4 #include <linux/radix-tree.h>
5 #include <linux/rcupdate.h>
6 #include <linux/workqueue.h>
10 unsigned long last_end_request
;
12 unsigned long ttime_total
;
13 unsigned long ttime_samples
;
14 unsigned long ttime_mean
;
22 struct cfq_io_context
{
23 struct request_queue
*q
;
25 struct cfq_queue
*cfqq
[2];
27 struct io_context
*ioc
;
29 struct cfq_ttime ttime
;
31 struct list_head queue_list
;
32 struct hlist_node cic_list
;
34 unsigned long changed
;
36 void (*exit
)(struct cfq_io_context
*);
37 void (*release
)(struct cfq_io_context
*);
39 struct rcu_head rcu_head
;
43 * I/O subsystem state of the associated processes. It is refcounted
44 * and kmalloc'ed. These could be shared between processes.
47 atomic_long_t refcount
;
50 /* all the fields below are protected by this lock */
53 unsigned short ioprio
;
56 * For request batching
58 int nr_batch_requests
; /* Number of requests left in the batch */
59 unsigned long last_waited
; /* Time last woken after wait for request */
61 struct radix_tree_root radix_root
;
62 struct hlist_head cic_list
;
65 struct work_struct release_work
;
68 static inline struct io_context
*ioc_task_link(struct io_context
*ioc
)
71 * if ref count is zero, don't allow sharing (ioc is going away, it's
74 if (ioc
&& atomic_long_inc_not_zero(&ioc
->refcount
)) {
75 atomic_inc(&ioc
->nr_tasks
);
84 void put_io_context(struct io_context
*ioc
, struct request_queue
*locked_q
);
85 void exit_io_context(struct task_struct
*task
);
86 struct io_context
*get_task_io_context(struct task_struct
*task
,
87 gfp_t gfp_flags
, int node
);
88 void ioc_ioprio_changed(struct io_context
*ioc
, int ioprio
);
89 void ioc_cgroup_changed(struct io_context
*ioc
);
92 static inline void put_io_context(struct io_context
*ioc
,
93 struct request_queue
*locked_q
) { }
94 static inline void exit_io_context(struct task_struct
*task
) { }