From patchwork Tue Nov 21 13:44:25 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: 13463063 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.b="PUMuHBv/" 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 97C2E1721; Tue, 21 Nov 2023 05:44:40 -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=winLqcGTMq+SZizf/UjYofCIetGbvjNiBTRLKegVEMg=; b=PUMuHBv/SPVt12mWH7RCTV7yct rtAqDiaiK+G4xH0InybHlUIy2MghCYS9HSICK65UqkE7bZdyD+GgDNFCImlKtiyGh3OJSTHoqmk9G W3NgRgRXXDW92VmysYEVBLCHvFHjZY822RfhLQa/Vag9qZ8ztxtMjD7wlLC3utEX/nnRUHyeQMAUx KsC4Qxgbl+5QRb9orB4X5xzIGxyWgjnMu9jma0sMRIzIHmWcKs8fgqRlJEJKYue2gHUKYThSMSNkm UEpY5UM8Ak00vS2sIXu4bCYORzvzyeZU337wvBN74Xtd/OYs+xfhEkosJH0Flu+2VWGrBZZs64b23 jrpMiytg==; Received: from e0022681537dd.dyn.armlinux.org.uk ([fd8f:7570:feb6:1:222:68ff:fe15:37dd]:34688 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 1r5R3A-00077a-0H; Tue, 21 Nov 2023 13:44:24 +0000 Received: from rmk by rmk-PC.armlinux.org.uk with local (Exim 4.94.2) (envelope-from ) id 1r5R3B-00Csz6-Uh; Tue, 21 Nov 2023 13:44:25 +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 07/21] drivers: base: Allow parts of GENERIC_CPU_DEVICES to be overridden Precedence: bulk X-Mailing-List: linux-parisc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Disposition: inline Message-Id: Sender: Russell King Date: Tue, 21 Nov 2023 13:44:25 +0000 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 Reviewed-by: Shaoqin Huang Reviewed-by: Gavin Shan Signed-off-by: Russell King (Oracle) 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