[PATCH v2 7/7] perf: arm_spe: Add support for SPEv1.2 inverted event filtering

From: Rob Herring
Date: Wed Oct 19 2022 - 15:11:59 EST


Arm SPEv1.2 (Arm v8.7/v9.2) adds a new feature called Inverted Event
Filter which excludes samples matching the event filter. The feature
mirrors the existing event filter in PMSEVFR_EL1 adding a new register,
PMSNEVFR_EL1, which has the same event bit assignments.

Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
---
v2:
- Update for auto generated register defines
- Avoid accessing SYS_PMSNEVFR_EL1 on < v8.7
---
drivers/perf/arm_spe_pmu.c | 45 +++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 45 insertions(+)

diff --git a/drivers/perf/arm_spe_pmu.c b/drivers/perf/arm_spe_pmu.c
index 0b9b847919d0..ab5fcf02a4ca 100644
--- a/drivers/perf/arm_spe_pmu.c
+++ b/drivers/perf/arm_spe_pmu.c
@@ -85,6 +85,7 @@ struct arm_spe_pmu {
#define SPE_PMU_FEAT_ARCH_INST (1UL << 3)
#define SPE_PMU_FEAT_LDS (1UL << 4)
#define SPE_PMU_FEAT_ERND (1UL << 5)
+#define SPE_PMU_FEAT_INV_FILT_EVT (1UL << 6)
#define SPE_PMU_FEAT_DEV_PROBED (1UL << 63)
u64 features;

@@ -202,6 +203,10 @@ static const struct attribute_group arm_spe_pmu_cap_group = {
#define ATTR_CFG_FLD_min_latency_LO 0
#define ATTR_CFG_FLD_min_latency_HI 11

+#define ATTR_CFG_FLD_inv_event_filter_CFG config3 /* PMSNEVFR_EL1 */
+#define ATTR_CFG_FLD_inv_event_filter_LO 0
+#define ATTR_CFG_FLD_inv_event_filter_HI 63
+
/* Why does everything I do descend into this? */
#define __GEN_PMU_FORMAT_ATTR(cfg, lo, hi) \
(lo) == (hi) ? #cfg ":" #lo "\n" : #cfg ":" #lo "-" #hi
@@ -232,6 +237,7 @@ GEN_PMU_FORMAT_ATTR(branch_filter);
GEN_PMU_FORMAT_ATTR(load_filter);
GEN_PMU_FORMAT_ATTR(store_filter);
GEN_PMU_FORMAT_ATTR(event_filter);
+GEN_PMU_FORMAT_ATTR(inv_event_filter);
GEN_PMU_FORMAT_ATTR(min_latency);

static struct attribute *arm_spe_pmu_formats_attr[] = {
@@ -243,12 +249,27 @@ static struct attribute *arm_spe_pmu_formats_attr[] = {
&format_attr_load_filter.attr,
&format_attr_store_filter.attr,
&format_attr_event_filter.attr,
+ &format_attr_inv_event_filter.attr,
&format_attr_min_latency.attr,
NULL,
};

+static umode_t arm_spe_pmu_format_attr_is_visible(struct kobject *kobj,
+ struct attribute *attr,
+ int unused)
+ {
+ struct device *dev = kobj_to_dev(kobj);
+ struct arm_spe_pmu *spe_pmu = dev_get_drvdata(dev);
+
+ if (attr == &format_attr_inv_event_filter.attr && !(spe_pmu->features & SPE_PMU_FEAT_INV_FILT_EVT))
+ return 0;
+
+ return attr->mode;
+}
+
static const struct attribute_group arm_spe_pmu_format_group = {
.name = "format",
+ .is_visible = arm_spe_pmu_format_attr_is_visible,
.attrs = arm_spe_pmu_formats_attr,
};

@@ -343,6 +364,9 @@ static u64 arm_spe_event_to_pmsfcr(struct perf_event *event)
if (ATTR_CFG_GET_FLD(attr, event_filter))
reg |= PMSFCR_EL1_FE;

+ if (ATTR_CFG_GET_FLD(attr, inv_event_filter))
+ reg |= PMSFCR_EL1_FnE;
+
if (ATTR_CFG_GET_FLD(attr, min_latency))
reg |= PMSFCR_EL1_FL;

@@ -355,6 +379,12 @@ static u64 arm_spe_event_to_pmsevfr(struct perf_event *event)
return ATTR_CFG_GET_FLD(attr, event_filter);
}

+static u64 arm_spe_event_to_pmsnevfr(struct perf_event *event)
+{
+ struct perf_event_attr *attr = &event->attr;
+ return ATTR_CFG_GET_FLD(attr, inv_event_filter);
+}
+
static u64 arm_spe_event_to_pmslatfr(struct perf_event *event)
{
struct perf_event_attr *attr = &event->attr;
@@ -703,6 +733,9 @@ static int arm_spe_pmu_event_init(struct perf_event *event)
if (arm_spe_event_to_pmsevfr(event) & arm_spe_pmsevfr_res0(spe_pmu->pmsver))
return -EOPNOTSUPP;

+ if (arm_spe_event_to_pmsnevfr(event) & arm_spe_pmsevfr_res0(spe_pmu->pmsver))
+ return -EOPNOTSUPP;
+
if (attr->exclude_idle)
return -EOPNOTSUPP;

@@ -721,6 +754,10 @@ static int arm_spe_pmu_event_init(struct perf_event *event)
!(spe_pmu->features & SPE_PMU_FEAT_FILT_EVT))
return -EOPNOTSUPP;

+ if ((FIELD_GET(PMSFCR_EL1_FnE, reg)) &&
+ !(spe_pmu->features & SPE_PMU_FEAT_INV_FILT_EVT))
+ return -EOPNOTSUPP;
+
if ((FIELD_GET(PMSFCR_EL1_FT, reg)) &&
!(spe_pmu->features & SPE_PMU_FEAT_FILT_TYP))
return -EOPNOTSUPP;
@@ -756,6 +793,11 @@ static void arm_spe_pmu_start(struct perf_event *event, int flags)
reg = arm_spe_event_to_pmsevfr(event);
write_sysreg_s(reg, SYS_PMSEVFR_EL1);

+ if (spe_pmu->features & SPE_PMU_FEAT_INV_FILT_EVT) {
+ reg = arm_spe_event_to_pmsnevfr(event);
+ write_sysreg_s(reg, SYS_PMSNEVFR_EL1);
+ }
+
reg = arm_spe_event_to_pmslatfr(event);
write_sysreg_s(reg, SYS_PMSLATFR_EL1);

@@ -990,6 +1032,9 @@ static void __arm_spe_pmu_dev_probe(void *info)
if (FIELD_GET(PMSIDR_EL1_FE, reg))
spe_pmu->features |= SPE_PMU_FEAT_FILT_EVT;

+ if (FIELD_GET(PMSIDR_EL1_FnE, reg))
+ spe_pmu->features |= SPE_PMU_FEAT_INV_FILT_EVT;
+
if (FIELD_GET(PMSIDR_EL1_FT, reg))
spe_pmu->features |= SPE_PMU_FEAT_FILT_TYP;


--
b4 0.11.0-dev