diff options
| author | Mika Kuoppala <mika.kuoppala@linux.intel.com> | 2012-12-10 15:41:48 +0200 |
|---|---|---|
| committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2012-12-11 13:32:26 +0100 |
| commit | f72b3435c1a75406d82d6e252bb78f009efd4bd9 (patch) | |
| tree | 5b9e854dc74ca4d52374cd6e7e816312c6daca31 /drivers/gpu/drm/i915/intel_ringbuffer.c | |
| parent | 3ac18232946aacf0a9807c3143f8449ed4aa68f4 (diff) | |
drm/i915: Don't emit semaphore wait if wrap happened
If wrap just happened we need to prevent emitting waits for
pre wrap values. Detect this and emit no-ops instead.
v2: Use olr > seqno to detect wrap instead of *seqno == 0
as suggested by Chris Wilson.
v3: Use last used seqno to detect the wraparound. From
Chris Wilson
v4: Fixed unnecessary last_seqno assigment
References: https://bugs.freedesktop.org/show_bug.cgi?id=57967
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Diffstat (limited to 'drivers/gpu/drm/i915/intel_ringbuffer.c')
| -rw-r--r-- | drivers/gpu/drm/i915/intel_ringbuffer.c | 26 |
1 files changed, 21 insertions, 5 deletions
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c index 0d03dc649c5..69bbe7bb9f6 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.c +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c @@ -596,6 +596,13 @@ gen6_add_request(struct intel_ring_buffer *ring) return 0; } +static inline bool i915_gem_has_seqno_wrapped(struct drm_device *dev, + u32 seqno) +{ + struct drm_i915_private *dev_priv = dev->dev_private; + return dev_priv->last_seqno < seqno; +} + /** * intel_ring_sync - sync the waiter to the signaller on seqno * @@ -626,11 +633,20 @@ gen6_ring_sync(struct intel_ring_buffer *waiter, if (ret) return ret; - intel_ring_emit(waiter, - dw1 | signaller->semaphore_register[waiter->id]); - intel_ring_emit(waiter, seqno); - intel_ring_emit(waiter, 0); - intel_ring_emit(waiter, MI_NOOP); + /* If seqno wrap happened, omit the wait with no-ops */ + if (likely(!i915_gem_has_seqno_wrapped(waiter->dev, seqno))) { + intel_ring_emit(waiter, + dw1 | + signaller->semaphore_register[waiter->id]); + intel_ring_emit(waiter, seqno); + intel_ring_emit(waiter, 0); + intel_ring_emit(waiter, MI_NOOP); + } else { + intel_ring_emit(waiter, MI_NOOP); + intel_ring_emit(waiter, MI_NOOP); + intel_ring_emit(waiter, MI_NOOP); + intel_ring_emit(waiter, MI_NOOP); + } intel_ring_advance(waiter); return 0; |