Since vma destruction from the vm destruction path now takes the object lock, we no longer need to take a vm reference from i915_gem_object_unbind to make sure vmas are kept alive, the required object lock taken across i915_gem_object_unbind is sufficient. Also skip retrying on I915_GEM_OBJECT_UNBIND_BARRIER, since we can't race with vm destruction anymore. Signed-off-by: Thomas Hellström <thomas.hellstrom@xxxxxxxxxxxxxxx> --- drivers/gpu/drm/i915/gem/i915_gem_domain.c | 4 +--- drivers/gpu/drm/i915/i915_drv.h | 7 +++---- drivers/gpu/drm/i915/i915_gem.c | 18 ------------------ 3 files changed, 4 insertions(+), 25 deletions(-) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_domain.c b/drivers/gpu/drm/i915/gem/i915_gem_domain.c index 1674b0c5802b..cf1f39f80603 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_domain.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_domain.c @@ -279,9 +279,7 @@ int i915_gem_object_set_cache_level(struct drm_i915_gem_object *obj, } /* The cache-level will be applied when each vma is rebound. */ - return i915_gem_object_unbind(obj, - I915_GEM_OBJECT_UNBIND_ACTIVE | - I915_GEM_OBJECT_UNBIND_BARRIER); + return i915_gem_object_unbind(obj, I915_GEM_OBJECT_UNBIND_ACTIVE); } int i915_gem_get_caching_ioctl(struct drm_device *dev, void *data, diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index c22f29c3faa0..6034e6319b6c 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -1415,10 +1415,9 @@ i915_gem_object_ggtt_pin(struct drm_i915_gem_object *obj, int i915_gem_object_unbind(struct drm_i915_gem_object *obj, unsigned long flags); #define I915_GEM_OBJECT_UNBIND_ACTIVE BIT(0) -#define I915_GEM_OBJECT_UNBIND_BARRIER BIT(1) -#define I915_GEM_OBJECT_UNBIND_TEST BIT(2) -#define I915_GEM_OBJECT_UNBIND_VM_TRYLOCK BIT(3) -#define I915_GEM_OBJECT_UNBIND_ASYNC BIT(4) +#define I915_GEM_OBJECT_UNBIND_TEST BIT(1) +#define I915_GEM_OBJECT_UNBIND_VM_TRYLOCK BIT(2) +#define I915_GEM_OBJECT_UNBIND_ASYNC BIT(3) void i915_gem_runtime_suspend(struct drm_i915_private *dev_priv); diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 702e5b89be22..df16a5e8f5c7 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -137,7 +137,6 @@ int i915_gem_object_unbind(struct drm_i915_gem_object *obj, */ wakeref = intel_runtime_pm_get(rpm); -try_again: ret = 0; spin_lock(&obj->vma.lock); while (!ret && (vma = list_first_entry_or_null(&obj->vma.list, @@ -152,17 +151,6 @@ int i915_gem_object_unbind(struct drm_i915_gem_object *obj, break; } - /* - * Requiring the vm destructor to take the object lock - * before destroying a vma would help us eliminate the - * i915_vm_tryget() here, AND thus also the barrier stuff - * at the end. That's an easy fix, but sleeping locks in - * a kthread should generally be avoided. - */ - ret = -EAGAIN; - if (!i915_vm_tryget(vma->vm)) - break; - spin_unlock(&obj->vma.lock); /* @@ -189,17 +177,11 @@ int i915_gem_object_unbind(struct drm_i915_gem_object *obj, } } - i915_vm_put(vma->vm); spin_lock(&obj->vma.lock); } list_splice_init(&still_in_list, &obj->vma.list); spin_unlock(&obj->vma.lock); - if (ret == -EAGAIN && flags & I915_GEM_OBJECT_UNBIND_BARRIER) { - rcu_barrier(); /* flush the i915_vm_release() */ - goto try_again; - } - intel_runtime_pm_put(rpm, wakeref); return ret; -- 2.36.1