Re: [PATCH 1/2] c/r: Add CR_COPY() macro

["Serge E. Hallyn" <serue-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org>]

Quoting Dan Smith (danms-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org):
> As suggested by Dave, this provides us a way to make the copy-in and
> copy-out processes symmetric.  I also added CR_COPY_BIT() to use with
> the s390 bitfields, since we can't memcpy() those.
> 
> Signed-off-by: Dan Smith <danms-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org>
> ---
>  include/linux/checkpoint.h |   20 ++++++++++++++++++++
>  1 files changed, 20 insertions(+), 0 deletions(-)
> 
> diff --git a/include/linux/checkpoint.h b/include/linux/checkpoint.h
> index 217cf6e..b94422a 100644
> --- a/include/linux/checkpoint.h
> +++ b/include/linux/checkpoint.h
> @@ -149,4 +149,24 @@ static inline void process_deny_checkpointing(struct task_struct *task) {}
> 
>  #endif
> 
> +#define CR_CPT 1
> +#define CR_RST 2
> +
> +#define CR_COPY(op, a, b)				\
> +	do {						\
> +		WARN_ON(sizeof(a) != sizeof(b));	\

Can this be a BUILD_BUG_ON()?

> +		if (op == CR_CPT)			\
> +			memcpy(&a, &b, sizeof(a));	\
> +		else					\
> +			memcpy(&b, &a, sizeof(a));	\
> +	} while (0);
> +
> +#define CR_COPY_BIT(op, a, b)				\
> +	do {						\

maybe add a 
	BUILD_BUG_ON(typeof(a)!=typeof(b));
?

> +		if (op == CR_CPT)			\
> +			a = b;				\
> +		else					\
> +			b = a;				\
> +	} while (0);
> +
>  #endif /* _CHECKPOINT_CKPT_H_ */
> -- 
> 1.6.1
> 
> _______________________________________________
> Containers mailing list
> Containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org
> https://lists.linux-foundation.org/mailman/listinfo/containers