[39/45] drm/i915: Move object close under its own lock

Submitted by Chris Wilson on April 25, 2019, 9:19 a.m.

Details

Message ID 20190425092004.9995-39-chris@chris-wilson.co.uk
State New
Headers show
Series "Series without cover letter" ( rev: 2 1 ) in Intel GFX

Browsing this patch as part of:
"Series without cover letter" rev 2 in Intel GFX
<< prev patch [38/45] next patch >>

Commit Message

Chris Wilson April 25, 2019, 9:19 a.m.
Use i915_gem_object_lock() to guard the LUT and active reference to
allow us to break free of struct_mutex for handling GEM_CLOSE.

Testcase: igt/gem_close_race
Testcase: igt/gem_exec_parallel
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/gem/i915_gem_context.c   | 76 ++++++++++---------
 .../gpu/drm/i915/gem/i915_gem_context_types.h | 12 +--
 .../gpu/drm/i915/gem/i915_gem_execbuffer.c    | 23 ++++--
 drivers/gpu/drm/i915/gem/i915_gem_object.c    | 38 ++++++----
 .../gpu/drm/i915/gem/i915_gem_object_types.h  |  1 -
 .../gpu/drm/i915/gem/selftests/mock_context.c |  1 -
 drivers/gpu/drm/i915/i915_drv.h               |  4 +-
 drivers/gpu/drm/i915/i915_gem.c               |  1 +
 drivers/gpu/drm/i915/i915_gem_gtt.c           |  1 +
 drivers/gpu/drm/i915/i915_timeline.c          | 13 ++--
 drivers/gpu/drm/i915/i915_vma.c               | 42 ++++++----
 drivers/gpu/drm/i915/i915_vma.h               | 17 ++---
 .../gpu/drm/i915/selftests/mock_gem_device.c  |  1 +
 13 files changed, 132 insertions(+), 98 deletions(-)

Patch hide | download patch | download mbox

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context.c b/drivers/gpu/drm/i915/gem/i915_gem_context.c
index b61c63618b87..d4f13278d5b6 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_context.c
@@ -95,24 +95,42 @@  void i915_lut_handle_free(struct i915_lut_handle *lut)
 
 static void lut_close(struct i915_gem_context *ctx)
 {
-	struct i915_lut_handle *lut, *ln;
 	struct radix_tree_iter iter;
 	void __rcu **slot;
 
-	list_for_each_entry_safe(lut, ln, &ctx->handles_list, ctx_link) {
-		list_del(&lut->obj_link);
-		i915_lut_handle_free(lut);
-	}
-	INIT_LIST_HEAD(&ctx->handles_list);
+	lockdep_assert_held(&ctx->mutex);
 
 	rcu_read_lock();
 	radix_tree_for_each_slot(slot, &ctx->handles_vma, &iter, 0) {
 		struct i915_vma *vma = rcu_dereference_raw(*slot);
-
-		radix_tree_iter_delete(&ctx->handles_vma, &iter, slot);
-
-		vma->open_count--;
-		i915_vma_put(vma);
+		struct drm_i915_gem_object *obj = vma->obj;
+		struct i915_lut_handle *lut;
+		bool found = false;
+
+		rcu_read_unlock();
+		i915_gem_object_lock(obj);
+		list_for_each_entry(lut, &obj->lut_list, obj_link) {
+			if (lut->ctx != ctx)
+				continue;
+
+			if (lut->handle != iter.index)
+				continue;
+
+			list_del(&lut->obj_link);
+			i915_lut_handle_free(lut);
+			found = true;
+			break;
+		}
+		i915_gem_object_unlock(obj);
+		rcu_read_lock();
+
+		if (found) {
+			radix_tree_iter_delete(&ctx->handles_vma, &iter, slot);
+			if (atomic_dec_and_test(&vma->open_count) &&
+			    !i915_vma_is_ggtt(vma))
+				i915_vma_close(vma);
+			i915_gem_object_put(obj);
+		}
 	}
 	rcu_read_unlock();
 }
@@ -238,15 +256,9 @@  static void free_engines(struct i915_gem_engines *e)
 	__free_engines(e, e->num_engines);
 }
 
-static void free_engines_rcu(struct work_struct *wrk)
+static void free_engines_rcu(struct rcu_head *rcu)
 {
-	struct i915_gem_engines *e =
-		container_of(wrk, struct i915_gem_engines, rcu.work);
-	struct drm_i915_private *i915 = e->i915;
-
-	mutex_lock(&i915->drm.struct_mutex);
-	free_engines(e);
-	mutex_unlock(&i915->drm.struct_mutex);
+	free_engines(container_of(rcu, struct i915_gem_engines, rcu));
 }
 
 static struct i915_gem_engines *default_engines(struct i915_gem_context *ctx)
@@ -259,7 +271,7 @@  static struct i915_gem_engines *default_engines(struct i915_gem_context *ctx)
 	if (!e)
 		return ERR_PTR(-ENOMEM);
 
-	e->i915 = ctx->i915;
+	init_rcu_head(&e->rcu);
 	for_each_engine(engine, ctx->i915, id) {
 		struct intel_context *ce;
 
@@ -347,7 +359,10 @@  void i915_gem_context_release(struct kref *ref)
 
 static void context_close(struct i915_gem_context *ctx)
 {
+	mutex_lock(&ctx->mutex);
+
 	i915_gem_context_set_closed(ctx);
+	ctx->file_priv = ERR_PTR(-EBADF);
 
 	/*
 	 * This context will never again be assinged to HW, so we can
@@ -362,7 +377,7 @@  static void context_close(struct i915_gem_context *ctx)
 	 */
 	lut_close(ctx);
 
-	ctx->file_priv = ERR_PTR(-EBADF);
+	mutex_unlock(&ctx->mutex);
 	i915_gem_context_put(ctx);
 }
 
@@ -417,7 +432,6 @@  __create_context(struct drm_i915_private *dev_priv)
 	RCU_INIT_POINTER(ctx->engines, e);
 
 	INIT_RADIX_TREE(&ctx->handles_vma, GFP_KERNEL);
-	INIT_LIST_HEAD(&ctx->handles_list);
 	INIT_LIST_HEAD(&ctx->hw_id_link);
 
 	/* NB: Mark all slices as needing a remap so that when the context first
@@ -760,9 +774,7 @@  int i915_gem_context_open(struct drm_i915_private *i915,
 	return 0;
 
 err_ctx:
-	mutex_lock(&i915->drm.struct_mutex);
 	context_close(ctx);
-	mutex_unlock(&i915->drm.struct_mutex);
 err:
 	idr_destroy(&file_priv->vm_idr);
 	idr_destroy(&file_priv->context_idr);
@@ -775,8 +787,6 @@  void i915_gem_context_close(struct drm_file *file)
 {
 	struct drm_i915_file_private *file_priv = file->driver_priv;
 
-	lockdep_assert_held(&file_priv->dev_priv->drm.struct_mutex);
-
 	idr_for_each(&file_priv->context_idr, context_idr_cleanup, NULL);
 	idr_destroy(&file_priv->context_idr);
 	mutex_destroy(&file_priv->context_idr_lock);
@@ -1084,7 +1094,9 @@  static int set_ppgtt(struct drm_i915_file_private *file_priv,
 		goto unlock;
 
 	/* Teardown the existing obj:vma cache, it will have to be rebuilt. */
+	mutex_lock(&ctx->mutex);
 	lut_close(ctx);
+	mutex_unlock(&ctx->mutex);
 
 	old = __set_ppgtt(ctx, ppgtt);
 
@@ -1599,7 +1611,7 @@  set_engines(struct i915_gem_context *ctx,
 	if (!set.engines)
 		return -ENOMEM;
 
-	set.engines->i915 = ctx->i915;
+	init_rcu_head(&set.engines->rcu);
 	for (n = 0; n < num_engines; n++) {
 		struct i915_engine_class_instance ci;
 		struct intel_engine_cs *engine;
@@ -1653,8 +1665,7 @@  set_engines(struct i915_gem_context *ctx,
 	rcu_swap_protected(ctx->engines, set.engines, 1);
 	mutex_unlock(&ctx->engines_mutex);
 
-	INIT_RCU_WORK(&set.engines->rcu, free_engines_rcu);
-	queue_rcu_work(system_wq, &set.engines->rcu);
+	call_rcu(&set.engines->rcu, free_engines_rcu);
 
 	return 0;
 }
@@ -1852,7 +1863,7 @@  static int clone_engines(struct i915_gem_context *dst,
 	if (!clone)
 		goto err_unlock;
 
-	clone->i915 = dst->i915;
+	init_rcu_head(&clone->rcu);
 	for (n = 0; n < e->num_engines; n++) {
 		struct intel_engine_cs *engine;
 
@@ -2124,9 +2135,7 @@  int i915_gem_context_create_ioctl(struct drm_device *dev, void *data,
 	return 0;
 
 err_ctx:
-	mutex_lock(&dev->struct_mutex);
 	context_close(ext_data.ctx);
-	mutex_unlock(&dev->struct_mutex);
 	return ret;
 }
 
@@ -2151,10 +2160,7 @@  int i915_gem_context_destroy_ioctl(struct drm_device *dev, void *data,
 	if (!ctx)
 		return -ENOENT;
 
-	mutex_lock(&dev->struct_mutex);
 	context_close(ctx);
-	mutex_unlock(&dev->struct_mutex);
-
 	return 0;
 }
 
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context_types.h b/drivers/gpu/drm/i915/gem/i915_gem_context_types.h
index fb965ded2508..3db7448b9732 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_context_types.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_context_types.h
@@ -30,8 +30,7 @@  struct i915_timeline;
 struct intel_ring;
 
 struct i915_gem_engines {
-	struct rcu_work rcu;
-	struct drm_i915_private *i915;
+	struct rcu_head rcu;
 	unsigned int num_engines;
 	struct intel_context *engines[];
 };
@@ -192,17 +191,12 @@  struct i915_gem_context {
 	/** remap_slice: Bitmask of cache lines that need remapping */
 	u8 remap_slice;
 
-	/** handles_vma: rbtree to look up our context specific obj/vma for
+	/**
+	 * handles_vma: rbtree to look up our context specific obj/vma for
 	 * the user handle. (user handles are per fd, but the binding is
 	 * per vm, which may be one per context or shared with the global GTT)
 	 */
 	struct radix_tree_root handles_vma;
-
-	/** handles_list: reverse list of all the rbtree entries in use for
-	 * this context, which allows us to free all the allocations on
-	 * context close.
-	 */
-	struct list_head handles_list;
 };
 
 #endif /* __I915_GEM_CONTEXT_TYPES_H__ */
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
index 080f69358224..5133787480ea 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
@@ -802,9 +802,6 @@  static int eb_lookup_vmas(struct i915_execbuffer *eb)
 	unsigned int i, batch;
 	int err;
 
-	if (unlikely(i915_gem_context_is_closed(eb->gem_context)))
-		return -ENOENT;
-
 	if (unlikely(i915_gem_context_is_banned(eb->gem_context)))
 		return -EIO;
 
@@ -813,6 +810,12 @@  static int eb_lookup_vmas(struct i915_execbuffer *eb)
 
 	batch = eb_batch_index(eb);
 
+	mutex_lock(&eb->gem_context->mutex);
+	if (unlikely(i915_gem_context_is_closed(eb->gem_context))) {
+		err = -ENOENT;
+		goto err_ctx;
+	}
+
 	for (i = 0; i < eb->buffer_count; i++) {
 		u32 handle = eb->exec[i].handle;
 		struct i915_lut_handle *lut;
@@ -847,12 +850,14 @@  static int eb_lookup_vmas(struct i915_execbuffer *eb)
 		}
 
 		/* transfer ref to ctx */
-		if (!vma->open_count++)
+		if (!atomic_fetch_inc(&vma->open_count))
 			i915_vma_reopen(vma);
-		list_add(&lut->obj_link, &obj->lut_list);
-		list_add(&lut->ctx_link, &eb->gem_context->handles_list);
-		lut->ctx = eb->gem_context;
 		lut->handle = handle;
+		lut->ctx = eb->gem_context;
+
+		i915_gem_object_lock(obj);
+		list_add(&lut->obj_link, &obj->lut_list);
+		i915_gem_object_unlock(obj);
 
 add_vma:
 		err = eb_add_vma(eb, i, batch, vma);
@@ -865,6 +870,8 @@  static int eb_lookup_vmas(struct i915_execbuffer *eb)
 			   eb_vma_misplaced(&eb->exec[i], vma, eb->flags[i]));
 	}
 
+	mutex_unlock(&eb->gem_context->mutex);
+
 	eb->args->flags |= __EXEC_VALIDATED;
 	return eb_reserve(eb);
 
@@ -872,6 +879,8 @@  static int eb_lookup_vmas(struct i915_execbuffer *eb)
 	i915_gem_object_put(obj);
 err_vma:
 	eb->vma[i] = NULL;
+err_ctx:
+	mutex_unlock(&eb->gem_context->mutex);
 	return err;
 }
 
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.c b/drivers/gpu/drm/i915/gem/i915_gem_object.c
index c178cf7614c6..29deae2eec93 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_object.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_object.c
@@ -127,39 +127,47 @@  void i915_gem_object_set_cache_coherency(struct drm_i915_gem_object *obj,
 
 void i915_gem_close_object(struct drm_gem_object *gem, struct drm_file *file)
 {
-	struct drm_i915_private *i915 = to_i915(gem->dev);
 	struct drm_i915_gem_object *obj = to_intel_bo(gem);
 	struct drm_i915_file_private *fpriv = file->driver_priv;
 	struct i915_lut_handle *lut, *ln;
+	LIST_HEAD(close);
 
-	mutex_lock(&i915->drm.struct_mutex);
-
+	i915_gem_object_lock(obj);
 	list_for_each_entry_safe(lut, ln, &obj->lut_list, obj_link) {
 		struct i915_gem_context *ctx = lut->ctx;
-		struct i915_vma *vma;
 
-		GEM_BUG_ON(ctx->file_priv == ERR_PTR(-EBADF));
 		if (ctx->file_priv != fpriv)
 			continue;
 
-		vma = radix_tree_delete(&ctx->handles_vma, lut->handle);
-		GEM_BUG_ON(vma->obj != obj);
+		i915_gem_context_get(ctx);
+		list_move(&lut->obj_link, &close);
+	}
+	i915_gem_object_unlock(obj);
+
+	list_for_each_entry_safe(lut, ln, &close, obj_link) {
+		struct i915_gem_context *ctx = lut->ctx;
+		struct i915_vma *vma;
 
-		/* We allow the process to have multiple handles to the same
+		/*
+		 * We allow the process to have multiple handles to the same
 		 * vma, in the same fd namespace, by virtue of flink/open.
 		 */
-		GEM_BUG_ON(!vma->open_count);
-		if (!--vma->open_count && !i915_vma_is_ggtt(vma))
-			i915_vma_close(vma);
 
-		list_del(&lut->obj_link);
-		list_del(&lut->ctx_link);
+		mutex_lock(&ctx->mutex);
+		vma = radix_tree_delete(&ctx->handles_vma, lut->handle);
+		if (vma) {
+			GEM_BUG_ON(vma->obj != obj);
+			GEM_BUG_ON(!atomic_read(&vma->open_count));
+			if (atomic_dec_and_test(&vma->open_count) &&
+			    !i915_vma_is_ggtt(vma))
+				i915_vma_close(vma);
+		}
+		mutex_unlock(&ctx->mutex);
 
+		i915_gem_context_put(lut->ctx);
 		i915_lut_handle_free(lut);
 		i915_gem_object_put(obj);
 	}
-
-	mutex_unlock(&i915->drm.struct_mutex);
 }
 
 static bool discard_backing_storage(struct drm_i915_gem_object *obj)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object_types.h b/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
index 133581339d81..4a5332662bf9 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
@@ -24,7 +24,6 @@  struct drm_i915_gem_object;
  */
 struct i915_lut_handle {
 	struct list_head obj_link;
-	struct list_head ctx_link;
 	struct i915_gem_context *ctx;
 	u32 handle;
 };
diff --git a/drivers/gpu/drm/i915/gem/selftests/mock_context.c b/drivers/gpu/drm/i915/gem/selftests/mock_context.c
index d373d7238622..080c44509ba9 100644
--- a/drivers/gpu/drm/i915/gem/selftests/mock_context.c
+++ b/drivers/gpu/drm/i915/gem/selftests/mock_context.c
@@ -30,7 +30,6 @@  mock_context(struct drm_i915_private *i915,
 	RCU_INIT_POINTER(ctx->engines, e);
 
 	INIT_RADIX_TREE(&ctx->handles_vma, GFP_KERNEL);
-	INIT_LIST_HEAD(&ctx->handles_list);
 	INIT_LIST_HEAD(&ctx->hw_id_link);
 	mutex_init(&ctx->mutex);
 
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index dcfc8a54d63c..e328b8dd8f47 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -2000,10 +2000,12 @@  struct drm_i915_private {
 		} timelines;
 
 		struct list_head active_rings;
-		struct list_head closed_vma;
 
 		struct intel_wakeref wakeref;
 
+		struct list_head closed_vma;
+		spinlock_t closed_lock; /* guards the list of closed_vma */
+
 		/**
 		 * Is the GPU currently considered idle, or busy executing
 		 * userspace requests? Whilst idle, we allow runtime power
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 2a9e8ecf2926..90923fa6603d 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -1732,6 +1732,7 @@  int i915_gem_init_early(struct drm_i915_private *dev_priv)
 
 	INIT_LIST_HEAD(&dev_priv->gt.active_rings);
 	INIT_LIST_HEAD(&dev_priv->gt.closed_vma);
+	spin_lock_init(&dev_priv->gt.closed_lock);
 
 	i915_gem_init__mm(dev_priv);
 	i915_gem_init__pm(dev_priv);
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 56be4b091bc7..f26eaa81e7fa 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -1929,6 +1929,7 @@  static struct i915_vma *pd_vma_create(struct gen6_hw_ppgtt *ppgtt, int size)
 	vma->ggtt_view.type = I915_GGTT_VIEW_ROTATED; /* prevent fencing */
 
 	INIT_LIST_HEAD(&vma->obj_link);
+	INIT_LIST_HEAD(&vma->closed_link);
 
 	mutex_lock(&vma->vm->mutex);
 	list_add(&vma->vm_link, &vma->vm->unbound_list);
diff --git a/drivers/gpu/drm/i915/i915_timeline.c b/drivers/gpu/drm/i915/i915_timeline.c
index 5fbea0892f33..000e1a9b6750 100644
--- a/drivers/gpu/drm/i915/i915_timeline.c
+++ b/drivers/gpu/drm/i915/i915_timeline.c
@@ -61,7 +61,7 @@  hwsp_alloc(struct i915_timeline *timeline, unsigned int *cacheline)
 
 	BUILD_BUG_ON(BITS_PER_TYPE(u64) * CACHELINE_BYTES > PAGE_SIZE);
 
-	spin_lock(&gt->hwsp_lock);
+	spin_lock_irq(&gt->hwsp_lock);
 
 	/* hwsp_free_list only contains HWSP that have available cachelines */
 	hwsp = list_first_entry_or_null(&gt->hwsp_free_list,
@@ -69,7 +69,7 @@  hwsp_alloc(struct i915_timeline *timeline, unsigned int *cacheline)
 	if (!hwsp) {
 		struct i915_vma *vma;
 
-		spin_unlock(&gt->hwsp_lock);
+		spin_unlock_irq(&gt->hwsp_lock);
 
 		hwsp = kmalloc(sizeof(*hwsp), GFP_KERNEL);
 		if (!hwsp)
@@ -86,7 +86,7 @@  hwsp_alloc(struct i915_timeline *timeline, unsigned int *cacheline)
 		hwsp->free_bitmap = ~0ull;
 		hwsp->gt = gt;
 
-		spin_lock(&gt->hwsp_lock);
+		spin_lock_irq(&gt->hwsp_lock);
 		list_add(&hwsp->free_link, &gt->hwsp_free_list);
 	}
 
@@ -96,7 +96,7 @@  hwsp_alloc(struct i915_timeline *timeline, unsigned int *cacheline)
 	if (!hwsp->free_bitmap)
 		list_del(&hwsp->free_link);
 
-	spin_unlock(&gt->hwsp_lock);
+	spin_unlock_irq(&gt->hwsp_lock);
 
 	GEM_BUG_ON(hwsp->vma->private != hwsp);
 	return hwsp->vma;
@@ -105,8 +105,9 @@  hwsp_alloc(struct i915_timeline *timeline, unsigned int *cacheline)
 static void __idle_hwsp_free(struct i915_timeline_hwsp *hwsp, int cacheline)
 {
 	struct i915_gt_timelines *gt = hwsp->gt;
+	unsigned long flags;
 
-	spin_lock(&gt->hwsp_lock);
+	spin_lock_irqsave(&gt->hwsp_lock, flags);
 
 	/* As a cacheline becomes available, publish the HWSP on the freelist */
 	if (!hwsp->free_bitmap)
@@ -122,7 +123,7 @@  static void __idle_hwsp_free(struct i915_timeline_hwsp *hwsp, int cacheline)
 		kfree(hwsp);
 	}
 
-	spin_unlock(&gt->hwsp_lock);
+	spin_unlock_irqrestore(&gt->hwsp_lock, flags);
 }
 
 static void __idle_cacheline_free(struct i915_timeline_cacheline *cl)
diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c
index 16d47f1f645a..392c2757c217 100644
--- a/drivers/gpu/drm/i915/i915_vma.c
+++ b/drivers/gpu/drm/i915/i915_vma.c
@@ -143,6 +143,8 @@  vma_create(struct drm_i915_gem_object *obj,
 	vma->size = obj->base.size;
 	vma->display_alignment = I915_GTT_MIN_ALIGNMENT;
 
+	INIT_LIST_HEAD(&vma->closed_link);
+
 	if (view && view->type != I915_GGTT_VIEW_NORMAL) {
 		vma->ggtt_view = *view;
 		if (view->type == I915_GGTT_VIEW_PARTIAL) {
@@ -785,10 +787,10 @@  int __i915_vma_do_pin(struct i915_vma *vma,
 
 void i915_vma_close(struct i915_vma *vma)
 {
-	lockdep_assert_held(&vma->vm->i915->drm.struct_mutex);
+	struct drm_i915_private *i915 = vma->vm->i915;
+	unsigned long flags;
 
 	GEM_BUG_ON(i915_vma_is_closed(vma));
-	vma->flags |= I915_VMA_CLOSED;
 
 	/*
 	 * We defer actually closing, unbinding and destroying the VMA until
@@ -802,17 +804,26 @@  void i915_vma_close(struct i915_vma *vma)
 	 * causing us to rebind the VMA once more. This ends up being a lot
 	 * of wasted work for the steady state.
 	 */
-	list_add_tail(&vma->closed_link, &vma->vm->i915->gt.closed_vma);
+	spin_lock_irqsave(&i915->gt.closed_lock, flags);
+	list_add(&vma->closed_link, &i915->gt.closed_vma);
+	spin_unlock_irqrestore(&i915->gt.closed_lock, flags);
 }
 
-void i915_vma_reopen(struct i915_vma *vma)
+static void __i915_vma_remove_closed(struct i915_vma *vma)
 {
-	lockdep_assert_held(&vma->vm->i915->drm.struct_mutex);
+	struct drm_i915_private *i915 = vma->vm->i915;
 
-	if (vma->flags & I915_VMA_CLOSED) {
-		vma->flags &= ~I915_VMA_CLOSED;
-		list_del(&vma->closed_link);
-	}
+	if (!i915_vma_is_closed(vma))
+		return;
+
+	spin_lock_irq(&i915->gt.closed_lock);
+	list_del_init(&vma->closed_link);
+	spin_unlock_irq(&i915->gt.closed_lock);
+}
+
+void i915_vma_reopen(struct i915_vma *vma)
+{
+	__i915_vma_remove_closed(vma);
 }
 
 static void __i915_vma_destroy(struct i915_vma *vma)
@@ -846,8 +857,7 @@  void i915_vma_destroy(struct i915_vma *vma)
 
 	GEM_BUG_ON(i915_vma_is_pinned(vma));
 
-	if (i915_vma_is_closed(vma))
-		list_del(&vma->closed_link);
+	__i915_vma_remove_closed(vma);
 
 	WARN_ON(i915_vma_unbind(vma));
 	GEM_BUG_ON(i915_vma_is_active(vma));
@@ -859,12 +869,16 @@  void i915_vma_parked(struct drm_i915_private *i915)
 {
 	struct i915_vma *vma, *next;
 
+	spin_lock_irq(&i915->gt.closed_lock);
 	list_for_each_entry_safe(vma, next, &i915->gt.closed_vma, closed_link) {
-		GEM_BUG_ON(!i915_vma_is_closed(vma));
+		list_del_init(&vma->closed_link);
+		spin_unlock_irq(&i915->gt.closed_lock);
+
 		i915_vma_destroy(vma);
-	}
 
-	GEM_BUG_ON(!list_empty(&i915->gt.closed_vma));
+		spin_lock_irq(&i915->gt.closed_lock);
+	}
+	spin_unlock_irq(&i915->gt.closed_lock);
 }
 
 static void __i915_vma_iounmap(struct i915_vma *vma)
diff --git a/drivers/gpu/drm/i915/i915_vma.h b/drivers/gpu/drm/i915/i915_vma.h
index 71ac7ee8620a..f0884cc8b2d3 100644
--- a/drivers/gpu/drm/i915/i915_vma.h
+++ b/drivers/gpu/drm/i915/i915_vma.h
@@ -69,7 +69,7 @@  struct i915_vma {
 	 * handles (but same file) for execbuf, i.e. the number of aliases
 	 * that exist in the ctx->handle_vmas LUT for this vma.
 	 */
-	unsigned int open_count;
+	atomic_t open_count;
 	unsigned long flags;
 	/**
 	 * How many users have pinned this object in GTT space.
@@ -104,10 +104,9 @@  struct i915_vma {
 
 #define I915_VMA_GGTT		BIT(11)
 #define I915_VMA_CAN_FENCE	BIT(12)
-#define I915_VMA_CLOSED		BIT(13)
-#define I915_VMA_USERFAULT_BIT	14
+#define I915_VMA_USERFAULT_BIT	13
 #define I915_VMA_USERFAULT	BIT(I915_VMA_USERFAULT_BIT)
-#define I915_VMA_GGTT_WRITE	BIT(15)
+#define I915_VMA_GGTT_WRITE	BIT(14)
 
 	struct i915_active active;
 	struct i915_active_request last_fence;
@@ -190,11 +189,6 @@  static inline bool i915_vma_is_map_and_fenceable(const struct i915_vma *vma)
 	return vma->flags & I915_VMA_CAN_FENCE;
 }
 
-static inline bool i915_vma_is_closed(const struct i915_vma *vma)
-{
-	return vma->flags & I915_VMA_CLOSED;
-}
-
 static inline bool i915_vma_set_userfault(struct i915_vma *vma)
 {
 	GEM_BUG_ON(!i915_vma_is_map_and_fenceable(vma));
@@ -211,6 +205,11 @@  static inline bool i915_vma_has_userfault(const struct i915_vma *vma)
 	return test_bit(I915_VMA_USERFAULT_BIT, &vma->flags);
 }
 
+static inline bool i915_vma_is_closed(const struct i915_vma *vma)
+{
+	return !list_empty(&vma->closed_link);
+}
+
 static inline u32 i915_ggtt_offset(const struct i915_vma *vma)
 {
 	GEM_BUG_ON(!i915_vma_is_ggtt(vma));
diff --git a/drivers/gpu/drm/i915/selftests/mock_gem_device.c b/drivers/gpu/drm/i915/selftests/mock_gem_device.c
index 576bb11b7858..ca8d73e6414e 100644
--- a/drivers/gpu/drm/i915/selftests/mock_gem_device.c
+++ b/drivers/gpu/drm/i915/selftests/mock_gem_device.c
@@ -204,6 +204,7 @@  struct drm_i915_private *mock_gem_device(void)
 
 	INIT_LIST_HEAD(&i915->gt.active_rings);
 	INIT_LIST_HEAD(&i915->gt.closed_vma);
+	spin_lock_init(&i915->gt.closed_lock);
 
 	mutex_lock(&i915->drm.struct_mutex);