drm/i915: Set sync_seqno properly after seqno wrap

i915_gem_handle_seqno_wrap() will zero all sync_seqnos but as the
wrap can happen inside ring->sync_to(), pre wrap seqno was
carried over and overwrote the zeroed sync_seqno.

When wrap is handled, all outstanding requests will be retired and
objects moved to inactive queue, causing their last_read_seqno to be zero.
Use this to update the sync_seqno correctly.

RING_SYNC registers after wrap will contain pre wrap values which
are >= seqno. So injecting the semaphore wait into ring completes
immediately.

Original idea for using last_read_seqno from Chris Wilson.

Signed-off-by: Mika Kuoppala <[email protected]>
Reviewed-by: Chris Wilson <[email protected]>
Signed-off-by: Daniel Vetter <[email protected]>

0 files changed, 0 insertions, 0 deletions