blkio: Implement dynamic io controlling policy registration

o One of the goals of block IO controller is that it should be able to
  support mulitple io control policies, some of which be operational at
  higher level in storage hierarchy.

o To begin with, we had one io controlling policy implemented by CFQ, and
  I hard coded the CFQ functions called by blkio. This created issues when
  CFQ is compiled as module.

o This patch implements a basic dynamic io controlling policy registration
  functionality in blkio. This is similar to elevator functionality where
  ioschedulers register the functions dynamically.

o Now in future, when more IO controlling policies are implemented, these
  can dynakically register with block IO controller.

Signed-off-by: Vivek Goyal <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
This commit is contained in:
Vivek Goyal 2009-12-04 10:36:42 -05:00 • committed by Jens Axboe
commit 3e25206689
4 changed files with 69 additions and 12 deletions

View file

@ -46,11 +46,35 @@ struct blkio_group {
extern bool blkiocg_css_tryget(struct blkio_cgroup *blkcg);
extern void blkiocg_css_put(struct blkio_cgroup *blkcg);
typedef void (blkio_unlink_group_fn) (void *key, struct blkio_group *blkg);
typedef void (blkio_update_group_weight_fn) (struct blkio_group *blkg,
unsigned int weight);
struct blkio_policy_ops {
blkio_unlink_group_fn *blkio_unlink_group_fn;
blkio_update_group_weight_fn *blkio_update_group_weight_fn;
};
struct blkio_policy_type {
struct list_head list;
struct blkio_policy_ops ops;
};
/* Blkio controller policy registration */
extern void blkio_policy_register(struct blkio_policy_type *);
extern void blkio_policy_unregister(struct blkio_policy_type *);
#else
struct blkio_group {
};
struct blkio_policy_type {
};
static inline void blkio_policy_register(struct blkio_policy_type *blkiop) { }
static inline void blkio_policy_unregister(struct blkio_policy_type *blkiop) { }
#endif
#define BLKIO_WEIGHT_MIN 100