From patchwork Mon Mar 1 22:59:38 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Song Bao Hua (Barry Song)" X-Patchwork-Id: 12110747 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=-21.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT 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 736E3C433DB for ; Mon, 1 Mar 2021 23:07:42 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 273446023C for ; Mon, 1 Mar 2021 23:07:42 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 273446023C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=hisilicon.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Message-ID:Date: Subject:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=Y7q/50uBElF5myzqKSZcBw6y4iYf1nIaJg/YBL/W6jY=; b=GschJcHlPXWMakAJY0ufUNTk2 ubU6uiHfS1OmmPZ0WwlN+5ZvEJdU7fbNnpzWQknDGE16gh5SKSuPVXJm0Fld8IWP6K3SJXhf8jMPx Ugb1+mrMX2T9ahbjHYfLGlH15EpLeUAX+JdGJskoS7QuKXlAHcdG76nsJdY6oIZxqadzjrRLaDog2 1EOFOcJYGKZEj+QN/+G/wlKV8x9wNxOhZh3YbZiJJvVfhby7IX6XQPHEU1IDK5Pgr1/25WIvz/hJN p+Iu/yoY5qah/gOjX/sHrNts279kTV/9CArXL9sd5hrvdX7ByMOD/0ed4G62a1NS61cj81oS2St1F Y8WVpfZrQ==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1lGrcK-0002U0-LR; Mon, 01 Mar 2021 23:06:20 +0000 Received: from szxga06-in.huawei.com ([45.249.212.32]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1lGrcH-0002Rm-7f for linux-arm-kernel@lists.infradead.org; Mon, 01 Mar 2021 23:06:19 +0000 Received: from DGGEMS412-HUB.china.huawei.com (unknown [172.30.72.59]) by szxga06-in.huawei.com (SkyGuard) with ESMTP id 4DqG7344fLzjSM8; Tue, 2 Mar 2021 07:04:47 +0800 (CST) Received: from SWX921481.china.huawei.com (10.126.203.209) by DGGEMS412-HUB.china.huawei.com (10.3.19.212) with Microsoft SMTP Server id 14.3.498.0; Tue, 2 Mar 2021 07:06:02 +0800 From: Barry Song To: , , , , , , , , , , , , , Subject: [RFC PATCH v4 1/3] topology: Represent clusters of CPUs within a die. Date: Tue, 2 Mar 2021 11:59:38 +1300 Message-ID: <20210301225940.16728-2-song.bao.hua@hisilicon.com> X-Mailer: git-send-email 2.21.0.windows.1 In-Reply-To: <20210301225940.16728-1-song.bao.hua@hisilicon.com> References: <20210301225940.16728-1-song.bao.hua@hisilicon.com> MIME-Version: 1.0 X-Originating-IP: [10.126.203.209] X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210301_180617_757248_3C930755 X-CRM114-Status: GOOD ( 20.60 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: juri.lelli@redhat.com, mark.rutland@arm.com, aubrey.li@linux.intel.com, hpa@zytor.com, prime.zeng@hisilicon.com, guodong.xu@linaro.org, gregkh@linuxfoundation.org, sudeep.holla@arm.com, linux-kernel@vger.kernel.org, linuxarm@openeuler.org, linux-acpi@vger.kernel.org, xuwei5@huawei.com, Jonathan Cameron , yangyicong@huawei.com, x86@kernel.org, msys.mizuma@gmail.com, liguozhu@hisilicon.com, valentin.schneider@arm.com, linux-arm-kernel@lists.infradead.org, Barry Song Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Jonathan Cameron Both ACPI and DT provide the ability to describe additional layers of topology between that of individual cores and higher level constructs such as the level at which the last level cache is shared. In ACPI this can be represented in PPTT as a Processor Hierarchy Node Structure [1] that is the parent of the CPU cores and in turn has a parent Processor Hierarchy Nodes Structure representing a higher level of topology. For example Kunpeng 920 has 6 or 8 clusters in each NUMA node, and each cluster has 4 cpus. All clusters share L3 cache data, but each cluster has local L3 tag. On the other hand, each clusters will share some internal system bus. +-----------------------------------+ +---------+ | +------+ +------+ +---------------------------+ | | | CPU0 | | cpu1 | | +-----------+ | | | +------+ +------+ | | | | | | +----+ L3 | | | | +------+ +------+ cluster | | tag | | | | | CPU2 | | CPU3 | | | | | | | +------+ +------+ | +-----------+ | | | | | | +-----------------------------------+ | | +-----------------------------------+ | | | +------+ +------+ +--------------------------+ | | | | | | | +-----------+ | | | +------+ +------+ | | | | | | | | L3 | | | | +------+ +------+ +----+ tag | | | | | | | | | | | | | | +------+ +------+ | +-----------+ | | | | | | +-----------------------------------+ | L3 | | data | +-----------------------------------+ | | | +------+ +------+ | +-----------+ | | | | | | | | | | | | | +------+ +------+ +----+ L3 | | | | | | tag | | | | +------+ +------+ | | | | | | | | | | ++ +-----------+ | | | +------+ +------+ |---------------------------+ | +-----------------------------------| | | +-----------------------------------| | | | +------+ +------+ +---------------------------+ | | | | | | | +-----------+ | | | +------+ +------+ | | | | | | +----+ L3 | | | | +------+ +------+ | | tag | | | | | | | | | | | | | | +------+ +------+ | +-----------+ | | | | | | +-----------------------------------+ | | +-----------------------------------+ | | | +------+ +------+ +--------------------------+ | | | | | | | +-----------+ | | | +------+ +------+ | | | | | | | | L3 | | | | +------+ +------+ +---+ tag | | | | | | | | | | | | | | +------+ +------+ | +-----------+ | | | | | | +-----------------------------------+ | | +-----------------------------------+ ++ | | +------+ +------+ +--------------------------+ | | | | | | | +-----------+ | | | +------+ +------+ | | | | | | | | L3 | | | | +------+ +------+ +--+ tag | | | | | | | | | | | | | | +------+ +------+ | +-----------+ | | | | +---------+ +-----------------------------------+ That means the cost to transfer ownership of a cacheline between CPUs within a cluster is lower than between CPUs in different clusters on the same die. Hence, it can make sense to tell the scheduler to use the cache affinity of the cluster to make better decision on thread migration. This patch simply exposes this information to userspace libraries like hwloc by providing cluster_cpus and related sysfs attributes. PoC of HWLOC support at [2]. Note this patch only handle the ACPI case. Special consideration is needed for SMT processors, where it is necessary to move 2 levels up the hierarchy from the leaf nodes (thus skipping the processor core level). Currently the ID provided is the offset of the Processor Hierarchy Nodes Structure within PPTT. Whilst this is unique it is not terribly elegant so alternative suggestions welcome. Note that arm64 / ACPI does not provide any means of identifying a die level in the topology but that may be unrelate to the cluster level. [1] ACPI Specification 6.3 - section 5.2.29.1 processor hierarchy node structure (Type 0) [2] https://github.com/hisilicon/hwloc/tree/linux-cluster Signed-off-by: Jonathan Cameron Signed-off-by: Barry Song --- -v4: * used acpi_cpu_id for acpi_find_processor_node(addressing Masa's comment) Documentation/admin-guide/cputopology.rst | 26 +++++++++++-- arch/arm64/kernel/topology.c | 2 + drivers/acpi/pptt.c | 63 +++++++++++++++++++++++++++++++ drivers/base/arch_topology.c | 14 +++++++ drivers/base/topology.c | 10 +++++ include/linux/acpi.h | 5 +++ include/linux/arch_topology.h | 5 +++ include/linux/topology.h | 6 +++ 8 files changed, 127 insertions(+), 4 deletions(-) diff --git a/Documentation/admin-guide/cputopology.rst b/Documentation/admin-guide/cputopology.rst index b90dafc..f9d3745 100644 --- a/Documentation/admin-guide/cputopology.rst +++ b/Documentation/admin-guide/cputopology.rst @@ -24,6 +24,12 @@ core_id: identifier (rather than the kernel's). The actual value is architecture and platform dependent. +cluster_id: + + the Cluster ID of cpuX. Typically it is the hardware platform's + identifier (rather than the kernel's). The actual value is + architecture and platform dependent. + book_id: the book ID of cpuX. Typically it is the hardware platform's @@ -56,6 +62,14 @@ package_cpus_list: human-readable list of CPUs sharing the same physical_package_id. (deprecated name: "core_siblings_list") +cluster_cpus: + + internal kernel map of CPUs within the same cluster. + +cluster_cpus_list: + + human-readable list of CPUs within the same cluster. + die_cpus: internal kernel map of CPUs within the same die. @@ -96,11 +110,13 @@ these macros in include/asm-XXX/topology.h:: #define topology_physical_package_id(cpu) #define topology_die_id(cpu) + #define topology_cluster_id(cpu) #define topology_core_id(cpu) #define topology_book_id(cpu) #define topology_drawer_id(cpu) #define topology_sibling_cpumask(cpu) #define topology_core_cpumask(cpu) + #define topology_cluster_cpumask(cpu) #define topology_die_cpumask(cpu) #define topology_book_cpumask(cpu) #define topology_drawer_cpumask(cpu) @@ -116,10 +132,12 @@ not defined by include/asm-XXX/topology.h: 1) topology_physical_package_id: -1 2) topology_die_id: -1 -3) topology_core_id: 0 -4) topology_sibling_cpumask: just the given CPU -5) topology_core_cpumask: just the given CPU -6) topology_die_cpumask: just the given CPU +3) topology_cluster_id: -1 +4) topology_core_id: 0 +5) topology_sibling_cpumask: just the given CPU +6) topology_core_cpumask: just the given CPU +7) topology_cluster_cpumask: just the given CPU +8) topology_die_cpumask: just the given CPU For architectures that don't support books (CONFIG_SCHED_BOOK) there are no default definitions for topology_book_id() and topology_book_cpumask(). diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c index f6faa69..fe076b3 100644 --- a/arch/arm64/kernel/topology.c +++ b/arch/arm64/kernel/topology.c @@ -103,6 +103,8 @@ int __init parse_acpi_topology(void) cpu_topology[cpu].thread_id = -1; cpu_topology[cpu].core_id = topology_id; } + topology_id = find_acpi_cpu_topology_cluster(cpu); + cpu_topology[cpu].cluster_id = topology_id; topology_id = find_acpi_cpu_topology_package(cpu); cpu_topology[cpu].package_id = topology_id; diff --git a/drivers/acpi/pptt.c b/drivers/acpi/pptt.c index 4ae9335..11f8b02 100644 --- a/drivers/acpi/pptt.c +++ b/drivers/acpi/pptt.c @@ -737,6 +737,69 @@ int find_acpi_cpu_topology_package(unsigned int cpu) } /** + * find_acpi_cpu_topology_cluster() - Determine a unique CPU cluster value + * @cpu: Kernel logical CPU number + * + * Determine a topology unique cluster ID for the given CPU/thread. + * This ID can then be used to group peers, which will have matching ids. + * + * The cluster, if present is the level of topology above CPUs. In a + * multi-thread CPU, it will be the level above the CPU, not the thread. + * It may not exist in single CPU systems. In simple multi-CPU systems, + * it may be equal to the package topology level. + * + * Return: -ENOENT if the PPTT doesn't exist, the CPU cannot be found + * or there is no toplogy level above the CPU.. + * Otherwise returns a value which represents the package for this CPU. + */ + +int find_acpi_cpu_topology_cluster(unsigned int cpu) +{ + struct acpi_table_header *table; + acpi_status status; + struct acpi_pptt_processor *cpu_node, *cluster_node; + u32 acpi_cpu_id; + int retval; + int is_thread; + + status = acpi_get_table(ACPI_SIG_PPTT, 0, &table); + if (ACPI_FAILURE(status)) { + acpi_pptt_warn_missing(); + return -ENOENT; + } + + acpi_cpu_id = get_acpi_id_for_cpu(cpu); + cpu_node = acpi_find_processor_node(table, acpi_cpu_id); + if (cpu_node == NULL || !cpu_node->parent) { + retval = -ENOENT; + goto put_table; + } + + is_thread = cpu_node->flags & ACPI_PPTT_ACPI_PROCESSOR_IS_THREAD; + cluster_node = fetch_pptt_node(table, cpu_node->parent); + if (cluster_node == NULL) { + retval = -ENOENT; + goto put_table; + } + if (is_thread) { + if (!cluster_node->parent) { + retval = -ENOENT; + goto put_table; + } + cluster_node = fetch_pptt_node(table, cluster_node->parent); + if (cluster_node == NULL) { + retval = -ENOENT; + goto put_table; + } + } + retval = ACPI_PTR_DIFF(cluster_node, table); +put_table: + acpi_put_table(table); + + return retval; +} + +/** * find_acpi_cpu_topology_hetero_id() - Get a core architecture tag * @cpu: Kernel logical CPU number * diff --git a/drivers/base/arch_topology.c b/drivers/base/arch_topology.c index de8587c..3079232 100644 --- a/drivers/base/arch_topology.c +++ b/drivers/base/arch_topology.c @@ -506,6 +506,11 @@ const struct cpumask *cpu_coregroup_mask(int cpu) return core_mask; } +const struct cpumask *cpu_clustergroup_mask(int cpu) +{ + return &cpu_topology[cpu].cluster_sibling; +} + void update_siblings_masks(unsigned int cpuid) { struct cpu_topology *cpu_topo, *cpuid_topo = &cpu_topology[cpuid]; @@ -523,6 +528,11 @@ void update_siblings_masks(unsigned int cpuid) if (cpuid_topo->package_id != cpu_topo->package_id) continue; + if (cpuid_topo->cluster_id == cpu_topo->cluster_id) { + cpumask_set_cpu(cpu, &cpuid_topo->cluster_sibling); + cpumask_set_cpu(cpuid, &cpu_topo->cluster_sibling); + } + cpumask_set_cpu(cpuid, &cpu_topo->core_sibling); cpumask_set_cpu(cpu, &cpuid_topo->core_sibling); @@ -541,6 +551,9 @@ static void clear_cpu_topology(int cpu) cpumask_clear(&cpu_topo->llc_sibling); cpumask_set_cpu(cpu, &cpu_topo->llc_sibling); + cpumask_clear(&cpu_topo->cluster_sibling); + cpumask_set_cpu(cpu, &cpu_topo->cluster_sibling); + cpumask_clear(&cpu_topo->core_sibling); cpumask_set_cpu(cpu, &cpu_topo->core_sibling); cpumask_clear(&cpu_topo->thread_sibling); @@ -571,6 +584,7 @@ void remove_cpu_topology(unsigned int cpu) cpumask_clear_cpu(cpu, topology_core_cpumask(sibling)); for_each_cpu(sibling, topology_sibling_cpumask(cpu)) cpumask_clear_cpu(cpu, topology_sibling_cpumask(sibling)); + for_each_cpu(sibling, topology_llc_cpumask(cpu)) cpumask_clear_cpu(cpu, topology_llc_cpumask(sibling)); diff --git a/drivers/base/topology.c b/drivers/base/topology.c index 4d254fc..7157ac0 100644 --- a/drivers/base/topology.c +++ b/drivers/base/topology.c @@ -46,6 +46,9 @@ define_id_show_func(die_id); static DEVICE_ATTR_RO(die_id); +define_id_show_func(cluster_id); +static DEVICE_ATTR_RO(cluster_id); + define_id_show_func(core_id); static DEVICE_ATTR_RO(core_id); @@ -61,6 +64,10 @@ static DEVICE_ATTR_RO(core_siblings); static DEVICE_ATTR_RO(core_siblings_list); +define_siblings_show_func(cluster_cpus, cluster_cpumask); +static DEVICE_ATTR_RO(cluster_cpus); +static DEVICE_ATTR_RO(cluster_cpus_list); + define_siblings_show_func(die_cpus, die_cpumask); static DEVICE_ATTR_RO(die_cpus); static DEVICE_ATTR_RO(die_cpus_list); @@ -88,6 +95,7 @@ static struct attribute *default_attrs[] = { &dev_attr_physical_package_id.attr, &dev_attr_die_id.attr, + &dev_attr_cluster_id.attr, &dev_attr_core_id.attr, &dev_attr_thread_siblings.attr, &dev_attr_thread_siblings_list.attr, @@ -95,6 +103,8 @@ &dev_attr_core_cpus_list.attr, &dev_attr_core_siblings.attr, &dev_attr_core_siblings_list.attr, + &dev_attr_cluster_cpus.attr, + &dev_attr_cluster_cpus_list.attr, &dev_attr_die_cpus.attr, &dev_attr_die_cpus_list.attr, &dev_attr_package_cpus.attr, diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 053bf05..161196a 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -1332,6 +1332,7 @@ static inline int lpit_read_residency_count_address(u64 *address) #ifdef CONFIG_ACPI_PPTT int acpi_pptt_cpu_is_thread(unsigned int cpu); int find_acpi_cpu_topology(unsigned int cpu, int level); +int find_acpi_cpu_topology_cluster(unsigned int cpu); int find_acpi_cpu_topology_package(unsigned int cpu); int find_acpi_cpu_topology_hetero_id(unsigned int cpu); int find_acpi_cpu_cache_topology(unsigned int cpu, int level); @@ -1344,6 +1345,10 @@ static inline int find_acpi_cpu_topology(unsigned int cpu, int level) { return -EINVAL; } +static inline int find_acpi_cpu_topology_cluster(unsigned int cpu) +{ + return -EINVAL; +} static inline int find_acpi_cpu_topology_package(unsigned int cpu) { return -EINVAL; diff --git a/include/linux/arch_topology.h b/include/linux/arch_topology.h index 0f6cd6b..987c7ea 100644 --- a/include/linux/arch_topology.h +++ b/include/linux/arch_topology.h @@ -49,10 +49,12 @@ void topology_set_thermal_pressure(const struct cpumask *cpus, struct cpu_topology { int thread_id; int core_id; + int cluster_id; int package_id; int llc_id; cpumask_t thread_sibling; cpumask_t core_sibling; + cpumask_t cluster_sibling; cpumask_t llc_sibling; }; @@ -60,13 +62,16 @@ struct cpu_topology { extern struct cpu_topology cpu_topology[NR_CPUS]; #define topology_physical_package_id(cpu) (cpu_topology[cpu].package_id) +#define topology_cluster_id(cpu) (cpu_topology[cpu].cluster_id) #define topology_core_id(cpu) (cpu_topology[cpu].core_id) #define topology_core_cpumask(cpu) (&cpu_topology[cpu].core_sibling) #define topology_sibling_cpumask(cpu) (&cpu_topology[cpu].thread_sibling) +#define topology_cluster_cpumask(cpu) (&cpu_topology[cpu].cluster_sibling) #define topology_llc_cpumask(cpu) (&cpu_topology[cpu].llc_sibling) void init_cpu_topology(void); void store_cpu_topology(unsigned int cpuid); const struct cpumask *cpu_coregroup_mask(int cpu); +const struct cpumask *cpu_clustergroup_mask(int cpu); void update_siblings_masks(unsigned int cpu); void remove_cpu_topology(unsigned int cpuid); void reset_cpu_topology(void); diff --git a/include/linux/topology.h b/include/linux/topology.h index 7634cd7..80d27d7 100644 --- a/include/linux/topology.h +++ b/include/linux/topology.h @@ -186,6 +186,9 @@ static inline int cpu_to_mem(int cpu) #ifndef topology_die_id #define topology_die_id(cpu) ((void)(cpu), -1) #endif +#ifndef topology_cluster_id +#define topology_cluster_id(cpu) ((void)(cpu), -1) +#endif #ifndef topology_core_id #define topology_core_id(cpu) ((void)(cpu), 0) #endif @@ -195,6 +198,9 @@ static inline int cpu_to_mem(int cpu) #ifndef topology_core_cpumask #define topology_core_cpumask(cpu) cpumask_of(cpu) #endif +#ifndef topology_cluster_cpumask +#define topology_cluster_cpumask(cpu) cpumask_of(cpu) +#endif #ifndef topology_die_cpumask #define topology_die_cpumask(cpu) cpumask_of(cpu) #endif From patchwork Mon Mar 1 22:59:39 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Song Bao Hua (Barry Song)" X-Patchwork-Id: 12110749 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=-16.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 8AB44C433E6 for ; Mon, 1 Mar 2021 23:07:43 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 488E160231 for ; Mon, 1 Mar 2021 23:07:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 488E160231 Authentication-Results: mail.kernel.org; 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Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1lGrcO-0002VC-RZ; Mon, 01 Mar 2021 23:06:24 +0000 Received: from szxga05-in.huawei.com ([45.249.212.191]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1lGrcL-0002Tw-Bo for linux-arm-kernel@lists.infradead.org; Mon, 01 Mar 2021 23:06:23 +0000 Received: from DGGEMS412-HUB.china.huawei.com (unknown [172.30.72.59]) by szxga05-in.huawei.com (SkyGuard) with ESMTP id 4DqG6t6yGKzjTnJ; Tue, 2 Mar 2021 07:04:38 +0800 (CST) Received: from SWX921481.china.huawei.com (10.126.203.209) by DGGEMS412-HUB.china.huawei.com (10.3.19.212) with Microsoft SMTP Server id 14.3.498.0; Tue, 2 Mar 2021 07:06:09 +0800 From: Barry Song To: , , , , , , , , , , , , , Subject: [RFC PATCH v4 2/3] scheduler: add scheduler level for clusters Date: Tue, 2 Mar 2021 11:59:39 +1300 Message-ID: <20210301225940.16728-3-song.bao.hua@hisilicon.com> X-Mailer: git-send-email 2.21.0.windows.1 In-Reply-To: <20210301225940.16728-1-song.bao.hua@hisilicon.com> References: <20210301225940.16728-1-song.bao.hua@hisilicon.com> MIME-Version: 1.0 X-Originating-IP: [10.126.203.209] X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210301_180621_910493_51DDE96C X-CRM114-Status: GOOD ( 26.56 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: juri.lelli@redhat.com, mark.rutland@arm.com, aubrey.li@linux.intel.com, hpa@zytor.com, prime.zeng@hisilicon.com, guodong.xu@linaro.org, gregkh@linuxfoundation.org, sudeep.holla@arm.com, linux-kernel@vger.kernel.org, linuxarm@openeuler.org, linux-acpi@vger.kernel.org, xuwei5@huawei.com, jonathan.cameron@huawei.com, yangyicong@huawei.com, x86@kernel.org, msys.mizuma@gmail.com, liguozhu@hisilicon.com, valentin.schneider@arm.com, linux-arm-kernel@lists.infradead.org, Barry Song Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org ARM64 chip Kunpeng 920 has 6 or 8 clusters in each NUMA node, and each cluster has 4 cpus. All clusters share L3 cache data, but each cluster has local L3 tag. On the other hand, each clusters will share some internal system bus. This means cache coherence overhead inside one cluster is much less than the overhead across clusters. This patch adds the sched_domain for clusters. On kunpeng 920, without this patch, domain0 of cpu0 would be MC with cpu0~cpu23 with ; with this patch, MC becomes domain1, a new domain0 "CLS" including cpu0-cpu3. This will help spread unrelated tasks among clusters, thus decrease the contention and improve the throughput, for example, stream benchmark can improve around 4.3%~6.3% by this patch: w/o patch: numactl -N 0 /usr/lib/lmbench/bin/stream -P 12 -M 1024M -N 5 STREAM copy latency: 3.36 nanoseconds STREAM copy bandwidth: 57072.50 MB/sec STREAM scale latency: 3.40 nanoseconds STREAM scale bandwidth: 56542.52 MB/sec STREAM add latency: 5.10 nanoseconds STREAM add bandwidth: 56482.83 MB/sec STREAM triad latency: 5.14 nanoseconds STREAM triad bandwidth: 56069.52 MB/sec w/ patch: $ numactl -N 0 /usr/lib/lmbench/bin/stream -P 12 -M 1024M -N 5 STREAM copy latency: 3.22 nanoseconds STREAM copy bandwidth: 59660.96 MB/sec -> +4.5% STREAM scale latency: 3.25 nanoseconds STREAM scale bandwidth: 59002.29 MB/sec -> +4.3% STREAM add latency: 4.80 nanoseconds STREAM add bandwidth: 60036.62 MB/sec -> +6.3% STREAM triad latency: 4.86 nanoseconds STREAM triad bandwidth: 59228.30 MB/sec -> +5.6% On the other hand, while doing WAKE_AFFINE, this patch will try to find a core in the target cluster before scanning the whole llc domain. So it helps gather related tasks within one cluster. we run the below hackbench with different -g parameter from 2 to 14, for each different g, we run the command 10 times and get the average time $ numactl -N 0 hackbench -p -T -l 20000 -g $1 hackbench will report the time which is needed to complete a certain number of messages transmissions between a certain number of tasks, for example: $ numactl -N 0 hackbench -p -T -l 20000 -g 10 Running in threaded mode with 10 groups using 40 file descriptors each (== 400 tasks) Each sender will pass 20000 messages of 100 bytes Time: 8.874 The below is the result of hackbench w/ and w/o the patch: g= 2 4 6 8 10 12 14 w/o: 1.9596 4.0506 5.9654 8.0068 9.8147 11.4900 13.1163 w/ : 1.9362 3.9197 5.6570 7.1376 8.5263 10.0512 11.3256 +3.3% +5.2% +10.9% +13.2% +12.8% +13.7% Signed-off-by: Barry Song --- -v4: * rebased to tip/sched/core with the latest unified code of select_idle_cpu * also added benchmark data of spreading unrelated tasks * avoided the iteration of sched_domain by moving to static_key(addressing Vincent's comment arch/arm64/Kconfig | 7 +++++ include/linux/sched/cluster.h | 19 ++++++++++++ include/linux/sched/sd_flags.h | 9 ++++++ include/linux/sched/topology.h | 7 +++++ include/linux/topology.h | 7 +++++ kernel/sched/core.c | 18 ++++++++++++ kernel/sched/fair.c | 66 +++++++++++++++++++++++++++++++++--------- kernel/sched/sched.h | 1 + kernel/sched/topology.c | 6 ++++ 9 files changed, 126 insertions(+), 14 deletions(-) create mode 100644 include/linux/sched/cluster.h diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index f39568b..158b0fa 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -971,6 +971,13 @@ config SCHED_MC making when dealing with multi-core CPU chips at a cost of slightly increased overhead in some places. If unsure say N here. +config SCHED_CLUSTER + bool "Cluster scheduler support" + help + Cluster scheduler support improves the CPU scheduler's decision + making when dealing with machines that have clusters(sharing internal + bus or sharing LLC cache tag). If unsure say N here. + config SCHED_SMT bool "SMT scheduler support" help diff --git a/include/linux/sched/cluster.h b/include/linux/sched/cluster.h new file mode 100644 index 0000000..ea6c475 --- /dev/null +++ b/include/linux/sched/cluster.h @@ -0,0 +1,19 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _LINUX_SCHED_CLUSTER_H +#define _LINUX_SCHED_CLUSTER_H + +#include + +#ifdef CONFIG_SCHED_CLUSTER +extern struct static_key_false sched_cluster_present; + +static __always_inline bool sched_cluster_active(void) +{ + return static_branch_likely(&sched_cluster_present); +} +#else +static inline bool sched_cluster_active(void) { return false; } + +#endif + +#endif diff --git a/include/linux/sched/sd_flags.h b/include/linux/sched/sd_flags.h index 34b21e9..fc3c894 100644 --- a/include/linux/sched/sd_flags.h +++ b/include/linux/sched/sd_flags.h @@ -100,6 +100,15 @@ SD_FLAG(SD_SHARE_CPUCAPACITY, SDF_SHARED_CHILD | SDF_NEEDS_GROUPS) /* + * Domain members share CPU cluster resources (i.e. llc cache tags) + * + * SHARED_CHILD: Set from the base domain up until spanned CPUs no longer share + * the cluster resouces (such as llc tags and internal bus) + * NEEDS_GROUPS: Caches are shared between groups. + */ +SD_FLAG(SD_SHARE_CLS_RESOURCES, SDF_SHARED_CHILD | SDF_NEEDS_GROUPS) + +/* * Domain members share CPU package resources (i.e. caches) * * SHARED_CHILD: Set from the base domain up until spanned CPUs no longer share diff --git a/include/linux/sched/topology.h b/include/linux/sched/topology.h index 8f0f778..846fcac 100644 --- a/include/linux/sched/topology.h +++ b/include/linux/sched/topology.h @@ -42,6 +42,13 @@ static inline int cpu_smt_flags(void) } #endif +#ifdef CONFIG_SCHED_CLUSTER +static inline int cpu_cluster_flags(void) +{ + return SD_SHARE_CLS_RESOURCES | SD_SHARE_PKG_RESOURCES; +} +#endif + #ifdef CONFIG_SCHED_MC static inline int cpu_core_flags(void) { diff --git a/include/linux/topology.h b/include/linux/topology.h index 80d27d7..0b3704a 100644 --- a/include/linux/topology.h +++ b/include/linux/topology.h @@ -212,6 +212,13 @@ static inline const struct cpumask *cpu_smt_mask(int cpu) } #endif +#if defined(CONFIG_SCHED_CLUSTER) && !defined(cpu_cluster_mask) +static inline const struct cpumask *cpu_cluster_mask(int cpu) +{ + return topology_cluster_cpumask(cpu); +} +#endif + static inline const struct cpumask *cpu_cpu_mask(int cpu) { return cpumask_of_node(cpu_to_node(cpu)); diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 88a2e2b..d805e59 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -7797,6 +7797,16 @@ int sched_cpu_activate(unsigned int cpu) if (cpumask_weight(cpu_smt_mask(cpu)) == 2) static_branch_inc_cpuslocked(&sched_smt_present); #endif + +#ifdef CONFIG_SCHED_CLUSTER + /* + * When going up, increment the number of cluster cpus with + * cluster present. + */ + if (cpumask_weight(cpu_cluster_mask(cpu)) > 1) + static_branch_inc_cpuslocked(&sched_cluster_present); +#endif + set_cpu_active(cpu, true); if (sched_smp_initialized) { @@ -7873,6 +7883,14 @@ int sched_cpu_deactivate(unsigned int cpu) static_branch_dec_cpuslocked(&sched_smt_present); #endif +#ifdef CONFIG_SCHED_CLUSTER + /* + * When going down, decrement the number of cpus with cluster present. + */ + if (cpumask_weight(cpu_cluster_mask(cpu)) > 1) + static_branch_dec_cpuslocked(&sched_cluster_present); +#endif + if (!sched_smp_initialized) return 0; diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 8a8bd7b..3db7b07 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -6009,6 +6009,11 @@ static inline int __select_idle_cpu(int cpu) return -1; } +#ifdef CONFIG_SCHED_CLUSTER +DEFINE_STATIC_KEY_FALSE(sched_cluster_present); +EXPORT_SYMBOL_GPL(sched_cluster_present); +#endif + #ifdef CONFIG_SCHED_SMT DEFINE_STATIC_KEY_FALSE(sched_smt_present); EXPORT_SYMBOL_GPL(sched_smt_present); @@ -6116,6 +6121,26 @@ static inline int select_idle_core(struct task_struct *p, int core, struct cpuma #endif /* CONFIG_SCHED_SMT */ +static inline int _select_idle_cpu(bool smt, struct task_struct *p, int target, struct cpumask *cpus, int *idle_cpu, int *nr) +{ + int cpu, i; + + for_each_cpu_wrap(cpu, cpus, target) { + if (smt) { + i = select_idle_core(p, cpu, cpus, idle_cpu); + } else { + if (!--*nr) + return -1; + i = __select_idle_cpu(cpu); + } + + if ((unsigned int)i < nr_cpumask_bits) + return i; + } + + return -1; +} + /* * Scan the LLC domain for idle CPUs; this is dynamically regulated by * comparing the average scan cost (tracked in sd->avg_scan_cost) against the @@ -6124,7 +6149,7 @@ static inline int select_idle_core(struct task_struct *p, int core, struct cpuma static int select_idle_cpu(struct task_struct *p, struct sched_domain *sd, int target) { struct cpumask *cpus = this_cpu_cpumask_var_ptr(select_idle_mask); - int i, cpu, idle_cpu = -1, nr = INT_MAX; + int i, idle_cpu = -1, nr = INT_MAX; bool smt = test_idle_cores(target, false); int this = smp_processor_id(); struct sched_domain *this_sd; @@ -6134,7 +6159,12 @@ static int select_idle_cpu(struct task_struct *p, struct sched_domain *sd, int t if (!this_sd) return -1; - cpumask_and(cpus, sched_domain_span(sd), p->cpus_ptr); + if (!sched_cluster_active()) + cpumask_and(cpus, sched_domain_span(sd), p->cpus_ptr); +#ifdef CONFIG_SCHED_CLUSTER + if (sched_cluster_active()) + cpumask_and(cpus, cpu_cluster_mask(target), p->cpus_ptr); +#endif if (sched_feat(SIS_PROP) && !smt) { u64 avg_cost, avg_idle, span_avg; @@ -6155,24 +6185,32 @@ static int select_idle_cpu(struct task_struct *p, struct sched_domain *sd, int t time = cpu_clock(this); } - for_each_cpu_wrap(cpu, cpus, target) { - if (smt) { - i = select_idle_core(p, cpu, cpus, &idle_cpu); - if ((unsigned int)i < nr_cpumask_bits) - return i; + /* scan cluster before scanning the whole llc */ +#ifdef CONFIG_SCHED_CLUSTER + if (sched_cluster_active()) { + i = _select_idle_cpu(smt, p, target, cpus, &idle_cpu, &nr); + if ((unsigned int) i < nr_cpumask_bits) { + idle_cpu = i; + goto done; + } else if (nr <= 0) + return -1; - } else { - if (!--nr) - return -1; - idle_cpu = __select_idle_cpu(cpu); - if ((unsigned int)idle_cpu < nr_cpumask_bits) - break; - } + cpumask_and(cpus, sched_domain_span(sd), p->cpus_ptr); + cpumask_andnot(cpus, cpus, cpu_cluster_mask(target)); } +#endif + + i = _select_idle_cpu(smt, p, target, cpus, &idle_cpu, &nr); + if ((unsigned int) i < nr_cpumask_bits) { + idle_cpu = i; + goto done; + } else if (nr <= 0) + return -1; if (smt) set_idle_cores(this, false); +done: if (sched_feat(SIS_PROP) && !smt) { time = cpu_clock(this) - time; update_avg(&this_sd->avg_scan_cost, time); diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 10a1522..48a020f 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -6,6 +6,7 @@ #include #include +#include #include #include #include diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c index 09d3504..d019c25 100644 --- a/kernel/sched/topology.c +++ b/kernel/sched/topology.c @@ -1361,6 +1361,7 @@ static void claim_allocations(int cpu, struct sched_domain *sd) */ #define TOPOLOGY_SD_FLAGS \ (SD_SHARE_CPUCAPACITY | \ + SD_SHARE_CLS_RESOURCES | \ SD_SHARE_PKG_RESOURCES | \ SD_NUMA | \ SD_ASYM_PACKING) @@ -1480,6 +1481,11 @@ static void claim_allocations(int cpu, struct sched_domain *sd) #ifdef CONFIG_SCHED_SMT { cpu_smt_mask, cpu_smt_flags, SD_INIT_NAME(SMT) }, #endif + +#ifdef CONFIG_SCHED_CLUSTER + { cpu_clustergroup_mask, cpu_cluster_flags, SD_INIT_NAME(CLS) }, +#endif + #ifdef CONFIG_SCHED_MC { cpu_coregroup_mask, cpu_core_flags, SD_INIT_NAME(MC) }, #endif From patchwork Mon Mar 1 22:59:40 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Song Bao Hua (Barry Song)" X-Patchwork-Id: 12110751 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=-16.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 8F528C433E9 for ; Mon, 1 Mar 2021 23:07:43 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 4EE5F60240 for ; Mon, 1 Mar 2021 23:07:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4EE5F60240 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=hisilicon.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Message-ID:Date: Subject:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=oP+aNZ3J3H2bSVkvMatRu6UI25cKNyXnNEoCfa1yrXs=; b=OBEK43V8ttvui6S34r93uiZIX MKq5Qb77k6IPB3C6wUnddjEPEXTn4G7FLNPW+NR9AdN/fxhDg8NoPZ1rtwRn7UWWJXZUfwP+MXlSa gtRDWgABUXjotR5YQQ+QTi2Hb49ws/usGsVMT3gt6pqs/q1kfCg0qg7m//nasmZZqSz8iWaWXKY3d VBdg2UWn/C8NxhTWpiWdgJCJHrarCGPvBtUGZYDa/yfWSRkI7wO2Ru7c0yBErDxbsfBoXO1DBISfY WgxevOd4JcIJZ6mNmkPIPk0Ht2eUe/QyDsLU7NwXXequS+IzRfgNMs7+ph8IBSGH4cR14xc2nlmfZ 7yXsP1CTA==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1lGrcU-0002XB-Vb; Mon, 01 Mar 2021 23:06:31 +0000 Received: from szxga04-in.huawei.com ([45.249.212.190]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1lGrcR-0002VN-Gq for linux-arm-kernel@lists.infradead.org; Mon, 01 Mar 2021 23:06:29 +0000 Received: from DGGEMS412-HUB.china.huawei.com (unknown [172.30.72.58]) by szxga04-in.huawei.com (SkyGuard) with ESMTP id 4DqG6z6fBrz16FB5; Tue, 2 Mar 2021 07:04:43 +0800 (CST) Received: from SWX921481.china.huawei.com (10.126.203.209) by DGGEMS412-HUB.china.huawei.com (10.3.19.212) with Microsoft SMTP Server id 14.3.498.0; Tue, 2 Mar 2021 07:06:16 +0800 From: Barry Song To: , , , , , , , , , , , , , Subject: [RFC PATCH v4 3/3] scheduler: Add cluster scheduler level for x86 Date: Tue, 2 Mar 2021 11:59:40 +1300 Message-ID: <20210301225940.16728-4-song.bao.hua@hisilicon.com> X-Mailer: git-send-email 2.21.0.windows.1 In-Reply-To: <20210301225940.16728-1-song.bao.hua@hisilicon.com> References: <20210301225940.16728-1-song.bao.hua@hisilicon.com> MIME-Version: 1.0 X-Originating-IP: [10.126.203.209] X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210301_180628_153900_055FFF20 X-CRM114-Status: GOOD ( 17.84 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: juri.lelli@redhat.com, mark.rutland@arm.com, aubrey.li@linux.intel.com, hpa@zytor.com, prime.zeng@hisilicon.com, guodong.xu@linaro.org, gregkh@linuxfoundation.org, sudeep.holla@arm.com, linux-kernel@vger.kernel.org, linuxarm@openeuler.org, linux-acpi@vger.kernel.org, xuwei5@huawei.com, jonathan.cameron@huawei.com, yangyicong@huawei.com, x86@kernel.org, msys.mizuma@gmail.com, liguozhu@hisilicon.com, valentin.schneider@arm.com, linux-arm-kernel@lists.infradead.org, Barry Song Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Tim Chen There are x86 CPU architectures (e.g. Jacobsville) where L2 cahce is shared among a cluster of cores instead of being exclusive to one single core. To prevent oversubscription of L2 cache, load should be balanced between such L2 clusters, especially for tasks with no shared data. Also with cluster scheduling policy where tasks are woken up in the same L2 cluster, we will benefit from keeping tasks related to each other and likely sharing data in the same L2 cluster. Add CPU masks of CPUs sharing the L2 cache so we can build such L2 cluster scheduler domain. Signed-off-by: Tim Chen Signed-off-by: Barry Song --- arch/x86/Kconfig | 8 ++++++++ arch/x86/include/asm/smp.h | 7 +++++++ arch/x86/include/asm/topology.h | 1 + arch/x86/kernel/cpu/cacheinfo.c | 1 + arch/x86/kernel/cpu/common.c | 3 +++ arch/x86/kernel/smpboot.c | 43 ++++++++++++++++++++++++++++++++++++++++- 6 files changed, 62 insertions(+), 1 deletion(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index d3338a8..40110de 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1009,6 +1009,14 @@ config NR_CPUS This is purely to save memory: each supported CPU adds about 8KB to the kernel image. +config SCHED_CLUSTER + bool "Cluster scheduler support" + default n + help + Cluster scheduler support improves the CPU scheduler's decision + making when dealing with machines that have clusters of CPUs + sharing L2 cache. If unsure say N here. + config SCHED_SMT def_bool y if SMP diff --git a/arch/x86/include/asm/smp.h b/arch/x86/include/asm/smp.h index c0538f8..9cbc4ae 100644 --- a/arch/x86/include/asm/smp.h +++ b/arch/x86/include/asm/smp.h @@ -16,7 +16,9 @@ DECLARE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_die_map); /* cpus sharing the last level cache: */ DECLARE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_llc_shared_map); +DECLARE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_l2c_shared_map); DECLARE_PER_CPU_READ_MOSTLY(u16, cpu_llc_id); +DECLARE_PER_CPU_READ_MOSTLY(u16, cpu_l2c_id); DECLARE_PER_CPU_READ_MOSTLY(int, cpu_number); static inline struct cpumask *cpu_llc_shared_mask(int cpu) @@ -24,6 +26,11 @@ static inline struct cpumask *cpu_llc_shared_mask(int cpu) return per_cpu(cpu_llc_shared_map, cpu); } +static inline struct cpumask *cpu_l2c_shared_mask(int cpu) +{ + return per_cpu(cpu_l2c_shared_map, cpu); +} + DECLARE_EARLY_PER_CPU_READ_MOSTLY(u16, x86_cpu_to_apicid); DECLARE_EARLY_PER_CPU_READ_MOSTLY(u32, x86_cpu_to_acpiid); DECLARE_EARLY_PER_CPU_READ_MOSTLY(u16, x86_bios_cpu_apicid); diff --git a/arch/x86/include/asm/topology.h b/arch/x86/include/asm/topology.h index 9239399..2a11ccc 100644 --- a/arch/x86/include/asm/topology.h +++ b/arch/x86/include/asm/topology.h @@ -103,6 +103,7 @@ static inline void setup_node_to_cpumask_map(void) { } #include extern const struct cpumask *cpu_coregroup_mask(int cpu); +extern const struct cpumask *cpu_clustergroup_mask(int cpu); #define topology_logical_package_id(cpu) (cpu_data(cpu).logical_proc_id) #define topology_physical_package_id(cpu) (cpu_data(cpu).phys_proc_id) diff --git a/arch/x86/kernel/cpu/cacheinfo.c b/arch/x86/kernel/cpu/cacheinfo.c index 3ca9be4..0d03a71 100644 --- a/arch/x86/kernel/cpu/cacheinfo.c +++ b/arch/x86/kernel/cpu/cacheinfo.c @@ -846,6 +846,7 @@ void init_intel_cacheinfo(struct cpuinfo_x86 *c) l2 = new_l2; #ifdef CONFIG_SMP per_cpu(cpu_llc_id, cpu) = l2_id; + per_cpu(cpu_l2c_id, cpu) = l2_id; #endif } diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 35ad848..fb08c73 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -78,6 +78,9 @@ /* Last level cache ID of each logical CPU */ DEFINE_PER_CPU_READ_MOSTLY(u16, cpu_llc_id) = BAD_APICID; +/* L2 cache ID of each logical CPU */ +DEFINE_PER_CPU_READ_MOSTLY(u16, cpu_l2c_id) = BAD_APICID; + /* correctly size the local cpu masks */ void __init setup_cpu_local_masks(void) { diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index 02813a7..c85ffa8 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -101,6 +101,8 @@ DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_llc_shared_map); +DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_l2c_shared_map); + /* Per CPU bogomips and other parameters */ DEFINE_PER_CPU_READ_MOSTLY(struct cpuinfo_x86, cpu_info); EXPORT_PER_CPU_SYMBOL(cpu_info); @@ -501,6 +503,21 @@ static bool match_llc(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o) return topology_sane(c, o, "llc"); } +static bool match_l2c(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o) +{ + int cpu1 = c->cpu_index, cpu2 = o->cpu_index; + + /* Do not match if we do not have a valid APICID for cpu: */ + if (per_cpu(cpu_l2c_id, cpu1) == BAD_APICID) + return false; + + /* Do not match if L2 cache id does not match: */ + if (per_cpu(cpu_l2c_id, cpu1) != per_cpu(cpu_l2c_id, cpu2)) + return false; + + return topology_sane(c, o, "l2c"); +} + /* * Unlike the other levels, we do not enforce keeping a * multicore group inside a NUMA node. If this happens, we will @@ -522,7 +539,7 @@ static bool match_die(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o) } -#if defined(CONFIG_SCHED_SMT) || defined(CONFIG_SCHED_MC) +#if defined(CONFIG_SCHED_SMT) || defined(CONFIG_SCHED_CLUSTER) || defined(CONFIG_SCHED_MC) static inline int x86_sched_itmt_flags(void) { return sysctl_sched_itmt_enabled ? SD_ASYM_PACKING : 0; @@ -540,12 +557,21 @@ static int x86_smt_flags(void) return cpu_smt_flags() | x86_sched_itmt_flags(); } #endif +#ifdef CONFIG_SCHED_CLUSTER +static int x86_cluster_flags(void) +{ + return cpu_cluster_flags() | x86_sched_itmt_flags(); +} +#endif #endif static struct sched_domain_topology_level x86_numa_in_package_topology[] = { #ifdef CONFIG_SCHED_SMT { cpu_smt_mask, x86_smt_flags, SD_INIT_NAME(SMT) }, #endif +#ifdef CONFIG_SCHED_CLUSTER + { cpu_clustergroup_mask, x86_cluster_flags, SD_INIT_NAME(CLS) }, +#endif #ifdef CONFIG_SCHED_MC { cpu_coregroup_mask, x86_core_flags, SD_INIT_NAME(MC) }, #endif @@ -556,6 +582,9 @@ static int x86_smt_flags(void) #ifdef CONFIG_SCHED_SMT { cpu_smt_mask, x86_smt_flags, SD_INIT_NAME(SMT) }, #endif +#ifdef CONFIG_SCHED_CLUSTER + { cpu_clustergroup_mask, x86_cluster_flags, SD_INIT_NAME(CLS) }, +#endif #ifdef CONFIG_SCHED_MC { cpu_coregroup_mask, x86_core_flags, SD_INIT_NAME(MC) }, #endif @@ -583,6 +612,7 @@ void set_cpu_sibling_map(int cpu) if (!has_mp) { cpumask_set_cpu(cpu, topology_sibling_cpumask(cpu)); cpumask_set_cpu(cpu, cpu_llc_shared_mask(cpu)); + cpumask_set_cpu(cpu, cpu_l2c_shared_mask(cpu)); cpumask_set_cpu(cpu, topology_core_cpumask(cpu)); cpumask_set_cpu(cpu, topology_die_cpumask(cpu)); c->booted_cores = 1; @@ -598,6 +628,8 @@ void set_cpu_sibling_map(int cpu) if ((i == cpu) || (has_mp && match_llc(c, o))) link_mask(cpu_llc_shared_mask, cpu, i); + if ((i == cpu) || (has_mp && match_l2c(c, o))) + link_mask(cpu_l2c_shared_mask, cpu, i); } /* @@ -649,6 +681,11 @@ const struct cpumask *cpu_coregroup_mask(int cpu) return cpu_llc_shared_mask(cpu); } +const struct cpumask *cpu_clustergroup_mask(int cpu) +{ + return cpu_l2c_shared_mask(cpu); +} + static void impress_friends(void) { int cpu; @@ -1332,6 +1369,7 @@ void __init native_smp_prepare_cpus(unsigned int max_cpus) zalloc_cpumask_var(&per_cpu(cpu_core_map, i), GFP_KERNEL); zalloc_cpumask_var(&per_cpu(cpu_die_map, i), GFP_KERNEL); zalloc_cpumask_var(&per_cpu(cpu_llc_shared_map, i), GFP_KERNEL); + zalloc_cpumask_var(&per_cpu(cpu_l2c_shared_map, i), GFP_KERNEL); } /* @@ -1556,7 +1594,10 @@ static void remove_siblinginfo(int cpu) cpumask_clear_cpu(cpu, topology_sibling_cpumask(sibling)); for_each_cpu(sibling, cpu_llc_shared_mask(cpu)) cpumask_clear_cpu(cpu, cpu_llc_shared_mask(sibling)); + for_each_cpu(sibling, cpu_l2c_shared_mask(cpu)) + cpumask_clear_cpu(cpu, cpu_l2c_shared_mask(sibling)); cpumask_clear(cpu_llc_shared_mask(cpu)); + cpumask_clear(cpu_l2c_shared_mask(cpu)); cpumask_clear(topology_sibling_cpumask(cpu)); cpumask_clear(topology_core_cpumask(cpu)); cpumask_clear(topology_die_cpumask(cpu));