From patchwork Tue Oct 24 15:17:26 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: 13434873 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 3BBEAC07545 for ; Tue, 24 Oct 2023 15:18:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Date:Message-Id: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-Owner; bh=02jaC+eSZAsHS8cQ9uq1vWH2bX98Zh0/OsjlCb8mqQI=; b=0AGVPAReG3gTFR vqz6cyVzzk5JskpIAX8Y1/TKPjTnlpwPy2qEDhpmRUDtBcTeVKh9YRduPNgmF0BJdyT3/+Vj4pzE4 XqJTqE2Sh47Ea29axqoZdH51FxuA7Db5Y+OEwKmsojbxSnNimXEzuBamMkKlpJx4QhEoStZPXW9Sw sYY4eD98RqePqdcHnHEFdyydCz5dbexd5btUTlAs5yuIPbpjjttYDS3leZddyM7nH/M4sq5kJED1j YcrdF4yeRy/rNaMfYIHczwSMKP3tCs8pATbNuadjxLFzDz5oc73gwXBguJ1M4ZkEsT8u/5hGstrPb muFsxp2W6Om/tYRUK/Iw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qvJAk-00AGCW-1a; Tue, 24 Oct 2023 15:18:22 +0000 Received: from pandora.armlinux.org.uk ([2001:4d48:ad52:32c8:5054:ff:fe00:142]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1qvJA3-00AFV0-1F; Tue, 24 Oct 2023 15:17:43 +0000 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=CjScRbjimPWolEjPv1iNmcYG5tuVKE74LVx0kYeqVqg=; b=vWxJVtsg7WAxV+31eW086kiVVz +Nfq4GNnO/goU36WX82JXeCpyz1NRsTtPu+wCbSUfXCIxDEs8V2oWVRggK16YBGzFFxeQ+OnMmZJx SKduHKqxOYaitZ5qSYpjaCC0mvbjdemJ7HST9R8ycAJWqs8qXQ/6cjIBtkPQnUeXcUewNThjp+aOB 3aqMMgcdALK6mkVwT0lgVBdBJKtVLR6yPuBhyST5VM/0eclmOmMma1u7G/bGi/oWtm9qAcpwTa/tA rxS9YGk4y0z9idXXB4mRIJ5H2iWjMlEX9mJu2motC/v1mbTTHrodN2WdAL7T9Y+SC/cMdxPfwyp5P 9dxgHRjw==; Received: from e0022681537dd.dyn.armlinux.org.uk ([fd8f:7570:feb6:1:222:68ff:fe15:37dd]:34774 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 1qvJ9o-0004Pd-3B; Tue, 24 Oct 2023 16:17:25 +0100 Received: from rmk by rmk-PC.armlinux.org.uk with local (Exim 4.94.2) (envelope-from ) id 1qvJ9q-00AqQI-F8; Tue, 24 Oct 2023 16:17:26 +0100 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 , Huacai Chen , WANG Xuerui Subject: [PATCH 15/39] LoongArch: Switch over to GENERIC_CPU_DEVICES MIME-Version: 1.0 Content-Disposition: inline Message-Id: Date: Tue, 24 Oct 2023 16:17:26 +0100 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20231024_081739_447029_9F939938 X-CRM114-Status: GOOD ( 14.69 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: James Morse Now that GENERIC_CPU_DEVICES calls arch_register_cpu(), which can be overridden by the arch code, switch over to this to allow common code to choose when the register_cpu() call is made. This allows topology_init() to be removed. This is an intermediate step to the logic being moved to drivers/acpi, where GENERIC_CPU_DEVICES will do the work when booting with acpi=off. This is a subtle change. Originally: - on boot, topology_init() would have marked present CPUs that io_master() is true for as hotplug-incapable. - if a CPU is hotplugged that is an io_master(), it can later be hot-unplugged. The new behaviour is that any CPU that io_master() is true for will now always be marked as hotplug-incapable, thus even if it was hotplugged, it can no longer be hot-unplugged. This patch also has the effect of moving the registration of CPUs from subsys to driver core initialisation, prior to any initcalls running. Signed-off-by: James Morse Signed-off-by: Russell King (Oracle) --- Changes since RFC v2: * Explain the change in behaviour in the patch description (highlighted by Jonathan Cameron - thanks.) Add note about initialisation order change. --- arch/loongarch/Kconfig | 1 + arch/loongarch/kernel/topology.c | 29 ++--------------------------- 2 files changed, 3 insertions(+), 27 deletions(-) diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig index 2bddd202470e..5bed51adc68c 100644 --- a/arch/loongarch/Kconfig +++ b/arch/loongarch/Kconfig @@ -72,6 +72,7 @@ config LOONGARCH select GENERIC_CLOCKEVENTS select GENERIC_CMOS_UPDATE select GENERIC_CPU_AUTOPROBE + select GENERIC_CPU_DEVICES select GENERIC_ENTRY select GENERIC_GETTIMEOFDAY select GENERIC_IOREMAP if !ARCH_IOREMAP diff --git a/arch/loongarch/kernel/topology.c b/arch/loongarch/kernel/topology.c index 3fd166006698..bf58351beac1 100644 --- a/arch/loongarch/kernel/topology.c +++ b/arch/loongarch/kernel/topology.c @@ -10,20 +10,13 @@ #include -static DEFINE_PER_CPU(struct cpu, cpu_devices); - #ifdef CONFIG_HOTPLUG_CPU int arch_register_cpu(int cpu) { - int ret; struct cpu *c = &per_cpu(cpu_devices, cpu); - c->hotpluggable = 1; - ret = register_cpu(c, cpu); - if (ret < 0) - pr_warn("register_cpu %d failed (%d)\n", cpu, ret); - - return ret; + c->hotpluggable = !io_master(cpu); + return register_cpu(c, cpu); } EXPORT_SYMBOL(arch_register_cpu); @@ -36,21 +29,3 @@ void arch_unregister_cpu(int cpu) } EXPORT_SYMBOL(arch_unregister_cpu); #endif - -static int __init topology_init(void) -{ - int i, ret; - - for_each_present_cpu(i) { - struct cpu *c = &per_cpu(cpu_devices, i); - - c->hotpluggable = !io_master(i); - ret = register_cpu(c, i); - if (ret < 0) - pr_warn("topology_init: register_cpu %d failed (%d)\n", i, ret); - } - - return 0; -} - -subsys_initcall(topology_init);