[Intel-gfx] [PATCH] drm/i915: When evicting something fails, try unpinning old contexts and framebuffers

[Chris Wilson]

Before declaring that we cannot fit an object into the aperture, we
should first check if we can clear the aperture of pinned objects that
are now idle. These pinned objects include old hardware contexts and old
scanout buffers.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_gem.c       |  1 +
 drivers/gpu/drm/i915/i915_gem_evict.c | 11 ++++++++---
 drivers/gpu/drm/i915/intel_display.c  |  8 ++++++++
 drivers/gpu/drm/i915/intel_drv.h      |  1 +
 4 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index a99aaff1656a..8756a44774a2 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -2921,6 +2921,7 @@ int i915_gpu_idle(struct drm_device *dev)
 			return ret;
 	}
 
+	intel_wait_for_pending_flips(dev);
 	return 0;
 }
 
diff --git a/drivers/gpu/drm/i915/i915_gem_evict.c b/drivers/gpu/drm/i915/i915_gem_evict.c
index b7376533633d..a66b82dac2f8 100644
--- a/drivers/gpu/drm/i915/i915_gem_evict.c
+++ b/drivers/gpu/drm/i915/i915_gem_evict.c
@@ -80,6 +80,7 @@ i915_gem_evict_something(struct drm_device *dev, struct i915_address_space *vm,
 	 */
 
 	INIT_LIST_HEAD(&unwind_list);
+search_again:
 	if (mappable) {
 		BUG_ON(!i915_is_ggtt(vm));
 		drm_mm_init_scan_with_range(&vm->mm, min_size,
@@ -115,10 +116,14 @@ none:
 		list_del_init(&vma->exec_list);
 	}
 
-	/* We expect the caller to unpin, evict all and try again, or give up.
-	 * So calling i915_gem_evict_vm() is unnecessary.
+	/* Can we unpin some objects such as idle hw contents,
+	 * or pending flips?
 	 */
-	return -ENOSPC;
+	ret = nonblocking ? -ENOSPC : i915_gpu_idle(dev);
+	if (ret)
+		return ret;
+
+	goto search_again;
 
 found:
 	/* drm_mm doesn't allow any other other operations while
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index fe4c5f055973..10d677a1ae2f 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -2983,6 +2983,14 @@ static void intel_crtc_wait_for_pending_flips(struct drm_crtc *crtc)
 	mutex_unlock(&dev->struct_mutex);
 }
 
+void intel_wait_for_pending_flips(struct drm_device *dev)
+{
+	struct drm_crtc *crtc;
+
+	list_for_each_entry(crtc, &dev->mode_config.crtc_list, head)
+		intel_crtc_wait_for_pending_flips(crtc);
+}
+
 /* Program iCLKIP clock to the desired frequency */
 static void lpt_program_iclkip(struct drm_crtc *crtc)
 {
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 2b5bcb617908..e8fd10aa07ea 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -648,6 +648,7 @@ enum transcoder intel_pipe_to_cpu_transcoder(struct drm_i915_private *dev_priv,
 					     enum pipe pipe);
 void intel_wait_for_vblank(struct drm_device *dev, int pipe);
 void intel_wait_for_pipe_off(struct drm_device *dev, int pipe);
+void intel_wait_for_pending_flips(struct drm_device *dev);
 int ironlake_get_lanes_required(int target_clock, int link_bw, int bpp);
 void vlv_wait_port_ready(struct drm_i915_private *dev_priv,
 			 struct intel_digital_port *dport);
-- 
1.8.5.1