Hardware can't handle seqno wrapping so all previous requests need to be retired before seqno can wrap. As this can fail, make seqno allocation explicit by introducing i915_gem_alloc_seqno()
Signed-off-by: Mika Kuoppala <[email protected]> --- drivers/gpu/drm/i915/i915_drv.h | 1 + drivers/gpu/drm/i915/i915_gem.c | 51 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 52 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index f511fa2..598f3b8 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -1387,6 +1387,7 @@ i915_seqno_passed(uint32_t seq1, uint32_t seq2) return (int32_t)(seq1 - seq2) >= 0; } +int i915_gem_alloc_seqno(struct intel_ring_buffer *ring, u32 *seqno); u32 i915_gem_next_request_seqno(struct intel_ring_buffer *ring); int __must_check i915_gem_object_get_fence(struct drm_i915_gem_object *obj); diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 7e17382..a637d5d 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -1933,6 +1933,34 @@ i915_gem_object_move_to_inactive(struct drm_i915_gem_object *obj) WARN_ON(i915_verify_lists(dev)); } +static int +i915_gem_handle_seqno_wrap(struct drm_device *dev) +{ + drm_i915_private_t *dev_priv = dev->dev_private; + struct intel_ring_buffer *ring; + int ret; + int i; + + /* The GPU can not handle its semaphore value wrapping, + + * so every billion or so execbuffers, we need to stall + * the GPU in order to reset the counters. + */ + + ret = i915_gpu_idle(dev); + if (ret) + return ret; + + i915_gem_retire_requests(dev); + + for_each_ring(ring, dev_priv, i) { + int j; + for (j = 0; j < ARRAY_SIZE(ring->sync_seqno); j++) + BUG_ON(ring->sync_seqno[j]); + } + + return 0; +} + static u32 i915_gem_get_seqno(struct drm_device *dev) { @@ -1956,6 +1984,29 @@ i915_gem_next_request_seqno(struct intel_ring_buffer *ring) } int +i915_gem_alloc_seqno(struct intel_ring_buffer *ring, u32 *seqno) +{ + drm_i915_private_t *dev_priv = ring->dev->dev_private; + int ret; + + /* reserve 0 for non-seqno */ + if (unlikely(dev_priv->next_seqno == ~0)) { + ret = i915_gem_handle_seqno_wrap(ring->dev); + if (ret) + return ret; + + dev_priv->next_seqno = 1; + } + + dev_priv->next_seqno++; + + if (seqno) + *seqno = i915_gem_next_request_seqno(ring); + + return 0; +} + +int i915_add_request(struct intel_ring_buffer *ring, struct drm_file *file, u32 *out_seqno) -- 1.7.9.5 _______________________________________________ Intel-gfx mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/intel-gfx
