diff options
| author | Chris Wilson <chris@chris-wilson.co.uk> | 2020-12-31 09:31:49 +0000 |
|---|---|---|
| committer | Chris Wilson <chris@chris-wilson.co.uk> | 2020-12-31 15:15:05 +0000 |
| commit | 4e5c8a99e1cb701aa3ed70d9c0eb5aacd9529390 (patch) | |
| tree | 5bd5330272a99cae45965a966d6fce081a40a7cb /drivers/gpu/drm/i915/gt/intel_rps.c | |
| parent | 9c080b0f96371dceca92d67b0c50c07b479203e2 (diff) | |
drm/i915: Drop i915_request.lock requirement for intel_rps_boost()
Since we use a flag within i915_request.flags to indicate when we have
boosted the request (so that we only apply the boost) once, this can be
used as the serialisation with i915_request_retire() to avoid having to
explicitly take the i915_request.lock which is more heavily contended.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201231093149.19086-1-chris@chris-wilson.co.uk
Diffstat (limited to 'drivers/gpu/drm/i915/gt/intel_rps.c')
| -rw-r--r-- | drivers/gpu/drm/i915/gt/intel_rps.c | 25 |
1 files changed, 13 insertions, 12 deletions
diff --git a/drivers/gpu/drm/i915/gt/intel_rps.c b/drivers/gpu/drm/i915/gt/intel_rps.c index f74d5e09e176..69e1bd46cc46 100644 --- a/drivers/gpu/drm/i915/gt/intel_rps.c +++ b/drivers/gpu/drm/i915/gt/intel_rps.c @@ -862,6 +862,8 @@ void intel_rps_park(struct intel_rps *rps) { int adj; + GEM_BUG_ON(atomic_read(&rps->num_waiters)); + if (!intel_rps_clear_active(rps)) return; @@ -917,28 +919,27 @@ void intel_rps_park(struct intel_rps *rps) void intel_rps_boost(struct i915_request *rq) { - struct intel_rps *rps = &READ_ONCE(rq->engine)->gt->rps; - unsigned long flags; - - if (i915_request_signaled(rq) || !intel_rps_is_active(rps)) + if (i915_request_signaled(rq) || i915_request_has_waitboost(rq)) return; /* Serializes with i915_request_retire() */ - spin_lock_irqsave(&rq->lock, flags); - if (!i915_request_has_waitboost(rq) && - !dma_fence_is_signaled_locked(&rq->fence)) { - set_bit(I915_FENCE_FLAG_BOOST, &rq->fence.flags); + if (!test_and_set_bit(I915_FENCE_FLAG_BOOST, &rq->fence.flags)) { + struct intel_rps *rps = &READ_ONCE(rq->engine)->gt->rps; + + if (atomic_fetch_inc(&rps->num_waiters)) + return; + + if (!intel_rps_is_active(rps)) + return; GT_TRACE(rps_to_gt(rps), "boost fence:%llx:%llx\n", rq->fence.context, rq->fence.seqno); - if (!atomic_fetch_inc(&rps->num_waiters) && - READ_ONCE(rps->cur_freq) < rps->boost_freq) + if (READ_ONCE(rps->cur_freq) < rps->boost_freq) schedule_work(&rps->work); - atomic_inc(&rps->boosts); + WRITE_ONCE(rps->boosts, rps->boosts + 1); /* debug only */ } - spin_unlock_irqrestore(&rq->lock, flags); } int intel_rps_set(struct intel_rps *rps, u8 val) |