| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Thomas Richter | 5971 | 90.33% | 8 | 34.78% |
| Hendrik Brueckner | 588 | 8.90% | 10 | 43.48% |
| Heiko Carstens | 40 | 0.61% | 1 | 4.35% |
| Vasily Gorbik | 6 | 0.09% | 1 | 4.35% |
| Sebastian Andrzej Siewior | 2 | 0.03% | 1 | 4.35% |
| Christoph Lameter | 2 | 0.03% | 1 | 4.35% |
| Greg Kroah-Hartman | 1 | 0.02% | 1 | 4.35% |
| Total | 6610 | 23 |
// SPDX-License-Identifier: GPL-2.0 /* * Performance event support for s390x - CPU-measurement Counter Facility * * Copyright IBM Corp. 2012, 2021 * Author(s): Hendrik Brueckner <brueckner@linux.ibm.com> * Thomas Richter <tmricht@linux.ibm.com> */ #define KMSG_COMPONENT "cpum_cf" #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt #include <linux/kernel.h> #include <linux/kernel_stat.h> #include <linux/percpu.h> #include <linux/notifier.h> #include <linux/init.h> #include <linux/export.h> #include <linux/miscdevice.h> #include <asm/cpu_mcf.h> #include <asm/hwctrset.h> #include <asm/debug.h> static unsigned int cfdiag_cpu_speed; /* CPU speed for CF_DIAG trailer */ static debug_info_t *cf_dbg; #define CF_DIAG_CTRSET_DEF 0xfeef /* Counter set header mark */ /* interval in seconds */ /* Counter sets are stored as data stream in a page sized memory buffer and * exported to user space via raw data attached to the event sample data. * Each counter set starts with an eight byte header consisting of: * - a two byte eye catcher (0xfeef) * - a one byte counter set number * - a two byte counter set size (indicates the number of counters in this set) * - a three byte reserved value (must be zero) to make the header the same * size as a counter value. * All counter values are eight byte in size. * * All counter sets are followed by a 64 byte trailer. * The trailer consists of a: * - flag field indicating valid fields when corresponding bit set * - the counter facility first and second version number * - the CPU speed if nonzero * - the time stamp the counter sets have been collected * - the time of day (TOD) base value * - the machine type. * * The counter sets are saved when the process is prepared to be executed on a * CPU and saved again when the process is going to be removed from a CPU. * The difference of both counter sets are calculated and stored in the event * sample data area. */ struct cf_ctrset_entry { /* CPU-M CF counter set entry (8 byte) */ unsigned int def:16; /* 0-15 Data Entry Format */ unsigned int set:16; /* 16-31 Counter set identifier */ unsigned int ctr:16; /* 32-47 Number of stored counters */ unsigned int res1:16; /* 48-63 Reserved */ }; struct cf_trailer_entry { /* CPU-M CF_DIAG trailer (64 byte) */ /* 0 - 7 */ union { struct { unsigned int clock_base:1; /* TOD clock base set */ unsigned int speed:1; /* CPU speed set */ /* Measurement alerts */ unsigned int mtda:1; /* Loss of MT ctr. data alert */ unsigned int caca:1; /* Counter auth. change alert */ unsigned int lcda:1; /* Loss of counter data alert */ }; unsigned long flags; /* 0-63 All indicators */ }; /* 8 - 15 */ unsigned int cfvn:16; /* 64-79 Ctr First Version */ unsigned int csvn:16; /* 80-95 Ctr Second Version */ unsigned int cpu_speed:32; /* 96-127 CPU speed */ /* 16 - 23 */ unsigned long timestamp; /* 128-191 Timestamp (TOD) */ /* 24 - 55 */ union { struct { unsigned long progusage1; unsigned long progusage2; unsigned long progusage3; unsigned long tod_base; }; unsigned long progusage[4]; }; /* 56 - 63 */ unsigned int mach_type:16; /* Machine type */ unsigned int res1:16; /* Reserved */ unsigned int res2:32; /* Reserved */ }; /* Create the trailer data at the end of a page. */ static void cfdiag_trailer(struct cf_trailer_entry *te) { struct cpu_cf_events *cpuhw = this_cpu_ptr(&cpu_cf_events); struct cpuid cpuid; te->cfvn = cpuhw->info.cfvn; /* Counter version numbers */ te->csvn = cpuhw->info.csvn; get_cpu_id(&cpuid); /* Machine type */ te->mach_type = cpuid.machine; te->cpu_speed = cfdiag_cpu_speed; if (te->cpu_speed) te->speed = 1; te->clock_base = 1; /* Save clock base */ te->tod_base = tod_clock_base.tod; te->timestamp = get_tod_clock_fast(); } /* Read a counter set. The counter set number determines the counter set and * the CPUM-CF first and second version number determine the number of * available counters in each counter set. * Each counter set starts with header containing the counter set number and * the number of eight byte counters. * * The functions returns the number of bytes occupied by this counter set * including the header. * If there is no counter in the counter set, this counter set is useless and * zero is returned on this case. * * Note that the counter sets may not be enabled or active and the stcctm * instruction might return error 3. Depending on error_ok value this is ok, * for example when called from cpumf_pmu_start() call back function. */ static size_t cfdiag_getctrset(struct cf_ctrset_entry *ctrdata, int ctrset, size_t room, bool error_ok) { struct cpu_cf_events *cpuhw = this_cpu_ptr(&cpu_cf_events); size_t ctrset_size, need = 0; int rc = 3; /* Assume write failure */ ctrdata->def = CF_DIAG_CTRSET_DEF; ctrdata->set = ctrset; ctrdata->res1 = 0; ctrset_size = cpum_cf_ctrset_size(ctrset, &cpuhw->info); if (ctrset_size) { /* Save data */ need = ctrset_size * sizeof(u64) + sizeof(*ctrdata); if (need <= room) { rc = ctr_stcctm(ctrset, ctrset_size, (u64 *)(ctrdata + 1)); } if (rc != 3 || error_ok) ctrdata->ctr = ctrset_size; else need = 0; } debug_sprintf_event(cf_dbg, 3, "%s ctrset %d ctrset_size %zu cfvn %d csvn %d" " need %zd rc %d\n", __func__, ctrset, ctrset_size, cpuhw->info.cfvn, cpuhw->info.csvn, need, rc); return need; } static const u64 cpumf_ctr_ctl[CPUMF_CTR_SET_MAX] = { [CPUMF_CTR_SET_BASIC] = 0x02, [CPUMF_CTR_SET_USER] = 0x04, [CPUMF_CTR_SET_CRYPTO] = 0x08, [CPUMF_CTR_SET_EXT] = 0x01, [CPUMF_CTR_SET_MT_DIAG] = 0x20, }; /* Read out all counter sets and save them in the provided data buffer. * The last 64 byte host an artificial trailer entry. */ static size_t cfdiag_getctr(void *data, size_t sz, unsigned long auth, bool error_ok) { struct cf_trailer_entry *trailer; size_t offset = 0, done; int i; memset(data, 0, sz); sz -= sizeof(*trailer); /* Always room for trailer */ for (i = CPUMF_CTR_SET_BASIC; i < CPUMF_CTR_SET_MAX; ++i) { struct cf_ctrset_entry *ctrdata = data + offset; if (!(auth & cpumf_ctr_ctl[i])) continue; /* Counter set not authorized */ done = cfdiag_getctrset(ctrdata, i, sz - offset, error_ok); offset += done; } trailer = data + offset; cfdiag_trailer(trailer); return offset + sizeof(*trailer); } /* Calculate the difference for each counter in a counter set. */ static void cfdiag_diffctrset(u64 *pstart, u64 *pstop, int counters) { for (; --counters >= 0; ++pstart, ++pstop) if (*pstop >= *pstart) *pstop -= *pstart; else *pstop = *pstart - *pstop + 1; } /* Scan the counter sets and calculate the difference of each counter * in each set. The result is the increment of each counter during the * period the counter set has been activated. * * Return true on success. */ static int cfdiag_diffctr(struct cpu_cf_events *cpuhw, unsigned long auth) { struct cf_trailer_entry *trailer_start, *trailer_stop; struct cf_ctrset_entry *ctrstart, *ctrstop; size_t offset = 0; auth &= (1 << CPUMF_LCCTL_ENABLE_SHIFT) - 1; do { ctrstart = (struct cf_ctrset_entry *)(cpuhw->start + offset); ctrstop = (struct cf_ctrset_entry *)(cpuhw->stop + offset); if (memcmp(ctrstop, ctrstart, sizeof(*ctrstop))) { pr_err_once("cpum_cf_diag counter set compare error " "in set %i\n", ctrstart->set); return 0; } auth &= ~cpumf_ctr_ctl[ctrstart->set]; if (ctrstart->def == CF_DIAG_CTRSET_DEF) { cfdiag_diffctrset((u64 *)(ctrstart + 1), (u64 *)(ctrstop + 1), ctrstart->ctr); offset += ctrstart->ctr * sizeof(u64) + sizeof(*ctrstart); } } while (ctrstart->def && auth); /* Save time_stamp from start of event in stop's trailer */ trailer_start = (struct cf_trailer_entry *)(cpuhw->start + offset); trailer_stop = (struct cf_trailer_entry *)(cpuhw->stop + offset); trailer_stop->progusage[0] = trailer_start->timestamp; return 1; } static enum cpumf_ctr_set get_counter_set(u64 event) { int set = CPUMF_CTR_SET_MAX; if (event < 32) set = CPUMF_CTR_SET_BASIC; else if (event < 64) set = CPUMF_CTR_SET_USER; else if (event < 128) set = CPUMF_CTR_SET_CRYPTO; else if (event < 288) set = CPUMF_CTR_SET_EXT; else if (event >= 448 && event < 496) set = CPUMF_CTR_SET_MT_DIAG; return set; } static int validate_ctr_version(const struct hw_perf_event *hwc, enum cpumf_ctr_set set) { struct cpu_cf_events *cpuhw; int err = 0; u16 mtdiag_ctl; cpuhw = &get_cpu_var(cpu_cf_events); /* check required version for counter sets */ switch (set) { case CPUMF_CTR_SET_BASIC: case CPUMF_CTR_SET_USER: if (cpuhw->info.cfvn < 1) err = -EOPNOTSUPP; break; case CPUMF_CTR_SET_CRYPTO: if ((cpuhw->info.csvn >= 1 && cpuhw->info.csvn <= 5 && hwc->config > 79) || (cpuhw->info.csvn >= 6 && hwc->config > 83)) err = -EOPNOTSUPP; break; case CPUMF_CTR_SET_EXT: if (cpuhw->info.csvn < 1) err = -EOPNOTSUPP; if ((cpuhw->info.csvn == 1 && hwc->config > 159) || (cpuhw->info.csvn == 2 && hwc->config > 175) || (cpuhw->info.csvn >= 3 && cpuhw->info.csvn <= 5 && hwc->config > 255) || (cpuhw->info.csvn >= 6 && hwc->config > 287)) err = -EOPNOTSUPP; break; case CPUMF_CTR_SET_MT_DIAG: if (cpuhw->info.csvn <= 3) err = -EOPNOTSUPP; /* * MT-diagnostic counters are read-only. The counter set * is automatically enabled and activated on all CPUs with * multithreading (SMT). Deactivation of multithreading * also disables the counter set. State changes are ignored * by lcctl(). Because Linux controls SMT enablement through * a kernel parameter only, the counter set is either disabled * or enabled and active. * * Thus, the counters can only be used if SMT is on and the * counter set is enabled and active. */ mtdiag_ctl = cpumf_ctr_ctl[CPUMF_CTR_SET_MT_DIAG]; if (!((cpuhw->info.auth_ctl & mtdiag_ctl) && (cpuhw->info.enable_ctl & mtdiag_ctl) && (cpuhw->info.act_ctl & mtdiag_ctl))) err = -EOPNOTSUPP; break; case CPUMF_CTR_SET_MAX: err = -EOPNOTSUPP; } put_cpu_var(cpu_cf_events); return err; } static int validate_ctr_auth(const struct hw_perf_event *hwc) { struct cpu_cf_events *cpuhw; int err = 0; cpuhw = &get_cpu_var(cpu_cf_events); /* Check authorization for cpu counter sets. * If the particular CPU counter set is not authorized, * return with -ENOENT in order to fall back to other * PMUs that might suffice the event request. */ if (!(hwc->config_base & cpuhw->info.auth_ctl)) err = -ENOENT; put_cpu_var(cpu_cf_events); return err; } /* * Change the CPUMF state to active. * Enable and activate the CPU-counter sets according * to the per-cpu control state. */ static void cpumf_pmu_enable(struct pmu *pmu) { struct cpu_cf_events *cpuhw = this_cpu_ptr(&cpu_cf_events); int err; if (cpuhw->flags & PMU_F_ENABLED) return; err = lcctl(cpuhw->state | cpuhw->dev_state); if (err) { pr_err("Enabling the performance measuring unit " "failed with rc=%x\n", err); return; } cpuhw->flags |= PMU_F_ENABLED; } /* * Change the CPUMF state to inactive. * Disable and enable (inactive) the CPU-counter sets according * to the per-cpu control state. */ static void cpumf_pmu_disable(struct pmu *pmu) { struct cpu_cf_events *cpuhw = this_cpu_ptr(&cpu_cf_events); int err; u64 inactive; if (!(cpuhw->flags & PMU_F_ENABLED)) return; inactive = cpuhw->state & ~((1 << CPUMF_LCCTL_ENABLE_SHIFT) - 1); inactive |= cpuhw->dev_state; err = lcctl(inactive); if (err) { pr_err("Disabling the performance measuring unit " "failed with rc=%x\n", err); return; } cpuhw->flags &= ~PMU_F_ENABLED; } /* Number of perf events counting hardware events */ static atomic_t num_events = ATOMIC_INIT(0); /* Used to avoid races in calling reserve/release_cpumf_hardware */ static DEFINE_MUTEX(pmc_reserve_mutex); /* Release the PMU if event is the last perf event */ static void hw_perf_event_destroy(struct perf_event *event) { if (!atomic_add_unless(&num_events, -1, 1)) { mutex_lock(&pmc_reserve_mutex); if (atomic_dec_return(&num_events) == 0) __kernel_cpumcf_end(); mutex_unlock(&pmc_reserve_mutex); } } /* CPUMF <-> perf event mappings for kernel+userspace (basic set) */ static const int cpumf_generic_events_basic[] = { [PERF_COUNT_HW_CPU_CYCLES] = 0, [PERF_COUNT_HW_INSTRUCTIONS] = 1, [PERF_COUNT_HW_CACHE_REFERENCES] = -1, [PERF_COUNT_HW_CACHE_MISSES] = -1, [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = -1, [PERF_COUNT_HW_BRANCH_MISSES] = -1, [PERF_COUNT_HW_BUS_CYCLES] = -1, }; /* CPUMF <-> perf event mappings for userspace (problem-state set) */ static const int cpumf_generic_events_user[] = { [PERF_COUNT_HW_CPU_CYCLES] = 32, [PERF_COUNT_HW_INSTRUCTIONS] = 33, [PERF_COUNT_HW_CACHE_REFERENCES] = -1, [PERF_COUNT_HW_CACHE_MISSES] = -1, [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = -1, [PERF_COUNT_HW_BRANCH_MISSES] = -1, [PERF_COUNT_HW_BUS_CYCLES] = -1, }; static void cpumf_hw_inuse(void) { mutex_lock(&pmc_reserve_mutex); if (atomic_inc_return(&num_events) == 1) __kernel_cpumcf_begin(); mutex_unlock(&pmc_reserve_mutex); } static int __hw_perf_event_init(struct perf_event *event, unsigned int type) { struct perf_event_attr *attr = &event->attr; struct hw_perf_event *hwc = &event->hw; enum cpumf_ctr_set set; int err = 0; u64 ev; switch (type) { case PERF_TYPE_RAW: /* Raw events are used to access counters directly, * hence do not permit excludes */ if (attr->exclude_kernel || attr->exclude_user || attr->exclude_hv) return -EOPNOTSUPP; ev = attr->config; break; case PERF_TYPE_HARDWARE: if (is_sampling_event(event)) /* No sampling support */ return -ENOENT; ev = attr->config; /* Count user space (problem-state) only */ if (!attr->exclude_user && attr->exclude_kernel) { if (ev >= ARRAY_SIZE(cpumf_generic_events_user)) return -EOPNOTSUPP; ev = cpumf_generic_events_user[ev]; /* No support for kernel space counters only */ } else if (!attr->exclude_kernel && attr->exclude_user) { return -EOPNOTSUPP; } else { /* Count user and kernel space */ if (ev >= ARRAY_SIZE(cpumf_generic_events_basic)) return -EOPNOTSUPP; ev = cpumf_generic_events_basic[ev]; } break; default: return -ENOENT; } if (ev == -1) return -ENOENT; if (ev > PERF_CPUM_CF_MAX_CTR) return -ENOENT; /* Obtain the counter set to which the specified counter belongs */ set = get_counter_set(ev); switch (set) { case CPUMF_CTR_SET_BASIC: case CPUMF_CTR_SET_USER: case CPUMF_CTR_SET_CRYPTO: case CPUMF_CTR_SET_EXT: case CPUMF_CTR_SET_MT_DIAG: /* * Use the hardware perf event structure to store the * counter number in the 'config' member and the counter * set number in the 'config_base' as bit mask. * It is later used to enable/disable the counter(s). */ hwc->config = ev; hwc->config_base = cpumf_ctr_ctl[set]; break; case CPUMF_CTR_SET_MAX: /* The counter could not be associated to a counter set */ return -EINVAL; } /* Initialize for using the CPU-measurement counter facility */ cpumf_hw_inuse(); event->destroy = hw_perf_event_destroy; /* Finally, validate version and authorization of the counter set */ err = validate_ctr_auth(hwc); if (!err) err = validate_ctr_version(hwc, set); return err; } /* Events CPU_CYLCES and INSTRUCTIONS can be submitted with two different * attribute::type values: * - PERF_TYPE_HARDWARE: * - pmu->type: * Handle both type of invocations identical. They address the same hardware. * The result is different when event modifiers exclude_kernel and/or * exclude_user are also set. */ static int cpumf_pmu_event_type(struct perf_event *event) { u64 ev = event->attr.config; if (cpumf_generic_events_basic[PERF_COUNT_HW_CPU_CYCLES] == ev || cpumf_generic_events_basic[PERF_COUNT_HW_INSTRUCTIONS] == ev || cpumf_generic_events_user[PERF_COUNT_HW_CPU_CYCLES] == ev || cpumf_generic_events_user[PERF_COUNT_HW_INSTRUCTIONS] == ev) return PERF_TYPE_HARDWARE; return PERF_TYPE_RAW; } static int cpumf_pmu_event_init(struct perf_event *event) { unsigned int type = event->attr.type; int err; if (type == PERF_TYPE_HARDWARE || type == PERF_TYPE_RAW) err = __hw_perf_event_init(event, type); else if (event->pmu->type == type) /* Registered as unknown PMU */ err = __hw_perf_event_init(event, cpumf_pmu_event_type(event)); else return -ENOENT; if (unlikely(err) && event->destroy) event->destroy(event); return err; } static int hw_perf_event_reset(struct perf_event *event) { u64 prev, new; int err; do { prev = local64_read(&event->hw.prev_count); err = ecctr(event->hw.config, &new); if (err) { if (err != 3) break; /* The counter is not (yet) available. This * might happen if the counter set to which * this counter belongs is in the disabled * state. */ new = 0; } } while (local64_cmpxchg(&event->hw.prev_count, prev, new) != prev); return err; } static void hw_perf_event_update(struct perf_event *event) { u64 prev, new, delta; int err; do { prev = local64_read(&event->hw.prev_count); err = ecctr(event->hw.config, &new); if (err) return; } while (local64_cmpxchg(&event->hw.prev_count, prev, new) != prev); delta = (prev <= new) ? new - prev : (-1ULL - prev) + new + 1; /* overflow */ local64_add(delta, &event->count); } static void cpumf_pmu_read(struct perf_event *event) { if (event->hw.state & PERF_HES_STOPPED) return; hw_perf_event_update(event); } static void cpumf_pmu_start(struct perf_event *event, int flags) { struct cpu_cf_events *cpuhw = this_cpu_ptr(&cpu_cf_events); struct hw_perf_event *hwc = &event->hw; int i; if (!(hwc->state & PERF_HES_STOPPED)) return; hwc->state = 0; /* (Re-)enable and activate the counter set */ ctr_set_enable(&cpuhw->state, hwc->config_base); ctr_set_start(&cpuhw->state, hwc->config_base); /* The counter set to which this counter belongs can be already active. * Because all counters in a set are active, the event->hw.prev_count * needs to be synchronized. At this point, the counter set can be in * the inactive or disabled state. */ if (hwc->config == PERF_EVENT_CPUM_CF_DIAG) { cpuhw->usedss = cfdiag_getctr(cpuhw->start, sizeof(cpuhw->start), hwc->config_base, true); } else { hw_perf_event_reset(event); } /* Increment refcount for counter sets */ for (i = CPUMF_CTR_SET_BASIC; i < CPUMF_CTR_SET_MAX; ++i) if ((hwc->config_base & cpumf_ctr_ctl[i])) atomic_inc(&cpuhw->ctr_set[i]); } /* Create perf event sample with the counter sets as raw data. The sample * is then pushed to the event subsystem and the function checks for * possible event overflows. If an event overflow occurs, the PMU is * stopped. * * Return non-zero if an event overflow occurred. */ static int cfdiag_push_sample(struct perf_event *event, struct cpu_cf_events *cpuhw) { struct perf_sample_data data; struct perf_raw_record raw; struct pt_regs regs; int overflow; /* Setup perf sample */ perf_sample_data_init(&data, 0, event->hw.last_period); memset(®s, 0, sizeof(regs)); memset(&raw, 0, sizeof(raw)); if (event->attr.sample_type & PERF_SAMPLE_CPU) data.cpu_entry.cpu = event->cpu; if (event->attr.sample_type & PERF_SAMPLE_RAW) { raw.frag.size = cpuhw->usedss; raw.frag.data = cpuhw->stop; raw.size = raw.frag.size; data.raw = &raw; } overflow = perf_event_overflow(event, &data, ®s); debug_sprintf_event(cf_dbg, 3, "%s event %#llx sample_type %#llx raw %d ov %d\n", __func__, event->hw.config, event->attr.sample_type, raw.size, overflow); if (overflow) event->pmu->stop(event, 0); perf_event_update_userpage(event); return overflow; } static void cpumf_pmu_stop(struct perf_event *event, int flags) { struct cpu_cf_events *cpuhw = this_cpu_ptr(&cpu_cf_events); struct hw_perf_event *hwc = &event->hw; int i; if (!(hwc->state & PERF_HES_STOPPED)) { /* Decrement reference count for this counter set and if this * is the last used counter in the set, clear activation * control and set the counter set state to inactive. */ for (i = CPUMF_CTR_SET_BASIC; i < CPUMF_CTR_SET_MAX; ++i) { if (!(hwc->config_base & cpumf_ctr_ctl[i])) continue; if (!atomic_dec_return(&cpuhw->ctr_set[i])) ctr_set_stop(&cpuhw->state, cpumf_ctr_ctl[i]); } hwc->state |= PERF_HES_STOPPED; } if ((flags & PERF_EF_UPDATE) && !(hwc->state & PERF_HES_UPTODATE)) { if (hwc->config == PERF_EVENT_CPUM_CF_DIAG) { local64_inc(&event->count); cpuhw->usedss = cfdiag_getctr(cpuhw->stop, sizeof(cpuhw->stop), event->hw.config_base, false); if (cfdiag_diffctr(cpuhw, event->hw.config_base)) cfdiag_push_sample(event, cpuhw); } else if (cpuhw->flags & PMU_F_RESERVED) { /* Only update when PMU not hotplugged off */ hw_perf_event_update(event); } hwc->state |= PERF_HES_UPTODATE; } } static int cpumf_pmu_add(struct perf_event *event, int flags) { struct cpu_cf_events *cpuhw = this_cpu_ptr(&cpu_cf_events); ctr_set_enable(&cpuhw->state, event->hw.config_base); event->hw.state = PERF_HES_UPTODATE | PERF_HES_STOPPED; if (flags & PERF_EF_START) cpumf_pmu_start(event, PERF_EF_RELOAD); return 0; } static void cpumf_pmu_del(struct perf_event *event, int flags) { struct cpu_cf_events *cpuhw = this_cpu_ptr(&cpu_cf_events); int i; cpumf_pmu_stop(event, PERF_EF_UPDATE); /* Check if any counter in the counter set is still used. If not used, * change the counter set to the disabled state. This also clears the * content of all counters in the set. * * When a new perf event has been added but not yet started, this can * clear enable control and resets all counters in a set. Therefore, * cpumf_pmu_start() always has to reenable a counter set. */ for (i = CPUMF_CTR_SET_BASIC; i < CPUMF_CTR_SET_MAX; ++i) if (!atomic_read(&cpuhw->ctr_set[i])) ctr_set_disable(&cpuhw->state, cpumf_ctr_ctl[i]); } /* Performance monitoring unit for s390x */ static struct pmu cpumf_pmu = { .task_ctx_nr = perf_sw_context, .capabilities = PERF_PMU_CAP_NO_INTERRUPT, .pmu_enable = cpumf_pmu_enable, .pmu_disable = cpumf_pmu_disable, .event_init = cpumf_pmu_event_init, .add = cpumf_pmu_add, .del = cpumf_pmu_del, .start = cpumf_pmu_start, .stop = cpumf_pmu_stop, .read = cpumf_pmu_read, }; static int cfset_init(void); static int __init cpumf_pmu_init(void) { int rc; if (!kernel_cpumcf_avail()) return -ENODEV; /* Setup s390dbf facility */ cf_dbg = debug_register(KMSG_COMPONENT, 2, 1, 128); if (!cf_dbg) { pr_err("Registration of s390dbf(cpum_cf) failed\n"); return -ENOMEM; } debug_register_view(cf_dbg, &debug_sprintf_view); cpumf_pmu.attr_groups = cpumf_cf_event_group(); rc = perf_pmu_register(&cpumf_pmu, "cpum_cf", -1); if (rc) { debug_unregister_view(cf_dbg, &debug_sprintf_view); debug_unregister(cf_dbg); pr_err("Registering the cpum_cf PMU failed with rc=%i\n", rc); } else if (stccm_avail()) { /* Setup counter set device */ cfset_init(); } return rc; } /* Support for the CPU Measurement Facility counter set extraction using * device /dev/hwctr. This allows user space programs to extract complete * counter set via normal file operations. */ static atomic_t cfset_opencnt = ATOMIC_INIT(0); /* Access count */ static DEFINE_MUTEX(cfset_ctrset_mutex);/* Synchronize access to hardware */ struct cfset_call_on_cpu_parm { /* Parm struct for smp_call_on_cpu */ unsigned int sets; /* Counter set bit mask */ atomic_t cpus_ack; /* # CPUs successfully executed func */ }; static struct cfset_session { /* CPUs and counter set bit mask */ struct list_head head; /* Head of list of active processes */ } cfset_session = { .head = LIST_HEAD_INIT(cfset_session.head) }; struct cfset_request { /* CPUs and counter set bit mask */ unsigned long ctrset; /* Bit mask of counter set to read */ cpumask_t mask; /* CPU mask to read from */ struct list_head node; /* Chain to cfset_session.head */ }; static void cfset_session_init(void) { INIT_LIST_HEAD(&cfset_session.head); } /* Remove current request from global bookkeeping. Maintain a counter set bit * mask on a per CPU basis. * Done in process context under mutex protection. */ static void cfset_session_del(struct cfset_request *p) { list_del(&p->node); } /* Add current request to global bookkeeping. Maintain a counter set bit mask * on a per CPU basis. * Done in process context under mutex protection. */ static void cfset_session_add(struct cfset_request *p) { list_add(&p->node, &cfset_session.head); } /* The /dev/hwctr device access uses PMU_F_IN_USE to mark the device access * path is currently used. * The cpu_cf_events::dev_state is used to denote counter sets in use by this * interface. It is always or'ed in. If this interface is not active, its * value is zero and no additional counter sets will be included. * * The cpu_cf_events::state is used by the perf_event_open SVC and remains * unchanged. * * perf_pmu_enable() and perf_pmu_enable() and its call backs * cpumf_pmu_enable() and cpumf_pmu_disable() are called by the * performance measurement subsystem to enable per process * CPU Measurement counter facility. * The XXX_enable() and XXX_disable functions are used to turn off * x86 performance monitoring interrupt (PMI) during scheduling. * s390 uses these calls to temporarily stop and resume the active CPU * counters sets during scheduling. * * We do allow concurrent access of perf_event_open() SVC and /dev/hwctr * device access. The perf_event_open() SVC interface makes a lot of effort * to only run the counters while the calling process is actively scheduled * to run. * When /dev/hwctr interface is also used at the same time, the counter sets * will keep running, even when the process is scheduled off a CPU. * However this is not a problem and does not lead to wrong counter values * for the perf_event_open() SVC. The current counter value will be recorded * during schedule-in. At schedule-out time the current counter value is * extracted again and the delta is calculated and added to the event. */ /* Stop all counter sets via ioctl interface */ static void cfset_ioctl_off(void *parm) { struct cpu_cf_events *cpuhw = this_cpu_ptr(&cpu_cf_events); struct cfset_call_on_cpu_parm *p = parm; int rc; /* Check if any counter set used by /dev/hwc */ for (rc = CPUMF_CTR_SET_BASIC; rc < CPUMF_CTR_SET_MAX; ++rc) if ((p->sets & cpumf_ctr_ctl[rc])) { if (!atomic_dec_return(&cpuhw->ctr_set[rc])) { ctr_set_disable(&cpuhw->dev_state, cpumf_ctr_ctl[rc]); ctr_set_stop(&cpuhw->dev_state, cpumf_ctr_ctl[rc]); } } /* Keep perf_event_open counter sets */ rc = lcctl(cpuhw->dev_state | cpuhw->state); if (rc) pr_err("Counter set stop %#llx of /dev/%s failed rc=%i\n", cpuhw->state, S390_HWCTR_DEVICE, rc); if (!cpuhw->dev_state) cpuhw->flags &= ~PMU_F_IN_USE; debug_sprintf_event(cf_dbg, 4, "%s rc %d state %#llx dev_state %#llx\n", __func__, rc, cpuhw->state, cpuhw->dev_state); } /* Start counter sets on particular CPU */ static void cfset_ioctl_on(void *parm) { struct cpu_cf_events *cpuhw = this_cpu_ptr(&cpu_cf_events); struct cfset_call_on_cpu_parm *p = parm; int rc; cpuhw->flags |= PMU_F_IN_USE; ctr_set_enable(&cpuhw->dev_state, p->sets); ctr_set_start(&cpuhw->dev_state, p->sets); for (rc = CPUMF_CTR_SET_BASIC; rc < CPUMF_CTR_SET_MAX; ++rc) if ((p->sets & cpumf_ctr_ctl[rc])) atomic_inc(&cpuhw->ctr_set[rc]); rc = lcctl(cpuhw->dev_state | cpuhw->state); /* Start counter sets */ if (!rc) atomic_inc(&p->cpus_ack); else pr_err("Counter set start %#llx of /dev/%s failed rc=%i\n", cpuhw->dev_state | cpuhw->state, S390_HWCTR_DEVICE, rc); debug_sprintf_event(cf_dbg, 4, "%s rc %d state %#llx dev_state %#llx\n", __func__, rc, cpuhw->state, cpuhw->dev_state); } static void cfset_release_cpu(void *p) { struct cpu_cf_events *cpuhw = this_cpu_ptr(&cpu_cf_events); int rc; debug_sprintf_event(cf_dbg, 4, "%s state %#llx dev_state %#llx\n", __func__, cpuhw->state, cpuhw->dev_state); cpuhw->dev_state = 0; rc = lcctl(cpuhw->state); /* Keep perf_event_open counter sets */ if (rc) pr_err("Counter set release %#llx of /dev/%s failed rc=%i\n", cpuhw->state, S390_HWCTR_DEVICE, rc); } /* This modifies the process CPU mask to adopt it to the currently online * CPUs. Offline CPUs can not be addresses. This call terminates the access * and is usually followed by close() or a new iotcl(..., START, ...) which * creates a new request structure. */ static void cfset_all_stop(struct cfset_request *req) { struct cfset_call_on_cpu_parm p = { .sets = req->ctrset, }; cpumask_and(&req->mask, &req->mask, cpu_online_mask); on_each_cpu_mask(&req->mask, cfset_ioctl_off, &p, 1); } /* Release function is also called when application gets terminated without * doing a proper ioctl(..., S390_HWCTR_STOP, ...) command. */ static int cfset_release(struct inode *inode, struct file *file) { mutex_lock(&cfset_ctrset_mutex); /* Open followed by close/exit has no private_data */ if (file->private_data) { cfset_all_stop(file->private_data); cfset_session_del(file->private_data); kfree(file->private_data); file->private_data = NULL; } if (!atomic_dec_return(&cfset_opencnt)) on_each_cpu(cfset_release_cpu, NULL, 1); mutex_unlock(&cfset_ctrset_mutex); hw_perf_event_destroy(NULL); return 0; } static int cfset_open(struct inode *inode, struct file *file) { if (!capable(CAP_SYS_ADMIN)) return -EPERM; mutex_lock(&cfset_ctrset_mutex); if (atomic_inc_return(&cfset_opencnt) == 1) cfset_session_init(); mutex_unlock(&cfset_ctrset_mutex); cpumf_hw_inuse(); file->private_data = NULL; /* nonseekable_open() never fails */ return nonseekable_open(inode, file); } static int cfset_all_start(struct cfset_request *req) { struct cfset_call_on_cpu_parm p = { .sets = req->ctrset, .cpus_ack = ATOMIC_INIT(0), }; cpumask_var_t mask; int rc = 0; if (!alloc_cpumask_var(&mask, GFP_KERNEL)) return -ENOMEM; cpumask_and(mask, &req->mask, cpu_online_mask); on_each_cpu_mask(mask, cfset_ioctl_on, &p, 1); if (atomic_read(&p.cpus_ack) != cpumask_weight(mask)) { on_each_cpu_mask(mask, cfset_ioctl_off, &p, 1); rc = -EIO; debug_sprintf_event(cf_dbg, 4, "%s CPUs missing", __func__); } free_cpumask_var(mask); return rc; } /* Return the maximum required space for all possible CPUs in case one * CPU will be onlined during the START, READ, STOP cycles. * To find out the size of the counter sets, any one CPU will do. They * all have the same counter sets. */ static size_t cfset_needspace(unsigned int sets) { struct cpu_cf_events *cpuhw = get_cpu_ptr(&cpu_cf_events); size_t bytes = 0; int i; for (i = CPUMF_CTR_SET_BASIC; i < CPUMF_CTR_SET_MAX; ++i) { if (!(sets & cpumf_ctr_ctl[i])) continue; bytes += cpum_cf_ctrset_size(i, &cpuhw->info) * sizeof(u64) + sizeof(((struct s390_ctrset_setdata *)0)->set) + sizeof(((struct s390_ctrset_setdata *)0)->no_cnts); } bytes = sizeof(((struct s390_ctrset_read *)0)->no_cpus) + nr_cpu_ids * (bytes + sizeof(((struct s390_ctrset_cpudata *)0)->cpu_nr) + sizeof(((struct s390_ctrset_cpudata *)0)->no_sets)); put_cpu_ptr(&cpu_cf_events); return bytes; } static int cfset_all_copy(unsigned long arg, cpumask_t *mask) { struct s390_ctrset_read __user *ctrset_read; unsigned int cpu, cpus, rc; void __user *uptr; ctrset_read = (struct s390_ctrset_read __user *)arg; uptr = ctrset_read->data; for_each_cpu(cpu, mask) { struct cpu_cf_events *cpuhw = per_cpu_ptr(&cpu_cf_events, cpu); struct s390_ctrset_cpudata __user *ctrset_cpudata; ctrset_cpudata = uptr; rc = put_user(cpu, &ctrset_cpudata->cpu_nr); rc |= put_user(cpuhw->sets, &ctrset_cpudata->no_sets); rc |= copy_to_user(ctrset_cpudata->data, cpuhw->data, cpuhw->used); if (rc) return -EFAULT; uptr += sizeof(struct s390_ctrset_cpudata) + cpuhw->used; cond_resched(); } cpus = cpumask_weight(mask); if (put_user(cpus, &ctrset_read->no_cpus)) return -EFAULT; debug_sprintf_event(cf_dbg, 4, "%s copied %ld\n", __func__, uptr - (void __user *)ctrset_read->data); return 0; } static size_t cfset_cpuset_read(struct s390_ctrset_setdata *p, int ctrset, int ctrset_size, size_t room) { size_t need = 0; int rc = -1; need = sizeof(*p) + sizeof(u64) * ctrset_size; if (need <= room) { p->set = cpumf_ctr_ctl[ctrset]; p->no_cnts = ctrset_size; rc = ctr_stcctm(ctrset, ctrset_size, (u64 *)p->cv); if (rc == 3) /* Nothing stored */ need = 0; } return need; } /* Read all counter sets. */ static void cfset_cpu_read(void *parm) { struct cpu_cf_events *cpuhw = this_cpu_ptr(&cpu_cf_events); struct cfset_call_on_cpu_parm *p = parm; int set, set_size; size_t space; /* No data saved yet */ cpuhw->used = 0; cpuhw->sets = 0; memset(cpuhw->data, 0, sizeof(cpuhw->data)); /* Scan the counter sets */ for (set = CPUMF_CTR_SET_BASIC; set < CPUMF_CTR_SET_MAX; ++set) { struct s390_ctrset_setdata *sp = (void *)cpuhw->data + cpuhw->used; if (!(p->sets & cpumf_ctr_ctl[set])) continue; /* Counter set not in list */ set_size = cpum_cf_ctrset_size(set, &cpuhw->info); space = sizeof(cpuhw->data) - cpuhw->used; space = cfset_cpuset_read(sp, set, set_size, space); if (space) { cpuhw->used += space; cpuhw->sets += 1; } } debug_sprintf_event(cf_dbg, 4, "%s sets %d used %zd\n", __func__, cpuhw->sets, cpuhw->used); } static int cfset_all_read(unsigned long arg, struct cfset_request *req) { struct cfset_call_on_cpu_parm p; cpumask_var_t mask; int rc; if (!alloc_cpumask_var(&mask, GFP_KERNEL)) return -ENOMEM; p.sets = req->ctrset; cpumask_and(mask, &req->mask, cpu_online_mask); on_each_cpu_mask(mask, cfset_cpu_read, &p, 1); rc = cfset_all_copy(arg, mask); free_cpumask_var(mask); return rc; } static long cfset_ioctl_read(unsigned long arg, struct cfset_request *req) { struct s390_ctrset_read read; int ret = -ENODATA; if (req && req->ctrset) { if (copy_from_user(&read, (char __user *)arg, sizeof(read))) return -EFAULT; ret = cfset_all_read(arg, req); } return ret; } static long cfset_ioctl_stop(struct file *file) { struct cfset_request *req = file->private_data; int ret = -ENXIO; if (req) { cfset_all_stop(req); cfset_session_del(req); kfree(req); file->private_data = NULL; ret = 0; } return ret; } static long cfset_ioctl_start(unsigned long arg, struct file *file) { struct s390_ctrset_start __user *ustart; struct s390_ctrset_start start; struct cfset_request *preq; void __user *umask; unsigned int len; int ret = 0; size_t need; if (file->private_data) return -EBUSY; ustart = (struct s390_ctrset_start __user *)arg; if (copy_from_user(&start, ustart, sizeof(start))) return -EFAULT; if (start.version != S390_HWCTR_START_VERSION) return -EINVAL; if (start.counter_sets & ~(cpumf_ctr_ctl[CPUMF_CTR_SET_BASIC] | cpumf_ctr_ctl[CPUMF_CTR_SET_USER] | cpumf_ctr_ctl[CPUMF_CTR_SET_CRYPTO] | cpumf_ctr_ctl[CPUMF_CTR_SET_EXT] | cpumf_ctr_ctl[CPUMF_CTR_SET_MT_DIAG])) return -EINVAL; /* Invalid counter set */ if (!start.counter_sets) return -EINVAL; /* No counter set at all? */ preq = kzalloc(sizeof(*preq), GFP_KERNEL); if (!preq) return -ENOMEM; cpumask_clear(&preq->mask); len = min_t(u64, start.cpumask_len, cpumask_size()); umask = (void __user *)start.cpumask; if (copy_from_user(&preq->mask, umask, len)) { kfree(preq); return -EFAULT; } if (cpumask_empty(&preq->mask)) { kfree(preq); return -EINVAL; } need = cfset_needspace(start.counter_sets); if (put_user(need, &ustart->data_bytes)) { kfree(preq); return -EFAULT; } preq->ctrset = start.counter_sets; ret = cfset_all_start(preq); if (!ret) { cfset_session_add(preq); file->private_data = preq; debug_sprintf_event(cf_dbg, 4, "%s set %#lx need %ld ret %d\n", __func__, preq->ctrset, need, ret); } else { kfree(preq); } return ret; } /* Entry point to the /dev/hwctr device interface. * The ioctl system call supports three subcommands: * S390_HWCTR_START: Start the specified counter sets on a CPU list. The * counter set keeps running until explicitly stopped. Returns the number * of bytes needed to store the counter values. If another S390_HWCTR_START * ioctl subcommand is called without a previous S390_HWCTR_STOP stop * command on the same file descriptor, -EBUSY is returned. * S390_HWCTR_READ: Read the counter set values from specified CPU list given * with the S390_HWCTR_START command. * S390_HWCTR_STOP: Stops the counter sets on the CPU list given with the * previous S390_HWCTR_START subcommand. */ static long cfset_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { int ret; cpus_read_lock(); mutex_lock(&cfset_ctrset_mutex); switch (cmd) { case S390_HWCTR_START: ret = cfset_ioctl_start(arg, file); break; case S390_HWCTR_STOP: ret = cfset_ioctl_stop(file); break; case S390_HWCTR_READ: ret = cfset_ioctl_read(arg, file->private_data); break; default: ret = -ENOTTY; break; } mutex_unlock(&cfset_ctrset_mutex); cpus_read_unlock(); return ret; } static const struct file_operations cfset_fops = { .owner = THIS_MODULE, .open = cfset_open, .release = cfset_release, .unlocked_ioctl = cfset_ioctl, .compat_ioctl = cfset_ioctl, .llseek = no_llseek }; static struct miscdevice cfset_dev = { .name = S390_HWCTR_DEVICE, .minor = MISC_DYNAMIC_MINOR, .fops = &cfset_fops, }; /* Hotplug add of a CPU. Scan through all active processes and add * that CPU to the list of CPUs supplied with ioctl(..., START, ...). */ int cfset_online_cpu(unsigned int cpu) { struct cfset_call_on_cpu_parm p; struct cfset_request *rp; mutex_lock(&cfset_ctrset_mutex); if (!list_empty(&cfset_session.head)) { list_for_each_entry(rp, &cfset_session.head, node) { p.sets = rp->ctrset; cfset_ioctl_on(&p); cpumask_set_cpu(cpu, &rp->mask); } } mutex_unlock(&cfset_ctrset_mutex); return 0; } /* Hotplug remove of a CPU. Scan through all active processes and clear * that CPU from the list of CPUs supplied with ioctl(..., START, ...). */ int cfset_offline_cpu(unsigned int cpu) { struct cfset_call_on_cpu_parm p; struct cfset_request *rp; mutex_lock(&cfset_ctrset_mutex); if (!list_empty(&cfset_session.head)) { list_for_each_entry(rp, &cfset_session.head, node) { p.sets = rp->ctrset; cfset_ioctl_off(&p); cpumask_clear_cpu(cpu, &rp->mask); } } mutex_unlock(&cfset_ctrset_mutex); return 0; } static void cfdiag_read(struct perf_event *event) { debug_sprintf_event(cf_dbg, 3, "%s event %#llx count %ld\n", __func__, event->attr.config, local64_read(&event->count)); } static int get_authctrsets(void) { struct cpu_cf_events *cpuhw; unsigned long auth = 0; enum cpumf_ctr_set i; cpuhw = &get_cpu_var(cpu_cf_events); for (i = CPUMF_CTR_SET_BASIC; i < CPUMF_CTR_SET_MAX; ++i) { if (cpuhw->info.auth_ctl & cpumf_ctr_ctl[i]) auth |= cpumf_ctr_ctl[i]; } put_cpu_var(cpu_cf_events); return auth; } /* Setup the event. Test for authorized counter sets and only include counter * sets which are authorized at the time of the setup. Including unauthorized * counter sets result in specification exception (and panic). */ static int cfdiag_event_init2(struct perf_event *event) { struct perf_event_attr *attr = &event->attr; int err = 0; /* Set sample_period to indicate sampling */ event->hw.config = attr->config; event->hw.sample_period = attr->sample_period; local64_set(&event->hw.period_left, event->hw.sample_period); local64_set(&event->count, 0); event->hw.last_period = event->hw.sample_period; /* Add all authorized counter sets to config_base. The * the hardware init function is either called per-cpu or just once * for all CPUS (event->cpu == -1). This depends on the whether * counting is started for all CPUs or on a per workload base where * the perf event moves from one CPU to another CPU. * Checking the authorization on any CPU is fine as the hardware * applies the same authorization settings to all CPUs. */ event->hw.config_base = get_authctrsets(); /* No authorized counter sets, nothing to count/sample */ if (!event->hw.config_base) err = -EINVAL; debug_sprintf_event(cf_dbg, 5, "%s err %d config_base %#lx\n", __func__, err, event->hw.config_base); return err; } static int cfdiag_event_init(struct perf_event *event) { struct perf_event_attr *attr = &event->attr; int err = -ENOENT; if (event->attr.config != PERF_EVENT_CPUM_CF_DIAG || event->attr.type != event->pmu->type) goto out; /* Raw events are used to access counters directly, * hence do not permit excludes. * This event is useless without PERF_SAMPLE_RAW to return counter set * values as raw data. */ if (attr->exclude_kernel || attr->exclude_user || attr->exclude_hv || !(attr->sample_type & (PERF_SAMPLE_CPU | PERF_SAMPLE_RAW))) { err = -EOPNOTSUPP; goto out; } /* Initialize for using the CPU-measurement counter facility */ cpumf_hw_inuse(); event->destroy = hw_perf_event_destroy; err = cfdiag_event_init2(event); if (unlikely(err)) event->destroy(event); out: return err; } /* Create cf_diag/events/CF_DIAG event sysfs file. This counter is used * to collect the complete counter sets for a scheduled process. Target * are complete counter sets attached as raw data to the artificial event. * This results in complete counter sets available when a process is * scheduled. Contains the delta of every counter while the process was * running. */ CPUMF_EVENT_ATTR(CF_DIAG, CF_DIAG, PERF_EVENT_CPUM_CF_DIAG); static struct attribute *cfdiag_events_attr[] = { CPUMF_EVENT_PTR(CF_DIAG, CF_DIAG), NULL, }; PMU_FORMAT_ATTR(event, "config:0-63"); static struct attribute *cfdiag_format_attr[] = { &format_attr_event.attr, NULL, }; static struct attribute_group cfdiag_events_group = { .name = "events", .attrs = cfdiag_events_attr, }; static struct attribute_group cfdiag_format_group = { .name = "format", .attrs = cfdiag_format_attr, }; static const struct attribute_group *cfdiag_attr_groups[] = { &cfdiag_events_group, &cfdiag_format_group, NULL, }; /* Performance monitoring unit for event CF_DIAG. Since this event * is also started and stopped via the perf_event_open() system call, use * the same event enable/disable call back functions. They do not * have a pointer to the perf_event strcture as first parameter. * * The functions XXX_add, XXX_del, XXX_start and XXX_stop are also common. * Reuse them and distinguish the event (always first parameter) via * 'config' member. */ static struct pmu cf_diag = { .task_ctx_nr = perf_sw_context, .event_init = cfdiag_event_init, .pmu_enable = cpumf_pmu_enable, .pmu_disable = cpumf_pmu_disable, .add = cpumf_pmu_add, .del = cpumf_pmu_del, .start = cpumf_pmu_start, .stop = cpumf_pmu_stop, .read = cfdiag_read, .attr_groups = cfdiag_attr_groups }; /* Calculate memory needed to store all counter sets together with header and * trailer data. This is independent of the counter set authorization which * can vary depending on the configuration. */ static size_t cfdiag_maxsize(struct cpumf_ctr_info *info) { size_t max_size = sizeof(struct cf_trailer_entry); enum cpumf_ctr_set i; for (i = CPUMF_CTR_SET_BASIC; i < CPUMF_CTR_SET_MAX; ++i) { size_t size = cpum_cf_ctrset_size(i, info); if (size) max_size += size * sizeof(u64) + sizeof(struct cf_ctrset_entry); } return max_size; } /* Get the CPU speed, try sampling facility first and CPU attributes second. */ static void cfdiag_get_cpu_speed(void) { unsigned long mhz; if (cpum_sf_avail()) { /* Sampling facility first */ struct hws_qsi_info_block si; memset(&si, 0, sizeof(si)); if (!qsi(&si)) { cfdiag_cpu_speed = si.cpu_speed; return; } } /* Fallback: CPU speed extract static part. Used in case * CPU Measurement Sampling Facility is turned off. */ mhz = __ecag(ECAG_CPU_ATTRIBUTE, 0); if (mhz != -1UL) cfdiag_cpu_speed = mhz & 0xffffffff; } static int cfset_init(void) { struct cpumf_ctr_info info; size_t need; int rc; if (qctri(&info)) return -ENODEV; cfdiag_get_cpu_speed(); /* Make sure the counter set data fits into predefined buffer. */ need = cfdiag_maxsize(&info); if (need > sizeof(((struct cpu_cf_events *)0)->start)) { pr_err("Insufficient memory for PMU(cpum_cf_diag) need=%zu\n", need); return -ENOMEM; } rc = misc_register(&cfset_dev); if (rc) { pr_err("Registration of /dev/%s failed rc=%i\n", cfset_dev.name, rc); goto out; } rc = perf_pmu_register(&cf_diag, "cpum_cf_diag", -1); if (rc) { misc_deregister(&cfset_dev); pr_err("Registration of PMU(cpum_cf_diag) failed with rc=%i\n", rc); } out: return rc; } device_initcall(cpumf_pmu_init);
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