From 3033acab07f95c089fb871896406657ad4000ed6 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Fri, 28 Oct 2016 13:58:47 +0100 Subject: [PATCH] drm/i915: Queue the idling context switch after all other timelines Before suspend, we wait for the switch to the kernel context. In order for all the other context images to be complete upon suspend, that switch must be the last operation by the GPU (i.e. this idling request must not overtake any pending requests). To make this request execute last, we make it depend on every other inflight request. Signed-off-by: Chris Wilson Reviewed-by: Joonas Lahtinen Link: http://patchwork.freedesktop.org/patch/msgid/20161028125858.23563-24-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/i915_gem.c | 10 ++++++++++ drivers/gpu/drm/i915/i915_gem_context.c | 23 +++++++++++++++++------ 2 files changed, 27 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 5253602..5ea46a7 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -4362,6 +4362,15 @@ void __i915_gem_object_release_unless_active(struct drm_i915_gem_object *obj) i915_gem_object_put(obj); } +static void assert_kernel_context_is_current(struct drm_i915_private *dev_priv) +{ + struct intel_engine_cs *engine; + enum intel_engine_id id; + + for_each_engine(engine, dev_priv, id) + GEM_BUG_ON(engine->last_context != dev_priv->kernel_context); +} + int i915_gem_suspend(struct drm_device *dev) { struct drm_i915_private *dev_priv = to_i915(dev); @@ -4391,6 +4400,7 @@ int i915_gem_suspend(struct drm_device *dev) i915_gem_retire_requests(dev_priv); + assert_kernel_context_is_current(dev_priv); i915_gem_context_lost(dev_priv); mutex_unlock(&dev->struct_mutex); diff --git a/drivers/gpu/drm/i915/i915_gem_context.c b/drivers/gpu/drm/i915/i915_gem_context.c index 47e888c..a2acb8b 100644 --- a/drivers/gpu/drm/i915/i915_gem_context.c +++ b/drivers/gpu/drm/i915/i915_gem_context.c @@ -931,22 +931,33 @@ int i915_switch_context(struct drm_i915_gem_request *req) int i915_gem_switch_to_kernel_context(struct drm_i915_private *dev_priv) { struct intel_engine_cs *engine; + struct i915_gem_timeline *timeline; enum intel_engine_id id; + lockdep_assert_held(&dev_priv->drm.struct_mutex); + for_each_engine(engine, dev_priv, id) { struct drm_i915_gem_request *req; int ret; - if (engine->last_context == NULL) - continue; - - if (engine->last_context == dev_priv->kernel_context) - continue; - req = i915_gem_request_alloc(engine, dev_priv->kernel_context); if (IS_ERR(req)) return PTR_ERR(req); + /* Queue this switch after all other activity */ + list_for_each_entry(timeline, &dev_priv->gt.timelines, link) { + struct drm_i915_gem_request *prev; + struct intel_timeline *tl; + + tl = &timeline->engine[engine->id]; + prev = i915_gem_active_raw(&tl->last_request, + &dev_priv->drm.struct_mutex); + if (prev) + i915_sw_fence_await_sw_fence_gfp(&req->submit, + &prev->submit, + GFP_KERNEL); + } + ret = i915_switch_context(req); i915_add_request_no_flush(req); if (ret) -- 2.7.4