android: convert sync to fence api, v6

Just to show it's easy.

Android syncpoints can be mapped to a timeline. This removes the need
to maintain a separate api for synchronization. I've left the android
trace events in place, but the core fence events should already be
sufficient for debugging.

v2:
- Call fence_remove_callback in sync_fence_free if not all fences have fired.
v3:
- Merge Colin Cross' bugfixes, and the android fence merge optimization.
v4:
- Merge with the upstream fixes.
v5:
- Fix small style issues pointed out by Thomas Hellstrom.
v6:
- Fix for updates to fence api.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Acked-by: John Stultz <john.stultz@linaro.org>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/android/Kconfig

@@ -88,6 +88,7 @@ config SYNC
 	bool "Synchronization framework"
 	default n
 	select ANON_INODES
+	select DMA_SHARED_BUFFER
 	---help---
 	  This option enables the framework for synchronization between multiple
 	  drivers.  Sync implementations can take advantage of hardware

drivers/staging/android/Makefile

@@ -9,5 +9,5 @@ obj-$(CONFIG_ANDROID_TIMED_OUTPUT)	+= timed_output.o
 obj-$(CONFIG_ANDROID_TIMED_GPIO)	+= timed_gpio.o
 obj-$(CONFIG_ANDROID_LOW_MEMORY_KILLER)	+= lowmemorykiller.o
 obj-$(CONFIG_ANDROID_INTF_ALARM_DEV)	+= alarm-dev.o
-obj-$(CONFIG_SYNC)			+= sync.o
+obj-$(CONFIG_SYNC)			+= sync.o sync_debug.o
 obj-$(CONFIG_SW_SYNC)			+= sw_sync.o

drivers/staging/android/sw_sync.c

@@ -50,7 +50,7 @@ static struct sync_pt *sw_sync_pt_dup(struct sync_pt *sync_pt)
 {
 	struct sw_sync_pt *pt = (struct sw_sync_pt *) sync_pt;
 	struct sw_sync_timeline *obj =
-		(struct sw_sync_timeline *)sync_pt->parent;
+		(struct sw_sync_timeline *)sync_pt_parent(sync_pt);
 
 	return (struct sync_pt *) sw_sync_pt_create(obj, pt->value);
 }
@@ -59,7 +59,7 @@ static int sw_sync_pt_has_signaled(struct sync_pt *sync_pt)
 {
 	struct sw_sync_pt *pt = (struct sw_sync_pt *)sync_pt;
 	struct sw_sync_timeline *obj =
-		(struct sw_sync_timeline *)sync_pt->parent;
+		(struct sw_sync_timeline *)sync_pt_parent(sync_pt);
 
 	return sw_sync_cmp(obj->value, pt->value) >= 0;
 }
@@ -97,7 +97,6 @@ static void sw_sync_pt_value_str(struct sync_pt *sync_pt,
 				       char *str, int size)
 {
 	struct sw_sync_pt *pt = (struct sw_sync_pt *)sync_pt;
-
 	snprintf(str, size, "%d", pt->value);
 }
 
@@ -157,7 +156,6 @@ static int sw_sync_open(struct inode *inode, struct file *file)
 static int sw_sync_release(struct inode *inode, struct file *file)
 {
 	struct sw_sync_timeline *obj = file->private_data;
-
 	sync_timeline_destroy(&obj->obj);
 	return 0;
 }

drivers/staging/android/sync.h

@@ -19,6 +19,7 @@
 #include <linux/list.h>
 #include <linux/spinlock.h>
 #include <linux/wait.h>
+#include <linux/fence.h>
 
 #include "uapi/sync.h"
 
@@ -40,8 +41,6 @@ struct sync_fence;
  *			 -1 if a will signal before b
  * @free_pt:		called before sync_pt is freed
  * @release_obj:	called before sync_timeline is freed
- * @print_obj:		deprecated
- * @print_pt:		deprecated
  * @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
@@ -67,13 +66,6 @@ struct sync_timeline_ops {
 	/* optional */
 	void (*release_obj)(struct sync_timeline *sync_timeline);
 
-	/* deprecated */
-	void (*print_obj)(struct seq_file *s,
-			  struct sync_timeline *sync_timeline);
-
-	/* deprecated */
-	void (*print_pt)(struct seq_file *s, struct sync_pt *sync_pt);
-
 	/* optional */
 	int (*fill_driver_data)(struct sync_pt *syncpt, void *data, int size);
 
@@ -104,19 +96,21 @@ struct sync_timeline {
 
 	/* protected by child_list_lock */
 	bool			destroyed;
+	int			context, value;
 
 	struct list_head	child_list_head;
 	spinlock_t		child_list_lock;
 
 	struct list_head	active_list_head;
-	spinlock_t		active_list_lock;
 
+#ifdef CONFIG_DEBUG_FS
 	struct list_head	sync_timeline_list;
+#endif
 };
 
 /**
  * struct sync_pt - sync point
- * @parent:		sync_timeline to which this sync_pt belongs
+ * @fence:		base fence class
  * @child_list:		membership in sync_timeline.child_list_head
  * @active_list:	membership in sync_timeline.active_list_head
  * @signaled_list:	membership in temporary signaled_list on stack
@@ -127,19 +121,22 @@ struct sync_timeline {
  *			  signaled or error.
  */
 struct sync_pt {
-	struct sync_timeline		*parent;
+	struct fence base;
+
 	struct list_head	child_list;
-
 	struct list_head	active_list;
-	struct list_head	signaled_list;
+};
 
-	struct sync_fence	*fence;
-	struct list_head	pt_list;
+static inline struct sync_timeline *sync_pt_parent(struct sync_pt *pt)
+{
+	return container_of(pt->base.lock, struct sync_timeline,
+			    child_list_lock);
+}
 
-	/* protected by parent->active_list_lock */
-	int			status;
-
-	ktime_t			timestamp;
+struct sync_fence_cb {
+	struct fence_cb cb;
+	struct fence *sync_pt;
+	struct sync_fence *fence;
 };
 
 /**
@@ -149,9 +146,7 @@ struct sync_pt {
  * @name:		name of sync_fence.  Useful for debugging
  * @pt_list_head:	list of sync_pts in the fence.  immutable once fence
  *			  is created
- * @waiter_list_head:	list of asynchronous waiters on this fence
- * @waiter_list_lock:	lock protecting @waiter_list_head and @status
- * @status:		1: signaled, 0:active, <0: error
+ * @status:		0: signaled, >0:active, <0: error
  *
  * @wq:			wait queue for fence signaling
  * @sync_fence_list:	membership in global fence list
@@ -160,17 +155,15 @@ struct sync_fence {
 	struct file		*file;
 	struct kref		kref;
 	char			name[32];
-
-	/* this list is immutable once the fence is created */
-	struct list_head	pt_list_head;
-
-	struct list_head	waiter_list_head;
-	spinlock_t		waiter_list_lock; /* also protects status */
-	int			status;
+#ifdef CONFIG_DEBUG_FS
+	struct list_head	sync_fence_list;
+#endif
+	int num_fences;
 
 	wait_queue_head_t	wq;
+	atomic_t		status;
 
-	struct list_head	sync_fence_list;
+	struct sync_fence_cb	cbs[];
 };
 
 struct sync_fence_waiter;
@@ -184,14 +177,14 @@ typedef void (*sync_callback_t)(struct sync_fence *fence,
  * @callback_data:	pointer to pass to @callback
  */
 struct sync_fence_waiter {
-	struct list_head	waiter_list;
-
-	sync_callback_t		callback;
+	wait_queue_t work;
+	sync_callback_t callback;
 };
 
 static inline void sync_fence_waiter_init(struct sync_fence_waiter *waiter,
 					  sync_callback_t callback)
 {
+	INIT_LIST_HEAD(&waiter->work.task_list);
 	waiter->callback = callback;
 }
 
@@ -341,4 +334,22 @@ int sync_fence_cancel_async(struct sync_fence *fence,
  */
 int sync_fence_wait(struct sync_fence *fence, long timeout);
 
+#ifdef CONFIG_DEBUG_FS
+
+extern void sync_timeline_debug_add(struct sync_timeline *obj);
+extern void sync_timeline_debug_remove(struct sync_timeline *obj);
+extern void sync_fence_debug_add(struct sync_fence *fence);
+extern void sync_fence_debug_remove(struct sync_fence *fence);
+extern void sync_dump(void);
+
+#else
+# define sync_timeline_debug_add(obj)
+# define sync_timeline_debug_remove(obj)
+# define sync_fence_debug_add(fence)
+# define sync_fence_debug_remove(fence)
+# define sync_dump()
+#endif
+int sync_fence_wake_up_wq(wait_queue_t *curr, unsigned mode,
+				 int wake_flags, void *key);
+
 #endif /* _LINUX_SYNC_H */

drivers/staging/android/sync_debug.c

@@ -0,0 +1,247 @@
+/*
+ * drivers/base/sync.c
+ *
+ * Copyright (C) 2012 Google, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/debugfs.h>
+#include <linux/export.h>
+#include <linux/file.h>
+#include <linux/fs.h>
+#include <linux/kernel.h>
+#include <linux/poll.h>
+#include <linux/sched.h>
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/anon_inodes.h>
+#include "sync.h"
+
+#ifdef CONFIG_DEBUG_FS
+
+static LIST_HEAD(sync_timeline_list_head);
+static DEFINE_SPINLOCK(sync_timeline_list_lock);
+static LIST_HEAD(sync_fence_list_head);
+static DEFINE_SPINLOCK(sync_fence_list_lock);
+
+void sync_timeline_debug_add(struct sync_timeline *obj)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&sync_timeline_list_lock, flags);
+	list_add_tail(&obj->sync_timeline_list, &sync_timeline_list_head);
+	spin_unlock_irqrestore(&sync_timeline_list_lock, flags);
+}
+
+void sync_timeline_debug_remove(struct sync_timeline *obj)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&sync_timeline_list_lock, flags);
+	list_del(&obj->sync_timeline_list);
+	spin_unlock_irqrestore(&sync_timeline_list_lock, flags);
+}
+
+void sync_fence_debug_add(struct sync_fence *fence)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&sync_fence_list_lock, flags);
+	list_add_tail(&fence->sync_fence_list, &sync_fence_list_head);
+	spin_unlock_irqrestore(&sync_fence_list_lock, flags);
+}
+
+void sync_fence_debug_remove(struct sync_fence *fence)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&sync_fence_list_lock, flags);
+	list_del(&fence->sync_fence_list);
+	spin_unlock_irqrestore(&sync_fence_list_lock, flags);
+}
+
+static const char *sync_status_str(int status)
+{
+	if (status == 0)
+		return "signaled";
+	else if (status > 0)
+		return "active";
+	else
+		return "error";
+}
+
+static void sync_print_pt(struct seq_file *s, struct sync_pt *pt, bool fence)
+{
+	int status = 1;
+	struct sync_timeline *parent = sync_pt_parent(pt);
+
+	if (fence_is_signaled_locked(&pt->base))
+		status = pt->base.status;
+
+	seq_printf(s, "  %s%spt %s",
+		   fence ? parent->name : "",
+		   fence ? "_" : "",
+		   sync_status_str(status));
+
+	if (status <= 0) {
+		struct timeval tv = ktime_to_timeval(pt->base.timestamp);
+		seq_printf(s, "@%ld.%06ld", tv.tv_sec, tv.tv_usec);
+	}
+
+	if (parent->ops->timeline_value_str &&
+	    parent->ops->pt_value_str) {
+		char value[64];
+		parent->ops->pt_value_str(pt, value, sizeof(value));
+		seq_printf(s, ": %s", value);
+		if (fence) {
+			parent->ops->timeline_value_str(parent, value,
+						    sizeof(value));
+			seq_printf(s, " / %s", value);
+		}
+	}
+
+	seq_puts(s, "\n");
+}
+
+static void sync_print_obj(struct seq_file *s, struct sync_timeline *obj)
+{
+	struct list_head *pos;
+	unsigned long flags;
+
+	seq_printf(s, "%s %s", obj->name, obj->ops->driver_name);
+
+	if (obj->ops->timeline_value_str) {
+		char value[64];
+		obj->ops->timeline_value_str(obj, value, sizeof(value));
+		seq_printf(s, ": %s", value);
+	}
+
+	seq_puts(s, "\n");
+
+	spin_lock_irqsave(&obj->child_list_lock, flags);
+	list_for_each(pos, &obj->child_list_head) {
+		struct sync_pt *pt =
+			container_of(pos, struct sync_pt, child_list);
+		sync_print_pt(s, pt, false);
+	}
+	spin_unlock_irqrestore(&obj->child_list_lock, flags);
+}
+
+static void sync_print_fence(struct seq_file *s, struct sync_fence *fence)
+{
+	wait_queue_t *pos;
+	unsigned long flags;
+	int i;
+
+	seq_printf(s, "[%p] %s: %s\n", fence, fence->name,
+		   sync_status_str(atomic_read(&fence->status)));
+
+	for (i = 0; i < fence->num_fences; ++i) {
+		struct sync_pt *pt =
+			container_of(fence->cbs[i].sync_pt,
+				     struct sync_pt, base);
+
+		sync_print_pt(s, pt, true);
+	}
+
+	spin_lock_irqsave(&fence->wq.lock, flags);
+	list_for_each_entry(pos, &fence->wq.task_list, task_list) {
+		struct sync_fence_waiter *waiter;
+
+		if (pos->func != &sync_fence_wake_up_wq)
+			continue;
+
+		waiter = container_of(pos, struct sync_fence_waiter, work);
+
+		seq_printf(s, "waiter %pF\n", waiter->callback);
+	}
+	spin_unlock_irqrestore(&fence->wq.lock, flags);
+}
+
+static int sync_debugfs_show(struct seq_file *s, void *unused)
+{
+	unsigned long flags;
+	struct list_head *pos;
+
+	seq_puts(s, "objs:\n--------------\n");
+
+	spin_lock_irqsave(&sync_timeline_list_lock, flags);
+	list_for_each(pos, &sync_timeline_list_head) {
+		struct sync_timeline *obj =
+			container_of(pos, struct sync_timeline,
+				     sync_timeline_list);
+
+		sync_print_obj(s, obj);
+		seq_puts(s, "\n");
+	}
+	spin_unlock_irqrestore(&sync_timeline_list_lock, flags);
+
+	seq_puts(s, "fences:\n--------------\n");
+
+	spin_lock_irqsave(&sync_fence_list_lock, flags);
+	list_for_each(pos, &sync_fence_list_head) {
+		struct sync_fence *fence =
+			container_of(pos, struct sync_fence, sync_fence_list);
+
+		sync_print_fence(s, fence);
+		seq_puts(s, "\n");
+	}
+	spin_unlock_irqrestore(&sync_fence_list_lock, flags);
+	return 0;
+}
+
+static int sync_debugfs_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, sync_debugfs_show, inode->i_private);
+}
+
+static const struct file_operations sync_debugfs_fops = {
+	.open           = sync_debugfs_open,
+	.read           = seq_read,
+	.llseek         = seq_lseek,
+	.release        = single_release,
+};
+
+static __init int sync_debugfs_init(void)
+{
+	debugfs_create_file("sync", S_IRUGO, NULL, NULL, &sync_debugfs_fops);
+	return 0;
+}
+late_initcall(sync_debugfs_init);
+
+#define DUMP_CHUNK 256
+static char sync_dump_buf[64 * 1024];
+void sync_dump(void)
+{
+	struct seq_file s = {
+		.buf = sync_dump_buf,
+		.size = sizeof(sync_dump_buf) - 1,
+	};
+	int i;
+
+	sync_debugfs_show(&s, NULL);
+
+	for (i = 0; i < s.count; i += DUMP_CHUNK) {
+		if ((s.count - i) > DUMP_CHUNK) {
+			char c = s.buf[i + DUMP_CHUNK];
+			s.buf[i + DUMP_CHUNK] = 0;
+			pr_cont("%s", s.buf + i);
+			s.buf[i + DUMP_CHUNK] = c;
+		} else {
+			s.buf[s.count] = 0;
+			pr_cont("%s", s.buf + i);
+		}
+	}
+}
+
+#endif

drivers/staging/android/trace/sync.h

@@ -45,7 +45,7 @@ TRACE_EVENT(sync_wait,
 
 	TP_fast_assign(
 			__assign_str(name, fence->name);
-			__entry->status = fence->status;
+			__entry->status = atomic_read(&fence->status);
 			__entry->begin = begin;
 	),
 
@@ -54,19 +54,19 @@ TRACE_EVENT(sync_wait,
 );
 
 TRACE_EVENT(sync_pt,
-	TP_PROTO(struct sync_pt *pt),
+	TP_PROTO(struct fence *pt),
 
 	TP_ARGS(pt),
 
 	TP_STRUCT__entry(
-		__string(timeline, pt->parent->name)
+		__string(timeline, pt->ops->get_timeline_name(pt))
 		__array(char, value, 32)
 	),
 
 	TP_fast_assign(
-		__assign_str(timeline, pt->parent->name);
-		if (pt->parent->ops->pt_value_str) {
-			pt->parent->ops->pt_value_str(pt, __entry->value,
+		__assign_str(timeline, pt->ops->get_timeline_name(pt));
+		if (pt->ops->fence_value_str) {
+			pt->ops->fence_value_str(pt, __entry->value,
 							sizeof(__entry->value));
 		} else {
 			__entry->value[0] = '\0';