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,URIBL_BLOCKED, 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 7F091C43460 for ; Mon, 17 May 2021 13:44:31 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (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 D7DF660FD8 for ; Mon, 17 May 2021 13:44:30 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D7DF660FD8 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:43480 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lidXq-0006ps-2H for qemu-devel@archiver.kernel.org; Mon, 17 May 2021 09:44:30 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:44808) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lidX5-0005vX-72; Mon, 17 May 2021 09:43:43 -0400 Received: from szxga05-in.huawei.com ([45.249.212.191]:2458) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lidX2-0002Zq-Fj; Mon, 17 May 2021 09:43:42 -0400 Received: from dggems704-chm.china.huawei.com (unknown [172.30.72.60]) by szxga05-in.huawei.com (SkyGuard) with ESMTP id 4FkKxz5BwRzQpFP; Mon, 17 May 2021 21:40:07 +0800 (CST) Received: from dggpemm500023.china.huawei.com (7.185.36.83) by dggems704-chm.china.huawei.com (10.3.19.181) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2176.2; Mon, 17 May 2021 21:43:35 +0800 Received: from [10.174.187.128] (10.174.187.128) by dggpemm500023.china.huawei.com (7.185.36.83) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256) id 15.1.2176.2; Mon, 17 May 2021 21:43:34 +0800 Subject: Re: [RFC PATCH v3 8/9] hw/arm/virt-acpi-build: Generate PPTT table To: Andrew Jones References: <20210516102900.28036-1-wangyanan55@huawei.com> <20210516102900.28036-9-wangyanan55@huawei.com> <20210517080223.sajp445x5qsy57fq@gator.home> From: "wangyanan (Y)" Message-ID: <2dee4bda-fe42-15b1-3a22-22decbc0dbd0@huawei.com> Date: Mon, 17 May 2021 21:43:34 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.4.0 MIME-Version: 1.0 In-Reply-To: <20210517080223.sajp445x5qsy57fq@gator.home> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US X-Originating-IP: [10.174.187.128] X-ClientProxiedBy: dggeme715-chm.china.huawei.com (10.1.199.111) To dggpemm500023.china.huawei.com (7.185.36.83) X-CFilter-Loop: Reflected Received-SPF: pass client-ip=45.249.212.191; envelope-from=wangyanan55@huawei.com; helo=szxga05-in.huawei.com X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, NICE_REPLY_A=-0.001, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Barry Song , Peter Maydell , "Michael S . Tsirkin" , wanghaibin.wang@huawei.com, zhukeqian1@huawei.com, qemu-devel@nongnu.org, yangyicong@huawei.com, Shannon Zhao , qemu-arm@nongnu.org, Alistair Francis , prime.zeng@hisilicon.com, Paolo Bonzini , yuzenghui@huawei.com, Igor Mammedov , =?UTF-8?Q?Philippe_Mathieu-Daud=c3=a9?= , David Gibson Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Hi Drew, On 2021/5/17 16:02, Andrew Jones wrote: > On Sun, May 16, 2021 at 06:28:59PM +0800, Yanan Wang wrote: >> From: Andrew Jones >> >> Add the Processor Properties Topology Table (PPTT) to expose >> CPU topology information defined by users to ACPI guests. >> >> Note, a DT-boot Linux guest with a non-flat CPU topology will >> see socket and core IDs being sequential integers starting >> from zero, which is different from ACPI-boot Linux guest, >> e.g. with -smp 4,sockets=2,cores=2,threads=1 >> >> a DT boot produces: >> >> cpu: 0 package_id: 0 core_id: 0 >> cpu: 1 package_id: 0 core_id: 1 >> cpu: 2 package_id: 1 core_id: 0 >> cpu: 3 package_id: 1 core_id: 1 >> >> an ACPI boot produces: >> >> cpu: 0 package_id: 36 core_id: 0 >> cpu: 1 package_id: 36 core_id: 1 >> cpu: 2 package_id: 96 core_id: 2 >> cpu: 3 package_id: 96 core_id: 3 >> >> This is due to several reasons: >> >> 1) DT cpu nodes do not have an equivalent field to what the PPTT >> ACPI Processor ID must be, i.e. something equal to the MADT CPU >> UID or equal to the UID of an ACPI processor container. In both >> ACPI cases those are platform dependant IDs assigned by the >> vendor. >> >> 2) While QEMU is the vendor for a guest, if the topology specifies >> SMT (> 1 thread), then, with ACPI, it is impossible to assign a >> core-id the same value as a package-id, thus it is not possible >> to have package-id=0 and core-id=0. This is because package and >> core containers must be in the same ACPI namespace and therefore >> must have unique UIDs. >> >> 3) ACPI processor containers are not mandatorily required for PPTT >> tables to be used and, due to the limitations of which IDs are >> selected described above in (2), they are not helpful for QEMU, >> so we don't build them with this patch. In the absence of them, >> Linux assigns its own unique IDs. The maintainers have chosen not >> to use counters from zero, but rather ACPI table offsets, which >> explains why the numbers are so much larger than with DT. >> >> 4) When there is no SMT (threads=1) the core IDs for ACPI boot guests >> match the logical CPU IDs, because these IDs must be equal to the >> MADT CPU UID (as no processor containers are present), and QEMU >> uses the logical CPU ID for these MADT IDs. >> >> So in summary, with QEMU as vender for guest, we use sequential integers >> starting from zero for non-leaf nodes without valid ID flag, so that the >> guest will ignore them and use table offsets as the unique IDs. And we >> also use logical CPU IDs for leaf nodes to be consistent with MADT. >> >> Signed-off-by: Andrew Jones >> Co-developed-by: Yanan Wang >> Signed-off-by: Yanan Wang >> --- >> hw/arm/virt-acpi-build.c | 58 +++++++++++++++++++++++++++++++++++++++- >> 1 file changed, 57 insertions(+), 1 deletion(-) > Why aren't we adding build_pptt to aml-build.c, like my original patch > does? I don't see anything Arm specific below, at least not if you passed > MachineState instead of VirtMachineState, like my original patch did. I agree to move build_pptt to common code, so that other platforms can also use it if they want. I will do it in next version. BTW, it seems patch 1 and 5 were possibly missed for some review. Any comments for them too? Thanks! >> diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c >> index 4d64aeb865..b03d57745a 100644 >> --- a/hw/arm/virt-acpi-build.c >> +++ b/hw/arm/virt-acpi-build.c >> @@ -435,6 +435,57 @@ build_srat(GArray *table_data, BIOSLinker *linker, VirtMachineState *vms) >> vms->oem_table_id); >> } >> >> +/* ACPI 6.2: 5.2.29 Processor Properties Topology Table (PPTT) */ >> +static void build_pptt(GArray *table_data, BIOSLinker *linker, >> + VirtMachineState *vms) >> +{ >> + MachineState *ms = MACHINE(vms); >> + int pptt_start = table_data->len; >> + int uid = 0, socket; >> + >> + acpi_data_push(table_data, sizeof(AcpiTableHeader)); >> + >> + for (socket = 0; socket < ms->smp.sockets; socket++) { >> + uint32_t socket_offset = table_data->len - pptt_start; >> + int core; >> + >> + build_processor_hierarchy_node( >> + table_data, >> + (1 << 0), /* ACPI 6.2 - Physical package */ >> + 0, socket, NULL, 0); >> + >> + for (core = 0; core < ms->smp.cores; core++) { >> + uint32_t core_offset = table_data->len - pptt_start; >> + int thread; >> + >> + if (ms->smp.threads <= 1) { > We can't have threads < 1, so this condition should be == 1. Right, I will fix it. Thanks, Yanan >> + build_processor_hierarchy_node( >> + table_data, >> + (1 << 1) | /* ACPI 6.2 - ACPI Processor ID valid */ >> + (1 << 3), /* ACPI 6.3 - Node is a Leaf */ >> + socket_offset, uid++, NULL, 0); >> + } else { >> + build_processor_hierarchy_node(table_data, 0, socket_offset, >> + core, NULL, 0); >> + >> + for (thread = 0; thread < ms->smp.threads; thread++) { >> + build_processor_hierarchy_node( >> + table_data, >> + (1 << 1) | /* ACPI 6.2 - ACPI Processor ID valid */ >> + (1 << 2) | /* ACPI 6.3 - Processor is a Thread */ >> + (1 << 3), /* ACPI 6.3 - Node is a Leaf */ >> + core_offset, uid++, NULL, 0); >> + } >> + } >> + } >> + } >> + >> + build_header(linker, table_data, >> + (void *)(table_data->data + pptt_start), "PPTT", >> + table_data->len - pptt_start, 2, >> + vms->oem_id, vms->oem_table_id); >> +} >> + >> /* GTDT */ >> static void >> build_gtdt(GArray *table_data, BIOSLinker *linker, VirtMachineState *vms) >> @@ -719,13 +770,18 @@ void virt_acpi_build(VirtMachineState *vms, AcpiBuildTables *tables) >> dsdt = tables_blob->len; >> build_dsdt(tables_blob, tables->linker, vms); >> >> - /* FADT MADT GTDT MCFG SPCR pointed to by RSDT */ >> + /* FADT MADT PPTT GTDT MCFG SPCR pointed to by RSDT */ >> acpi_add_table(table_offsets, tables_blob); >> build_fadt_rev5(tables_blob, tables->linker, vms, dsdt); >> >> acpi_add_table(table_offsets, tables_blob); >> build_madt(tables_blob, tables->linker, vms); >> >> + if (!vmc->no_cpu_topology) { >> + acpi_add_table(table_offsets, tables_blob); >> + build_pptt(tables_blob, tables->linker, vms); >> + } >> + >> acpi_add_table(table_offsets, tables_blob); >> build_gtdt(tables_blob, tables->linker, vms); >> >> -- >> 2.19.1 >> > Thanks, > drew > > .