drm/i915: The return of i915_gpu_info to debugfs

Once upon a time before we had automated GPU state capture upon hangs,
we had intel_gpu_dump. Now we come almost full circle and reinstate that
view of the current GPU queues and registers by using the error capture
facility to snapshot the GPU state when debugfs/.../i915_gpu_info is
opened - which should provided useful debugging to both the error
capture routines (without having to cause a hang and avoid the error
state being eaten by igt) and generally.

v2: Rename drm_i915_error_state to i915_gpu_state to alleviate some name
collisions between the error state dump and inspecting the gpu state.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170214164611.11381-1-chris@chris-wilson.co.uk

1 files changed, 10 insertions, 16 deletions

diff --git a/drivers/gpu/drm/i915/i915_sysfs.c b/drivers/gpu/drm/i915/i915_sysfs.c
index a721ff1..af0ac9f 100644
--- a/drivers/gpu/drm/i915/i915_sysfs.c
+++ b/drivers/gpu/drm/i915/i915_sysfs.c
@@ -522,33 +522,27 @@ static ssize_t error_state_read(struct file *filp, struct kobject *kobj,
 
 	struct device *kdev = kobj_to_dev(kobj);
 	struct drm_i915_private *dev_priv = kdev_minor_to_i915(kdev);
-	struct drm_device *dev = &dev_priv->drm;
-	struct i915_error_state_file_priv error_priv;
 	struct drm_i915_error_state_buf error_str;
-	ssize_t ret_count = 0;
-	int ret;
-
-	memset(&error_priv, 0, sizeof(error_priv));
+	struct i915_gpu_state *gpu;
+	ssize_t ret;
 
-	ret = i915_error_state_buf_init(&error_str, to_i915(dev), count, off);
+	ret = i915_error_state_buf_init(&error_str, dev_priv, count, off);
 	if (ret)
 		return ret;
 
-	error_priv.i915 = dev_priv;
-	i915_error_state_get(dev, &error_priv);
-
-	ret = i915_error_state_to_str(&error_str, &error_priv);
+	gpu = i915_first_error_state(dev_priv);
+	ret = i915_error_state_to_str(&error_str, gpu);
 	if (ret)
 		goto out;
 
-	ret_count = count < error_str.bytes ? count : error_str.bytes;
+	ret = count < error_str.bytes ? count : error_str.bytes;
+	memcpy(buf, error_str.buf, ret);
 
-	memcpy(buf, error_str.buf, ret_count);
 out:
-	i915_error_state_put(&error_priv);
+	i915_gpu_state_put(gpu);
 	i915_error_state_buf_release(&error_str);
 
-	return ret ?: ret_count;
+	return ret;
 }
 
 static ssize_t error_state_write(struct file *file, struct kobject *kobj,
@@ -559,7 +553,7 @@ static ssize_t error_state_write(struct file *file, struct kobject *kobj,
 	struct drm_i915_private *dev_priv = kdev_minor_to_i915(kdev);
 
 	DRM_DEBUG_DRIVER("Resetting error state\n");
-	i915_destroy_error_state(dev_priv);
+	i915_reset_error_state(dev_priv);
 
 	return count;
 }