| 1 | /* |
| 2 | * null engine |
| 3 | * |
| 4 | * IO engine that doesn't do any real IO transfers, it just pretends to. |
| 5 | * The main purpose is to test fio itself. |
| 6 | * |
| 7 | * It also can act as external C++ engine - compiled with: |
| 8 | * |
| 9 | * g++ -O2 -g -shared -rdynamic -fPIC -o cpp_null null.c -DFIO_EXTERNAL_ENGINE |
| 10 | * |
| 11 | * to test it execute: |
| 12 | * |
| 13 | * LD_LIBRARY_PATH=./engines ./fio examples/cpp_null.fio |
| 14 | * |
| 15 | */ |
| 16 | #include <stdio.h> |
| 17 | #include <stdlib.h> |
| 18 | #include <unistd.h> |
| 19 | #include <errno.h> |
| 20 | #include <assert.h> |
| 21 | |
| 22 | #include "../fio.h" |
| 23 | |
| 24 | struct null_data { |
| 25 | struct io_u **io_us; |
| 26 | int queued; |
| 27 | int events; |
| 28 | }; |
| 29 | |
| 30 | static struct io_u *null_event(struct null_data *nd, int event) |
| 31 | { |
| 32 | return nd->io_us[event]; |
| 33 | } |
| 34 | |
| 35 | static int null_getevents(struct null_data *nd, unsigned int min_events, |
| 36 | unsigned int fio_unused max, |
| 37 | const struct timespec fio_unused *t) |
| 38 | { |
| 39 | int ret = 0; |
| 40 | |
| 41 | if (min_events) { |
| 42 | ret = nd->events; |
| 43 | nd->events = 0; |
| 44 | } |
| 45 | |
| 46 | return ret; |
| 47 | } |
| 48 | |
| 49 | static int null_commit(struct thread_data *td, struct null_data *nd) |
| 50 | { |
| 51 | if (!nd->events) { |
| 52 | #ifndef FIO_EXTERNAL_ENGINE |
| 53 | io_u_mark_submit(td, nd->queued); |
| 54 | #endif |
| 55 | nd->events = nd->queued; |
| 56 | nd->queued = 0; |
| 57 | } |
| 58 | |
| 59 | return 0; |
| 60 | } |
| 61 | |
| 62 | static int null_queue(struct thread_data *td, struct null_data *nd, |
| 63 | struct io_u *io_u) |
| 64 | { |
| 65 | fio_ro_check(td, io_u); |
| 66 | |
| 67 | if (td->io_ops->flags & FIO_SYNCIO) |
| 68 | return FIO_Q_COMPLETED; |
| 69 | if (nd->events) |
| 70 | return FIO_Q_BUSY; |
| 71 | |
| 72 | nd->io_us[nd->queued++] = io_u; |
| 73 | return FIO_Q_QUEUED; |
| 74 | } |
| 75 | |
| 76 | static int null_open(struct null_data fio_unused *nd, |
| 77 | struct fio_file fio_unused *f) |
| 78 | { |
| 79 | return 0; |
| 80 | } |
| 81 | |
| 82 | static void null_cleanup(struct null_data *nd) |
| 83 | { |
| 84 | if (nd) { |
| 85 | free(nd->io_us); |
| 86 | free(nd); |
| 87 | } |
| 88 | } |
| 89 | |
| 90 | static int null_init(struct thread_data *td, struct null_data **nd_ptr) |
| 91 | { |
| 92 | struct null_data *nd = (struct null_data *) malloc(sizeof(**nd_ptr)); |
| 93 | |
| 94 | memset(nd, 0, sizeof(*nd)); |
| 95 | |
| 96 | if (td->o.iodepth != 1) { |
| 97 | nd->io_us = (struct io_u **) malloc(td->o.iodepth * sizeof(struct io_u *)); |
| 98 | memset(nd->io_us, 0, td->o.iodepth * sizeof(struct io_u *)); |
| 99 | } else |
| 100 | td->io_ops->flags |= FIO_SYNCIO; |
| 101 | |
| 102 | *nd_ptr = nd; |
| 103 | return 0; |
| 104 | } |
| 105 | |
| 106 | #ifndef __cplusplus |
| 107 | |
| 108 | static struct io_u *fio_null_event(struct thread_data *td, int event) |
| 109 | { |
| 110 | return null_event((struct null_data *)td->io_ops_data, event); |
| 111 | } |
| 112 | |
| 113 | static int fio_null_getevents(struct thread_data *td, unsigned int min_events, |
| 114 | unsigned int max, const struct timespec *t) |
| 115 | { |
| 116 | struct null_data *nd = (struct null_data *)td->io_ops_data; |
| 117 | return null_getevents(nd, min_events, max, t); |
| 118 | } |
| 119 | |
| 120 | static int fio_null_commit(struct thread_data *td) |
| 121 | { |
| 122 | return null_commit(td, (struct null_data *)td->io_ops_data); |
| 123 | } |
| 124 | |
| 125 | static int fio_null_queue(struct thread_data *td, struct io_u *io_u) |
| 126 | { |
| 127 | return null_queue(td, (struct null_data *)td->io_ops_data, io_u); |
| 128 | } |
| 129 | |
| 130 | static int fio_null_open(struct thread_data *td, struct fio_file *f) |
| 131 | { |
| 132 | return null_open((struct null_data *)td->io_ops_data, f); |
| 133 | } |
| 134 | |
| 135 | static void fio_null_cleanup(struct thread_data *td) |
| 136 | { |
| 137 | null_cleanup((struct null_data *)td->io_ops_data); |
| 138 | } |
| 139 | |
| 140 | static int fio_null_init(struct thread_data *td) |
| 141 | { |
| 142 | return null_init(td, (struct null_data **)&td->io_ops_data); |
| 143 | } |
| 144 | |
| 145 | static struct ioengine_ops ioengine = { |
| 146 | .name = "null", |
| 147 | .version = FIO_IOOPS_VERSION, |
| 148 | .queue = fio_null_queue, |
| 149 | .commit = fio_null_commit, |
| 150 | .getevents = fio_null_getevents, |
| 151 | .event = fio_null_event, |
| 152 | .init = fio_null_init, |
| 153 | .cleanup = fio_null_cleanup, |
| 154 | .open_file = fio_null_open, |
| 155 | .flags = FIO_DISKLESSIO | FIO_FAKEIO, |
| 156 | }; |
| 157 | |
| 158 | static void fio_init fio_null_register(void) |
| 159 | { |
| 160 | register_ioengine(&ioengine); |
| 161 | } |
| 162 | |
| 163 | static void fio_exit fio_null_unregister(void) |
| 164 | { |
| 165 | unregister_ioengine(&ioengine); |
| 166 | } |
| 167 | |
| 168 | #else |
| 169 | |
| 170 | #ifdef FIO_EXTERNAL_ENGINE |
| 171 | |
| 172 | struct NullData { |
| 173 | NullData(struct thread_data *td) |
| 174 | { |
| 175 | null_init(td, &impl_); |
| 176 | } |
| 177 | |
| 178 | ~NullData() |
| 179 | { |
| 180 | null_cleanup(impl_); |
| 181 | } |
| 182 | |
| 183 | static NullData *get(struct thread_data *td) |
| 184 | { |
| 185 | return reinterpret_cast<NullData *>(td->io_ops_data); |
| 186 | } |
| 187 | |
| 188 | io_u *fio_null_event(struct thread_data *, int event) |
| 189 | { |
| 190 | return null_event(impl_, event); |
| 191 | } |
| 192 | |
| 193 | int fio_null_getevents(struct thread_data *, unsigned int min_events, |
| 194 | unsigned int max, const struct timespec *t) |
| 195 | { |
| 196 | return null_getevents(impl_, min_events, max, t); |
| 197 | } |
| 198 | |
| 199 | int fio_null_commit(struct thread_data *td) |
| 200 | { |
| 201 | return null_commit(td, impl_); |
| 202 | } |
| 203 | |
| 204 | int fio_null_queue(struct thread_data *td, struct io_u *io_u) |
| 205 | { |
| 206 | return null_queue(td, impl_, io_u); |
| 207 | } |
| 208 | |
| 209 | int fio_null_open(struct thread_data *, struct fio_file *f) |
| 210 | { |
| 211 | return null_open(impl_, f); |
| 212 | } |
| 213 | |
| 214 | struct null_data *impl_; |
| 215 | }; |
| 216 | |
| 217 | extern "C" { |
| 218 | |
| 219 | static struct io_u *fio_null_event(struct thread_data *td, int event) |
| 220 | { |
| 221 | return NullData::get(td)->fio_null_event(td, event); |
| 222 | } |
| 223 | |
| 224 | static int fio_null_getevents(struct thread_data *td, unsigned int min_events, |
| 225 | unsigned int max, const struct timespec *t) |
| 226 | { |
| 227 | return NullData::get(td)->fio_null_getevents(td, min_events, max, t); |
| 228 | } |
| 229 | |
| 230 | static int fio_null_commit(struct thread_data *td) |
| 231 | { |
| 232 | return NullData::get(td)->fio_null_commit(td); |
| 233 | } |
| 234 | |
| 235 | static int fio_null_queue(struct thread_data *td, struct io_u *io_u) |
| 236 | { |
| 237 | return NullData::get(td)->fio_null_queue(td, io_u); |
| 238 | } |
| 239 | |
| 240 | static int fio_null_open(struct thread_data *td, struct fio_file *f) |
| 241 | { |
| 242 | return NullData::get(td)->fio_null_open(td, f); |
| 243 | } |
| 244 | |
| 245 | static int fio_null_init(struct thread_data *td) |
| 246 | { |
| 247 | td->io_ops_data = new NullData(td); |
| 248 | return 0; |
| 249 | } |
| 250 | |
| 251 | static void fio_null_cleanup(struct thread_data *td) |
| 252 | { |
| 253 | delete NullData::get(td); |
| 254 | } |
| 255 | |
| 256 | static struct ioengine_ops ioengine; |
| 257 | void get_ioengine(struct ioengine_ops **ioengine_ptr) |
| 258 | { |
| 259 | *ioengine_ptr = &ioengine; |
| 260 | |
| 261 | ioengine.name = "cpp_null"; |
| 262 | ioengine.version = FIO_IOOPS_VERSION; |
| 263 | ioengine.queue = fio_null_queue; |
| 264 | ioengine.commit = fio_null_commit; |
| 265 | ioengine.getevents = fio_null_getevents; |
| 266 | ioengine.event = fio_null_event; |
| 267 | ioengine.init = fio_null_init; |
| 268 | ioengine.cleanup = fio_null_cleanup; |
| 269 | ioengine.open_file = fio_null_open; |
| 270 | ioengine.flags = FIO_DISKLESSIO | FIO_FAKEIO; |
| 271 | } |
| 272 | } |
| 273 | #endif /* FIO_EXTERNAL_ENGINE */ |
| 274 | |
| 275 | #endif /* __cplusplus */ |