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 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 3C2FBC25B45 for ; Mon, 23 Oct 2023 20:02:40 +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:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=n1SYh5ltAMUxy7fhYiyry83Z6odYQNbauYLsjzAZi1s=; b=V0u5QqRglTdVti ug1XXzY3iwELUg27qEtKybkkCEagTzIdZUYpXWx6++7rQ6emZQ0wjABBTndRoy0tcdD86DSZySDTV +kFqtG7N/HIGsO6S8iNEVR4bBSR+9H/4nUc8ngkYjaj6YxBF8C3hVUABs2vye3ffR3bWzYRT0io0A GrTRgQHRStGhO/CoUZvu+zl3HidKk5jwMgh064arYN15rUFanSA46DZj8rBeg7IU2An/yS3h4E2YO s/SodFV83TjvJVNk2QZAphqtpDC4a4uth1X5HeuG+kj8wPDENyXOLS4InQcWsrOVGOC3QgfSuJnID qHJJvOoPNKIu8gzs6wDA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qv17u-008DLm-0B; Mon, 23 Oct 2023 20:02:14 +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 1qv17q-008DKO-1i; Mon, 23 Oct 2023 20:02:12 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding: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=aZyGRwEv0iUdzK429NjcYATM8WFVnBChclCibm7Si3A=; b=pSY/eaDRzPVfujJtREsnNZj+LO /p+NuKMtQPf/2JkoIfPYg79SLzNYeYhtWZOSComP7w9bgywGy/wzZZDFl0NLnmNFNXPESP0sWalS9 VG3DqEOlkmMikGXbr0VhQPXE/lyU5S+xhxhb/vfc+PGsidk3Nk97sdgk+qe1RSt/EC2X16PuOnbZM 0QhdrMpGn9tBUegcvYZl/6LVBSQyqABNIhnYDfZxZuPOLOAAHO85JkzyovjAAkuQkGTVpTiKd0imm TqCx3RsW2GCf1fA/3dfVWzIsA6ghyq96uryRM+fe2equbXYHHK4tYinS3xHwE6EMpwOK1NpiUVdNB mHe3Br5A==; Received: from shell.armlinux.org.uk ([fd8f:7570:feb6:1:5054:ff:fe00:4ec]:56976) by pandora.armlinux.org.uk with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1qv17W-0003Si-0l; Mon, 23 Oct 2023 21:01:50 +0100 Received: from linux by shell.armlinux.org.uk with local (Exim 4.94.2) (envelope-from ) id 1qv17S-0005AN-Pc; Mon, 23 Oct 2023 21:01:46 +0100 Date: Mon, 23 Oct 2023 21:01:46 +0100 From: "Russell King (Oracle)" To: Gavin Shan Cc: Jonathan Cameron , James Morse , 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, Salil Mehta , Jean-Philippe Brucker , jianyong.wu@arm.com, justin.he@arm.com Subject: Re: [RFC PATCH v2 20/35] ACPI: Rename acpi_processor_hotadd_init and remove pre-processor guards Message-ID: References: <20230913163823.7880-1-james.morse@arm.com> <20230913163823.7880-21-james.morse@arm.com> <20230914151720.00007105@Huawei.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20231023_130210_574755_B44E9C26 X-CRM114-Status: GOOD ( 34.57 ) 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: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, Sep 18, 2023 at 03:50:09PM +1000, Gavin Shan wrote: > > On 9/15/23 00:17, Jonathan Cameron wrote: > > On Wed, 13 Sep 2023 16:38:08 +0000 > > James Morse wrote: > > > > > acpi_processor_hotadd_init() will make a CPU present by mapping it > > > based on its hardware id. > > > > > > 'hotadd_init' is ambiguous once there are two different behaviours > > > for cpu hotplug. This is for toggling the _STA present bit. Subsequent > > > patches will add support for toggling the _STA enabled bit, named > > > acpi_processor_make_enabled(). > > > > > > Rename it acpi_processor_make_present() to make it clear this is > > > for CPUs that were not previously present. > > > > > > Expose the function prototypes it uses to allow the preprocessor > > > guards to be removed. The IS_ENABLED() check will let the compiler > > > dead-code elimination pass remove this if it isn't going to be > > > used. > > > > > > Signed-off-by: James Morse > > > --- > > > drivers/acpi/acpi_processor.c | 14 +++++--------- > > > include/linux/acpi.h | 2 -- > > > 2 files changed, 5 insertions(+), 11 deletions(-) > > > > > > diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c > > > index 75257fae10e7..22a15a614f95 100644 > > > --- a/drivers/acpi/acpi_processor.c > > > +++ b/drivers/acpi/acpi_processor.c > > > @@ -182,13 +182,15 @@ static void __init acpi_pcc_cpufreq_init(void) {} > > > #endif /* CONFIG_X86 */ > > > /* Initialization */ > > > -#ifdef CONFIG_ACPI_HOTPLUG_PRESENT_CPU > > > -static int acpi_processor_hotadd_init(struct acpi_processor *pr) > > > +static int acpi_processor_make_present(struct acpi_processor *pr) > > > { > > > unsigned long long sta; > > > acpi_status status; > > > int ret; > > > + if (!IS_ENABLED(CONFIG_ACPI_HOTPLUG_PRESENT_CPU)) > > > + return -ENODEV; > > > + > > > if (invalid_phys_cpuid(pr->phys_id)) > > > return -ENODEV; > > > @@ -222,12 +224,6 @@ static int acpi_processor_hotadd_init(struct acpi_processor *pr) > > > cpu_maps_update_done(); > > > return ret; > > > } > > > -#else > > > -static inline int acpi_processor_hotadd_init(struct acpi_processor *pr) > > > -{ > > > - return -ENODEV; > > > -} > > > -#endif /* CONFIG_ACPI_HOTPLUG_PRESENT_CPU */ > > > static int acpi_processor_get_info(struct acpi_device *device) > > > { > > > @@ -335,7 +331,7 @@ static int acpi_processor_get_info(struct acpi_device *device) > > > * because cpuid <-> apicid mapping is persistent now. > > > */ > > > if (invalid_logical_cpuid(pr->id) || !cpu_present(pr->id)) { > > > - int ret = acpi_processor_hotadd_init(pr); > > > + int ret = acpi_processor_make_present(pr); > > > if (ret) > > > return ret; > > > diff --git a/include/linux/acpi.h b/include/linux/acpi.h > > > index 651dd43976a9..b7ab85857bb7 100644 > > > --- a/include/linux/acpi.h > > > +++ b/include/linux/acpi.h > > > @@ -316,12 +316,10 @@ static inline int acpi_processor_evaluate_cst(acpi_handle handle, u32 cpu, > > > } > > > #endif > > > -#ifdef CONFIG_ACPI_HOTPLUG_PRESENT_CPU > > > /* Arch dependent functions for cpu hotplug support */ > > > int acpi_map_cpu(acpi_handle handle, phys_cpuid_t physid, u32 acpi_id, > > > int *pcpu); > > > int acpi_unmap_cpu(int cpu); > > > > I've lost track somewhat but I think the definitions of these are still under ifdefs > > which is messy if nothing else and might cause build issues. > > > > Yup, it's not safe to use 'if (!IS_ENABLED(CONFIG_ACPI_HOTPLUG_PRESENT_CPU))' in > acpi_processor_make_present() until the ifdefs are removed for those two functions > in individual architectures. The same thing appears in a final patch that James seems to have added to the repository: ACPI: processor: Only call arch_unregister_cpu() if HOTPLUG_CPU is selected in which acpi_processor_post_eject() has this change: - if (!device) + if (!IS_ENABLED(CONFIG_HOTPLUG_CPU) || !device) I'm wondering if that's caused by a previous patch making the weak definition of arch_unregister_cpu() dependent on HOTPLUG_CPU, and whether dropping that ifdef around the function would be better. I think I already asked that question, but this final patch seems to be the confirmation that we need to provide a definition of it. I think the reason James did it like that is because unregister_cpu() is dependent upon CONFIG_HOTPLUG_CPU, but it's probably better to do: #ifdef CONFIG_HOTPLUG_CPU void __weak arch_unregister_cpu(int num) { unregister_cpu(&per_cpu(cpu_devices, num)); } #else void __weak arch_unregister_cpu(int num) { } #endif Agreed? -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last! _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel