From: Kajol Jain <kjain@linux.ibm.com> To: mpe@ellerman.id.au, linuxppc-dev@lists.ozlabs.org, nvdimm@lists.linux.dev, linux-kernel@vger.kernel.org, peterz@infradead.org Cc: maddy@linux.vnet.ibm.com, santosh@fossix.org, aneesh.kumar@linux.ibm.com, vaibhav@linux.ibm.com, dan.j.williams@intel.com, ira.weiny@intel.com, atrajeev@linux.vnet.ibm.com, tglx@linutronix.de, kjain@linux.ibm.com, rnsastry@linux.ibm.com Subject: [PATCH 2/4] drivers/nvdimm: Add perf interface to expose nvdimm performance stats Date: Tue, 8 Jun 2021 17:26:58 +0530 [thread overview] Message-ID: <20210608115700.85933-3-kjain@linux.ibm.com> (raw) In-Reply-To: <20210608115700.85933-1-kjain@linux.ibm.com> A common interface is added to get performance stats reporting support for nvdimm devices. Added interface includes support for pmu register/unregister functions, cpu hotplug and pmu event functions like event_init/add/read/del. User could use the standard perf tool to access perf events exposed via pmu. Signed-off-by: Kajol Jain <kjain@linux.ibm.com> --- drivers/nvdimm/Makefile | 1 + drivers/nvdimm/nd_perf.c | 230 +++++++++++++++++++++++++++++++++++++++ include/linux/nd.h | 3 + 3 files changed, 234 insertions(+) create mode 100644 drivers/nvdimm/nd_perf.c diff --git a/drivers/nvdimm/Makefile b/drivers/nvdimm/Makefile index 29203f3d3069..25dba6095612 100644 --- a/drivers/nvdimm/Makefile +++ b/drivers/nvdimm/Makefile @@ -18,6 +18,7 @@ nd_e820-y := e820.o libnvdimm-y := core.o libnvdimm-y += bus.o libnvdimm-y += dimm_devs.o +libnvdimm-y += nd_perf.o libnvdimm-y += dimm.o libnvdimm-y += region_devs.o libnvdimm-y += region.o diff --git a/drivers/nvdimm/nd_perf.c b/drivers/nvdimm/nd_perf.c new file mode 100644 index 000000000000..5cc1f1c65972 --- /dev/null +++ b/drivers/nvdimm/nd_perf.c @@ -0,0 +1,230 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * nd_perf.c: NVDIMM Device Performance Monitoring Unit support + * + * Perf interface to expose nvdimm performance stats. + * + * Copyright (C) 2021 IBM Corporation + */ + +#define pr_fmt(fmt) "nvdimm_pmu: " fmt + +#include <linux/nd.h> + +static ssize_t nvdimm_pmu_cpumask_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct pmu *pmu = dev_get_drvdata(dev); + struct nvdimm_pmu *nd_pmu; + + nd_pmu = container_of(pmu, struct nvdimm_pmu, pmu); + + return cpumap_print_to_pagebuf(true, buf, cpumask_of(nd_pmu->cpu)); +} + +static int nvdimm_pmu_cpu_offline(unsigned int cpu, struct hlist_node *node) +{ + struct nvdimm_pmu *nd_pmu; + u32 target; + int nodeid; + const struct cpumask *cpumask; + + nd_pmu = hlist_entry_safe(node, struct nvdimm_pmu, node); + + /* Clear it, incase given cpu is set in nd_pmu->arch_cpumask */ + cpumask_test_and_clear_cpu(cpu, &nd_pmu->arch_cpumask); + + /* + * If given cpu is not same as current designated cpu for + * counter access, just return. + */ + if (cpu != nd_pmu->cpu) + return 0; + + /* Check for any active cpu in nd_pmu->arch_cpumask */ + target = cpumask_any(&nd_pmu->arch_cpumask); + nd_pmu->cpu = target; + + /* + * Incase we don't have any active cpu in nd_pmu->arch_cpumask, + * check in given cpu's numa node list. + */ + if (target >= nr_cpu_ids) { + nodeid = cpu_to_node(cpu); + cpumask = cpumask_of_node(nodeid); + target = cpumask_any_but(cpumask, cpu); + nd_pmu->cpu = target; + + if (target >= nr_cpu_ids) + return -1; + } + + return 0; +} + +static int nvdimm_pmu_cpu_online(unsigned int cpu, struct hlist_node *node) +{ + struct nvdimm_pmu *nd_pmu; + + nd_pmu = hlist_entry_safe(node, struct nvdimm_pmu, node); + + if (nd_pmu->cpu >= nr_cpu_ids) + nd_pmu->cpu = cpu; + + return 0; +} + +static int create_cpumask_attr_group(struct nvdimm_pmu *nd_pmu) +{ + struct perf_pmu_events_attr *attr; + struct attribute **attrs; + struct attribute_group *nvdimm_pmu_cpumask_group; + + attr = kzalloc(sizeof(*attr), GFP_KERNEL); + if (!attr) + return -ENOMEM; + + attrs = kzalloc(2 * sizeof(struct attribute *), GFP_KERNEL); + if (!attrs) { + kfree(attr); + return -ENOMEM; + } + + /* Allocate memory for cpumask attribute group */ + nvdimm_pmu_cpumask_group = kzalloc(sizeof(*nvdimm_pmu_cpumask_group), GFP_KERNEL); + if (!nvdimm_pmu_cpumask_group) { + kfree(attr); + kfree(attrs); + return -ENOMEM; + } + + sysfs_attr_init(&attr->attr.attr); + attr->attr.attr.name = "cpumask"; + attr->attr.attr.mode = 0444; + attr->attr.show = nvdimm_pmu_cpumask_show; + attrs[0] = &attr->attr.attr; + attrs[1] = NULL; + + nvdimm_pmu_cpumask_group->attrs = attrs; + nd_pmu->attr_groups[NVDIMM_PMU_CPUMASK_ATTR] = nvdimm_pmu_cpumask_group; + return 0; +} + +static int nvdimm_pmu_cpu_hotplug_init(struct nvdimm_pmu *nd_pmu) +{ + int nodeid, rc; + const struct cpumask *cpumask; + + /* + * Incase cpu hotplug is not handled by arch specific code + * they can still provide required cpumask which can be used + * to get designatd cpu for counter access. + * Check for any active cpu in nd_pmu->arch_cpumask. + */ + if (!cpumask_empty(&nd_pmu->arch_cpumask)) { + nd_pmu->cpu = cpumask_any(&nd_pmu->arch_cpumask); + } else { + /* pick active cpu from the cpumask of device numa node. */ + nodeid = dev_to_node(nd_pmu->dev); + cpumask = cpumask_of_node(nodeid); + nd_pmu->cpu = cpumask_any(cpumask); + } + + rc = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "perf/nvdimm:online", + nvdimm_pmu_cpu_online, nvdimm_pmu_cpu_offline); + + if (rc < 0) + return rc; + + nd_pmu->cpuhp_state = rc; + + /* Register the pmu instance for cpu hotplug */ + rc = cpuhp_state_add_instance_nocalls(nd_pmu->cpuhp_state, &nd_pmu->node); + if (rc) { + cpuhp_remove_multi_state(nd_pmu->cpuhp_state); + return rc; + } + + /* Create cpumask attribute group */ + rc = create_cpumask_attr_group(nd_pmu); + if (rc) { + cpuhp_state_remove_instance_nocalls(nd_pmu->cpuhp_state, &nd_pmu->node); + cpuhp_remove_multi_state(nd_pmu->cpuhp_state); + return rc; + } + + return 0; +} + +void nvdimm_pmu_free_hotplug_memory(struct nvdimm_pmu *nd_pmu) +{ + cpuhp_state_remove_instance_nocalls(nd_pmu->cpuhp_state, &nd_pmu->node); + cpuhp_remove_multi_state(nd_pmu->cpuhp_state); + + if (nd_pmu->attr_groups[NVDIMM_PMU_CPUMASK_ATTR]) + kfree(nd_pmu->attr_groups[NVDIMM_PMU_CPUMASK_ATTR]->attrs); + kfree(nd_pmu->attr_groups[NVDIMM_PMU_CPUMASK_ATTR]); +} + +int register_nvdimm_pmu(struct nvdimm_pmu *nd_pmu, struct platform_device *pdev) +{ + int rc; + + if (!nd_pmu || !pdev) + return -EINVAL; + + /* event functions like add/del/read/event_init should not be NULL */ + if (WARN_ON_ONCE(!(nd_pmu->event_init && nd_pmu->add && nd_pmu->del && nd_pmu->read))) + return -EINVAL; + + nd_pmu->pmu.task_ctx_nr = perf_invalid_context; + nd_pmu->pmu.name = nd_pmu->name; + nd_pmu->pmu.event_init = nd_pmu->event_init; + nd_pmu->pmu.add = nd_pmu->add; + nd_pmu->pmu.del = nd_pmu->del; + nd_pmu->pmu.read = nd_pmu->read; + + nd_pmu->pmu.attr_groups = nd_pmu->attr_groups; + nd_pmu->pmu.capabilities = PERF_PMU_CAP_NO_INTERRUPT | + PERF_PMU_CAP_NO_EXCLUDE; + + /* + * Add platform_device->dev pointer to nvdimm_pmu to access + * device data in events functions. + */ + nd_pmu->dev = &pdev->dev; + + /* + * Incase cpumask attribute is set it means cpu + * hotplug is handled by the arch specific code and + * we can skip calling hotplug_init. + */ + if (!nd_pmu->attr_groups[NVDIMM_PMU_CPUMASK_ATTR]) { + /* init cpuhotplug */ + rc = nvdimm_pmu_cpu_hotplug_init(nd_pmu); + if (rc) { + pr_info("cpu hotplug feature failed for device: %s\n", nd_pmu->name); + return rc; + } + } + + rc = perf_pmu_register(&nd_pmu->pmu, nd_pmu->name, -1); + if (rc) { + nvdimm_pmu_free_hotplug_memory(nd_pmu); + return rc; + } + + pr_info("%s NVDIMM performance monitor support registered\n", + nd_pmu->name); + + return 0; +} +EXPORT_SYMBOL_GPL(register_nvdimm_pmu); + +void unregister_nvdimm_pmu(struct nvdimm_pmu *nd_pmu) +{ + /* handle freeing of memory nd_pmu in arch specific code */ + perf_pmu_unregister(&nd_pmu->pmu); + nvdimm_pmu_free_hotplug_memory(nd_pmu); +} +EXPORT_SYMBOL_GPL(unregister_nvdimm_pmu); diff --git a/include/linux/nd.h b/include/linux/nd.h index 712499cf7335..7d8b4f7d277d 100644 --- a/include/linux/nd.h +++ b/include/linux/nd.h @@ -66,6 +66,9 @@ struct nvdimm_pmu { struct cpumask arch_cpumask; }; +int register_nvdimm_pmu(struct nvdimm_pmu *nvdimm, struct platform_device *pdev); +void unregister_nvdimm_pmu(struct nvdimm_pmu *nd_pmu); + struct nd_device_driver { struct device_driver drv; unsigned long type; -- 2.27.0
WARNING: multiple messages have this Message-ID (diff)
From: Kajol Jain <kjain@linux.ibm.com> To: mpe@ellerman.id.au, linuxppc-dev@lists.ozlabs.org, nvdimm@lists.linux.dev, linux-kernel@vger.kernel.org, peterz@infradead.org Cc: santosh@fossix.org, maddy@linux.vnet.ibm.com, rnsastry@linux.ibm.com, aneesh.kumar@linux.ibm.com, atrajeev@linux.vnet.ibm.com, kjain@linux.ibm.com, vaibhav@linux.ibm.com, dan.j.williams@intel.com, ira.weiny@intel.com, tglx@linutronix.de Subject: [PATCH 2/4] drivers/nvdimm: Add perf interface to expose nvdimm performance stats Date: Tue, 8 Jun 2021 17:26:58 +0530 [thread overview] Message-ID: <20210608115700.85933-3-kjain@linux.ibm.com> (raw) In-Reply-To: <20210608115700.85933-1-kjain@linux.ibm.com> A common interface is added to get performance stats reporting support for nvdimm devices. Added interface includes support for pmu register/unregister functions, cpu hotplug and pmu event functions like event_init/add/read/del. User could use the standard perf tool to access perf events exposed via pmu. Signed-off-by: Kajol Jain <kjain@linux.ibm.com> --- drivers/nvdimm/Makefile | 1 + drivers/nvdimm/nd_perf.c | 230 +++++++++++++++++++++++++++++++++++++++ include/linux/nd.h | 3 + 3 files changed, 234 insertions(+) create mode 100644 drivers/nvdimm/nd_perf.c diff --git a/drivers/nvdimm/Makefile b/drivers/nvdimm/Makefile index 29203f3d3069..25dba6095612 100644 --- a/drivers/nvdimm/Makefile +++ b/drivers/nvdimm/Makefile @@ -18,6 +18,7 @@ nd_e820-y := e820.o libnvdimm-y := core.o libnvdimm-y += bus.o libnvdimm-y += dimm_devs.o +libnvdimm-y += nd_perf.o libnvdimm-y += dimm.o libnvdimm-y += region_devs.o libnvdimm-y += region.o diff --git a/drivers/nvdimm/nd_perf.c b/drivers/nvdimm/nd_perf.c new file mode 100644 index 000000000000..5cc1f1c65972 --- /dev/null +++ b/drivers/nvdimm/nd_perf.c @@ -0,0 +1,230 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * nd_perf.c: NVDIMM Device Performance Monitoring Unit support + * + * Perf interface to expose nvdimm performance stats. + * + * Copyright (C) 2021 IBM Corporation + */ + +#define pr_fmt(fmt) "nvdimm_pmu: " fmt + +#include <linux/nd.h> + +static ssize_t nvdimm_pmu_cpumask_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct pmu *pmu = dev_get_drvdata(dev); + struct nvdimm_pmu *nd_pmu; + + nd_pmu = container_of(pmu, struct nvdimm_pmu, pmu); + + return cpumap_print_to_pagebuf(true, buf, cpumask_of(nd_pmu->cpu)); +} + +static int nvdimm_pmu_cpu_offline(unsigned int cpu, struct hlist_node *node) +{ + struct nvdimm_pmu *nd_pmu; + u32 target; + int nodeid; + const struct cpumask *cpumask; + + nd_pmu = hlist_entry_safe(node, struct nvdimm_pmu, node); + + /* Clear it, incase given cpu is set in nd_pmu->arch_cpumask */ + cpumask_test_and_clear_cpu(cpu, &nd_pmu->arch_cpumask); + + /* + * If given cpu is not same as current designated cpu for + * counter access, just return. + */ + if (cpu != nd_pmu->cpu) + return 0; + + /* Check for any active cpu in nd_pmu->arch_cpumask */ + target = cpumask_any(&nd_pmu->arch_cpumask); + nd_pmu->cpu = target; + + /* + * Incase we don't have any active cpu in nd_pmu->arch_cpumask, + * check in given cpu's numa node list. + */ + if (target >= nr_cpu_ids) { + nodeid = cpu_to_node(cpu); + cpumask = cpumask_of_node(nodeid); + target = cpumask_any_but(cpumask, cpu); + nd_pmu->cpu = target; + + if (target >= nr_cpu_ids) + return -1; + } + + return 0; +} + +static int nvdimm_pmu_cpu_online(unsigned int cpu, struct hlist_node *node) +{ + struct nvdimm_pmu *nd_pmu; + + nd_pmu = hlist_entry_safe(node, struct nvdimm_pmu, node); + + if (nd_pmu->cpu >= nr_cpu_ids) + nd_pmu->cpu = cpu; + + return 0; +} + +static int create_cpumask_attr_group(struct nvdimm_pmu *nd_pmu) +{ + struct perf_pmu_events_attr *attr; + struct attribute **attrs; + struct attribute_group *nvdimm_pmu_cpumask_group; + + attr = kzalloc(sizeof(*attr), GFP_KERNEL); + if (!attr) + return -ENOMEM; + + attrs = kzalloc(2 * sizeof(struct attribute *), GFP_KERNEL); + if (!attrs) { + kfree(attr); + return -ENOMEM; + } + + /* Allocate memory for cpumask attribute group */ + nvdimm_pmu_cpumask_group = kzalloc(sizeof(*nvdimm_pmu_cpumask_group), GFP_KERNEL); + if (!nvdimm_pmu_cpumask_group) { + kfree(attr); + kfree(attrs); + return -ENOMEM; + } + + sysfs_attr_init(&attr->attr.attr); + attr->attr.attr.name = "cpumask"; + attr->attr.attr.mode = 0444; + attr->attr.show = nvdimm_pmu_cpumask_show; + attrs[0] = &attr->attr.attr; + attrs[1] = NULL; + + nvdimm_pmu_cpumask_group->attrs = attrs; + nd_pmu->attr_groups[NVDIMM_PMU_CPUMASK_ATTR] = nvdimm_pmu_cpumask_group; + return 0; +} + +static int nvdimm_pmu_cpu_hotplug_init(struct nvdimm_pmu *nd_pmu) +{ + int nodeid, rc; + const struct cpumask *cpumask; + + /* + * Incase cpu hotplug is not handled by arch specific code + * they can still provide required cpumask which can be used + * to get designatd cpu for counter access. + * Check for any active cpu in nd_pmu->arch_cpumask. + */ + if (!cpumask_empty(&nd_pmu->arch_cpumask)) { + nd_pmu->cpu = cpumask_any(&nd_pmu->arch_cpumask); + } else { + /* pick active cpu from the cpumask of device numa node. */ + nodeid = dev_to_node(nd_pmu->dev); + cpumask = cpumask_of_node(nodeid); + nd_pmu->cpu = cpumask_any(cpumask); + } + + rc = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "perf/nvdimm:online", + nvdimm_pmu_cpu_online, nvdimm_pmu_cpu_offline); + + if (rc < 0) + return rc; + + nd_pmu->cpuhp_state = rc; + + /* Register the pmu instance for cpu hotplug */ + rc = cpuhp_state_add_instance_nocalls(nd_pmu->cpuhp_state, &nd_pmu->node); + if (rc) { + cpuhp_remove_multi_state(nd_pmu->cpuhp_state); + return rc; + } + + /* Create cpumask attribute group */ + rc = create_cpumask_attr_group(nd_pmu); + if (rc) { + cpuhp_state_remove_instance_nocalls(nd_pmu->cpuhp_state, &nd_pmu->node); + cpuhp_remove_multi_state(nd_pmu->cpuhp_state); + return rc; + } + + return 0; +} + +void nvdimm_pmu_free_hotplug_memory(struct nvdimm_pmu *nd_pmu) +{ + cpuhp_state_remove_instance_nocalls(nd_pmu->cpuhp_state, &nd_pmu->node); + cpuhp_remove_multi_state(nd_pmu->cpuhp_state); + + if (nd_pmu->attr_groups[NVDIMM_PMU_CPUMASK_ATTR]) + kfree(nd_pmu->attr_groups[NVDIMM_PMU_CPUMASK_ATTR]->attrs); + kfree(nd_pmu->attr_groups[NVDIMM_PMU_CPUMASK_ATTR]); +} + +int register_nvdimm_pmu(struct nvdimm_pmu *nd_pmu, struct platform_device *pdev) +{ + int rc; + + if (!nd_pmu || !pdev) + return -EINVAL; + + /* event functions like add/del/read/event_init should not be NULL */ + if (WARN_ON_ONCE(!(nd_pmu->event_init && nd_pmu->add && nd_pmu->del && nd_pmu->read))) + return -EINVAL; + + nd_pmu->pmu.task_ctx_nr = perf_invalid_context; + nd_pmu->pmu.name = nd_pmu->name; + nd_pmu->pmu.event_init = nd_pmu->event_init; + nd_pmu->pmu.add = nd_pmu->add; + nd_pmu->pmu.del = nd_pmu->del; + nd_pmu->pmu.read = nd_pmu->read; + + nd_pmu->pmu.attr_groups = nd_pmu->attr_groups; + nd_pmu->pmu.capabilities = PERF_PMU_CAP_NO_INTERRUPT | + PERF_PMU_CAP_NO_EXCLUDE; + + /* + * Add platform_device->dev pointer to nvdimm_pmu to access + * device data in events functions. + */ + nd_pmu->dev = &pdev->dev; + + /* + * Incase cpumask attribute is set it means cpu + * hotplug is handled by the arch specific code and + * we can skip calling hotplug_init. + */ + if (!nd_pmu->attr_groups[NVDIMM_PMU_CPUMASK_ATTR]) { + /* init cpuhotplug */ + rc = nvdimm_pmu_cpu_hotplug_init(nd_pmu); + if (rc) { + pr_info("cpu hotplug feature failed for device: %s\n", nd_pmu->name); + return rc; + } + } + + rc = perf_pmu_register(&nd_pmu->pmu, nd_pmu->name, -1); + if (rc) { + nvdimm_pmu_free_hotplug_memory(nd_pmu); + return rc; + } + + pr_info("%s NVDIMM performance monitor support registered\n", + nd_pmu->name); + + return 0; +} +EXPORT_SYMBOL_GPL(register_nvdimm_pmu); + +void unregister_nvdimm_pmu(struct nvdimm_pmu *nd_pmu) +{ + /* handle freeing of memory nd_pmu in arch specific code */ + perf_pmu_unregister(&nd_pmu->pmu); + nvdimm_pmu_free_hotplug_memory(nd_pmu); +} +EXPORT_SYMBOL_GPL(unregister_nvdimm_pmu); diff --git a/include/linux/nd.h b/include/linux/nd.h index 712499cf7335..7d8b4f7d277d 100644 --- a/include/linux/nd.h +++ b/include/linux/nd.h @@ -66,6 +66,9 @@ struct nvdimm_pmu { struct cpumask arch_cpumask; }; +int register_nvdimm_pmu(struct nvdimm_pmu *nvdimm, struct platform_device *pdev); +void unregister_nvdimm_pmu(struct nvdimm_pmu *nd_pmu); + struct nd_device_driver { struct device_driver drv; unsigned long type; -- 2.27.0
next prev parent reply other threads:[~2021-06-08 11:58 UTC|newest] Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-06-08 11:56 [PATCH 0/4] Add perf interface to expose nvdimm Kajol Jain 2021-06-08 11:56 ` Kajol Jain 2021-06-08 11:56 ` [PATCH 1/4] drivers/nvdimm: Add nvdimm pmu structure Kajol Jain 2021-06-08 11:56 ` Kajol Jain 2021-06-08 11:56 ` Kajol Jain [this message] 2021-06-08 11:56 ` [PATCH 2/4] drivers/nvdimm: Add perf interface to expose nvdimm performance stats Kajol Jain 2021-06-08 17:36 ` Peter Zijlstra 2021-06-08 17:36 ` Peter Zijlstra 2021-06-09 12:12 ` kajoljain 2021-06-09 12:12 ` kajoljain 2021-06-08 11:56 ` [PATCH 3/4] powerpc/papr_scm: Add perf interface support Kajol Jain 2021-06-08 11:56 ` Kajol Jain 2021-06-08 11:57 ` [PATCH 4/4] powerpc/papr_scm: Document papr_scm sysfs event format entries Kajol Jain 2021-06-08 11:57 ` Kajol Jain
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