Re: [PATCH] [5/6] kfifo: Add kfifo_initialized

[Stefani Seibold <stefani@seibold.net>]

Am Sonntag, den 27.12.2009, 22:03 +0100 schrieb Andi Kleen:
> Simple inline that checks if kfifo_init() has been executed
> on a fifo.
> 
> This is useful for walking all per CPU fifos, when some of them
> might not have been brought up yet.
> 

Could be useful, i can implement it. But with the new macro based kfifo
there are also real in place fifo's, where the buffer is a part of the
kfifo structure. But in this case i can return always true.

Stefani

> Signed-off-by: Andi Kleen <ak@linux.intel.com>
> 
> ---
>  include/linux/kfifo.h |   10 ++++++++++
>  1 file changed, 10 insertions(+)
> 
> Index: linux/include/linux/kfifo.h
> ===================================================================
> --- linux.orig/include/linux/kfifo.h
> +++ linux/include/linux/kfifo.h
> @@ -117,6 +117,16 @@ extern __must_check unsigned int kfifo_o
>  extern __must_check unsigned int kfifo_out_peek(struct kfifo *fifo,
>  				void *to, unsigned int len, unsigned offset);
>  
> +/**
> + * kfifo_initialized - Check if kfifo is initialized.
> + * @fifo: fifo to check
> + * Return %true if FIFO is initialized, otherwise %false.
> + * Assumes the fifo was 0 before.
> + */
> +static inline bool kfifo_initialized(struct kfifo *fifo)
> +{
> +	return fifo->buffer != 0;
> +}
>  
>  /**
>   * kfifo_reset - removes the entire FIFO contents