| Jens Axboe | fd0928d | 2008-01-24 08:52:45 +0100 | [diff] [blame^] | 1 | #ifndef IOCONTEXT_H |
| 2 | #define IOCONTEXT_H |
| 3 | |
| 4 | /* |
| 5 | * This is the per-process anticipatory I/O scheduler state. |
| 6 | */ |
| 7 | struct as_io_context { |
| 8 | spinlock_t lock; |
| 9 | |
| 10 | void (*dtor)(struct as_io_context *aic); /* destructor */ |
| 11 | void (*exit)(struct as_io_context *aic); /* called on task exit */ |
| 12 | |
| 13 | unsigned long state; |
| 14 | atomic_t nr_queued; /* queued reads & sync writes */ |
| 15 | atomic_t nr_dispatched; /* number of requests gone to the drivers */ |
| 16 | |
| 17 | /* IO History tracking */ |
| 18 | /* Thinktime */ |
| 19 | unsigned long last_end_request; |
| 20 | unsigned long ttime_total; |
| 21 | unsigned long ttime_samples; |
| 22 | unsigned long ttime_mean; |
| 23 | /* Layout pattern */ |
| 24 | unsigned int seek_samples; |
| 25 | sector_t last_request_pos; |
| 26 | u64 seek_total; |
| 27 | sector_t seek_mean; |
| 28 | }; |
| 29 | |
| 30 | struct cfq_queue; |
| 31 | struct cfq_io_context { |
| 32 | struct rb_node rb_node; |
| 33 | void *key; |
| 34 | |
| 35 | struct cfq_queue *cfqq[2]; |
| 36 | |
| 37 | struct io_context *ioc; |
| 38 | |
| 39 | unsigned long last_end_request; |
| 40 | sector_t last_request_pos; |
| 41 | |
| 42 | unsigned long ttime_total; |
| 43 | unsigned long ttime_samples; |
| 44 | unsigned long ttime_mean; |
| 45 | |
| 46 | unsigned int seek_samples; |
| 47 | u64 seek_total; |
| 48 | sector_t seek_mean; |
| 49 | |
| 50 | struct list_head queue_list; |
| 51 | |
| 52 | void (*dtor)(struct io_context *); /* destructor */ |
| 53 | void (*exit)(struct io_context *); /* called on task exit */ |
| 54 | }; |
| 55 | |
| 56 | /* |
| 57 | * This is the per-process I/O subsystem state. It is refcounted and |
| 58 | * kmalloc'ed. Currently all fields are modified in process io context |
| 59 | * (apart from the atomic refcount), so require no locking. |
| 60 | */ |
| 61 | struct io_context { |
| 62 | atomic_t refcount; |
| 63 | struct task_struct *task; |
| 64 | |
| 65 | unsigned short ioprio; |
| 66 | unsigned short ioprio_changed; |
| 67 | |
| 68 | /* |
| 69 | * For request batching |
| 70 | */ |
| 71 | unsigned long last_waited; /* Time last woken after wait for request */ |
| 72 | int nr_batch_requests; /* Number of requests left in the batch */ |
| 73 | |
| 74 | struct as_io_context *aic; |
| 75 | struct rb_root cic_root; |
| 76 | void *ioc_data; |
| 77 | }; |
| 78 | |
| 79 | #endif |