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 X-Spam-Level: X-Spam-Status: No, score=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT 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 14254C35666 for ; Sun, 23 Feb 2020 19:32:55 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8284720836 for ; Sun, 23 Feb 2020 19:32:54 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8284720836 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 48Qb2D0qSpzDqR6 for ; Mon, 24 Feb 2020 06:32:52 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=arm.com (client-ip=217.140.110.172; helo=foss.arm.com; envelope-from=qais.yousef@arm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=arm.com Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lists.ozlabs.org (Postfix) with ESMTP id 48QZys2fRhzDqBW for ; Mon, 24 Feb 2020 06:29:55 +1100 (AEDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 3D692101E; Sun, 23 Feb 2020 11:29:54 -0800 (PST) Received: from e107158-lin.cambridge.arm.com (e107158-lin.cambridge.arm.com [10.1.195.21]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 437293F6CF; Sun, 23 Feb 2020 11:29:52 -0800 (PST) From: Qais Yousef To: Thomas Gleixner Subject: [PATCH v3 01/15] cpu: Add new {add,remove}_cpu() functions Date: Sun, 23 Feb 2020 19:29:28 +0000 Message-Id: <20200223192942.18420-2-qais.yousef@arm.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200223192942.18420-1-qais.yousef@arm.com> References: <20200223192942.18420-1-qais.yousef@arm.com> X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Juergen Gross , Mark Rutland , Lorenzo Pieralisi , linux-parisc@vger.kernel.org, "Paul E . McKenney" , Helge Deller , x86@kernel.org, linux-kernel@vger.kernel.org, "David S. Miller" , sparclinux@vger.kernel.org, xen-devel@lists.xenproject.org, linuxppc-dev@lists.ozlabs.org, Qais Yousef , linux-arm-kernel@lists.infradead.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" The new functions use device_{online,offline}() which are userspace safe. This is in preparation to move cpu_{up, down} kernel users to use a safer interface that is not racy with userspace. Suggested-by: "Paul E. McKenney" Signed-off-by: Qais Yousef CC: Thomas Gleixner CC: "Paul E. McKenney" CC: Helge Deller CC: Michael Ellerman CC: "David S. Miller" CC: Juergen Gross CC: Mark Rutland CC: Lorenzo Pieralisi CC: xen-devel@lists.xenproject.org CC: linux-parisc@vger.kernel.org CC: sparclinux@vger.kernel.org CC: linuxppc-dev@lists.ozlabs.org CC: linux-arm-kernel@lists.infradead.org CC: x86@kernel.org CC: linux-kernel@vger.kernel.org --- include/linux/cpu.h | 2 ++ kernel/cpu.c | 24 ++++++++++++++++++++++++ 2 files changed, 26 insertions(+) diff --git a/include/linux/cpu.h b/include/linux/cpu.h index 1ca2baf817ed..cf8cf38dca43 100644 --- a/include/linux/cpu.h +++ b/include/linux/cpu.h @@ -89,6 +89,7 @@ extern ssize_t arch_cpu_release(const char *, size_t); #ifdef CONFIG_SMP extern bool cpuhp_tasks_frozen; int cpu_up(unsigned int cpu); +int add_cpu(unsigned int cpu); void notify_cpu_starting(unsigned int cpu); extern void cpu_maps_update_begin(void); extern void cpu_maps_update_done(void); @@ -118,6 +119,7 @@ extern void cpu_hotplug_disable(void); extern void cpu_hotplug_enable(void); void clear_tasks_mm_cpumask(int cpu); int cpu_down(unsigned int cpu); +int remove_cpu(unsigned int cpu); #else /* CONFIG_HOTPLUG_CPU */ diff --git a/kernel/cpu.c b/kernel/cpu.c index 9c706af713fb..069802f7010f 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -1057,6 +1057,18 @@ int cpu_down(unsigned int cpu) } EXPORT_SYMBOL(cpu_down); +int remove_cpu(unsigned int cpu) +{ + int ret; + + lock_device_hotplug(); + ret = device_offline(get_cpu_device(cpu)); + unlock_device_hotplug(); + + return ret; +} +EXPORT_SYMBOL_GPL(remove_cpu); + #else #define takedown_cpu NULL #endif /*CONFIG_HOTPLUG_CPU*/ @@ -1209,6 +1221,18 @@ int cpu_up(unsigned int cpu) } EXPORT_SYMBOL_GPL(cpu_up); +int add_cpu(unsigned int cpu) +{ + int ret; + + lock_device_hotplug(); + ret = device_online(get_cpu_device(cpu)); + unlock_device_hotplug(); + + return ret; +} +EXPORT_SYMBOL_GPL(add_cpu); + #ifdef CONFIG_PM_SLEEP_SMP static cpumask_var_t frozen_cpus; -- 2.17.1