drm/i915: Split vma exec_link/evict_link

Currently the vma has one link member that is used for both holding its
place in the execbuf reservation list, and in any eviction list. This
dual property is quite tricky and error prone.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170615081435.17699-3-chris@chris-wilson.co.uk

drivers/gpu/drm/i915/i915_gem_evict.c

@@ -62,7 +62,7 @@ mark_free(struct drm_mm_scan *scan,
 	if (flags & PIN_NONFAULT && !list_empty(&vma->obj->userfault_link))
 		return false;
 
-	list_add(&vma->exec_list, unwind);
+	list_add(&vma->evict_link, unwind);
 	return drm_mm_scan_add_block(scan, &vma->node);
 }
 
@@ -154,7 +154,7 @@ search_again:
 	} while (*++phase);
 
 	/* Nothing found, clean up and bail out! */
-	list_for_each_entry_safe(vma, next, &eviction_list, exec_list) {
+	list_for_each_entry_safe(vma, next, &eviction_list, evict_link) {
 		ret = drm_mm_scan_remove_block(&scan, &vma->node);
 		BUG_ON(ret);
 	}
@@ -200,16 +200,16 @@ found:
 	 * calling unbind (which may remove the active reference
 	 * of any of our objects, thus corrupting the list).
 	 */
-	list_for_each_entry_safe(vma, next, &eviction_list, exec_list) {
+	list_for_each_entry_safe(vma, next, &eviction_list, evict_link) {
 		if (drm_mm_scan_remove_block(&scan, &vma->node))
 			__i915_vma_pin(vma);
 		else
-			list_del(&vma->exec_list);
+			list_del(&vma->evict_link);
 	}
 
 	/* Unbinding will emit any required flushes */
 	ret = 0;
-	list_for_each_entry_safe(vma, next, &eviction_list, exec_list) {
+	list_for_each_entry_safe(vma, next, &eviction_list, evict_link) {
 		__i915_vma_unpin(vma);
 		if (ret == 0)
 			ret = i915_vma_unbind(vma);
@@ -322,10 +322,10 @@ int i915_gem_evict_for_node(struct i915_address_space *vm,
 		 * reference) another in our eviction list.
 		 */
 		__i915_vma_pin(vma);
-		list_add(&vma->exec_list, &eviction_list);
+		list_add(&vma->evict_link, &eviction_list);
 	}
 
-	list_for_each_entry_safe(vma, next, &eviction_list, exec_list) {
+	list_for_each_entry_safe(vma, next, &eviction_list, evict_link) {
 		__i915_vma_unpin(vma);
 		if (ret == 0)
 			ret = i915_vma_unbind(vma);

drivers/gpu/drm/i915/i915_gem_execbuffer.c

@@ -136,7 +136,7 @@ eb_reset(struct i915_execbuffer *eb)
 {
 	struct i915_vma *vma;
 
-	list_for_each_entry(vma, &eb->vmas, exec_list) {
+	list_for_each_entry(vma, &eb->vmas, exec_link) {
 		eb_unreserve_vma(vma);
 		i915_vma_put(vma);
 		vma->exec_entry = NULL;
@@ -149,7 +149,7 @@ eb_reset(struct i915_execbuffer *eb)
 static struct i915_vma *
 eb_get_batch(struct i915_execbuffer *eb)
 {
-	struct i915_vma *vma = list_entry(eb->vmas.prev, typeof(*vma), exec_list);
+	struct i915_vma *vma = list_entry(eb->vmas.prev, typeof(*vma), exec_link);
 
 	/*
 	 * SNA is doing fancy tricks with compressing batch buffers, which leads
@@ -226,7 +226,7 @@ eb_lookup_vmas(struct i915_execbuffer *eb)
 		}
 
 		/* Transfer ownership from the objects list to the vmas list. */
-		list_add_tail(&vma->exec_list, &eb->vmas);
+		list_add_tail(&vma->exec_link, &eb->vmas);
 		list_del_init(&obj->obj_exec_link);
 
 		vma->exec_entry = &eb->exec[i];
@@ -285,7 +285,7 @@ static void eb_destroy(struct i915_execbuffer *eb)
 {
 	struct i915_vma *vma;
 
-	list_for_each_entry(vma, &eb->vmas, exec_list) {
+	list_for_each_entry(vma, &eb->vmas, exec_link) {
 		if (!vma->exec_entry)
 			continue;
 
@@ -751,7 +751,7 @@ static int eb_relocate(struct i915_execbuffer *eb)
 	struct i915_vma *vma;
 	int ret = 0;
 
-	list_for_each_entry(vma, &eb->vmas, exec_list) {
+	list_for_each_entry(vma, &eb->vmas, exec_link) {
 		ret = eb_relocate_vma(vma, eb);
 		if (ret)
 			break;
@@ -904,7 +904,7 @@ static int eb_reserve(struct i915_execbuffer *eb)
 		struct drm_i915_gem_exec_object2 *entry;
 		bool need_fence, need_mappable;
 
-		vma = list_first_entry(&eb->vmas, struct i915_vma, exec_list);
+		vma = list_first_entry(&eb->vmas, struct i915_vma, exec_link);
 		obj = vma->obj;
 		entry = vma->exec_entry;
 
@@ -920,12 +920,12 @@ static int eb_reserve(struct i915_execbuffer *eb)
 		need_mappable = need_fence || need_reloc_mappable(vma);
 
 		if (entry->flags & EXEC_OBJECT_PINNED)
-			list_move_tail(&vma->exec_list, &pinned_vmas);
+			list_move_tail(&vma->exec_link, &pinned_vmas);
 		else if (need_mappable) {
 			entry->flags |= __EXEC_OBJECT_NEEDS_MAP;
-			list_move(&vma->exec_list, &ordered_vmas);
+			list_move(&vma->exec_link, &ordered_vmas);
 		} else
-			list_move_tail(&vma->exec_list, &ordered_vmas);
+			list_move_tail(&vma->exec_link, &ordered_vmas);
 
 		obj->base.pending_read_domains = I915_GEM_GPU_DOMAINS & ~I915_GEM_DOMAIN_COMMAND;
 		obj->base.pending_write_domain = 0;
@@ -950,7 +950,7 @@ static int eb_reserve(struct i915_execbuffer *eb)
 		int ret = 0;
 
 		/* Unbind any ill-fitting objects or pin. */
-		list_for_each_entry(vma, &eb->vmas, exec_list) {
+		list_for_each_entry(vma, &eb->vmas, exec_link) {
 			if (!drm_mm_node_allocated(&vma->node))
 				continue;
 
@@ -963,7 +963,7 @@ static int eb_reserve(struct i915_execbuffer *eb)
 		}
 
 		/* Bind fresh objects */
-		list_for_each_entry(vma, &eb->vmas, exec_list) {
+		list_for_each_entry(vma, &eb->vmas, exec_link) {
 			if (drm_mm_node_allocated(&vma->node))
 				continue;
 
@@ -977,7 +977,7 @@ err:
 			return ret;
 
 		/* Decrement pin count for bound objects */
-		list_for_each_entry(vma, &eb->vmas, exec_list)
+		list_for_each_entry(vma, &eb->vmas, exec_link)
 			eb_unreserve_vma(vma);
 
 		ret = i915_gem_evict_vm(eb->vm, true);
@@ -1066,7 +1066,7 @@ eb_relocate_slow(struct i915_execbuffer *eb)
 	if (ret)
 		goto err;
 
-	list_for_each_entry(vma, &eb->vmas, exec_list) {
+	list_for_each_entry(vma, &eb->vmas, exec_link) {
 		int idx = vma->exec_entry - eb->exec;
 
 		ret = eb_relocate_vma_slow(vma, eb, reloc + reloc_offset[idx]);
@@ -1092,7 +1092,7 @@ eb_move_to_gpu(struct i915_execbuffer *eb)
 	struct i915_vma *vma;
 	int ret;
 
-	list_for_each_entry(vma, &eb->vmas, exec_list) {
+	list_for_each_entry(vma, &eb->vmas, exec_link) {
 		struct drm_i915_gem_object *obj = vma->obj;
 
 		if (vma->exec_entry->flags & EXEC_OBJECT_CAPTURE) {
@@ -1314,7 +1314,7 @@ eb_move_to_active(struct i915_execbuffer *eb)
 {
 	struct i915_vma *vma;
 
-	list_for_each_entry(vma, &eb->vmas, exec_list) {
+	list_for_each_entry(vma, &eb->vmas, exec_link) {
 		struct drm_i915_gem_object *obj = vma->obj;
 
 		obj->base.write_domain = obj->base.pending_write_domain;
@@ -1388,7 +1388,7 @@ static struct i915_vma *eb_parse(struct i915_execbuffer *eb, bool is_master)
 		memset(&eb->shadow_exec_entry, 0, sizeof(*vma->exec_entry));
 	vma->exec_entry->flags = __EXEC_OBJECT_HAS_PIN;
 	i915_gem_object_get(shadow_batch_obj);
-	list_add_tail(&vma->exec_list, &eb->vmas);
+	list_add_tail(&vma->exec_link, &eb->vmas);
 
 out:
 	i915_gem_object_unpin_pages(shadow_batch_obj);

drivers/gpu/drm/i915/i915_vma.h

@@ -100,8 +100,11 @@ struct i915_vma {
 	struct list_head obj_link; /* Link in the object's VMA list */
 	struct rb_node obj_node;
 
-	/** This vma's place in the batchbuffer or on the eviction list */
-	struct list_head exec_list;
+	/** This vma's place in the execbuf reservation list */
+	struct list_head exec_link;
+
+	/** This vma's place in the eviction list */
+	struct list_head evict_link;
 
 	/**
 	 * Used for performing relocations during execbuffer insertion.