Lal To: linux-kernel@vger.kernel.org, netdev@vger.kernel.org, linux-pci@vger.kernel.org, intel-wired-lan@lists.osuosl.org, frederic@kernel.org, mtosatti@redhat.com, sassmann@redhat.com, jesse.brandeburg@intel.com, lihong.yang@intel.com, helgaas@kernel.org, nitesh@redhat.com, jeffrey.t.kirsher@intel.com, jacob.e.keller@intel.com, jlelli@redhat.com, hch@infradead.org, bhelgaas@google.com, mike.marciniszyn@intel.com, dennis.dalessandro@intel.com, thomas.lendacky@amd.com, jiri@nvidia.com, mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, lgoncalv@redhat.com Subject: [PATCH v3 2/4] sched/isolation: Extend nohz_full to isolate managed IRQs Date: Fri, 25 Sep 2020 14:26:52 -0400 Message-Id: <20200925182654.224004-3-nitesh@redhat.com> In-Reply-To: <20200925182654.224004-1-nitesh@redhat.com> References: <20200925182654.224004-1-nitesh@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Extend nohz_full feature set to include isolation from managed IRQS. This is required specifically for setups that only uses nohz_full and still requires isolation for maintaining lower latency for the listed CPUs. Suggested-by: Frederic Weisbecker Signed-off-by: Nitesh Narayan Lal --- kernel/sched/isolation.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/sched/isolation.c b/kernel/sched/isolation.c index 5a6ea03f9882..9df9598a9e39 100644 --- a/kernel/sched/isolation.c +++ b/kernel/sched/isolation.c @@ -141,7 +141,7 @@ static int __init housekeeping_nohz_full_setup(char *str) unsigned int flags; flags = HK_FLAG_TICK | HK_FLAG_WQ | HK_FLAG_TIMER | HK_FLAG_RCU | - HK_FLAG_MISC | HK_FLAG_KTHREAD; + HK_FLAG_MISC | HK_FLAG_KTHREAD | HK_FLAG_MANAGED_IRQ; return housekeeping_setup(str, flags); }