drm/i915: allow the existing error_state to be destroyed
... by writing (anything) to i915_error_state.
This way we can simulate a bunch of gpu hangs and run the error_state
capture code every time (without the need to reload the module).
To make that happen we need to abandon the simple seq_file wrappers
provided by the drm core. While at it put the new error_state
refcounting to some good use and associated the error_state to the
debugfs when opening the file. Otherwise the error_state could change
while someone is reading it. This should help greatly when we finally
get around to split up the giant single seq_file block that the
error_state file currently is into smaller parts.
v2: Actually squash all the fixes into the patch ...
Reviewed-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 72c73de..950f72a 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -688,21 +688,19 @@
seq_printf(m, " ring->tail: 0x%08x\n", error->cpu_ring_tail[ring]);
}
+struct i915_error_state_file_priv {
+ struct drm_device *dev;
+ struct drm_i915_error_state *error;
+};
+
static int i915_error_state(struct seq_file *m, void *unused)
{
- struct drm_info_node *node = (struct drm_info_node *) m->private;
- struct drm_device *dev = node->minor->dev;
+ struct i915_error_state_file_priv *error_priv = m->private;
+ struct drm_device *dev = error_priv->dev;
drm_i915_private_t *dev_priv = dev->dev_private;
- struct drm_i915_error_state *error;
- unsigned long flags;
+ struct drm_i915_error_state *error = error_priv->error;
int i, j, page, offset, elt;
- spin_lock_irqsave(&dev_priv->error_lock, flags);
- error = dev_priv->first_error;
- if (error)
- kref_get(&error->ref);
- spin_unlock_irqrestore(&dev_priv->error_lock, flags);
-
if (!error) {
seq_printf(m, "no error state collected\n");
return 0;
@@ -790,11 +788,71 @@
if (error->display)
intel_display_print_error_state(m, dev, error->display);
- kref_put(&error->ref, i915_error_state_free);
-
return 0;
}
+static ssize_t
+i915_error_state_write(struct file *filp,
+ const char __user *ubuf,
+ size_t cnt,
+ loff_t *ppos)
+{
+ struct seq_file *m = filp->private_data;
+ struct i915_error_state_file_priv *error_priv = m->private;
+ struct drm_device *dev = error_priv->dev;
+
+ DRM_DEBUG_DRIVER("Resetting error state\n");
+
+ mutex_lock(&dev->struct_mutex);
+ i915_destroy_error_state(dev);
+ mutex_unlock(&dev->struct_mutex);
+
+ return cnt;
+}
+
+static int i915_error_state_open(struct inode *inode, struct file *file)
+{
+ struct drm_device *dev = inode->i_private;
+ drm_i915_private_t *dev_priv = dev->dev_private;
+ struct i915_error_state_file_priv *error_priv;
+ unsigned long flags;
+
+ error_priv = kzalloc(sizeof(*error_priv), GFP_KERNEL);
+ if (!error_priv)
+ return -ENOMEM;
+
+ error_priv->dev = dev;
+
+ spin_lock_irqsave(&dev_priv->error_lock, flags);
+ error_priv->error = dev_priv->first_error;
+ if (error_priv->error)
+ kref_get(&error_priv->error->ref);
+ spin_unlock_irqrestore(&dev_priv->error_lock, flags);
+
+ return single_open(file, i915_error_state, error_priv);
+}
+
+static int i915_error_state_release(struct inode *inode, struct file *file)
+{
+ struct seq_file *m = file->private_data;
+ struct i915_error_state_file_priv *error_priv = m->private;
+
+ if (error_priv->error)
+ kref_put(&error_priv->error->ref, i915_error_state_free);
+ kfree(error_priv);
+
+ return single_release(inode, file);
+}
+
+static const struct file_operations i915_error_state_fops = {
+ .owner = THIS_MODULE,
+ .open = i915_error_state_open,
+ .read = seq_read,
+ .write = i915_error_state_write,
+ .llseek = default_llseek,
+ .release = i915_error_state_release,
+};
+
static int i915_rstdby_delays(struct seq_file *m, void *unused)
{
struct drm_info_node *node = (struct drm_info_node *) m->private;
@@ -1646,6 +1704,7 @@
.write = i915_ring_stop_write,
.llseek = default_llseek,
};
+
static ssize_t
i915_max_freq_read(struct file *filp,
char __user *ubuf,
@@ -1900,7 +1959,6 @@
{"i915_gem_hws", i915_hws_info, 0, (void *)RCS},
{"i915_gem_hws_blt", i915_hws_info, 0, (void *)BCS},
{"i915_gem_hws_bsd", i915_hws_info, 0, (void *)VCS},
- {"i915_error_state", i915_error_state, 0},
{"i915_rstdby_delays", i915_rstdby_delays, 0},
{"i915_cur_delayinfo", i915_cur_delayinfo, 0},
{"i915_delayfreq_table", i915_delayfreq_table, 0},
@@ -1952,6 +2010,12 @@
if (ret)
return ret;
+ ret = i915_debugfs_create(minor->debugfs_root, minor,
+ "i915_error_state",
+ &i915_error_state_fops);
+ if (ret)
+ return ret;
+
return drm_debugfs_create_files(i915_debugfs_list,
I915_DEBUGFS_ENTRIES,
minor->debugfs_root, minor);