[PATCH 5/5] drm/amdgpu: use drm_exec during BO validation

[Christian König]

This allows to detect deadlocks happening because of resource
constraints.

Especially submissions which want to use all of GDS doesn't result in
sporadic -ENOMEM any more.

Signed-off-by: Christian König <christian.koenig at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c | 86 ++++++++++++++------------
 1 file changed, 46 insertions(+), 40 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
index ec888fc6ead8..ff532c8b7a62 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
@@ -782,7 +782,7 @@ static int amdgpu_cs_bo_validate(void *param, struct amdgpu_bo *bo)
 	struct ttm_operation_ctx ctx = {
 		.interruptible = true,
 		.no_wait_gpu = false,
-		.resv = bo->tbo.base.resv
+		.exec = &p->exec,
 	};
 	uint32_t domain;
 	int r;
@@ -834,7 +834,10 @@ static int amdgpu_cs_parser_bos(struct amdgpu_cs_parser *p,
 				union drm_amdgpu_cs *cs)
 {
 	struct amdgpu_fpriv *fpriv = p->filp->driver_priv;
-	struct ttm_operation_ctx ctx = { true, false };
+	struct ttm_operation_ctx ctx = {
+		.interruptible =true,
+		.exec = &p->exec
+	};
 	struct amdgpu_vm *vm = &fpriv->vm;
 	struct amdgpu_bo_list_entry *e;
 	struct drm_gem_object *obj;
@@ -919,50 +922,56 @@ static int amdgpu_cs_parser_bos(struct amdgpu_cs_parser *p,
 			if (unlikely(r))
 				goto out_free_user_pages;
 		}
-	}
-
-	amdgpu_bo_list_for_each_userptr_entry(e, p->bo_list) {
-		struct mm_struct *usermm;
 
-		usermm = amdgpu_ttm_tt_get_usermm(e->bo->tbo.ttm);
-		if (usermm && usermm != current->mm) {
-			r = -EPERM;
-			goto out_free_user_pages;
-		}
+		amdgpu_bo_list_for_each_userptr_entry(e, p->bo_list) {
+			struct mm_struct *usermm;
 
-		if (amdgpu_ttm_tt_is_userptr(e->bo->tbo.ttm) &&
-		    e->user_invalidated && e->user_pages) {
-			amdgpu_bo_placement_from_domain(e->bo,
-							AMDGPU_GEM_DOMAIN_CPU);
-			r = ttm_bo_validate(&e->bo->tbo, &e->bo->placement,
-					    &ctx);
-			if (r)
+			usermm = amdgpu_ttm_tt_get_usermm(e->bo->tbo.ttm);
+			if (usermm && usermm != current->mm) {
+				r = -EPERM;
 				goto out_free_user_pages;
+			}
+
+			if (amdgpu_ttm_tt_is_userptr(e->bo->tbo.ttm) &&
+			    e->user_invalidated && e->user_pages) {
+				amdgpu_bo_placement_from_domain(e->bo,
+								AMDGPU_GEM_DOMAIN_CPU);
+				r = ttm_bo_validate(&e->bo->tbo, &e->bo->placement,
+						    &ctx);
+				drm_exec_retry_on_contention(&p->exec);
+				if (r)
+					goto out_free_user_pages;
+
+				amdgpu_ttm_tt_set_user_pages(e->bo->tbo.ttm,
+							     e->user_pages);
+			}
 
-			amdgpu_ttm_tt_set_user_pages(e->bo->tbo.ttm,
-						     e->user_pages);
+			kvfree(e->user_pages);
+			e->user_pages = NULL;
 		}
 
-		kvfree(e->user_pages);
-		e->user_pages = NULL;
-	}
+		amdgpu_cs_get_threshold_for_moves(p->adev, &p->bytes_moved_threshold,
+						  &p->bytes_moved_vis_threshold);
+		p->bytes_moved = 0;
+		p->bytes_moved_vis = 0;
 
-	amdgpu_cs_get_threshold_for_moves(p->adev, &p->bytes_moved_threshold,
-					  &p->bytes_moved_vis_threshold);
-	p->bytes_moved = 0;
-	p->bytes_moved_vis = 0;
+		r = amdgpu_vm_validate(p->adev, &fpriv->vm, NULL,
+				       amdgpu_cs_bo_validate, p);
+		drm_exec_retry_on_contention(&p->exec);
+		if (r) {
+			DRM_ERROR("amdgpu_vm_validate() failed.\n");
+			goto out_free_user_pages;
+		}
 
-	r = amdgpu_vm_validate(p->adev, &fpriv->vm, NULL,
-			       amdgpu_cs_bo_validate, p);
-	if (r) {
-		DRM_ERROR("amdgpu_vm_validate() failed.\n");
-		goto out_free_user_pages;
-	}
+		drm_exec_for_each_locked_object(&p->exec, index, obj) {
+			r = amdgpu_cs_bo_validate(p, gem_to_amdgpu_bo(obj));
+			drm_exec_retry_on_contention(&p->exec);
+			if (unlikely(r))
+				goto out_free_user_pages;
+		}
 
-	drm_exec_for_each_locked_object(&p->exec, index, obj) {
-		r = amdgpu_cs_bo_validate(p, gem_to_amdgpu_bo(obj));
-		if (unlikely(r))
-			goto out_free_user_pages;
+		amdgpu_cs_report_moved_bytes(p->adev, p->bytes_moved,
+					     p->bytes_moved_vis);
 	}
 
 	if (p->uf_bo) {
@@ -973,9 +982,6 @@ static int amdgpu_cs_parser_bos(struct amdgpu_cs_parser *p,
 		p->gang_leader->uf_addr += amdgpu_bo_gpu_offset(p->uf_bo);
 	}
 
-	amdgpu_cs_report_moved_bytes(p->adev, p->bytes_moved,
-				     p->bytes_moved_vis);
-
 	for (i = 0; i < p->gang_size; ++i)
 		amdgpu_job_set_resources(p->jobs[i], p->bo_list->gds_obj,
 					 p->bo_list->gws_obj,
-- 
2.34.1