| 1 | #include "fio.h" |
| 2 | #include "fio_sem.h" |
| 3 | #include "smalloc.h" |
| 4 | #include "flist.h" |
| 5 | |
| 6 | struct fio_flow { |
| 7 | unsigned int refs; |
| 8 | struct flist_head list; |
| 9 | unsigned int id; |
| 10 | long long int flow_counter; |
| 11 | }; |
| 12 | |
| 13 | static struct flist_head *flow_list; |
| 14 | static struct fio_sem *flow_lock; |
| 15 | |
| 16 | int flow_threshold_exceeded(struct thread_data *td) |
| 17 | { |
| 18 | struct fio_flow *flow = td->flow; |
| 19 | long long flow_counter; |
| 20 | |
| 21 | if (!flow) |
| 22 | return 0; |
| 23 | |
| 24 | if (td->o.flow > 0) |
| 25 | flow_counter = flow->flow_counter; |
| 26 | else |
| 27 | flow_counter = -flow->flow_counter; |
| 28 | |
| 29 | if (flow_counter > td->o.flow_watermark) { |
| 30 | if (td->o.flow_sleep) { |
| 31 | io_u_quiesce(td); |
| 32 | usleep(td->o.flow_sleep); |
| 33 | } |
| 34 | |
| 35 | return 1; |
| 36 | } |
| 37 | |
| 38 | /* No synchronization needed because it doesn't |
| 39 | * matter if the flow count is slightly inaccurate */ |
| 40 | flow->flow_counter += td->o.flow; |
| 41 | return 0; |
| 42 | } |
| 43 | |
| 44 | static struct fio_flow *flow_get(unsigned int id) |
| 45 | { |
| 46 | struct fio_flow *flow = NULL; |
| 47 | struct flist_head *n; |
| 48 | |
| 49 | if (!flow_lock) |
| 50 | return NULL; |
| 51 | |
| 52 | fio_sem_down(flow_lock); |
| 53 | |
| 54 | flist_for_each(n, flow_list) { |
| 55 | flow = flist_entry(n, struct fio_flow, list); |
| 56 | if (flow->id == id) |
| 57 | break; |
| 58 | |
| 59 | flow = NULL; |
| 60 | } |
| 61 | |
| 62 | if (!flow) { |
| 63 | flow = smalloc(sizeof(*flow)); |
| 64 | if (!flow) { |
| 65 | fio_sem_up(flow_lock); |
| 66 | return NULL; |
| 67 | } |
| 68 | flow->refs = 0; |
| 69 | INIT_FLIST_HEAD(&flow->list); |
| 70 | flow->id = id; |
| 71 | flow->flow_counter = 0; |
| 72 | |
| 73 | flist_add_tail(&flow->list, flow_list); |
| 74 | } |
| 75 | |
| 76 | flow->refs++; |
| 77 | fio_sem_up(flow_lock); |
| 78 | return flow; |
| 79 | } |
| 80 | |
| 81 | static void flow_put(struct fio_flow *flow) |
| 82 | { |
| 83 | if (!flow_lock) |
| 84 | return; |
| 85 | |
| 86 | fio_sem_down(flow_lock); |
| 87 | |
| 88 | if (!--flow->refs) { |
| 89 | flist_del(&flow->list); |
| 90 | sfree(flow); |
| 91 | } |
| 92 | |
| 93 | fio_sem_up(flow_lock); |
| 94 | } |
| 95 | |
| 96 | void flow_init_job(struct thread_data *td) |
| 97 | { |
| 98 | if (td->o.flow) |
| 99 | td->flow = flow_get(td->o.flow_id); |
| 100 | } |
| 101 | |
| 102 | void flow_exit_job(struct thread_data *td) |
| 103 | { |
| 104 | if (td->flow) { |
| 105 | flow_put(td->flow); |
| 106 | td->flow = NULL; |
| 107 | } |
| 108 | } |
| 109 | |
| 110 | void flow_init(void) |
| 111 | { |
| 112 | flow_list = smalloc(sizeof(*flow_list)); |
| 113 | if (!flow_list) { |
| 114 | log_err("fio: smalloc pool exhausted\n"); |
| 115 | return; |
| 116 | } |
| 117 | |
| 118 | flow_lock = fio_sem_init(FIO_SEM_UNLOCKED); |
| 119 | if (!flow_lock) { |
| 120 | log_err("fio: failed to allocate flow lock\n"); |
| 121 | sfree(flow_list); |
| 122 | return; |
| 123 | } |
| 124 | |
| 125 | INIT_FLIST_HEAD(flow_list); |
| 126 | } |
| 127 | |
| 128 | void flow_exit(void) |
| 129 | { |
| 130 | if (flow_lock) |
| 131 | fio_sem_remove(flow_lock); |
| 132 | if (flow_list) |
| 133 | sfree(flow_list); |
| 134 | } |