drm/msm/gem: Remove active refcnt

At this point the pinned refcnt is sufficient, and the shrinker is
already prepared to encounter objects which are still active according
to fences attached to the resv.
Signed-off-by: Rob Clark <robdclark@chromium.org>
Patchwork: https://patchwork.freedesktop.org/patch/496122/
Link: https://lore.kernel.org/r/20220802155152.1727594-9-robdclark@gmail.com

drivers/gpu/drm/msm/msm_gem.c

@@ -734,8 +734,7 @@ int msm_gem_madvise(struct drm_gem_object *obj, unsigned madv)
 	/* If the obj is inactive, we might need to move it
 	 * between inactive lists
 	 */
-	if (msm_obj->active_count == 0)
-		update_lru(obj);
+	update_lru(obj);
 
 	msm_gem_unlock(obj);
 
@@ -788,7 +787,6 @@ void msm_gem_evict(struct drm_gem_object *obj)
 	GEM_WARN_ON(!msm_gem_is_locked(obj));
 	GEM_WARN_ON(is_unevictable(msm_obj));
 	GEM_WARN_ON(!msm_obj->evictable);
-	GEM_WARN_ON(msm_obj->active_count);
 
 	/* Get rid of any iommu mapping(s): */
 	put_iova_spaces(obj, false);
@@ -813,37 +811,6 @@ void msm_gem_vunmap(struct drm_gem_object *obj)
 	msm_obj->vaddr = NULL;
 }
 
-void msm_gem_active_get(struct drm_gem_object *obj, struct msm_gpu *gpu)
-{
-	struct msm_gem_object *msm_obj = to_msm_bo(obj);
-	struct msm_drm_private *priv = obj->dev->dev_private;
-
-	might_sleep();
-	GEM_WARN_ON(!msm_gem_is_locked(obj));
-	GEM_WARN_ON(msm_obj->madv != MSM_MADV_WILLNEED);
-	GEM_WARN_ON(msm_obj->dontneed);
-
-	if (msm_obj->active_count++ == 0) {
-		mutex_lock(&priv->mm_lock);
-		if (msm_obj->evictable)
-			mark_unevictable(msm_obj);
-		list_move_tail(&msm_obj->mm_list, &gpu->active_list);
-		mutex_unlock(&priv->mm_lock);
-	}
-}
-
-void msm_gem_active_put(struct drm_gem_object *obj)
-{
-	struct msm_gem_object *msm_obj = to_msm_bo(obj);
-
-	might_sleep();
-	GEM_WARN_ON(!msm_gem_is_locked(obj));
-
-	if (--msm_obj->active_count == 0) {
-		update_lru(obj);
-	}
-}
-
 static void update_lru(struct drm_gem_object *obj)
 {
 	struct msm_drm_private *priv = obj->dev->dev_private;
@@ -851,9 +818,6 @@ static void update_lru(struct drm_gem_object *obj)
 
 	GEM_WARN_ON(!msm_gem_is_locked(&msm_obj->base));
 
-	if (msm_obj->active_count != 0)
-		return;
-
 	mutex_lock(&priv->mm_lock);
 
 	if (msm_obj->dontneed)
@@ -926,7 +890,7 @@ void msm_gem_describe(struct drm_gem_object *obj, struct seq_file *m,
 	stats->all.count++;
 	stats->all.size += obj->size;
 
-	if (is_active(msm_obj)) {
+	if (msm_gem_active(obj)) {
 		stats->active.count++;
 		stats->active.size += obj->size;
 	}
@@ -954,7 +918,7 @@ void msm_gem_describe(struct drm_gem_object *obj, struct seq_file *m,
 	}
 
 	seq_printf(m, "%08x: %c %2d (%2d) %08llx %p",
-			msm_obj->flags, is_active(msm_obj) ? 'A' : 'I',
+			msm_obj->flags, msm_gem_active(obj) ? 'A' : 'I',
 			obj->name, kref_read(&obj->refcount),
 			off, msm_obj->vaddr);
 
@@ -1037,9 +1001,6 @@ static void msm_gem_free_object(struct drm_gem_object *obj)
 	list_del(&msm_obj->mm_list);
 	mutex_unlock(&priv->mm_lock);
 
-	/* object should not be on active list: */
-	GEM_WARN_ON(is_active(msm_obj));
-
 	put_iova_spaces(obj, true);
 
 	if (obj->import_attach) {

drivers/gpu/drm/msm/msm_gem.h

@@ -138,7 +138,6 @@ struct msm_gem_object {
 
 	char name[32]; /* Identifier to print for the debugfs files */
 
-	int active_count;
 	int pin_count;
 };
 #define to_msm_bo(x) container_of(x, struct msm_gem_object, base)
@@ -171,8 +170,6 @@ void *msm_gem_get_vaddr_active(struct drm_gem_object *obj);
 void msm_gem_put_vaddr_locked(struct drm_gem_object *obj);
 void msm_gem_put_vaddr(struct drm_gem_object *obj);
 int msm_gem_madvise(struct drm_gem_object *obj, unsigned madv);
-void msm_gem_active_get(struct drm_gem_object *obj, struct msm_gpu *gpu);
-void msm_gem_active_put(struct drm_gem_object *obj);
 bool msm_gem_active(struct drm_gem_object *obj);
 int msm_gem_cpu_prep(struct drm_gem_object *obj, uint32_t op, ktime_t *timeout);
 int msm_gem_cpu_fini(struct drm_gem_object *obj);
@@ -245,12 +242,6 @@ msm_gem_is_locked(struct drm_gem_object *obj)
 	return dma_resv_is_locked(obj->resv) || (kref_read(&obj->refcount) == 0);
 }
 
-static inline bool is_active(struct msm_gem_object *msm_obj)
-{
-	GEM_WARN_ON(!msm_gem_is_locked(&msm_obj->base));
-	return msm_obj->active_count;
-}
-
 /* imported/exported objects are not purgeable: */
 static inline bool is_unpurgeable(struct msm_gem_object *msm_obj)
 {
@@ -391,9 +382,8 @@ struct msm_gem_submit {
 /* make sure these don't conflict w/ MSM_SUBMIT_BO_x */
 #define BO_VALID	0x8000	/* is current addr in cmdstream correct/valid? */
 #define BO_LOCKED	0x4000	/* obj lock is held */
-#define BO_ACTIVE	0x2000	/* active refcnt is held */
-#define BO_OBJ_PINNED	0x1000	/* obj (pages) is pinned and on active list */
-#define BO_VMA_PINNED	0x0800	/* vma (virtual address) is pinned */
+#define BO_OBJ_PINNED	0x2000	/* obj (pages) is pinned and on active list */
+#define BO_VMA_PINNED	0x1000	/* vma (virtual address) is pinned */
 		uint32_t flags;
 		union {
 			struct msm_gem_object *obj;

drivers/gpu/drm/msm/msm_gem_submit.c

@@ -243,17 +243,13 @@ static void submit_cleanup_bo(struct msm_gem_submit *submit, int i,
 	if (flags & BO_OBJ_PINNED)
 		msm_gem_unpin_locked(obj);
 
-	if (flags & BO_ACTIVE)
-		msm_gem_active_put(obj);
-
 	if (flags & BO_LOCKED)
 		dma_resv_unlock(obj->resv);
 }
 
 static void submit_unlock_unpin_bo(struct msm_gem_submit *submit, int i)
 {
-	unsigned cleanup_flags = BO_VMA_PINNED | BO_OBJ_PINNED |
-				 BO_ACTIVE | BO_LOCKED;
+	unsigned cleanup_flags = BO_VMA_PINNED | BO_OBJ_PINNED | BO_LOCKED;
 	submit_cleanup_bo(submit, i, cleanup_flags);
 
 	if (!(submit->bos[i].flags & BO_VALID))
@@ -358,18 +354,6 @@ static int submit_pin_objects(struct msm_gem_submit *submit)
 
 	submit->valid = true;
 
-	/*
-	 * Increment active_count first, so if under memory pressure, we
-	 * don't inadvertently evict a bo needed by the submit in order
-	 * to pin an earlier bo in the same submit.
-	 */
-	for (i = 0; i < submit->nr_bos; i++) {
-		struct drm_gem_object *obj = &submit->bos[i].obj->base;
-
-		msm_gem_active_get(obj, submit->gpu);
-		submit->bos[i].flags |= BO_ACTIVE;
-	}
-
 	for (i = 0; i < submit->nr_bos; i++) {
 		struct drm_gem_object *obj = &submit->bos[i].obj->base;
 		struct msm_gem_vma *vma;
@@ -521,7 +505,7 @@ static void submit_cleanup(struct msm_gem_submit *submit, bool error)
 	unsigned i;
 
 	if (error)
-		cleanup_flags |= BO_VMA_PINNED | BO_OBJ_PINNED | BO_ACTIVE;
+		cleanup_flags |= BO_VMA_PINNED | BO_OBJ_PINNED;
 
 	for (i = 0; i < submit->nr_bos; i++) {
 		struct msm_gem_object *msm_obj = submit->bos[i].obj;
@@ -540,7 +524,7 @@ void msm_submit_retire(struct msm_gem_submit *submit)
 
 		msm_gem_lock(obj);
 		/* Note, VMA already fence-unpinned before submit: */
-		submit_cleanup_bo(submit, i, BO_OBJ_PINNED | BO_ACTIVE);
+		submit_cleanup_bo(submit, i, BO_OBJ_PINNED);
 		msm_gem_unlock(obj);
 		drm_gem_object_put(obj);
 	}