drm/i915: More accurately track last fence usage by the GPU

Based on a patch by Daniel Vetter.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index addb939..5faae47 100644 (file)
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -110,7 +110,7 @@ static const char *get_tiling_flag(struct drm_i915_gem_object *obj)
 static void
 describe_obj(struct seq_file *m, struct drm_i915_gem_object *obj)
 {
-       seq_printf(m, "%p: %s%s %8zd %08x %08x %d%s%s",
+       seq_printf(m, "%p: %s%s %8zd %04x %04x %d %d%s%s",
                   &obj->base,
                   get_pin_flag(obj),
                   get_tiling_flag(obj),
@@ -118,6 +118,7 @@ describe_obj(struct seq_file *m, struct drm_i915_gem_object *obj)
                   obj->base.read_domains,
                   obj->base.write_domain,
                   obj->last_rendering_seqno,
+                  obj->last_fenced_seqno,
                   obj->dirty ? " dirty" : "",
                   obj->madv == I915_MADV_DONTNEED ? " purgeable" : "");
        if (obj->base.name)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 42d3e90..ee7df1d 100644 (file)
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -124,9 +124,8 @@ struct drm_i915_master_private {
 #define I915_FENCE_REG_NONE -1
 
 struct drm_i915_fence_reg {
-       struct drm_i915_gem_object *obj;
        struct list_head lru_list;
-       bool gpu;
+       struct drm_i915_gem_object *obj;
 };
 
 struct sdvo_device_mapping {
@@ -787,6 +786,12 @@ struct drm_i915_gem_object {
        unsigned int fault_mappable : 1;
        unsigned int pin_mappable : 1;
 
+       /*
+        * Is the GPU currently using a fence to access this buffer,
+        */
+       unsigned int pending_fenced_gpu_access:1;
+       unsigned int fenced_gpu_access:1;
+
        struct page **pages;
 
        /**
@@ -802,11 +807,13 @@ struct drm_i915_gem_object {
         */
        uint32_t gtt_offset;
 
-       /* Which ring is refering to is this object */
-       struct intel_ring_buffer *ring;
-
        /** Breadcrumb of last rendering to the buffer. */
        uint32_t last_rendering_seqno;
+       struct intel_ring_buffer *ring;
+
+       /** Breadcrumb of last fenced GPU access to the buffer. */
+       uint32_t last_fenced_seqno;
+       struct intel_ring_buffer *last_fenced_ring;
 
        /** Current tiling stride for the object, if it's tiled. */
        uint32_t stride;

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 061426e..2cfdee8 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -1688,7 +1688,27 @@ i915_gem_object_move_to_active(struct drm_i915_gem_object *obj,
        /* Move from whatever list we were on to the tail of execution. */
        list_move_tail(&obj->mm_list, &dev_priv->mm.active_list);
        list_move_tail(&obj->ring_list, &ring->active_list);
+
        obj->last_rendering_seqno = seqno;
+       if (obj->fenced_gpu_access) {
+               struct drm_i915_fence_reg *reg;
+
+               BUG_ON(obj->fence_reg == I915_FENCE_REG_NONE);
+
+               obj->last_fenced_seqno = seqno;
+               obj->last_fenced_ring = ring;
+
+               reg = &dev_priv->fence_regs[obj->fence_reg];
+               list_move_tail(&reg->lru_list, &dev_priv->mm.fence_list);
+       }
+}
+
+static void
+i915_gem_object_move_off_active(struct drm_i915_gem_object *obj)
+{
+       list_del_init(&obj->ring_list);
+       obj->last_rendering_seqno = 0;
+       obj->last_fenced_seqno = 0;
 }
 
 static void
@@ -1699,8 +1719,33 @@ i915_gem_object_move_to_flushing(struct drm_i915_gem_object *obj)
 
        BUG_ON(!obj->active);
        list_move_tail(&obj->mm_list, &dev_priv->mm.flushing_list);
-       list_del_init(&obj->ring_list);
-       obj->last_rendering_seqno = 0;
+
+       i915_gem_object_move_off_active(obj);
+}
+
+static void
+i915_gem_object_move_to_inactive(struct drm_i915_gem_object *obj)
+{
+       struct drm_device *dev = obj->base.dev;
+       struct drm_i915_private *dev_priv = dev->dev_private;
+
+       if (obj->pin_count != 0)
+               list_move_tail(&obj->mm_list, &dev_priv->mm.pinned_list);
+       else
+               list_move_tail(&obj->mm_list, &dev_priv->mm.inactive_list);
+
+       BUG_ON(!list_empty(&obj->gpu_write_list));
+       BUG_ON(!obj->active);
+       obj->ring = NULL;
+
+       i915_gem_object_move_off_active(obj);
+       obj->fenced_gpu_access = false;
+       obj->last_fenced_ring = NULL;
+
+       obj->active = 0;
+       drm_gem_object_unreference(&obj->base);
+
+       WARN_ON(i915_verify_lists(dev));
 }
 
 /* Immediately discard the backing storage */
@@ -1729,35 +1774,11 @@ i915_gem_object_is_purgeable(struct drm_i915_gem_object *obj)
        return obj->madv == I915_MADV_DONTNEED;
 }
 
-static void
-i915_gem_object_move_to_inactive(struct drm_i915_gem_object *obj)
-{
-       struct drm_device *dev = obj->base.dev;
-       drm_i915_private_t *dev_priv = dev->dev_private;
-
-       if (obj->pin_count != 0)
-               list_move_tail(&obj->mm_list, &dev_priv->mm.pinned_list);
-       else
-               list_move_tail(&obj->mm_list, &dev_priv->mm.inactive_list);
-       list_del_init(&obj->ring_list);
-
-       BUG_ON(!list_empty(&obj->gpu_write_list));
-
-       obj->last_rendering_seqno = 0;
-       obj->ring = NULL;
-       if (obj->active) {
-               obj->active = 0;
-               drm_gem_object_unreference(&obj->base);
-       }
-       WARN_ON(i915_verify_lists(dev));
-}
-
 static void
 i915_gem_process_flushing_list(struct drm_device *dev,
                               uint32_t flush_domains,
                               struct intel_ring_buffer *ring)
 {
-       drm_i915_private_t *dev_priv = dev->dev_private;
        struct drm_i915_gem_object *obj, *next;
 
        list_for_each_entry_safe(obj, next,
@@ -1770,14 +1791,6 @@ i915_gem_process_flushing_list(struct drm_device *dev,
                        list_del_init(&obj->gpu_write_list);
                        i915_gem_object_move_to_active(obj, ring);
 
-                       /* update the fence lru list */
-                       if (obj->fence_reg != I915_FENCE_REG_NONE) {
-                               struct drm_i915_fence_reg *reg =
-                                       &dev_priv->fence_regs[obj->fence_reg];
-                               list_move_tail(&reg->lru_list,
-                                               &dev_priv->mm.fence_list);
-                       }
-
                        trace_i915_gem_object_change_domain(obj,
                                                            obj->base.read_domains,
                                                            old_write_domain);
@@ -2615,8 +2628,7 @@ i915_gem_object_put_fence_reg(struct drm_i915_gem_object *obj,
                              bool interruptible)
 {
        struct drm_device *dev = obj->base.dev;
-       struct drm_i915_private *dev_priv = dev->dev_private;
-       struct drm_i915_fence_reg *reg;
+       int ret;
 
        if (obj->fence_reg == I915_FENCE_REG_NONE)
                return 0;
@@ -2631,19 +2643,23 @@ i915_gem_object_put_fence_reg(struct drm_i915_gem_object *obj,
         * therefore we must wait for any outstanding access to complete
         * before clearing the fence.
         */
-       reg = &dev_priv->fence_regs[obj->fence_reg];
-       if (reg->gpu) {
-               int ret;
-
+       if (obj->fenced_gpu_access) {
                ret = i915_gem_object_flush_gpu_write_domain(obj, NULL);
                if (ret)
                        return ret;
 
-               ret = i915_gem_object_wait_rendering(obj, interruptible);
+               obj->fenced_gpu_access = false;
+       }
+
+       if (obj->last_fenced_seqno) {
+               ret = i915_do_wait_request(dev,
+                                          obj->last_fenced_seqno,
+                                          interruptible,
+                                          obj->last_fenced_ring);
                if (ret)
                        return ret;
 
-               reg->gpu = false;
+               obj->last_fenced_seqno = false;
        }
 
        i915_gem_object_flush_gtt_write_domain(obj);
@@ -3166,8 +3182,9 @@ i915_gem_object_set_to_gpu_domain(struct drm_i915_gem_object *obj,
         * write domain
         */
        if (obj->base.write_domain &&
-           (obj->base.write_domain != obj->base.pending_read_domains ||
-            obj->ring != ring)) {
+           (((obj->base.write_domain != obj->base.pending_read_domains ||
+              obj->ring != ring)) ||
+            (obj->fenced_gpu_access && !obj->pending_fenced_gpu_access))) {
                flush_domains |= obj->base.write_domain;
                invalidate_domains |=
                        obj->base.pending_read_domains & ~obj->base.write_domain;
@@ -3528,7 +3545,6 @@ i915_gem_execbuffer_reserve(struct drm_device *dev,
                            struct drm_i915_gem_exec_object2 *exec_list,
                            int count)
 {
-       struct drm_i915_private *dev_priv = dev->dev_private;
        int ret, i, retry;
 
        /* Attempt to pin all of the buffers into the GTT.
@@ -3601,7 +3617,7 @@ i915_gem_execbuffer_reserve(struct drm_device *dev,
                                if (ret)
                                        break;
 
-                               dev_priv->fence_regs[obj->fence_reg].gpu = true;
+                               obj->pending_fenced_gpu_access = true;
                        }
 
                        entry->offset = obj->gtt_offset;
@@ -3981,6 +3997,7 @@ i915_gem_do_execbuffer(struct drm_device *dev, void *data,
                        goto err;
                }
                obj->in_execbuffer = true;
+               obj->pending_fenced_gpu_access = false;
        }
 
        /* Move the objects en-masse into the GTT, evicting if necessary. */
@@ -4085,6 +4102,7 @@ i915_gem_do_execbuffer(struct drm_device *dev, void *data,
 
                obj->base.read_domains = obj->base.pending_read_domains;
                obj->base.write_domain = obj->base.pending_write_domain;
+               obj->fenced_gpu_access = obj->pending_fenced_gpu_access;
 
                i915_gem_object_move_to_active(obj, ring);
                if (obj->base.write_domain) {