Re: repeat a function after fixed time period

[Arjan van de Ven]

> 
> This kernel code should do just fine.
> 
> 
> 
> struct INFO {
>      struct timer_list timer;            // For test timer
>      atomic_t running;                   // Timer is running
>      };
> 
> //-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
> //
> //   This stops the timer. This must NOT be called with a spin-lock
> //   held.
> //
> static void stop_timer()
> {
>      if(atomic_read(&info->running))
>      {
>          atomic_dec(&info->running);

this is a race.

>          if(info->timer.function)
>              del_timer(&info->timer);

you probably want del_timer_sync() here.


> static void start_timer(void)
> {
>      if(!atomic_read(&info->running))
>      {
>          atomic_inc(&info->running);

same race.


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/