| | 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 | unsigned int id; |
| | 9 | struct flist_head list; |
| | 10 | unsigned long flow_counter; |
| | 11 | unsigned int total_weight; |
| | 12 | }; |
| | 13 | |
| | 14 | static struct flist_head *flow_list; |
| | 15 | static struct fio_sem *flow_lock; |
| | 16 | |
| | 17 | int flow_threshold_exceeded(struct thread_data *td) |
| | 18 | { |
| | 19 | struct fio_flow *flow = td->flow; |
| | 20 | double flow_counter_ratio, flow_weight_ratio; |
| | 21 | |
| | 22 | if (!flow) |
| | 23 | return 0; |
| | 24 | |
| | 25 | flow_counter_ratio = (double)td->flow_counter / |
| | 26 | atomic_load_relaxed(&flow->flow_counter); |
| | 27 | flow_weight_ratio = (double)td->o.flow / |
| | 28 | atomic_load_relaxed(&flow->total_weight); |
| | 29 | |
| | 30 | /* |
| | 31 | * each thread/process executing a fio job will stall based on the |
| | 32 | * expected user ratio for a given flow_id group. the idea is to keep |
| | 33 | * 2 counters, flow and job-specific counter to test if the |
| | 34 | * ratio between them is proportional to other jobs in the same flow_id |
| | 35 | */ |
| | 36 | if (flow_counter_ratio > flow_weight_ratio) { |
| | 37 | if (td->o.flow_sleep) { |
| | 38 | io_u_quiesce(td); |
| | 39 | usleep(td->o.flow_sleep); |
| | 40 | } |
| | 41 | |
| | 42 | return 1; |
| | 43 | } |
| | 44 | |
| | 45 | /* |
| | 46 | * increment flow(shared counter, therefore atomically) |
| | 47 | * and job-specific counter |
| | 48 | */ |
| | 49 | atomic_add(&flow->flow_counter, 1); |
| | 50 | ++td->flow_counter; |
| | 51 | |
| | 52 | return 0; |
| | 53 | } |
| | 54 | |
| | 55 | static struct fio_flow *flow_get(unsigned int id) |
| | 56 | { |
| | 57 | struct fio_flow *flow = NULL; |
| | 58 | struct flist_head *n; |
| | 59 | |
| | 60 | if (!flow_lock) |
| | 61 | return NULL; |
| | 62 | |
| | 63 | fio_sem_down(flow_lock); |
| | 64 | |
| | 65 | flist_for_each(n, flow_list) { |
| | 66 | flow = flist_entry(n, struct fio_flow, list); |
| | 67 | if (flow->id == id) |
| | 68 | break; |
| | 69 | |
| | 70 | flow = NULL; |
| | 71 | } |
| | 72 | |
| | 73 | if (!flow) { |
| | 74 | flow = smalloc(sizeof(*flow)); |
| | 75 | if (!flow) { |
| | 76 | fio_sem_up(flow_lock); |
| | 77 | return NULL; |
| | 78 | } |
| | 79 | flow->refs = 0; |
| | 80 | INIT_FLIST_HEAD(&flow->list); |
| | 81 | flow->id = id; |
| | 82 | flow->flow_counter = 1; |
| | 83 | flow->total_weight = 0; |
| | 84 | |
| | 85 | flist_add_tail(&flow->list, flow_list); |
| | 86 | } |
| | 87 | |
| | 88 | flow->refs++; |
| | 89 | fio_sem_up(flow_lock); |
| | 90 | return flow; |
| | 91 | } |
| | 92 | |
| | 93 | static void flow_put(struct fio_flow *flow, unsigned long flow_counter, |
| | 94 | unsigned int weight) |
| | 95 | { |
| | 96 | if (!flow_lock) |
| | 97 | return; |
| | 98 | |
| | 99 | fio_sem_down(flow_lock); |
| | 100 | |
| | 101 | atomic_sub(&flow->flow_counter, flow_counter); |
| | 102 | atomic_sub(&flow->total_weight, weight); |
| | 103 | |
| | 104 | if (!--flow->refs) { |
| | 105 | assert(flow->flow_counter == 1); |
| | 106 | flist_del(&flow->list); |
| | 107 | sfree(flow); |
| | 108 | } |
| | 109 | |
| | 110 | fio_sem_up(flow_lock); |
| | 111 | } |
| | 112 | |
| | 113 | void flow_init_job(struct thread_data *td) |
| | 114 | { |
| | 115 | if (td->o.flow) { |
| | 116 | td->flow = flow_get(td->o.flow_id); |
| | 117 | td->flow_counter = 0; |
| | 118 | atomic_add(&td->flow->total_weight, td->o.flow); |
| | 119 | } |
| | 120 | } |
| | 121 | |
| | 122 | void flow_exit_job(struct thread_data *td) |
| | 123 | { |
| | 124 | if (td->flow) { |
| | 125 | flow_put(td->flow, td->flow_counter, td->o.flow); |
| | 126 | td->flow = NULL; |
| | 127 | } |
| | 128 | } |
| | 129 | |
| | 130 | void flow_init(void) |
| | 131 | { |
| | 132 | flow_list = smalloc(sizeof(*flow_list)); |
| | 133 | if (!flow_list) { |
| | 134 | log_err("fio: smalloc pool exhausted\n"); |
| | 135 | return; |
| | 136 | } |
| | 137 | |
| | 138 | flow_lock = fio_sem_init(FIO_SEM_UNLOCKED); |
| | 139 | if (!flow_lock) { |
| | 140 | log_err("fio: failed to allocate flow lock\n"); |
| | 141 | sfree(flow_list); |
| | 142 | return; |
| | 143 | } |
| | 144 | |
| | 145 | INIT_FLIST_HEAD(flow_list); |
| | 146 | } |
| | 147 | |
| | 148 | void flow_exit(void) |
| | 149 | { |
| | 150 | if (flow_lock) |
| | 151 | fio_sem_remove(flow_lock); |
| | 152 | if (flow_list) |
| | 153 | sfree(flow_list); |
| | 154 | } |
projects / fio.git / blame_incremental