diff options
Diffstat (limited to 'drivers/perf/arm_pmuv3.c')
| -rw-r--r-- | drivers/perf/arm_pmuv3.c | 79 |
1 files changed, 78 insertions, 1 deletions
diff --git a/drivers/perf/arm_pmuv3.c b/drivers/perf/arm_pmuv3.c index 2ba215f74d92..23fa6c5da82c 100644 --- a/drivers/perf/arm_pmuv3.c +++ b/drivers/perf/arm_pmuv3.c @@ -309,10 +309,22 @@ static const struct attribute_group armv8_pmuv3_events_attr_group = { #define ATTR_CFG_FLD_rdpmc_CFG config1 #define ATTR_CFG_FLD_rdpmc_LO 1 #define ATTR_CFG_FLD_rdpmc_HI 1 +#define ATTR_CFG_FLD_threshold_count_CFG config1 /* PMEVTYPER.TC[0] */ +#define ATTR_CFG_FLD_threshold_count_LO 2 +#define ATTR_CFG_FLD_threshold_count_HI 2 +#define ATTR_CFG_FLD_threshold_compare_CFG config1 /* PMEVTYPER.TC[2:1] */ +#define ATTR_CFG_FLD_threshold_compare_LO 3 +#define ATTR_CFG_FLD_threshold_compare_HI 4 +#define ATTR_CFG_FLD_threshold_CFG config1 /* PMEVTYPER.TH */ +#define ATTR_CFG_FLD_threshold_LO 5 +#define ATTR_CFG_FLD_threshold_HI 16 GEN_PMU_FORMAT_ATTR(event); GEN_PMU_FORMAT_ATTR(long); GEN_PMU_FORMAT_ATTR(rdpmc); +GEN_PMU_FORMAT_ATTR(threshold_count); +GEN_PMU_FORMAT_ATTR(threshold_compare); +GEN_PMU_FORMAT_ATTR(threshold); static int sysctl_perf_user_access __read_mostly; @@ -326,10 +338,27 @@ static bool armv8pmu_event_want_user_access(struct perf_event *event) return ATTR_CFG_GET_FLD(&event->attr, rdpmc); } +static u8 armv8pmu_event_threshold_control(struct perf_event_attr *attr) +{ + u8 th_compare = ATTR_CFG_GET_FLD(attr, threshold_compare); + u8 th_count = ATTR_CFG_GET_FLD(attr, threshold_count); + + /* + * The count bit is always the bottom bit of the full control field, and + * the comparison is the upper two bits, but it's not explicitly + * labelled in the Arm ARM. For the Perf interface we split it into two + * fields, so reconstruct it here. + */ + return (th_compare << 1) | th_count; +} + static struct attribute *armv8_pmuv3_format_attrs[] = { &format_attr_event.attr, &format_attr_long.attr, &format_attr_rdpmc.attr, + &format_attr_threshold.attr, + &format_attr_threshold_compare.attr, + &format_attr_threshold_count.attr, NULL, }; @@ -379,10 +408,38 @@ static ssize_t bus_width_show(struct device *dev, struct device_attribute *attr, static DEVICE_ATTR_RO(bus_width); +static u32 threshold_max(struct arm_pmu *cpu_pmu) +{ + /* + * PMMIR.THWIDTH is readable and non-zero on aarch32, but it would be + * impossible to write the threshold in the upper 32 bits of PMEVTYPER. + */ + if (IS_ENABLED(CONFIG_ARM)) + return 0; + + /* + * The largest value that can be written to PMEVTYPER<n>_EL0.TH is + * (2 ^ PMMIR.THWIDTH) - 1. + */ + return (1 << FIELD_GET(ARMV8_PMU_THWIDTH, cpu_pmu->reg_pmmir)) - 1; +} + +static ssize_t threshold_max_show(struct device *dev, + struct device_attribute *attr, char *page) +{ + struct pmu *pmu = dev_get_drvdata(dev); + struct arm_pmu *cpu_pmu = container_of(pmu, struct arm_pmu, pmu); + + return sysfs_emit(page, "0x%08x\n", threshold_max(cpu_pmu)); +} + +static DEVICE_ATTR_RO(threshold_max); + static struct attribute *armv8_pmuv3_caps_attrs[] = { &dev_attr_slots.attr, &dev_attr_bus_slots.attr, &dev_attr_bus_width.attr, + &dev_attr_threshold_max.attr, NULL, }; @@ -566,7 +623,7 @@ static void armv8pmu_write_counter(struct perf_event *event, u64 value) armv8pmu_write_hw_counter(event, value); } -static void armv8pmu_write_evtype(int idx, u32 val) +static void armv8pmu_write_evtype(int idx, unsigned long val) { u32 counter = ARMV8_IDX_TO_COUNTER(idx); unsigned long mask = ARMV8_PMU_EVTYPE_EVENT | @@ -935,6 +992,10 @@ static int armv8pmu_set_event_filter(struct hw_perf_event *event, struct perf_event_attr *attr) { unsigned long config_base = 0; + struct perf_event *perf_event = container_of(attr, struct perf_event, + attr); + struct arm_pmu *cpu_pmu = to_arm_pmu(perf_event->pmu); + u32 th; if (attr->exclude_idle) { pr_debug("ARM performance counters do not support mode exclusion\n"); @@ -969,6 +1030,22 @@ static int armv8pmu_set_event_filter(struct hw_perf_event *event, config_base |= ARMV8_PMU_EXCLUDE_EL0; /* + * If FEAT_PMUv3_TH isn't implemented, then THWIDTH (threshold_max) will + * be 0 and will also trigger this check, preventing it from being used. + */ + th = ATTR_CFG_GET_FLD(attr, threshold); + if (th > threshold_max(cpu_pmu)) { + pr_debug("PMU event threshold exceeds max value\n"); + return -EINVAL; + } + + if (IS_ENABLED(CONFIG_ARM64) && th) { + config_base |= FIELD_PREP(ARMV8_PMU_EVTYPE_TH, th); + config_base |= FIELD_PREP(ARMV8_PMU_EVTYPE_TC, + armv8pmu_event_threshold_control(attr)); + } + + /* * Install the filter into config_base as this is used to * construct the event type. */ |