From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C44F612BF3A; Tue, 16 Apr 2024 14:00:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.176.79.56 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713276013; cv=none; b=eEGzyorkpWFp9lVq/7aGMnmW0kCOboyNd/zycKBQO5T91OUFHC1NzZ+lS4RlS4uXmKf+UPDPrfP/wcSSEqIwWSl42iLqYZZ68j9bH3Fj4Bt0fr8akb1uufrhZTQN6tXdVt8O43gxNJ6PS4K79QY0tAB1csbxldiRcUH3Z998dwA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713276013; c=relaxed/simple; bh=b1c9Idw5WwR1wow0ywz3fwqqsRx0+1L+gWDdhubKeBU=; h=Date:From:To:CC:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=mDTmf4a6nfiGhKVoHnZ8UMaMH6/dvigoOhlEVJx/0MXKd3ifvUJY9qytNv5RP0eD0EzRF2K4zjUtDvKzU48XJPILwqSaZ4nM0h7idcqmTTuU0HTbrmnlZe9HvKdBPjFhMaRX/ZL5lFOUSESFXw2BokpJxca7QcUsGxoC2psBAxM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=Huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=185.176.79.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=Huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.18.186.231]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4VJlsk53Hnz6K8xT; Tue, 16 Apr 2024 21:55:06 +0800 (CST) Received: from lhrpeml500005.china.huawei.com (unknown [7.191.163.240]) by mail.maildlp.com (Postfix) with ESMTPS id DCBEF140B3C; Tue, 16 Apr 2024 22:00:02 +0800 (CST) Received: from localhost (10.202.227.76) by lhrpeml500005.china.huawei.com (7.191.163.240) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.35; Tue, 16 Apr 2024 15:00:02 +0100 Date: Tue, 16 Apr 2024 15:00:01 +0100 From: Jonathan Cameron To: , , , , , , , , Russell King , "Rafael J . Wysocki" , "Miguel Luis" , James Morse , "Salil Mehta" , Jean-Philippe Brucker , Catalin Marinas , "Will Deacon" , CC: , Subject: Re: [PATCH v5 03/18] ACPI: processor: Register deferred CPUs from acpi_processor_get_info() Message-ID: <20240416145917.00004a7b@huawei.com> In-Reply-To: <20240412143719.11398-4-Jonathan.Cameron@huawei.com> References: <20240412143719.11398-1-Jonathan.Cameron@huawei.com> <20240412143719.11398-4-Jonathan.Cameron@huawei.com> Organization: Huawei Technologies Research and Development (UK) Ltd. X-Mailer: Claws Mail 4.1.0 (GTK 3.24.33; x86_64-w64-mingw32) Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-ClientProxiedBy: lhrpeml100006.china.huawei.com (7.191.160.224) To lhrpeml500005.china.huawei.com (7.191.163.240) On Fri, 12 Apr 2024 15:37:04 +0100 Jonathan Cameron wrote: > From: James Morse > > The arm64 specific arch_register_cpu() call may defer CPU registration > until the ACPI interpreter is available and the _STA method can > be evaluated. > > If this occurs, then a second attempt is made in > acpi_processor_get_info(). Note that the arm64 specific call has > not yet been added so for now this will never be successfully > called. > > Systems can still be booted with 'acpi=off', or not include an > ACPI description at all as in these cases arch_register_cpu() > will not have deferred registration when first called. > > This moves the CPU register logic back to a subsys_initcall(), > while the memory nodes will have been registered earlier. > Note this is where the call was prior to the cleanup series so > there should be no side effects of moving it back again for this > specific case. > > [PATCH 00/21] Initial cleanups for vCPU HP. > https://lore.kernel.org/all/ZVyz%2FVe5pPu8AWoA@shell.armlinux.org.uk/ > > e.g. 5b95f94c3b9f ("x86/topology: Switch over to GENERIC_CPU_DEVICES") > > Signed-off-by: James Morse > Reviewed-by: Gavin Shan > Tested-by: Miguel Luis > Tested-by: Vishnu Pajjuri > Tested-by: Jianyong Wu > Signed-off-by: Russell King (Oracle) > Co-developed-by: Jonathan Cameron > Signed-off-by: Joanthan Cameron > --- > v5: Update commit message to make it clear this is moving the > init back to where it was until very recently. > > No longer change the condition in the earlier registration point > as that will be handled by the arm64 registration routine > deferring until called again here. > --- > drivers/acpi/acpi_processor.c | 12 ++++++++++++ > 1 file changed, 12 insertions(+) > > diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c > index 93e029403d05..c78398cdd060 100644 > --- a/drivers/acpi/acpi_processor.c > +++ b/drivers/acpi/acpi_processor.c > @@ -317,6 +317,18 @@ static int acpi_processor_get_info(struct acpi_device *device) > > c = &per_cpu(cpu_devices, pr->id); > ACPI_COMPANION_SET(&c->dev, device); > + /* > + * Register CPUs that are present. get_cpu_device() is used to skip > + * duplicate CPU descriptions from firmware. > + */ > + if (!invalid_logical_cpuid(pr->id) && cpu_present(pr->id) && > + !get_cpu_device(pr->id)) { Just a quick note to call out that this case of 'duplicate' firmware description needs an updated comment. Now we are not deferring registration on x86 this is detecting that arch_register_cpu() has already been successfully called and we should not do it again. I've added rather more detailed comments enumerating of the paths we can take to hit acpi_processor_hotadd_init() in the v6 series (tests ongoing) Jonathan > + int ret = arch_register_cpu(pr->id); > + > + if (ret) > + return ret; > + } > + > /* > * Extra Processor objects may be enumerated on MP systems with > * less than the max # of CPUs. They should be ignored _iff