Re: [PATCH 1/6] sctp multistream scheduling: declare sctp_sched_ops

[Vlad Yasevich <vladislav.yasevich@hp.com>]

Yaogong Wang wrote:
> Declare sctp_sched_ops structure and related functions
> 
> Signed-off-by: Yaogong Wang <ywang15@ncsu.edu>
> ---
> diff -uprN -X linux-2.6.32.8/Documentation/dontdiff
> linux-2.6.32.8/include/net/sctp/structs.h
> p1/include/net/sctp/structs.h
> --- linux-2.6.32.8/include/net/sctp/structs.h	2010-02-09
> 04:57:19.000000000 -0800
> +++ p1/include/net/sctp/structs.h	2010-05-28 10:33:12.000000000 -0700
> @@ -320,6 +320,9 @@ struct sctp_sock {
>  	/* Flags controlling Heartbeat, SACK delay, and Path MTU Discovery. */
>  	__u32 param_flags;
> 
> +	/* Multistream scheduling  */
> +	const struct sctp_sched_ops *sched_ops;
> +
>  	struct sctp_initmsg initmsg;
>  	struct sctp_rtoinfo rtoinfo;
>  	struct sctp_paddrparams paddrparam;
> @@ -534,6 +537,36 @@ static inline void sctp_ssn_skip(struct
>  }
> 
>  /*
> + * Interface for adding new SCTP scheduling handlers
> + * This is similar to the pluggable TCP congestion control
> + */
> +struct sctp_sched_ops {
> +	struct list_head	list;
> +
> +	/* initialize out_chunk_list (required) */
> +	int (*init)(struct sctp_outq *q, gfp_t gfp);
> +	/* cleanup out_chunk_list (required) */
> +	void (*release)(struct sctp_outq *q);
> +	/* enqueue head function (required) */
> +	void (*enqueue_head_data)(struct sctp_outq *q, struct sctp_chunk *ch);
> +	/* enqueue tail function (required) */
> +	void (*enqueue_tail_data)(struct sctp_outq *q, struct sctp_chunk *ch);
> +	/* dequeue function (required) */
> +	struct sctp_chunk* (*dequeue_data)(struct sctp_outq *q);
> +	/* is out_chunk_list empty? (required) */
> +	int (*is_empty)(struct sctp_outq *q);
> +
> +	char 		name[SCTP_SCHED_NAME_MAX];
> +	struct module 	*owner;
> +};
> +
> +extern int sctp_register_sched(struct sctp_sched_ops *type);
> +extern void sctp_unregister_sched(struct sctp_sched_ops *type);
> +
> +extern void sctp_cleanup_sched(struct sock *sk);
> +extern int sctp_set_sched(struct sock *sk, const char *name);
> +
> +/*
>   * Pointers to address related SCTP functions.
>   * (i.e. things that depend on the address family.)
>   */
> @@ -1650,6 +1683,9 @@ struct sctp_association {
>  	/* The largest timeout or RTO value to use in attempting an INIT */
>  	unsigned long max_init_timeo;
> 
> +	/* Multistream scheduling  */
> +	const struct sctp_sched_ops *sched_ops;
> +
>  	/* Heartbeat interval: The endpoint sends out a Heartbeat chunk to
>  	 * the destination address every heartbeat interval. This value
>  	 * will be inherited by all new transports.
> diff -uprN -X linux-2.6.32.8/Documentation/dontdiff
> linux-2.6.32.8/include/net/sctp/user.h p1/include/net/sctp/user.h
> --- linux-2.6.32.8/include/net/sctp/user.h	2010-02-09 04:57:19.000000000 -0800
> +++ p1/include/net/sctp/user.h	2010-05-28 10:52:57.000000000 -0700
> @@ -171,6 +171,8 @@ struct sctp_initmsg {
>  	__u16 sinit_max_init_timeo;
>  };
> 
> +#define SCTP_SCHED_NAME_MAX	16
> +
>  /*
>   * 5.2.2 SCTP Header Information Structure (SCTP_SNDRCV)
>   *
> 

You might as well through the global definition here as well.  You can set it
later, but let's define that in one place.

-vlad