local_bh_disable();
i915_sw_fence_commit(&request->submit);
local_bh_enable(); /* Kick the execlists tasklet if just scheduled */
+
+ /*
+ * In typical scenarios, we do not expect the previous request on
+ * the timeline to be still tracked by timeline->last_request if it
+ * has been completed. If the completed request is still here, that
+ * implies that request retirement is a long way behind submission,
+ * suggesting that we haven't been retiring frequently enough from
+ * the combination of retire-before-alloc, waiters and the background
+ * retirement worker. So if the last request on this timeline was
+ * already completed, do a catch up pass, flushing the retirement queue
+ * up to this client. Since we have now moved the heaviest operations
+ * during retirement onto secondary workers, such as freeing objects
+ * or contexts, retiring a bunch of requests is mostly list management
+ * (and cache misses), and so we should not be overly penalizing this
+ * client by performing excess work, though we may still performing
+ * work on behalf of others -- but instead we should benefit from
+ * improved resource management. (Well, that's the theory at least.)
+ */
+ if (prev && i915_gem_request_completed(prev))
+ i915_gem_request_retire_upto(prev);
}
static unsigned long local_clock_us(unsigned int *cpu)