[net-next-2.6.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>

#if defined(CONFIG_BLK_CGROUP) || defined(CONFIG_BLK_CGROUP_MODULE)

#ifndef CONFIG_BLK_CGROUP
/* When blk-cgroup is a module, its subsys_id isn't a compile-time constant */
extern struct cgroup_subsys blkio_subsys;
#define blkio_subsys_id blkio_subsys.subsys_id
#endif

enum stat_type {
	/* Total time spent (in ns) between request dispatch to the driver and
	 * request completion for IOs doen by this cgroup. This may not be
	 * accurate when NCQ is turned on. */
	BLKIO_STAT_SERVICE_TIME = 0,
	/* Total bytes transferred */
	BLKIO_STAT_SERVICE_BYTES,
	/* Total IOs serviced, post merge */
	BLKIO_STAT_SERVICED,
	/* Total time spent waiting in scheduler queue in ns */
	BLKIO_STAT_WAIT_TIME,
	/* All the single valued stats go below this */
	BLKIO_STAT_TIME,
	BLKIO_STAT_SECTORS,
#ifdef CONFIG_DEBUG_BLK_CGROUP
	BLKIO_STAT_DEQUEUE
#endif
};

enum stat_sub_type {
	BLKIO_STAT_READ = 0,
	BLKIO_STAT_WRITE,
	BLKIO_STAT_SYNC,
	BLKIO_STAT_ASYNC,
	BLKIO_STAT_TOTAL
};

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

struct blkio_group_stats {
	/* total disk time and nr sectors dispatched by this group */
	uint64_t time;
	uint64_t sectors;
	uint64_t stat_arr[BLKIO_STAT_WAIT_TIME + 1][BLKIO_STAT_TOTAL];
#ifdef CONFIG_DEBUG_BLK_CGROUP
	/* How many times this group has been removed from service tree */
	unsigned long dequeue;
#endif
};

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];
#endif
	/* The device MKDEV(major, minor), this group has been created for */
	dev_t dev;

	/* Need to serialize the stats in the case of reset/update */
	spinlock_t stats_lock;
	struct blkio_group_stats stats;
};

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_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_dequeue_stats(struct blkio_group *blkg,
						unsigned long dequeue) {}
#endif

#if defined(CONFIG_BLK_CGROUP) || defined(CONFIG_BLK_CGROUP_MODULE)
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 blkio_group_init(struct blkio_group *blkg);
void blkiocg_update_timeslice_used(struct blkio_group *blkg,
					unsigned long time);
void blkiocg_update_dispatch_stats(struct blkio_group *blkg, uint64_t bytes,
						bool direction, bool sync);
void blkiocg_update_completion_stats(struct blkio_group *blkg,
	uint64_t start_time, uint64_t io_start_time, bool direction, bool sync);
#else
struct cgroup;
static inline struct blkio_cgroup *
cgroup_to_blkio_cgroup(struct cgroup *cgroup) { return NULL; }

static inline void blkio_group_init(struct blkio_group *blkg) {}
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_timeslice_used(struct blkio_group *blkg,
						unsigned long time) {}
static inline void blkiocg_update_dispatch_stats(struct blkio_group *blkg,
				uint64_t bytes, bool direction, bool sync) {}
static inline void blkiocg_update_completion_stats(struct blkio_group *blkg,
		uint64_t start_time, uint64_t io_start_time, bool direction,
		bool sync) {}
#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
67523c48 BB	18	#if defined(CONFIG_BLK_CGROUP) \|\| defined(CONFIG_BLK_CGROUP_MODULE)
	19
	20	#ifndef CONFIG_BLK_CGROUP
	21	/* When blk-cgroup is a module, its subsys_id isn't a compile-time constant */
	22	extern struct cgroup_subsys blkio_subsys;
	23	#define blkio_subsys_id blkio_subsys.subsys_id
	24	#endif
2f5ea477	25
84c124da DS	26	enum stat_type {
	27	/* Total time spent (in ns) between request dispatch to the driver and
	28	* request completion for IOs doen by this cgroup. This may not be
	29	* accurate when NCQ is turned on. */
	30	BLKIO_STAT_SERVICE_TIME = 0,
	31	/* Total bytes transferred */
	32	BLKIO_STAT_SERVICE_BYTES,
	33	/* Total IOs serviced, post merge */
	34	BLKIO_STAT_SERVICED,
	35	/* Total time spent waiting in scheduler queue in ns */
	36	BLKIO_STAT_WAIT_TIME,
	37	/* All the single valued stats go below this */
	38	BLKIO_STAT_TIME,
	39	BLKIO_STAT_SECTORS,
	40	#ifdef CONFIG_DEBUG_BLK_CGROUP
	41	BLKIO_STAT_DEQUEUE
	42	#endif
	43	};
	44
	45	enum stat_sub_type {
	46	BLKIO_STAT_READ = 0,
	47	BLKIO_STAT_WRITE,
	48	BLKIO_STAT_SYNC,
	49	BLKIO_STAT_ASYNC,
	50	BLKIO_STAT_TOTAL
303a3acb DS	51	};
303a3acb DS	52
31e4c28d VG	53	struct blkio_cgroup {
	54	struct cgroup_subsys_state css;
	55	unsigned int weight;
	56	spinlock_t lock;
	57	struct hlist_head blkg_list;
	58	};
	59
303a3acb DS	60	struct blkio_group_stats {
	61	/* total disk time and nr sectors dispatched by this group */
	62	uint64_t time;
	63	uint64_t sectors;
84c124da	64	uint64_t stat_arr[BLKIO_STAT_WAIT_TIME + 1][BLKIO_STAT_TOTAL];
303a3acb DS	65	#ifdef CONFIG_DEBUG_BLK_CGROUP
	66	/* How many times this group has been removed from service tree */
	67	unsigned long dequeue;
	68	#endif
	69	};
	70
31e4c28d VG	71	struct blkio_group {
	72	/* An rcu protected unique identifier for the group */
	73	void *key;
	74	struct hlist_node blkcg_node;
b1c35769	75	unsigned short blkcg_id;
2868ef7b VG	76	#ifdef CONFIG_DEBUG_BLK_CGROUP
	77	/* Store cgroup path */
	78	char path[128];
	79	#endif
22084190	80	/* The device MKDEV(major, minor), this group has been created for */
84c124da	81	dev_t dev;
22084190	82
303a3acb DS	83	/* Need to serialize the stats in the case of reset/update */
	84	spinlock_t stats_lock;
	85	struct blkio_group_stats stats;
31e4c28d VG	86	};
31e4c28d VG	87
3e252066 VG	88	typedef void (blkio_unlink_group_fn) (void key, struct blkio_group blkg);
	89	typedef void (blkio_update_group_weight_fn) (struct blkio_group *blkg,
	90	unsigned int weight);
	91
	92	struct blkio_policy_ops {
	93	blkio_unlink_group_fn *blkio_unlink_group_fn;
	94	blkio_update_group_weight_fn *blkio_update_group_weight_fn;
	95	};
	96
	97	struct blkio_policy_type {
	98	struct list_head list;
	99	struct blkio_policy_ops ops;
	100	};
	101
	102	/* Blkio controller policy registration */
	103	extern void blkio_policy_register(struct blkio_policy_type *);
	104	extern void blkio_policy_unregister(struct blkio_policy_type *);
	105
2f5ea477 JA	106	#else
	107
	108	struct blkio_group {
	109	};
	110
3e252066 VG	111	struct blkio_policy_type {
	112	};
	113
	114	static inline void blkio_policy_register(struct blkio_policy_type *blkiop) { }
	115	static inline void blkio_policy_unregister(struct blkio_policy_type *blkiop) { }
	116
2f5ea477 JA	117	#endif
2f5ea477 JA	118
31e4c28d VG	119	#define BLKIO_WEIGHT_MIN 100
	120	#define BLKIO_WEIGHT_MAX 1000
	121	#define BLKIO_WEIGHT_DEFAULT 500
	122
2868ef7b VG	123	#ifdef CONFIG_DEBUG_BLK_CGROUP
	124	static inline char blkg_path(struct blkio_group blkg)
	125	{
	126	return blkg->path;
	127	}
9195291e	128	void blkiocg_update_dequeue_stats(struct blkio_group *blkg,
22084190	129	unsigned long dequeue);
2868ef7b VG	130	#else
2868ef7b VG	131	static inline char blkg_path(struct blkio_group blkg) { return NULL; }
9195291e DS	132	static inline void blkiocg_update_dequeue_stats(struct blkio_group *blkg,
9195291e DS	133	unsigned long dequeue) {}
2868ef7b VG	134	#endif
2868ef7b VG	135
67523c48	136	#if defined(CONFIG_BLK_CGROUP) \|\| defined(CONFIG_BLK_CGROUP_MODULE)
31e4c28d VG	137	extern struct blkio_cgroup blkio_root_cgroup;
	138	extern struct blkio_cgroup cgroup_to_blkio_cgroup(struct cgroup cgroup);
	139	extern void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
22084190	140	struct blkio_group blkg, void key, dev_t dev);
31e4c28d VG	141	extern int blkiocg_del_blkio_group(struct blkio_group *blkg);
	142	extern struct blkio_group blkiocg_lookup_group(struct blkio_cgroup blkcg,
	143	void *key);
84c124da	144	void blkio_group_init(struct blkio_group *blkg);
303a3acb DS	145	void blkiocg_update_timeslice_used(struct blkio_group *blkg,
303a3acb DS	146	unsigned long time);
84c124da DS	147	void blkiocg_update_dispatch_stats(struct blkio_group *blkg, uint64_t bytes,
	148	bool direction, bool sync);
	149	void blkiocg_update_completion_stats(struct blkio_group *blkg,
	150	uint64_t start_time, uint64_t io_start_time, bool direction, bool sync);
31e4c28d	151	#else
2f5ea477	152	struct cgroup;
31e4c28d VG	153	static inline struct blkio_cgroup *
	154	cgroup_to_blkio_cgroup(struct cgroup *cgroup) { return NULL; }
	155
84c124da	156	static inline void blkio_group_init(struct blkio_group *blkg) {}
31e4c28d	157	static inline void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
84c124da	158	struct blkio_group blkg, void key, dev_t dev) {}
31e4c28d VG	159
	160	static inline int
	161	blkiocg_del_blkio_group(struct blkio_group *blkg) { return 0; }
	162
	163	static inline struct blkio_group *
	164	blkiocg_lookup_group(struct blkio_cgroup blkcg, void key) { return NULL; }
303a3acb	165	static inline void blkiocg_update_timeslice_used(struct blkio_group *blkg,
9a0785b0	166	unsigned long time) {}
84c124da DS	167	static inline void blkiocg_update_dispatch_stats(struct blkio_group *blkg,
	168	uint64_t bytes, bool direction, bool sync) {}
	169	static inline void blkiocg_update_completion_stats(struct blkio_group *blkg,
	170	uint64_t start_time, uint64_t io_start_time, bool direction,
	171	bool sync) {}
31e4c28d VG	172	#endif
31e4c28d VG	173	#endif /* _BLK_CGROUP_H */