[RFC 17/29] dma-buf/fence: store last signaled value on fence timeline

Gustavo Padovan gustavo at padovan.org
Fri Jan 15 06:55:27 PST 2016


From: Gustavo Padovan <gustavo.padovan at collabora.co.uk>

Now fence timeline is aware of the last signaled fence, as it
receives the increment to the current value in fence_timeline_signal().

That allow us to create a fence_default_signaled() using timeline->value
and fence->seqno in the comparison.

Signed-off-by: Gustavo Padovan <gustavo.padovan at collabora.co.uk>
---
 drivers/dma-buf/fence.c           | 21 +++++++++++++++++++--
 drivers/staging/android/sw_sync.c | 16 ++--------------
 drivers/staging/android/sync.c    | 17 +++--------------
 drivers/staging/android/sync.h    |  3 ++-
 include/linux/fence.h             | 12 +++---------
 5 files changed, 29 insertions(+), 40 deletions(-)

diff --git a/drivers/dma-buf/fence.c b/drivers/dma-buf/fence.c
index f77d6a9..786c987 100644
--- a/drivers/dma-buf/fence.c
+++ b/drivers/dma-buf/fence.c
@@ -149,7 +149,7 @@ void fence_timeline_destroy(struct fence_timeline *timeline)
 	/*
 	 * signal any children that their parent is going away.
 	 */
-	fence_timeline_signal(timeline);
+	fence_timeline_signal(timeline, 0);
 	fence_timeline_put(timeline);
 }
 EXPORT_SYMBOL(fence_timeline_destroy);
@@ -157,11 +157,12 @@ EXPORT_SYMBOL(fence_timeline_destroy);
 /**
  * fence_timeline_signal - signal fences on a fence_timeline
  * @timeline	[in]	the fence_timeline to signal fences
+ * @inc		[in[	num to increment on timeline->value
  *
  * This function signal fences on a given timeline and remove
  * those from the active_list.
  */
-void fence_timeline_signal(struct fence_timeline *timeline)
+void fence_timeline_signal(struct fence_timeline *timeline, unsigned int inc)
 {
 	unsigned long flags;
 	LIST_HEAD(signaled_pts);
@@ -169,6 +170,8 @@ void fence_timeline_signal(struct fence_timeline *timeline)
 
 	spin_lock_irqsave(&timeline->lock, flags);
 
+	timeline->value += inc;
+
 	list_for_each_entry_safe(fence, next, &timeline->active_list_head,
 				 active_list) {
 		if (fence_is_signaled_locked(fence))
@@ -470,6 +473,20 @@ const char *fence_default_get_timeline_name(struct fence *fence)
 EXPORT_SYMBOL(fence_default_get_timeline_name);
 
 /**
+ * fence_default_signaled - default .signaled fence ops
+ * @fence:	[in]	the fence to check if signaled or not
+ *
+ * This functions checks if a fence was signaled or not.
+ */
+bool fence_default_signaled(struct fence *fence)
+{
+	struct fence_timeline *timeline = fence_parent(fence);
+
+	return (fence->seqno > timeline->value) ? false : true;
+}
+EXPORT_SYMBOL(fence_default_signaled);
+
+/**
  * fence_default_enable_signaling - default op for .enable_signaling
  * @fence:	[in]	the fence to enable signaling
  *
diff --git a/drivers/staging/android/sw_sync.c b/drivers/staging/android/sw_sync.c
index 9720267..bed6801 100644
--- a/drivers/staging/android/sw_sync.c
+++ b/drivers/staging/android/sw_sync.c
@@ -30,7 +30,7 @@ struct fence *sw_sync_pt_create(struct sw_sync_timeline *obj, u32 value)
 	struct sw_sync_pt *pt;
 
 	pt = (struct sw_sync_pt *)
-		sync_pt_create(&obj->obj, sizeof(struct sw_sync_pt));
+		sync_pt_create(&obj->obj, sizeof(struct sw_sync_pt), value);
 
 	pt->value = value;
 
@@ -38,15 +38,6 @@ struct fence *sw_sync_pt_create(struct sw_sync_timeline *obj, u32 value)
 }
 EXPORT_SYMBOL(sw_sync_pt_create);
 
-static int sw_sync_fence_has_signaled(struct fence *fence)
-{
-	struct sw_sync_pt *pt = (struct sw_sync_pt *)fence;
-	struct sw_sync_timeline *obj =
-		(struct sw_sync_timeline *)fence_parent(fence);
-
-	return (pt->value > obj->value) ? 0 : 1;
-}
-
 static int sw_sync_fill_driver_data(struct fence *fence,
 				    void *data, int size)
 {
@@ -77,7 +68,6 @@ static void sw_sync_fence_value_str(struct fence *fence,
 }
 
 static struct fence_timeline_ops sw_sync_timeline_ops = {
-	.has_signaled = sw_sync_fence_has_signaled,
 	.fill_driver_data = sw_sync_fill_driver_data,
 	.timeline_value_str = sw_sync_timeline_value_str,
 	.fence_value_str = sw_sync_fence_value_str,
@@ -96,8 +86,6 @@ EXPORT_SYMBOL(sw_sync_timeline_create);
 
 void sw_sync_timeline_inc(struct sw_sync_timeline *obj, u32 inc)
 {
-	obj->value += inc;
-
-	fence_timeline_signal(&obj->obj);
+	fence_timeline_signal(&obj->obj, inc);
 }
 EXPORT_SYMBOL(sw_sync_timeline_inc);
diff --git a/drivers/staging/android/sync.c b/drivers/staging/android/sync.c
index f8b3c6b..8216635 100644
--- a/drivers/staging/android/sync.c
+++ b/drivers/staging/android/sync.c
@@ -34,7 +34,7 @@
 static const struct fence_ops sync_fence_ops;
 static const struct file_operations sync_fence_fops;
 
-struct fence *sync_pt_create(struct fence_timeline *obj, int size)
+struct fence *sync_pt_create(struct fence_timeline *obj, int size, u32 value)
 {
 	unsigned long flags;
 	struct fence *fence;
@@ -49,7 +49,7 @@ struct fence *sync_pt_create(struct fence_timeline *obj, int size)
 	spin_lock_irqsave(&obj->lock, flags);
 	fence_timeline_get(obj);
 	fence_init(fence, &sync_fence_ops, &obj->lock,
-		   obj->context, ++obj->value);
+		   obj->context, value);
 	list_add_tail(&fence->child_list, &obj->child_list_head);
 	INIT_LIST_HEAD(&fence->active_list);
 	spin_unlock_irqrestore(&obj->lock, flags);
@@ -321,17 +321,6 @@ int sync_fence_wait(struct sync_fence *sync_fence, long timeout)
 }
 EXPORT_SYMBOL(sync_fence_wait);
 
-static bool sync_fence_signaled(struct fence *fence)
-{
-	struct fence_timeline *parent = fence_parent(fence);
-	int ret;
-
-	ret = parent->ops->has_signaled(fence);
-	if (ret < 0)
-		fence->status = ret;
-	return ret;
-}
-
 static int sync_fence_fill_driver_data(struct fence *fence,
 					  void *data, int size)
 {
@@ -372,7 +361,7 @@ static const struct fence_ops sync_fence_ops = {
 	.get_driver_name = fence_default_get_driver_name,
 	.get_timeline_name = fence_default_get_timeline_name,
 	.enable_signaling = fence_default_enable_signaling,
-	.signaled = sync_fence_signaled,
+	.signaled = fence_default_signaled,
 	.wait = fence_default_wait,
 	.release = fence_default_release,
 	.fill_driver_data = sync_fence_fill_driver_data,
diff --git a/drivers/staging/android/sync.h b/drivers/staging/android/sync.h
index e011111..569873f 100644
--- a/drivers/staging/android/sync.h
+++ b/drivers/staging/android/sync.h
@@ -82,7 +82,8 @@ static inline void sync_fence_waiter_init(struct sync_fence_waiter *waiter,
  * API for fence_timeline implementers
  */
 
-struct fence *sync_pt_create(struct fence_timeline *parent, int size);
+struct fence *sync_pt_create(struct fence_timeline *parent, int size,
+			     u32 value);
 
 /**
  * sync_fence_create() - creates a sync fence
diff --git a/include/linux/fence.h b/include/linux/fence.h
index e8f9f12..e71545e 100644
--- a/include/linux/fence.h
+++ b/include/linux/fence.h
@@ -36,10 +36,6 @@ struct fence_ops;
 struct fence_cb;
 /**
  * struct fence_timeline_ops - fence context implementation ops
- * @has_signaled:	returns:
- *			  1 if pt has signaled
- *			  0 if pt has not signaled
- *			 <0 on error
  * @fill_driver_data:	write implementation specific driver data to data.
  *			  should return an error if there is not enough room
  *			  as specified by size.  This information is returned
@@ -48,9 +44,6 @@ struct fence_cb;
  * @pt_value_str:	fill str with the value of the sync_pt
  */
 struct fence_timeline_ops {
-	/* required */
-	int (*has_signaled)(struct fence *fence);
-
 	/* optional */
 	int (*fill_driver_data)(struct fence *fence, void *data, int size);
 
@@ -80,7 +73,7 @@ struct fence_timeline {
 	char			drv_name[32];
 	const struct fence_timeline_ops *ops;
 	bool			destroyed;
-	int			value;
+	unsigned int		value;
 	int			context;
 	struct list_head	child_list_head;
 	struct list_head	active_list_head;
@@ -97,7 +90,7 @@ struct fence_timeline *fence_timeline_create(unsigned num,
 void fence_timeline_get(struct fence_timeline *timeline);
 void fence_timeline_put(struct fence_timeline *timeline);
 void fence_timeline_destroy(struct fence_timeline *timeline);
-void fence_timeline_signal(struct fence_timeline *timeline);
+void fence_timeline_signal(struct fence_timeline *timeline, unsigned int inc);
 
 /**
  * struct fence - software synchronization primitive
@@ -296,6 +289,7 @@ int fence_signal(struct fence *fence);
 int fence_signal_locked(struct fence *fence);
 const char *fence_default_get_driver_name(struct fence *fence);
 const char *fence_default_get_timeline_name(struct fence *fence);
+bool fence_default_signaled(struct fence *fence);
 bool fence_default_enable_signaling(struct fence *fence);
 signed long fence_default_wait(struct fence *fence, bool intr, signed long timeout);
 void fence_default_release(struct fence *fence);
-- 
2.5.0



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