[PATCH v2 1/3] [media] v4l2: use event class to deduplicate v4l2 trace events

[PATCH v2 1/3] [media] v4l2: use event class to deduplicate v4l2 trace events

[Philipp Zabel]

Trace events with exactly the same parameters and trace output, such as
v4l2_qbuf and v4l2_dqbuf, are supposed to use the DECLARE_EVENT_CLASS and
DEFINE_EVENT macros instead of duplicated TRACE_EVENT macro calls.

Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
---
 include/trace/events/v4l2.h | 160 +++++++++++++++++++++-----------------------
 1 file changed, 78 insertions(+), 82 deletions(-)

diff --git a/include/trace/events/v4l2.h b/include/trace/events/v4l2.h
index 89d0497..4c88a32 100644
--- a/include/trace/events/v4l2.h
+++ b/include/trace/events/v4l2.h
@@ -93,90 +93,86 @@ SHOW_FIELD
 		{ V4L2_TC_USERBITS_USERDEFINED,	"USERBITS_USERDEFINED" }, \
 		{ V4L2_TC_USERBITS_8BITCHARS,	"USERBITS_8BITCHARS" })
 
-#define V4L2_TRACE_EVENT(event_name)					\
-	TRACE_EVENT(event_name,						\
-		TP_PROTO(int minor, struct v4l2_buffer *buf),		\
-									\
-		TP_ARGS(minor, buf),					\
-									\
-		TP_STRUCT__entry(					\
-			__field(int, minor)				\
-			__field(u32, index)				\
-			__field(u32, type)				\
-			__field(u32, bytesused)				\
-			__field(u32, flags)				\
-			__field(u32, field)				\
-			__field(s64, timestamp)				\
-			__field(u32, timecode_type)			\
-			__field(u32, timecode_flags)			\
-			__field(u8, timecode_frames)			\
-			__field(u8, timecode_seconds)			\
-			__field(u8, timecode_minutes)			\
-			__field(u8, timecode_hours)			\
-			__field(u8, timecode_userbits0)			\
-			__field(u8, timecode_userbits1)			\
-			__field(u8, timecode_userbits2)			\
-			__field(u8, timecode_userbits3)			\
-			__field(u32, sequence)				\
-		),							\
-									\
-		TP_fast_assign(						\
-			__entry->minor = minor;				\
-			__entry->index = buf->index;			\
-			__entry->type = buf->type;			\
-			__entry->bytesused = buf->bytesused;		\
-			__entry->flags = buf->flags;			\
-			__entry->field = buf->field;			\
-			__entry->timestamp =				\
-				timeval_to_ns(&buf->timestamp);		\
-			__entry->timecode_type = buf->timecode.type;	\
-			__entry->timecode_flags = buf->timecode.flags;	\
-			__entry->timecode_frames =			\
-				buf->timecode.frames;			\
-			__entry->timecode_seconds =			\
-				buf->timecode.seconds;			\
-			__entry->timecode_minutes =			\
-				buf->timecode.minutes;			\
-			__entry->timecode_hours = buf->timecode.hours;	\
-			__entry->timecode_userbits0 =			\
-				buf->timecode.userbits[0];		\
-			__entry->timecode_userbits1 =			\
-				buf->timecode.userbits[1];		\
-			__entry->timecode_userbits2 =			\
-				buf->timecode.userbits[2];		\
-			__entry->timecode_userbits3 =			\
-				buf->timecode.userbits[3];		\
-			__entry->sequence = buf->sequence;		\
-		),							\
-									\
-		TP_printk("minor = %d, index = %u, type = %s, "		\
-			  "bytesused = %u, flags = %s, "		\
-			  "field = %s, timestamp = %llu, timecode = { "	\
-			  "type = %s, flags = %s, frames = %u, "	\
-			  "seconds = %u, minutes = %u, hours = %u, "	\
-			  "userbits = { %u %u %u %u } }, "		\
-			  "sequence = %u", __entry->minor,		\
-			  __entry->index, show_type(__entry->type),	\
-			  __entry->bytesused,				\
-			  show_flags(__entry->flags),			\
-			  show_field(__entry->field),			\
-			  __entry->timestamp,				\
-			  show_timecode_type(__entry->timecode_type),	\
-			  show_timecode_flags(__entry->timecode_flags),	\
-			  __entry->timecode_frames,			\
-			  __entry->timecode_seconds,			\
-			  __entry->timecode_minutes,			\
-			  __entry->timecode_hours,			\
-			  __entry->timecode_userbits0,			\
-			  __entry->timecode_userbits1,			\
-			  __entry->timecode_userbits2,			\
-			  __entry->timecode_userbits3,			\
-			  __entry->sequence				\
-		)							\
+DECLARE_EVENT_CLASS(v4l2_event_class,
+	TP_PROTO(int minor, struct v4l2_buffer *buf),
+
+	TP_ARGS(minor, buf),
+
+	TP_STRUCT__entry(
+		__field(int, minor)
+		__field(u32, index)
+		__field(u32, type)
+		__field(u32, bytesused)
+		__field(u32, flags)
+		__field(u32, field)
+		__field(s64, timestamp)
+		__field(u32, timecode_type)
+		__field(u32, timecode_flags)
+		__field(u8, timecode_frames)
+		__field(u8, timecode_seconds)
+		__field(u8, timecode_minutes)
+		__field(u8, timecode_hours)
+		__field(u8, timecode_userbits0)
+		__field(u8, timecode_userbits1)
+		__field(u8, timecode_userbits2)
+		__field(u8, timecode_userbits3)
+		__field(u32, sequence)
+	),
+
+	TP_fast_assign(
+		__entry->minor = minor;
+		__entry->index = buf->index;
+		__entry->type = buf->type;
+		__entry->bytesused = buf->bytesused;
+		__entry->flags = buf->flags;
+		__entry->field = buf->field;
+		__entry->timestamp = timeval_to_ns(&buf->timestamp);
+		__entry->timecode_type = buf->timecode.type;
+		__entry->timecode_flags = buf->timecode.flags;
+		__entry->timecode_frames = buf->timecode.frames;
+		__entry->timecode_seconds = buf->timecode.seconds;
+		__entry->timecode_minutes = buf->timecode.minutes;
+		__entry->timecode_hours = buf->timecode.hours;
+		__entry->timecode_userbits0 = buf->timecode.userbits[0];
+		__entry->timecode_userbits1 = buf->timecode.userbits[1];
+		__entry->timecode_userbits2 = buf->timecode.userbits[2];
+		__entry->timecode_userbits3 = buf->timecode.userbits[3];
+		__entry->sequence = buf->sequence;
+	),
+
+	TP_printk("minor = %d, index = %u, type = %s, bytesused = %u, "
+		  "flags = %s, field = %s, timestamp = %llu, "
+		  "timecode = { type = %s, flags = %s, frames = %u, "
+		  "seconds = %u, minutes = %u, hours = %u, "
+		  "userbits = { %u %u %u %u } }, sequence = %u", __entry->minor,
+		  __entry->index, show_type(__entry->type),
+		  __entry->bytesused,
+		  show_flags(__entry->flags),
+		  show_field(__entry->field),
+		  __entry->timestamp,
+		  show_timecode_type(__entry->timecode_type),
+		  show_timecode_flags(__entry->timecode_flags),
+		  __entry->timecode_frames,
+		  __entry->timecode_seconds,
+		  __entry->timecode_minutes,
+		  __entry->timecode_hours,
+		  __entry->timecode_userbits0,
+		  __entry->timecode_userbits1,
+		  __entry->timecode_userbits2,
+		  __entry->timecode_userbits3,
+		  __entry->sequence
 	)
+)
 
-V4L2_TRACE_EVENT(v4l2_dqbuf);
-V4L2_TRACE_EVENT(v4l2_qbuf);
+DEFINE_EVENT(v4l2_event_class, v4l2_dqbuf,
+	TP_PROTO(int minor, struct v4l2_buffer *buf),
+	TP_ARGS(minor, buf)
+);
+
+DEFINE_EVENT(v4l2_event_class, v4l2_qbuf,
+	TP_PROTO(int minor, struct v4l2_buffer *buf),
+	TP_ARGS(minor, buf)
+);
 
 #endif /* if !defined(_TRACE_V4L2_H) || defined(TRACE_HEADER_MULTI_READ) */
 
-- 
2.1.4

[PATCH v2 2/3] [media] v4l2-mem2mem: set the queue owner field just as vb2_ioctl_reqbufs does

[Philipp Zabel]

The queue owner will be used by videobuf2 trace events to determine and
record the device minor number. It is set in v4l2_m2m_reqbufs instead of
v4l2_m2m_ioctl_reqbufs because several drivers implement their own
vidioc_reqbufs handlers that still call v4l2_m2m_reqbufs directly.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
---
 drivers/media/v4l2-core/v4l2-mem2mem.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/media/v4l2-core/v4l2-mem2mem.c b/drivers/media/v4l2-core/v4l2-mem2mem.c
index dc853e5..af8d6b4 100644
--- a/drivers/media/v4l2-core/v4l2-mem2mem.c
+++ b/drivers/media/v4l2-core/v4l2-mem2mem.c
@@ -357,9 +357,16 @@ int v4l2_m2m_reqbufs(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
 		     struct v4l2_requestbuffers *reqbufs)
 {
 	struct vb2_queue *vq;
+	int ret;
 
 	vq = v4l2_m2m_get_vq(m2m_ctx, reqbufs->type);
-	return vb2_reqbufs(vq, reqbufs);
+	ret = vb2_reqbufs(vq, reqbufs);
+	/* If count == 0, then the owner has released all buffers and he
+	   is no longer owner of the queue. Otherwise we have an owner. */
+	if (ret == 0)
+		vq->owner = reqbufs->count ? file->private_data : NULL;
+
+	return ret;
 }
 EXPORT_SYMBOL_GPL(v4l2_m2m_reqbufs);
 
-- 
2.1.4

[PATCH v2 3/3] [media] videobuf2: add trace events

[Philipp Zabel]

Add videobuf2 specific vb2_qbuf and vb2_dqbuf trace events that mirror the
v4l2_qbuf and v4l2_dqbuf trace events, only they include additional
information about queue fill state and are emitted right before the buffer
is enqueued in the driver or userspace is woken up. This allows to make
sense of the timeline of trace events in combination with others that might
be triggered by __enqueue_in_driver.

Also two new trace events vb2_buf_queue and vb2_buf_done are added,
allowing to trace the handover between videobuf2 framework and driver.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
---
Changes since v1:
 - use event class for similar trace events, as requested by Steven Rostedt
---
 drivers/media/v4l2-core/videobuf2-core.c | 11 ++++
 include/trace/events/v4l2.h              | 97 ++++++++++++++++++++++++++++++++
 2 files changed, 108 insertions(+)

diff --git a/drivers/media/v4l2-core/videobuf2-core.c b/drivers/media/v4l2-core/videobuf2-core.c
index 93b3154..b866a6b 100644
--- a/drivers/media/v4l2-core/videobuf2-core.c
+++ b/drivers/media/v4l2-core/videobuf2-core.c
@@ -30,6 +30,8 @@
 #include <media/v4l2-common.h>
 #include <media/videobuf2-core.h>
 
+#include <trace/events/v4l2.h>
+
 static int debug;
 module_param(debug, int, 0644);
 
@@ -1207,6 +1209,8 @@ void vb2_buffer_done(struct vb2_buffer *vb, enum vb2_buffer_state state)
 	atomic_dec(&q->owned_by_drv_count);
 	spin_unlock_irqrestore(&q->done_lock, flags);
 
+	trace_vb2_buf_done(q, vb);
+
 	if (state == VB2_BUF_STATE_QUEUED) {
 		if (q->start_streaming_called)
 			__enqueue_in_driver(vb);
@@ -1629,6 +1633,8 @@ static void __enqueue_in_driver(struct vb2_buffer *vb)
 	vb->state = VB2_BUF_STATE_ACTIVE;
 	atomic_inc(&q->owned_by_drv_count);
 
+	trace_vb2_buf_queue(q, vb);
+
 	/* sync buffers */
 	for (plane = 0; plane < vb->num_planes; ++plane)
 		call_void_memop(vb, prepare, vb->planes[plane].mem_priv);
@@ -1878,6 +1884,8 @@ static int vb2_internal_qbuf(struct vb2_queue *q, struct v4l2_buffer *b)
 			vb->v4l2_buf.timecode = b->timecode;
 	}
 
+	trace_vb2_qbuf(q, vb);
+
 	/*
 	 * If already streaming, give the buffer to driver for processing.
 	 * If not, the buffer will be given to driver on next streamon.
@@ -2123,6 +2131,9 @@ static int vb2_internal_dqbuf(struct vb2_queue *q, struct v4l2_buffer *b, bool n
 	/* Remove from videobuf queue */
 	list_del(&vb->queued_entry);
 	q->queued_count--;
+
+	trace_vb2_dqbuf(q, vb);
+
 	if (!V4L2_TYPE_IS_OUTPUT(q->type) &&
 	    vb->v4l2_buf.flags & V4L2_BUF_FLAG_LAST)
 		q->last_buffer_dequeued = true;
diff --git a/include/trace/events/v4l2.h b/include/trace/events/v4l2.h
index 4c88a32..d9e9aeb 100644
--- a/include/trace/events/v4l2.h
+++ b/include/trace/events/v4l2.h
@@ -174,6 +174,103 @@ DEFINE_EVENT(v4l2_event_class, v4l2_qbuf,
 	TP_ARGS(minor, buf)
 );
 
+DECLARE_EVENT_CLASS(vb2_event_class,
+	TP_PROTO(struct vb2_queue *q, struct vb2_buffer *vb),
+	TP_ARGS(q, vb),
+
+	TP_STRUCT__entry(
+		__field(int, minor)
+		__field(u32, queued_count)
+		__field(int, owned_by_drv_count)
+		__field(u32, index)
+		__field(u32, type)
+		__field(u32, bytesused)
+		__field(u32, flags)
+		__field(u32, field)
+		__field(s64, timestamp)
+		__field(u32, timecode_type)
+		__field(u32, timecode_flags)
+		__field(u8, timecode_frames)
+		__field(u8, timecode_seconds)
+		__field(u8, timecode_minutes)
+		__field(u8, timecode_hours)
+		__field(u8, timecode_userbits0)
+		__field(u8, timecode_userbits1)
+		__field(u8, timecode_userbits2)
+		__field(u8, timecode_userbits3)
+		__field(u32, sequence)
+	),
+
+	TP_fast_assign(
+		__entry->minor = q->owner ? q->owner->vdev->minor : -1;
+		__entry->queued_count = q->queued_count;
+		__entry->owned_by_drv_count =
+			atomic_read(&q->owned_by_drv_count);
+		__entry->index = vb->v4l2_buf.index;
+		__entry->type = vb->v4l2_buf.type;
+		__entry->bytesused = vb->v4l2_buf.bytesused;
+		__entry->flags = vb->v4l2_buf.flags;
+		__entry->field = vb->v4l2_buf.field;
+		__entry->timestamp = timeval_to_ns(&vb->v4l2_buf.timestamp);
+		__entry->timecode_type = vb->v4l2_buf.timecode.type;
+		__entry->timecode_flags = vb->v4l2_buf.timecode.flags;
+		__entry->timecode_frames = vb->v4l2_buf.timecode.frames;
+		__entry->timecode_seconds = vb->v4l2_buf.timecode.seconds;
+		__entry->timecode_minutes = vb->v4l2_buf.timecode.minutes;
+		__entry->timecode_hours = vb->v4l2_buf.timecode.hours;
+		__entry->timecode_userbits0 = vb->v4l2_buf.timecode.userbits[0];
+		__entry->timecode_userbits1 = vb->v4l2_buf.timecode.userbits[1];
+		__entry->timecode_userbits2 = vb->v4l2_buf.timecode.userbits[2];
+		__entry->timecode_userbits3 = vb->v4l2_buf.timecode.userbits[3];
+		__entry->sequence = vb->v4l2_buf.sequence;
+	),
+
+	TP_printk("minor = %d, queued = %u, owned_by_drv = %d, index = %u, "
+		  "type = %s, bytesused = %u, flags = %s, field = %s, "
+		  "timestamp = %llu, timecode = { type = %s, flags = %s, "
+		  "frames = %u, seconds = %u, minutes = %u, hours = %u, "
+		  "userbits = { %u %u %u %u } }, sequence = %u", __entry->minor,
+		  __entry->queued_count,
+		  __entry->owned_by_drv_count,
+		  __entry->index, show_type(__entry->type),
+		  __entry->bytesused,
+		  show_flags(__entry->flags),
+		  show_field(__entry->field),
+		  __entry->timestamp,
+		  show_timecode_type(__entry->timecode_type),
+		  show_timecode_flags(__entry->timecode_flags),
+		  __entry->timecode_frames,
+		  __entry->timecode_seconds,
+		  __entry->timecode_minutes,
+		  __entry->timecode_hours,
+		  __entry->timecode_userbits0,
+		  __entry->timecode_userbits1,
+		  __entry->timecode_userbits2,
+		  __entry->timecode_userbits3,
+		  __entry->sequence
+	)
+)
+
+DEFINE_EVENT(vb2_event_class, vb2_buf_done,
+	TP_PROTO(struct vb2_queue *q, struct vb2_buffer *vb),
+	TP_ARGS(q, vb)
+);
+
+DEFINE_EVENT(vb2_event_class, vb2_buf_queue,
+	TP_PROTO(struct vb2_queue *q, struct vb2_buffer *vb),
+	TP_ARGS(q, vb)
+);
+
+DEFINE_EVENT(vb2_event_class, vb2_dqbuf,
+	TP_PROTO(struct vb2_queue *q, struct vb2_buffer *vb),
+	TP_ARGS(q, vb)
+);
+
+DEFINE_EVENT(vb2_event_class, vb2_qbuf,
+	TP_PROTO(struct vb2_queue *q, struct vb2_buffer *vb),
+	TP_ARGS(q, vb)
+);
+
 #endif /* if !defined(_TRACE_V4L2_H) || defined(TRACE_HEADER_MULTI_READ) */
 
 /* This part must be outside protection */
-- 
2.1.4