From 4c08d4bbc089a95f3f38389c2b79dbc6ab24f10b Mon Sep 17 00:00:00 2001 From: Kajol Jain Date: Fri, 25 Feb 2022 20:00:23 +0530 Subject: [PATCH] powerpc/papr_scm: Add perf interface support Performance monitoring support for papr-scm nvdimm devices via perf interface is added which includes addition of pmu functions like add/del/read/event_init for nvdimm_pmu struture. A new parameter 'priv' in added to the pdev_archdata structure to save nvdimm_pmu device pointer, to handle the unregistering of pmu device. papr_scm_pmu_register function populates the nvdimm_pmu structure with name, capabilities, cpumask along with event handling functions. Finally the populated nvdimm_pmu structure is passed to register the pmu device. Event handling functions internally uses hcall to get events and counter data. Result in power9 machine with 2 nvdimm device: Ex: List all event by perf list command:# perf list nmem nmem0/cache_rh_cnt/ [Kernel PMU event] nmem0/cache_wh_cnt/ [Kernel PMU event] nmem0/cri_res_util/ [Kernel PMU event] nmem0/ctl_res_cnt/ [Kernel PMU event] nmem0/ctl_res_tm/ [Kernel PMU event] nmem0/fast_w_cnt/ [Kernel PMU event] nmem0/host_l_cnt/ [Kernel PMU event] nmem0/host_l_dur/ [Kernel PMU event] nmem0/host_s_cnt/ [Kernel PMU event] nmem0/host_s_dur/ [Kernel PMU event] nmem0/med_r_cnt/ [Kernel PMU event] nmem0/med_r_dur/ [Kernel PMU event] nmem0/med_w_cnt/ [Kernel PMU event] nmem0/med_w_dur/ [Kernel PMU event] nmem0/mem_life/ [Kernel PMU event] nmem0/poweron_secs/ [Kernel PMU event] ... nmem1/mem_life/ [Kernel PMU event] nmem1/poweron_secs/ [Kernel PMU event] Acked-by: Peter Zijlstra (Intel) Tested-by: Nageswara R Sastry Signed-off-by: Kajol Jain [Add numa_map_to_online_node function call to get online node id] Reported-by: Nageswara R Sastry Reviewed-by: Madhavan Srinivasan Link: https://lore.kernel.org/r/20220225143024.47947-4-kjain@linux.ibm.com Signed-off-by: Dan Williams --- arch/powerpc/include/asm/device.h | 5 + arch/powerpc/platforms/pseries/papr_scm.c | 225 ++++++++++++++++++++++++++++++ 2 files changed, 230 insertions(+) diff --git a/arch/powerpc/include/asm/device.h b/arch/powerpc/include/asm/device.h index 219559d..47ed639 100644 --- a/arch/powerpc/include/asm/device.h +++ b/arch/powerpc/include/asm/device.h @@ -48,6 +48,11 @@ struct dev_archdata { struct pdev_archdata { u64 dma_mask; + /* + * Pointer to nvdimm_pmu structure, to handle the unregistering + * of pmu device + */ + void *priv; }; #endif /* _ASM_POWERPC_DEVICE_H */ diff --git a/arch/powerpc/platforms/pseries/papr_scm.c b/arch/powerpc/platforms/pseries/papr_scm.c index f48e87a..4dd513d 100644 --- a/arch/powerpc/platforms/pseries/papr_scm.c +++ b/arch/powerpc/platforms/pseries/papr_scm.c @@ -19,6 +19,7 @@ #include #include #include +#include #define BIND_ANY_ADDR (~0ul) @@ -68,6 +69,8 @@ #define PAPR_SCM_PERF_STATS_EYECATCHER __stringify(SCMSTATS) #define PAPR_SCM_PERF_STATS_VERSION 0x1 +#define to_nvdimm_pmu(_pmu) container_of(_pmu, struct nvdimm_pmu, pmu) + /* Struct holding a single performance metric */ struct papr_scm_perf_stat { u8 stat_id[8]; @@ -120,6 +123,9 @@ struct papr_scm_priv { /* length of the stat buffer as expected by phyp */ size_t stat_buffer_len; + + /* array to have event_code and stat_id mappings */ + char **nvdimm_events_map; }; static int papr_scm_pmem_flush(struct nd_region *nd_region, @@ -340,6 +346,218 @@ static ssize_t drc_pmem_query_stats(struct papr_scm_priv *p, return 0; } +static int papr_scm_pmu_get_value(struct perf_event *event, struct device *dev, u64 *count) +{ + struct papr_scm_perf_stat *stat; + struct papr_scm_perf_stats *stats; + struct papr_scm_priv *p = (struct papr_scm_priv *)dev->driver_data; + int rc, size; + + /* Allocate request buffer enough to hold single performance stat */ + size = sizeof(struct papr_scm_perf_stats) + + sizeof(struct papr_scm_perf_stat); + + if (!p || !p->nvdimm_events_map) + return -EINVAL; + + stats = kzalloc(size, GFP_KERNEL); + if (!stats) + return -ENOMEM; + + stat = &stats->scm_statistic[0]; + memcpy(&stat->stat_id, + p->nvdimm_events_map[event->attr.config], + sizeof(stat->stat_id)); + stat->stat_val = 0; + + rc = drc_pmem_query_stats(p, stats, 1); + if (rc < 0) { + kfree(stats); + return rc; + } + + *count = be64_to_cpu(stat->stat_val); + kfree(stats); + return 0; +} + +static int papr_scm_pmu_event_init(struct perf_event *event) +{ + struct nvdimm_pmu *nd_pmu = to_nvdimm_pmu(event->pmu); + struct papr_scm_priv *p; + + if (!nd_pmu) + return -EINVAL; + + /* test the event attr type for PMU enumeration */ + if (event->attr.type != event->pmu->type) + return -ENOENT; + + /* it does not support event sampling mode */ + if (is_sampling_event(event)) + return -EOPNOTSUPP; + + /* no branch sampling */ + if (has_branch_stack(event)) + return -EOPNOTSUPP; + + p = (struct papr_scm_priv *)nd_pmu->dev->driver_data; + if (!p) + return -EINVAL; + + /* Invalid eventcode */ + if (event->attr.config == 0 || event->attr.config > 16) + return -EINVAL; + + return 0; +} + +static int papr_scm_pmu_add(struct perf_event *event, int flags) +{ + u64 count; + int rc; + struct nvdimm_pmu *nd_pmu = to_nvdimm_pmu(event->pmu); + + if (!nd_pmu) + return -EINVAL; + + if (flags & PERF_EF_START) { + rc = papr_scm_pmu_get_value(event, nd_pmu->dev, &count); + if (rc) + return rc; + + local64_set(&event->hw.prev_count, count); + } + + return 0; +} + +static void papr_scm_pmu_read(struct perf_event *event) +{ + u64 prev, now; + int rc; + struct nvdimm_pmu *nd_pmu = to_nvdimm_pmu(event->pmu); + + if (!nd_pmu) + return; + + rc = papr_scm_pmu_get_value(event, nd_pmu->dev, &now); + if (rc) + return; + + prev = local64_xchg(&event->hw.prev_count, now); + local64_add(now - prev, &event->count); +} + +static void papr_scm_pmu_del(struct perf_event *event, int flags) +{ + papr_scm_pmu_read(event); +} + +static int papr_scm_pmu_check_events(struct papr_scm_priv *p, struct nvdimm_pmu *nd_pmu) +{ + struct papr_scm_perf_stat *stat; + struct papr_scm_perf_stats *stats; + char *statid; + int index, rc, count; + u32 available_events; + + if (!p->stat_buffer_len) + return -ENOENT; + + available_events = (p->stat_buffer_len - sizeof(struct papr_scm_perf_stats)) + / sizeof(struct papr_scm_perf_stat); + + /* Allocate the buffer for phyp where stats are written */ + stats = kzalloc(p->stat_buffer_len, GFP_KERNEL); + if (!stats) { + rc = -ENOMEM; + return rc; + } + + /* Allocate memory to nvdimm_event_map */ + p->nvdimm_events_map = kcalloc(available_events, sizeof(char *), GFP_KERNEL); + if (!p->nvdimm_events_map) { + rc = -ENOMEM; + goto out_stats; + } + + /* Called to get list of events supported */ + rc = drc_pmem_query_stats(p, stats, 0); + if (rc) + goto out_nvdimm_events_map; + + for (index = 0, stat = stats->scm_statistic, count = 0; + index < available_events; index++, ++stat) { + statid = kzalloc(strlen(stat->stat_id) + 1, GFP_KERNEL); + if (!statid) { + rc = -ENOMEM; + goto out_nvdimm_events_map; + } + + strcpy(statid, stat->stat_id); + p->nvdimm_events_map[count] = statid; + count++; + } + p->nvdimm_events_map[count] = NULL; + kfree(stats); + return 0; + +out_nvdimm_events_map: + kfree(p->nvdimm_events_map); +out_stats: + kfree(stats); + return rc; +} + +static void papr_scm_pmu_register(struct papr_scm_priv *p) +{ + struct nvdimm_pmu *nd_pmu; + int rc, nodeid; + + nd_pmu = kzalloc(sizeof(*nd_pmu), GFP_KERNEL); + if (!nd_pmu) { + rc = -ENOMEM; + goto pmu_err_print; + } + + rc = papr_scm_pmu_check_events(p, nd_pmu); + if (rc) + goto pmu_check_events_err; + + nd_pmu->pmu.task_ctx_nr = perf_invalid_context; + nd_pmu->pmu.name = nvdimm_name(p->nvdimm); + nd_pmu->pmu.event_init = papr_scm_pmu_event_init; + nd_pmu->pmu.read = papr_scm_pmu_read; + nd_pmu->pmu.add = papr_scm_pmu_add; + nd_pmu->pmu.del = papr_scm_pmu_del; + + nd_pmu->pmu.capabilities = PERF_PMU_CAP_NO_INTERRUPT | + PERF_PMU_CAP_NO_EXCLUDE; + + /*updating the cpumask variable */ + nodeid = numa_map_to_online_node(dev_to_node(&p->pdev->dev)); + nd_pmu->arch_cpumask = *cpumask_of_node(nodeid); + + rc = register_nvdimm_pmu(nd_pmu, p->pdev); + if (rc) + goto pmu_register_err; + + /* + * Set archdata.priv value to nvdimm_pmu structure, to handle the + * unregistering of pmu device. + */ + p->pdev->archdata.priv = nd_pmu; + return; + +pmu_register_err: + kfree(p->nvdimm_events_map); +pmu_check_events_err: + kfree(nd_pmu); +pmu_err_print: + dev_info(&p->pdev->dev, "nvdimm pmu didn't register rc=%d\n", rc); +} + /* * Issue hcall to retrieve dimm health info and populate papr_scm_priv with the * health information. @@ -1236,6 +1454,7 @@ static int papr_scm_probe(struct platform_device *pdev) goto err2; platform_set_drvdata(pdev, p); + papr_scm_pmu_register(p); return 0; @@ -1254,6 +1473,12 @@ static int papr_scm_remove(struct platform_device *pdev) nvdimm_bus_unregister(p->bus); drc_pmem_unbind(p); + + if (pdev->archdata.priv) + unregister_nvdimm_pmu(pdev->archdata.priv); + + pdev->archdata.priv = NULL; + kfree(p->nvdimm_events_map); kfree(p->bus_desc.provider_name); kfree(p); -- 2.7.4