From: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> commit 88a9c66d998b1d2dac412fcd458c5d17d70513c8 upstream. The rc6 residency starts ticking from 0 from BIOS POST, but the kernel starts measuring the time from its boot. If we start measuruing I915_PMU_RC6_RESIDENCY while the GT is idle, we start our sampling from 0 and then upon first activity (park/unpark) add in all the rc6 residency since boot. After the first park with the sampler engaged, the sleep/active counters are aligned. v2: With a wakeref to be sure Closes: https://gitlab.freedesktop.org/drm/intel/issues/973 Fixes: df6a42053513 ("drm/i915/pmu: Ensure monotonic rc6") Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Cc: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx> Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/20200114105648.2172026-1-chris@xxxxxxxxxxxxxxxxxx (cherry picked from commit f4e9894b6952a2819937f363cd42e7cd7894a1e4) Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/i915/i915_pmu.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) --- a/drivers/gpu/drm/i915/i915_pmu.c +++ b/drivers/gpu/drm/i915/i915_pmu.c @@ -594,8 +594,10 @@ static void i915_pmu_enable(struct perf_ container_of(event->pmu, typeof(*i915), pmu.base); unsigned int bit = event_enabled_bit(event); struct i915_pmu *pmu = &i915->pmu; + intel_wakeref_t wakeref; unsigned long flags; + wakeref = intel_runtime_pm_get(&i915->runtime_pm); spin_lock_irqsave(&pmu->lock, flags); /* @@ -605,6 +607,14 @@ static void i915_pmu_enable(struct perf_ BUILD_BUG_ON(ARRAY_SIZE(pmu->enable_count) != I915_PMU_MASK_BITS); GEM_BUG_ON(bit >= ARRAY_SIZE(pmu->enable_count)); GEM_BUG_ON(pmu->enable_count[bit] == ~0); + + if (pmu->enable_count[bit] == 0 && + config_enabled_mask(I915_PMU_RC6_RESIDENCY) & BIT_ULL(bit)) { + pmu->sample[__I915_SAMPLE_RC6_LAST_REPORTED].cur = 0; + pmu->sample[__I915_SAMPLE_RC6].cur = __get_rc6(&i915->gt); + pmu->sleep_last = ktime_get(); + } + pmu->enable |= BIT_ULL(bit); pmu->enable_count[bit]++; @@ -645,6 +655,8 @@ static void i915_pmu_enable(struct perf_ * an existing non-zero value. */ local64_set(&event->hw.prev_count, __i915_pmu_event_read(event)); + + intel_runtime_pm_put(&i915->runtime_pm, wakeref); } static void i915_pmu_disable(struct perf_event *event)
