On 12 June 2018 at 10:22, Ezequiel Garcia <ezequiel@xxxxxxxxxxxxx> wrote:
> If there is a schedulable job, v4l2_m2m_try_schedule() calls
> v4l2_m2m_try_run(). This makes the unconditional v4l2_m2m_try_run()
> called by v4l2_m2m_job_finish superfluous. Remove it.
>
> Fixes: 7f98639def42 ("V4L/DVB: add memory-to-memory device helper framework for videobuf")
> Signed-off-by: Ezequiel Garcia <ezequiel@xxxxxxxxxxxxx>
> ---
> drivers/media/v4l2-core/v4l2-mem2mem.c | 1 -
> 1 file changed, 1 deletion(-)
>
> diff --git a/drivers/media/v4l2-core/v4l2-mem2mem.c b/drivers/media/v4l2-core/v4l2-mem2mem.c
> index c4f963d96a79..5f9cd5b74cda 100644
> --- a/drivers/media/v4l2-core/v4l2-mem2mem.c
> +++ b/drivers/media/v4l2-core/v4l2-mem2mem.c
> @@ -339,7 +339,6 @@ void v4l2_m2m_job_finish(struct v4l2_m2m_dev *m2m_dev,
> * allow more than one job on the job_queue per instance, each has
> * to be scheduled separately after the previous one finishes. */
> v4l2_m2m_try_schedule(m2m_ctx);
> - v4l2_m2m_try_run(m2m_dev);
> }
> EXPORT_SYMBOL(v4l2_m2m_job_finish);
>
Hi Mauro, Hans,
Please note that this patch (which is merged in Mauro's) introduces an issue
in the following scenario:
1) Context A schedules, queues and runs job A.
2) While the m2m device is running, context B schedules
and queues job B. Job B cannot run, because it has to
wait for job A.
3) Job A completes, calls v4l2_m2m_job_finish, and tries
to queue a job for context A, but since the context is
empty it won't do anything.
In this scenario, queued job B will never run.
The issue is fixed in https://patchwork.kernel.org/patch/10544487/
I don't know what's the best way to proceed here, pick the fix or simply
drop this commit instead?
--
Ezequiel García, VanguardiaSur
www.vanguardiasur.com.ar
