[libcamera-devel] [PATCH 2/2] test: fence: Signal fence once

[Laurent Pinchart]

Hi Jacopo,

Thank you for the patch.

On Mon, Dec 13, 2021 at 03:51:43PM +0100, Jacopo Mondi wrote:
> The unit test associates a fence with a framebuffer and makes sure
> the fence is correctly signalled.
> 
> Once a fence is correctly signalled, it is released by the core, and the
> underlying file descriptor closed.
> 
> The unit test however tries to write on the fence file descriptor every
> time the designated Request is queued, and error which is now visible

s/and/an/

> as the return value of the fence signalling write() is checked.
> 
> Fix that by associating a fence with a framebuffer only once.
> 
> Signed-off-by: Jacopo Mondi <jacopo at jmondi.org>
> ---
>  test/fence.cpp | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/test/fence.cpp b/test/fence.cpp
> index d2865398784e..524db2a10757 100644
> --- a/test/fence.cpp
> +++ b/test/fence.cpp
> @@ -56,6 +56,7 @@ private:
>  	Stream *stream_;
>  
>  	bool expectedCompletionResult_ = true;
> +	bool setFence_ = true;
>  
>  	unsigned int completedRequest_;
>  
> @@ -193,7 +194,7 @@ void FenceTest::requestRequeue(Request *request)
>  
>  	request->reuse();
>  
> -	if (cookie == signalledRequestId_) {
> +	if (cookie == signalledRequestId_ && setFence_) {
>  		/*
>  		 * The second time this request is queued add a fence to it.
>  		 *
> @@ -257,6 +258,7 @@ void FenceTest::signalFence()
>  	if (ret != sizeof(value))
>  		cerr << "Failed to signal fence" << endl;
>  
> +	setFence_ = false;
>  	dispatcher_->processEvents();
>  }
>  
> @@ -316,7 +318,7 @@ int FenceTest::run()
>  	Timer timer;
>  	timer.start(1000);
>  	while (timer.isRunning() && expectedCompletionResult_) {
> -		if (completedRequest_ == signalledRequestId_)
> +		if (completedRequest_ == signalledRequestId_ && setFence_)

A bit of a hack, but I suppose it works. The test is hard to read,
there's room for improvement (and possibly a race condition or two), but
that's not urgent.

Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
Tested-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>

>  			/*
>  			 * signalledRequestId_ has just completed and it has
>  			 * been re-queued with a fence. Start the timer to

-- 
Regards,

Laurent Pinchart