[PATCH 5/7] drm/radeon: add spinlock for BO_VA status protection

[Dieter Nützel]

Am 27.11.2014 14:48, schrieb Christian König:
> From: Christian König <christian.koenig at amd.com>
> 
> Stop using the VM mutex for this
> 
> Signed-off-by: Christian König <christian.koenig at amd.com>
> ---
>  drivers/gpu/drm/radeon/radeon.h    |  3 +++
>  drivers/gpu/drm/radeon/radeon_vm.c | 36 
> ++++++++++++++++++++++++++++++------
>  2 files changed, 33 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/radeon/radeon.h 
> b/drivers/gpu/drm/radeon/radeon.h
> index da1c549..3680cf0 100644
> --- a/drivers/gpu/drm/radeon/radeon.h
> +++ b/drivers/gpu/drm/radeon/radeon.h
> @@ -929,6 +929,9 @@ struct radeon_vm {
> 
>  	struct rb_root		va;
> 
> +	/* ptotecting invalidated and freed */

protecting

> +	spinlock_t		status_lock;
> +
>  	/* BOs moved, but not yet updated in the PT */
>  	struct list_head	invalidated;
> 
> diff --git a/drivers/gpu/drm/radeon/radeon_vm.c
> b/drivers/gpu/drm/radeon/radeon_vm.c
> index 6bc3821..cde48c4 100644
> --- a/drivers/gpu/drm/radeon/radeon_vm.c
> +++ b/drivers/gpu/drm/radeon/radeon_vm.c
> @@ -487,7 +487,9 @@ int radeon_vm_bo_set_addr(struct radeon_device 
> *rdev,
>  			tmp->vm = vm;
>  			tmp->addr = bo_va->addr;
>  			tmp->bo = radeon_bo_ref(bo_va->bo);
> +			spin_lock(&vm->status_lock);
>  			list_add(&tmp->vm_status, &vm->freed);
> +			spin_unlock(&vm->status_lock);
>  		}
> 
>  		interval_tree_remove(&bo_va->it, &vm->va);
> @@ -913,7 +915,9 @@ int radeon_vm_bo_update(struct radeon_device *rdev,
>  		return -EINVAL;
>  	}
> 
> +	spin_lock(&vm->status_lock);
>  	list_del_init(&bo_va->vm_status);
> +	spin_unlock(&vm->status_lock);
> 
>  	bo_va->flags &= ~RADEON_VM_PAGE_VALID;
>  	bo_va->flags &= ~RADEON_VM_PAGE_SYSTEM;
> @@ -1028,17 +1032,25 @@ int radeon_vm_bo_update(struct radeon_device 
> *rdev,
>  int radeon_vm_clear_freed(struct radeon_device *rdev,
>  			  struct radeon_vm *vm)
>  {
> -	struct radeon_bo_va *bo_va, *tmp;
> +	struct radeon_bo_va *bo_va;
>  	int r;
> 
> -	list_for_each_entry_safe(bo_va, tmp, &vm->freed, vm_status) {
> +	spin_lock(&vm->status_lock);
> +	while (!list_empty(&vm->freed)) {
> +		bo_va = list_first_entry(&vm->freed,
> +			struct radeon_bo_va, vm_status);
> +		spin_unlock(&vm->status_lock);
> +
>  		r = radeon_vm_bo_update(rdev, bo_va, NULL);
>  		radeon_bo_unref(&bo_va->bo);
>  		radeon_fence_unref(&bo_va->last_pt_update);
>  		kfree(bo_va);
>  		if (r)
>  			return r;
> +
> +		spin_lock(&vm->status_lock);
>  	}
> +	spin_unlock(&vm->status_lock);
>  	return 0;
> 
>  }
> @@ -1057,14 +1069,23 @@ int radeon_vm_clear_freed(struct radeon_device 
> *rdev,
>  int radeon_vm_clear_invalids(struct radeon_device *rdev,
>  			     struct radeon_vm *vm)
>  {
> -	struct radeon_bo_va *bo_va, *tmp;
> +	struct radeon_bo_va *bo_va;
>  	int r;
> 
> -	list_for_each_entry_safe(bo_va, tmp, &vm->invalidated, vm_status) {
> +	spin_lock(&vm->status_lock);
> +	while (!list_empty(&vm->invalidated)) {
> +		bo_va = list_first_entry(&vm->invalidated,
> +			struct radeon_bo_va, vm_status);
> +		spin_unlock(&vm->status_lock);
> +
>  		r = radeon_vm_bo_update(rdev, bo_va, NULL);
>  		if (r)
>  			return r;
> +
> +		spin_lock(&vm->status_lock);
>  	}
> +	spin_unlock(&vm->status_lock);
> +
>  	return 0;
>  }
> 
> @@ -1087,6 +1108,7 @@ void radeon_vm_bo_rmv(struct radeon_device *rdev,
> 
>  	mutex_lock(&vm->mutex);
>  	interval_tree_remove(&bo_va->it, &vm->va);
> +	spin_lock(&vm->status_lock);
>  	list_del(&bo_va->vm_status);
> 
>  	if (bo_va->addr) {
> @@ -1096,6 +1118,7 @@ void radeon_vm_bo_rmv(struct radeon_device *rdev,
>  		radeon_fence_unref(&bo_va->last_pt_update);
>  		kfree(bo_va);
>  	}
> +	spin_unlock(&vm->status_lock);
> 
>  	mutex_unlock(&vm->mutex);
>  }
> @@ -1116,10 +1139,10 @@ void radeon_vm_bo_invalidate(struct 
> radeon_device *rdev,
> 
>  	list_for_each_entry(bo_va, &bo->va, bo_list) {
>  		if (bo_va->addr) {
> -			mutex_lock(&bo_va->vm->mutex);
> +			spin_lock(&bo_va->vm->status_lock);
>  			list_del(&bo_va->vm_status);
>  			list_add(&bo_va->vm_status, &bo_va->vm->invalidated);
> -			mutex_unlock(&bo_va->vm->mutex);
> +			spin_unlock(&bo_va->vm->status_lock);
>  		}
>  	}
>  }
> @@ -1147,6 +1170,7 @@ int radeon_vm_init(struct radeon_device *rdev,
> struct radeon_vm *vm)
>  	}
>  	mutex_init(&vm->mutex);
>  	vm->va = RB_ROOT;
> +	spin_lock_init(&vm->status_lock);
>  	INIT_LIST_HEAD(&vm->invalidated);
>  	INIT_LIST_HEAD(&vm->freed);