Re: [PATCH v3 4/6] sched/completion: Add wait_for_completion_state()

[Rafael J. Wysocki]

On Mon, Aug 22, 2022 at 1:48 PM Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
>
> Allows waiting with a custom @state.
>
> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
> ---
>  include/linux/completion.h |    1 +
>  kernel/sched/completion.c  |    9 +++++++++
>  2 files changed, 10 insertions(+)
>
> --- a/include/linux/completion.h
> +++ b/include/linux/completion.h
> @@ -103,6 +103,7 @@ extern void wait_for_completion(struct c
>  extern void wait_for_completion_io(struct completion *);
>  extern int wait_for_completion_interruptible(struct completion *x);
>  extern int wait_for_completion_killable(struct completion *x);
> +extern int wait_for_completion_state(struct completion *x, unsigned int state);
>  extern unsigned long wait_for_completion_timeout(struct completion *x,
>                                                    unsigned long timeout);
>  extern unsigned long wait_for_completion_io_timeout(struct completion *x,
> --- a/kernel/sched/completion.c
> +++ b/kernel/sched/completion.c
> @@ -247,6 +247,15 @@ int __sched wait_for_completion_killable
>  }
>  EXPORT_SYMBOL(wait_for_completion_killable);
>
> +int __sched wait_for_completion_state(struct completion *x, unsigned int state)
> +{
> +       long t = wait_for_common(x, MAX_SCHEDULE_TIMEOUT, state);
> +       if (t == -ERESTARTSYS)
> +               return t;
> +       return 0;
> +}
> +EXPORT_SYMBOL(wait_for_completion_state);

Why not EXPORT_SYMBOL_GPL?  I guess to match the above?

> +
>  /**
>   * wait_for_completion_killable_timeout: - waits for completion of a task (w/(to,killable))
>   * @x:  holds the state of this particular completion
>
>