On 28-04-20, 14:35, Andy Shevchenko wrote:
> If we do
>
> % echo 1 > /sys/module/dmatest/parameters/run
> [ 115.851124] dmatest: Could not start test, no channels configured
>
> % echo dma8chan7 > /sys/module/dmatest/parameters/channel
> [ 127.563872] dmatest: Added 1 threads using dma8chan7
>
> % cat /sys/module/dmatest/parameters/wait
> ... !!! HANG !!! ...
>
> The culprit is the commit 6138f967bccc
>
> ("dmaengine: dmatest: Use fixed point div to calculate iops")
>
> which makes threads not to run, but pending and being kicked off by writing
> to the 'run' node. However, it forgot to consider 'wait' routine to avoid
> above mentioned case.
>
> In order to fix this, check for really running threads, i.e. with pending
> and done flags unset.
>
> It's pity the culprit commit hadn't updated documentation and tested all
> possible scenarios.
Applied, thanks
--
~Vinod
