Re: [PATCH v3] tty: serial: qcom_geni_serial: Fix softlock

From: Doug Anderson
Date: Thu Nov 29 2018 - 21:22:58 EST


Hi,

On Thu, Nov 29, 2018 at 6:19 PM Ryan Case <ryandcase@xxxxxxxxxxxx> wrote:
>
> Transfers were being divided into device FIFO sized (64 byte max)
> operations which would poll for completion within a spin_lock_irqsave /
> spin_unlock_irqrestore block. This both made things slow by waiting for
> the FIFO to completely drain before adding further data and would also
> result in softlocks on large transmissions.
>
> This patch allows larger transfers with continuous FIFO additions as
> space becomes available and removes polling from the interrupt handler.
>
> Signed-off-by: Ryan Case <ryandcase@xxxxxxxxxxxx>
> ---
>
> Changes in v3:
> - Reworded comment for clarity
> - Fixed mips compiler warning
>
> Changes in v2:
> - Addressed nits raised by Stephen
>
> drivers/tty/serial/qcom_geni_serial.c | 56 +++++++++++++++++++--------
> 1 file changed, 39 insertions(+), 17 deletions(-)

Looks happy to me now. Thanks and sorry for misunderstanding how
"active" worked on v2.

Reviewed-by: Douglas Anderson <dianders@xxxxxxxxxxxx>