cc'ing Doug as he might be really interested on this patch
On 1/8/19 13:13, Peter Zijlstra wrote:
> The SPI thingies request FIFO-99 by default, reduce this to FIFO-50.
>
You say below that is not a suitable default but there is any other reason? Did
you observed problems with this?
> FIFO-99 is the very highest priority available to SCHED_FIFO and
> it not a suitable default; it would indicate the SPI work is the
> most important work on the machine.
>
> Cc: Benson Leung <ble...@chromium.org>
> Cc: Enric Balletbo i Serra <enric.balle...@collabora.com>
> Cc: Guenter Roeck <gro...@chromium.org>
> Cc: Mark Brown <broo...@kernel.org>
> Cc: linux-...@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org>
> ---
> drivers/platform/chrome/cros_ec_spi.c | 2 +-
> drivers/spi/spi.c | 2 +-
> 2 files changed, 2 insertions(+), 2 deletions(-)
>
> --- a/drivers/platform/chrome/cros_ec_spi.c
> +++ b/drivers/platform/chrome/cros_ec_spi.c
> @@ -706,7 +706,7 @@ static int cros_ec_spi_devm_high_pri_all
> struct cros_ec_spi *ec_spi)
> {
> struct sched_param sched_priority = {
> - .sched_priority = MAX_RT_PRIO - 1,
> + .sched_priority = MAX_RT_PRIO / 2,
> };
> int err;
>
> --- a/drivers/spi/spi.c
> +++ b/drivers/spi/spi.c
> @@ -1434,7 +1434,7 @@ static void spi_pump_messages(struct kth
> */
> static void spi_set_thread_rt(struct spi_controller *ctlr)
> {
> - struct sched_param param = { .sched_priority = MAX_RT_PRIO - 1 };
> + struct sched_param param = { .sched_priority = MAX_RT_PRIO / 2 };
>
> dev_info(&ctlr->dev,
> "will run message pump with realtime priority\n");
>
>
