Make SH port work for packagers that don't differentiate between SH4 and SH4A
[fio.git] / blktrace.c
1 /*
2  * blktrace support code for fio
3  */
4 #include <stdio.h>
5 #include <stdlib.h>
6 #include <sys/stat.h>
7 #include <dirent.h>
8
9 #include "flist.h"
10 #include "fio.h"
11 #include "blktrace_api.h"
12
13 #define TRACE_FIFO_SIZE 8192
14
15 /*
16  * fifo refill frontend, to avoid reading data in trace sized bites
17  */
18 static int refill_fifo(struct thread_data *td, struct fifo *fifo, int fd)
19 {
20         char buf[TRACE_FIFO_SIZE];
21         unsigned int total;
22         int ret;
23
24         total = sizeof(buf);
25         if (total > fifo_room(fifo))
26                 total = fifo_room(fifo);
27
28         ret = read(fd, buf, total);
29         if (ret < 0) {
30                 td_verror(td, errno, "read blktrace file");
31                 return -1;
32         }
33
34         if (ret > 0)
35                 ret = fifo_put(fifo, buf, ret);
36
37         dprint(FD_BLKTRACE, "refill: filled %d bytes\n", ret);
38         return ret;
39 }
40
41 /*
42  * Retrieve 'len' bytes from the fifo, refilling if necessary.
43  */
44 static int trace_fifo_get(struct thread_data *td, struct fifo *fifo, int fd,
45                           void *buf, unsigned int len)
46 {
47         if (fifo_len(fifo) < len) {
48                 int ret = refill_fifo(td, fifo, fd);
49
50                 if (ret < 0)
51                         return ret;
52         }
53
54         return fifo_get(fifo, buf, len);
55 }
56
57 /*
58  * Just discard the pdu by seeking past it.
59  */
60 static int discard_pdu(struct thread_data *td, struct fifo *fifo, int fd,
61                        struct blk_io_trace *t)
62 {
63         if (t->pdu_len == 0)
64                 return 0;
65
66         dprint(FD_BLKTRACE, "discard pdu len %u\n", t->pdu_len);
67         return trace_fifo_get(td, fifo, fd, NULL, t->pdu_len);
68 }
69
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  */
74 int is_blktrace(const char *filename)
75 {
76         struct blk_io_trace t;
77         int fd, ret;
78
79         fd = open(filename, O_RDONLY);
80         if (fd < 0)
81                 return 0;
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
100 static int lookup_device(struct thread_data *td, char *path, unsigned int maj,
101                          unsigned int min)
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)) {
125                         found = lookup_device(td, full_path, maj, min);
126                         if (found) {
127                                 strcpy(path, full_path);
128                                 break;
129                         }
130                 }
131
132                 if (!S_ISBLK(st.st_mode))
133                         continue;
134
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
149                 if (maj == major(st.st_rdev) && min == minor(st.st_rdev)) {
150                         dprint(FD_BLKTRACE, "device lookup: %d/%d\n", maj, min);
151                         strcpy(path, full_path);
152                         found = 1;
153                         break;
154                 }
155         }
156
157         closedir(D);
158         return found;
159 }
160
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))
165
166 static 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         init_ipo(ipo);
172
173         ipo->ddir = DDIR_INVAL;
174         ipo->fileno = fileno;
175         ipo->file_action = FIO_LOG_OPEN_FILE;
176         flist_add_tail(&ipo->list, &td->io_log_list);
177 }
178
179 static void trace_add_file(struct thread_data *td, __u32 device)
180 {
181         static unsigned int last_maj, last_min;
182         unsigned int maj = FMAJOR(device);
183         unsigned int min = FMINOR(device);
184         struct fio_file *f;
185         char dev[256];
186         unsigned int i;
187
188         if (last_maj == maj && last_min == min)
189                 return;
190
191         last_maj = maj;
192         last_min = min;
193
194         /*
195          * check for this file in our list
196          */
197         for_each_file(td, f, i)
198                 if (f->major == maj && f->minor == min)
199                         return;
200
201         strcpy(dev, "/dev");
202         if (lookup_device(td, dev, maj, min)) {
203                 int fileno;
204
205                 dprint(FD_BLKTRACE, "add devices %s\n", dev);
206                 fileno = add_file_exclusive(td, dev);
207                 trace_add_open_event(td, fileno);
208         }
209 }
210
211 /*
212  * Store blk_io_trace data in an ipo for later retrieval.
213  */
214 static void store_ipo(struct thread_data *td, unsigned long long offset,
215                       unsigned int bytes, int rw, unsigned long long ttime)
216 {
217         struct io_piece *ipo = malloc(sizeof(*ipo));
218
219         init_ipo(ipo);
220
221         /*
222          * the 512 is wrong here, it should be the hardware sector size...
223          */
224         ipo->offset = offset * 512;
225         ipo->len = bytes;
226         ipo->delay = ttime / 1000;
227         if (rw)
228                 ipo->ddir = DDIR_WRITE;
229         else
230                 ipo->ddir = DDIR_READ;
231
232         dprint(FD_BLKTRACE, "store ddir=%d, off=%llu, len=%lu, delay=%lu\n",
233                                                         ipo->ddir, ipo->offset,
234                                                         ipo->len, ipo->delay);
235         queue_io_piece(td, ipo);
236 }
237
238 static void handle_trace_notify(struct blk_io_trace *t)
239 {
240         switch (t->action) {
241         case BLK_TN_PROCESS:
242                 printf("got process notify: %x, %d\n", t->action, t->pid);
243                 break;
244         case BLK_TN_TIMESTAMP:
245                 printf("got timestamp notify: %x, %d\n", t->action, t->pid);
246                 break;
247         case BLK_TN_MESSAGE:
248                 break;
249         default:
250                 dprint(FD_BLKTRACE, "unknown trace act %x\n", t->action);
251                 break;
252         }
253 }
254
255 static void handle_trace_discard(struct thread_data *td, struct blk_io_trace *t,
256                                  unsigned long long ttime, unsigned long *ios)
257 {
258         struct io_piece *ipo = malloc(sizeof(*ipo));
259
260         init_ipo(ipo);
261         trace_add_file(td, t->device);
262
263         ios[DDIR_WRITE]++;
264         td->o.size += t->bytes;
265
266         memset(ipo, 0, sizeof(*ipo));
267         INIT_FLIST_HEAD(&ipo->list);
268
269         /*
270          * the 512 is wrong here, it should be the hardware sector size...
271          */
272         ipo->offset = t->sector * 512;
273         ipo->len = t->bytes;
274         ipo->delay = ttime / 1000;
275         ipo->ddir = DDIR_TRIM;
276
277         dprint(FD_BLKTRACE, "store discard, off=%llu, len=%lu, delay=%lu\n",
278                                                         ipo->offset, ipo->len,
279                                                         ipo->delay);
280         queue_io_piece(td, ipo);
281 }
282
283 static void handle_trace_fs(struct thread_data *td, struct blk_io_trace *t,
284                             unsigned long long ttime, unsigned long *ios,
285                             unsigned int *bs)
286 {
287         int rw;
288
289         trace_add_file(td, t->device);
290
291         rw = (t->action & BLK_TC_ACT(BLK_TC_WRITE)) != 0;
292
293         if (t->bytes > bs[rw])
294                 bs[rw] = t->bytes;
295
296         ios[rw]++;
297         td->o.size += t->bytes;
298         store_ipo(td, t->sector, t->bytes, rw, ttime);
299 }
300
301 /*
302  * We only care for queue traces, most of the others are side effects
303  * due to internal workings of the block layer.
304  */
305 static void handle_trace(struct thread_data *td, struct blk_io_trace *t,
306                          unsigned long long ttime, unsigned long *ios,
307                          unsigned int *bs)
308 {
309         if ((t->action & 0xffff) != __BLK_TA_QUEUE)
310                 return;
311         if (t->action & BLK_TC_ACT(BLK_TC_PC))
312                 return;
313
314         if (t->action & BLK_TC_ACT(BLK_TC_NOTIFY))
315                 handle_trace_notify(t);
316         else if (t->action & BLK_TC_ACT(BLK_TC_DISCARD))
317                 handle_trace_discard(td, t, ttime, ios);
318         else
319                 handle_trace_fs(td, t, ttime, ios, bs);
320 }
321
322 /*
323  * Load a blktrace file by reading all the blk_io_trace entries, and storing
324  * them as io_pieces like the fio text version would do.
325  */
326 int load_blktrace(struct thread_data *td, const char *filename)
327 {
328         unsigned long long ttime, delay;
329         struct blk_io_trace t;
330         unsigned long ios[2], skipped_writes;
331         unsigned int cpu;
332         unsigned int rw_bs[2];
333         struct fifo *fifo;
334         int fd;
335
336         fd = open(filename, O_RDONLY);
337         if (fd < 0) {
338                 td_verror(td, errno, "open blktrace file");
339                 return 1;
340         }
341
342         fifo = fifo_alloc(TRACE_FIFO_SIZE);
343
344         td->o.size = 0;
345
346         cpu = 0;
347         ttime = 0;
348         ios[0] = ios[1] = 0;
349         rw_bs[0] = rw_bs[1] = 0;
350         skipped_writes = 0;
351         do {
352                 int ret = trace_fifo_get(td, fifo, fd, &t, sizeof(t));
353
354                 if (ret < 0)
355                         goto err;
356                 else if (!ret)
357                         break;
358                 else if (ret < (int) sizeof(t)) {
359                         log_err("fio: short fifo get\n");
360                         break;
361                 }
362
363                 if ((t.magic & 0xffffff00) != BLK_IO_TRACE_MAGIC) {
364                         log_err("fio: bad magic in blktrace data: %x\n",
365                                                                 t.magic);
366                         goto err;
367                 }
368                 if ((t.magic & 0xff) != BLK_IO_TRACE_VERSION) {
369                         log_err("fio: bad blktrace version %d\n",
370                                                                 t.magic & 0xff);
371                         goto err;
372                 }
373                 ret = discard_pdu(td, fifo, fd, &t);
374                 if (ret < 0) {
375                         td_verror(td, ret, "blktrace lseek");
376                         goto err;
377                 } else if (t.pdu_len != ret) {
378                         log_err("fio: discarded %d of %d\n", ret, t.pdu_len);
379                         goto err;
380                 }
381                 if ((t.action & BLK_TC_ACT(BLK_TC_NOTIFY)) == 0) {
382                         if (!ttime) {
383                                 ttime = t.time;
384                                 cpu = t.cpu;
385                         }
386
387                         delay = 0;
388                         if (cpu == t.cpu)
389                                 delay = t.time - ttime;
390                         if ((t.action & BLK_TC_ACT(BLK_TC_WRITE)) && read_only)
391                                 skipped_writes++;
392                         else {
393                                 /*
394                                  * set delay to zero if no_stall enabled for
395                                  * fast replay
396                                  */
397                                 if (td->o.no_stall)
398                                         delay = 0;
399
400                                 handle_trace(td, &t, delay, ios, rw_bs);
401                         }
402
403                         ttime = t.time;
404                         cpu = t.cpu;
405                 } else {
406                         delay = 0;
407                         handle_trace(td, &t, delay, ios, rw_bs);
408                 }
409         } while (1);
410
411         fifo_free(fifo);
412         close(fd);
413
414         if (skipped_writes)
415                 log_err("fio: %s skips replay of %lu writes due to read-only\n",
416                                                 td->o.name, skipped_writes);
417
418         if (!ios[DDIR_READ] && !ios[DDIR_WRITE]) {
419                 log_err("fio: found no ios in blktrace data\n");
420                 return 1;
421         } else if (ios[DDIR_READ] && !ios[DDIR_READ]) {
422                 td->o.td_ddir = TD_DDIR_READ;
423                 td->o.max_bs[DDIR_READ] = rw_bs[DDIR_READ];
424         } else if (!ios[DDIR_READ] && ios[DDIR_WRITE]) {
425                 td->o.td_ddir = TD_DDIR_WRITE;
426                 td->o.max_bs[DDIR_WRITE] = rw_bs[DDIR_WRITE];
427         } else {
428                 td->o.td_ddir = TD_DDIR_RW;
429                 td->o.max_bs[DDIR_READ] = rw_bs[DDIR_READ];
430                 td->o.max_bs[DDIR_WRITE] = rw_bs[DDIR_WRITE];
431         }
432
433         /*
434          * We need to do direct/raw ios to the device, to avoid getting
435          * read-ahead in our way.
436          */
437         td->o.odirect = 1;
438
439         return 0;
440 err:
441         close(fd);
442         fifo_free(fifo);
443         return 1;
444 }