11 files changed, 102 insertions, 33 deletions

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.c b/drivers/gpu/drm/i915/gem/i915_gem_object.c
index d5197a2a106f..4ea97fca9c35 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_object.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_object.c
@@ -63,6 +63,8 @@ void i915_gem_object_init(struct drm_i915_gem_object *obj,
 	spin_lock_init(&obj->vma.lock);
 	INIT_LIST_HEAD(&obj->vma.list);
 
+	INIT_LIST_HEAD(&obj->mm.link);
+
 	INIT_LIST_HEAD(&obj->lut_list);
 	INIT_LIST_HEAD(&obj->batch_pool_link);
 
@@ -273,14 +275,7 @@ void i915_gem_free_object(struct drm_gem_object *gem_obj)
 	 * or else we may oom whilst there are plenty of deferred
 	 * freed objects.
 	 */
-	if (i915_gem_object_has_pages(obj) &&
-	    i915_gem_object_is_shrinkable(obj)) {
-		unsigned long flags;
-
-		spin_lock_irqsave(&i915->mm.obj_lock, flags);
-		list_del_init(&obj->mm.link);
-		spin_unlock_irqrestore(&i915->mm.obj_lock, flags);
-	}
+	i915_gem_object_make_unshrinkable(obj);
 
 	/*
 	 * Since we require blocking on struct_mutex to unbind the freed
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.h b/drivers/gpu/drm/i915/gem/i915_gem_object.h
index 67aea07ea019..3714cf234d64 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_object.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_object.h
@@ -394,6 +394,10 @@ i915_gem_object_pin_to_display_plane(struct drm_i915_gem_object *obj,
 				     unsigned int flags);
 void i915_gem_object_unpin_from_display_plane(struct i915_vma *vma);
 
+void i915_gem_object_make_unshrinkable(struct drm_i915_gem_object *obj);
+void i915_gem_object_make_shrinkable(struct drm_i915_gem_object *obj);
+void i915_gem_object_make_purgeable(struct drm_i915_gem_object *obj);
+
 static inline bool cpu_write_needs_clflush(struct drm_i915_gem_object *obj)
 {
 	if (obj->cache_dirty)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_pages.c b/drivers/gpu/drm/i915/gem/i915_gem_pages.c
index b36ad269f4ea..92ad3cc220e3 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_pages.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_pages.c
@@ -153,24 +153,13 @@ static void __i915_gem_object_reset_page_iter(struct drm_i915_gem_object *obj)
 struct sg_table *
 __i915_gem_object_unset_pages(struct drm_i915_gem_object *obj)
 {
-	struct drm_i915_private *i915 = to_i915(obj->base.dev);
 	struct sg_table *pages;
 
 	pages = fetch_and_zero(&obj->mm.pages);
 	if (IS_ERR_OR_NULL(pages))
 		return pages;
 
-	if (i915_gem_object_is_shrinkable(obj)) {
-		unsigned long flags;
-
-		spin_lock_irqsave(&i915->mm.obj_lock, flags);
-
-		list_del(&obj->mm.link);
-		i915->mm.shrink_count--;
-		i915->mm.shrink_memory -= obj->base.size;
-
-		spin_unlock_irqrestore(&i915->mm.obj_lock, flags);
-	}
+	i915_gem_object_make_unshrinkable(obj);
 
 	if (obj->mm.mapping) {
 		void *ptr;
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_shrinker.c b/drivers/gpu/drm/i915/gem/i915_gem_shrinker.c
index 3f4c6bdcc3c3..5ab7df53c2a0 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_shrinker.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_shrinker.c
@@ -530,3 +530,61 @@ void i915_gem_shrinker_taints_mutex(struct drm_i915_private *i915,
 	if (unlock)
 		mutex_release(&i915->drm.struct_mutex.dep_map, 0, _RET_IP_);
 }
+
+#define obj_to_i915(obj__) to_i915((obj__)->base.dev)
+
+void i915_gem_object_make_unshrinkable(struct drm_i915_gem_object *obj)
+{
+	/*
+	 * We can only be called while the pages are pinned or when
+	 * the pages are released. If pinned, we should only be called
+	 * from a single caller under controlled conditions; and on release
+	 * only one caller may release us. Neither the two may cross.
+	 */
+	if (!list_empty(&obj->mm.link)) { /* pinned by caller */
+		struct drm_i915_private *i915 = obj_to_i915(obj);
+		unsigned long flags;
+
+		spin_lock_irqsave(&i915->mm.obj_lock, flags);
+		GEM_BUG_ON(list_empty(&obj->mm.link));
+
+		list_del_init(&obj->mm.link);
+		i915->mm.shrink_count--;
+		i915->mm.shrink_memory -= obj->base.size;
+
+		spin_unlock_irqrestore(&i915->mm.obj_lock, flags);
+	}
+}
+
+static void __i915_gem_object_make_shrinkable(struct drm_i915_gem_object *obj,
+					      struct list_head *head)
+{
+	GEM_BUG_ON(!i915_gem_object_has_pages(obj));
+	GEM_BUG_ON(!list_empty(&obj->mm.link));
+
+	if (i915_gem_object_is_shrinkable(obj)) {
+		struct drm_i915_private *i915 = obj_to_i915(obj);
+		unsigned long flags;
+
+		spin_lock_irqsave(&i915->mm.obj_lock, flags);
+		GEM_BUG_ON(!kref_read(&obj->base.refcount));
+
+		list_add_tail(&obj->mm.link, head);
+		i915->mm.shrink_count++;
+		i915->mm.shrink_memory += obj->base.size;
+
+		spin_unlock_irqrestore(&i915->mm.obj_lock, flags);
+	}
+}
+
+void i915_gem_object_make_shrinkable(struct drm_i915_gem_object *obj)
+{
+	__i915_gem_object_make_shrinkable(obj,
+					  &obj_to_i915(obj)->mm.shrink_list);
+}
+
+void i915_gem_object_make_purgeable(struct drm_i915_gem_object *obj)
+{
+	__i915_gem_object_make_shrinkable(obj,
+					  &obj_to_i915(obj)->mm.purge_list);
+}
diff --git a/drivers/gpu/drm/i915/gt/intel_context.c b/drivers/gpu/drm/i915/gt/intel_context.c
index 34c8e37a73b8..c8777e222b12 100644
--- a/drivers/gpu/drm/i915/gt/intel_context.c
+++ b/drivers/gpu/drm/i915/gt/intel_context.c
@@ -118,7 +118,7 @@ static int __context_pin_state(struct i915_vma *vma)
 	 * And mark it as a globally pinned object to let the shrinker know
 	 * it cannot reclaim the object until we release it.
 	 */
-	vma->obj->pin_global++;
+	i915_vma_make_unshrinkable(vma);
 	vma->obj->mm.dirty = true;
 
 	return 0;
@@ -126,8 +126,8 @@ static int __context_pin_state(struct i915_vma *vma)
 
 static void __context_unpin_state(struct i915_vma *vma)
 {
-	vma->obj->pin_global--;
 	__i915_vma_unpin(vma);
+	i915_vma_make_shrinkable(vma);
 }
 
 static void __intel_context_retire(struct i915_active *active)
diff --git a/drivers/gpu/drm/i915/gt/intel_gt.c b/drivers/gpu/drm/i915/gt/intel_gt.c
index 5a7d1a34e429..75d8c5ee6ecb 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt.c
+++ b/drivers/gpu/drm/i915/gt/intel_gt.c
@@ -248,7 +248,8 @@ int intel_gt_init_scratch(struct intel_gt *gt, unsigned int size)
 	if (ret)
 		goto err_unref;
 
-	gt->scratch = vma;
+	gt->scratch = i915_vma_make_unshrinkable(vma);
+
 	return 0;
 
 err_unref:
diff --git a/drivers/gpu/drm/i915/gt/intel_ringbuffer.c b/drivers/gpu/drm/i915/gt/intel_ringbuffer.c
index 8d24a49e5139..aa2f06b80961 100644
--- a/drivers/gpu/drm/i915/gt/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/gt/intel_ringbuffer.c
@@ -1222,7 +1222,7 @@ int intel_ring_pin(struct intel_ring *ring)
 		goto err_ring;
 	}
 
-	vma->obj->pin_global++;
+	i915_vma_make_unshrinkable(vma);
 
 	GEM_BUG_ON(ring->vaddr);
 	ring->vaddr = addr;
@@ -1251,6 +1251,8 @@ void intel_ring_reset(struct intel_ring *ring, u32 tail)
 
 void intel_ring_unpin(struct intel_ring *ring)
 {
+	struct i915_vma *vma = ring->vma;
+
 	if (!atomic_dec_and_test(&ring->pin_count))
 		return;
 
@@ -1259,18 +1261,17 @@ void intel_ring_unpin(struct intel_ring *ring)
 	/* Discard any unused bytes beyond that submitted to hw. */
 	intel_ring_reset(ring, ring->tail);
 
-	GEM_BUG_ON(!ring->vma);
-	i915_vma_unset_ggtt_write(ring->vma);
-	if (i915_vma_is_map_and_fenceable(ring->vma))
-		i915_vma_unpin_iomap(ring->vma);
+	i915_vma_unset_ggtt_write(vma);
+	if (i915_vma_is_map_and_fenceable(vma))
+		i915_vma_unpin_iomap(vma);
 	else
-		i915_gem_object_unpin_map(ring->vma->obj);
+		i915_gem_object_unpin_map(vma->obj);
 
 	GEM_BUG_ON(!ring->vaddr);
 	ring->vaddr = NULL;
 
-	ring->vma->obj->pin_global--;
-	i915_vma_unpin(ring->vma);
+	i915_vma_unpin(vma);
+	i915_vma_make_purgeable(vma);
 
 	intel_timeline_unpin(ring->timeline);
 }
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc.c b/drivers/gpu/drm/i915/gt/uc/intel_guc.c
index da14f8067497..0ee8139885a5 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc.c
@@ -626,7 +626,7 @@ struct i915_vma *intel_guc_allocate_vma(struct intel_guc *guc, u32 size)
 		goto err;
 	}
 
-	return vma;
+	return i915_vma_make_unshrinkable(vma);
 
 err:
 	i915_gem_object_put(obj);
diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 461a8dd4cc47..19f156a7f501 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -363,8 +363,9 @@ static int i915_gem_object_info(struct seq_file *m, void *data)
 	struct drm_i915_private *i915 = node_to_i915(m->private);
 	int ret;
 
-	seq_printf(m, "%u shrinkable objects, %llu bytes\n",
+	seq_printf(m, "%u shrinkable [%u free] objects, %llu bytes\n",
 		   i915->mm.shrink_count,
+		   atomic_read(&i915->mm.free_count),
 		   i915->mm.shrink_memory);
 
 	seq_putc(m, '\n');
diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c
index 7734d6218ce7..101a2bb416a6 100644
--- a/drivers/gpu/drm/i915/i915_vma.c
+++ b/drivers/gpu/drm/i915/i915_vma.c
@@ -1017,6 +1017,22 @@ unpin:
 	return 0;
 }
 
+struct i915_vma *i915_vma_make_unshrinkable(struct i915_vma *vma)
+{
+	i915_gem_object_make_unshrinkable(vma->obj);
+	return vma;
+}
+
+void i915_vma_make_shrinkable(struct i915_vma *vma)
+{
+	i915_gem_object_make_shrinkable(vma->obj);
+}
+
+void i915_vma_make_purgeable(struct i915_vma *vma)
+{
+	i915_gem_object_make_purgeable(vma->obj);
+}
+
 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
 #include "selftests/i915_vma.c"
 #endif
diff --git a/drivers/gpu/drm/i915/i915_vma.h b/drivers/gpu/drm/i915/i915_vma.h
index 4b769db649bf..5c4224749bde 100644
--- a/drivers/gpu/drm/i915/i915_vma.h
+++ b/drivers/gpu/drm/i915/i915_vma.h
@@ -459,4 +459,8 @@ void i915_vma_parked(struct drm_i915_private *i915);
 struct i915_vma *i915_vma_alloc(void);
 void i915_vma_free(struct i915_vma *vma);
 
+struct i915_vma *i915_vma_make_unshrinkable(struct i915_vma *vma);
+void i915_vma_make_shrinkable(struct i915_vma *vma);
+void i915_vma_make_purgeable(struct i915_vma *vma);
+
 #endif