diff options
| author | Tvrtko Ursulin <tvrtko.ursulin@intel.com> | 2023-05-19 08:49:44 -0700 |
|---|---|---|
| committer | Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com> | 2023-05-22 11:07:51 -0700 |
| commit | b319cc594e666061b22331da654606b92730343a (patch) | |
| tree | 3b7f24210fe0a8b500d35b2568da1a21d21b312d | |
| parent | da5d51672874936c08810e63d6dfc670263d5e15 (diff) | |
drm/i915/pmu: Add reference counting to the sampling timer
We do not want to have timers per tile and waste CPU cycles and energy via
multiple wake-up sources, for a relatively un-important task of PMU
sampling, so keeping a single timer works well. But we also do not want
the first GT which goes idle to turn off the timer.
Add some reference counting, via a mask of unparked GTs, to solve this.
v2: Drop the check for unparked in i915_sample (Ashutosh)
v3: Revert v2 (Tvrtko)
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Reviewed-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230519154946.3751971-6-umesh.nerlige.ramappa@intel.com
| -rw-r--r-- | drivers/gpu/drm/i915/i915_pmu.c | 12 | ||||
| -rw-r--r-- | drivers/gpu/drm/i915/i915_pmu.h | 4 |
2 files changed, 14 insertions, 2 deletions
diff --git a/drivers/gpu/drm/i915/i915_pmu.c b/drivers/gpu/drm/i915/i915_pmu.c index 890693fdaf9e..ecb57a94143e 100644 --- a/drivers/gpu/drm/i915/i915_pmu.c +++ b/drivers/gpu/drm/i915/i915_pmu.c @@ -262,7 +262,9 @@ void i915_pmu_gt_parked(struct intel_gt *gt) * Signal sampling timer to stop if only engine events are enabled and * GPU went idle. */ - pmu->timer_enabled = pmu_needs_timer(pmu, false); + pmu->unparked &= ~BIT(gt->info.id); + if (pmu->unparked == 0) + pmu->timer_enabled = pmu_needs_timer(pmu, false); spin_unlock_irq(&pmu->lock); } @@ -279,7 +281,10 @@ void i915_pmu_gt_unparked(struct intel_gt *gt) /* * Re-enable sampling timer when GPU goes active. */ - __i915_pmu_maybe_start_timer(pmu); + if (pmu->unparked == 0) + __i915_pmu_maybe_start_timer(pmu); + + pmu->unparked |= BIT(gt->info.id); spin_unlock_irq(&pmu->lock); } @@ -449,6 +454,9 @@ static enum hrtimer_restart i915_sample(struct hrtimer *hrtimer) */ for_each_gt(gt, i915, i) { + if (!(pmu->unparked & BIT(i))) + continue; + engines_sample(gt, period_ns); if (i == 0) /* FIXME */ diff --git a/drivers/gpu/drm/i915/i915_pmu.h b/drivers/gpu/drm/i915/i915_pmu.h index a686fd7ccedf..3a811266ac6a 100644 --- a/drivers/gpu/drm/i915/i915_pmu.h +++ b/drivers/gpu/drm/i915/i915_pmu.h @@ -77,6 +77,10 @@ struct i915_pmu { */ spinlock_t lock; /** + * @unparked: GT unparked mask. + */ + unsigned int unparked; + /** * @timer: Timer for internal i915 PMU sampling. */ struct hrtimer timer; |