From patchwork Thu Feb 9 15:41:49 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Usama Arif X-Patchwork-Id: 13134777 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 DB077C61DA4 for ; Thu, 9 Feb 2023 15:42:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231574AbjBIPml (ORCPT ); Thu, 9 Feb 2023 10:42:41 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54812 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231521AbjBIPmd (ORCPT ); Thu, 9 Feb 2023 10:42:33 -0500 Received: from mail-wm1-x331.google.com (mail-wm1-x331.google.com [IPv6:2a00:1450:4864:20::331]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F1B94303F2 for ; Thu, 9 Feb 2023 07:42:02 -0800 (PST) Received: by mail-wm1-x331.google.com with SMTP id u10so1721910wmj.3 for ; Thu, 09 Feb 2023 07:42:02 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20210112.gappssmtp.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=XKydoXD7DOLwoETiq1rVpdNfhGCr3/VFLGt4p4rSeXA=; b=2CVH9cp3pr0dhjoEe5Lh7i3BSbemsRr/OqAzKsploHApi7J03BEPBfBch4bLbqTSIA pjBpDpcdmOx7wc551tUDnwQOY6GyXzohRPqZ3VpIcB0CvhrwGpteU67ei1o2yD6q2eoq RxrEFY/smCKBaIyQa/vshAcR3v1M/3Y8CyZuY4LWwEjDq/KAxxSGVypXyMSXwS4Y6TKG M553wANc1uTwq1xbrCGxwwZrb3j381XzlyCd7cOS50+ujMsP4WKzO2/MfDzSIGGDwq6R DOFaT97zoZP3cBxt7kpar0m0CJVluRA+D1wcwNrF/zaNlwcFQ7IAp1MlcUzkkqgTz8gL uCrw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=XKydoXD7DOLwoETiq1rVpdNfhGCr3/VFLGt4p4rSeXA=; b=UYy7omNISpe6dTC2NaC89tRPHSx//PwnPMMoXZi9Afoyv24Z9SThTp/M1hiF0xIVAN Rb59dQxIs7SCJqYsoVwuy0y65YyYCVjXhq0Fu12uBg8nEKQwJy+wA84p2p/OESFc1het 9MVafASamyCO4TwNh1jYBOdmSRfUVN6zI3WTn5DYG/4YU3doCjVel9cAPbR01vZUFDP9 pZmZ96BUGuRBg20sbn5ly2WYAndPfMFywkXtE9g3QB6L2JKzEdaF/bguFeV8QOaRBPQ9 kvU+eyiHKgIDWWC3RMu2R4ibVI1XyIuqmEPcfMzwB8VGMFEBBheojqxTCsY99h7uxrEA ZEVQ== X-Gm-Message-State: AO0yUKWVHMB+u4vZ2dnCRJKnRYAjAVV38bHXmqmVUxvuId0UlnNYJ8LJ /FdsrOsVZZP6ayuVT3p225nevw== X-Google-Smtp-Source: AK7set9HcQn5njNfZ89WKBa5SFul8SUdp0kexugSeUAJLkuJUAocQZDht+khT1NSCYygFgM0B3hlaA== X-Received: by 2002:a05:600c:1713:b0:3da:fb3c:c1ab with SMTP id c19-20020a05600c171300b003dafb3cc1abmr10420659wmn.0.1675957321622; Thu, 09 Feb 2023 07:42:01 -0800 (PST) Received: from usaari01.cust.communityfibre.co.uk ([2a02:6b6a:b566:0:8009:2525:9580:8db2]) by smtp.gmail.com with ESMTPSA id y6-20020a05600c364600b003df7b40f99fsm5099754wmq.11.2023.02.09.07.42.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 09 Feb 2023 07:42:01 -0800 (PST) From: Usama Arif To: dwmw2@infradead.org, tglx@linutronix.de, kim.phillips@amd.com Cc: arjan@linux.intel.com, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, x86@kernel.org, pbonzini@redhat.com, paulmck@kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, rcu@vger.kernel.org, mimoja@mimoja.de, hewenliang4@huawei.com, thomas.lendacky@amd.com, seanjc@google.com, pmenzel@molgen.mpg.de, fam.zheng@bytedance.com, punit.agrawal@bytedance.com, simon.evans@bytedance.com, liangma@liangbit.com, David Woodhouse , Usama Arif Subject: [PATCH v8 2/9] cpu/hotplug: Move idle_thread_get() to Date: Thu, 9 Feb 2023 15:41:49 +0000 Message-Id: <20230209154156.266385-3-usama.arif@bytedance.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230209154156.266385-1-usama.arif@bytedance.com> References: <20230209154156.266385-1-usama.arif@bytedance.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: rcu@vger.kernel.org From: David Woodhouse Instead of relying purely on the special-case wrapper in bringup_cpu() to pass the idle thread to __cpu_up(), expose idle_thread_get() so that the architecture code can obtain it directly when necessary. This will be useful when the existing __cpu_up() is split into multiple phases, only *one* of which will actually need the idle thread. If the architecture code is to register its new pre-bringup states with the cpuhp core, having a special-case wrapper to pass extra arguments is non-trivial and it's easier just to let the arch register its function pointer to be invoked with the standard API. Signed-off-by: David Woodhouse Reviewed-by: Thomas Gleixner Signed-off-by: Usama Arif --- include/linux/smpboot.h | 7 +++++++ kernel/smpboot.h | 2 -- 2 files changed, 7 insertions(+), 2 deletions(-) diff --git a/include/linux/smpboot.h b/include/linux/smpboot.h index 9d1bc65d226c..3862addcaa34 100644 --- a/include/linux/smpboot.h +++ b/include/linux/smpboot.h @@ -5,6 +5,13 @@ #include struct task_struct; + +#ifdef CONFIG_GENERIC_SMP_IDLE_THREAD +struct task_struct *idle_thread_get(unsigned int cpu); +#else +static inline struct task_struct *idle_thread_get(unsigned int cpu) { return NULL; } +#endif + /* Cookie handed to the thread_fn*/ struct smpboot_thread_data; diff --git a/kernel/smpboot.h b/kernel/smpboot.h index 34dd3d7ba40b..60c609318ad6 100644 --- a/kernel/smpboot.h +++ b/kernel/smpboot.h @@ -5,11 +5,9 @@ struct task_struct; #ifdef CONFIG_GENERIC_SMP_IDLE_THREAD -struct task_struct *idle_thread_get(unsigned int cpu); void idle_thread_set_boot_cpu(void); void idle_threads_init(void); #else -static inline struct task_struct *idle_thread_get(unsigned int cpu) { return NULL; } static inline void idle_thread_set_boot_cpu(void) { } static inline void idle_threads_init(void) { } #endif