From patchwork Wed Feb 1 20:43:31 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Usama Arif X-Patchwork-Id: 13124976 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 8FC1EC636D7 for ; Wed, 1 Feb 2023 20:45:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231150AbjBAUpa (ORCPT ); Wed, 1 Feb 2023 15:45:30 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53408 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230225AbjBAUpV (ORCPT ); Wed, 1 Feb 2023 15:45:21 -0500 Received: from mail-wr1-x42d.google.com (mail-wr1-x42d.google.com [IPv6:2a00:1450:4864:20::42d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6A7F3783E7 for ; Wed, 1 Feb 2023 12:44:50 -0800 (PST) Received: by mail-wr1-x42d.google.com with SMTP id t7so10140611wrp.5 for ; Wed, 01 Feb 2023 12:44:50 -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=cVGzQu3A2f4Qgo78q6jxGuOz9gIN1MMwXavNYjSHKBU=; b=1pmygf+5X1mOOTRudl4VcLIfZwAStujjk3QFGa6j7KBal48TQf/affncmOD3//kkMI rcmGFccJCavXlkXytWAbcm6emsOHDwsjt6vCZUF43+rfAZGCQ79xzEj6NExy3AWl2TIH yqq4qgKbDrRXWSdk/Q6LTGijK2ZwPQRhSwcI44pdzEE7QTuapkzHDgxfAFcajF4pFeiU c+DydIzDTjs9qzHUYHbj4pjAqVKeSBkn3qUBcz10GgDBL1+qKVKQYV54cTXisUVhB59K zisPp3vUaSdjviwrmlQIpnH9yGM9tfJ3vGj1rRhx0PEZ2z+5ua/QBLLFDvzwKxEmVQh9 qy/g== 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=cVGzQu3A2f4Qgo78q6jxGuOz9gIN1MMwXavNYjSHKBU=; b=HormtI80XRX5wf3WyeDHWVvGpTLmgTsTp2RAtKZq6FBa3CINSQF6Cg5Z/Yf+VXP/Yw kp9KFfXmKa+2yggDEjehOLpjlIdmhZx2bNJWoX3+3DdrVQmNM3moAOU1S6XaCtX2YrW5 bVc2G4ksh07Zcv81Cba1MXadrt8xuh4buo16jffI71izFFJ33q6I6O30At4sKuKnt0ZD tIFg9cwUKiM3SnlfhspoiBVUwT2BGGZgoNxJRwmDlxiEcFTJCIiMRia4tpELmXgI/kyo fortjrfR6JcvX3aa+WLG0jISnV/5YIIWFqTL1S+WGWCfJs3ESlchfEQzpkjdj1qYmK6Q 3VRg== X-Gm-Message-State: AO0yUKUSsFdEdwBNs8Q9UCQMzgrByxQw8Sdf8tc++ejuxwlfZA+C6NwO 9cY7xk4XqMvnRHV3PQO3lIdQHQ== X-Google-Smtp-Source: AK7set8mJWiWAyJ74ti7VNQuSfGVVgfkF41VUhLW8nQG2B3Y90nuZ7EqdpXgzcSEUSguB8Fe2CwcUg== X-Received: by 2002:a05:6000:1004:b0:2bf:d332:e123 with SMTP id a4-20020a056000100400b002bfd332e123mr3000451wrx.62.1675284288852; Wed, 01 Feb 2023 12:44:48 -0800 (PST) Received: from usaari01.cust.communityfibre.co.uk ([2a02:6b6a:b566:0:7611:c340:3d8d:d46c]) by smtp.gmail.com with ESMTPSA id n15-20020a5d598f000000b002bdff778d87sm19993584wri.34.2023.02.01.12.44.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 01 Feb 2023 12:44:48 -0800 (PST) From: Usama Arif To: dwmw2@infradead.org, tglx@linutronix.de Cc: 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 Subject: [PATCH 2/9] cpu/hotplug: Move idle_thread_get() to Date: Wed, 1 Feb 2023 20:43:31 +0000 Message-Id: <20230201204338.1337562-3-usama.arif@bytedance.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230201204338.1337562-1-usama.arif@bytedance.com> References: <20230201204338.1337562-1-usama.arif@bytedance.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@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 --- 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