drm/amdgpu: Simplify eviction fence handling

Temporarily removing eviction fences to avoid triggering them by
accident is no longer necessary due to the fence_owner logic in
amdgpu_sync_resv.

As a result the ef_list usage of amdgpu_amdkfd_remove_eviction_fence
and amdgpu_amdkfd_add_eviction_fence are no longer needed.

Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Acked-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Harish Kasiviswanathan <Harish.Kasiviswanathan@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
index 44a1581..1921dec 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
@@ -204,38 +204,25 @@ void amdgpu_amdkfd_unreserve_memory_limit(struct amdgpu_bo *bo)
 }
 
 
-/* amdgpu_amdkfd_remove_eviction_fence - Removes eviction fence(s) from BO's
+/* amdgpu_amdkfd_remove_eviction_fence - Removes eviction fence from BO's
  *  reservation object.
  *
  * @bo: [IN] Remove eviction fence(s) from this BO
- * @ef: [IN] If ef is specified, then this eviction fence is removed if it
+ * @ef: [IN] This eviction fence is removed if it
  *  is present in the shared list.
- * @ef_list: [OUT] Returns list of eviction fences. These fences are removed
- *  from BO's reservation object shared list.
- * @ef_count: [OUT] Number of fences in ef_list.
  *
- * NOTE: If called with ef_list, then amdgpu_amdkfd_add_eviction_fence must be
- *  called to restore the eviction fences and to avoid memory leak. This is
- *  useful for shared BOs.
  * NOTE: Must be called with BO reserved i.e. bo->tbo.resv->lock held.
  */
 static int amdgpu_amdkfd_remove_eviction_fence(struct amdgpu_bo *bo,
-                                       struct amdgpu_amdkfd_fence *ef,
-                                       struct amdgpu_amdkfd_fence ***ef_list,
-                                       unsigned int *ef_count)
+                                       struct amdgpu_amdkfd_fence *ef)
 {
        struct reservation_object *resv = bo->tbo.resv;
        struct reservation_object_list *old, *new;
        unsigned int i, j, k;
 
-       if (!ef && !ef_list)
+       if (!ef)
                return -EINVAL;
 
-       if (ef_list) {
-               *ef_list = NULL;
-               *ef_count = 0;
-       }
-
        old = reservation_object_get_list(resv);
        if (!old)
                return 0;
@@ -254,8 +241,7 @@ static int amdgpu_amdkfd_remove_eviction_fence(struct amdgpu_bo *bo,
                f = rcu_dereference_protected(old->shared[i],
                                              reservation_object_held(resv));
 
-               if ((ef && f->context == ef->base.context) ||
-                   (!ef && to_amdgpu_amdkfd_fence(f)))
+               if (f->context == ef->base.context)
                        RCU_INIT_POINTER(new->shared[--j], f);
                else
                        RCU_INIT_POINTER(new->shared[k++], f);
@@ -263,21 +249,6 @@ static int amdgpu_amdkfd_remove_eviction_fence(struct amdgpu_bo *bo,
        new->shared_max = old->shared_max;
        new->shared_count = k;
 
-       if (!ef) {
-               unsigned int count = old->shared_count - j;
-
-               /* Alloc memory for count number of eviction fence pointers.
-                * Fill the ef_list array and ef_count
-                */
-               *ef_list = kcalloc(count, sizeof(**ef_list), GFP_KERNEL);
-               *ef_count = count;
-
-               if (!*ef_list) {
-                       kfree(new);
-                       return -ENOMEM;
-               }
-       }
-
        /* Install the new fence list, seqcount provides the barriers */
        preempt_disable();
        write_seqcount_begin(&resv->seq);
@@ -291,46 +262,13 @@ static int amdgpu_amdkfd_remove_eviction_fence(struct amdgpu_bo *bo,
 
                f = rcu_dereference_protected(new->shared[i],
                                              reservation_object_held(resv));
-               if (!ef)
-                       (*ef_list)[k++] = to_amdgpu_amdkfd_fence(f);
-               else
-                       dma_fence_put(f);
+               dma_fence_put(f);
        }
        kfree_rcu(old, rcu);
 
        return 0;
 }
 
-/* amdgpu_amdkfd_add_eviction_fence - Adds eviction fence(s) back into BO's
- *  reservation object.
- *
- * @bo: [IN] Add eviction fences to this BO
- * @ef_list: [IN] List of eviction fences to be added
- * @ef_count: [IN] Number of fences in ef_list.
- *
- * NOTE: Must call amdgpu_amdkfd_remove_eviction_fence before calling this
- *  function.
- */
-static void amdgpu_amdkfd_add_eviction_fence(struct amdgpu_bo *bo,
-                               struct amdgpu_amdkfd_fence **ef_list,
-                               unsigned int ef_count)
-{
-       int i;
-
-       if (!ef_list || !ef_count)
-               return;
-
-       for (i = 0; i < ef_count; i++) {
-               amdgpu_bo_fence(bo, &ef_list[i]->base, true);
-               /* Re-adding the fence takes an additional reference. Drop that
-                * reference.
-                */
-               dma_fence_put(&ef_list[i]->base);
-       }
-
-       kfree(ef_list);
-}
-
 static int amdgpu_amdkfd_bo_validate(struct amdgpu_bo *bo, uint32_t domain,
                                     bool wait)
 {
@@ -346,18 +284,8 @@ static int amdgpu_amdkfd_bo_validate(struct amdgpu_bo *bo, uint32_t domain,
        ret = ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
        if (ret)
                goto validate_fail;
-       if (wait) {
-               struct amdgpu_amdkfd_fence **ef_list;
-               unsigned int ef_count;
-
-               ret = amdgpu_amdkfd_remove_eviction_fence(bo, NULL, &ef_list,
-                                                         &ef_count);
-               if (ret)
-                       goto validate_fail;
-
+       if (wait)
                amdgpu_bo_sync_wait(bo, AMDGPU_FENCE_OWNER_KFD, false);
-               amdgpu_amdkfd_add_eviction_fence(bo, ef_list, ef_count);
-       }
 
 validate_fail:
        return ret;
@@ -444,7 +372,6 @@ static int add_bo_to_vm(struct amdgpu_device *adev, struct kgd_mem *mem,
 {
        int ret;
        struct kfd_bo_va_list *bo_va_entry;
-       struct amdgpu_bo *pd = vm->root.base.bo;
        struct amdgpu_bo *bo = mem->bo;
        uint64_t va = mem->va;
        struct list_head *list_bo_va = &mem->bo_va_list;
@@ -484,14 +411,8 @@ static int add_bo_to_vm(struct amdgpu_device *adev, struct kgd_mem *mem,
                *p_bo_va_entry = bo_va_entry;
 
        /* Allocate new page tables if needed and validate
-        * them. Clearing of new page tables and validate need to wait
-        * on move fences. We don't want that to trigger the eviction
-        * fence, so remove it temporarily.
+        * them.
         */
-       amdgpu_amdkfd_remove_eviction_fence(pd,
-                                       vm->process_info->eviction_fence,
-                                       NULL, NULL);
-
        ret = amdgpu_vm_alloc_pts(adev, vm, va, amdgpu_bo_size(bo));
        if (ret) {
                pr_err("Failed to allocate pts, err=%d\n", ret);
@@ -504,13 +425,9 @@ static int add_bo_to_vm(struct amdgpu_device *adev, struct kgd_mem *mem,
                goto err_alloc_pts;
        }
 
-       /* Add the eviction fence back */
-       amdgpu_bo_fence(pd, &vm->process_info->eviction_fence->base, true);
-
        return 0;
 
 err_alloc_pts:
-       amdgpu_bo_fence(pd, &vm->process_info->eviction_fence->base, true);
        amdgpu_vm_bo_rmv(adev, bo_va_entry->bo_va);
        list_del(&bo_va_entry->bo_list);
 err_vmadd:
@@ -809,24 +726,11 @@ static int unmap_bo_from_gpuvm(struct amdgpu_device *adev,
 {
        struct amdgpu_bo_va *bo_va = entry->bo_va;
        struct amdgpu_vm *vm = bo_va->base.vm;
-       struct amdgpu_bo *pd = vm->root.base.bo;
 
-       /* Remove eviction fence from PD (and thereby from PTs too as
-        * they share the resv. object). Otherwise during PT update
-        * job (see amdgpu_vm_bo_update_mapping), eviction fence would
-        * get added to job->sync object and job execution would
-        * trigger the eviction fence.
-        */
-       amdgpu_amdkfd_remove_eviction_fence(pd,
-                                           vm->process_info->eviction_fence,
-                                           NULL, NULL);
        amdgpu_vm_bo_unmap(adev, bo_va, entry->va);
 
        amdgpu_vm_clear_freed(adev, vm, &bo_va->last_pt_update);
 
-       /* Add the eviction fence back */
-       amdgpu_bo_fence(pd, &vm->process_info->eviction_fence->base, true);
-
        amdgpu_sync_fence(NULL, sync, bo_va->last_pt_update, false);
 
        return 0;
@@ -1389,8 +1293,7 @@ int amdgpu_amdkfd_gpuvm_free_memory_of_gpu(
         * attached
         */
        amdgpu_amdkfd_remove_eviction_fence(mem->bo,
-                                       process_info->eviction_fence,
-                                       NULL, NULL);
+                                       process_info->eviction_fence);
        pr_debug("Release VA 0x%llx - 0x%llx\n", mem->va,
                mem->va + bo_size * (1 + mem->aql_queue));
 
@@ -1617,8 +1520,7 @@ int amdgpu_amdkfd_gpuvm_unmap_memory_from_gpu(
        if (mem->mapped_to_gpu_memory == 0 &&
            !amdgpu_ttm_tt_get_usermm(mem->bo->tbo.ttm) && !mem->bo->pin_count)
                amdgpu_amdkfd_remove_eviction_fence(mem->bo,
-                                               process_info->eviction_fence,
-                                                   NULL, NULL);
+                                               process_info->eviction_fence);
 
 unreserve_out:
        unreserve_bo_and_vms(&ctx, false, false);
@@ -1679,7 +1581,7 @@ int amdgpu_amdkfd_gpuvm_map_gtt_bo_to_kernel(struct kgd_dev *kgd,
        }
 
        amdgpu_amdkfd_remove_eviction_fence(
-               bo, mem->process_info->eviction_fence, NULL, NULL);
+               bo, mem->process_info->eviction_fence);
        list_del_init(&mem->validate_list.head);
 
        if (size)
@@ -1945,16 +1847,6 @@ static int validate_invalid_user_pages(struct amdkfd_process_info *process_info)
 
        amdgpu_sync_create(&sync);
 
-       /* Avoid triggering eviction fences when unmapping invalid
-        * userptr BOs (waits for all fences, doesn't use
-        * FENCE_OWNER_VM)
-        */
-       list_for_each_entry(peer_vm, &process_info->vm_list_head,
-                           vm_list_node)
-               amdgpu_amdkfd_remove_eviction_fence(peer_vm->root.base.bo,
-                                               process_info->eviction_fence,
-                                               NULL, NULL);
-
        ret = process_validate_vms(process_info);
        if (ret)
                goto unreserve_out;
@@ -2015,10 +1907,6 @@ static int validate_invalid_user_pages(struct amdkfd_process_info *process_info)
        ret = process_update_pds(process_info, &sync);
 
 unreserve_out:
-       list_for_each_entry(peer_vm, &process_info->vm_list_head,
-                           vm_list_node)
-               amdgpu_bo_fence(peer_vm->root.base.bo,
-                               &process_info->eviction_fence->base, true);
        ttm_eu_backoff_reservation(&ticket, &resv_list);
        amdgpu_sync_wait(&sync, false);
        amdgpu_sync_free(&sync);