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 X-Spam-Level: X-Spam-Status: No, score=-15.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8C551C433E0 for ; Mon, 15 Mar 2021 16:16:42 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id A144C64F18 for ; Mon, 15 Mar 2021 16:16:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A144C64F18 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kaod.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4DzhPg5jfCz30Dc for ; Tue, 16 Mar 2021 03:16:39 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=kaod.org (client-ip=178.33.255.19; helo=2.mo51.mail-out.ovh.net; envelope-from=clg@kaod.org; receiver=) Received: from 2.mo51.mail-out.ovh.net (2.mo51.mail-out.ovh.net [178.33.255.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4DzhPJ5Fjbz2yRg for ; Tue, 16 Mar 2021 03:16:18 +1100 (AEDT) Received: from mxplan5.mail.ovh.net (unknown [10.109.156.216]) by mo51.mail-out.ovh.net (Postfix) with ESMTPS id BF667270A7E; Mon, 15 Mar 2021 17:16:15 +0100 (CET) Received: from kaod.org (37.59.142.100) by DAG4EX1.mxp5.local (172.16.2.31) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2106.2; Mon, 15 Mar 2021 17:16:15 +0100 Authentication-Results: garm.ovh; auth=pass (GARM-100R00316cc062d-37cb-4ab2-937a-4f7af29ee175, 6ECECE93D947A1E75FB970C6684F7B2999F5CB5C) smtp.auth=clg@kaod.org X-OVh-ClientIp: 82.64.250.170 Subject: Re: [PATCH] powerpc/numa: Fix topology_physical_package_id() on pSeries To: Daniel Henrique Barboza , References: <20210312143154.3181109-1-clg@kaod.org> From: =?UTF-8?Q?C=c3=a9dric_Le_Goater?= Message-ID: <09b298ce-a566-0542-0aa8-8c4e5248bda6@kaod.org> Date: Mon, 15 Mar 2021 17:16:14 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.6.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 8bit X-Originating-IP: [37.59.142.100] X-ClientProxiedBy: DAG6EX1.mxp5.local (172.16.2.51) To DAG4EX1.mxp5.local (172.16.2.31) X-Ovh-Tracer-GUID: bcaf5aad-f8d8-4a92-9159-987ef8a8c915 X-Ovh-Tracer-Id: 9822069314311916396 X-VR-SPAMSTATE: OK X-VR-SPAMSCORE: -100 X-VR-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrgeduledruddvledgkeeiucetufdoteggodetrfdotffvucfrrhhofhhilhgvmecuqfggjfdpvefjgfevmfevgfenuceurghilhhouhhtmecuhedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmnecujfgurhepuffvfhfhkffffgggjggtgfhisehtkeertddtfeejnecuhfhrohhmpeevrogurhhitggpnfgvpgfiohgrthgvrhcuoegtlhhgsehkrghougdrohhrgheqnecuggftrfgrthhtvghrnhepjeekudeuudevleegudeugeekleffveeludejteffiedvledvgfekueefudehheefnecukfhppedtrddtrddtrddtpdefjedrheelrddugedvrddutddtnecuvehluhhsthgvrhfuihiivgeptdenucfrrghrrghmpehmohguvgepshhmthhpqdhouhhtpdhhvghlohepmhigphhlrghnhedrmhgrihhlrdhovhhhrdhnvghtpdhinhgvtheptddrtddrtddrtddpmhgrihhlfhhrohhmpegtlhhgsehkrghougdrohhrghdprhgtphhtthhopehgrhhouhhgsehkrghougdrohhrgh X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Nathan Lynch , Srikar Dronamraju , Greg Kurz , Vasant Hegde , David Gibson Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On 3/15/21 4:12 PM, Daniel Henrique Barboza wrote: > > > On 3/12/21 11:31 AM, Cédric Le Goater wrote: >> Initial commit 15863ff3b8da ("powerpc: Make chip-id information >> available to userspace") introduce a cpu_to_chip_id() routine for the >> PowerNV platform using the "ibm,chip-id" property to query the chip id >> of a CPU. But PAPR does not specify such a property and the node id >> query is broken. >> >> Use cpu_to_node() instead which guarantees to have a correct value on >> all platforms, PowerNV an pSeries. > > It is worth mentioning that that this patch will change how > topology_physical_package_id() represents in a QEMU guest. Right now, ibm,chip-id > in QEMU is matching the socket-id. After this patch, topology_physical_package_id() > will now match the NUMA id of the CPU. yes. I should have added some more background. LPARs are impacted by the use of ibm,chip-id because the property does not exist under PowerVM and the topology-id in sysfs is always -1 even if NUMA nodes are defined. Under QEMU/KVM, ibm,chip-id is badly calculated when using uncommon SMT configuration. This leads to a bogus topology-id value being exported in sysfs. The use of cpu_to_node() guarantees to have a correct NUMA node id under both environments QEMU/KVM and PowerVM. On the PowerNV platform, the numa node id returned by cpu_to_node() is computed from the "ibm,associativity" property of the CPU. Its value is built from the OPAL chip id and is equivalent to ibm,chip-id. May be I should rephrase the commit log in a v2 ? C. > Reviewed-by: Daniel Henrique Barboza > Tested-by: Daniel Henrique Barboza > >> >> Cc: Nathan Lynch >> Cc: Srikar Dronamraju >> Cc: Vasant Hegde >> Signed-off-by: Cédric Le Goater >> --- >> arch/powerpc/include/asm/topology.h | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/arch/powerpc/include/asm/topology.h b/arch/powerpc/include/asm/topology.h >> index 3beeb030cd78..887c42a4e43d 100644 >> --- a/arch/powerpc/include/asm/topology.h >> +++ b/arch/powerpc/include/asm/topology.h >> @@ -123,7 +123,7 @@ static inline int cpu_to_coregroup_id(int cpu) >> #ifdef CONFIG_PPC64 >> #include >> -#define topology_physical_package_id(cpu) (cpu_to_chip_id(cpu)) >> +#define topology_physical_package_id(cpu) (cpu_to_node(cpu)) >> #define topology_sibling_cpumask(cpu) (per_cpu(cpu_sibling_map, cpu)) >> #define topology_core_cpumask(cpu) (cpu_cpu_mask(cpu)) >>