/* * In-Memory Collection (IMC) Performance Monitor counter support. * * Copyright (C) 2017 Madhavan Srinivasan, IBM Corporation. * (C) 2017 Anju T Sudhakar, IBM Corporation. * (C) 2017 Hemant K Shaw, IBM Corporation. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or later version. */ #include #include #include #include #include #include #include /* Nest IMC data structures and variables */ /* * Used to avoid races in counting the nest-pmu units during hotplug * register and unregister */ static DEFINE_MUTEX(nest_init_lock); static DEFINE_PER_CPU(struct imc_pmu_ref *, local_nest_imc_refc); static struct imc_pmu **per_nest_pmu_arr; static cpumask_t nest_imc_cpumask; struct imc_pmu_ref *nest_imc_refc; static int nest_pmus; /* Core IMC data structures and variables */ static cpumask_t core_imc_cpumask; struct imc_pmu_ref *core_imc_refc; static struct imc_pmu *core_imc_pmu; /* Thread IMC data structures and variables */ static DEFINE_PER_CPU(u64 *, thread_imc_mem); static int thread_imc_mem_size; struct imc_pmu *imc_event_to_pmu(struct perf_event *event) { return container_of(event->pmu, struct imc_pmu, pmu); } PMU_FORMAT_ATTR(event, "config:0-40"); PMU_FORMAT_ATTR(offset, "config:0-31"); PMU_FORMAT_ATTR(rvalue, "config:32"); PMU_FORMAT_ATTR(mode, "config:33-40"); static struct attribute *imc_format_attrs[] = { &format_attr_event.attr, &format_attr_offset.attr, &format_attr_rvalue.attr, &format_attr_mode.attr, NULL, }; static struct attribute_group imc_format_group = { .name = "format", .attrs = imc_format_attrs, }; /* Get the cpumask printed to a buffer "buf" */ static ssize_t imc_pmu_cpumask_get_attr(struct device *dev, struct device_attribute *attr, char *buf) { struct pmu *pmu = dev_get_drvdata(dev); struct imc_pmu *imc_pmu = container_of(pmu, struct imc_pmu, pmu); cpumask_t *active_mask; switch(imc_pmu->domain){ case IMC_DOMAIN_NEST: active_mask = &nest_imc_cpumask; break; case IMC_DOMAIN_CORE: active_mask = &core_imc_cpumask; break; default: return 0; } return cpumap_print_to_pagebuf(true, buf, active_mask); } static DEVICE_ATTR(cpumask, S_IRUGO, imc_pmu_cpumask_get_attr, NULL); static struct attribute *imc_pmu_cpumask_attrs[] = { &dev_attr_cpumask.attr, NULL, }; static struct attribute_group imc_pmu_cpumask_attr_group = { .attrs = imc_pmu_cpumask_attrs, }; /* device_str_attr_create : Populate event "name" and string "str" in attribute */ static struct attribute *device_str_attr_create(const char *name, const char *str) { struct perf_pmu_events_attr *attr; attr = kzalloc(sizeof(*attr), GFP_KERNEL); if (!attr) return NULL; sysfs_attr_init(&attr->attr.attr); attr->event_str = str; attr->attr.attr.name = name; attr->attr.attr.mode = 0444; attr->attr.show = perf_event_sysfs_show; return &attr->attr.attr; } static int imc_parse_event(struct device_node *np, const char *scale, const char *unit, const char *prefix, u32 base, struct imc_events *event) { const char *s; u32 reg; if (of_property_read_u32(np, "reg", ®)) goto error; /* Add the base_reg value to the "reg" */ event->value = base + reg; if (of_property_read_string(np, "event-name", &s)) goto error; event->name = kasprintf(GFP_KERNEL, "%s%s", prefix, s); if (!event->name) goto error; if (of_property_read_string(np, "scale", &s)) s = scale; if (s) { event->scale = kstrdup(s, GFP_KERNEL); if (!event->scale) goto error; } if (of_property_read_string(np, "unit", &s)) s = unit; if (s) { event->unit = kstrdup(s, GFP_KERNEL); if (!event->unit) goto error; } return 0; error: kfree(event->unit); kfree(event->scale); kfree(event->name); return -EINVAL; } /* * imc_free_events: Function to cleanup the events list, having * "nr_entries". */ static void imc_free_events(struct imc_events *events, int nr_entries) { int i; /* Nothing to clean, return */ if (!events) return; for (i = 0; i < nr_entries; i++) { kfree(events[i].unit); kfree(events[i].scale); kfree(events[i].name); } kfree(events); } /* * update_events_in_group: Update the "events" information in an attr_group * and assign the attr_group to the pmu "pmu". */ static int update_events_in_group(struct device_node *node, struct imc_pmu *pmu) { struct attribute_group *attr_group; struct attribute **attrs, *dev_str; struct device_node *np, *pmu_events; u32 handle, base_reg; int i = 0, j = 0, ct, ret; const char *prefix, *g_scale, *g_unit; const char *ev_val_str, *ev_scale_str, *ev_unit_str; if (!of_property_read_u32(node, "events", &handle)) pmu_events = of_find_node_by_phandle(handle); else return 0; /* Did not find any node with a given phandle */ if (!pmu_events) return 0; /* Get a count of number of child nodes */ ct = of_get_child_count(pmu_events); /* Get the event prefix */ if (of_property_read_string(node, "events-prefix", &prefix)) return 0; /* Get a global unit and scale data if available */ if (of_property_read_string(node, "scale", &g_scale)) g_scale = NULL; if (of_property_read_string(node, "unit", &g_unit)) g_unit = NULL; /* "reg" property gives out the base offset of the counters data */ of_property_read_u32(node, "reg", &base_reg); /* Allocate memory for the events */ pmu->events = kcalloc(ct, sizeof(struct imc_events), GFP_KERNEL); if (!pmu->events) return -ENOMEM; ct = 0; /* Parse the events and update the struct */ for_each_child_of_node(pmu_events, np) { ret = imc_parse_event(np, g_scale, g_unit, prefix, base_reg, &pmu->events[ct]); if (!ret) ct++; } /* Allocate memory for attribute group */ attr_group = kzalloc(sizeof(*attr_group), GFP_KERNEL); if (!attr_group) { imc_free_events(pmu->events, ct); return -ENOMEM; } /* * Allocate memory for attributes. * Since we have count of events for this pmu, we also allocate * memory for the scale and unit attribute for now. * "ct" has the total event structs added from the events-parent node. * So allocate three times the "ct" (this includes event, event_scale and * event_unit). */ attrs = kcalloc(((ct * 3) + 1), sizeof(struct attribute *), GFP_KERNEL); if (!attrs) { kfree(attr_group); imc_free_events(pmu->events, ct); return -ENOMEM; } attr_group->name = "events"; attr_group->attrs = attrs; do { ev_val_str = kasprintf(GFP_KERNEL, "event=0x%x", pmu->events[i].value); dev_str = device_str_attr_create(pmu->events[i].name, ev_val_str); if (!dev_str) continue; attrs[j++] = dev_str; if (pmu->events[i].scale) { ev_scale_str = kasprintf(GFP_KERNEL, "%s.scale", pmu->events[i].name); dev_str = device_str_attr_create(ev_scale_str, pmu->events[i].scale); if (!dev_str) continue; attrs[j++] = dev_str; } if (pmu->events[i].unit) { ev_unit_str = kasprintf(GFP_KERNEL, "%s.unit", pmu->events[i].name); dev_str = device_str_attr_create(ev_unit_str, pmu->events[i].unit); if (!dev_str) continue; attrs[j++] = dev_str; } } while (++i < ct); /* Save the event attribute */ pmu->attr_groups[IMC_EVENT_ATTR] = attr_group; return 0; } /* get_nest_pmu_ref: Return the imc_pmu_ref struct for the given node */ static struct imc_pmu_ref *get_nest_pmu_ref(int cpu) { return per_cpu(local_nest_imc_refc, cpu); } static void nest_change_cpu_context(int old_cpu, int new_cpu) { struct imc_pmu **pn = per_nest_pmu_arr; if (old_cpu < 0 || new_cpu < 0) return; while (*pn) { perf_pmu_migrate_context(&(*pn)->pmu, old_cpu, new_cpu); pn++; } } static int ppc_nest_imc_cpu_offline(unsigned int cpu) { int nid, target = -1; const struct cpumask *l_cpumask; struct imc_pmu_ref *ref; /* * Check in the designated list for this cpu. Dont bother * if not one of them. */ if (!cpumask_test_and_clear_cpu(cpu, &nest_imc_cpumask)) return 0; /* * Now that this cpu is one of the designated, * find a next cpu a) which is online and b) in same chip. */ nid = cpu_to_node(cpu); l_cpumask = cpumask_of_node(nid); target = cpumask_any_but(l_cpumask, cpu); /* * Update the cpumask with the target cpu and * migrate the context if needed */ if (target >= 0 && target < nr_cpu_ids) { cpumask_set_cpu(target, &nest_imc_cpumask); nest_change_cpu_context(cpu, target); } else { opal_imc_counters_stop(OPAL_IMC_COUNTERS_NEST, get_hard_smp_processor_id(cpu)); /* * If this is the last cpu in this chip then, skip the reference * count mutex lock and make the reference count on this chip zero. */ ref = get_nest_pmu_ref(cpu); if (!ref) return -EINVAL; ref->refc = 0; } return 0; } static int ppc_nest_imc_cpu_online(unsigned int cpu) { const struct cpumask *l_cpumask; static struct cpumask tmp_mask; int res; /* Get the cpumask of this node */ l_cpumask = cpumask_of_node(cpu_to_node(cpu)); /* * If this is not the first online CPU on this node, then * just return. */ if (cpumask_and(&tmp_mask, l_cpumask, &nest_imc_cpumask)) return 0; /* * If this is the first online cpu on this node * disable the nest counters by making an OPAL call. */ res = opal_imc_counters_stop(OPAL_IMC_COUNTERS_NEST, get_hard_smp_processor_id(cpu)); if (res) return res; /* Make this CPU the designated target for counter collection */ cpumask_set_cpu(cpu, &nest_imc_cpumask); return 0; } static int nest_pmu_cpumask_init(void) { return cpuhp_setup_state(CPUHP_AP_PERF_POWERPC_NEST_IMC_ONLINE, "perf/powerpc/imc:online", ppc_nest_imc_cpu_online, ppc_nest_imc_cpu_offline); } static void nest_imc_counters_release(struct perf_event *event) { int rc, node_id; struct imc_pmu_ref *ref; if (event->cpu < 0) return; node_id = cpu_to_node(event->cpu); /* * See if we need to disable the nest PMU. * If no events are currently in use, then we have to take a * mutex to ensure that we don't race with another task doing * enable or disable the nest counters. */ ref = get_nest_pmu_ref(event->cpu); if (!ref) return; /* Take the mutex lock for this node and then decrement the reference count */ mutex_lock(&ref->lock); if (ref->refc == 0) { /* * The scenario where this is true is, when perf session is * started, followed by offlining of all cpus in a given node. * * In the cpuhotplug offline path, ppc_nest_imc_cpu_offline() * function set the ref->count to zero, if the cpu which is * about to offline is the last cpu in a given node and make * an OPAL call to disable the engine in that node. * */ mutex_unlock(&ref->lock); return; } ref->refc--; if (ref->refc == 0) { rc = opal_imc_counters_stop(OPAL_IMC_COUNTERS_NEST, get_hard_smp_processor_id(event->cpu)); if (rc) { mutex_unlock(&ref->lock); pr_err("nest-imc: Unable to stop the counters for core %d\n", node_id); return; } } else if (ref->refc < 0) { WARN(1, "nest-imc: Invalid event reference count\n"); ref->refc = 0; } mutex_unlock(&ref->lock); } static int nest_imc_event_init(struct perf_event *event) { int chip_id, rc, node_id; u32 l_config, config = event->attr.config; struct imc_mem_info *pcni; struct imc_pmu *pmu; struct imc_pmu_ref *ref; bool flag = false; if (event->attr.type != event->pmu->type) return -ENOENT; /* Sampling not supported */ if (event->hw.sample_period) return -EINVAL; /* unsupported modes and filters */ if (event->attr.exclude_user || event->attr.exclude_kernel || event->attr.exclude_hv || event->attr.exclude_idle || event->attr.exclude_host || event->attr.exclude_guest) return -EINVAL; if (event->cpu < 0) return -EINVAL; pmu = imc_event_to_pmu(event); /* Sanity check for config (event offset) */ if ((config & IMC_EVENT_OFFSET_MASK) > pmu->counter_mem_size) return -EINVAL; /* * Nest HW counter memory resides in a per-chip reserve-memory (HOMER). * Get the base memory addresss for this cpu. */ chip_id = cpu_to_chip_id(event->cpu); pcni = pmu->mem_info; do { if (pcni->id == chip_id) { flag = true; break; } pcni++; } while (pcni); if (!flag) return -ENODEV; /* * Add the event offset to the base address. */ l_config = config & IMC_EVENT_OFFSET_MASK; event->hw.event_base = (u64)pcni->vbase + l_config; node_id = cpu_to_node(event->cpu); /* * Get the imc_pmu_ref struct for this node. * Take the mutex lock and then increment the count of nest pmu events * inited. */ ref = get_nest_pmu_ref(event->cpu); if (!ref) return -EINVAL; mutex_lock(&ref->lock); if (ref->refc == 0) { rc = opal_imc_counters_start(OPAL_IMC_COUNTERS_NEST, get_hard_smp_processor_id(event->cpu)); if (rc) { mutex_unlock(&ref->lock); pr_err("nest-imc: Unable to start the counters for node %d\n", node_id); return rc; } } ++ref->refc; mutex_unlock(&ref->lock); event->destroy = nest_imc_counters_release; return 0; } /* * core_imc_mem_init : Initializes memory for the current core. * * Uses alloc_pages_node() and uses the returned address as an argument to * an opal call to configure the pdbar. The address sent as an argument is * converted to physical address before the opal call is made. This is the * base address at which the core imc counters are populated. */ static int core_imc_mem_init(int cpu, int size) { int nid, rc = 0, core_id = (cpu / threads_per_core); struct imc_mem_info *mem_info; /* * alloc_pages_node() will allocate memory for core in the * local node only. */ nid = cpu_to_node(cpu); mem_info = &core_imc_pmu->mem_info[core_id]; mem_info->id = core_id; /* We need only vbase for core counters */ mem_info->vbase = page_address(alloc_pages_node(nid, GFP_KERNEL | __GFP_ZERO | __GFP_THISNODE | __GFP_NOWARN, get_order(size))); if (!mem_info->vbase) return -ENOMEM; /* Init the mutex */ core_imc_refc[core_id].id = core_id; mutex_init(&core_imc_refc[core_id].lock); rc = opal_imc_counters_init(OPAL_IMC_COUNTERS_CORE, __pa((void *)mem_info->vbase), get_hard_smp_processor_id(cpu)); if (rc) { free_pages((u64)mem_info->vbase, get_order(size)); mem_info->vbase = NULL; } return rc; } static bool is_core_imc_mem_inited(int cpu) { struct imc_mem_info *mem_info; int core_id = (cpu / threads_per_core); mem_info = &core_imc_pmu->mem_info[core_id]; if (!mem_info->vbase) return false; return true; } static int ppc_core_imc_cpu_online(unsigned int cpu) { const struct cpumask *l_cpumask; static struct cpumask tmp_mask; int ret = 0; /* Get the cpumask for this core */ l_cpumask = cpu_sibling_mask(cpu); /* If a cpu for this core is already set, then, don't do anything */ if (cpumask_and(&tmp_mask, l_cpumask, &core_imc_cpumask)) return 0; if (!is_core_imc_mem_inited(cpu)) { ret = core_imc_mem_init(cpu, core_imc_pmu->counter_mem_size); if (ret) { pr_info("core_imc memory allocation for cpu %d failed\n", cpu); return ret; } } /* set the cpu in the mask */ cpumask_set_cpu(cpu, &core_imc_cpumask); return 0; } static int ppc_core_imc_cpu_offline(unsigned int cpu) { unsigned int ncpu, core_id; struct imc_pmu_ref *ref; /* * clear this cpu out of the mask, if not present in the mask, * don't bother doing anything. */ if (!cpumask_test_and_clear_cpu(cpu, &core_imc_cpumask)) return 0; /* * Check whether core_imc is registered. We could end up here * if the cpuhotplug callback registration fails. i.e, callback * invokes the offline path for all sucessfully registered cpus. * At this stage, core_imc pmu will not be registered and we * should return here. * * We return with a zero since this is not an offline failure. * And cpuhp_setup_state() returns the actual failure reason * to the caller, which inturn will call the cleanup routine. */ if (!core_imc_pmu->pmu.event_init) return 0; /* Find any online cpu in that core except the current "cpu" */ ncpu = cpumask_any_but(cpu_sibling_mask(cpu), cpu); if (ncpu >= 0 && ncpu < nr_cpu_ids) { cpumask_set_cpu(ncpu, &core_imc_cpumask); perf_pmu_migrate_context(&core_imc_pmu->pmu, cpu, ncpu); } else { /* * If this is the last cpu in this core then, skip taking refernce * count mutex lock for this core and directly zero "refc" for * this core. */ opal_imc_counters_stop(OPAL_IMC_COUNTERS_CORE, get_hard_smp_processor_id(cpu)); core_id = cpu / threads_per_core; ref = &core_imc_refc[core_id]; if (!ref) return -EINVAL; ref->refc = 0; } return 0; } static int core_imc_pmu_cpumask_init(void) { return cpuhp_setup_state(CPUHP_AP_PERF_POWERPC_CORE_IMC_ONLINE, "perf/powerpc/imc_core:online", ppc_core_imc_cpu_online, ppc_core_imc_cpu_offline); } static void core_imc_counters_release(struct perf_event *event) { int rc, core_id; struct imc_pmu_ref *ref; if (event->cpu < 0) return; /* * See if we need to disable the IMC PMU. * If no events are currently in use, then we have to take a * mutex to ensure that we don't race with another task doing * enable or disable the core counters. */ core_id = event->cpu / threads_per_core; /* Take the mutex lock and decrement the refernce count for this core */ ref = &core_imc_refc[core_id]; if (!ref) return; mutex_lock(&ref->lock); if (ref->refc == 0) { /* * The scenario where this is true is, when perf session is * started, followed by offlining of all cpus in a given core. * * In the cpuhotplug offline path, ppc_core_imc_cpu_offline() * function set the ref->count to zero, if the cpu which is * about to offline is the last cpu in a given core and make * an OPAL call to disable the engine in that core. * */ mutex_unlock(&ref->lock); return; } ref->refc--; if (ref->refc == 0) { rc = opal_imc_counters_stop(OPAL_IMC_COUNTERS_CORE, get_hard_smp_processor_id(event->cpu)); if (rc) { mutex_unlock(&ref->lock); pr_err("IMC: Unable to stop the counters for core %d\n", core_id); return; } } else if (ref->refc < 0) { WARN(1, "core-imc: Invalid event reference count\n"); ref->refc = 0; } mutex_unlock(&ref->lock); } static int core_imc_event_init(struct perf_event *event) { int core_id, rc; u64 config = event->attr.config; struct imc_mem_info *pcmi; struct imc_pmu *pmu; struct imc_pmu_ref *ref; if (event->attr.type != event->pmu->type) return -ENOENT; /* Sampling not supported */ if (event->hw.sample_period) return -EINVAL; /* unsupported modes and filters */ if (event->attr.exclude_user || event->attr.exclude_kernel || event->attr.exclude_hv || event->attr.exclude_idle || event->attr.exclude_host || event->attr.exclude_guest) return -EINVAL; if (event->cpu < 0) return -EINVAL; event->hw.idx = -1; pmu = imc_event_to_pmu(event); /* Sanity check for config (event offset) */ if (((config & IMC_EVENT_OFFSET_MASK) > pmu->counter_mem_size)) return -EINVAL; if (!is_core_imc_mem_inited(event->cpu)) return -ENODEV; core_id = event->cpu / threads_per_core; pcmi = &core_imc_pmu->mem_info[core_id]; if ((!pcmi->vbase)) return -ENODEV; /* Get the core_imc mutex for this core */ ref = &core_imc_refc[core_id]; if (!ref) return -EINVAL; /* * Core pmu units are enabled only when it is used. * See if this is triggered for the first time. * If yes, take the mutex lock and enable the core counters. * If not, just increment the count in core_imc_refc struct. */ mutex_lock(&ref->lock); if (ref->refc == 0) { rc = opal_imc_counters_start(OPAL_IMC_COUNTERS_CORE, get_hard_smp_processor_id(event->cpu)); if (rc) { mutex_unlock(&ref->lock); pr_err("core-imc: Unable to start the counters for core %d\n", core_id); return rc; } } ++ref->refc; mutex_unlock(&ref->lock); event->hw.event_base = (u64)pcmi->vbase + (config & IMC_EVENT_OFFSET_MASK); event->destroy = core_imc_counters_release; return 0; } /* * Allocates a page of memory for each of the online cpus, and write the * physical base address of that page to the LDBAR for that cpu. * * LDBAR Register Layout: * * 0 4 8 12 16 20 24 28 * | - - - - | - - - - | - - - - | - - - - | - - - - | - - - - | - - - - | - - - - | * | | [ ] [ Counter Address [8:50] * | * Mode | * | * PB Scope * * Enable/Disable * * 32 36 40 44 48 52 56 60 * | - - - - | - - - - | - - - - | - - - - | - - - - | - - - - | - - - - | - - - - | * Counter Address [8:50] ] * */ static int thread_imc_mem_alloc(int cpu_id, int size) { u64 ldbar_value, *local_mem = per_cpu(thread_imc_mem, cpu_id); int nid = cpu_to_node(cpu_id); if (!local_mem) { /* * This case could happen only once at start, since we dont * free the memory in cpu offline path. */ local_mem = page_address(alloc_pages_node(nid, GFP_KERNEL | __GFP_ZERO | __GFP_THISNODE | __GFP_NOWARN, get_order(size))); if (!local_mem) return -ENOMEM; per_cpu(thread_imc_mem, cpu_id) = local_mem; } ldbar_value = ((u64)local_mem & THREAD_IMC_LDBAR_MASK) | THREAD_IMC_ENABLE; mtspr(SPRN_LDBAR, ldbar_value); return 0; } static int ppc_thread_imc_cpu_online(unsigned int cpu) { return thread_imc_mem_alloc(cpu, thread_imc_mem_size); } static int ppc_thread_imc_cpu_offline(unsigned int cpu) { mtspr(SPRN_LDBAR, 0); return 0; } static int thread_imc_cpu_init(void) { return cpuhp_setup_state(CPUHP_AP_PERF_POWERPC_THREAD_IMC_ONLINE, "perf/powerpc/imc_thread:online", ppc_thread_imc_cpu_online, ppc_thread_imc_cpu_offline); } void thread_imc_pmu_sched_task(struct perf_event_context *ctx, bool sched_in) { int core_id; struct imc_pmu_ref *ref; if (!is_core_imc_mem_inited(smp_processor_id())) return; core_id = smp_processor_id() / threads_per_core; /* * imc pmus are enabled only when it is used. * See if this is triggered for the first time. * If yes, take the mutex lock and enable the counters. * If not, just increment the count in ref count struct. */ ref = &core_imc_refc[core_id]; if (!ref) return; if (sched_in) { mutex_lock(&ref->lock); if (ref->refc == 0) { if (opal_imc_counters_start(OPAL_IMC_COUNTERS_CORE, get_hard_smp_processor_id(smp_processor_id()))) { mutex_unlock(&ref->lock); pr_err("thread-imc: Unable to start the counter\ for core %d\n", core_id); return; } } ++ref->refc; mutex_unlock(&ref->lock); } else { mutex_lock(&ref->lock); ref->refc--; if (ref->refc == 0) { if (opal_imc_counters_stop(OPAL_IMC_COUNTERS_CORE, get_hard_smp_processor_id(smp_processor_id()))) { mutex_unlock(&ref->lock); pr_err("thread-imc: Unable to stop the counters\ for core %d\n", core_id); return; } } else if (ref->refc < 0) { ref->refc = 0; } mutex_unlock(&ref->lock); } return; } static int thread_imc_event_init(struct perf_event *event) { u32 config = event->attr.config; struct task_struct *target; struct imc_pmu *pmu; if (event->attr.type != event->pmu->type) return -ENOENT; /* Sampling not supported */ if (event->hw.sample_period) return -EINVAL; event->hw.idx = -1; pmu = imc_event_to_pmu(event); /* Sanity check for config offset */ if (((config & IMC_EVENT_OFFSET_MASK) > pmu->counter_mem_size)) return -EINVAL; target = event->hw.target; if (!target) return -EINVAL; event->pmu->task_ctx_nr = perf_sw_context; return 0; } static bool is_thread_imc_pmu(struct perf_event *event) { if (!strncmp(event->pmu->name, "thread_imc", strlen("thread_imc"))) return true; return false; } static u64 * get_event_base_addr(struct perf_event *event) { u64 addr; if (is_thread_imc_pmu(event)) { addr = (u64)per_cpu(thread_imc_mem, smp_processor_id()); return (u64 *)(addr + (event->attr.config & IMC_EVENT_OFFSET_MASK)); } return (u64 *)event->hw.event_base; } static void thread_imc_pmu_start_txn(struct pmu *pmu, unsigned int txn_flags) { if (txn_flags & ~PERF_PMU_TXN_ADD) return; perf_pmu_disable(pmu); } static void thread_imc_pmu_cancel_txn(struct pmu *pmu) { perf_pmu_enable(pmu); } static int thread_imc_pmu_commit_txn(struct pmu *pmu) { perf_pmu_enable(pmu); return 0; } static u64 imc_read_counter(struct perf_event *event) { u64 *addr, data; /* * In-Memory Collection (IMC) counters are free flowing counters. * So we take a snapshot of the counter value on enable and save it * to calculate the delta at later stage to present the event counter * value. */ addr = get_event_base_addr(event); data = be64_to_cpu(READ_ONCE(*addr)); local64_set(&event->hw.prev_count, data); return data; } static void imc_event_update(struct perf_event *event) { u64 counter_prev, counter_new, final_count; counter_prev = local64_read(&event->hw.prev_count); counter_new = imc_read_counter(event); final_count = counter_new - counter_prev; /* Update the delta to the event count */ local64_add(final_count, &event->count); } static void imc_event_start(struct perf_event *event, int flags) { /* * In Memory Counters are free flowing counters. HW or the microcode * keeps adding to the counter offset in memory. To get event * counter value, we snapshot the value here and we calculate * delta at later point. */ imc_read_counter(event); } static void imc_event_stop(struct perf_event *event, int flags) { /* * Take a snapshot and calculate the delta and update * the event counter values. */ imc_event_update(event); } static int imc_event_add(struct perf_event *event, int flags) { if (flags & PERF_EF_START) imc_event_start(event, flags); return 0; } static int thread_imc_event_add(struct perf_event *event, int flags) { if (flags & PERF_EF_START) imc_event_start(event, flags); /* Enable the sched_task to start the engine */ perf_sched_cb_inc(event->ctx->pmu); return 0; } static void thread_imc_event_del(struct perf_event *event, int flags) { /* * Take a snapshot and calculate the delta and update * the event counter values. */ imc_event_update(event); perf_sched_cb_dec(event->ctx->pmu); } /* update_pmu_ops : Populate the appropriate operations for "pmu" */ static int update_pmu_ops(struct imc_pmu *pmu) { pmu->pmu.task_ctx_nr = perf_invalid_context; pmu->pmu.add = imc_event_add; pmu->pmu.del = imc_event_stop; pmu->pmu.start = imc_event_start; pmu->pmu.stop = imc_event_stop; pmu->pmu.read = imc_event_update; pmu->pmu.attr_groups = pmu->attr_groups; pmu->attr_groups[IMC_FORMAT_ATTR] = &imc_format_group; switch (pmu->domain) { case IMC_DOMAIN_NEST: pmu->pmu.event_init = nest_imc_event_init; pmu->attr_groups[IMC_CPUMASK_ATTR] = &imc_pmu_cpumask_attr_group; break; case IMC_DOMAIN_CORE: pmu->pmu.event_init = core_imc_event_init; pmu->attr_groups[IMC_CPUMASK_ATTR] = &imc_pmu_cpumask_attr_group; break; case IMC_DOMAIN_THREAD: pmu->pmu.event_init = thread_imc_event_init; pmu->pmu.sched_task = thread_imc_pmu_sched_task; pmu->pmu.add = thread_imc_event_add; pmu->pmu.del = thread_imc_event_del; pmu->pmu.start_txn = thread_imc_pmu_start_txn; pmu->pmu.cancel_txn = thread_imc_pmu_cancel_txn; pmu->pmu.commit_txn = thread_imc_pmu_commit_txn; break; default: break; } return 0; } /* init_nest_pmu_ref: Initialize the imc_pmu_ref struct for all the nodes */ static int init_nest_pmu_ref(void) { int nid, i, cpu; nest_imc_refc = kcalloc(num_possible_nodes(), sizeof(*nest_imc_refc), GFP_KERNEL); if (!nest_imc_refc) return -ENOMEM; i = 0; for_each_node(nid) { /* * Mutex lock to avoid races while tracking the number of * sessions using the chip's nest pmu units. */ mutex_init(&nest_imc_refc[i].lock); /* * Loop to init the "id" with the node_id. Variable "i" initialized to * 0 and will be used as index to the array. "i" will not go off the * end of the array since the "for_each_node" loops for "N_POSSIBLE" * nodes only. */ nest_imc_refc[i++].id = nid; } /* * Loop to init the per_cpu "local_nest_imc_refc" with the proper * "nest_imc_refc" index. This makes get_nest_pmu_ref() alot simple. */ for_each_possible_cpu(cpu) { nid = cpu_to_node(cpu); for (i = 0; i < num_possible_nodes(); i++) { if (nest_imc_refc[i].id == nid) { per_cpu(local_nest_imc_refc, cpu) = &nest_imc_refc[i]; break; } } } return 0; } static void cleanup_all_core_imc_memory(void) { int i, nr_cores = DIV_ROUND_UP(num_present_cpus(), threads_per_core); struct imc_mem_info *ptr = core_imc_pmu->mem_info; int size = core_imc_pmu->counter_mem_size; /* mem_info will never be NULL */ for (i = 0; i < nr_cores; i++) { if (ptr[i].vbase) free_pages((u64)ptr->vbase, get_order(size)); } kfree(ptr); kfree(core_imc_refc); } static void thread_imc_ldbar_disable(void *dummy) { /* * By Zeroing LDBAR, we disable thread-imc * updates. */ mtspr(SPRN_LDBAR, 0); } void thread_imc_disable(void) { on_each_cpu(thread_imc_ldbar_disable, NULL, 1); } static void cleanup_all_thread_imc_memory(void) { int i, order = get_order(thread_imc_mem_size); for_each_online_cpu(i) { if (per_cpu(thread_imc_mem, i)) free_pages((u64)per_cpu(thread_imc_mem, i), order); } } /* Function to free the attr_groups which are dynamically allocated */ static void imc_common_mem_free(struct imc_pmu *pmu_ptr) { if (pmu_ptr->attr_groups[IMC_EVENT_ATTR]) kfree(pmu_ptr->attr_groups[IMC_EVENT_ATTR]->attrs); kfree(pmu_ptr->attr_groups[IMC_EVENT_ATTR]); kfree(pmu_ptr); kfree(per_nest_pmu_arr); } /* * Common function to unregister cpu hotplug callback and * free the memory. * TODO: Need to handle pmu unregistering, which will be * done in followup series. */ static void imc_common_cpuhp_mem_free(struct imc_pmu *pmu_ptr) { if (pmu_ptr->domain == IMC_DOMAIN_NEST) { mutex_lock(&nest_init_lock); if (nest_pmus == 1) { cpuhp_remove_state(CPUHP_AP_PERF_POWERPC_NEST_IMC_ONLINE); kfree(nest_imc_refc); } if (nest_pmus > 0) nest_pmus--; mutex_unlock(&nest_init_lock); } /* Free core_imc memory */ if (pmu_ptr->domain == IMC_DOMAIN_CORE) { cpuhp_remove_state(CPUHP_AP_PERF_POWERPC_CORE_IMC_ONLINE); cleanup_all_core_imc_memory(); } /* Free thread_imc memory */ if (pmu_ptr->domain == IMC_DOMAIN_THREAD) { cpuhp_remove_state(CPUHP_AP_PERF_POWERPC_THREAD_IMC_ONLINE); cleanup_all_thread_imc_memory(); } } /* * imc_mem_init : Function to support memory allocation for core imc. */ static int imc_mem_init(struct imc_pmu *pmu_ptr, struct device_node *parent, int pmu_index) { const char *s; int nr_cores, cpu, res; if (of_property_read_string(parent, "name", &s)) return -ENODEV; switch (pmu_ptr->domain) { case IMC_DOMAIN_NEST: /* Update the pmu name */ pmu_ptr->pmu.name = kasprintf(GFP_KERNEL, "%s%s_imc", "nest_", s); if (!pmu_ptr->pmu.name) return -ENOMEM; /* Needed for hotplug/migration */ if (!per_nest_pmu_arr) { per_nest_pmu_arr = kcalloc(get_max_nest_dev() + 1, sizeof(struct imc_pmu *), GFP_KERNEL); if (!per_nest_pmu_arr) return -ENOMEM; } per_nest_pmu_arr[pmu_index] = pmu_ptr; break; case IMC_DOMAIN_CORE: /* Update the pmu name */ pmu_ptr->pmu.name = kasprintf(GFP_KERNEL, "%s%s", s, "_imc"); if (!pmu_ptr->pmu.name) return -ENOMEM; nr_cores = DIV_ROUND_UP(num_present_cpus(), threads_per_core); pmu_ptr->mem_info = kcalloc(nr_cores, sizeof(struct imc_mem_info), GFP_KERNEL); if (!pmu_ptr->mem_info) return -ENOMEM; core_imc_refc = kcalloc(nr_cores, sizeof(struct imc_pmu_ref), GFP_KERNEL); if (!core_imc_refc) { kfree(pmu_ptr->mem_info); return -ENOMEM; } core_imc_pmu = pmu_ptr; break; case IMC_DOMAIN_THREAD: /* Update the pmu name */ pmu_ptr->pmu.name = kasprintf(GFP_KERNEL, "%s%s", s, "_imc"); if (!pmu_ptr->pmu.name) return -ENOMEM; thread_imc_mem_size = pmu_ptr->counter_mem_size; for_each_online_cpu(cpu) { res = thread_imc_mem_alloc(cpu, pmu_ptr->counter_mem_size); if (res) { cleanup_all_thread_imc_memory(); return res; } } break; default: return -EINVAL; } return 0; } /* * init_imc_pmu : Setup and register the IMC pmu device. * * @parent: Device tree unit node * @pmu_ptr: memory allocated for this pmu * @pmu_idx: Count of nest pmc registered * * init_imc_pmu() setup pmu cpumask and registers for a cpu hotplug callback. * Handles failure cases and accordingly frees memory. */ int init_imc_pmu(struct device_node *parent, struct imc_pmu *pmu_ptr, int pmu_idx) { int ret; ret = imc_mem_init(pmu_ptr, parent, pmu_idx); if (ret) { imc_common_mem_free(pmu_ptr); return ret; } switch (pmu_ptr->domain) { case IMC_DOMAIN_NEST: /* * Nest imc pmu need only one cpu per chip, we initialize the * cpumask for the first nest imc pmu and use the same for the * rest. To handle the cpuhotplug callback unregister, we track * the number of nest pmus in "nest_pmus". */ mutex_lock(&nest_init_lock); if (nest_pmus == 0) { ret = init_nest_pmu_ref(); if (ret) { mutex_unlock(&nest_init_lock); goto err_free; } /* Register for cpu hotplug notification. */ ret = nest_pmu_cpumask_init(); if (ret) { mutex_unlock(&nest_init_lock); goto err_free; } } nest_pmus++; mutex_unlock(&nest_init_lock); break; case IMC_DOMAIN_CORE: ret = core_imc_pmu_cpumask_init(); if (ret) { cleanup_all_core_imc_memory(); return ret; } break; case IMC_DOMAIN_THREAD: ret = thread_imc_cpu_init(); if (ret) { cleanup_all_thread_imc_memory(); return ret; } break; default: return -1; /* Unknown domain */ } ret = update_events_in_group(parent, pmu_ptr); if (ret) goto err_free; ret = update_pmu_ops(pmu_ptr); if (ret) goto err_free; ret = perf_pmu_register(&pmu_ptr->pmu, pmu_ptr->pmu.name, -1); if (ret) goto err_free; pr_info("%s performance monitor hardware support registered\n", pmu_ptr->pmu.name); return 0; err_free: imc_common_mem_free(pmu_ptr); imc_common_cpuhp_mem_free(pmu_ptr); return ret; }