Merge branch 'master' of ssh://router/data/git/fio
[fio.git] / engines / syslet-rw.c
CommitLineData
a4f4fdd7 1/*
da751ca9
JA
2 * syslet engine
3 *
4 * IO engine that does regular pread(2)/pwrite(2) to transfer data, but
5 * with syslets to make the execution async.
a4f4fdd7
JA
6 *
7 */
8#include <stdio.h>
9#include <stdlib.h>
10#include <unistd.h>
11#include <errno.h>
12#include <assert.h>
12cbb469 13#include <malloc.h>
b8846354 14#include <asm/unistd.h>
a4f4fdd7
JA
15
16#include "../fio.h"
eef32359 17#include "../lib/fls.h"
a4f4fdd7
JA
18
19#ifdef FIO_HAVE_SYSLET
20
1760e679
JA
21#ifdef __NR_pread64
22#define __NR_fio_pread __NR_pread64
23#define __NR_fio_pwrite __NR_pwrite64
24#else
25#define __NR_fio_pread __NR_pread
26#define __NR_fio_pwrite __NR_pwrite
27#endif
28
a4f4fdd7
JA
29struct syslet_data {
30 struct io_u **events;
31 unsigned int nr_events;
32
12cbb469 33 struct syslet_ring *ring;
db6defc7 34 unsigned int ring_mask;
12cbb469 35 void *stack;
a4f4fdd7
JA
36};
37
c6effc3e 38static void fio_syslet_add_event(struct thread_data *td, struct io_u *io_u)
9ff9de69
JA
39{
40 struct syslet_data *sd = td->io_ops->data;
9ff9de69 41
12cbb469
JA
42 assert(sd->nr_events < td->o.iodepth);
43 sd->events[sd->nr_events++] = io_u;
44}
9ff9de69 45
c6effc3e 46static void fio_syslet_add_events(struct thread_data *td, unsigned int nr)
12cbb469
JA
47{
48 struct syslet_data *sd = td->io_ops->data;
db6defc7
JA
49 unsigned int i, uidx;
50
51 uidx = sd->ring->user_tail;
52 read_barrier();
9ff9de69 53
12cbb469 54 for (i = 0; i < nr; i++) {
db6defc7 55 unsigned int idx = (i + uidx) & sd->ring_mask;
12cbb469
JA
56 struct syslet_completion *comp = &sd->ring->comp[idx];
57 struct io_u *io_u = (struct io_u *) (long) comp->caller_data;
c6effc3e
JA
58 long ret;
59
60 ret = comp->status;
61 if (ret <= 0) {
62 io_u->resid = io_u->xfer_buflen;
63 io_u->error = -ret;
64 } else {
65 io_u->resid = io_u->xfer_buflen - ret;
66 io_u->error = 0;
67 }
5b38ee84 68
c6effc3e 69 fio_syslet_add_event(td, io_u);
12cbb469 70 }
9ff9de69
JA
71}
72
12cbb469 73static void fio_syslet_wait_for_events(struct thread_data *td)
a4f4fdd7
JA
74{
75 struct syslet_data *sd = td->io_ops->data;
12cbb469 76 struct syslet_ring *ring = sd->ring;
a4f4fdd7
JA
77
78 do {
12cbb469
JA
79 unsigned int kh = ring->kernel_head;
80 int ret;
a4f4fdd7 81
12cbb469
JA
82 /*
83 * first reap events that are already completed
84 */
85 if (ring->user_tail != kh) {
86 unsigned int nr = kh - ring->user_tail;
a4f4fdd7 87
c6effc3e 88 fio_syslet_add_events(td, nr);
12cbb469 89 ring->user_tail = kh;
4a88edf7 90 break;
12cbb469 91 }
a4f4fdd7 92
12cbb469
JA
93 /*
94 * block waiting for at least one event
95 */
96 ret = syscall(__NR_syslet_ring_wait, ring, ring->user_tail);
97 assert(!ret);
4a88edf7 98 } while (1);
a4f4fdd7
JA
99}
100
e7d2e616
JA
101static int fio_syslet_getevents(struct thread_data *td, unsigned int min,
102 unsigned int fio_unused max,
a4f4fdd7
JA
103 struct timespec fio_unused *t)
104{
105 struct syslet_data *sd = td->io_ops->data;
a4f4fdd7
JA
106 long ret;
107
4a88edf7
JA
108 /*
109 * While we have less events than requested, block waiting for them
a3cc770d
JA
110 * (if we have to, there may already be more completed events ready
111 * for us - see fio_syslet_wait_for_events()
4a88edf7 112 */
a3cc770d 113 while (sd->nr_events < min)
12cbb469 114 fio_syslet_wait_for_events(td);
a4f4fdd7
JA
115
116 ret = sd->nr_events;
117 sd->nr_events = 0;
118 return ret;
119}
120
121static struct io_u *fio_syslet_event(struct thread_data *td, int event)
122{
123 struct syslet_data *sd = td->io_ops->data;
124
125 return sd->events[event];
126}
127
12cbb469
JA
128static void fio_syslet_prep_sync(struct fio_file *f,
129 struct indirect_registers *regs)
a4f4fdd7 130{
12cbb469 131 FILL_IN(*regs, __NR_fsync, (long) f->fd);
a4f4fdd7
JA
132}
133
12cbb469
JA
134static void fio_syslet_prep_rw(struct io_u *io_u, struct fio_file *f,
135 struct indirect_registers *regs)
a4f4fdd7 136{
12cbb469 137 long nr;
a4f4fdd7 138
a4f4fdd7
JA
139 /*
140 * prepare rw
141 */
142 if (io_u->ddir == DDIR_READ)
1760e679 143 nr = __NR_fio_pread;
a4f4fdd7 144 else
1760e679 145 nr = __NR_fio_pwrite;
a4f4fdd7 146
12cbb469
JA
147 FILL_IN(*regs, nr, (long) f->fd, (long) io_u->xfer_buf,
148 (long) io_u->xfer_buflen, (long) io_u->offset);
a4f4fdd7
JA
149}
150
12cbb469 151static void fio_syslet_prep(struct io_u *io_u, struct indirect_registers *regs)
a4f4fdd7
JA
152{
153 struct fio_file *f = io_u->file;
154
155 if (io_u->ddir == DDIR_SYNC)
12cbb469 156 fio_syslet_prep_sync(f, regs);
a4f4fdd7 157 else
12cbb469 158 fio_syslet_prep_rw(io_u, f, regs);
a0a930ef
JA
159}
160
12cbb469 161static void ret_func(void)
a4f4fdd7 162{
12cbb469 163 syscall(__NR_exit);
9ff9de69
JA
164}
165
166static int fio_syslet_queue(struct thread_data *td, struct io_u *io_u)
167{
168 struct syslet_data *sd = td->io_ops->data;
12cbb469
JA
169 union indirect_params params;
170 struct indirect_registers regs;
171 int ret;
bf0dc8fa 172
7101d9c2
JA
173 fio_ro_check(td, io_u);
174
12cbb469
JA
175 memset(&params, 0, sizeof(params));
176 fill_syslet_args(&params.syslet, sd->ring, (long)io_u, ret_func, sd->stack);
a4f4fdd7 177
12cbb469 178 fio_syslet_prep(io_u, &regs);
2ca50be4 179
12cbb469
JA
180 ret = syscall(__NR_indirect, &regs, &params, sizeof(params), 0);
181 if (ret == (int) io_u->xfer_buflen) {
182 /*
183 * completed sync, account. this also catches fsync().
184 */
185 return FIO_Q_COMPLETED;
186 } else if (ret < 0) {
187 /*
188 * queued for async execution
189 */
190 if (errno == ESYSLETPENDING)
191 return FIO_Q_QUEUED;
192 }
a4f4fdd7 193
12cbb469
JA
194 io_u->error = errno;
195 td_verror(td, io_u->error, "xfer");
196 return FIO_Q_COMPLETED;
a4f4fdd7
JA
197}
198
76f58b92
JA
199static int check_syslet_support(struct syslet_data *sd)
200{
12cbb469
JA
201 union indirect_params params;
202 struct indirect_registers regs;
203 pid_t pid, my_pid = getpid();
76f58b92 204
12cbb469
JA
205 memset(&params, 0, sizeof(params));
206 fill_syslet_args(&params.syslet, sd->ring, 0, ret_func, sd->stack);
76f58b92 207
12cbb469
JA
208 FILL_IN(regs, __NR_getpid);
209
210 pid = syscall(__NR_indirect, &regs, &params, sizeof(params), 0);
211 if (pid == my_pid)
212 return 0;
213
214 return 1;
76f58b92
JA
215}
216
a4f4fdd7
JA
217static void fio_syslet_cleanup(struct thread_data *td)
218{
219 struct syslet_data *sd = td->io_ops->data;
220
221 if (sd) {
a4f4fdd7 222 free(sd->events);
12cbb469 223 free(sd->ring);
a4f4fdd7 224 free(sd);
a4f4fdd7
JA
225 }
226}
227
228static int fio_syslet_init(struct thread_data *td)
229{
230 struct syslet_data *sd;
e81f7340 231 void *ring = NULL, *stack = NULL;
05f6a172 232 unsigned int ring_size, ring_nr;
a4f4fdd7
JA
233
234 sd = malloc(sizeof(*sd));
235 memset(sd, 0, sizeof(*sd));
12cbb469 236
2dc1bbeb
JA
237 sd->events = malloc(sizeof(struct io_u *) * td->o.iodepth);
238 memset(sd->events, 0, sizeof(struct io_u *) * td->o.iodepth);
05f6a172
JA
239
240 /*
241 * The ring needs to be a power-of-2, so round it up if we have to
242 */
243 ring_nr = td->o.iodepth;
e6026f9c 244 if (ring_nr & (ring_nr - 1))
0ae38eba 245 ring_nr = 1 << __fls(ring_nr);
05f6a172
JA
246
247 ring_size = sizeof(struct syslet_ring) +
248 ring_nr * sizeof(struct syslet_completion);
249 if (posix_memalign(&ring, sizeof(uint64_t), ring_size))
e81f7340 250 goto err_mem;
12cbb469 251 if (posix_memalign(&stack, page_size, page_size))
e81f7340 252 goto err_mem;
12cbb469
JA
253
254 sd->ring = ring;
db6defc7 255 sd->ring_mask = ring_nr - 1;
12cbb469
JA
256 sd->stack = stack;
257
05f6a172
JA
258 memset(sd->ring, 0, ring_size);
259 sd->ring->elements = ring_nr;
db64e9bc 260
e81f7340
JA
261 if (!check_syslet_support(sd)) {
262 td->io_ops->data = sd;
263 return 0;
76f58b92
JA
264 }
265
e81f7340
JA
266 log_err("fio: syslets do not appear to work\n");
267err_mem:
268 free(sd->events);
269 if (ring)
270 free(ring);
271 if (stack)
272 free(stack);
273 free(sd);
274 return 1;
a4f4fdd7
JA
275}
276
277static struct ioengine_ops ioengine = {
278 .name = "syslet-rw",
279 .version = FIO_IOOPS_VERSION,
280 .init = fio_syslet_init,
a4f4fdd7
JA
281 .queue = fio_syslet_queue,
282 .getevents = fio_syslet_getevents,
283 .event = fio_syslet_event,
284 .cleanup = fio_syslet_cleanup,
b5af8293
JA
285 .open_file = generic_open_file,
286 .close_file = generic_close_file,
df9c26b1 287 .get_file_size = generic_get_file_size,
a4f4fdd7
JA
288};
289
290#else /* FIO_HAVE_SYSLET */
291
292/*
293 * When we have a proper configure system in place, we simply wont build
294 * and install this io engine. For now install a crippled version that
295 * just complains and fails to load.
296 */
297static int fio_syslet_init(struct thread_data fio_unused *td)
298{
299 fprintf(stderr, "fio: syslet not available\n");
300 return 1;
301}
302
303static struct ioengine_ops ioengine = {
304 .name = "syslet-rw",
305 .version = FIO_IOOPS_VERSION,
306 .init = fio_syslet_init,
307};
308
309#endif /* FIO_HAVE_SYSLET */
310
311static void fio_init fio_syslet_register(void)
312{
313 register_ioengine(&ioengine);
314}
315
316static void fio_exit fio_syslet_unregister(void)
317{
318 unregister_ioengine(&ioengine);
319}