@@ -384,6 +384,9 @@ typedef struct drm_i915_private {
*/
struct list_head inactive_list;
+ /** LRU list of objects with fence regs on them. */
+ struct list_head fence_list;
+
/**
* List of breadcrumbs associated with GPU requests currently
* outstanding.
@@ -451,6 +454,9 @@ struct drm_i915_gem_object {
/** This object's place on the active/flushing/inactive lists */
struct list_head list;
+ /** This object's place on the fenced object LRU */
+ struct list_head fence_list;
+
/**
* This is set if the object is on the active or flushing lists
* (has pending rendering), and is not set if it's on inactive (ready
@@ -978,6 +978,7 @@ int
i915_gem_set_domain_ioctl(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
+ struct drm_i915_private *dev_priv = dev->dev_private;
struct drm_i915_gem_set_domain *args = data;
struct drm_gem_object *obj;
uint32_t read_domains = args->read_domains;
@@ -1010,8 +1011,18 @@ i915_gem_set_domain_ioctl(struct drm_device *dev, void *data,
obj, obj->size, read_domains, write_domain);
#endif
if (read_domains & I915_GEM_DOMAIN_GTT) {
+ struct drm_i915_gem_object *obj_priv = obj->driver_private;
+
ret = i915_gem_object_set_to_gtt_domain(obj, write_domain != 0);
+ /* Update the LRU on the fence for the CPU access that's
+ * about to occur.
+ */
+ if (obj_priv->fence_reg != I915_FENCE_REG_NONE) {
+ list_move_tail(&obj_priv->fence_list,
+ &dev_priv->mm.fence_list);
+ }
+
/* Silently promote "you're not bound, there was nothing to do"
* to success, since the client was just asking us to
* make sure everything was done.
@@ -1155,8 +1166,7 @@ int i915_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
}
/* Need a new fence register? */
- if (obj_priv->fence_reg == I915_FENCE_REG_NONE &&
- obj_priv->tiling_mode != I915_TILING_NONE) {
+ if (obj_priv->tiling_mode != I915_TILING_NONE) {
ret = i915_gem_object_get_fence_reg(obj);
if (ret) {
mutex_unlock(&dev->struct_mutex);
@@ -2208,6 +2218,12 @@ i915_gem_object_get_fence_reg(struct drm_gem_object *obj)
struct drm_i915_gem_object *old_obj_priv = NULL;
int i, ret, avail;
+ /* Just update our place in the LRU if our fence is getting used. */
+ if (obj_priv->fence_reg != I915_FENCE_REG_NONE) {
+ list_move_tail(&obj_priv->fence_list, &dev_priv->mm.fence_list);
+ return 0;
+ }
+
switch (obj_priv->tiling_mode) {
case I915_TILING_NONE:
WARN(1, "allocating a fence for non-tiled object?\n");
@@ -2229,7 +2245,6 @@ i915_gem_object_get_fence_reg(struct drm_gem_object *obj)
}
/* First try to find a free reg */
-try_again:
avail = 0;
for (i = dev_priv->fence_reg_start; i < dev_priv->num_fence_regs; i++) {
reg = &dev_priv->fence_regs[i];
@@ -2243,52 +2258,41 @@ try_again:
/* None available, try to steal one or wait for a user to finish */
if (i == dev_priv->num_fence_regs) {
- uint32_t seqno = dev_priv->mm.next_gem_seqno;
+ struct drm_gem_object *old_obj = NULL;
if (avail == 0)
return -ENOSPC;
- for (i = dev_priv->fence_reg_start;
- i < dev_priv->num_fence_regs; i++) {
- uint32_t this_seqno;
+ list_for_each_entry(old_obj_priv, &dev_priv->mm.fence_list,
+ fence_list) {
+ old_obj = old_obj_priv->obj;
- reg = &dev_priv->fence_regs[i];
- old_obj_priv = reg->obj->driver_private;
+ reg = &dev_priv->fence_regs[old_obj_priv->fence_reg];
if (old_obj_priv->pin_count)
continue;
+ /* Take a reference, as otherwise the wait_rendering
+ * below may cause the object to get freed out from
+ * under us.
+ */
+ drm_gem_object_reference(old_obj);
+
/* i915 uses fences for GPU access to tiled buffers */
if (IS_I965G(dev) || !old_obj_priv->active)
break;
- /* find the seqno of the first available fence */
- this_seqno = old_obj_priv->last_rendering_seqno;
- if (this_seqno != 0 &&
- reg->obj->write_domain == 0 &&
- i915_seqno_passed(seqno, this_seqno))
- seqno = this_seqno;
- }
-
- /*
- * Now things get ugly... we have to wait for one of the
- * objects to finish before trying again.
- */
- if (i == dev_priv->num_fence_regs) {
- if (seqno == dev_priv->mm.next_gem_seqno) {
- i915_gem_flush(dev,
- I915_GEM_GPU_DOMAINS,
- I915_GEM_GPU_DOMAINS);
- seqno = i915_add_request(dev, NULL,
- I915_GEM_GPU_DOMAINS);
- if (seqno == 0)
- return -ENOMEM;
- }
-
- ret = i915_wait_request(dev, seqno);
- if (ret)
+ /* This brings the object to the head of the LRU if it
+ * had been written to. The only way this should
+ * result in us waiting longer than the expected
+ * optimal amount of time is if there was a
+ * fence-using buffer later that was read-only.
+ */
+ i915_gem_object_flush_gpu_write_domain(old_obj);
+ ret = i915_gem_object_wait_rendering(old_obj);
+ if (ret != 0)
return ret;
- goto try_again;
+ break;
}
/*
@@ -2296,10 +2300,15 @@ try_again:
* for this object next time we need it.
*/
i915_gem_release_mmap(reg->obj);
+ i = old_obj_priv->fence_reg;
old_obj_priv->fence_reg = I915_FENCE_REG_NONE;
+ list_del_init(&old_obj_priv->fence_list);
+ drm_gem_object_unreference(old_obj);
}
obj_priv->fence_reg = i;
+ list_add_tail(&obj_priv->fence_list, &dev_priv->mm.fence_list);
+
reg->obj = obj;
if (IS_I965G(dev))
@@ -2342,6 +2351,7 @@ i915_gem_clear_fence_reg(struct drm_gem_object *obj)
dev_priv->fence_regs[obj_priv->fence_reg].obj = NULL;
obj_priv->fence_reg = I915_FENCE_REG_NONE;
+ list_del_init(&obj_priv->fence_list);
}
/**
@@ -3595,9 +3605,7 @@ i915_gem_object_pin(struct drm_gem_object *obj, uint32_t alignment)
* Pre-965 chips need a fence register set up in order to
* properly handle tiled surfaces.
*/
- if (!IS_I965G(dev) &&
- obj_priv->fence_reg == I915_FENCE_REG_NONE &&
- obj_priv->tiling_mode != I915_TILING_NONE) {
+ if (!IS_I965G(dev) && obj_priv->tiling_mode != I915_TILING_NONE) {
ret = i915_gem_object_get_fence_reg(obj);
if (ret != 0) {
if (ret != -EBUSY && ret != -ERESTARTSYS)
@@ -3806,6 +3814,7 @@ int i915_gem_init_object(struct drm_gem_object *obj)
obj_priv->obj = obj;
obj_priv->fence_reg = I915_FENCE_REG_NONE;
INIT_LIST_HEAD(&obj_priv->list);
+ INIT_LIST_HEAD(&obj_priv->fence_list);
return 0;
}
@@ -4253,6 +4262,7 @@ i915_gem_load(struct drm_device *dev)
INIT_LIST_HEAD(&dev_priv->mm.flushing_list);
INIT_LIST_HEAD(&dev_priv->mm.inactive_list);
INIT_LIST_HEAD(&dev_priv->mm.request_list);
+ INIT_LIST_HEAD(&dev_priv->mm.fence_list);
INIT_DELAYED_WORK(&dev_priv->mm.retire_work,
i915_gem_retire_work_handler);
dev_priv->mm.next_gem_seqno = 1;