From patchwork Thu Feb 2 21:56:16 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Usama Arif X-Patchwork-Id: 13126761 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 75BF9C636D3 for ; Thu, 2 Feb 2023 21:57:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233206AbjBBV5Y (ORCPT ); Thu, 2 Feb 2023 16:57:24 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54786 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232285AbjBBV5L (ORCPT ); Thu, 2 Feb 2023 16:57:11 -0500 Received: from mail-wr1-x429.google.com (mail-wr1-x429.google.com [IPv6:2a00:1450:4864:20::429]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D7F1268AD0 for ; Thu, 2 Feb 2023 13:56:33 -0800 (PST) Received: by mail-wr1-x429.google.com with SMTP id t7so3002684wrp.5 for ; Thu, 02 Feb 2023 13:56:33 -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=fGUMPbv5ehkWjyJkrcI0+C5Cz30zQDLH70pUeAdBLkQ=; b=2M4JOPBXhf4n8GQQdyrzHe3qWIJaL7f9plv5S3ltmqAiKFtsvcGXGUTC2Zuij3BMbs HhlEqG9+INFdfdUkReFlmvH2JPZMrNCztu3WfOAY+06RdcFUOlBB41XvMs68Ya736yK2 nOZn1J7hYgH42tp/gN4crt3m2pxOLEjJAusMRXcc680eWWrSJLJMCjmPufzsVttIRkCW 9QkU3r7GppcN34bu8GaPenanJDgtpVPDONSrvDRiSQXJXkEZApH8tlqbG9jFp0sxPyy2 H0xXvJvm2qthioHCwmimhIU+Q9Nh8Kc7h/9OaMxXMAdSlKwy88YLZFA1gae6hbRvVar+ bsdg== 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=fGUMPbv5ehkWjyJkrcI0+C5Cz30zQDLH70pUeAdBLkQ=; b=qmMkdFVtjmIsPvX0beHs3s8j1GlfPKN5k9GAKT8jKyZYm4lqMlAVJmgCwiW/MbVyEX N2OkEX2Qpp4NfQ22GddSk6DaqzSKkoVj9fgmqB09D3EqRgHG5+Q/+16aMufVTftGjSz1 zyOy+cIFcdGiPDdR1TmIispltauD3bhag30DZYDtF3hwjwr72mOhfcwYQQSXdp6HoSPd eWuDlV2z5XU7CEM+d4P1l2fhZRHBdNo6qxTRl6G/RtZtvRuh1Ce8dbpvI54W5CCRR9Nf vUjT2XxYqW5GvBaKKY333QujDhGeVUbaqp27Vv3fZuVH7OX0j57Z3KRLElH6XCRdbmzg hc+w== X-Gm-Message-State: AO0yUKWyO4lf2V3vU4IHsDe1o9gj1koN/G7xgw0obbbzne3qC+mGLG+8 tJOM3rpp7AClY8yescPLqNpC1w== X-Google-Smtp-Source: AK7set/CDswZdmTsSZsErF7V63uar9uvceQgDgLkLPtGwcWkpo8b1nJ0th3Lj0DuhHf/pnavpwsO/g== X-Received: by 2002:a5d:6c6d:0:b0:2bf:d6f9:23d6 with SMTP id r13-20020a5d6c6d000000b002bfd6f923d6mr7783377wrz.45.1675374992316; Thu, 02 Feb 2023 13:56:32 -0800 (PST) Received: from usaari01.cust.communityfibre.co.uk ([2a02:6b6a:b566:0:98fe:e4ee:fc7e:cd71]) by smtp.gmail.com with ESMTPSA id e8-20020a5d6d08000000b00297dcfdc90fsm506078wrq.24.2023.02.02.13.56.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 02 Feb 2023 13:56:31 -0800 (PST) From: Usama Arif To: dwmw2@infradead.org, tglx@linutronix.de, arjan@linux.intel.com 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 v6 02/11] cpu/hotplug: Move idle_thread_get() to Date: Thu, 2 Feb 2023 21:56:16 +0000 Message-Id: <20230202215625.3248306-3-usama.arif@bytedance.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230202215625.3248306-1-usama.arif@bytedance.com> References: <20230202215625.3248306-1-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 Signed-off-by: Paul E. McKenney Reviewed-by: Thomas Gleixner --- 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