From 3a7a92aba8fb77162e1e9963360fd81fc15c39a5 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Wed, 23 Oct 2019 14:31:05 +0100 Subject: drm/i915/execlists: Force preemption If the preempted context takes too long to relinquish control, e.g. it is stuck inside a shader with arbitration disabled, evict that context with an engine reset. This ensures that preemptions are reasonably responsive, providing a tighter QoS for the more important context at the cost of flagging unresponsive contexts more frequently (i.e. instead of using an ~10s hangcheck, we now evict at ~100ms). The challenge of lies in picking a timeout that can be reasonably serviced by HW for typical workloads, balancing the existing clients against the needs for responsiveness. Note that coupled with timeslicing, this will lead to rapid GPU "hang" detection with multiple active contexts vying for GPU time. The forced preemption mechanism can be compiled out with ./scripts/config --set-val DRM_I915_PREEMPT_TIMEOUT 0 Signed-off-by: Chris Wilson Cc: Mika Kuoppala Cc: Tvrtko Ursulin Reviewed-by: Mika Kuoppala Link: https://patchwork.freedesktop.org/patch/msgid/20191023133108.21401-2-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/i915_gem.h | 14 -------------- 1 file changed, 14 deletions(-) (limited to 'drivers/gpu/drm/i915/i915_gem.h') diff --git a/drivers/gpu/drm/i915/i915_gem.h b/drivers/gpu/drm/i915/i915_gem.h index 2011f8e9a9f1..f6f9675848b8 100644 --- a/drivers/gpu/drm/i915/i915_gem.h +++ b/drivers/gpu/drm/i915/i915_gem.h @@ -112,18 +112,4 @@ static inline bool __tasklet_is_scheduled(struct tasklet_struct *t) return test_bit(TASKLET_STATE_SCHED, &t->state); } -static inline void cancel_timer(struct timer_list *t) -{ - if (!READ_ONCE(t->expires)) - return; - - del_timer(t); - WRITE_ONCE(t->expires, 0); -} - -static inline bool timer_expired(const struct timer_list *t) -{ - return READ_ONCE(t->expires) && !timer_pending(t); -} - #endif /* __I915_GEM_H__ */ -- cgit v1.2.3