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.dan...@intel.com> --- drivers/gpu/drm/i915/i915_gem_context.c | 12 +++++++---- drivers/gpu/drm/i915/intel_lrc.c | 34 +++++++++++++++++++++++++++++++ drivers/gpu/drm/i915/intel_lrc.h | 2 ++ 3 files changed, 44 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem_context.c b/drivers/gpu/drm/i915/i915_gem_context.c index 8603bf4..70346b0 100644 --- a/drivers/gpu/drm/i915/i915_gem_context.c +++ b/drivers/gpu/drm/i915/i915_gem_context.c @@ -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]; diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c index aafcef3..1946bb9 100644 --- a/drivers/gpu/drm/i915/intel_lrc.c +++ b/drivers/gpu/drm/i915/intel_lrc.c @@ -1950,3 +1950,37 @@ error_unpin_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; + if (ctx_obj) { + struct intel_ringbuffer *ringbuf = + ctx->engine[ring->id].ringbuf; + uint32_t *reg_state; + struct page *page; + + 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; + } + } +} diff --git a/drivers/gpu/drm/i915/intel_lrc.h b/drivers/gpu/drm/i915/intel_lrc.h index f635735..5dd0eca 100644 --- a/drivers/gpu/drm/i915/intel_lrc.h +++ b/drivers/gpu/drm/i915/intel_lrc.h @@ -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); -- 1.7.9.5 _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
