Re: [PATCH 1/2] watchdog: use __watchdog_ping in startup

[Guenter Roeck]

On Wed, Jun 24, 2020 at 02:45:33PM +0300, Tero Kristo wrote:
> Current watchdog startup functionality does not respect the minimum hw
> heartbeat setup and the last watchdog ping timeframe when watchdog is
> already running and userspace process attaches to it. Fix this by using
> the __watchdog_ping from the startup also. For this code path, we can
> also let the __watchdog_ping handle the bookkeeping for the worker and
> last keepalive times.
> 
> Signed-off-by: Tero Kristo <t-kristo@xxxxxx>

Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>

> ---
>  drivers/watchdog/watchdog_dev.c | 19 +++++++++++--------
>  1 file changed, 11 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c
> index 7e4cd34a8c20..bc1cfa288553 100644
> --- a/drivers/watchdog/watchdog_dev.c
> +++ b/drivers/watchdog/watchdog_dev.c
> @@ -275,15 +275,18 @@ static int watchdog_start(struct watchdog_device *wdd)
>  	set_bit(_WDOG_KEEPALIVE, &wd_data->status);
>  
>  	started_at = ktime_get();
> -	if (watchdog_hw_running(wdd) && wdd->ops->ping)
> -		err = wdd->ops->ping(wdd);
> -	else
> +	if (watchdog_hw_running(wdd) && wdd->ops->ping) {
> +		err = __watchdog_ping(wdd);
> +		if (err == 0)
> +			set_bit(WDOG_ACTIVE, &wdd->status);
> +	} else {
>  		err = wdd->ops->start(wdd);
> -	if (err == 0) {
> -		set_bit(WDOG_ACTIVE, &wdd->status);
> -		wd_data->last_keepalive = started_at;
> -		wd_data->last_hw_keepalive = started_at;
> -		watchdog_update_worker(wdd);
> +		if (err == 0) {
> +			set_bit(WDOG_ACTIVE, &wdd->status);
> +			wd_data->last_keepalive = started_at;
> +			wd_data->last_hw_keepalive = started_at;
> +			watchdog_update_worker(wdd);
> +		}
>  	}
>  
>  	return err;