[linux-2.6-block.git] / block / blk-cgroup.h

#ifndef _BLK_CGROUP_H
#define _BLK_CGROUP_H
/*
 * Common Block IO controller cgroup interface
 *
 * Based on ideas and code from CFQ, CFS and BFQ:
 * Copyright (C) 2003 Jens Axboe <axboe@kernel.dk>
 *
 * Copyright (C) 2008 Fabio Checconi <fabio@gandalf.sssup.it>
 *		      Paolo Valente <paolo.valente@unimore.it>
 *
 * Copyright (C) 2009 Vivek Goyal <vgoyal@redhat.com>
 * 	              Nauman Rafique <nauman@google.com>
 */

#include <linux/cgroup.h>

#ifdef CONFIG_BLK_CGROUP

struct blkio_cgroup {
	struct cgroup_subsys_state css;
	unsigned int weight;
	spinlock_t lock;
	struct hlist_head blkg_list;
};

struct blkio_group {
	/* An rcu protected unique identifier for the group */
	void *key;
	struct hlist_node blkcg_node;
	unsigned short blkcg_id;
#ifdef CONFIG_DEBUG_BLK_CGROUP
	/* Store cgroup path */
	char path[128];
	/* How many times this group has been removed from service tree */
	unsigned long dequeue;
#endif
	/* The device MKDEV(major, minor), this group has been created for */
	dev_t   dev;

	/* total disk time and nr sectors dispatched by this group */
	unsigned long time;
	unsigned long sectors;
};

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
#define BLKIO_WEIGHT_MAX	1000
#define BLKIO_WEIGHT_DEFAULT	500

#ifdef CONFIG_DEBUG_BLK_CGROUP
static inline char *blkg_path(struct blkio_group *blkg)
{
	return blkg->path;
}
void blkiocg_update_blkio_group_dequeue_stats(struct blkio_group *blkg,
				unsigned long dequeue);
#else
static inline char *blkg_path(struct blkio_group *blkg) { return NULL; }
static inline void blkiocg_update_blkio_group_dequeue_stats(
			struct blkio_group *blkg, unsigned long dequeue) {}
#endif

#ifdef CONFIG_BLK_CGROUP
extern struct blkio_cgroup blkio_root_cgroup;
extern struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup);
extern void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
			struct blkio_group *blkg, void *key, dev_t dev);
extern int blkiocg_del_blkio_group(struct blkio_group *blkg);
extern struct blkio_group *blkiocg_lookup_group(struct blkio_cgroup *blkcg,
						void *key);
void blkiocg_update_blkio_group_stats(struct blkio_group *blkg,
			unsigned long time, unsigned long sectors);
#else
struct cgroup;
static inline struct blkio_cgroup *
cgroup_to_blkio_cgroup(struct cgroup *cgroup) { return NULL; }

static inline void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
			struct blkio_group *blkg, void *key, dev_t dev)
{
}

static inline int
blkiocg_del_blkio_group(struct blkio_group *blkg) { return 0; }

static inline struct blkio_group *
blkiocg_lookup_group(struct blkio_cgroup *blkcg, void *key) { return NULL; }
static inline void blkiocg_update_blkio_group_stats(struct blkio_group *blkg,
			unsigned long time, unsigned long sectors)
{
}
#endif
#endif /* _BLK_CGROUP_H */
Commit	Line	Data
31e4c28d VG	1	#ifndef _BLK_CGROUP_H
	2	#define _BLK_CGROUP_H
	3	/*
	4	* Common Block IO controller cgroup interface
	5	*
	6	* Based on ideas and code from CFQ, CFS and BFQ:
	7	* Copyright (C) 2003 Jens Axboe <axboe@kernel.dk>
	8	*
	9	* Copyright (C) 2008 Fabio Checconi <fabio@gandalf.sssup.it>
	10	* Paolo Valente <paolo.valente@unimore.it>
	11	*
	12	* Copyright (C) 2009 Vivek Goyal <vgoyal@redhat.com>
	13	* Nauman Rafique <nauman@google.com>
	14	*/
	15
	16	#include <linux/cgroup.h>
	17
2f5ea477 JA	18	#ifdef CONFIG_BLK_CGROUP
2f5ea477 JA	19
31e4c28d VG	20	struct blkio_cgroup {
	21	struct cgroup_subsys_state css;
	22	unsigned int weight;
	23	spinlock_t lock;
	24	struct hlist_head blkg_list;
	25	};
	26
	27	struct blkio_group {
	28	/* An rcu protected unique identifier for the group */
	29	void *key;
	30	struct hlist_node blkcg_node;
b1c35769	31	unsigned short blkcg_id;
2868ef7b VG	32	#ifdef CONFIG_DEBUG_BLK_CGROUP
	33	/* Store cgroup path */
	34	char path[128];
22084190 VG	35	/* How many times this group has been removed from service tree */
22084190 VG	36	unsigned long dequeue;
2868ef7b	37	#endif
22084190 VG	38	/* The device MKDEV(major, minor), this group has been created for */
	39	dev_t dev;
	40
	41	/* total disk time and nr sectors dispatched by this group */
	42	unsigned long time;
	43	unsigned long sectors;
31e4c28d VG	44	};
31e4c28d VG	45
9d6a986c VG	46	extern bool blkiocg_css_tryget(struct blkio_cgroup *blkcg);
	47	extern void blkiocg_css_put(struct blkio_cgroup *blkcg);
	48
3e252066 VG	49	typedef void (blkio_unlink_group_fn) (void key, struct blkio_group blkg);
	50	typedef void (blkio_update_group_weight_fn) (struct blkio_group *blkg,
	51	unsigned int weight);
	52
	53	struct blkio_policy_ops {
	54	blkio_unlink_group_fn *blkio_unlink_group_fn;
	55	blkio_update_group_weight_fn *blkio_update_group_weight_fn;
	56	};
	57
	58	struct blkio_policy_type {
	59	struct list_head list;
	60	struct blkio_policy_ops ops;
	61	};
	62
	63	/* Blkio controller policy registration */
	64	extern void blkio_policy_register(struct blkio_policy_type *);
	65	extern void blkio_policy_unregister(struct blkio_policy_type *);
	66
2f5ea477 JA	67	#else
	68
	69	struct blkio_group {
	70	};
	71
3e252066 VG	72	struct blkio_policy_type {
	73	};
	74
	75	static inline void blkio_policy_register(struct blkio_policy_type *blkiop) { }
	76	static inline void blkio_policy_unregister(struct blkio_policy_type *blkiop) { }
	77
2f5ea477 JA	78	#endif
2f5ea477 JA	79
31e4c28d VG	80	#define BLKIO_WEIGHT_MIN 100
	81	#define BLKIO_WEIGHT_MAX 1000
	82	#define BLKIO_WEIGHT_DEFAULT 500
	83
2868ef7b VG	84	#ifdef CONFIG_DEBUG_BLK_CGROUP
	85	static inline char blkg_path(struct blkio_group blkg)
	86	{
	87	return blkg->path;
	88	}
22084190 VG	89	void blkiocg_update_blkio_group_dequeue_stats(struct blkio_group *blkg,
22084190 VG	90	unsigned long dequeue);
2868ef7b VG	91	#else
2868ef7b VG	92	static inline char blkg_path(struct blkio_group blkg) { return NULL; }
22084190 VG	93	static inline void blkiocg_update_blkio_group_dequeue_stats(
22084190 VG	94	struct blkio_group *blkg, unsigned long dequeue) {}
2868ef7b VG	95	#endif
2868ef7b VG	96
31e4c28d VG	97	#ifdef CONFIG_BLK_CGROUP
	98	extern struct blkio_cgroup blkio_root_cgroup;
	99	extern struct blkio_cgroup cgroup_to_blkio_cgroup(struct cgroup cgroup);
	100	extern void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
22084190	101	struct blkio_group blkg, void key, dev_t dev);
31e4c28d VG	102	extern int blkiocg_del_blkio_group(struct blkio_group *blkg);
	103	extern struct blkio_group blkiocg_lookup_group(struct blkio_cgroup blkcg,
	104	void *key);
22084190 VG	105	void blkiocg_update_blkio_group_stats(struct blkio_group *blkg,
22084190 VG	106	unsigned long time, unsigned long sectors);
31e4c28d	107	#else
2f5ea477	108	struct cgroup;
31e4c28d VG	109	static inline struct blkio_cgroup *
	110	cgroup_to_blkio_cgroup(struct cgroup *cgroup) { return NULL; }
	111
	112	static inline void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
22084190	113	struct blkio_group blkg, void key, dev_t dev)
31e4c28d VG	114	{
	115	}
	116
	117	static inline int
	118	blkiocg_del_blkio_group(struct blkio_group *blkg) { return 0; }
	119
	120	static inline struct blkio_group *
	121	blkiocg_lookup_group(struct blkio_cgroup blkcg, void key) { return NULL; }
22084190 VG	122	static inline void blkiocg_update_blkio_group_stats(struct blkio_group *blkg,
	123	unsigned long time, unsigned long sectors)
	124	{
	125	}
31e4c28d VG	126	#endif
31e4c28d VG	127	#endif /* _BLK_CGROUP_H */