[PATCH 4/4] drm/xe/pmu: Add GT frequency events
Vinay Belgaumkar
vinay.belgaumkar at intel.com
Tue Aug 27 16:41:07 UTC 2024
Define PMU events for GT freq (actual and requested).
PMU events being added -
xe_0000_00_02.0/actual-frequency-gt0/ [Kernel PMU event]
xe_0000_00_02.0/actual-frequency-gt1/ [Kernel PMU event]
xe_0000_00_02.0/requested-frequency-gt0/ [Kernel PMU event]
xe_0000_00_02.0/requested-frequency-gt1/ [Kernel PMU event]
These events will aggregate freq in Mhz just like sysfs. The
implementation has been borrowed from i915 driver.
Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
Signed-off-by: Vinay Belgaumkar <vinay.belgaumkar at intel.com>
---
drivers/gpu/drm/xe/xe_pmu.c | 157 ++++++++++++++++++++++++++++++
drivers/gpu/drm/xe/xe_pmu_types.h | 4 +
include/uapi/drm/xe_drm.h | 5 +
3 files changed, 166 insertions(+)
diff --git a/drivers/gpu/drm/xe/xe_pmu.c b/drivers/gpu/drm/xe/xe_pmu.c
index 5b9c7966ec75..671dc2caf37d 100644
--- a/drivers/gpu/drm/xe/xe_pmu.c
+++ b/drivers/gpu/drm/xe/xe_pmu.c
@@ -44,6 +44,12 @@ static unsigned int other_bit(const u64 config)
case XE_PMU_RC6_RESIDENCY:
val = __XE_PMU_RC6_RESIDENCY_ENABLED;
break;
+ case XE_PMU_ACTUAL_FREQUENCY:
+ val = __XE_PMU_ACTUAL_FREQUENCY_ENABLED;
+ break;
+ case XE_PMU_REQUESTED_FREQUENCY:
+ val = __XE_PMU_REQUESTED_FREQUENCY_ENABLED;
+ break;
default:
/*
* Events that do not require sampling, or tracking state
@@ -60,6 +66,22 @@ static unsigned int config_bit(const u64 config)
return other_bit(config);
}
+static u32 config_mask(const u64 config)
+{
+ unsigned int bit = config_bit(config);
+
+ if (__builtin_constant_p(config))
+ BUILD_BUG_ON(bit >
+ BITS_PER_TYPE(typeof_member(struct xe_pmu,
+ enable)) - 1);
+ else
+ WARN_ON_ONCE(bit >
+ BITS_PER_TYPE(typeof_member(struct xe_pmu,
+ enable)) - 1);
+
+ return BIT(config_bit(config));
+}
+
static unsigned int event_bit(struct perf_event *event)
{
return config_bit(event->attr.config);
@@ -88,6 +110,10 @@ config_status(struct xe_device *xe, u64 config)
if (xe->info.skip_guc_pc)
return -ENODEV;
break;
+ case XE_PMU_ACTUAL_FREQUENCY:
+ fallthrough;
+ case XE_PMU_REQUESTED_FREQUENCY:
+ break;
default:
return -ENOENT;
}
@@ -150,6 +176,12 @@ store_sample(struct xe_pmu *pmu, unsigned int gt_id, int sample, u64 val)
pmu->event_sample[gt_id][sample].cur = val;
}
+static void
+add_sample_mult(struct xe_pmu *pmu, unsigned int gt_id, int sample, u32 val, u32 mul)
+{
+ pmu->event_sample[gt_id][sample].cur += mul_u32_u32(val, mul);
+}
+
static u64 get_rc6(struct xe_gt *gt)
{
struct xe_device *xe = gt_to_xe(gt);
@@ -195,6 +227,7 @@ static u64 __xe_pmu_event_read(struct perf_event *event)
{
struct xe_device *xe =
container_of(event->pmu, typeof(*xe), pmu.base);
+ struct xe_pmu *pmu = &xe->pmu;
const unsigned int gt_id = config_gt_id(event->attr.config);
const u64 config = event->attr.config;
struct xe_gt *gt = xe_device_get_gt(xe, gt_id);
@@ -204,6 +237,18 @@ static u64 __xe_pmu_event_read(struct perf_event *event)
case XE_PMU_RC6_RESIDENCY:
val = get_rc6(gt);
break;
+ case XE_PMU_ACTUAL_FREQUENCY:
+ val =
+ div_u64(read_sample(pmu, gt_id,
+ __XE_SAMPLE_FREQ_ACT),
+ USEC_PER_SEC /* to MHz */);
+ break;
+ case XE_PMU_REQUESTED_FREQUENCY:
+ val =
+ div_u64(read_sample(pmu, gt_id,
+ __XE_SAMPLE_FREQ_REQ),
+ USEC_PER_SEC /* to MHz */);
+ break;
default:
drm_warn(>->tile->xe->drm, "unknown pmu event\n");
}
@@ -233,6 +278,109 @@ static void xe_pmu_event_read(struct perf_event *event)
local64_add(new - prev, &event->count);
}
+static u32 frequency_enabled_mask(void)
+{
+ unsigned int i;
+ u32 mask = 0;
+
+ for (i = 0; i < XE_PMU_MAX_GT; i++)
+ mask |= config_mask(__XE_PMU_ACTUAL_FREQUENCY(i)) |
+ config_mask(__XE_PMU_REQUESTED_FREQUENCY(i));
+
+ return mask;
+}
+
+static bool
+frequency_sampling_enabled(struct xe_pmu *pmu, unsigned int gt)
+{
+ return pmu->enable &
+ (config_mask(__XE_PMU_ACTUAL_FREQUENCY(gt)) |
+ config_mask(__XE_PMU_REQUESTED_FREQUENCY(gt)));
+}
+
+static void
+frequency_sample(struct xe_gt *gt, unsigned int period_ns)
+{
+ struct xe_device *xe = gt_to_xe(gt);
+ const unsigned int gt_id = gt->info.id;
+ struct xe_pmu *pmu = &xe->pmu;
+ bool device_awake;
+ int ret;
+ u32 cur_freq;
+
+ if (!frequency_sampling_enabled(pmu, gt_id))
+ return;
+
+ /* Report 0/0 (actual/requested) frequency while GT is suspended. */
+ device_awake = xe_pm_runtime_get_if_active(xe);
+ if (!device_awake)
+ return;
+
+ if (pmu->enable & config_mask(__XE_PMU_ACTUAL_FREQUENCY(gt_id))) {
+ u32 val;
+
+ /*
+ * We take a quick peek here without using forcewake
+ * so that we don't perturb the system under observation
+ * (forcewake => !rc6 => increased power use). We expect
+ * that if the read fails because it is outside of the
+ * mmio power well, then it will return 0 -- in which
+ * case we assume the system is running at the intended
+ * frequency. Fortunately, the read should rarely fail!
+ */
+ val = xe_guc_pc_get_act_freq(>->uc.guc.pc);
+
+ add_sample_mult(pmu, gt_id, __XE_SAMPLE_FREQ_ACT,
+ val, period_ns / 1000);
+ }
+
+ if (pmu->enable & config_mask(__XE_PMU_REQUESTED_FREQUENCY(gt_id))) {
+ ret = xe_guc_pc_get_cur_freq(>->uc.guc.pc, &cur_freq);
+ if (!ret)
+ add_sample_mult(pmu, gt_id, __XE_SAMPLE_FREQ_REQ,
+ cur_freq,
+ period_ns / 1000);
+ }
+
+ xe_pm_runtime_put(xe);
+}
+
+static enum hrtimer_restart xe_sample(struct hrtimer *hrtimer)
+{
+ struct xe_pmu *pmu = container_of(hrtimer, struct xe_pmu, timer);
+ struct xe_device *xe = container_of(pmu, typeof(*xe), pmu);
+ const u64 freq = xe_modparam.pmu_sampling_freq;
+ u64 period = max_t(u64, 10000, NSEC_PER_SEC / freq);
+ unsigned int period_ns;
+ struct xe_gt *gt;
+ unsigned int i;
+ ktime_t now;
+
+ if (!READ_ONCE(pmu->timer_enabled))
+ return HRTIMER_NORESTART;
+
+ now = ktime_get();
+ period_ns = ktime_to_ns(ktime_sub(now, pmu->timer_last));
+ pmu->timer_last = now;
+
+ /*
+ * Strictly speaking the passed in period may not be 100% accurate for
+ * all internal calculation, since some amount of time can be spent on
+ * grabbing the forcewake. However the potential error from timer call-
+ * back delay greatly dominates this so we keep it simple.
+ */
+
+ for_each_gt(gt, xe, i) {
+ if (!(pmu->active_gts & BIT(i)))
+ continue;
+ frequency_sample(gt, period_ns);
+ }
+
+ hrtimer_forward(hrtimer, now, ns_to_ktime(period));
+
+ return HRTIMER_RESTART;
+}
+
static bool pmu_needs_timer(struct xe_pmu *pmu)
{
u32 enable;
@@ -244,6 +392,12 @@ static bool pmu_needs_timer(struct xe_pmu *pmu)
*/
enable = pmu->enable;
+ /*
+ * Mask out all the ones which do not need the timer, or in
+ * other words keep all the ones that could need the timer.
+ */
+ enable &= frequency_enabled_mask();
+
/*
* If some bits remain it means we need the sampling timer running.
*/
@@ -420,6 +574,8 @@ create_event_attributes(struct xe_pmu *pmu)
const char *unit;
} events[] = {
__event(0, "rc6-residency", "ms"),
+ __event(1, "actual-frequency", "M"),
+ __event(2, "requested-frequency", "M"),
};
struct perf_pmu_events_attr *pmu_attr = NULL, *pmu_iter;
@@ -710,6 +866,7 @@ void xe_pmu_register(struct xe_pmu *pmu)
spin_lock_init(&pmu->lock);
hrtimer_init(&pmu->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ pmu->timer.function = xe_sample;
pmu->cpuhp.cpu = -1;
pmu->name = kasprintf(GFP_KERNEL,
diff --git a/drivers/gpu/drm/xe/xe_pmu_types.h b/drivers/gpu/drm/xe/xe_pmu_types.h
index 32835f6987d2..073964be473d 100644
--- a/drivers/gpu/drm/xe/xe_pmu_types.h
+++ b/drivers/gpu/drm/xe/xe_pmu_types.h
@@ -13,6 +13,8 @@
enum {
__XE_SAMPLE_RC6,
__XE_SAMPLE_RC6_LAST_REPORTED,
+ __XE_SAMPLE_FREQ_ACT,
+ __XE_SAMPLE_FREQ_REQ,
__XE_NUM_PMU_SAMPLERS
};
@@ -23,6 +25,8 @@ enum {
* current state.
*/
enum xe_pmu_tracked_events {
+ __XE_PMU_ACTUAL_FREQUENCY_ENABLED,
+ __XE_PMU_REQUESTED_FREQUENCY_ENABLED,
__XE_PMU_RC6_RESIDENCY_ENABLED,
__XE_PMU_TRACKED_EVENT_COUNT, /* count marker */
};
diff --git a/include/uapi/drm/xe_drm.h b/include/uapi/drm/xe_drm.h
index 5b85ee1cfc0b..6f39e08f6e8d 100644
--- a/include/uapi/drm/xe_drm.h
+++ b/include/uapi/drm/xe_drm.h
@@ -1425,7 +1425,12 @@ struct drm_xe_wait_user_fence {
#define __XE_PMU_OTHER(x) ___XE_PMU_OTHER(0, x)
#define XE_PMU_RC6_RESIDENCY __XE_PMU_OTHER(0)
+#define XE_PMU_ACTUAL_FREQUENCY __XE_PMU_OTHER(1)
+#define XE_PMU_REQUESTED_FREQUENCY __XE_PMU_OTHER(2)
+
#define __XE_PMU_RC6_RESIDENCY(gt) ___XE_PMU_OTHER(gt, 0)
+#define __XE_PMU_ACTUAL_FREQUENCY(gt) ___XE_PMU_OTHER(gt, 1)
+#define __XE_PMU_REQUESTED_FREQUENCY(gt) ___XE_PMU_OTHER(gt, 2)
/**
* enum drm_xe_observation_type - Observation stream types
--
2.38.1
More information about the Intel-xe
mailing list