[PATCH v2 0/6] de-stage SW_SYNC validation frawework

[PATCH v2 0/6] de-stage SW_SYNC validation frawework

[Gustavo Padovan]

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

Hi Greg,

This is the last step in the Sync Framwork de-stage task. It de-stage
the SW_SYNC validation framework and the sync_debug info debugfs file.

The first 2 patches are clean up and improvements and the rest is preparation
to de-stage and then finally the actual de-stage.

v2: 
 - add documentation about the SW_SYNC ioctl API (comments from Pavel Machek)
 - remove for now patch to add sync_pt name to debugfs

Please review,

Gustavo

---
Gustavo Padovan (6):
  staging/android: remove doc from sw_sync
  staging/android: do not let userspace trigger WARN_ON
  staging/android: move trace/sync.h to sync_trace.h
  staging/android: prepare sw_sync files for de-staging
  staging/android: add Doc for SW_SYNC ioctl interface
  dma-buf/sw_sync: de-stage SW_SYNC

 drivers/dma-buf/Kconfig              |  13 ++
 drivers/dma-buf/Makefile             |   1 +
 drivers/dma-buf/sw_sync.c            | 349 +++++++++++++++++++++++++++++++++++
 drivers/dma-buf/sync_debug.c         | 230 +++++++++++++++++++++++
 drivers/dma-buf/sync_debug.h         |  69 +++++++
 drivers/dma-buf/sync_trace.h         |  32 ++++
 drivers/staging/android/Kconfig      |  13 --
 drivers/staging/android/Makefile     |   1 -
 drivers/staging/android/sw_sync.c    | 344 ----------------------------------
 drivers/staging/android/sync_debug.c | 230 -----------------------
 drivers/staging/android/sync_debug.h |  84 ---------
 drivers/staging/android/trace/sync.h |  32 ----
 12 files changed, 694 insertions(+), 704 deletions(-)
 create mode 100644 drivers/dma-buf/sw_sync.c
 create mode 100644 drivers/dma-buf/sync_debug.c
 create mode 100644 drivers/dma-buf/sync_debug.h
 create mode 100644 drivers/dma-buf/sync_trace.h
 delete mode 100644 drivers/staging/android/sw_sync.c
 delete mode 100644 drivers/staging/android/sync_debug.c
 delete mode 100644 drivers/staging/android/sync_debug.h
 delete mode 100644 drivers/staging/android/trace/sync.h

-- 
2.5.5

[PATCH v2 1/6] staging/android: remove doc from sw_sync

[Gustavo Padovan]

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

SW_SYNC should never be used by other pieces of the kernel apart from
sync_debug as it is only a Sync File Validation Framework, so hide any
info to avoid confuse this with a standard kernel internal API.

Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
---
 drivers/staging/android/sw_sync.c    | 26 --------------------------
 drivers/staging/android/sync_debug.h | 15 ---------------
 2 files changed, 41 deletions(-)

diff --git a/drivers/staging/android/sw_sync.c b/drivers/staging/android/sw_sync.c
index 115c917..b4ae092 100644
--- a/drivers/staging/android/sw_sync.c
+++ b/drivers/staging/android/sw_sync.c
@@ -46,13 +46,6 @@ static inline struct sync_pt *fence_to_sync_pt(struct fence *fence)
 	return container_of(fence, struct sync_pt, base);
 }
 
-/**
- * sync_timeline_create() - creates a sync object
- * @name:	sync_timeline name
- *
- * Creates a new sync_timeline. Returns the sync_timeline object or NULL in
- * case of error.
- */
 struct sync_timeline *sync_timeline_create(const char *name)
 {
 	struct sync_timeline *obj;
@@ -94,14 +87,6 @@ static void sync_timeline_put(struct sync_timeline *obj)
 	kref_put(&obj->kref, sync_timeline_free);
 }
 
-/**
- * sync_timeline_signal() - signal a status change on a sync_timeline
- * @obj:	sync_timeline to signal
- * @inc:	num to increment on timeline->value
- *
- * A sync implementation should call this any time one of it's fences
- * has signaled or has an error condition.
- */
 static void sync_timeline_signal(struct sync_timeline *obj, unsigned int inc)
 {
 	unsigned long flags;
@@ -122,17 +107,6 @@ static void sync_timeline_signal(struct sync_timeline *obj, unsigned int inc)
 	spin_unlock_irqrestore(&obj->child_list_lock, flags);
 }
 
-/**
- * sync_pt_create() - creates a sync pt
- * @parent:	fence's parent sync_timeline
- * @size:	size to allocate for this pt
- * @inc:	value of the fence
- *
- * Creates a new sync_pt as a child of @parent.  @size bytes will be
- * allocated allowing for implementation specific data to be kept after
- * the generic sync_timeline struct. Returns the sync_pt object or
- * NULL in case of error.
- */
 static struct sync_pt *sync_pt_create(struct sync_timeline *obj, int size,
 			     unsigned int value)
 {
diff --git a/drivers/staging/android/sync_debug.h b/drivers/staging/android/sync_debug.h
index fab6639..5b82cf8 100644
--- a/drivers/staging/android/sync_debug.h
+++ b/drivers/staging/android/sync_debug.h
@@ -20,15 +20,6 @@
 #include <linux/sync_file.h>
 #include <uapi/linux/sync_file.h>
 
-/**
- * struct sync_timeline - sync object
- * @kref:		reference count on fence.
- * @name:		name of the sync_timeline. Useful for debugging
- * @child_list_head:	list of children sync_pts for this sync_timeline
- * @child_list_lock:	lock protecting @child_list_head and fence.status
- * @active_list_head:	list of active (unsignaled/errored) sync_pts
- * @sync_timeline_list:	membership in global sync_timeline_list
- */
 struct sync_timeline {
 	struct kref		kref;
 	char			name[32];
@@ -51,12 +42,6 @@ static inline struct sync_timeline *fence_parent(struct fence *fence)
 			    child_list_lock);
 }
 
-/**
- * struct sync_pt - sync_pt object
- * @base: base fence object
- * @child_list: sync timeline child's list
- * @active_list: sync timeline active child's list
- */
 struct sync_pt {
 	struct fence base;
 	struct list_head child_list;
-- 
2.5.5

[PATCH v2 2/6] staging/android: do not let userspace trigger WARN_ON

[Gustavo Padovan]

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

Closing the timeline without waiting all fences to signal is not
a critical failure, it is just bad usage from userspace so avoid
calling WARN_ON in this case.

Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
---
 drivers/staging/android/sw_sync.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/staging/android/sw_sync.c b/drivers/staging/android/sw_sync.c
index b4ae092..ad0bb1a 100644
--- a/drivers/staging/android/sw_sync.c
+++ b/drivers/staging/android/sw_sync.c
@@ -150,7 +150,7 @@ static void timeline_fence_release(struct fence *fence)
 
 	spin_lock_irqsave(fence->lock, flags);
 	list_del(&pt->child_list);
-	if (WARN_ON_ONCE(!list_empty(&pt->active_list)))
+	if (!list_empty(&pt->active_list))
 		list_del(&pt->active_list);
 	spin_unlock_irqrestore(fence->lock, flags);
 
-- 
2.5.5

[PATCH v2 3/6] staging/android: move trace/sync.h to sync_trace.h

[Gustavo Padovan]

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

The common behaviour for trace headers is to have them in the same folder
they are used, instead of creating a special trace/ directory.

Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
---
 drivers/staging/android/sw_sync.c    |  2 +-
 drivers/staging/android/sync_trace.h | 32 ++++++++++++++++++++++++++++++++
 drivers/staging/android/trace/sync.h | 32 --------------------------------
 3 files changed, 33 insertions(+), 33 deletions(-)
 create mode 100644 drivers/staging/android/sync_trace.h
 delete mode 100644 drivers/staging/android/trace/sync.h

diff --git a/drivers/staging/android/sw_sync.c b/drivers/staging/android/sw_sync.c
index ad0bb1a..745597b 100644
--- a/drivers/staging/android/sw_sync.c
+++ b/drivers/staging/android/sw_sync.c
@@ -23,7 +23,7 @@
 #include "sync_debug.h"
 
 #define CREATE_TRACE_POINTS
-#include "trace/sync.h"
+#include "sync_trace.h"
 
 struct sw_sync_create_fence_data {
 	__u32	value;
diff --git a/drivers/staging/android/sync_trace.h b/drivers/staging/android/sync_trace.h
new file mode 100644
index 0000000..ea485f7
--- /dev/null
+++ b/drivers/staging/android/sync_trace.h
@@ -0,0 +1,32 @@
+#undef TRACE_SYSTEM
+#define TRACE_INCLUDE_PATH ../../drivers/staging/android
+#define TRACE_SYSTEM sync_trace
+
+#if !defined(_TRACE_SYNC_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_SYNC_H
+
+#include "sync_debug.h"
+#include <linux/tracepoint.h>
+
+TRACE_EVENT(sync_timeline,
+	TP_PROTO(struct sync_timeline *timeline),
+
+	TP_ARGS(timeline),
+
+	TP_STRUCT__entry(
+			__string(name, timeline->name)
+			__field(u32, value)
+	),
+
+	TP_fast_assign(
+			__assign_str(name, timeline->name);
+			__entry->value = timeline->value;
+	),
+
+	TP_printk("name=%s value=%d", __get_str(name), __entry->value)
+);
+
+#endif /* if !defined(_TRACE_SYNC_H) || defined(TRACE_HEADER_MULTI_READ) */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
diff --git a/drivers/staging/android/trace/sync.h b/drivers/staging/android/trace/sync.h
deleted file mode 100644
index 6b5ce96..0000000
--- a/drivers/staging/android/trace/sync.h
+++ /dev/null
@@ -1,32 +0,0 @@
-#undef TRACE_SYSTEM
-#define TRACE_INCLUDE_PATH ../../drivers/staging/android/trace
-#define TRACE_SYSTEM sync
-
-#if !defined(_TRACE_SYNC_H) || defined(TRACE_HEADER_MULTI_READ)
-#define _TRACE_SYNC_H
-
-#include "../sync_debug.h"
-#include <linux/tracepoint.h>
-
-TRACE_EVENT(sync_timeline,
-	TP_PROTO(struct sync_timeline *timeline),
-
-	TP_ARGS(timeline),
-
-	TP_STRUCT__entry(
-			__string(name, timeline->name)
-			__field(u32, value)
-	),
-
-	TP_fast_assign(
-			__assign_str(name, timeline->name);
-			__entry->value = timeline->value;
-	),
-
-	TP_printk("name=%s value=%d", __get_str(name), __entry->value)
-);
-
-#endif /* if !defined(_TRACE_SYNC_H) || defined(TRACE_HEADER_MULTI_READ) */
-
-/* This part must be outside protection */
-#include <trace/define_trace.h>
-- 
2.5.5

[PATCH v2 4/6] staging/android: prepare sw_sync files for de-staging

[Gustavo Padovan]

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

remove file paths in the comments and add short description about each
file.

v2: remove file paths instead of just change them.

Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
---
 drivers/staging/android/sw_sync.c    | 2 +-
 drivers/staging/android/sync_debug.c | 2 +-
 drivers/staging/android/sync_debug.h | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/android/sw_sync.c b/drivers/staging/android/sw_sync.c
index 745597b..43491b6 100644
--- a/drivers/staging/android/sw_sync.c
+++ b/drivers/staging/android/sw_sync.c
@@ -1,5 +1,5 @@
 /*
- * drivers/dma-buf/sw_sync.c
+ * Sync File validation framework
  *
  * Copyright (C) 2012 Google, Inc.
  *
diff --git a/drivers/staging/android/sync_debug.c b/drivers/staging/android/sync_debug.c
index 4c5a855..fab9520 100644
--- a/drivers/staging/android/sync_debug.c
+++ b/drivers/staging/android/sync_debug.c
@@ -1,5 +1,5 @@
 /*
- * drivers/base/sync.c
+ * Sync File validation framework and debug information
  *
  * Copyright (C) 2012 Google, Inc.
  *
diff --git a/drivers/staging/android/sync_debug.h b/drivers/staging/android/sync_debug.h
index 5b82cf8..ee3c27b 100644
--- a/drivers/staging/android/sync_debug.h
+++ b/drivers/staging/android/sync_debug.h
@@ -1,5 +1,5 @@
 /*
- * include/linux/sync.h
+ * Sync File validation framework
  *
  * Copyright (C) 2012 Google, Inc.
  *
-- 
2.5.5

[PATCH v2 5/6] staging/android: add Doc for SW_SYNC ioctl interface

[Gustavo Padovan]

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

This interface is hidden from kernel headers and it is intended for use
only for testing. So testers would have to add the ioctl information
internally. This is to prevent misuse of this feature.

Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
---
 drivers/staging/android/sw_sync.c | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/drivers/staging/android/sw_sync.c b/drivers/staging/android/sw_sync.c
index 43491b6..2ac5608 100644
--- a/drivers/staging/android/sw_sync.c
+++ b/drivers/staging/android/sw_sync.c
@@ -25,6 +25,36 @@
 #define CREATE_TRACE_POINTS
 #include "sync_trace.h"
 
+/*
+ * SW SYNC validation framework
+ *
+ * A sync object driver that uses a 32bit counter to coordinate
+ * synchronization.  Useful when there is no hardware primitive backing
+ * the synchronization.
+ *
+ * To start the framework just open:
+ *
+ * <debugfs>/sync/sw_sync
+ *
+ * That will create a sync timeline, all fences created under this timeline
+ * file descriptor will belong to the this timeline.
+ *
+ * The 'sw_sync' file can be opened many times as to create different
+ * timelines.
+ *
+ * Fences can be created with SW_SYNC_IOC_CREATE_FENCE ioctl with struct
+ * sw_sync_ioctl_create_fence as parameter.
+ *
+ * To increment the timeline counter SW_SYNC_IOC_INC ioctl should be used
+ * with the increment as u32. This will update the last signaled value
+ * from the timeline and signal any fence that has seqno, smaller of equal
+ * it.
+ *
+ * struct sw_sync_ioctl_create_fence
+ * @value:	the seqno to initiate the fence with
+ * @name:	the name of the new sync point
+ * @fence:	return the fd of the new sync_file with the created fence
+ */
 struct sw_sync_create_fence_data {
 	__u32	value;
 	char	name[32];
@@ -35,6 +65,7 @@ struct sw_sync_create_fence_data {
 
 #define SW_SYNC_IOC_CREATE_FENCE	_IOWR(SW_SYNC_IOC_MAGIC, 0,\
 		struct sw_sync_create_fence_data)
+
 #define SW_SYNC_IOC_INC			_IOW(SW_SYNC_IOC_MAGIC, 1, __u32)
 
 static const struct fence_ops timeline_fence_ops;
-- 
2.5.5

[PATCH v2 6/6] dma-buf/sw_sync: de-stage SW_SYNC

[Gustavo Padovan]

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

SW_SYNC allows to run tests on the sync_file framework via debugfs on

<debugfs>/sync/sw_sync

Opening and closing the file triggers creation and release of a sync
timeline. To create fences on this timeline the SW_SYNC_IOC_CREATE_FENCE
ioctl should be used. To increment the timeline value use SW_SYNC_IOC_INC.

Also it exports Sync information on

<debugfs>/sync/info

Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
---
 drivers/dma-buf/Kconfig              |  13 ++
 drivers/dma-buf/Makefile             |   1 +
 drivers/dma-buf/sw_sync.c            | 349 +++++++++++++++++++++++++++++++++++
 drivers/dma-buf/sync_debug.c         | 230 +++++++++++++++++++++++
 drivers/dma-buf/sync_debug.h         |  69 +++++++
 drivers/dma-buf/sync_trace.h         |  32 ++++
 drivers/staging/android/Kconfig      |  13 --
 drivers/staging/android/Makefile     |   1 -
 drivers/staging/android/sw_sync.c    | 349 -----------------------------------
 drivers/staging/android/sync_debug.c | 230 -----------------------
 drivers/staging/android/sync_debug.h |  69 -------
 drivers/staging/android/sync_trace.h |  32 ----
 12 files changed, 694 insertions(+), 694 deletions(-)
 create mode 100644 drivers/dma-buf/sw_sync.c
 create mode 100644 drivers/dma-buf/sync_debug.c
 create mode 100644 drivers/dma-buf/sync_debug.h
 create mode 100644 drivers/dma-buf/sync_trace.h
 delete mode 100644 drivers/staging/android/sw_sync.c
 delete mode 100644 drivers/staging/android/sync_debug.c
 delete mode 100644 drivers/staging/android/sync_debug.h
 delete mode 100644 drivers/staging/android/sync_trace.h

diff --git a/drivers/dma-buf/Kconfig b/drivers/dma-buf/Kconfig
index 25bcfa0..2585821 100644
--- a/drivers/dma-buf/Kconfig
+++ b/drivers/dma-buf/Kconfig
@@ -17,4 +17,17 @@ config SYNC_FILE
 	  Files fds, to the DRM driver for example. More details at
 	  Documentation/sync_file.txt.
 
+config SW_SYNC
+	bool "Sync File Validation Framework"
+	default n
+	depends on SYNC_FILE
+	depends on DEBUG_FS
+	---help---
+	  A sync object driver that uses a 32bit counter to coordinate
+	  synchronization.  Useful when there is no hardware primitive backing
+	  the synchronization.
+
+	  WARNING: improper use of this can result in deadlocking kernel
+	  drivers from userspace. Intended for test and debug only.
+
 endmenu
diff --git a/drivers/dma-buf/Makefile b/drivers/dma-buf/Makefile
index f353db2..210a10b 100644
--- a/drivers/dma-buf/Makefile
+++ b/drivers/dma-buf/Makefile
@@ -1,2 +1,3 @@
 obj-y := dma-buf.o fence.o reservation.o seqno-fence.o fence-array.o
 obj-$(CONFIG_SYNC_FILE)		+= sync_file.o
+obj-$(CONFIG_SW_SYNC)		+= sw_sync.o sync_debug.o
diff --git a/drivers/dma-buf/sw_sync.c b/drivers/dma-buf/sw_sync.c
new file mode 100644
index 0000000..2ac5608
--- /dev/null
+++ b/drivers/dma-buf/sw_sync.c
@@ -0,0 +1,349 @@
+/*
+ * Sync File validation framework
+ *
+ * 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/file.h>
+#include <linux/fs.h>
+#include <linux/uaccess.h>
+#include <linux/slab.h>
+#include <linux/sync_file.h>
+
+#include "sync_debug.h"
+
+#define CREATE_TRACE_POINTS
+#include "sync_trace.h"
+
+/*
+ * SW SYNC validation framework
+ *
+ * A sync object driver that uses a 32bit counter to coordinate
+ * synchronization.  Useful when there is no hardware primitive backing
+ * the synchronization.
+ *
+ * To start the framework just open:
+ *
+ * <debugfs>/sync/sw_sync
+ *
+ * That will create a sync timeline, all fences created under this timeline
+ * file descriptor will belong to the this timeline.
+ *
+ * The 'sw_sync' file can be opened many times as to create different
+ * timelines.
+ *
+ * Fences can be created with SW_SYNC_IOC_CREATE_FENCE ioctl with struct
+ * sw_sync_ioctl_create_fence as parameter.
+ *
+ * To increment the timeline counter SW_SYNC_IOC_INC ioctl should be used
+ * with the increment as u32. This will update the last signaled value
+ * from the timeline and signal any fence that has seqno, smaller of equal
+ * it.
+ *
+ * struct sw_sync_ioctl_create_fence
+ * @value:	the seqno to initiate the fence with
+ * @name:	the name of the new sync point
+ * @fence:	return the fd of the new sync_file with the created fence
+ */
+struct sw_sync_create_fence_data {
+	__u32	value;
+	char	name[32];
+	__s32	fence; /* fd of new fence */
+};
+
+#define SW_SYNC_IOC_MAGIC	'W'
+
+#define SW_SYNC_IOC_CREATE_FENCE	_IOWR(SW_SYNC_IOC_MAGIC, 0,\
+		struct sw_sync_create_fence_data)
+
+#define SW_SYNC_IOC_INC			_IOW(SW_SYNC_IOC_MAGIC, 1, __u32)
+
+static const struct fence_ops timeline_fence_ops;
+
+static inline struct sync_pt *fence_to_sync_pt(struct fence *fence)
+{
+	if (fence->ops != &timeline_fence_ops)
+		return NULL;
+	return container_of(fence, struct sync_pt, base);
+}
+
+struct sync_timeline *sync_timeline_create(const char *name)
+{
+	struct sync_timeline *obj;
+
+	obj = kzalloc(sizeof(*obj), GFP_KERNEL);
+	if (!obj)
+		return NULL;
+
+	kref_init(&obj->kref);
+	obj->context = fence_context_alloc(1);
+	strlcpy(obj->name, name, sizeof(obj->name));
+
+	INIT_LIST_HEAD(&obj->child_list_head);
+	INIT_LIST_HEAD(&obj->active_list_head);
+	spin_lock_init(&obj->child_list_lock);
+
+	sync_timeline_debug_add(obj);
+
+	return obj;
+}
+
+static void sync_timeline_free(struct kref *kref)
+{
+	struct sync_timeline *obj =
+		container_of(kref, struct sync_timeline, kref);
+
+	sync_timeline_debug_remove(obj);
+
+	kfree(obj);
+}
+
+static void sync_timeline_get(struct sync_timeline *obj)
+{
+	kref_get(&obj->kref);
+}
+
+static void sync_timeline_put(struct sync_timeline *obj)
+{
+	kref_put(&obj->kref, sync_timeline_free);
+}
+
+static void sync_timeline_signal(struct sync_timeline *obj, unsigned int inc)
+{
+	unsigned long flags;
+	struct sync_pt *pt, *next;
+
+	trace_sync_timeline(obj);
+
+	spin_lock_irqsave(&obj->child_list_lock, flags);
+
+	obj->value += inc;
+
+	list_for_each_entry_safe(pt, next, &obj->active_list_head,
+				 active_list) {
+		if (fence_is_signaled_locked(&pt->base))
+			list_del_init(&pt->active_list);
+	}
+
+	spin_unlock_irqrestore(&obj->child_list_lock, flags);
+}
+
+static struct sync_pt *sync_pt_create(struct sync_timeline *obj, int size,
+			     unsigned int value)
+{
+	unsigned long flags;
+	struct sync_pt *pt;
+
+	if (size < sizeof(*pt))
+		return NULL;
+
+	pt = kzalloc(size, GFP_KERNEL);
+	if (!pt)
+		return NULL;
+
+	spin_lock_irqsave(&obj->child_list_lock, flags);
+	sync_timeline_get(obj);
+	fence_init(&pt->base, &timeline_fence_ops, &obj->child_list_lock,
+		   obj->context, value);
+	list_add_tail(&pt->child_list, &obj->child_list_head);
+	INIT_LIST_HEAD(&pt->active_list);
+	spin_unlock_irqrestore(&obj->child_list_lock, flags);
+	return pt;
+}
+
+static const char *timeline_fence_get_driver_name(struct fence *fence)
+{
+	return "sw_sync";
+}
+
+static const char *timeline_fence_get_timeline_name(struct fence *fence)
+{
+	struct sync_timeline *parent = fence_parent(fence);
+
+	return parent->name;
+}
+
+static void timeline_fence_release(struct fence *fence)
+{
+	struct sync_pt *pt = fence_to_sync_pt(fence);
+	struct sync_timeline *parent = fence_parent(fence);
+	unsigned long flags;
+
+	spin_lock_irqsave(fence->lock, flags);
+	list_del(&pt->child_list);
+	if (!list_empty(&pt->active_list))
+		list_del(&pt->active_list);
+	spin_unlock_irqrestore(fence->lock, flags);
+
+	sync_timeline_put(parent);
+	fence_free(fence);
+}
+
+static bool timeline_fence_signaled(struct fence *fence)
+{
+	struct sync_timeline *parent = fence_parent(fence);
+
+	return (fence->seqno > parent->value) ? false : true;
+}
+
+static bool timeline_fence_enable_signaling(struct fence *fence)
+{
+	struct sync_pt *pt = fence_to_sync_pt(fence);
+	struct sync_timeline *parent = fence_parent(fence);
+
+	if (timeline_fence_signaled(fence))
+		return false;
+
+	list_add_tail(&pt->active_list, &parent->active_list_head);
+	return true;
+}
+
+static void timeline_fence_value_str(struct fence *fence,
+				    char *str, int size)
+{
+	snprintf(str, size, "%d", fence->seqno);
+}
+
+static void timeline_fence_timeline_value_str(struct fence *fence,
+					     char *str, int size)
+{
+	struct sync_timeline *parent = fence_parent(fence);
+
+	snprintf(str, size, "%d", parent->value);
+}
+
+static const struct fence_ops timeline_fence_ops = {
+	.get_driver_name = timeline_fence_get_driver_name,
+	.get_timeline_name = timeline_fence_get_timeline_name,
+	.enable_signaling = timeline_fence_enable_signaling,
+	.signaled = timeline_fence_signaled,
+	.wait = fence_default_wait,
+	.release = timeline_fence_release,
+	.fence_value_str = timeline_fence_value_str,
+	.timeline_value_str = timeline_fence_timeline_value_str,
+};
+
+/*
+ * *WARNING*
+ *
+ * improper use of this can result in deadlocking kernel drivers from userspace.
+ */
+
+/* opening sw_sync create a new sync obj */
+static int sw_sync_debugfs_open(struct inode *inode, struct file *file)
+{
+	struct sync_timeline *obj;
+	char task_comm[TASK_COMM_LEN];
+
+	get_task_comm(task_comm, current);
+
+	obj = sync_timeline_create(task_comm);
+	if (!obj)
+		return -ENOMEM;
+
+	file->private_data = obj;
+
+	return 0;
+}
+
+static int sw_sync_debugfs_release(struct inode *inode, struct file *file)
+{
+	struct sync_timeline *obj = file->private_data;
+
+	smp_wmb();
+
+	sync_timeline_put(obj);
+	return 0;
+}
+
+static long sw_sync_ioctl_create_fence(struct sync_timeline *obj,
+				       unsigned long arg)
+{
+	int fd = get_unused_fd_flags(O_CLOEXEC);
+	int err;
+	struct sync_pt *pt;
+	struct sync_file *sync_file;
+	struct sw_sync_create_fence_data data;
+
+	if (fd < 0)
+		return fd;
+
+	if (copy_from_user(&data, (void __user *)arg, sizeof(data))) {
+		err = -EFAULT;
+		goto err;
+	}
+
+	pt = sync_pt_create(obj, sizeof(*pt), data.value);
+	if (!pt) {
+		err = -ENOMEM;
+		goto err;
+	}
+
+	sync_file = sync_file_create(&pt->base);
+	if (!sync_file) {
+		fence_put(&pt->base);
+		err = -ENOMEM;
+		goto err;
+	}
+
+	data.fence = fd;
+	if (copy_to_user((void __user *)arg, &data, sizeof(data))) {
+		fput(sync_file->file);
+		err = -EFAULT;
+		goto err;
+	}
+
+	fd_install(fd, sync_file->file);
+
+	return 0;
+
+err:
+	put_unused_fd(fd);
+	return err;
+}
+
+static long sw_sync_ioctl_inc(struct sync_timeline *obj, unsigned long arg)
+{
+	u32 value;
+
+	if (copy_from_user(&value, (void __user *)arg, sizeof(value)))
+		return -EFAULT;
+
+	sync_timeline_signal(obj, value);
+
+	return 0;
+}
+
+static long sw_sync_ioctl(struct file *file, unsigned int cmd,
+			  unsigned long arg)
+{
+	struct sync_timeline *obj = file->private_data;
+
+	switch (cmd) {
+	case SW_SYNC_IOC_CREATE_FENCE:
+		return sw_sync_ioctl_create_fence(obj, arg);
+
+	case SW_SYNC_IOC_INC:
+		return sw_sync_ioctl_inc(obj, arg);
+
+	default:
+		return -ENOTTY;
+	}
+}
+
+const struct file_operations sw_sync_debugfs_fops = {
+	.open           = sw_sync_debugfs_open,
+	.release        = sw_sync_debugfs_release,
+	.unlocked_ioctl = sw_sync_ioctl,
+	.compat_ioctl	= sw_sync_ioctl,
+};
diff --git a/drivers/dma-buf/sync_debug.c b/drivers/dma-buf/sync_debug.c
new file mode 100644
index 0000000..fab9520
--- /dev/null
+++ b/drivers/dma-buf/sync_debug.c
@@ -0,0 +1,230 @@
+/*
+ * Sync File validation framework and debug information
+ *
+ * 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 "sync_debug.h"
+
+static struct dentry *dbgfs;
+
+static LIST_HEAD(sync_timeline_list_head);
+static DEFINE_SPINLOCK(sync_timeline_list_lock);
+static LIST_HEAD(sync_file_list_head);
+static DEFINE_SPINLOCK(sync_file_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_file_debug_add(struct sync_file *sync_file)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&sync_file_list_lock, flags);
+	list_add_tail(&sync_file->sync_file_list, &sync_file_list_head);
+	spin_unlock_irqrestore(&sync_file_list_lock, flags);
+}
+
+void sync_file_debug_remove(struct sync_file *sync_file)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&sync_file_list_lock, flags);
+	list_del(&sync_file->sync_file_list);
+	spin_unlock_irqrestore(&sync_file_list_lock, flags);
+}
+
+static const char *sync_status_str(int status)
+{
+	if (status == 0)
+		return "signaled";
+
+	if (status > 0)
+		return "active";
+
+	return "error";
+}
+
+static void sync_print_fence(struct seq_file *s, struct fence *fence, bool show)
+{
+	int status = 1;
+	struct sync_timeline *parent = fence_parent(fence);
+
+	if (fence_is_signaled_locked(fence))
+		status = fence->status;
+
+	seq_printf(s, "  %s%sfence %s",
+		   show ? parent->name : "",
+		   show ? "_" : "",
+		   sync_status_str(status));
+
+	if (status <= 0) {
+		struct timespec64 ts64 =
+			ktime_to_timespec64(fence->timestamp);
+
+		seq_printf(s, "@%lld.%09ld", (s64)ts64.tv_sec, ts64.tv_nsec);
+	}
+
+	if (fence->ops->timeline_value_str &&
+		fence->ops->fence_value_str) {
+		char value[64];
+		bool success;
+
+		fence->ops->fence_value_str(fence, value, sizeof(value));
+		success = strlen(value);
+
+		if (success) {
+			seq_printf(s, ": %s", value);
+
+			fence->ops->timeline_value_str(fence, value,
+						       sizeof(value));
+
+			if (strlen(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: %d\n", obj->name, obj->value);
+
+	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_fence(s, &pt->base, false);
+	}
+	spin_unlock_irqrestore(&obj->child_list_lock, flags);
+}
+
+static void sync_print_sync_file(struct seq_file *s,
+				  struct sync_file *sync_file)
+{
+	int i;
+
+	seq_printf(s, "[%p] %s: %s\n", sync_file, sync_file->name,
+		   sync_status_str(atomic_read(&sync_file->status)));
+
+	for (i = 0; i < sync_file->num_fences; ++i)
+		sync_print_fence(s, sync_file->cbs[i].fence, true);
+}
+
+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_file_list_lock, flags);
+	list_for_each(pos, &sync_file_list_head) {
+		struct sync_file *sync_file =
+			container_of(pos, struct sync_file, sync_file_list);
+
+		sync_print_sync_file(s, sync_file);
+		seq_puts(s, "\n");
+	}
+	spin_unlock_irqrestore(&sync_file_list_lock, flags);
+	return 0;
+}
+
+static int sync_info_debugfs_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, sync_debugfs_show, inode->i_private);
+}
+
+static const struct file_operations sync_info_debugfs_fops = {
+	.open           = sync_info_debugfs_open,
+	.read           = seq_read,
+	.llseek         = seq_lseek,
+	.release        = single_release,
+};
+
+static __init int sync_debugfs_init(void)
+{
+	dbgfs = debugfs_create_dir("sync", NULL);
+
+	/*
+	 * The debugfs files won't ever get removed and thus, there is
+	 * no need to protect it against removal races. The use of
+	 * debugfs_create_file_unsafe() is actually safe here.
+	 */
+	debugfs_create_file_unsafe("info", 0444, dbgfs, NULL,
+				   &sync_info_debugfs_fops);
+	debugfs_create_file_unsafe("sw_sync", 0644, dbgfs, NULL,
+				   &sw_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);
+		}
+	}
+}
diff --git a/drivers/dma-buf/sync_debug.h b/drivers/dma-buf/sync_debug.h
new file mode 100644
index 0000000..ee3c27b
--- /dev/null
+++ b/drivers/dma-buf/sync_debug.h
@@ -0,0 +1,69 @@
+/*
+ * Sync File validation framework
+ *
+ * Copyright (C) 2012 Google, Inc.
+ *
+ * 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.
+ *
+ */
+
+#ifndef _LINUX_SYNC_H
+#define _LINUX_SYNC_H
+
+#include <linux/list.h>
+#include <linux/spinlock.h>
+#include <linux/fence.h>
+
+#include <linux/sync_file.h>
+#include <uapi/linux/sync_file.h>
+
+struct sync_timeline {
+	struct kref		kref;
+	char			name[32];
+
+	/* protected by child_list_lock */
+	u64			context;
+	int			value;
+
+	struct list_head	child_list_head;
+	spinlock_t		child_list_lock;
+
+	struct list_head	active_list_head;
+
+	struct list_head	sync_timeline_list;
+};
+
+static inline struct sync_timeline *fence_parent(struct fence *fence)
+{
+	return container_of(fence->lock, struct sync_timeline,
+			    child_list_lock);
+}
+
+struct sync_pt {
+	struct fence base;
+	struct list_head child_list;
+	struct list_head active_list;
+};
+
+#ifdef CONFIG_SW_SYNC
+
+extern const struct file_operations sw_sync_debugfs_fops;
+
+void sync_timeline_debug_add(struct sync_timeline *obj);
+void sync_timeline_debug_remove(struct sync_timeline *obj);
+void sync_file_debug_add(struct sync_file *fence);
+void sync_file_debug_remove(struct sync_file *fence);
+void sync_dump(void);
+
+#else
+# define sync_timeline_debug_add(obj)
+# define sync_timeline_debug_remove(obj)
+# define sync_file_debug_add(fence)
+# define sync_file_debug_remove(fence)
+# define sync_dump()
+#endif
+
+#endif /* _LINUX_SYNC_H */
diff --git a/drivers/dma-buf/sync_trace.h b/drivers/dma-buf/sync_trace.h
new file mode 100644
index 0000000..d13d59f
--- /dev/null
+++ b/drivers/dma-buf/sync_trace.h
@@ -0,0 +1,32 @@
+#undef TRACE_SYSTEM
+#define TRACE_INCLUDE_PATH ../../drivers/dma-buf
+#define TRACE_SYSTEM sync_trace
+
+#if !defined(_TRACE_SYNC_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_SYNC_H
+
+#include "sync_debug.h"
+#include <linux/tracepoint.h>
+
+TRACE_EVENT(sync_timeline,
+	TP_PROTO(struct sync_timeline *timeline),
+
+	TP_ARGS(timeline),
+
+	TP_STRUCT__entry(
+			__string(name, timeline->name)
+			__field(u32, value)
+	),
+
+	TP_fast_assign(
+			__assign_str(name, timeline->name);
+			__entry->value = timeline->value;
+	),
+
+	TP_printk("name=%s value=%d", __get_str(name), __entry->value)
+);
+
+#endif /* if !defined(_TRACE_SYNC_H) || defined(TRACE_HEADER_MULTI_READ) */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
diff --git a/drivers/staging/android/Kconfig b/drivers/staging/android/Kconfig
index 06e41d2..6c00d6f 100644
--- a/drivers/staging/android/Kconfig
+++ b/drivers/staging/android/Kconfig
@@ -24,19 +24,6 @@ config ANDROID_LOW_MEMORY_KILLER
 	  scripts (/init.rc), and it defines priority values with minimum free memory size
 	  for each priority.
 
-config SW_SYNC
-	bool "Software synchronization framework"
-	default n
-	depends on SYNC_FILE
-	depends on DEBUG_FS
-	---help---
-	  A sync object driver that uses a 32bit counter to coordinate
-	  synchronization.  Useful when there is no hardware primitive backing
-	  the synchronization.
-
-	  WARNING: improper use of this can result in deadlocking kernel
-	  drivers from userspace. Intended for test and debug only.
-
 source "drivers/staging/android/ion/Kconfig"
 
 endif # if ANDROID
diff --git a/drivers/staging/android/Makefile b/drivers/staging/android/Makefile
index 7ca61b7..7ed1be7 100644
--- a/drivers/staging/android/Makefile
+++ b/drivers/staging/android/Makefile
@@ -4,4 +4,3 @@ obj-y					+= ion/
 
 obj-$(CONFIG_ASHMEM)			+= ashmem.o
 obj-$(CONFIG_ANDROID_LOW_MEMORY_KILLER)	+= lowmemorykiller.o
-obj-$(CONFIG_SW_SYNC)			+= sw_sync.o sync_debug.o
diff --git a/drivers/staging/android/sw_sync.c b/drivers/staging/android/sw_sync.c
deleted file mode 100644
index 2ac5608..0000000
--- a/drivers/staging/android/sw_sync.c
+++ /dev/null
@@ -1,349 +0,0 @@
-/*
- * Sync File validation framework
- *
- * 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/file.h>
-#include <linux/fs.h>
-#include <linux/uaccess.h>
-#include <linux/slab.h>
-#include <linux/sync_file.h>
-
-#include "sync_debug.h"
-
-#define CREATE_TRACE_POINTS
-#include "sync_trace.h"
-
-/*
- * SW SYNC validation framework
- *
- * A sync object driver that uses a 32bit counter to coordinate
- * synchronization.  Useful when there is no hardware primitive backing
- * the synchronization.
- *
- * To start the framework just open:
- *
- * <debugfs>/sync/sw_sync
- *
- * That will create a sync timeline, all fences created under this timeline
- * file descriptor will belong to the this timeline.
- *
- * The 'sw_sync' file can be opened many times as to create different
- * timelines.
- *
- * Fences can be created with SW_SYNC_IOC_CREATE_FENCE ioctl with struct
- * sw_sync_ioctl_create_fence as parameter.
- *
- * To increment the timeline counter SW_SYNC_IOC_INC ioctl should be used
- * with the increment as u32. This will update the last signaled value
- * from the timeline and signal any fence that has seqno, smaller of equal
- * it.
- *
- * struct sw_sync_ioctl_create_fence
- * @value:	the seqno to initiate the fence with
- * @name:	the name of the new sync point
- * @fence:	return the fd of the new sync_file with the created fence
- */
-struct sw_sync_create_fence_data {
-	__u32	value;
-	char	name[32];
-	__s32	fence; /* fd of new fence */
-};
-
-#define SW_SYNC_IOC_MAGIC	'W'
-
-#define SW_SYNC_IOC_CREATE_FENCE	_IOWR(SW_SYNC_IOC_MAGIC, 0,\
-		struct sw_sync_create_fence_data)
-
-#define SW_SYNC_IOC_INC			_IOW(SW_SYNC_IOC_MAGIC, 1, __u32)
-
-static const struct fence_ops timeline_fence_ops;
-
-static inline struct sync_pt *fence_to_sync_pt(struct fence *fence)
-{
-	if (fence->ops != &timeline_fence_ops)
-		return NULL;
-	return container_of(fence, struct sync_pt, base);
-}
-
-struct sync_timeline *sync_timeline_create(const char *name)
-{
-	struct sync_timeline *obj;
-
-	obj = kzalloc(sizeof(*obj), GFP_KERNEL);
-	if (!obj)
-		return NULL;
-
-	kref_init(&obj->kref);
-	obj->context = fence_context_alloc(1);
-	strlcpy(obj->name, name, sizeof(obj->name));
-
-	INIT_LIST_HEAD(&obj->child_list_head);
-	INIT_LIST_HEAD(&obj->active_list_head);
-	spin_lock_init(&obj->child_list_lock);
-
-	sync_timeline_debug_add(obj);
-
-	return obj;
-}
-
-static void sync_timeline_free(struct kref *kref)
-{
-	struct sync_timeline *obj =
-		container_of(kref, struct sync_timeline, kref);
-
-	sync_timeline_debug_remove(obj);
-
-	kfree(obj);
-}
-
-static void sync_timeline_get(struct sync_timeline *obj)
-{
-	kref_get(&obj->kref);
-}
-
-static void sync_timeline_put(struct sync_timeline *obj)
-{
-	kref_put(&obj->kref, sync_timeline_free);
-}
-
-static void sync_timeline_signal(struct sync_timeline *obj, unsigned int inc)
-{
-	unsigned long flags;
-	struct sync_pt *pt, *next;
-
-	trace_sync_timeline(obj);
-
-	spin_lock_irqsave(&obj->child_list_lock, flags);
-
-	obj->value += inc;
-
-	list_for_each_entry_safe(pt, next, &obj->active_list_head,
-				 active_list) {
-		if (fence_is_signaled_locked(&pt->base))
-			list_del_init(&pt->active_list);
-	}
-
-	spin_unlock_irqrestore(&obj->child_list_lock, flags);
-}
-
-static struct sync_pt *sync_pt_create(struct sync_timeline *obj, int size,
-			     unsigned int value)
-{
-	unsigned long flags;
-	struct sync_pt *pt;
-
-	if (size < sizeof(*pt))
-		return NULL;
-
-	pt = kzalloc(size, GFP_KERNEL);
-	if (!pt)
-		return NULL;
-
-	spin_lock_irqsave(&obj->child_list_lock, flags);
-	sync_timeline_get(obj);
-	fence_init(&pt->base, &timeline_fence_ops, &obj->child_list_lock,
-		   obj->context, value);
-	list_add_tail(&pt->child_list, &obj->child_list_head);
-	INIT_LIST_HEAD(&pt->active_list);
-	spin_unlock_irqrestore(&obj->child_list_lock, flags);
-	return pt;
-}
-
-static const char *timeline_fence_get_driver_name(struct fence *fence)
-{
-	return "sw_sync";
-}
-
-static const char *timeline_fence_get_timeline_name(struct fence *fence)
-{
-	struct sync_timeline *parent = fence_parent(fence);
-
-	return parent->name;
-}
-
-static void timeline_fence_release(struct fence *fence)
-{
-	struct sync_pt *pt = fence_to_sync_pt(fence);
-	struct sync_timeline *parent = fence_parent(fence);
-	unsigned long flags;
-
-	spin_lock_irqsave(fence->lock, flags);
-	list_del(&pt->child_list);
-	if (!list_empty(&pt->active_list))
-		list_del(&pt->active_list);
-	spin_unlock_irqrestore(fence->lock, flags);
-
-	sync_timeline_put(parent);
-	fence_free(fence);
-}
-
-static bool timeline_fence_signaled(struct fence *fence)
-{
-	struct sync_timeline *parent = fence_parent(fence);
-
-	return (fence->seqno > parent->value) ? false : true;
-}
-
-static bool timeline_fence_enable_signaling(struct fence *fence)
-{
-	struct sync_pt *pt = fence_to_sync_pt(fence);
-	struct sync_timeline *parent = fence_parent(fence);
-
-	if (timeline_fence_signaled(fence))
-		return false;
-
-	list_add_tail(&pt->active_list, &parent->active_list_head);
-	return true;
-}
-
-static void timeline_fence_value_str(struct fence *fence,
-				    char *str, int size)
-{
-	snprintf(str, size, "%d", fence->seqno);
-}
-
-static void timeline_fence_timeline_value_str(struct fence *fence,
-					     char *str, int size)
-{
-	struct sync_timeline *parent = fence_parent(fence);
-
-	snprintf(str, size, "%d", parent->value);
-}
-
-static const struct fence_ops timeline_fence_ops = {
-	.get_driver_name = timeline_fence_get_driver_name,
-	.get_timeline_name = timeline_fence_get_timeline_name,
-	.enable_signaling = timeline_fence_enable_signaling,
-	.signaled = timeline_fence_signaled,
-	.wait = fence_default_wait,
-	.release = timeline_fence_release,
-	.fence_value_str = timeline_fence_value_str,
-	.timeline_value_str = timeline_fence_timeline_value_str,
-};
-
-/*
- * *WARNING*
- *
- * improper use of this can result in deadlocking kernel drivers from userspace.
- */
-
-/* opening sw_sync create a new sync obj */
-static int sw_sync_debugfs_open(struct inode *inode, struct file *file)
-{
-	struct sync_timeline *obj;
-	char task_comm[TASK_COMM_LEN];
-
-	get_task_comm(task_comm, current);
-
-	obj = sync_timeline_create(task_comm);
-	if (!obj)
-		return -ENOMEM;
-
-	file->private_data = obj;
-
-	return 0;
-}
-
-static int sw_sync_debugfs_release(struct inode *inode, struct file *file)
-{
-	struct sync_timeline *obj = file->private_data;
-
-	smp_wmb();
-
-	sync_timeline_put(obj);
-	return 0;
-}
-
-static long sw_sync_ioctl_create_fence(struct sync_timeline *obj,
-				       unsigned long arg)
-{
-	int fd = get_unused_fd_flags(O_CLOEXEC);
-	int err;
-	struct sync_pt *pt;
-	struct sync_file *sync_file;
-	struct sw_sync_create_fence_data data;
-
-	if (fd < 0)
-		return fd;
-
-	if (copy_from_user(&data, (void __user *)arg, sizeof(data))) {
-		err = -EFAULT;
-		goto err;
-	}
-
-	pt = sync_pt_create(obj, sizeof(*pt), data.value);
-	if (!pt) {
-		err = -ENOMEM;
-		goto err;
-	}
-
-	sync_file = sync_file_create(&pt->base);
-	if (!sync_file) {
-		fence_put(&pt->base);
-		err = -ENOMEM;
-		goto err;
-	}
-
-	data.fence = fd;
-	if (copy_to_user((void __user *)arg, &data, sizeof(data))) {
-		fput(sync_file->file);
-		err = -EFAULT;
-		goto err;
-	}
-
-	fd_install(fd, sync_file->file);
-
-	return 0;
-
-err:
-	put_unused_fd(fd);
-	return err;
-}
-
-static long sw_sync_ioctl_inc(struct sync_timeline *obj, unsigned long arg)
-{
-	u32 value;
-
-	if (copy_from_user(&value, (void __user *)arg, sizeof(value)))
-		return -EFAULT;
-
-	sync_timeline_signal(obj, value);
-
-	return 0;
-}
-
-static long sw_sync_ioctl(struct file *file, unsigned int cmd,
-			  unsigned long arg)
-{
-	struct sync_timeline *obj = file->private_data;
-
-	switch (cmd) {
-	case SW_SYNC_IOC_CREATE_FENCE:
-		return sw_sync_ioctl_create_fence(obj, arg);
-
-	case SW_SYNC_IOC_INC:
-		return sw_sync_ioctl_inc(obj, arg);
-
-	default:
-		return -ENOTTY;
-	}
-}
-
-const struct file_operations sw_sync_debugfs_fops = {
-	.open           = sw_sync_debugfs_open,
-	.release        = sw_sync_debugfs_release,
-	.unlocked_ioctl = sw_sync_ioctl,
-	.compat_ioctl	= sw_sync_ioctl,
-};
diff --git a/drivers/staging/android/sync_debug.c b/drivers/staging/android/sync_debug.c
deleted file mode 100644
index fab9520..0000000
--- a/drivers/staging/android/sync_debug.c
+++ /dev/null
@@ -1,230 +0,0 @@
-/*
- * Sync File validation framework and debug information
- *
- * 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 "sync_debug.h"
-
-static struct dentry *dbgfs;
-
-static LIST_HEAD(sync_timeline_list_head);
-static DEFINE_SPINLOCK(sync_timeline_list_lock);
-static LIST_HEAD(sync_file_list_head);
-static DEFINE_SPINLOCK(sync_file_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_file_debug_add(struct sync_file *sync_file)
-{
-	unsigned long flags;
-
-	spin_lock_irqsave(&sync_file_list_lock, flags);
-	list_add_tail(&sync_file->sync_file_list, &sync_file_list_head);
-	spin_unlock_irqrestore(&sync_file_list_lock, flags);
-}
-
-void sync_file_debug_remove(struct sync_file *sync_file)
-{
-	unsigned long flags;
-
-	spin_lock_irqsave(&sync_file_list_lock, flags);
-	list_del(&sync_file->sync_file_list);
-	spin_unlock_irqrestore(&sync_file_list_lock, flags);
-}
-
-static const char *sync_status_str(int status)
-{
-	if (status == 0)
-		return "signaled";
-
-	if (status > 0)
-		return "active";
-
-	return "error";
-}
-
-static void sync_print_fence(struct seq_file *s, struct fence *fence, bool show)
-{
-	int status = 1;
-	struct sync_timeline *parent = fence_parent(fence);
-
-	if (fence_is_signaled_locked(fence))
-		status = fence->status;
-
-	seq_printf(s, "  %s%sfence %s",
-		   show ? parent->name : "",
-		   show ? "_" : "",
-		   sync_status_str(status));
-
-	if (status <= 0) {
-		struct timespec64 ts64 =
-			ktime_to_timespec64(fence->timestamp);
-
-		seq_printf(s, "@%lld.%09ld", (s64)ts64.tv_sec, ts64.tv_nsec);
-	}
-
-	if (fence->ops->timeline_value_str &&
-		fence->ops->fence_value_str) {
-		char value[64];
-		bool success;
-
-		fence->ops->fence_value_str(fence, value, sizeof(value));
-		success = strlen(value);
-
-		if (success) {
-			seq_printf(s, ": %s", value);
-
-			fence->ops->timeline_value_str(fence, value,
-						       sizeof(value));
-
-			if (strlen(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: %d\n", obj->name, obj->value);
-
-	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_fence(s, &pt->base, false);
-	}
-	spin_unlock_irqrestore(&obj->child_list_lock, flags);
-}
-
-static void sync_print_sync_file(struct seq_file *s,
-				  struct sync_file *sync_file)
-{
-	int i;
-
-	seq_printf(s, "[%p] %s: %s\n", sync_file, sync_file->name,
-		   sync_status_str(atomic_read(&sync_file->status)));
-
-	for (i = 0; i < sync_file->num_fences; ++i)
-		sync_print_fence(s, sync_file->cbs[i].fence, true);
-}
-
-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_file_list_lock, flags);
-	list_for_each(pos, &sync_file_list_head) {
-		struct sync_file *sync_file =
-			container_of(pos, struct sync_file, sync_file_list);
-
-		sync_print_sync_file(s, sync_file);
-		seq_puts(s, "\n");
-	}
-	spin_unlock_irqrestore(&sync_file_list_lock, flags);
-	return 0;
-}
-
-static int sync_info_debugfs_open(struct inode *inode, struct file *file)
-{
-	return single_open(file, sync_debugfs_show, inode->i_private);
-}
-
-static const struct file_operations sync_info_debugfs_fops = {
-	.open           = sync_info_debugfs_open,
-	.read           = seq_read,
-	.llseek         = seq_lseek,
-	.release        = single_release,
-};
-
-static __init int sync_debugfs_init(void)
-{
-	dbgfs = debugfs_create_dir("sync", NULL);
-
-	/*
-	 * The debugfs files won't ever get removed and thus, there is
-	 * no need to protect it against removal races. The use of
-	 * debugfs_create_file_unsafe() is actually safe here.
-	 */
-	debugfs_create_file_unsafe("info", 0444, dbgfs, NULL,
-				   &sync_info_debugfs_fops);
-	debugfs_create_file_unsafe("sw_sync", 0644, dbgfs, NULL,
-				   &sw_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);
-		}
-	}
-}
diff --git a/drivers/staging/android/sync_debug.h b/drivers/staging/android/sync_debug.h
deleted file mode 100644
index ee3c27b..0000000
--- a/drivers/staging/android/sync_debug.h
+++ /dev/null
@@ -1,69 +0,0 @@
-/*
- * Sync File validation framework
- *
- * Copyright (C) 2012 Google, Inc.
- *
- * 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.
- *
- */
-
-#ifndef _LINUX_SYNC_H
-#define _LINUX_SYNC_H
-
-#include <linux/list.h>
-#include <linux/spinlock.h>
-#include <linux/fence.h>
-
-#include <linux/sync_file.h>
-#include <uapi/linux/sync_file.h>
-
-struct sync_timeline {
-	struct kref		kref;
-	char			name[32];
-
-	/* protected by child_list_lock */
-	u64			context;
-	int			value;
-
-	struct list_head	child_list_head;
-	spinlock_t		child_list_lock;
-
-	struct list_head	active_list_head;
-
-	struct list_head	sync_timeline_list;
-};
-
-static inline struct sync_timeline *fence_parent(struct fence *fence)
-{
-	return container_of(fence->lock, struct sync_timeline,
-			    child_list_lock);
-}
-
-struct sync_pt {
-	struct fence base;
-	struct list_head child_list;
-	struct list_head active_list;
-};
-
-#ifdef CONFIG_SW_SYNC
-
-extern const struct file_operations sw_sync_debugfs_fops;
-
-void sync_timeline_debug_add(struct sync_timeline *obj);
-void sync_timeline_debug_remove(struct sync_timeline *obj);
-void sync_file_debug_add(struct sync_file *fence);
-void sync_file_debug_remove(struct sync_file *fence);
-void sync_dump(void);
-
-#else
-# define sync_timeline_debug_add(obj)
-# define sync_timeline_debug_remove(obj)
-# define sync_file_debug_add(fence)
-# define sync_file_debug_remove(fence)
-# define sync_dump()
-#endif
-
-#endif /* _LINUX_SYNC_H */
diff --git a/drivers/staging/android/sync_trace.h b/drivers/staging/android/sync_trace.h
deleted file mode 100644
index ea485f7..0000000
--- a/drivers/staging/android/sync_trace.h
+++ /dev/null
@@ -1,32 +0,0 @@
-#undef TRACE_SYSTEM
-#define TRACE_INCLUDE_PATH ../../drivers/staging/android
-#define TRACE_SYSTEM sync_trace
-
-#if !defined(_TRACE_SYNC_H) || defined(TRACE_HEADER_MULTI_READ)
-#define _TRACE_SYNC_H
-
-#include "sync_debug.h"
-#include <linux/tracepoint.h>
-
-TRACE_EVENT(sync_timeline,
-	TP_PROTO(struct sync_timeline *timeline),
-
-	TP_ARGS(timeline),
-
-	TP_STRUCT__entry(
-			__string(name, timeline->name)
-			__field(u32, value)
-	),
-
-	TP_fast_assign(
-			__assign_str(name, timeline->name);
-			__entry->value = timeline->value;
-	),
-
-	TP_printk("name=%s value=%d", __get_str(name), __entry->value)
-);
-
-#endif /* if !defined(_TRACE_SYNC_H) || defined(TRACE_HEADER_MULTI_READ) */
-
-/* This part must be outside protection */
-#include <trace/define_trace.h>
-- 
2.5.5

Re: [PATCH v2 1/6] staging/android: remove doc from sw_sync

[Pavel Machek]

On Mon 2016-08-08 18:24:17, Gustavo Padovan wrote:
> From: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
> 
> SW_SYNC should never be used by other pieces of the kernel apart from
> sync_debug as it is only a Sync File Validation Framework, so hide any
> info to avoid confuse this with a standard kernel internal API.

> Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>

NAK.

It is unclear for what the code does, removing the docs is not going to help.

If it should not be used, document that it should not be used.. but not remove
the docs.

> -/**
> - * sync_timeline_signal() - signal a status change on a sync_timeline
> - * @obj:	sync_timeline to signal
> - * @inc:	num to increment on timeline->value
> - *
> - * A sync implementation should call this any time one of it's fences
> - * has signaled or has an error condition.
> - */
>  static void sync_timeline_signal(struct sync_timeline *obj, unsigned int inc)
>  {

And as the functions are static... there's little danger that someone will misuse them.

										Pavel

Re: [PATCH v2 0/6] de-stage SW_SYNC validation frawework

[Eric Engestrom]

On Mon, Aug 08, 2016 at 06:24:16PM -0300, Gustavo Padovan wrote:
> From: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
> 
> Hi Greg,
> 
> This is the last step in the Sync Framwork de-stage task. It de-stage
> the SW_SYNC validation framework and the sync_debug info debugfs file.
> 
> The first 2 patches are clean up and improvements and the rest is preparation
> to de-stage and then finally the actual de-stage.
> 
> v2: 
>  - add documentation about the SW_SYNC ioctl API (comments from Pavel Machek)
>  - remove for now patch to add sync_pt name to debugfs
> 
> Please review,
> 
> Gustavo
> 
> ---
> Gustavo Padovan (6):
>   staging/android: remove doc from sw_sync
>   staging/android: do not let userspace trigger WARN_ON
>   staging/android: move trace/sync.h to sync_trace.h
>   staging/android: prepare sw_sync files for de-staging
>   staging/android: add Doc for SW_SYNC ioctl interface
>   dma-buf/sw_sync: de-stage SW_SYNC
> 
>  drivers/dma-buf/Kconfig              |  13 ++
>  drivers/dma-buf/Makefile             |   1 +
>  drivers/dma-buf/sw_sync.c            | 349 +++++++++++++++++++++++++++++++++++
>  drivers/dma-buf/sync_debug.c         | 230 +++++++++++++++++++++++
>  drivers/dma-buf/sync_debug.h         |  69 +++++++
>  drivers/dma-buf/sync_trace.h         |  32 ++++
>  drivers/staging/android/Kconfig      |  13 --
>  drivers/staging/android/Makefile     |   1 -
>  drivers/staging/android/sw_sync.c    | 344 ----------------------------------
>  drivers/staging/android/sync_debug.c | 230 -----------------------
>  drivers/staging/android/sync_debug.h |  84 ---------
>  drivers/staging/android/trace/sync.h |  32 ----
>  12 files changed, 694 insertions(+), 704 deletions(-)

>  create mode 100644 drivers/dma-buf/sw_sync.c
>  create mode 100644 drivers/dma-buf/sync_debug.c
>  create mode 100644 drivers/dma-buf/sync_debug.h
>  create mode 100644 drivers/dma-buf/sync_trace.h
>  delete mode 100644 drivers/staging/android/sw_sync.c
>  delete mode 100644 drivers/staging/android/sync_debug.c
>  delete mode 100644 drivers/staging/android/sync_debug.h
>  delete mode 100644 drivers/staging/android/trace/sync.h

When you send your next revision, could you use `git format-patch -M`?
A good 95% of the lines in these patches aren't actually modified, just
moved around, which makes it much harder to spot the actual changes :)

Cheers,
  Eric

> 
> -- 
> 2.5.5

Re: [PATCH v2 3/6] staging/android: move trace/sync.h to sync_trace.h

[Eric Engestrom]

On Mon, Aug 08, 2016 at 06:24:19PM -0300, Gustavo Padovan wrote:
> From: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
> 
> The common behaviour for trace headers is to have them in the same folder
> they are used, instead of creating a special trace/ directory.
> 
> Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>

Reviewed-by: Eric Engestrom <eric.engestrom@imgtec.com>

> ---
>  drivers/staging/android/sw_sync.c    |  2 +-
>  drivers/staging/android/sync_trace.h | 32 ++++++++++++++++++++++++++++++++
>  drivers/staging/android/trace/sync.h | 32 --------------------------------
>  3 files changed, 33 insertions(+), 33 deletions(-)
>  create mode 100644 drivers/staging/android/sync_trace.h
>  delete mode 100644 drivers/staging/android/trace/sync.h
> 
> diff --git a/drivers/staging/android/sw_sync.c b/drivers/staging/android/sw_sync.c
> index ad0bb1a..745597b 100644
> --- a/drivers/staging/android/sw_sync.c
> +++ b/drivers/staging/android/sw_sync.c
> @@ -23,7 +23,7 @@
>  #include "sync_debug.h"
>  
>  #define CREATE_TRACE_POINTS
> -#include "trace/sync.h"
> +#include "sync_trace.h"
>  
>  struct sw_sync_create_fence_data {
>  	__u32	value;
> diff --git a/drivers/staging/android/sync_trace.h b/drivers/staging/android/sync_trace.h
> new file mode 100644
> index 0000000..ea485f7
> --- /dev/null
> +++ b/drivers/staging/android/sync_trace.h
> @@ -0,0 +1,32 @@
> +#undef TRACE_SYSTEM
> +#define TRACE_INCLUDE_PATH ../../drivers/staging/android
> +#define TRACE_SYSTEM sync_trace
> +
> +#if !defined(_TRACE_SYNC_H) || defined(TRACE_HEADER_MULTI_READ)
> +#define _TRACE_SYNC_H
> +
> +#include "sync_debug.h"
> +#include <linux/tracepoint.h>
> +
> +TRACE_EVENT(sync_timeline,
> +	TP_PROTO(struct sync_timeline *timeline),
> +
> +	TP_ARGS(timeline),
> +
> +	TP_STRUCT__entry(
> +			__string(name, timeline->name)
> +			__field(u32, value)
> +	),
> +
> +	TP_fast_assign(
> +			__assign_str(name, timeline->name);
> +			__entry->value = timeline->value;
> +	),
> +
> +	TP_printk("name=%s value=%d", __get_str(name), __entry->value)
> +);
> +
> +#endif /* if !defined(_TRACE_SYNC_H) || defined(TRACE_HEADER_MULTI_READ) */
> +
> +/* This part must be outside protection */
> +#include <trace/define_trace.h>
> diff --git a/drivers/staging/android/trace/sync.h b/drivers/staging/android/trace/sync.h
> deleted file mode 100644
> index 6b5ce96..0000000
> --- a/drivers/staging/android/trace/sync.h
> +++ /dev/null
> @@ -1,32 +0,0 @@
> -#undef TRACE_SYSTEM
> -#define TRACE_INCLUDE_PATH ../../drivers/staging/android/trace
> -#define TRACE_SYSTEM sync
> -
> -#if !defined(_TRACE_SYNC_H) || defined(TRACE_HEADER_MULTI_READ)
> -#define _TRACE_SYNC_H
> -
> -#include "../sync_debug.h"
> -#include <linux/tracepoint.h>
> -
> -TRACE_EVENT(sync_timeline,
> -	TP_PROTO(struct sync_timeline *timeline),
> -
> -	TP_ARGS(timeline),
> -
> -	TP_STRUCT__entry(
> -			__string(name, timeline->name)
> -			__field(u32, value)
> -	),
> -
> -	TP_fast_assign(
> -			__assign_str(name, timeline->name);
> -			__entry->value = timeline->value;
> -	),
> -
> -	TP_printk("name=%s value=%d", __get_str(name), __entry->value)
> -);
> -
> -#endif /* if !defined(_TRACE_SYNC_H) || defined(TRACE_HEADER_MULTI_READ) */
> -
> -/* This part must be outside protection */
> -#include <trace/define_trace.h>
> -- 
> 2.5.5

Re: [PATCH v2 4/6] staging/android: prepare sw_sync files for de-staging

[Eric Engestrom]

On Mon, Aug 08, 2016 at 06:24:20PM -0300, Gustavo Padovan wrote:
> From: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
> 
> remove file paths in the comments and add short description about each
> file.
> 
> v2: remove file paths instead of just change them.
> 
> Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
> ---
>  drivers/staging/android/sw_sync.c    | 2 +-
>  drivers/staging/android/sync_debug.c | 2 +-
>  drivers/staging/android/sync_debug.h | 2 +-
>  3 files changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/staging/android/sw_sync.c b/drivers/staging/android/sw_sync.c
> index 745597b..43491b6 100644
> --- a/drivers/staging/android/sw_sync.c
> +++ b/drivers/staging/android/sw_sync.c
> @@ -1,5 +1,5 @@
>  /*
> - * drivers/dma-buf/sw_sync.c
> + * Sync File validation framework
>   *
>   * Copyright (C) 2012 Google, Inc.
>   *
> diff --git a/drivers/staging/android/sync_debug.c b/drivers/staging/android/sync_debug.c
> index 4c5a855..fab9520 100644
> --- a/drivers/staging/android/sync_debug.c
> +++ b/drivers/staging/android/sync_debug.c
> @@ -1,5 +1,5 @@
>  /*
> - * drivers/base/sync.c
> + * Sync File validation framework and debug information
>   *
>   * Copyright (C) 2012 Google, Inc.
>   *
> diff --git a/drivers/staging/android/sync_debug.h b/drivers/staging/android/sync_debug.h
> index 5b82cf8..ee3c27b 100644
> --- a/drivers/staging/android/sync_debug.h
> +++ b/drivers/staging/android/sync_debug.h
> @@ -1,5 +1,5 @@
>  /*
> - * include/linux/sync.h
> + * Sync File validation framework

"and debug information"

With that added,
Reviewed-by: Eric Engestrom <eric.engestrom@imgtec.com>

>   *
>   * Copyright (C) 2012 Google, Inc.
>   *
> -- 
> 2.5.5

Re: [PATCH v2 5/6] staging/android: add Doc for SW_SYNC ioctl interface

[Eric Engestrom]

On Mon, Aug 08, 2016 at 06:24:21PM -0300, Gustavo Padovan wrote:
> From: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
> 
> This interface is hidden from kernel headers and it is intended for use
> only for testing. So testers would have to add the ioctl information
> internally. This is to prevent misuse of this feature.
> 
> Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
> ---
>  drivers/staging/android/sw_sync.c | 31 +++++++++++++++++++++++++++++++
>  1 file changed, 31 insertions(+)
> 
> diff --git a/drivers/staging/android/sw_sync.c b/drivers/staging/android/sw_sync.c
> index 43491b6..2ac5608 100644
> --- a/drivers/staging/android/sw_sync.c
> +++ b/drivers/staging/android/sw_sync.c
> @@ -25,6 +25,36 @@
>  #define CREATE_TRACE_POINTS
>  #include "sync_trace.h"
>  
> +/*
> + * SW SYNC validation framework
> + *
> + * A sync object driver that uses a 32bit counter to coordinate
> + * synchronization.  Useful when there is no hardware primitive backing
> + * the synchronization.
> + *
> + * To start the framework just open:
> + *
> + * <debugfs>/sync/sw_sync
> + *
> + * That will create a sync timeline, all fences created under this timeline
> + * file descriptor will belong to the this timeline.
> + *
> + * The 'sw_sync' file can be opened many times as to create different
> + * timelines.
> + *
> + * Fences can be created with SW_SYNC_IOC_CREATE_FENCE ioctl with struct
> + * sw_sync_ioctl_create_fence as parameter.
> + *
> + * To increment the timeline counter SW_SYNC_IOC_INC ioctl should be used
> + * with the increment as u32. This will update the last signaled value
> + * from the timeline and signal any fence that has seqno, smaller of equal
> + * it.

This last paragraph could use some love: comma before "SW_SYNC_IOC_INC",
"that has seqno smaller or equal to it."

> + *
> + * struct sw_sync_ioctl_create_fence
> + * @value:	the seqno to initiate the fence with

s/initiate/initialise/

With these fixed,
Reviewed-by: Eric Engestrom <eric.engestrom@imgtec.com>

> + * @name:	the name of the new sync point
> + * @fence:	return the fd of the new sync_file with the created fence
> + */
>  struct sw_sync_create_fence_data {
>  	__u32	value;
>  	char	name[32];
> @@ -35,6 +65,7 @@ struct sw_sync_create_fence_data {
>  
>  #define SW_SYNC_IOC_CREATE_FENCE	_IOWR(SW_SYNC_IOC_MAGIC, 0,\
>  		struct sw_sync_create_fence_data)
> +
>  #define SW_SYNC_IOC_INC			_IOW(SW_SYNC_IOC_MAGIC, 1, __u32)
>  
>  static const struct fence_ops timeline_fence_ops;
> -- 
> 2.5.5

Re: [PATCH v2 6/6] dma-buf/sw_sync: de-stage SW_SYNC

[Eric Engestrom]

On Mon, Aug 08, 2016 at 06:24:22PM -0300, Gustavo Padovan wrote:
> From: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
> 
> SW_SYNC allows to run tests on the sync_file framework via debugfs on
> 
> <debugfs>/sync/sw_sync
> 
> Opening and closing the file triggers creation and release of a sync
> timeline. To create fences on this timeline the SW_SYNC_IOC_CREATE_FENCE
> ioctl should be used. To increment the timeline value use SW_SYNC_IOC_INC.
> 
> Also it exports Sync information on
> 
> <debugfs>/sync/info
> 
> Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>

Reviewed-by: Eric Engestrom <eric.engestrom@imgtec.com>

> ---
>  drivers/dma-buf/Kconfig              |  13 ++
>  drivers/dma-buf/Makefile             |   1 +
>  drivers/dma-buf/sw_sync.c            | 349 +++++++++++++++++++++++++++++++++++
>  drivers/dma-buf/sync_debug.c         | 230 +++++++++++++++++++++++
>  drivers/dma-buf/sync_debug.h         |  69 +++++++
>  drivers/dma-buf/sync_trace.h         |  32 ++++
>  drivers/staging/android/Kconfig      |  13 --
>  drivers/staging/android/Makefile     |   1 -
>  drivers/staging/android/sw_sync.c    | 349 -----------------------------------
>  drivers/staging/android/sync_debug.c | 230 -----------------------
>  drivers/staging/android/sync_debug.h |  69 -------
>  drivers/staging/android/sync_trace.h |  32 ----
>  12 files changed, 694 insertions(+), 694 deletions(-)
>  create mode 100644 drivers/dma-buf/sw_sync.c
>  create mode 100644 drivers/dma-buf/sync_debug.c
>  create mode 100644 drivers/dma-buf/sync_debug.h
>  create mode 100644 drivers/dma-buf/sync_trace.h
>  delete mode 100644 drivers/staging/android/sw_sync.c
>  delete mode 100644 drivers/staging/android/sync_debug.c
>  delete mode 100644 drivers/staging/android/sync_debug.h
>  delete mode 100644 drivers/staging/android/sync_trace.h
> 

[snip]

Re: [PATCH v2 1/6] staging/android: remove doc from sw_sync

[Gustavo Padovan]

Hi Pavel,

2016-08-09 Pavel Machek <pavel@ucw.cz>:

> On Mon 2016-08-08 18:24:17, Gustavo Padovan wrote:
> > From: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
> > 
> > SW_SYNC should never be used by other pieces of the kernel apart from
> > sync_debug as it is only a Sync File Validation Framework, so hide any
> > info to avoid confuse this with a standard kernel internal API.
> 
> > Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
> 
> NAK.
> 
> It is unclear for what the code does, removing the docs is not going to help.
> 
> If it should not be used, document that it should not be used.. but not remove
> the docs.

Okay, I'll skip this patch.

Re: [PATCH v2 0/6] de-stage SW_SYNC validation frawework

[Gustavo Padovan]

Hi Eric,

2016-08-11 Eric Engestrom <eric.engestrom@imgtec.com>:

> On Mon, Aug 08, 2016 at 06:24:16PM -0300, Gustavo Padovan wrote:
> > From: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
> > 
> > Hi Greg,
> > 
> > This is the last step in the Sync Framwork de-stage task. It de-stage
> > the SW_SYNC validation framework and the sync_debug info debugfs file.
> > 
> > The first 2 patches are clean up and improvements and the rest is preparation
> > to de-stage and then finally the actual de-stage.
> > 
> > v2: 
> >  - add documentation about the SW_SYNC ioctl API (comments from Pavel Machek)
> >  - remove for now patch to add sync_pt name to debugfs
> > 
> > Please review,
> > 
> > Gustavo
> > 
> > ---
> > Gustavo Padovan (6):
> >   staging/android: remove doc from sw_sync
> >   staging/android: do not let userspace trigger WARN_ON
> >   staging/android: move trace/sync.h to sync_trace.h
> >   staging/android: prepare sw_sync files for de-staging
> >   staging/android: add Doc for SW_SYNC ioctl interface
> >   dma-buf/sw_sync: de-stage SW_SYNC
> > 
> >  drivers/dma-buf/Kconfig              |  13 ++
> >  drivers/dma-buf/Makefile             |   1 +
> >  drivers/dma-buf/sw_sync.c            | 349 +++++++++++++++++++++++++++++++++++
> >  drivers/dma-buf/sync_debug.c         | 230 +++++++++++++++++++++++
> >  drivers/dma-buf/sync_debug.h         |  69 +++++++
> >  drivers/dma-buf/sync_trace.h         |  32 ++++
> >  drivers/staging/android/Kconfig      |  13 --
> >  drivers/staging/android/Makefile     |   1 -
> >  drivers/staging/android/sw_sync.c    | 344 ----------------------------------
> >  drivers/staging/android/sync_debug.c | 230 -----------------------
> >  drivers/staging/android/sync_debug.h |  84 ---------
> >  drivers/staging/android/trace/sync.h |  32 ----
> >  12 files changed, 694 insertions(+), 704 deletions(-)
> 
> >  create mode 100644 drivers/dma-buf/sw_sync.c
> >  create mode 100644 drivers/dma-buf/sync_debug.c
> >  create mode 100644 drivers/dma-buf/sync_debug.h
> >  create mode 100644 drivers/dma-buf/sync_trace.h
> >  delete mode 100644 drivers/staging/android/sw_sync.c
> >  delete mode 100644 drivers/staging/android/sync_debug.c
> >  delete mode 100644 drivers/staging/android/sync_debug.h
> >  delete mode 100644 drivers/staging/android/trace/sync.h
> 
> When you send your next revision, could you use `git format-patch -M`?
> A good 95% of the lines in these patches aren't actually modified, just
> moved around, which makes it much harder to spot the actual changes :)

Sure, I was doing this for previous revisions, but forgot to do it for
this one.

	Gustavo