Re: [rfc][patch] x86-64 new smp_call_function design

[Ingo Molnar <mingo@elte.hu>]

* Nick Piggin <npiggin@suse.de> wrote:

> This isn't finished yet, however I'd just like to ask for comments.

looks really interesting!

only one fundamental observation:

> +struct call_data {
> +	spinlock_t lock;
> +	struct list_head list;
>  	void (*func) (void *info);
>  	void *info;
> +	unsigned int flags;
> +	unsigned int refs;
> +	cpumask_t cpumask;
> +	struct rcu_head rcu_head;
>  };

> +struct call_single_data {
> +	struct list_head list;
> +	void (*func) (void *info);
> +	void *info;
> +	unsigned int flags;
> +};

the two structures are quite similar in size and role - why not have a 
type field and handle them largely together? I think we should try to 
preserve a single queue and a single vector - that would remove a number 
of ugly special-cases from the patch.

	Ingo