Add support for redirection replay of blktrace traces to another device
[fio.git] / blktrace.c
CommitLineData
fb7b71a3
JA
1/*
2 * blktrace support code for fio
3 */
4#include <stdio.h>
5#include <stdlib.h>
5e6c2067
JA
6#include <sys/stat.h>
7#include <dirent.h>
8c1fdf04 8
01743ee1 9#include "flist.h"
fb7b71a3
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10#include "fio.h"
11#include "blktrace_api.h"
12
2da7df1d 13#define TRACE_FIFO_SIZE 8192
e2887563
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14
15/*
16 * fifo refill frontend, to avoid reading data in trace sized bites
17 */
18static int refill_fifo(struct thread_data *td, struct fifo *fifo, int fd)
19{
20 char buf[TRACE_FIFO_SIZE];
f12b323f 21 unsigned int total;
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22 int ret;
23
f12b323f
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24 total = sizeof(buf);
25 if (total > fifo_room(fifo))
26 total = fifo_room(fifo);
e2887563 27
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28 ret = read(fd, buf, total);
29 if (ret < 0) {
30 td_verror(td, errno, "read blktrace file");
31 return -1;
e2887563
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32 }
33
f12b323f
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34 if (ret > 0)
35 ret = fifo_put(fifo, buf, ret);
36
bd6f78b2 37 dprint(FD_BLKTRACE, "refill: filled %d bytes\n", ret);
f12b323f 38 return ret;
e2887563
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39}
40
41/*
42 * Retrieve 'len' bytes from the fifo, refilling if necessary.
43 */
44static int trace_fifo_get(struct thread_data *td, struct fifo *fifo, int fd,
45 void *buf, unsigned int len)
46{
f12b323f
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47 if (fifo_len(fifo) < len) {
48 int ret = refill_fifo(td, fifo, fd);
e2887563 49
f12b323f
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50 if (ret < 0)
51 return ret;
52 }
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53
54 return fifo_get(fifo, buf, len);
55}
56
8c1fdf04
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57/*
58 * Just discard the pdu by seeking past it.
59 */
f12b323f
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60static int discard_pdu(struct thread_data *td, struct fifo *fifo, int fd,
61 struct blk_io_trace *t)
fb7b71a3
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62{
63 if (t->pdu_len == 0)
64 return 0;
65
bd6f78b2 66 dprint(FD_BLKTRACE, "discard pdu len %u\n", t->pdu_len);
f12b323f 67 return trace_fifo_get(td, fifo, fd, NULL, t->pdu_len);
fb7b71a3
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68}
69
8c1fdf04
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70/*
71 * Check if this is a blktrace binary data file. We read a single trace
72 * into memory and check for the magic signature.
73 */
fb7b71a3
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74int is_blktrace(const char *filename)
75{
76 struct blk_io_trace t;
77 int fd, ret;
78
79 fd = open(filename, O_RDONLY);
4dced407 80 if (fd < 0)
fb7b71a3 81 return 0;
fb7b71a3
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82
83 ret = read(fd, &t, sizeof(t));
84 close(fd);
85
86 if (ret < 0) {
87 perror("read blktrace");
88 return 0;
89 } else if (ret != sizeof(t)) {
90 log_err("fio: short read on blktrace file\n");
91 return 0;
92 }
93
94 if ((t.magic & 0xffffff00) == BLK_IO_TRACE_MAGIC)
95 return 1;
96
97 return 0;
98}
99
d1c46c04
DN
100static int lookup_device(struct thread_data *td, char *path, unsigned int maj,
101 unsigned int min)
5e6c2067
JA
102{
103 struct dirent *dir;
104 struct stat st;
105 int found = 0;
106 DIR *D;
107
108 D = opendir(path);
109 if (!D)
110 return 0;
111
112 while ((dir = readdir(D)) != NULL) {
113 char full_path[256];
114
115 if (!strcmp(dir->d_name, ".") || !strcmp(dir->d_name, ".."))
116 continue;
117
118 sprintf(full_path, "%s/%s", path, dir->d_name);
119 if (lstat(full_path, &st) == -1) {
120 perror("lstat");
121 break;
122 }
123
124 if (S_ISDIR(st.st_mode)) {
d1c46c04 125 found = lookup_device(td, full_path, maj, min);
5e6c2067
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126 if (found) {
127 strcpy(path, full_path);
128 break;
129 }
130 }
131
132 if (!S_ISBLK(st.st_mode))
133 continue;
134
d1c46c04
DN
135 /*
136 * If replay_redirect is set then always return this device
137 * upon lookup which overrides the device lookup based on
138 * major minor in the actual blktrace
139 */
140 if (td->o.replay_redirect) {
141 dprint(FD_BLKTRACE, "device lookup: %d/%d\n overridden"
142 " with: %s", maj, min,
143 td->o.replay_redirect);
144 strcpy(path, td->o.replay_redirect);
145 found = 1;
146 break;
147 }
148
5e6c2067 149 if (maj == major(st.st_rdev) && min == minor(st.st_rdev)) {
5ec10eaa 150 dprint(FD_BLKTRACE, "device lookup: %d/%d\n", maj, min);
5e6c2067
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151 strcpy(path, full_path);
152 found = 1;
153 break;
154 }
155 }
156
157 closedir(D);
158 return found;
159}
160
c69aa91f
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161#define FMINORBITS 20
162#define FMINORMASK ((1U << FMINORBITS) - 1)
163#define FMAJOR(dev) ((unsigned int) ((dev) >> FMINORBITS))
164#define FMINOR(dev) ((unsigned int) ((dev) & FMINORMASK))
eeb9c2aa 165
691c8fb0
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166static void trace_add_open_event(struct thread_data *td, int fileno)
167{
168 struct io_piece *ipo;
169
170 ipo = calloc(1, sizeof(*ipo));
171
172 ipo->ddir = DDIR_INVAL;
173 ipo->fileno = fileno;
174 ipo->file_action = FIO_LOG_OPEN_FILE;
01743ee1 175 flist_add_tail(&ipo->list, &td->io_log_list);
691c8fb0
JA
176}
177
5e6c2067
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178static void trace_add_file(struct thread_data *td, __u32 device)
179{
180 static unsigned int last_maj, last_min;
c69aa91f
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181 unsigned int maj = FMAJOR(device);
182 unsigned int min = FMINOR(device);
5e6c2067
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183 struct fio_file *f;
184 char dev[256];
185 unsigned int i;
186
187 if (last_maj == maj && last_min == min)
188 return;
189
190 last_maj = maj;
191 last_min = min;
192
193 /*
194 * check for this file in our list
195 */
196 for_each_file(td, f, i)
197 if (f->major == maj && f->minor == min)
198 return;
199
200 strcpy(dev, "/dev");
d1c46c04 201 if (lookup_device(td, dev, maj, min)) {
691c8fb0
JA
202 int fileno;
203
bd6f78b2 204 dprint(FD_BLKTRACE, "add devices %s\n", dev);
49ffb4a2 205 fileno = add_file_exclusive(td, dev);
691c8fb0 206 trace_add_open_event(td, fileno);
bd6f78b2 207 }
5e6c2067
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208}
209
8c1fdf04
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210/*
211 * Store blk_io_trace data in an ipo for later retrieval.
212 */
fdefd987 213static void store_ipo(struct thread_data *td, unsigned long long offset,
8c1fdf04 214 unsigned int bytes, int rw, unsigned long long ttime)
fdefd987
JA
215{
216 struct io_piece *ipo = malloc(sizeof(*ipo));
217
218 memset(ipo, 0, sizeof(*ipo));
01743ee1 219 INIT_FLIST_HEAD(&ipo->list);
a2eea81b
JA
220 /*
221 * the 512 is wrong here, it should be the hardware sector size...
222 */
223 ipo->offset = offset * 512;
fdefd987 224 ipo->len = bytes;
8c1fdf04 225 ipo->delay = ttime / 1000;
fdefd987
JA
226 if (rw)
227 ipo->ddir = DDIR_WRITE;
228 else
229 ipo->ddir = DDIR_READ;
230
bd6f78b2
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231 dprint(FD_BLKTRACE, "store ddir=%d, off=%llu, len=%lu, delay=%lu\n",
232 ipo->ddir, ipo->offset,
233 ipo->len, ipo->delay);
691c8fb0 234 queue_io_piece(td, ipo);
fdefd987
JA
235}
236
0b9d69ec 237static void handle_trace_notify(struct blk_io_trace *t)
cd991b9e 238{
691c8fb0
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239 switch (t->action) {
240 case BLK_TN_PROCESS:
241 printf("got process notify: %x, %d\n", t->action, t->pid);
242 break;
243 case BLK_TN_TIMESTAMP:
244 printf("got timestamp notify: %x, %d\n", t->action, t->pid);
245 break;
ff58fced
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246 case BLK_TN_MESSAGE:
247 break;
691c8fb0
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248 default:
249 dprint(FD_BLKTRACE, "unknown trace act %x\n", t->action);
250 break;
251 }
252}
5b3023b8 253
ff58fced
JA
254static void handle_trace_discard(struct thread_data *td, struct blk_io_trace *t,
255 unsigned long long ttime, unsigned long *ios)
256{
257 struct io_piece *ipo = malloc(sizeof(*ipo));
258
259 trace_add_file(td, t->device);
260
261 ios[DDIR_WRITE]++;
262 td->o.size += t->bytes;
263
264 memset(ipo, 0, sizeof(*ipo));
265 INIT_FLIST_HEAD(&ipo->list);
266
267 /*
268 * the 512 is wrong here, it should be the hardware sector size...
269 */
270 ipo->offset = t->sector * 512;
271 ipo->len = t->bytes;
272 ipo->delay = ttime / 1000;
273 ipo->ddir = DDIR_TRIM;
274
275 dprint(FD_BLKTRACE, "store discard, off=%llu, len=%lu, delay=%lu\n",
276 ipo->offset, ipo->len,
277 ipo->delay);
278 queue_io_piece(td, ipo);
279}
280
691c8fb0
JA
281static void handle_trace_fs(struct thread_data *td, struct blk_io_trace *t,
282 unsigned long long ttime, unsigned long *ios,
283 unsigned int *bs)
284{
285 int rw;
5b3023b8
JA
286
287 trace_add_file(td, t->device);
288
289 rw = (t->action & BLK_TC_ACT(BLK_TC_WRITE)) != 0;
290
291 if (t->bytes > bs[rw])
292 bs[rw] = t->bytes;
293
294 ios[rw]++;
295 td->o.size += t->bytes;
296 store_ipo(td, t->sector, t->bytes, rw, ttime);
cd991b9e
JA
297}
298
691c8fb0
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299/*
300 * We only care for queue traces, most of the others are side effects
301 * due to internal workings of the block layer.
302 */
303static void handle_trace(struct thread_data *td, struct blk_io_trace *t,
304 unsigned long long ttime, unsigned long *ios,
305 unsigned int *bs)
306{
307 if ((t->action & 0xffff) != __BLK_TA_QUEUE)
308 return;
309 if (t->action & BLK_TC_ACT(BLK_TC_PC))
310 return;
311
312 if (t->action & BLK_TC_ACT(BLK_TC_NOTIFY))
aec2de20 313 handle_trace_notify(t);
ff58fced
JA
314 else if (t->action & BLK_TC_ACT(BLK_TC_DISCARD))
315 handle_trace_discard(td, t, ttime, ios);
691c8fb0
JA
316 else
317 handle_trace_fs(td, t, ttime, ios, bs);
318}
319
8c1fdf04
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320/*
321 * Load a blktrace file by reading all the blk_io_trace entries, and storing
322 * them as io_pieces like the fio text version would do.
323 */
fb7b71a3
JA
324int load_blktrace(struct thread_data *td, const char *filename)
325{
a61eddec 326 unsigned long long ttime, delay;
fb7b71a3 327 struct blk_io_trace t;
4241ea8f 328 unsigned long ios[2], skipped_writes;
a61eddec 329 unsigned int cpu;
d84f8d49 330 unsigned int rw_bs[2];
e2887563 331 struct fifo *fifo;
fb7b71a3
JA
332 int fd;
333
334 fd = open(filename, O_RDONLY);
335 if (fd < 0) {
336 td_verror(td, errno, "open blktrace file");
337 return 1;
338 }
339
e2887563
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340 fifo = fifo_alloc(TRACE_FIFO_SIZE);
341
6df8adaa
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342 td->o.size = 0;
343
a61eddec 344 cpu = 0;
d84f8d49
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345 ttime = 0;
346 ios[0] = ios[1] = 0;
347 rw_bs[0] = rw_bs[1] = 0;
4241ea8f 348 skipped_writes = 0;
fb7b71a3 349 do {
e2887563 350 int ret = trace_fifo_get(td, fifo, fd, &t, sizeof(t));
fb7b71a3 351
e2887563 352 if (ret < 0)
8c1fdf04 353 goto err;
e2887563
JA
354 else if (!ret)
355 break;
356 else if (ret < (int) sizeof(t)) {
357 log_err("fio: short fifo get\n");
fb7b71a3 358 break;
fb7b71a3
JA
359 }
360
361 if ((t.magic & 0xffffff00) != BLK_IO_TRACE_MAGIC) {
5ec10eaa
JA
362 log_err("fio: bad magic in blktrace data: %x\n",
363 t.magic);
8c1fdf04 364 goto err;
fb7b71a3
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365 }
366 if ((t.magic & 0xff) != BLK_IO_TRACE_VERSION) {
5ec10eaa
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367 log_err("fio: bad blktrace version %d\n",
368 t.magic & 0xff);
8c1fdf04 369 goto err;
fb7b71a3 370 }
f12b323f
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371 ret = discard_pdu(td, fifo, fd, &t);
372 if (ret < 0) {
fb7b71a3 373 td_verror(td, ret, "blktrace lseek");
8c1fdf04 374 goto err;
f12b323f
JA
375 } else if (t.pdu_len != ret) {
376 log_err("fio: discarded %d of %d\n", ret, t.pdu_len);
377 goto err;
fb7b71a3 378 }
691c8fb0
JA
379 if ((t.action & BLK_TC_ACT(BLK_TC_NOTIFY)) == 0) {
380 if (!ttime) {
381 ttime = t.time;
382 cpu = t.cpu;
383 }
384
385 delay = 0;
386 if (cpu == t.cpu)
387 delay = t.time - ttime;
388 if ((t.action & BLK_TC_ACT(BLK_TC_WRITE)) && read_only)
389 skipped_writes++;
64bbb865
DN
390 else {
391 /*
392 * set delay to zero if no_stall enabled for
393 * fast replay
394 */
395 if (td->o.no_stall)
396 delay = 0;
397
691c8fb0 398 handle_trace(td, &t, delay, ios, rw_bs);
64bbb865 399 }
691c8fb0 400
8c1fdf04 401 ttime = t.time;
a61eddec 402 cpu = t.cpu;
a6edd638
JA
403 } else {
404 delay = 0;
4241ea8f 405 handle_trace(td, &t, delay, ios, rw_bs);
a6edd638 406 }
fb7b71a3
JA
407 } while (1);
408
38470f85 409 fifo_free(fifo);
fb7b71a3 410 close(fd);
8c1fdf04 411
4241ea8f 412 if (skipped_writes)
5ec10eaa
JA
413 log_err("fio: %s skips replay of %lu writes due to read-only\n",
414 td->o.name, skipped_writes);
4241ea8f 415
8c1fdf04
JA
416 if (!ios[DDIR_READ] && !ios[DDIR_WRITE]) {
417 log_err("fio: found no ios in blktrace data\n");
418 return 1;
d84f8d49 419 } else if (ios[DDIR_READ] && !ios[DDIR_READ]) {
8c1fdf04 420 td->o.td_ddir = TD_DDIR_READ;
d84f8d49
JA
421 td->o.max_bs[DDIR_READ] = rw_bs[DDIR_READ];
422 } else if (!ios[DDIR_READ] && ios[DDIR_WRITE]) {
8c1fdf04 423 td->o.td_ddir = TD_DDIR_WRITE;
d84f8d49
JA
424 td->o.max_bs[DDIR_WRITE] = rw_bs[DDIR_WRITE];
425 } else {
8c1fdf04 426 td->o.td_ddir = TD_DDIR_RW;
d84f8d49
JA
427 td->o.max_bs[DDIR_READ] = rw_bs[DDIR_READ];
428 td->o.max_bs[DDIR_WRITE] = rw_bs[DDIR_WRITE];
429 }
8c1fdf04
JA
430
431 /*
432 * We need to do direct/raw ios to the device, to avoid getting
433 * read-ahead in our way.
434 */
435 td->o.odirect = 1;
436
fb7b71a3 437 return 0;
8c1fdf04
JA
438err:
439 close(fd);
38470f85 440 fifo_free(fifo);
8c1fdf04 441 return 1;
fb7b71a3 442}