[PATCH 2/2] arm64: perf: Expose Cortex-A53 micro architectural events

From: Florian Fainelli
Date: Thu Apr 04 2019 - 19:25:56 EST


Add a variety of useful Cortex-A53 PMU specific events which were
recently found useful during a debug session.

Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
---
arch/arm64/kernel/perf_event.c | 118 ++++++++++++++++++++++++++++++++-
1 file changed, 116 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c
index 2d30922692b1..ef4105908830 100644
--- a/arch/arm64/kernel/perf_event.c
+++ b/arch/arm64/kernel/perf_event.c
@@ -31,7 +31,23 @@
#include <linux/platform_device.h>

/* ARMv8 Cortex-A53 specific event types. */
+#define ARMV8_A53_PERFCTR_EXT_MEM_REQ 0xC0
+#define ARMV8_A53_PERFCTR_NC_EXT_MEM_REQ 0xC1
#define ARMV8_A53_PERFCTR_PREF_LINEFILL 0xC2
+#define ARMV8_A53_PERFCTR_I_CACHE_THROTTLE 0xC3
+#define ARMV8_A53_PERFCTR_ENT_READ_ALLOC 0xC4
+#define ARMV8_A53_PERFCTR_READ_ALLOC_MODE 0xC5
+#define ARMV8_A53_PERFCTR_PRE_DECODE_ERROR 0xC6
+#define ARMV8_A53_PERFCTR_DATA_WR_STALL 0xC7
+#define ARMV8_A53_PERFCTR_SCU_SNOOP_OTHER_CPU 0xC8
+#define ARMV8_A53_PERFCTR_COND_BRANCH_EXEC 0xC9
+#define ARMV8_A53_PERFCTR_INDIR_BRANCH_MISPRED 0xCA
+#define ARMV8_A53_PERFCTR_INDIR_BRANCH_MISPRED_COMP 0xCB
+#define ARMV8_A53_PERFCTR_COND_BRANCH_MISPRED 0xCC
+#define ARMV8_A53_PERFCTR_L1I_CACHE_MEM_ERR 0xD0
+#define ARMV8_A53_PERFCTR_L1D_CACHE_MEM_ERR 0xD1
+#define ARMV8_A53_PERFCTR_TLB_MEM_ERR 0xD2
+#define ARMV8_A53_PERFCTR_MAX_EVENTS 0xD3

/* ARMv8 Cavium ThunderX specific event types. */
#define ARMV8_THUNDER_PERFCTR_L1D_CACHE_MISS_ST 0xE9
@@ -349,6 +365,82 @@ static struct attribute_group armv8_pmuv3_format_attr_group = {
.attrs = armv8_pmuv3_format_attrs,
};

+#define ARMV8_CORTEXA53_EVENT_ATTR_RESOLVE(m) #m
+#define ARMV8_CORTEXA53_EVENT_ATTR(name, config) \
+ PMU_EVENT_ATTR(name, armv8_cortex_a53_event_attr_##name, \
+ config, armv8pmu_events_sysfs_show)
+
+ARMV8_CORTEXA53_EVENT_ATTR(ext_mem_req, ARMV8_A53_PERFCTR_EXT_MEM_REQ);
+ARMV8_CORTEXA53_EVENT_ATTR(nc_ext_mem_req, ARMV8_A53_PERFCTR_NC_EXT_MEM_REQ);
+ARMV8_CORTEXA53_EVENT_ATTR(pref_linefill, ARMV8_A53_PERFCTR_PREF_LINEFILL);
+ARMV8_CORTEXA53_EVENT_ATTR(i_cache_throttle, ARMV8_A53_PERFCTR_I_CACHE_THROTTLE);
+ARMV8_CORTEXA53_EVENT_ATTR(enter_read_allocate, ARMV8_A53_PERFCTR_ENT_READ_ALLOC);
+ARMV8_CORTEXA53_EVENT_ATTR(read_allocate_mode, ARMV8_A53_PERFCTR_READ_ALLOC_MODE);
+ARMV8_CORTEXA53_EVENT_ATTR(pre_decode_error, ARMV8_A53_PERFCTR_PRE_DECODE_ERROR);
+ARMV8_CORTEXA53_EVENT_ATTR(data_write_stall, ARMV8_A53_PERFCTR_DATA_WR_STALL);
+ARMV8_CORTEXA53_EVENT_ATTR(scu_snoop_other_cpu, ARMV8_A53_PERFCTR_SCU_SNOOP_OTHER_CPU);
+ARMV8_CORTEXA53_EVENT_ATTR(cond_branch_exec, ARMV8_A53_PERFCTR_COND_BRANCH_EXEC);
+ARMV8_CORTEXA53_EVENT_ATTR(indir_br_pred, ARMV8_A53_PERFCTR_INDIR_BRANCH_MISPRED);
+ARMV8_CORTEXA53_EVENT_ATTR(indir_br_pred_comp, ARMV8_A53_PERFCTR_INDIR_BRANCH_MISPRED_COMP);
+ARMV8_CORTEXA53_EVENT_ATTR(cond_br_mis_pred, ARMV8_A53_PERFCTR_COND_BRANCH_MISPRED);
+ARMV8_CORTEXA53_EVENT_ATTR(l1i_cache_mem_err, ARMV8_A53_PERFCTR_L1I_CACHE_MEM_ERR);
+ARMV8_CORTEXA53_EVENT_ATTR(l1d_cache_mem_err, ARMV8_A53_PERFCTR_L1D_CACHE_MEM_ERR);
+ARMV8_CORTEXA53_EVENT_ATTR(tlb_mem_err, ARMV8_A53_PERFCTR_TLB_MEM_ERR);
+
+static struct attribute *armv8_cortex_a53_event_attrs[] = {
+ ARMV8_PMUV3_EVENT_ATTRS
+ &armv8_cortex_a53_event_attr_ext_mem_req.attr.attr,
+ &armv8_cortex_a53_event_attr_nc_ext_mem_req.attr.attr,
+ &armv8_cortex_a53_event_attr_pref_linefill.attr.attr,
+ &armv8_cortex_a53_event_attr_i_cache_throttle.attr.attr,
+ &armv8_cortex_a53_event_attr_enter_read_allocate.attr.attr,
+ &armv8_cortex_a53_event_attr_read_allocate_mode.attr.attr,
+ &armv8_cortex_a53_event_attr_pre_decode_error.attr.attr,
+ &armv8_cortex_a53_event_attr_data_write_stall.attr.attr,
+ &armv8_cortex_a53_event_attr_scu_snoop_other_cpu.attr.attr,
+ &armv8_cortex_a53_event_attr_cond_branch_exec.attr.attr,
+ &armv8_cortex_a53_event_attr_indir_br_pred.attr.attr,
+ &armv8_cortex_a53_event_attr_indir_br_pred_comp.attr.attr,
+ &armv8_cortex_a53_event_attr_cond_br_mis_pred.attr.attr,
+ &armv8_cortex_a53_event_attr_l1i_cache_mem_err.attr.attr,
+ &armv8_cortex_a53_event_attr_l1d_cache_mem_err.attr.attr,
+ &armv8_cortex_a53_event_attr_tlb_mem_err.attr.attr,
+ NULL
+};
+
+static umode_t
+armv8_cortex_a53_pmu_event_attr_is_visible(struct kobject *kobj,
+ struct attribute *attr, int unused)
+{
+ struct device *dev = kobj_to_dev(kobj);
+ struct pmu *pmu = dev_get_drvdata(dev);
+ struct arm_pmu *cpu_pmu = container_of(pmu, struct arm_pmu, pmu);
+ struct perf_pmu_events_attr *pmu_attr;
+
+ pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr.attr);
+
+ if (pmu_attr->id < ARMV8_PMUV3_MAX_COMMON_EVENTS &&
+ test_bit(pmu_attr->id, cpu_pmu->pmceid_bitmap))
+ return attr->mode;
+
+ if (pmu_attr->id >= ARMV8_A53_PERFCTR_EXT_MEM_REQ &&
+ pmu_attr->id < ARMV8_A53_PERFCTR_MAX_EVENTS)
+ return attr->mode;
+
+ pmu_attr->id -= ARMV8_PMUV3_EXT_COMMON_EVENT_BASE;
+ if (pmu_attr->id < ARMV8_PMUV3_MAX_COMMON_EVENTS &&
+ test_bit(pmu_attr->id, cpu_pmu->pmceid_ext_bitmap))
+ return attr->mode;
+
+ return 0;
+}
+
+static struct attribute_group armv8_cortex_a53_events_attr_group = {
+ .name = "events",
+ .attrs = armv8_cortex_a53_event_attrs,
+ .is_visible = armv8_cortex_a53_pmu_event_attr_is_visible,
+};
+
/*
* Perf Events' indices
*/
@@ -910,7 +1002,29 @@ static int armv8_pmuv3_map_event(struct perf_event *event)

static int armv8_a53_map_event(struct perf_event *event)
{
- return __armv8_pmuv3_map_event(event, NULL, &armv8_a53_perf_cache_map);
+ int hw_event_id;
+ struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
+
+ hw_event_id = armpmu_map_event(event, &armv8_pmuv3_perf_map,
+ &armv8_pmuv3_perf_cache_map,
+ ARMV8_PMU_EVTYPE_EVENT);
+
+ if (armv8pmu_event_is_64bit(event))
+ event->hw.flags |= ARMPMU_EVT_64BIT;
+
+ /* Only expose micro/arch events supported by this PMU */
+ if ((hw_event_id > 0) && (hw_event_id < ARMV8_PMUV3_MAX_COMMON_EVENTS)
+ && test_bit(hw_event_id, armpmu->pmceid_bitmap)) {
+ return hw_event_id;
+ }
+
+ /* Expose Cortex-A53 specific events */
+ if (hw_event_id >= ARMV8_A53_PERFCTR_EXT_MEM_REQ &&
+ hw_event_id <= ARMV8_A53_PERFCTR_MAX_EVENTS)
+ return hw_event_id;
+
+ return armpmu_map_event(event, NULL, &armv8_a53_perf_cache_map,
+ ARMV8_PMU_EVTYPE_EVENT);
}

static int armv8_a57_map_event(struct perf_event *event)
@@ -1057,7 +1171,7 @@ static int armv8_a53_pmu_init(struct arm_pmu *cpu_pmu)
cpu_pmu->name = "armv8_cortex_a53";
cpu_pmu->map_event = armv8_a53_map_event;
cpu_pmu->attr_groups[ARMPMU_ATTR_GROUP_EVENTS] =
- &armv8_pmuv3_events_attr_group;
+ &armv8_cortex_a53_events_attr_group;
cpu_pmu->attr_groups[ARMPMU_ATTR_GROUP_FORMATS] =
&armv8_pmuv3_format_attr_group;

--
2.17.1