From patchwork Tue Nov 7 10:29:54 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Russell King \(Oracle\)" X-Patchwork-Id: 742172 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 9B6EFC04A68 for ; Tue, 7 Nov 2023 10:30:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234069AbjKGKab (ORCPT ); Tue, 7 Nov 2023 05:30:31 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40724 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233979AbjKGKaT (ORCPT ); Tue, 7 Nov 2023 05:30:19 -0500 Received: from pandora.armlinux.org.uk (pandora.armlinux.org.uk [IPv6:2001:4d48:ad52:32c8:5054:ff:fe00:142]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7003D10E5; Tue, 7 Nov 2023 02:30:14 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Date:Sender:Message-Id:Content-Type: Content-Transfer-Encoding:MIME-Version:Subject:Cc:To:From:References: In-Reply-To:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=Q80acMOYYyCsBO4DF+q5UzwIza1MpFhs36lmqhGxrto=; b=uYWeT36tOVZqQLHW8tNA+MO8rE NiPMKiW9gaelNRus/s5Ndwtp0uSmK/lvfdHkfE4QcP/onqrPhkLvgI35Ka5HmjSXEMAvbiYgMQVrl +R1eLD7PmsVjOI1TNlTNJRTsoWihSZNGPC8J/VQBlPMIKcPEChGWuQz77MLr+t/Uf5ufYUqvafSN0 7bG6U12ZWtCSTuitSJr5zW6rpcvmvn/XnQxS0bVmGJ5oE34UB2knVJ9Qi+6Hm9JyKYkj3TtsoxQ3H CuMUVTUeU2RvU6pywO/4Kxgjk0b+YaN9BUYz70gksgowZhGLmvsIhHdh7ATzTnUC7vy/yOGwcGPKT kUW8Cxeg==; Received: from e0022681537dd.dyn.armlinux.org.uk ([fd8f:7570:feb6:1:222:68ff:fe15:37dd]:41338 helo=rmk-PC.armlinux.org.uk) by pandora.armlinux.org.uk with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1r0JLN-0000F3-0m; Tue, 07 Nov 2023 10:30:03 +0000 Received: from rmk by rmk-PC.armlinux.org.uk with local (Exim 4.94.2) (envelope-from ) id 1r0JLG-00CTx8-CG; Tue, 07 Nov 2023 10:29:54 +0000 In-Reply-To: References: From: Russell King (Oracle) To: linux-pm@vger.kernel.org, loongarch@lists.linux.dev, linux-acpi@vger.kernel.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-riscv@lists.infradead.org, kvmarm@lists.linux.dev, x86@kernel.org, linux-csky@vger.kernel.org, linux-doc@vger.kernel.org, linux-ia64@vger.kernel.org, linux-parisc@vger.kernel.org Cc: Salil Mehta , Jean-Philippe Brucker , jianyong.wu@arm.com, justin.he@arm.com, James Morse , Greg Kroah-Hartman , "Rafael J. Wysocki" , Thomas Gleixner , Peter Zijlstra Subject: [PATCH RFC 07/22] drivers: base: Allow parts of GENERIC_CPU_DEVICES to be overridden MIME-Version: 1.0 Content-Disposition: inline Message-Id: Sender: Russell King Date: Tue, 07 Nov 2023 10:29:54 +0000 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org From: James Morse Architectures often have extra per-cpu work that needs doing before a CPU is registered, often to determine if a CPU is hotpluggable. To allow the ACPI architectures to use GENERIC_CPU_DEVICES, move the cpu_register() call into arch_register_cpu(), which is made __weak so architectures with extra work can override it. This aligns with the way x86, ia64 and loongarch register hotplug CPUs when they become present. Signed-off-by: James Morse Signed-off-by: Russell King (Oracle) Reviewed-by: Shaoqin Huang Reviewed-by: Gavin Shan Reviewed-by: Jonathan Cameron --- Changes since RFC: * Dropped __init from x86/ia64 arch_register_cpu() Changes since RFC v2: * Dropped unnecessary Loongarch asm/cpu.h changes --- drivers/base/cpu.c | 14 ++++++++++---- include/linux/cpu.h | 4 ++++ 2 files changed, 14 insertions(+), 4 deletions(-) diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c index 34b48f660b6b..579064fda97b 100644 --- a/drivers/base/cpu.c +++ b/drivers/base/cpu.c @@ -525,19 +525,25 @@ bool cpu_is_hotpluggable(unsigned int cpu) EXPORT_SYMBOL_GPL(cpu_is_hotpluggable); #ifdef CONFIG_GENERIC_CPU_DEVICES -static DEFINE_PER_CPU(struct cpu, cpu_devices); +DEFINE_PER_CPU(struct cpu, cpu_devices); + +int __weak arch_register_cpu(int cpu) +{ + return register_cpu(&per_cpu(cpu_devices, cpu), cpu); +} #endif static void __init cpu_dev_register_generic(void) { -#ifdef CONFIG_GENERIC_CPU_DEVICES int i; + if (!IS_ENABLED(CONFIG_GENERIC_CPU_DEVICES)) + return; + for_each_present_cpu(i) { - if (register_cpu(&per_cpu(cpu_devices, i), i)) + if (arch_register_cpu(i)) panic("Failed to register CPU device"); } -#endif } #ifdef CONFIG_GENERIC_CPU_VULNERABILITIES diff --git a/include/linux/cpu.h b/include/linux/cpu.h index fc8094419084..1e982d63eae8 100644 --- a/include/linux/cpu.h +++ b/include/linux/cpu.h @@ -88,6 +88,10 @@ extern ssize_t arch_cpu_probe(const char *, size_t); extern ssize_t arch_cpu_release(const char *, size_t); #endif +#ifdef CONFIG_GENERIC_CPU_DEVICES +DECLARE_PER_CPU(struct cpu, cpu_devices); +#endif + /* * These states are not related to the core CPU hotplug mechanism. They are * used by various (sub)architectures to track internal state