[libcamera-devel] [PATCH] libcamera: Improve Request life cycle tracking

[Jacopo Mondi]

The current logging to track the status of a Request when running the
Android camera HAL provide the following information:

When a Request is queued to libcamera:
HAL camera_device.cpp:1776 '\_SB_.PCI0.I2C2.CAM0': Queueing Request to libcamera with 1 HAL streams

When a Request completes:
Request request.cpp:268 Request has completed - cookie: 138508601719648

The queueing of a Request reports the number of streams it contains
while the completion of a Request reports the address of the associated
cookie.

This makes very hard to keep track of what Requests have completed, as
the logging associated with a queue/complete event does not allow to identify
a Request easily.

Add two more printouts to make it easier to track a Request life cycle.

The result looks like the following trace:

Request request.cpp:92 Created request - cookie: 138508601718368
HAL camera_device.cpp:1776 '\_SB_.PCI0.I2C2.CAM0': Queueing Request to libcamera with 1 HAL streams
HAL camera_device.cpp:1813 '\_SB_.PCI0.I2C2.CAM0': 0 - (640x480)[0x00000022] -> (640x480)[NV12] (direct)
...
...
Request request.cpp:268 Request has completed - cookie: 138508601718368
HAL camera_device.cpp:1866 '\_SB_.PCI0.I2C2.CAM0': Request completed by libcamera with 1 streams

Signed-off-by: Jacopo Mondi <jacopo at jmondi.org>
---
 src/android/camera_device.cpp | 3 +++
 src/libcamera/request.cpp     | 2 ++
 2 files changed, 5 insertions(+)

diff --git a/src/android/camera_device.cpp b/src/android/camera_device.cpp
index a9634f4e4198..513f000b1854 100644
--- a/src/android/camera_device.cpp
+++ b/src/android/camera_device.cpp
@@ -1863,6 +1863,9 @@ void CameraDevice::requestComplete(Request *request)
 		status = CAMERA3_BUFFER_STATUS_ERROR;
 	}
 
+	LOG(HAL, Debug) << "Request completed by libcamera with "
+			<< descriptor->numBuffers_ << " streams";
+
 	/*
 	 * \todo The timestamp used for the metadata is currently always taken
 	 * from the first buffer (which may be the first stream) in the Request.
diff --git a/src/libcamera/request.cpp b/src/libcamera/request.cpp
index a68684ef9fd3..e561ce1d5d0e 100644
--- a/src/libcamera/request.cpp
+++ b/src/libcamera/request.cpp
@@ -88,6 +88,8 @@ Request::Request(Camera *camera, uint64_t cookie)
 	metadata_ = new ControlList(controls::controls);
 
 	LIBCAMERA_TRACEPOINT(request_construct, this);
+
+	LOG(Request, Debug) << "Created request - cookie: " << cookie_;
 }
 
 Request::~Request()
-- 
2.30.0