Commit 0bc71adc authored by Philip Yang's avatar Philip Yang Committed by Alex Deucher
Browse files

drm/amdgpu: Drop eviction lock when allocating PT BO 



Re-take the eviction lock immediately again after the allocation is
completed, to fix circular locking warning with drm_buddy allocator.

Move amdgpu_vm_eviction_lock/unlock/trylock to amdgpu_vm.h as they are
called from multiple files.

Signed-off-by: default avatarPhilip Yang <Philip.Yang@amd.com>
Reviewed-by: default avatarChristian König <christian.koenig@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent c70e2166

drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c

+0 −26
Original line number Diff line number Diff line
@@ -143,32 +143,6 @@ int amdgpu_vm_set_pasid(struct amdgpu_device *adev, struct amdgpu_vm *vm, 
	return 0;

}



/*

 * vm eviction_lock can be taken in MMU notifiers. Make sure no reclaim-FS

 * happens while holding this lock anywhere to prevent deadlocks when

 * an MMU notifier runs in reclaim-FS context.

 */

static inline void amdgpu_vm_eviction_lock(struct amdgpu_vm *vm)

{

	mutex_lock(&vm->eviction_lock);

	vm->saved_flags = memalloc_noreclaim_save();

}



static inline int amdgpu_vm_eviction_trylock(struct amdgpu_vm *vm)

{

	if (mutex_trylock(&vm->eviction_lock)) {

		vm->saved_flags = memalloc_noreclaim_save();

		return 1;

	}

	return 0;

}



static inline void amdgpu_vm_eviction_unlock(struct amdgpu_vm *vm)

{

	memalloc_noreclaim_restore(vm->saved_flags);

	mutex_unlock(&vm->eviction_lock);

}



/**

 * amdgpu_vm_bo_evicted - vm_bo is evicted

 *

drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h

+26 −0
Original line number Diff line number Diff line
@@ -510,4 +510,30 @@ static inline uint64_t amdgpu_vm_tlb_seq(struct amdgpu_vm *vm) 
	return atomic64_read(&vm->tlb_seq);

}



/*

 * vm eviction_lock can be taken in MMU notifiers. Make sure no reclaim-FS

 * happens while holding this lock anywhere to prevent deadlocks when

 * an MMU notifier runs in reclaim-FS context.

 */

static inline void amdgpu_vm_eviction_lock(struct amdgpu_vm *vm)

{

	mutex_lock(&vm->eviction_lock);

	vm->saved_flags = memalloc_noreclaim_save();

}



static inline bool amdgpu_vm_eviction_trylock(struct amdgpu_vm *vm)

{

	if (mutex_trylock(&vm->eviction_lock)) {

		vm->saved_flags = memalloc_noreclaim_save();

		return true;

	}

	return false;

}



static inline void amdgpu_vm_eviction_unlock(struct amdgpu_vm *vm)

{

	memalloc_noreclaim_restore(vm->saved_flags);

	mutex_unlock(&vm->eviction_lock);

}



#endif

drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c

+2 −0
Original line number Diff line number Diff line
@@ -597,7 +597,9 @@ static int amdgpu_vm_pt_alloc(struct amdgpu_device *adev, 
	if (entry->bo)

		return 0;



	amdgpu_vm_eviction_unlock(vm);

	r = amdgpu_vm_pt_create(adev, vm, cursor->level, immediate, &pt);

	amdgpu_vm_eviction_lock(vm);

	if (r)

		return r;