From patchwork Fri Dec 20 07:53:10 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yicong Yang X-Patchwork-Id: 13916331 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 B3BF5E77188 for ; Fri, 20 Dec 2024 07:58:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type: Content-Transfer-Encoding:MIME-Version:References:In-Reply-To:Message-ID:Date :Subject:CC:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=FVVZUx/pTRKkwLgQsAmcqsThX8D3c4VM31KgMAtXtvY=; b=eCkC0fS++KaVvwYHiNtcHsB/uE XlCJ9YjS2RC+a/GTnXaXs2vyM4MXVDLfggGQsdlpcu7npGNGUt0/Rk7chBGl0AzvK+U6fG7DhzXYT bxNM25TCdjf5fSFutUwi8iuOnhKzUimigcQdQ+DL0YNBy0lJ1LYObDcWRJJrR9BO7/jn5V1gv4Aet 8IiylCoA7G+C7SiIwLyZlosjTvrOY0IVFtFEHhU1aaOjkPVSm1aaFZeDhpRPx77mPAj8xU98nVTjh nqT2NSM3aJqGS7lIgQ0XDmF7t/C59uU0V0wMRfLNpbJxuuNb7lY90OuM7ASVlqHpXxcNTcFCf+li3 VMRSz32g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tOXtV-00000004DqC-2pjh; Fri, 20 Dec 2024 07:57:57 +0000 Received: from szxga04-in.huawei.com ([45.249.212.190]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tOXq9-00000004D8r-1ibE for linux-arm-kernel@lists.infradead.org; Fri, 20 Dec 2024 07:54:31 +0000 Received: from mail.maildlp.com (unknown [172.19.162.112]) by szxga04-in.huawei.com (SkyGuard) with ESMTP id 4YF03x28jtz2KXph; Fri, 20 Dec 2024 15:51:41 +0800 (CST) Received: from kwepemd200014.china.huawei.com (unknown [7.221.188.8]) by mail.maildlp.com (Postfix) with ESMTPS id 5D986140202; Fri, 20 Dec 2024 15:54:18 +0800 (CST) Received: from localhost.localdomain (10.50.165.33) by kwepemd200014.china.huawei.com (7.221.188.8) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1258.34; Fri, 20 Dec 2024 15:54:17 +0800 From: Yicong Yang To: , , , , , , , , , , , CC: , , , , , , , , , , , , Subject: [PATCH v10 1/4] cpu/SMT: Provide a default topology_is_primary_thread() Date: Fri, 20 Dec 2024 15:53:10 +0800 Message-ID: <20241220075313.51502-2-yangyicong@huawei.com> X-Mailer: git-send-email 2.31.0 In-Reply-To: <20241220075313.51502-1-yangyicong@huawei.com> References: <20241220075313.51502-1-yangyicong@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.50.165.33] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To kwepemd200014.china.huawei.com (7.221.188.8) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241219_235429_769560_51418FDF X-CRM114-Status: GOOD ( 17.18 ) 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: Yicong Yang Currently if architectures want to support HOTPLUG_SMT they need to provide a topology_is_primary_thread() telling the framework which thread in the SMT cannot offline. However arm64 doesn't have a restriction on which thread in the SMT cannot offline, a simplest choice is that just make 1st thread as the "primary" thread. So just make this as the default implementation in the framework and let architectures like x86 that have special primary thread to override this function (which they've already done). There's no need to provide a stub function if !CONFIG_SMP or !CONFIG_HOTPLUG_SMP. In such case the testing CPU is already the 1st CPU in the SMT so it's always the primary thread. Signed-off-by: Yicong Yang Signed-off-by: Yicong Yang --- As questioned in v9 [1] whether this works on architectures not using CONFIG_GENERIC_ARCH_TOPOLOGY, hacked on LoongArch VM and this also works. Architectures should use this on their own situation. [1] https://lore.kernel.org/linux-arm-kernel/427bd639-33c3-47e4-9e83-68c428eb1a7d@arm.com/ [root@localhost smt]# uname -m loongarch64 [root@localhost smt]# pwd /sys/devices/system/cpu/smt [root@localhost smt]# cat ../possible 0-3 [root@localhost smt]# cat ../online 0-3 [root@localhost smt]# cat control on [root@localhost smt]# echo off > control [root@localhost smt]# cat control off [root@localhost smt]# cat ../online 0,2 [root@localhost smt]# echo on > control [root@localhost smt]# cat control on [root@localhost smt]# cat ../online 0-3 arch/powerpc/include/asm/topology.h | 1 + arch/x86/include/asm/topology.h | 2 +- include/linux/topology.h | 22 ++++++++++++++++++++++ 3 files changed, 24 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/include/asm/topology.h b/arch/powerpc/include/asm/topology.h index 16bacfe8c7a2..da15b5efe807 100644 --- a/arch/powerpc/include/asm/topology.h +++ b/arch/powerpc/include/asm/topology.h @@ -152,6 +152,7 @@ static inline bool topology_is_primary_thread(unsigned int cpu) { return cpu == cpu_first_thread_sibling(cpu); } +#define topology_is_primary_thread topology_is_primary_thread static inline bool topology_smt_thread_allowed(unsigned int cpu) { diff --git a/arch/x86/include/asm/topology.h b/arch/x86/include/asm/topology.h index fd41103ad342..faa0d6334ea4 100644 --- a/arch/x86/include/asm/topology.h +++ b/arch/x86/include/asm/topology.h @@ -228,11 +228,11 @@ static inline bool topology_is_primary_thread(unsigned int cpu) { return cpumask_test_cpu(cpu, cpu_primary_thread_mask); } +#define topology_is_primary_thread topology_is_primary_thread #else /* CONFIG_SMP */ static inline int topology_phys_to_logical_pkg(unsigned int pkg) { return 0; } static inline int topology_max_smt_threads(void) { return 1; } -static inline bool topology_is_primary_thread(unsigned int cpu) { return true; } static inline unsigned int topology_amd_nodes_per_pkg(void) { return 1; } #endif /* !CONFIG_SMP */ diff --git a/include/linux/topology.h b/include/linux/topology.h index 52f5850730b3..b3aba443c4eb 100644 --- a/include/linux/topology.h +++ b/include/linux/topology.h @@ -240,6 +240,28 @@ static inline const struct cpumask *cpu_smt_mask(int cpu) } #endif +#ifndef topology_is_primary_thread + +#define topology_is_primary_thread topology_is_primary_thread + +static inline bool topology_is_primary_thread(unsigned int cpu) +{ + /* + * On SMT hotplug the primary thread of the SMT won't be disabled. + * Architectures do have a special primary thread (e.g. x86) need + * to override this function. Otherwise just make the first thread + * in the SMT as the primary thread. + * + * The sibling cpumask of an offline CPU contains always the CPU + * itself for architectures using CONFIG_GENERIC_ARCH_TOPOLOGY. + * Other architectures should use this depend on their own + * situation. + */ + return cpu == cpumask_first(topology_sibling_cpumask(cpu)); +} + +#endif + static inline const struct cpumask *cpu_cpu_mask(int cpu) { return cpumask_of_node(cpu_to_node(cpu)); From patchwork Fri Dec 20 07:53:11 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yicong Yang X-Patchwork-Id: 13916332 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 B9642E77188 for ; Fri, 20 Dec 2024 07:59:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type: Content-Transfer-Encoding:MIME-Version:References:In-Reply-To:Message-ID:Date :Subject:CC:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=noM9PsIoqI0238JO/lKxLrjhK2pdRMsETmp8KFy9dQU=; b=BEVlqPiWZ7ycisQUkp7vBKiDre WT9hbQhpUS4jWPhp38jROLeUf40MaEU2e4q5ePaL8LeH0MlFwva4Om7jhNB652oIOldZFyrIp6PTu lbRlIoCzk5j4QyQjzXYrnkAjYTjt5ZuOwElNCd23mzIs5NG+45Ff+RJ4xfPKTF7yBOYuOQuFih+kV ygLi34y2PWCEm04Npa+rkSo83LY8Y7JKfNtPkpIUQ5RM9wxdymCL7xCL72ZlKX14sDN8yr43HgJ0/ 4iV87+temHc3XKMD1zvwCvAt3naG11sy0QqGHp9d9Io4vkb53/bR4F4rwai68wCZmYyn3vCU/guod 2neZM6Vg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tOXuc-00000004Dwg-1MiP; Fri, 20 Dec 2024 07:59:06 +0000 Received: from szxga05-in.huawei.com ([45.249.212.191]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tOXqA-00000004D8s-01ot for linux-arm-kernel@lists.infradead.org; Fri, 20 Dec 2024 07:54:31 +0000 Received: from mail.maildlp.com (unknown [172.19.163.44]) by szxga05-in.huawei.com (SkyGuard) with ESMTP id 4YF03y1X41z1kwf5; Fri, 20 Dec 2024 15:51:42 +0800 (CST) Received: from kwepemd200014.china.huawei.com (unknown [7.221.188.8]) by mail.maildlp.com (Postfix) with ESMTPS id 1E1AB1402C4; Fri, 20 Dec 2024 15:54:19 +0800 (CST) Received: from localhost.localdomain (10.50.165.33) by kwepemd200014.china.huawei.com (7.221.188.8) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1258.34; Fri, 20 Dec 2024 15:54:18 +0800 From: Yicong Yang To: , , , , , , , , , , , CC: , , , , , , , , , , , , Subject: [PATCH v10 2/4] arch_topology: Support SMT control for OF based system Date: Fri, 20 Dec 2024 15:53:11 +0800 Message-ID: <20241220075313.51502-3-yangyicong@huawei.com> X-Mailer: git-send-email 2.31.0 In-Reply-To: <20241220075313.51502-1-yangyicong@huawei.com> References: <20241220075313.51502-1-yangyicong@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.50.165.33] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To kwepemd200014.china.huawei.com (7.221.188.8) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241219_235430_386973_667028A4 X-CRM114-Status: GOOD ( 16.56 ) 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: Yicong Yang On building the topology from the devicetree, we've already gotten the SMT thread number of each core. Update the largest SMT thread number and enable the SMT control by the end of topology parsing. The core's SMT control provides two interface to the users [1]: 1) enable/disable SMT by writing on/off 2) enable/disable SMT by writing thread number 1/max_thread_number If a system have more than one SMT thread number the 2) may not handle it well, since there're multiple thread numbers in the system and 2) only accept 1/max_thread_number. So issue a warning to notify the users if such system detected. [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/ABI/testing/sysfs-devices-system-cpu#n542 Signed-off-by: Yicong Yang --- drivers/base/arch_topology.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) diff --git a/drivers/base/arch_topology.c b/drivers/base/arch_topology.c index 3ebe77566788..9e81060144c7 100644 --- a/drivers/base/arch_topology.c +++ b/drivers/base/arch_topology.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include #include @@ -506,6 +507,10 @@ core_initcall(free_raw_capacity); #endif #if defined(CONFIG_ARM64) || defined(CONFIG_RISCV) + +/* Maximum SMT thread number detected used to enable the SMT control */ +static unsigned int max_smt_thread_num; + /* * This function returns the logic cpu number of the node. * There are basically three kinds of return values: @@ -565,6 +570,17 @@ static int __init parse_core(struct device_node *core, int package_id, i++; } while (1); + /* + * If max_smt_thread_num has been initialized and doesn't match + * the thread number of this entry, then the system has + * heterogeneous SMT topology. + */ + if (max_smt_thread_num && max_smt_thread_num != i) + pr_warn_once("Heterogeneous SMT topology is partly supported by SMT control\n"); + + if (max_smt_thread_num < i) + max_smt_thread_num = i; + cpu = get_cpu_for_node(core); if (cpu >= 0) { if (!leaf) { @@ -677,6 +693,16 @@ static int __init parse_socket(struct device_node *socket) if (!has_socket) ret = parse_cluster(socket, 0, -1, 0); + /* + * Notify the CPU framework of the SMT support. Initialize the + * max_smt_thread_num to 1 if no SMT support detected. A thread + * number of 1 can be handled by the framework so we don't need + * to check max_smt_thread_num to see we support SMT or not. + */ + if (!max_smt_thread_num) + max_smt_thread_num = 1; + + cpu_smt_set_num_threads(max_smt_thread_num, max_smt_thread_num); return ret; } From patchwork Fri Dec 20 07:53:12 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yicong Yang X-Patchwork-Id: 13916330 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 05EC3E7718A for ; Fri, 20 Dec 2024 07:57:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type: Content-Transfer-Encoding:MIME-Version:References:In-Reply-To:Message-ID:Date :Subject:CC:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=T4LukyvjhjnqKCWrkI0XAWl+mJyXoHQsW4/M2kqs+SU=; b=dg22itUC43efccI43qLq1x4mT+ +JYbbOlZ++pgOry8OZ7L1KOaAPJuv4guu7CyE+iq07Ykp/GwSJ64X68INDGYhLqyISPzJhzNJAcaX GI+HEII9YSVo299nDnrBcHOkb9C860L5Qr/3Q/z75Yr5r3dZilIvXv1+wE11NT4nutGqLPHXhThZC Sd7SBheUSOHqQGUUKsoUpRaG8GbLLotPZpmMOlYwIw3BZBl7cyCeT1syeWdaVTlwXrt+rDAiv4vvX LyQnRqCjROH7QhtFt2G6OUulArqpuwe6nAIhBx/4GZpjIB1lrSqaGIDF4Yu9PyX7zSupEfWihj2Jc oDIvalgA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tOXsO-00000004Dgw-3zEa; Fri, 20 Dec 2024 07:56:48 +0000 Received: from szxga03-in.huawei.com ([45.249.212.189]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tOXq8-00000004D8q-04a0 for linux-arm-kernel@lists.infradead.org; Fri, 20 Dec 2024 07:54:30 +0000 Received: from mail.maildlp.com (unknown [172.19.163.48]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4YF04n1gZJzRjqn; Fri, 20 Dec 2024 15:52:25 +0800 (CST) Received: from kwepemd200014.china.huawei.com (unknown [7.221.188.8]) by mail.maildlp.com (Postfix) with ESMTPS id DA048180064; Fri, 20 Dec 2024 15:54:19 +0800 (CST) Received: from localhost.localdomain (10.50.165.33) by kwepemd200014.china.huawei.com (7.221.188.8) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1258.34; Fri, 20 Dec 2024 15:54:18 +0800 From: Yicong Yang To: , , , , , , , , , , , CC: , , , , , , , , , , , , Subject: [PATCH v10 3/4] arm64: topology: Support SMT control on ACPI based system Date: Fri, 20 Dec 2024 15:53:12 +0800 Message-ID: <20241220075313.51502-4-yangyicong@huawei.com> X-Mailer: git-send-email 2.31.0 In-Reply-To: <20241220075313.51502-1-yangyicong@huawei.com> References: <20241220075313.51502-1-yangyicong@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.50.165.33] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To kwepemd200014.china.huawei.com (7.221.188.8) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241219_235428_383515_8EB192B7 X-CRM114-Status: GOOD ( 22.56 ) 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: Yicong Yang For ACPI we'll build the topology from PPTT and we cannot directly get the SMT number of each core. Instead using a temporary xarray to record the heterogeneous information (from ACPI_PPTT_ACPI_IDENTICAL) and SMT information of the first core in its heterogeneous CPU cluster when building the topology. Then we can know the largest SMT number in the system. If a homogeneous system's using ACPI 6.2 or later, all the CPUs should be under the root node of PPTT. There'll be only one entry in the xarray and all the CPUs in the system will be assumed identical. The core's SMT control provides two interface to the users [1]: 1) enable/disable SMT by writing on/off 2) enable/disable SMT by writing thread number 1/max_thread_number If a system have more than one SMT thread number the 2) may not handle it well, since there're multiple thread numbers in the system and 2) only accept 1/max_thread_number. So issue a warning to notify the users if such system detected. [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/ABI/testing/sysfs-devices-system-cpu#n542 Signed-off-by: Yicong Yang --- arch/arm64/kernel/topology.c | 66 ++++++++++++++++++++++++++++++++++++ 1 file changed, 66 insertions(+) diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c index 1a2c72f3e7f8..85cb18d72a29 100644 --- a/arch/arm64/kernel/topology.c +++ b/arch/arm64/kernel/topology.c @@ -15,8 +15,10 @@ #include #include #include +#include #include #include +#include #include #include @@ -37,17 +39,28 @@ static bool __init acpi_cpu_is_threaded(int cpu) return !!is_threaded; } +struct cpu_smt_info { + int thread_num; + int core_id; +}; + /* * Propagate the topology information of the processor_topology_node tree to the * cpu_topology array. */ int __init parse_acpi_topology(void) { + int max_smt_thread_num = 0; + struct cpu_smt_info *entry; + struct xarray hetero_cpu; + unsigned long hetero_id; int cpu, topology_id; if (acpi_disabled) return 0; + xa_init(&hetero_cpu); + for_each_possible_cpu(cpu) { topology_id = find_acpi_cpu_topology(cpu, 0); if (topology_id < 0) @@ -57,6 +70,32 @@ int __init parse_acpi_topology(void) cpu_topology[cpu].thread_id = topology_id; topology_id = find_acpi_cpu_topology(cpu, 1); cpu_topology[cpu].core_id = topology_id; + + /* + * In the PPTT, CPUs below a node with the 'identical + * implementation' flag have the same number of threads. + * Count the number of threads for only one CPU (i.e. + * one core_id) among those with the same hetero_id. + * See the comment of find_acpi_cpu_topology_hetero_id() + * for more details. + * + * One entry is created for each node having: + * - the 'identical implementation' flag + * - its parent not having the flag + */ + hetero_id = find_acpi_cpu_topology_hetero_id(cpu); + entry = (struct cpu_smt_info *)xa_load(&hetero_cpu, hetero_id); + if (!entry) { + entry = kzalloc(sizeof(*entry), GFP_KERNEL); + WARN_ON(!entry); + + entry->core_id = topology_id; + entry->thread_num = 1; + xa_store(&hetero_cpu, hetero_id, + entry, GFP_KERNEL); + } else if (entry->core_id == topology_id) { + entry->thread_num++; + } } else { cpu_topology[cpu].thread_id = -1; cpu_topology[cpu].core_id = topology_id; @@ -67,6 +106,33 @@ int __init parse_acpi_topology(void) cpu_topology[cpu].package_id = topology_id; } + /* + * This should be a short loop depending on the number of heterogeneous + * CPU clusters. Typically on a homogeneous system there's only one + * entry in the XArray. + */ + xa_for_each(&hetero_cpu, hetero_id, entry) { + if (entry->thread_num != max_smt_thread_num && max_smt_thread_num) + pr_warn_once("Heterogeneous SMT topology is partly supported by SMT control\n"); + + if (entry->thread_num > max_smt_thread_num) + max_smt_thread_num = entry->thread_num; + + xa_erase(&hetero_cpu, hetero_id); + kfree(entry); + } + + /* + * Notify the CPU framework of the SMT support. Initialize the + * max_smt_thread_num to 1 if no SMT support detected. A thread + * number of 1 can be handled by the framework so we don't need + * to check max_smt_thread_num to see we support SMT or not. + */ + if (!max_smt_thread_num) + max_smt_thread_num = 1; + + cpu_smt_set_num_threads(max_smt_thread_num, max_smt_thread_num); + xa_destroy(&hetero_cpu); return 0; } #endif From patchwork Fri Dec 20 07:53:13 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yicong Yang X-Patchwork-Id: 13916333 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 132ADE77188 for ; Fri, 20 Dec 2024 08:00:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type: Content-Transfer-Encoding:MIME-Version:References:In-Reply-To:Message-ID:Date :Subject:CC:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=tUY5QpEDGcLUgE7LGpZZkdx2zTL4wIuHHEobD3RjOLA=; b=wZ7fFXxQD0VxdNDgfNM6qcKqAb ctX85udzbjJ05oU+OZ+LRowIO6AqnfXbYpQxmzBaD/fyxRyrBtO4OIfZ/TRJHE24eF7UxWUZr7rdB HqGJDiNJ0UZfq5IGxj3ZbcXnZkqE2uKXAuhqhyeThYRptYRKIqs++myHTNgN3yiODur3w5MlSebuy fCLGusThP0sEg4WKsBf+UEAbOeLEqIqGrqs7UszDBPn1TQGZdcG98CVjEzpG0OVjBWOcPbyqntInp qMy1q0wSr3Wxv8gtk6dsBSYtoBG9cAlQVhY3G/mCDe8C7BBEIuWo/xhkfXjByltMRPryMC+/iZv/W 1rcOjxcA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tOXvj-00000004E9F-401a; Fri, 20 Dec 2024 08:00:15 +0000 Received: from szxga02-in.huawei.com ([45.249.212.188]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tOXqB-00000004D90-18gq for linux-arm-kernel@lists.infradead.org; Fri, 20 Dec 2024 07:54:32 +0000 Received: from mail.maildlp.com (unknown [172.19.162.254]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4YF04z1LxhzXp80; Fri, 20 Dec 2024 15:52:35 +0800 (CST) Received: from kwepemd200014.china.huawei.com (unknown [7.221.188.8]) by mail.maildlp.com (Postfix) with ESMTPS id A16C4180101; Fri, 20 Dec 2024 15:54:20 +0800 (CST) Received: from localhost.localdomain (10.50.165.33) by kwepemd200014.china.huawei.com (7.221.188.8) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1258.34; Fri, 20 Dec 2024 15:54:19 +0800 From: Yicong Yang To: , , , , , , , , , , , CC: , , , , , , , , , , , , Subject: [PATCH v10 4/4] arm64: Kconfig: Enable HOTPLUG_SMT Date: Fri, 20 Dec 2024 15:53:13 +0800 Message-ID: <20241220075313.51502-5-yangyicong@huawei.com> X-Mailer: git-send-email 2.31.0 In-Reply-To: <20241220075313.51502-1-yangyicong@huawei.com> References: <20241220075313.51502-1-yangyicong@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.50.165.33] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To kwepemd200014.china.huawei.com (7.221.188.8) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241219_235431_485246_903344F6 X-CRM114-Status: UNSURE ( 6.37 ) X-CRM114-Notice: Please train this message. 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: Yicong Yang Enable HOTPLUG_SMT for SMT control. Signed-off-by: Yicong Yang --- arch/arm64/Kconfig | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 100570a048c5..1ee926e2252e 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -246,6 +246,7 @@ config ARM64 select HAVE_KRETPROBES select HAVE_GENERIC_VDSO select HOTPLUG_CORE_SYNC_DEAD if HOTPLUG_CPU + select HOTPLUG_SMT if HOTPLUG_CPU select IRQ_DOMAIN select IRQ_FORCED_THREADING select KASAN_VMALLOC if KASAN