4 * Common Block IO controller cgroup interface
6 * Based on ideas and code from CFQ, CFS and BFQ:
7 * Copyright (C) 2003 Jens Axboe <axboe@kernel.dk>
9 * Copyright (C) 2008 Fabio Checconi <fabio@gandalf.sssup.it>
10 * Paolo Valente <paolo.valente@unimore.it>
12 * Copyright (C) 2009 Vivek Goyal <vgoyal@redhat.com>
13 * Nauman Rafique <nauman@google.com>
16 #include <linux/cgroup.h>
18 #ifdef CONFIG_BLK_CGROUP
21 struct cgroup_subsys_state css;
24 struct hlist_head blkg_list;
28 /* An rcu protected unique identifier for the group */
30 struct hlist_node blkcg_node;
31 unsigned short blkcg_id;
32 #ifdef CONFIG_DEBUG_BLK_CGROUP
33 /* Store cgroup path */
35 /* How many times this group has been removed from service tree */
36 unsigned long dequeue;
38 /* The device MKDEV(major, minor), this group has been created for */
41 /* total disk time and nr sectors dispatched by this group */
43 unsigned long sectors;
46 extern bool blkiocg_css_tryget(struct blkio_cgroup *blkcg);
47 extern void blkiocg_css_put(struct blkio_cgroup *blkcg);
56 #define BLKIO_WEIGHT_MIN 100
57 #define BLKIO_WEIGHT_MAX 1000
58 #define BLKIO_WEIGHT_DEFAULT 500
60 #ifdef CONFIG_DEBUG_BLK_CGROUP
61 static inline char *blkg_path(struct blkio_group *blkg)
65 void blkiocg_update_blkio_group_dequeue_stats(struct blkio_group *blkg,
66 unsigned long dequeue);
68 static inline char *blkg_path(struct blkio_group *blkg) { return NULL; }
69 static inline void blkiocg_update_blkio_group_dequeue_stats(
70 struct blkio_group *blkg, unsigned long dequeue) {}
73 #ifdef CONFIG_BLK_CGROUP
74 extern struct blkio_cgroup blkio_root_cgroup;
75 extern struct blkio_cgroup *cgroup_to_blkio_cgroup(struct cgroup *cgroup);
76 extern void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
77 struct blkio_group *blkg, void *key, dev_t dev);
78 extern int blkiocg_del_blkio_group(struct blkio_group *blkg);
79 extern struct blkio_group *blkiocg_lookup_group(struct blkio_cgroup *blkcg,
81 void blkiocg_update_blkio_group_stats(struct blkio_group *blkg,
82 unsigned long time, unsigned long sectors);
85 static inline struct blkio_cgroup *
86 cgroup_to_blkio_cgroup(struct cgroup *cgroup) { return NULL; }
88 static inline void blkiocg_add_blkio_group(struct blkio_cgroup *blkcg,
89 struct blkio_group *blkg, void *key, dev_t dev)
94 blkiocg_del_blkio_group(struct blkio_group *blkg) { return 0; }
96 static inline struct blkio_group *
97 blkiocg_lookup_group(struct blkio_cgroup *blkcg, void *key) { return NULL; }
98 static inline void blkiocg_update_blkio_group_stats(struct blkio_group *blkg,
99 unsigned long time, unsigned long sectors)
103 #endif /* _BLK_CGROUP_H */