drm: Include task->name and master status in debugfs clients info

Showing who is the current master is useful for trying to decypher
errors when trying to acquire master (e.g. a race with X taking over
from plymouth). By including the process name as well as the pid
simplifies the task of grabbing enough information remotely at the point
of error.

v2: Add the command column header and flesh out a couple of comments.
(David Herrmann)

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This commit is contained in:
Chris Wilson 2014-09-02 08:03:22 +01:00 committed by Daniel Vetter
parent 2a5706a36d
commit 50d47cb318

View file

@ -183,15 +183,32 @@ int drm_clients_info(struct seq_file *m, void *data)
struct drm_device *dev = node->minor->dev;
struct drm_file *priv;
seq_printf(m,
"%20s %5s %3s master a %5s %10s\n",
"command",
"pid",
"dev",
"uid",
"magic");
/* dev->filelist is sorted youngest first, but we want to present
* oldest first (i.e. kernel, servers, clients), so walk backwardss.
*/
mutex_lock(&dev->struct_mutex);
seq_printf(m, "a dev pid uid magic\n\n");
list_for_each_entry(priv, &dev->filelist, lhead) {
seq_printf(m, "%c %3d %5d %5d %10u\n",
priv->authenticated ? 'y' : 'n',
priv->minor->index,
list_for_each_entry_reverse(priv, &dev->filelist, lhead) {
struct task_struct *task;
rcu_read_lock(); /* locks pid_task()->comm */
task = pid_task(priv->pid, PIDTYPE_PID);
seq_printf(m, "%20s %5d %3d %c %c %5d %10u\n",
task ? task->comm : "<unknown>",
pid_vnr(priv->pid),
priv->minor->index,
priv->is_master ? 'y' : 'n',
priv->authenticated ? 'y' : 'n',
from_kuid_munged(seq_user_ns(m), priv->uid),
priv->magic);
rcu_read_unlock();
}
mutex_unlock(&dev->struct_mutex);
return 0;