drm: Clean up pending events in the core

There's really no reason to not do so, instead of replicating this
for every use-case and every driver. Now we can't just nuke the events,
since that would still mean that all drm_event users would need to know
when that has happened, since calling e.g. drm_send_event isn't allowed
any more. Instead just unlink them from the file, and detect this case
and handle it appropriately in all functions.

v2: Adjust existing kerneldoc too.

v3: Improve wording of the kerneldoc and split out vblank cleanup (Laurent).

Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Daniel Stone <daniels@collabora.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com> (v1)
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1453756616-28942-2-git-send-email-daniel.vetter@ffwll.ch
This commit is contained in:
Daniel Vetter 2016-01-25 22:16:43 +01:00
parent 4020b220ed
commit 681047b486
2 changed files with 31 additions and 1 deletions

View File

@ -264,6 +264,7 @@ static int drm_open_helper(struct file *filp, struct drm_minor *minor)
INIT_LIST_HEAD(&priv->fbs);
mutex_init(&priv->fbs_lock);
INIT_LIST_HEAD(&priv->blobs);
INIT_LIST_HEAD(&priv->pending_event_list);
INIT_LIST_HEAD(&priv->event_list);
init_waitqueue_head(&priv->event_wait);
priv->event_space = 4096; /* set aside 4k for event buffer */
@ -366,6 +367,13 @@ static void drm_events_release(struct drm_file *file_priv)
v->base.destroy(&v->base);
}
/* Unlink pending events */
list_for_each_entry_safe(e, et, &file_priv->pending_event_list,
pending_link) {
list_del(&e->pending_link);
e->file_priv = NULL;
}
/* Remove unconsumed events */
list_for_each_entry_safe(e, et, &file_priv->event_list, link) {
list_del(&e->link);
@ -712,6 +720,7 @@ int drm_event_reserve_init_locked(struct drm_device *dev,
file_priv->event_space -= e->length;
p->event = e;
list_add(&p->pending_link, &file_priv->pending_event_list);
p->file_priv = file_priv;
/* we *could* pass this in as arg, but everyone uses kfree: */
@ -774,7 +783,10 @@ void drm_event_cancel_free(struct drm_device *dev,
{
unsigned long flags;
spin_lock_irqsave(&dev->event_lock, flags);
p->file_priv->event_space += p->event->length;
if (p->file_priv) {
p->file_priv->event_space += p->event->length;
list_del(&p->pending_link);
}
spin_unlock_irqrestore(&dev->event_lock, flags);
p->destroy(p);
}
@ -788,11 +800,22 @@ EXPORT_SYMBOL(drm_event_cancel_free);
* This function sends the event @e, initialized with drm_event_reserve_init(),
* to its associated userspace DRM file. Callers must already hold
* dev->event_lock, see drm_send_event() for the unlocked version.
*
* Note that the core will take care of unlinking and disarming events when the
* corresponding DRM file is closed. Drivers need not worry about whether the
* DRM file for this event still exists and can call this function upon
* completion of the asynchronous work unconditionally.
*/
void drm_send_event_locked(struct drm_device *dev, struct drm_pending_event *e)
{
assert_spin_locked(&dev->event_lock);
if (!e->file_priv) {
e->destroy(e);
return;
}
list_del(&e->pending_link);
list_add_tail(&e->link,
&e->file_priv->event_list);
wake_up_interruptible(&e->file_priv->event_wait);
@ -807,6 +830,11 @@ EXPORT_SYMBOL(drm_send_event_locked);
* This function sends the event @e, initialized with drm_event_reserve_init(),
* to its associated userspace DRM file. This function acquires dev->event_lock,
* see drm_send_event_locked() for callers which already hold this lock.
*
* Note that the core will take care of unlinking and disarming events when the
* corresponding DRM file is closed. Drivers need not worry about whether the
* DRM file for this event still exists and can call this function upon
* completion of the asynchronous work unconditionally.
*/
void drm_send_event(struct drm_device *dev, struct drm_pending_event *e)
{

View File

@ -283,6 +283,7 @@ struct drm_ioctl_desc {
struct drm_pending_event {
struct drm_event *event;
struct list_head link;
struct list_head pending_link;
struct drm_file *file_priv;
pid_t pid; /* pid of requester, no guarantee it's valid by the time
we deliver the event, for tracing only */
@ -346,6 +347,7 @@ struct drm_file {
struct list_head blobs;
wait_queue_head_t event_wait;
struct list_head pending_event_list;
struct list_head event_list;
int event_space;