[PATCH 1/3] drm: Send pending vblank events before disabling vblank.

[christopher.halse.rog...@canonical.com]

From: Christopher James Halse Rogers 

This is the least-bad behaviour.  It means that we signal the
vblank event before it actually happens, but since we're disabling
vblanks there's no guarantee that it will *ever* happen otherwise.

This prevents GL applications which use WaitMSC from hanging
indefinitely.

Signed-off-by: Christopher James Halse Rogers 
---
 drivers/gpu/drm/drm_irq.c |   23 +++
 1 files changed, 23 insertions(+), 0 deletions(-)

diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index 741457b..a1f12cb 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -932,11 +932,34 @@ EXPORT_SYMBOL(drm_vblank_put);

 void drm_vblank_off(struct drm_device *dev, int crtc)
 {
+   struct drm_pending_vblank_event *e, *t;
+   struct timeval now;
unsigned long irqflags;
+   unsigned int seq;

spin_lock_irqsave(&dev->vbl_lock, irqflags);
vblank_disable_and_save(dev, crtc);
DRM_WAKEUP(&dev->vbl_queue[crtc]);
+
+   /* Send any queued vblank events, lest the natives grow disquiet */
+   seq = drm_vblank_count_and_time(dev, crtc, &now);
+   list_for_each_entry_safe(e, t, &dev->vblank_event_list, base.link) {
+   if (e->pipe != crtc)
+   continue;
+   DRM_DEBUG("Sending premature vblank event on disable: \
+ wanted %d, current %d\n",
+ e->event.sequence, seq);
+
+   e->event.sequence = seq;
+   e->event.tv_sec = now.tv_sec;
+   e->event.tv_usec = now.tv_usec;
+   drm_vblank_put(dev, e->pipe);
+   list_move_tail(&e->base.link, &e->base.file_priv->event_list);
+   wake_up_interruptible(&e->base.file_priv->event_wait);
+   trace_drm_vblank_event_delivered(e->base.pid, e->pipe,
+e->event.sequence);
+   }
+
spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
 }
 EXPORT_SYMBOL(drm_vblank_off);
-- 
1.7.4.1

[PATCH 2/3] drm: Warn if vblank state has become inconsistent.

[christopher.halse.rog...@canonical.com]

From: Christopher James Halse Rogers 

After emitting all the waiting vblank events no-one should hold
a vblank reference.  Emit a warning if this is not the case.

Signed-off-by: Christopher James Halse Rogers 
---
 drivers/gpu/drm/drm_irq.c |1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index a1f12cb..72407fa 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -960,6 +960,7 @@ void drm_vblank_off(struct drm_device *dev, int crtc)
 e->event.sequence);
}

+   WARN_ON(atomic_read(&dev->vblank_refcount[crtc]) != 0);
spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
 }
 EXPORT_SYMBOL(drm_vblank_off);
-- 
1.7.4.1

[PATCH 3/3] drm: Factor-out drm_emit_vblank_event code.

[christopher.halse.rog...@canonical.com]

From: Christopher James Halse Rogers 

Signed-off-by: Christopher James Halse Rogers 
---
 drivers/gpu/drm/drm_irq.c |   39 ---
 1 files changed, 16 insertions(+), 23 deletions(-)

diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index 72407fa..485714b 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -930,6 +930,18 @@ void drm_vblank_put(struct drm_device *dev, int crtc)
 }
 EXPORT_SYMBOL(drm_vblank_put);

+static void drm_emit_vblank_event (struct drm_pending_vblank_event *e,
+  unsigned int seq, struct timeval *now)
+{
+   e->event.sequence = seq;
+   e->event.tv_sec = now->tv_sec;
+   e->event.tv_usec = now->tv_usec;
+   list_move_tail(&e->base.link, &e->base.file_priv->event_list);
+   wake_up_interruptible(&e->base.file_priv->event_wait);
+   trace_drm_vblank_event_delivered(e->base.pid, e->pipe,
+e->event.sequence);
+}
+
 void drm_vblank_off(struct drm_device *dev, int crtc)
 {
struct drm_pending_vblank_event *e, *t;
@@ -950,14 +962,8 @@ void drm_vblank_off(struct drm_device *dev, int crtc)
  wanted %d, current %d\n",
  e->event.sequence, seq);

-   e->event.sequence = seq;
-   e->event.tv_sec = now.tv_sec;
-   e->event.tv_usec = now.tv_usec;
drm_vblank_put(dev, e->pipe);
-   list_move_tail(&e->base.link, &e->base.file_priv->event_list);
-   wake_up_interruptible(&e->base.file_priv->event_wait);
-   trace_drm_vblank_event_delivered(e->base.pid, e->pipe,
-e->event.sequence);
+   drm_emit_vblank_event(e, seq, &now);
}

WARN_ON(atomic_read(&dev->vblank_refcount[crtc]) != 0);
@@ -1103,18 +1109,11 @@ static int drm_queue_vblank_event(struct drm_device 
*dev, int pipe,
  vblwait->request.sequence);

e->event.sequence = vblwait->request.sequence;
+   list_add_tail(&e->base.link, &dev->vblank_event_list);
if ((seq - vblwait->request.sequence) <= (1 << 23)) {
-   e->event.sequence = seq;
-   e->event.tv_sec = now.tv_sec;
-   e->event.tv_usec = now.tv_usec;
drm_vblank_put(dev, pipe);
-   list_add_tail(&e->base.link, &e->base.file_priv->event_list);
-   wake_up_interruptible(&e->base.file_priv->event_wait);
-   vblwait->reply.sequence = seq;
-   trace_drm_vblank_event_delivered(current->pid, pipe,
-vblwait->request.sequence);
+   drm_emit_vblank_event(e, seq, &now);
} else {
-   list_add_tail(&e->base.link, &dev->vblank_event_list);
vblwait->reply.sequence = vblwait->request.sequence;
}

@@ -1248,14 +1247,8 @@ void drm_handle_vblank_events(struct drm_device *dev, 
int crtc)
DRM_DEBUG("vblank event on %d, current %d\n",
  e->event.sequence, seq);

-   e->event.sequence = seq;
-   e->event.tv_sec = now.tv_sec;
-   e->event.tv_usec = now.tv_usec;
drm_vblank_put(dev, e->pipe);
-   list_move_tail(&e->base.link, &e->base.file_priv->event_list);
-   wake_up_interruptible(&e->base.file_priv->event_wait);
-   trace_drm_vblank_event_delivered(e->base.pid, e->pipe,
-e->event.sequence);
+   drm_emit_vblank_event(e, seq, &now);
}

spin_unlock_irqrestore(&dev->event_lock, flags);
-- 
1.7.4.1

[PATCH] drm: Factor-out drm_emit_vblank_event code. (v2)

[christopher.halse.rog...@canonical.com]

From: Christopher James Halse Rogers 

v2: Also pull out the drm_vblank_put call.
Signed-off-by: Christopher James Halse Rogers 
---
 drivers/gpu/drm/drm_irq.c |   44 ++--
 1 files changed, 18 insertions(+), 26 deletions(-)

diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index 982ca8c..da56685 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -931,6 +931,20 @@ void drm_vblank_put(struct drm_device *dev, int crtc)
 }
 EXPORT_SYMBOL(drm_vblank_put);

+static void drm_emit_vblank_event (struct drm_device *dev,
+  struct drm_pending_vblank_event *e,
+  unsigned int seq, struct timeval *now)
+{
+   e->event.sequence = seq;
+   e->event.tv_sec = now->tv_sec;
+   e->event.tv_usec = now->tv_usec;
+   drm_vblank_put(dev, e->pipe);
+   list_move_tail(&e->base.link, &e->base.file_priv->event_list);
+   wake_up_interruptible(&e->base.file_priv->event_wait);
+   trace_drm_vblank_event_delivered(e->base.pid, e->pipe,
+e->event.sequence);
+}
+
 void drm_vblank_off(struct drm_device *dev, int crtc)
 {
struct drm_pending_vblank_event *e, *t;
@@ -951,14 +965,7 @@ void drm_vblank_off(struct drm_device *dev, int crtc)
  wanted %d, current %d\n",
  e->event.sequence, seq);

-   e->event.sequence = seq;
-   e->event.tv_sec = now.tv_sec;
-   e->event.tv_usec = now.tv_usec;
-   drm_vblank_put(dev, e->pipe);
-   list_move_tail(&e->base.link, &e->base.file_priv->event_list);
-   wake_up_interruptible(&e->base.file_priv->event_wait);
-   trace_drm_vblank_event_delivered(e->base.pid, e->pipe,
-e->event.sequence);
+   drm_emit_vblank_event(dev, e, seq, &now);
}

WARN_ON(atomic_read(&dev->vblank_refcount[crtc]) != 0);
@@ -1104,18 +,10 @@ static int drm_queue_vblank_event(struct drm_device 
*dev, int pipe,
  vblwait->request.sequence);

e->event.sequence = vblwait->request.sequence;
+   list_add_tail(&e->base.link, &dev->vblank_event_list);
if ((seq - vblwait->request.sequence) <= (1 << 23)) {
-   e->event.sequence = seq;
-   e->event.tv_sec = now.tv_sec;
-   e->event.tv_usec = now.tv_usec;
-   drm_vblank_put(dev, pipe);
-   list_add_tail(&e->base.link, &e->base.file_priv->event_list);
-   wake_up_interruptible(&e->base.file_priv->event_wait);
-   vblwait->reply.sequence = seq;
-   trace_drm_vblank_event_delivered(current->pid, pipe,
-vblwait->request.sequence);
+   drm_emit_vblank_event(dev, e, seq, &now);
} else {
-   list_add_tail(&e->base.link, &dev->vblank_event_list);
vblwait->reply.sequence = vblwait->request.sequence;
}

@@ -1249,14 +1248,7 @@ void drm_handle_vblank_events(struct drm_device *dev, 
int crtc)
DRM_DEBUG("vblank event on %d, current %d\n",
  e->event.sequence, seq);

-   e->event.sequence = seq;
-   e->event.tv_sec = now.tv_sec;
-   e->event.tv_usec = now.tv_usec;
-   drm_vblank_put(dev, e->pipe);
-   list_move_tail(&e->base.link, &e->base.file_priv->event_list);
-   wake_up_interruptible(&e->base.file_priv->event_wait);
-   trace_drm_vblank_event_delivered(e->base.pid, e->pipe,
-e->event.sequence);
+   drm_emit_vblank_event(dev, e, seq, &now);
}

spin_unlock_irqrestore(&dev->event_lock, flags);
-- 
1.7.4.1

[PATCH] drm: Factor-out drm_emit_vblank_event code. (v3)

[christopher.halse.rog...@canonical.com]

From: Christopher James Halse Rogers 

v2: Also pull out the drm_vblank_put call.
v3: Always set the reply.sequence value properly.

Signed-off-by: Christopher James Halse Rogers 
---
 drivers/gpu/drm/drm_irq.c |   43 ++-
 1 files changed, 18 insertions(+), 25 deletions(-)

diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index 982ca8c..c05fe41 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -931,6 +931,20 @@ void drm_vblank_put(struct drm_device *dev, int crtc)
 }
 EXPORT_SYMBOL(drm_vblank_put);

+static void drm_emit_vblank_event (struct drm_device *dev,
+  struct drm_pending_vblank_event *e,
+  unsigned int seq, struct timeval *now)
+{
+   e->event.sequence = seq;
+   e->event.tv_sec = now->tv_sec;
+   e->event.tv_usec = now->tv_usec;
+   drm_vblank_put(dev, e->pipe);
+   list_move_tail(&e->base.link, &e->base.file_priv->event_list);
+   wake_up_interruptible(&e->base.file_priv->event_wait);
+   trace_drm_vblank_event_delivered(e->base.pid, e->pipe,
+e->event.sequence);
+}
+
 void drm_vblank_off(struct drm_device *dev, int crtc)
 {
struct drm_pending_vblank_event *e, *t;
@@ -951,14 +965,7 @@ void drm_vblank_off(struct drm_device *dev, int crtc)
  wanted %d, current %d\n",
  e->event.sequence, seq);

-   e->event.sequence = seq;
-   e->event.tv_sec = now.tv_sec;
-   e->event.tv_usec = now.tv_usec;
-   drm_vblank_put(dev, e->pipe);
-   list_move_tail(&e->base.link, &e->base.file_priv->event_list);
-   wake_up_interruptible(&e->base.file_priv->event_wait);
-   trace_drm_vblank_event_delivered(e->base.pid, e->pipe,
-e->event.sequence);
+   drm_emit_vblank_event(dev, e, seq, &now);
}

WARN_ON(atomic_read(&dev->vblank_refcount[crtc]) != 0);
@@ -1104,18 +,11 @@ static int drm_queue_vblank_event(struct drm_device 
*dev, int pipe,
  vblwait->request.sequence);

e->event.sequence = vblwait->request.sequence;
+   list_add_tail(&e->base.link, &dev->vblank_event_list);
if ((seq - vblwait->request.sequence) <= (1 << 23)) {
-   e->event.sequence = seq;
-   e->event.tv_sec = now.tv_sec;
-   e->event.tv_usec = now.tv_usec;
-   drm_vblank_put(dev, pipe);
-   list_add_tail(&e->base.link, &e->base.file_priv->event_list);
-   wake_up_interruptible(&e->base.file_priv->event_wait);
+   drm_emit_vblank_event(dev, e, seq, &now);
vblwait->reply.sequence = seq;
-   trace_drm_vblank_event_delivered(current->pid, pipe,
-vblwait->request.sequence);
} else {
-   list_add_tail(&e->base.link, &dev->vblank_event_list);
vblwait->reply.sequence = vblwait->request.sequence;
}

@@ -1249,14 +1249,7 @@ void drm_handle_vblank_events(struct drm_device *dev, 
int crtc)
DRM_DEBUG("vblank event on %d, current %d\n",
  e->event.sequence, seq);

-   e->event.sequence = seq;
-   e->event.tv_sec = now.tv_sec;
-   e->event.tv_usec = now.tv_usec;
-   drm_vblank_put(dev, e->pipe);
-   list_move_tail(&e->base.link, &e->base.file_priv->event_list);
-   wake_up_interruptible(&e->base.file_priv->event_wait);
-   trace_drm_vblank_event_delivered(e->base.pid, e->pipe,
-e->event.sequence);
+   drm_emit_vblank_event(dev, e, seq, &now);
}

spin_unlock_irqrestore(&dev->event_lock, flags);
-- 
1.7.4.1