drm/i915: Reset logical ring contexts' head and tail during GPU reset

Work was getting left behind in LRC contexts during reset.  This causes a hang
if the GPU is reset when HEAD==TAIL because the context's ringbuffer head and
tail don't get reset and retiring a request doesn't alter them, so the ring
still appears full.

Added a function intel_lr_context_reset() to reset head and tail on a LRC and
its ringbuffer.

Call intel_lr_context_reset() for each context in i915_gem_context_reset() when
in execlists mode.

Testcase: igt/pm_rps --run-subtest reset #bdw
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=88096
Signed-off-by: Thomas Daniel <thomas.daniel@intel.com>
Reviewed-by: Dave Gordon <david.s.gordon@intel.com>
[danvet: Flatten control flow in the lrc reset code a notch.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This commit is contained in:
Thomas Daniel 2015-02-16 16:12:53 +00:00 committed by Daniel Vetter
parent b766879106
commit 3e5b6f05a2
3 changed files with 45 additions and 4 deletions

View File

@ -296,11 +296,15 @@ void i915_gem_context_reset(struct drm_device *dev)
struct drm_i915_private *dev_priv = dev->dev_private;
int i;
/* In execlists mode we will unreference the context when the execlist
* queue is cleared and the requests destroyed.
*/
if (i915.enable_execlists)
if (i915.enable_execlists) {
struct intel_context *ctx;
list_for_each_entry(ctx, &dev_priv->context_list, link) {
intel_lr_context_reset(dev, ctx);
}
return;
}
for (i = 0; i < I915_NUM_RINGS; i++) {
struct intel_engine_cs *ring = &dev_priv->ring[i];

View File

@ -1991,3 +1991,38 @@ int intel_lr_context_deferred_create(struct intel_context *ctx,
drm_gem_object_unreference(&ctx_obj->base);
return ret;
}
void intel_lr_context_reset(struct drm_device *dev,
struct intel_context *ctx)
{
struct drm_i915_private *dev_priv = dev->dev_private;
struct intel_engine_cs *ring;
int i;
for_each_ring(ring, dev_priv, i) {
struct drm_i915_gem_object *ctx_obj =
ctx->engine[ring->id].state;
struct intel_ringbuffer *ringbuf =
ctx->engine[ring->id].ringbuf;
uint32_t *reg_state;
struct page *page;
if (!ctx_obj)
continue;
if (i915_gem_object_get_pages(ctx_obj)) {
WARN(1, "Failed get_pages for context obj\n");
continue;
}
page = i915_gem_object_get_page(ctx_obj, 1);
reg_state = kmap_atomic(page);
reg_state[CTX_RING_HEAD+1] = 0;
reg_state[CTX_RING_TAIL+1] = 0;
kunmap_atomic(reg_state);
ringbuf->head = 0;
ringbuf->tail = 0;
}
}

View File

@ -73,6 +73,8 @@ int intel_lr_context_deferred_create(struct intel_context *ctx,
struct intel_engine_cs *ring);
void intel_lr_context_unpin(struct intel_engine_cs *ring,
struct intel_context *ctx);
void intel_lr_context_reset(struct drm_device *dev,
struct intel_context *ctx);
/* Execlists */
int intel_sanitize_enable_execlists(struct drm_device *dev, int enable_execlists);