Re: [PATCH 3/3] i915/guc: Accumulate active runtime on gt reset

[John Harrison]

On 11/27/2024 09:40, Umesh Nerlige Ramappa wrote:

On gt reset, if a context is running, then accumulate it's active time
into the busyness counter since there will be no chance for the context
to switch out and update it's run time.

v2: Move comment right above the if (John)

Fixes: 77cdd054dd2c ("drm/i915/pmu: Connect engine busyness stats from GuC to 
pmu")
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.rama...@intel.com>

Reviewed-by: John Harrison <john.c.harri...@intel.com>

---
  drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c | 15 ++++++++++++++-
  1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c 
b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
index 56be9f385270..2876024041a7 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c
@@ -1449,8 +1449,21 @@ static void __reset_guc_busyness_stats(struct intel_guc 
*guc)

guc_update_pm_timestamp(guc, &unused);

        for_each_engine(engine, gt, id) {
+               struct intel_engine_guc_stats *stats = &engine->stats.guc;
+
                guc_update_engine_gt_clks(engine);
-               engine->stats.guc.prev_total = 0;
+
+               /*
+                * If resetting a running context, accumulate the active
+                * time as well since there will be no context switch.
+                */
+               if (stats->running) {
+                       u64 clk = guc->timestamp.gt_stamp - stats->start_gt_clk;
+
+                       stats->total_gt_clks += clk;
+               }
+               stats->prev_total = 0;
+               stats->running = 0;
        }

spin_unlock_irqrestore(&guc->timestamp.lock, flags);