[libcamera-devel,v1,2/3] gstreamer: Fix concurrent access issues to CameraManager
diff mbox series

Message ID 20210825211852.1207168-3-nicolas@ndufresne.ca
State Accepted
Headers show
Series
  • Fix Gnome Cheese and multiple camera
Related show

Commit Message

Nicolas Dufresne Aug. 25, 2021, 9:18 p.m. UTC 
From: Nicolas Dufresne <nicolas.dufresne@collabora.com>

It's not allowed to have multiple instances of CameraManager. This
requirement is not easy for GStreamer were the device monitor and
the camerasrc, or two camerasrc instances don't usually have any
interaction between each other. This this by implementing a minimalist
singleton around CameraManager constructor and start()/stop()
operations.

Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
---
 src/gstreamer/gstlibcamera-utils.cpp   | 31 ++++++++++++++++++++++++++
 src/gstreamer/gstlibcamera-utils.h     |  6 +++--
 src/gstreamer/gstlibcameraprovider.cpp | 22 ++----------------
 src/gstreamer/gstlibcamerasrc.cpp      | 11 +++++----
 4 files changed, 42 insertions(+), 28 deletions(-)

Comments

Laurent Pinchart Aug. 25, 2021, 11:18 p.m. UTC | #1 
Hi Nicolas,

Thank you for the patch.

On Wed, Aug 25, 2021 at 05:18:51PM -0400, Nicolas Dufresne wrote:
> From: Nicolas Dufresne <nicolas.dufresne@collabora.com>
> 
> It's not allowed to have multiple instances of CameraManager. This
> requirement is not easy for GStreamer were the device monitor and
> the camerasrc, or two camerasrc instances don't usually have any
> interaction between each other. This this by implementing a minimalist

s/This this/Fix this/ ?

> singleton around CameraManager constructor and start()/stop()
> operations.
> 
> Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
> ---
>  src/gstreamer/gstlibcamera-utils.cpp   | 31 ++++++++++++++++++++++++++
>  src/gstreamer/gstlibcamera-utils.h     |  6 +++--
>  src/gstreamer/gstlibcameraprovider.cpp | 22 ++----------------
>  src/gstreamer/gstlibcamerasrc.cpp      | 11 +++++----
>  4 files changed, 42 insertions(+), 28 deletions(-)
> 
> diff --git a/src/gstreamer/gstlibcamera-utils.cpp b/src/gstreamer/gstlibcamera-utils.cpp
> index 007d6a64..34b64c4a 100644
> --- a/src/gstreamer/gstlibcamera-utils.cpp
> +++ b/src/gstreamer/gstlibcamera-utils.cpp
> @@ -221,3 +221,34 @@ gst_libcamera_resume_task(GstTask *task)
>  		GST_TASK_SIGNAL(task);
>  	}
>  }
> +
> +G_LOCK_DEFINE_STATIC(cm_singleton_lock);
> +std::weak_ptr<CameraManager> cm_singleton_ptr;
> +
> +void _cm_deleter(CameraManager *cm)
> +{
> +	g_print("Delete CameraManager\n");
> +	cm->stop();
> +	delete cm;

The CameraManager destructor calls stop(), so if you don't care much
about the g_print(), you could drop this function.

> +}
> +
> +std::shared_ptr<CameraManager>
> +gst_libcamera_get_camera_mananger(int &ret)
> +{
> +	std::shared_ptr<CameraManager> cm;
> +
> +	G_LOCK(cm_singleton_lock);
> +
> +	cm = cm_singleton_ptr.lock();
> +	if (cm_singleton_ptr.expired()) {

I think you could write this

	cm = cm_singleton_ptr.lock();
	if (cm) {

as std::weak_ptr<>::lock() return a null std::shared_ptr<> if it has
expired.

> +		std::shared_ptr<CameraManager> ptr(new CameraManager(), _cm_deleter);
> +		cm_singleton_ptr = cm = ptr;

And there's no need for the local ptr variable here, you can write

		cm = std::shared_ptr<CameraManager>(new CameraManager(), _cm_deleter);
		cm_singleton_ptr = cm;

If you don't care about the deleter, it could also become

		cm = std::make_shared<CameraManager>();
		cm_singleton_ptr = cm;

> +		ret = cm->start();
> +	} else {
> +		ret = 0;
> +	}
> +
> +	G_UNLOCK(cm_singleton_lock);
> +
> +	return cm;
> +}
> diff --git a/src/gstreamer/gstlibcamera-utils.h b/src/gstreamer/gstlibcamera-utils.h
> index 2b3f26b6..67a06db3 100644
> --- a/src/gstreamer/gstlibcamera-utils.h
> +++ b/src/gstreamer/gstlibcamera-utils.h
> @@ -9,16 +9,18 @@
>  #ifndef __GST_LIBCAMERA_UTILS_H__
>  #define __GST_LIBCAMERA_UTILS_H__
>  
> +#include <libcamera/camera_manager.h>
> +#include <libcamera/stream.h>
> +
>  #include <gst/gst.h>
>  #include <gst/video/video.h>
>  
> -#include <libcamera/stream.h>
> -
>  GstCaps *gst_libcamera_stream_formats_to_caps(const libcamera::StreamFormats &formats);
>  GstCaps *gst_libcamera_stream_configuration_to_caps(const libcamera::StreamConfiguration &stream_cfg);
>  void gst_libcamera_configure_stream_from_caps(libcamera::StreamConfiguration &stream_cfg,
>  					      GstCaps *caps);
>  void gst_libcamera_resume_task(GstTask *task);
> +std::shared_ptr<libcamera::CameraManager> gst_libcamera_get_camera_mananger(int &ret);
>  
>  /**
>   * \class GLibLocker
> diff --git a/src/gstreamer/gstlibcameraprovider.cpp b/src/gstreamer/gstlibcameraprovider.cpp
> index 29da6c32..948ba0d1 100644
> --- a/src/gstreamer/gstlibcameraprovider.cpp
> +++ b/src/gstreamer/gstlibcameraprovider.cpp
> @@ -158,7 +158,6 @@ gst_libcamera_device_new(const std::shared_ptr<Camera> &camera)
>  
>  struct _GstLibcameraProvider {
>  	GstDeviceProvider parent;
> -	CameraManager *cm;
>  };

Is this constructed on demand to call probe() and then immediately
destroyed that it makes no sense anymore to cache the pointer ?

>  
>  G_DEFINE_TYPE_WITH_CODE(GstLibcameraProvider, gst_libcamera_provider,
> @@ -170,7 +169,7 @@ static GList *
>  gst_libcamera_provider_probe(GstDeviceProvider *provider)
>  {
>  	GstLibcameraProvider *self = GST_LIBCAMERA_PROVIDER(provider);
> -	CameraManager *cm = self->cm;
> +	std::shared_ptr<CameraManager> cm;
>  	GList *devices = nullptr;
>  	gint ret;
>  
> @@ -181,7 +180,7 @@ gst_libcamera_provider_probe(GstDeviceProvider *provider)
>  	 * gains monitoring support. Meanwhile we need to cycle start()/stop()
>  	 * to ensure every probe() calls return the latest list.
>  	 */
> -	ret = cm->start();
> +	cm = gst_libcamera_get_camera_mananger(ret);
>  	if (ret) {
>  		GST_ERROR_OBJECT(self, "Failed to retrieve device list: %s",
>  				 g_strerror(-ret));
> @@ -194,8 +193,6 @@ gst_libcamera_provider_probe(GstDeviceProvider *provider)
>  					g_object_ref_sink(gst_libcamera_device_new(camera)));
>  	}
>  
> -	cm->stop();
> -
>  	return devices;
>  }
>  
> @@ -204,31 +201,16 @@ gst_libcamera_provider_init(GstLibcameraProvider *self)
>  {
>  	GstDeviceProvider *provider = GST_DEVICE_PROVIDER(self);
>  
> -	self->cm = new CameraManager();
> -
>  	/* Avoid devices being duplicated. */
>  	gst_device_provider_hide_provider(provider, "v4l2deviceprovider");
>  }
>  
> -static void
> -gst_libcamera_provider_finalize(GObject *object)
> -{
> -	GstLibcameraProvider *self = GST_LIBCAMERA_PROVIDER(object);
> -	gpointer klass = gst_libcamera_provider_parent_class;
> -
> -	delete self->cm;
> -
> -	return G_OBJECT_CLASS(klass)->finalize(object);
> -}
> -
>  static void
>  gst_libcamera_provider_class_init(GstLibcameraProviderClass *klass)
>  {
>  	GstDeviceProviderClass *provider_class = GST_DEVICE_PROVIDER_CLASS(klass);
> -	GObjectClass *object_class = G_OBJECT_CLASS(klass);
>  
>  	provider_class->probe = gst_libcamera_provider_probe;
> -	object_class->finalize = gst_libcamera_provider_finalize;
>  
>  	gst_device_provider_class_set_metadata(provider_class,
>  					       "libcamera Device Provider",
> diff --git a/src/gstreamer/gstlibcamerasrc.cpp b/src/gstreamer/gstlibcamerasrc.cpp
> index 4c7b36ae..bdd9f88c 100644
> --- a/src/gstreamer/gstlibcamerasrc.cpp
> +++ b/src/gstreamer/gstlibcamerasrc.cpp
> @@ -104,7 +104,7 @@ GstBuffer *RequestWrap::detachBuffer(Stream *stream)
>  struct GstLibcameraSrcState {
>  	GstLibcameraSrc *src_;
>  
> -	std::unique_ptr<CameraManager> cm_;
> +	std::shared_ptr<CameraManager> cm_;
>  	std::shared_ptr<Camera> cam_;
>  	std::unique_ptr<CameraConfiguration> config_;
>  	std::vector<GstPad *> srcpads_;
> @@ -198,13 +198,13 @@ GstLibcameraSrcState::requestCompleted(Request *request)
>  static bool
>  gst_libcamera_src_open(GstLibcameraSrc *self)
>  {
> -	std::unique_ptr<CameraManager> cm = std::make_unique<CameraManager>();
> +	std::shared_ptr<CameraManager> cm;
>  	std::shared_ptr<Camera> cam;
> -	gint ret = 0;
> +	gint ret;
>  
>  	GST_DEBUG_OBJECT(self, "Opening camera device ...");
>  
> -	ret = cm->start();
> +	cm = gst_libcamera_get_camera_mananger(ret);
>  	if (ret) {
>  		GST_ELEMENT_ERROR(self, LIBRARY, INIT,
>  				  ("Failed listing cameras."),
> @@ -250,7 +250,7 @@ gst_libcamera_src_open(GstLibcameraSrc *self)
>  	cam->requestCompleted.connect(self->state, &GstLibcameraSrcState::requestCompleted);
>  
>  	/* No need to lock here, we didn't start our threads yet. */
> -	self->state->cm_ = std::move(cm);
> +	self->state->cm_ = cm;
>  	self->state->cam_ = cam;
>  
>  	return true;
> @@ -517,7 +517,6 @@ gst_libcamera_src_close(GstLibcameraSrc *self)
>  	}
>  
>  	state->cam_.reset();
> -	state->cm_->stop();
>  	state->cm_.reset();
>  }
>
Nicolas Dufresne Aug. 26, 2021, 1:21 p.m. UTC | #2 
Le jeudi 26 août 2021 à 02:18 +0300, Laurent Pinchart a écrit :
> Hi Nicolas,
> 
> Thank you for the patch.
> 
> On Wed, Aug 25, 2021 at 05:18:51PM -0400, Nicolas Dufresne wrote:
> > From: Nicolas Dufresne <nicolas.dufresne@collabora.com>
> > 
> > It's not allowed to have multiple instances of CameraManager. This
> > requirement is not easy for GStreamer were the device monitor and
> > the camerasrc, or two camerasrc instances don't usually have any
> > interaction between each other. This this by implementing a minimalist
> 
> s/This this/Fix this/ ?
> 
> > singleton around CameraManager constructor and start()/stop()
> > operations.
> > 
> > Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
> > ---
> >  src/gstreamer/gstlibcamera-utils.cpp   | 31 ++++++++++++++++++++++++++
> >  src/gstreamer/gstlibcamera-utils.h     |  6 +++--
> >  src/gstreamer/gstlibcameraprovider.cpp | 22 ++----------------
> >  src/gstreamer/gstlibcamerasrc.cpp      | 11 +++++----
> >  4 files changed, 42 insertions(+), 28 deletions(-)
> > 
> > diff --git a/src/gstreamer/gstlibcamera-utils.cpp b/src/gstreamer/gstlibcamera-utils.cpp
> > index 007d6a64..34b64c4a 100644
> > --- a/src/gstreamer/gstlibcamera-utils.cpp
> > +++ b/src/gstreamer/gstlibcamera-utils.cpp
> > @@ -221,3 +221,34 @@ gst_libcamera_resume_task(GstTask *task)
> >  		GST_TASK_SIGNAL(task);
> >  	}
> >  }
> > +
> > +G_LOCK_DEFINE_STATIC(cm_singleton_lock);
> > +std::weak_ptr<CameraManager> cm_singleton_ptr;
> > +
> > +void _cm_deleter(CameraManager *cm)
> > +{
> > +	g_print("Delete CameraManager\n");
> > +	cm->stop();
> > +	delete cm;
> 
> The CameraManager destructor calls stop(), so if you don't care much
> about the g_print(), you could drop this function.
> 
> > +}
> > +
> > +std::shared_ptr<CameraManager>
> > +gst_libcamera_get_camera_mananger(int &ret)
> > +{
> > +	std::shared_ptr<CameraManager> cm;
> > +
> > +	G_LOCK(cm_singleton_lock);
> > +
> > +	cm = cm_singleton_ptr.lock();
> > +	if (cm_singleton_ptr.expired()) {
> 
> I think you could write this
> 
> 	cm = cm_singleton_ptr.lock();
> 	if (cm) {

With "if (!cm)" that works.

> 
> as std::weak_ptr<>::lock() return a null std::shared_ptr<> if it has
> expired.
> 
> > +		std::shared_ptr<CameraManager> ptr(new CameraManager(), _cm_deleter);
> > +		cm_singleton_ptr = cm = ptr;
> 
> And there's no need for the local ptr variable here, you can write
> 
> 		cm = std::shared_ptr<CameraManager>(new CameraManager(), _cm_deleter);
> 		cm_singleton_ptr = cm;
> 
> If you don't care about the deleter, it could also become

I'll drop the deleter if I don't need to call stop() explicitly.

> 
> 		cm = std::make_shared<CameraManager>();
> 		cm_singleton_ptr = cm;
> 
> > +		ret = cm->start();
> > +	} else {
> > +		ret = 0;
> > +	}
> > +
> > +	G_UNLOCK(cm_singleton_lock);
> > +
> > +	return cm;
> > +}
> > diff --git a/src/gstreamer/gstlibcamera-utils.h b/src/gstreamer/gstlibcamera-utils.h
> > index 2b3f26b6..67a06db3 100644
> > --- a/src/gstreamer/gstlibcamera-utils.h
> > +++ b/src/gstreamer/gstlibcamera-utils.h
> > @@ -9,16 +9,18 @@
> >  #ifndef __GST_LIBCAMERA_UTILS_H__
> >  #define __GST_LIBCAMERA_UTILS_H__
> >  
> > +#include <libcamera/camera_manager.h>
> > +#include <libcamera/stream.h>
> > +
> >  #include <gst/gst.h>
> >  #include <gst/video/video.h>
> >  
> > -#include <libcamera/stream.h>
> > -
> >  GstCaps *gst_libcamera_stream_formats_to_caps(const libcamera::StreamFormats &formats);
> >  GstCaps *gst_libcamera_stream_configuration_to_caps(const libcamera::StreamConfiguration &stream_cfg);
> >  void gst_libcamera_configure_stream_from_caps(libcamera::StreamConfiguration &stream_cfg,
> >  					      GstCaps *caps);
> >  void gst_libcamera_resume_task(GstTask *task);
> > +std::shared_ptr<libcamera::CameraManager> gst_libcamera_get_camera_mananger(int &ret);
> >  
> >  /**
> >   * \class GLibLocker
> > diff --git a/src/gstreamer/gstlibcameraprovider.cpp b/src/gstreamer/gstlibcameraprovider.cpp
> > index 29da6c32..948ba0d1 100644
> > --- a/src/gstreamer/gstlibcameraprovider.cpp
> > +++ b/src/gstreamer/gstlibcameraprovider.cpp
> > @@ -158,7 +158,6 @@ gst_libcamera_device_new(const std::shared_ptr<Camera> &camera)
> >  
> >  struct _GstLibcameraProvider {
> >  	GstDeviceProvider parent;
> > -	CameraManager *cm;
> >  };
> 
> Is this constructed on demand to call probe() and then immediately
> destroyed that it makes no sense anymore to cache the pointer ?

Correct, this is a bit of an intermediate. In this temporary implementation
(non-monitoring). I was doing start() enum stop(), so that each time probe is
called the list was fresh. This is as close as I can get using a singleton here.
But consider this a temporary state.

To support the new API, we need a C++ class to hold the shared ptr (like
libcamersrc). I'll introduce this while adding monitoring support. This is just
to keep the the thing minimally working and small.

> 
> >  
> >  G_DEFINE_TYPE_WITH_CODE(GstLibcameraProvider, gst_libcamera_provider,
> > @@ -170,7 +169,7 @@ static GList *
> >  gst_libcamera_provider_probe(GstDeviceProvider *provider)
> >  {
> >  	GstLibcameraProvider *self = GST_LIBCAMERA_PROVIDER(provider);
> > -	CameraManager *cm = self->cm;
> > +	std::shared_ptr<CameraManager> cm;
> >  	GList *devices = nullptr;
> >  	gint ret;
> >  
> > @@ -181,7 +180,7 @@ gst_libcamera_provider_probe(GstDeviceProvider *provider)
> >  	 * gains monitoring support. Meanwhile we need to cycle start()/stop()
> >  	 * to ensure every probe() calls return the latest list.
> >  	 */
> > -	ret = cm->start();
> > +	cm = gst_libcamera_get_camera_mananger(ret);
> >  	if (ret) {
> >  		GST_ERROR_OBJECT(self, "Failed to retrieve device list: %s",
> >  				 g_strerror(-ret));
> > @@ -194,8 +193,6 @@ gst_libcamera_provider_probe(GstDeviceProvider *provider)
> >  					g_object_ref_sink(gst_libcamera_device_new(camera)));
> >  	}
> >  
> > -	cm->stop();
> > -
> >  	return devices;
> >  }
> >  
> > @@ -204,31 +201,16 @@ gst_libcamera_provider_init(GstLibcameraProvider *self)
> >  {
> >  	GstDeviceProvider *provider = GST_DEVICE_PROVIDER(self);
> >  
> > -	self->cm = new CameraManager();
> > -
> >  	/* Avoid devices being duplicated. */
> >  	gst_device_provider_hide_provider(provider, "v4l2deviceprovider");
> >  }
> >  
> > -static void
> > -gst_libcamera_provider_finalize(GObject *object)
> > -{
> > -	GstLibcameraProvider *self = GST_LIBCAMERA_PROVIDER(object);
> > -	gpointer klass = gst_libcamera_provider_parent_class;
> > -
> > -	delete self->cm;
> > -
> > -	return G_OBJECT_CLASS(klass)->finalize(object);
> > -}
> > -
> >  static void
> >  gst_libcamera_provider_class_init(GstLibcameraProviderClass *klass)
> >  {
> >  	GstDeviceProviderClass *provider_class = GST_DEVICE_PROVIDER_CLASS(klass);
> > -	GObjectClass *object_class = G_OBJECT_CLASS(klass);
> >  
> >  	provider_class->probe = gst_libcamera_provider_probe;
> > -	object_class->finalize = gst_libcamera_provider_finalize;
> >  
> >  	gst_device_provider_class_set_metadata(provider_class,
> >  					       "libcamera Device Provider",
> > diff --git a/src/gstreamer/gstlibcamerasrc.cpp b/src/gstreamer/gstlibcamerasrc.cpp
> > index 4c7b36ae..bdd9f88c 100644
> > --- a/src/gstreamer/gstlibcamerasrc.cpp
> > +++ b/src/gstreamer/gstlibcamerasrc.cpp
> > @@ -104,7 +104,7 @@ GstBuffer *RequestWrap::detachBuffer(Stream *stream)
> >  struct GstLibcameraSrcState {
> >  	GstLibcameraSrc *src_;
> >  
> > -	std::unique_ptr<CameraManager> cm_;
> > +	std::shared_ptr<CameraManager> cm_;
> >  	std::shared_ptr<Camera> cam_;
> >  	std::unique_ptr<CameraConfiguration> config_;
> >  	std::vector<GstPad *> srcpads_;
> > @@ -198,13 +198,13 @@ GstLibcameraSrcState::requestCompleted(Request *request)
> >  static bool
> >  gst_libcamera_src_open(GstLibcameraSrc *self)
> >  {
> > -	std::unique_ptr<CameraManager> cm = std::make_unique<CameraManager>();
> > +	std::shared_ptr<CameraManager> cm;
> >  	std::shared_ptr<Camera> cam;
> > -	gint ret = 0;
> > +	gint ret;
> >  
> >  	GST_DEBUG_OBJECT(self, "Opening camera device ...");
> >  
> > -	ret = cm->start();
> > +	cm = gst_libcamera_get_camera_mananger(ret);
> >  	if (ret) {
> >  		GST_ELEMENT_ERROR(self, LIBRARY, INIT,
> >  				  ("Failed listing cameras."),
> > @@ -250,7 +250,7 @@ gst_libcamera_src_open(GstLibcameraSrc *self)
> >  	cam->requestCompleted.connect(self->state, &GstLibcameraSrcState::requestCompleted);
> >  
> >  	/* No need to lock here, we didn't start our threads yet. */
> > -	self->state->cm_ = std::move(cm);
> > +	self->state->cm_ = cm;
> >  	self->state->cam_ = cam;
> >  
> >  	return true;
> > @@ -517,7 +517,6 @@ gst_libcamera_src_close(GstLibcameraSrc *self)
> >  	}
> >  
> >  	state->cam_.reset();
> > -	state->cm_->stop();
> >  	state->cm_.reset();
> >  }
> >  
>

Patch
diff mbox series 

diff --git a/src/gstreamer/gstlibcamera-utils.cpp b/src/gstreamer/gstlibcamera-utils.cpp
index 007d6a64..34b64c4a 100644
--- a/src/gstreamer/gstlibcamera-utils.cpp
+++ b/src/gstreamer/gstlibcamera-utils.cpp
@@ -221,3 +221,34 @@  gst_libcamera_resume_task(GstTask *task)
 		GST_TASK_SIGNAL(task);
 	}
 }
+
+G_LOCK_DEFINE_STATIC(cm_singleton_lock);
+std::weak_ptr<CameraManager> cm_singleton_ptr;
+
+void _cm_deleter(CameraManager *cm)
+{
+	g_print("Delete CameraManager\n");
+	cm->stop();
+	delete cm;
+}
+
+std::shared_ptr<CameraManager>
+gst_libcamera_get_camera_mananger(int &ret)
+{
+	std::shared_ptr<CameraManager> cm;
+
+	G_LOCK(cm_singleton_lock);
+
+	cm = cm_singleton_ptr.lock();
+	if (cm_singleton_ptr.expired()) {
+		std::shared_ptr<CameraManager> ptr(new CameraManager(), _cm_deleter);
+		cm_singleton_ptr = cm = ptr;
+		ret = cm->start();
+	} else {
+		ret = 0;
+	}
+
+	G_UNLOCK(cm_singleton_lock);
+
+	return cm;
+}
diff --git a/src/gstreamer/gstlibcamera-utils.h b/src/gstreamer/gstlibcamera-utils.h
index 2b3f26b6..67a06db3 100644
--- a/src/gstreamer/gstlibcamera-utils.h
+++ b/src/gstreamer/gstlibcamera-utils.h
@@ -9,16 +9,18 @@ 
 #ifndef __GST_LIBCAMERA_UTILS_H__
 #define __GST_LIBCAMERA_UTILS_H__
 
+#include <libcamera/camera_manager.h>
+#include <libcamera/stream.h>
+
 #include <gst/gst.h>
 #include <gst/video/video.h>
 
-#include <libcamera/stream.h>
-
 GstCaps *gst_libcamera_stream_formats_to_caps(const libcamera::StreamFormats &formats);
 GstCaps *gst_libcamera_stream_configuration_to_caps(const libcamera::StreamConfiguration &stream_cfg);
 void gst_libcamera_configure_stream_from_caps(libcamera::StreamConfiguration &stream_cfg,
 					      GstCaps *caps);
 void gst_libcamera_resume_task(GstTask *task);
+std::shared_ptr<libcamera::CameraManager> gst_libcamera_get_camera_mananger(int &ret);
 
 /**
  * \class GLibLocker
diff --git a/src/gstreamer/gstlibcameraprovider.cpp b/src/gstreamer/gstlibcameraprovider.cpp
index 29da6c32..948ba0d1 100644
--- a/src/gstreamer/gstlibcameraprovider.cpp
+++ b/src/gstreamer/gstlibcameraprovider.cpp
@@ -158,7 +158,6 @@  gst_libcamera_device_new(const std::shared_ptr<Camera> &camera)
 
 struct _GstLibcameraProvider {
 	GstDeviceProvider parent;
-	CameraManager *cm;
 };
 
 G_DEFINE_TYPE_WITH_CODE(GstLibcameraProvider, gst_libcamera_provider,
@@ -170,7 +169,7 @@  static GList *
 gst_libcamera_provider_probe(GstDeviceProvider *provider)
 {
 	GstLibcameraProvider *self = GST_LIBCAMERA_PROVIDER(provider);
-	CameraManager *cm = self->cm;
+	std::shared_ptr<CameraManager> cm;
 	GList *devices = nullptr;
 	gint ret;
 
@@ -181,7 +180,7 @@  gst_libcamera_provider_probe(GstDeviceProvider *provider)
 	 * gains monitoring support. Meanwhile we need to cycle start()/stop()
 	 * to ensure every probe() calls return the latest list.
 	 */
-	ret = cm->start();
+	cm = gst_libcamera_get_camera_mananger(ret);
 	if (ret) {
 		GST_ERROR_OBJECT(self, "Failed to retrieve device list: %s",
 				 g_strerror(-ret));
@@ -194,8 +193,6 @@  gst_libcamera_provider_probe(GstDeviceProvider *provider)
 					g_object_ref_sink(gst_libcamera_device_new(camera)));
 	}
 
-	cm->stop();
-
 	return devices;
 }
 
@@ -204,31 +201,16 @@  gst_libcamera_provider_init(GstLibcameraProvider *self)
 {
 	GstDeviceProvider *provider = GST_DEVICE_PROVIDER(self);
 
-	self->cm = new CameraManager();
-
 	/* Avoid devices being duplicated. */
 	gst_device_provider_hide_provider(provider, "v4l2deviceprovider");
 }
 
-static void
-gst_libcamera_provider_finalize(GObject *object)
-{
-	GstLibcameraProvider *self = GST_LIBCAMERA_PROVIDER(object);
-	gpointer klass = gst_libcamera_provider_parent_class;
-
-	delete self->cm;
-
-	return G_OBJECT_CLASS(klass)->finalize(object);
-}
-
 static void
 gst_libcamera_provider_class_init(GstLibcameraProviderClass *klass)
 {
 	GstDeviceProviderClass *provider_class = GST_DEVICE_PROVIDER_CLASS(klass);
-	GObjectClass *object_class = G_OBJECT_CLASS(klass);
 
 	provider_class->probe = gst_libcamera_provider_probe;
-	object_class->finalize = gst_libcamera_provider_finalize;
 
 	gst_device_provider_class_set_metadata(provider_class,
 					       "libcamera Device Provider",
diff --git a/src/gstreamer/gstlibcamerasrc.cpp b/src/gstreamer/gstlibcamerasrc.cpp
index 4c7b36ae..bdd9f88c 100644
--- a/src/gstreamer/gstlibcamerasrc.cpp
+++ b/src/gstreamer/gstlibcamerasrc.cpp
@@ -104,7 +104,7 @@  GstBuffer *RequestWrap::detachBuffer(Stream *stream)
 struct GstLibcameraSrcState {
 	GstLibcameraSrc *src_;
 
-	std::unique_ptr<CameraManager> cm_;
+	std::shared_ptr<CameraManager> cm_;
 	std::shared_ptr<Camera> cam_;
 	std::unique_ptr<CameraConfiguration> config_;
 	std::vector<GstPad *> srcpads_;
@@ -198,13 +198,13 @@  GstLibcameraSrcState::requestCompleted(Request *request)
 static bool
 gst_libcamera_src_open(GstLibcameraSrc *self)
 {
-	std::unique_ptr<CameraManager> cm = std::make_unique<CameraManager>();
+	std::shared_ptr<CameraManager> cm;
 	std::shared_ptr<Camera> cam;
-	gint ret = 0;
+	gint ret;
 
 	GST_DEBUG_OBJECT(self, "Opening camera device ...");
 
-	ret = cm->start();
+	cm = gst_libcamera_get_camera_mananger(ret);
 	if (ret) {
 		GST_ELEMENT_ERROR(self, LIBRARY, INIT,
 				  ("Failed listing cameras."),
@@ -250,7 +250,7 @@  gst_libcamera_src_open(GstLibcameraSrc *self)
 	cam->requestCompleted.connect(self->state, &GstLibcameraSrcState::requestCompleted);
 
 	/* No need to lock here, we didn't start our threads yet. */
-	self->state->cm_ = std::move(cm);
+	self->state->cm_ = cm;
 	self->state->cam_ = cam;
 
 	return true;
@@ -517,7 +517,6 @@  gst_libcamera_src_close(GstLibcameraSrc *self)
 	}
 
 	state->cam_.reset();
-	state->cm_->stop();
 	state->cm_.reset();
 }