Re: [PATCH] dmaengine: dmatest: timeout value of -1 should specify infinite wait

From: Vinod Koul
Date: Tue Jun 04 2019 - 08:31:00 EST


On 31-05-19, 19:43, Hook, Gary wrote:
> The dmatest module parameter 'timeout' is documented as accepting a
> -1 to mean "infinite timeout". Change the parameter to to signed
> integer, and check the value to call the appropriate wait_event()
> function.
>
> Signed-off-by: Gary R Hook <gary.hook@xxxxxxx>
> ---
> drivers/dma/dmatest.c | 11 ++++++++---
> 1 file changed, 8 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/dma/dmatest.c b/drivers/dma/dmatest.c
> index b96814a7dceb..28a237686578 100644
> --- a/drivers/dma/dmatest.c
> +++ b/drivers/dma/dmatest.c
> @@ -63,7 +63,7 @@ MODULE_PARM_DESC(pq_sources,
> "Number of p+q source buffers (default: 3)");
>
> static int timeout = 3000;
> -module_param(timeout, uint, S_IRUGO | S_IWUSR);
> +module_param(timeout, int, S_IRUGO | S_IWUSR);
> MODULE_PARM_DESC(timeout, "Transfer Timeout in msec (default: 3000), "
> "Pass -1 for infinite timeout");
>
> @@ -795,8 +795,13 @@ static int dmatest_func(void *data)
> }
> dma_async_issue_pending(chan);
>
> - wait_event_freezable_timeout(thread->done_wait, done->done,
> - msecs_to_jiffies(params->timeout));
> + /* A timeout value of -1 means infinite wait */
> + if (timeout == -1)
> + wait_event_freezable(thread->done_wait, done->done);

well i am not too happy that we have a infinite wait and no way to
cancel, maybe remove this case?

> + else
> + wait_event_freezable_timeout(thread->done_wait,
> + done->done,
> + msecs_to_jiffies(params->timeout));
>
> status = dma_async_is_tx_complete(chan, cookie, NULL, NULL);
>
>

--
~Vinod