drm/i915: Wait upon the last request seqno, rather than a future seqno

In commit 69c2fc8913
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Fri Jul 20 12:41:03 2012 +0100

    drm/i915: Remove the per-ring write list

the explicit flush was removed from i915_ring_idle(). However, we
continued to wait upon the next seqno which now did not correspond to
any request (except for the unusual condition of a failure to queue a
request after execbuffer) and so would wait indefinitely.

This has an important side-effect that i915_gpu_idle() does not cause
the seqno to be incremented. This is vital if we are to be able to idle
the GPU to handle seqno wraparound, as in subsequent patches.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This commit is contained in:
Chris Wilson 2012-11-22 13:07:20 +00:00 committed by Daniel Vetter
parent 4f1ba0f83a
commit b5d177946a

View File

@ -2462,10 +2462,29 @@ i915_gem_object_unbind(struct drm_i915_gem_object *obj)
static int i915_ring_idle(struct intel_ring_buffer *ring)
{
if (list_empty(&ring->active_list))
u32 seqno;
int ret;
/* We need to add any requests required to flush the objects */
if (!list_empty(&ring->active_list)) {
seqno = list_entry(ring->active_list.prev,
struct drm_i915_gem_object,
ring_list)->last_read_seqno;
ret = i915_gem_check_olr(ring, seqno);
if (ret)
return ret;
}
/* Wait upon the last request to be completed */
if (list_empty(&ring->request_list))
return 0;
return i915_wait_seqno(ring, i915_gem_next_request_seqno(ring));
seqno = list_entry(ring->request_list.prev,
struct drm_i915_gem_request,
list)->seqno;
return i915_wait_seqno(ring, seqno);
}
int i915_gpu_idle(struct drm_device *dev)