617de8e1 |
1 | /* lttd |
2 | * |
3 | * Linux Trace Toolkit Daemon |
4 | * |
c2ffa20f |
5 | * This is a simple daemon that reads a few relay+debugfs channels and save |
6 | * them in a trace. |
617de8e1 |
7 | * |
8 | * |
9 | * Copyright 2005 - |
10 | * Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> |
11 | */ |
12 | |
0bb647f5 |
13 | #ifdef HAVE_CONFIG_H |
469206ed |
14 | #include <config.h> |
0bb647f5 |
15 | #endif |
16 | |
e54e1d5d |
17 | #define _REENTRANT |
0bb647f5 |
18 | #define _GNU_SOURCE |
e54e1d5d |
19 | #include <features.h> |
617de8e1 |
20 | #include <stdio.h> |
1d483eea |
21 | #include <unistd.h> |
617de8e1 |
22 | #include <errno.h> |
23 | #include <sys/types.h> |
24 | #include <sys/stat.h> |
617de8e1 |
25 | #include <stdlib.h> |
26 | #include <dirent.h> |
27 | #include <string.h> |
90ccaa9a |
28 | #include <fcntl.h> |
29 | #include <sys/poll.h> |
1d483eea |
30 | #include <sys/mman.h> |
31 | #include <signal.h> |
e54e1d5d |
32 | #include <pthread.h> |
357915bb |
33 | #include <sys/syscall.h> |
34 | #include <unistd.h> |
35 | #include <asm/ioctls.h> |
36 | |
37 | #include <linux/version.h> |
1d483eea |
38 | |
39 | /* Relayfs IOCTL */ |
40 | #include <asm/ioctl.h> |
41 | #include <asm/types.h> |
42 | |
43 | /* Get the next sub buffer that can be read. */ |
766632ac |
44 | #define RELAY_GET_SUBBUF _IOR(0xF5, 0x00,__u32) |
1d483eea |
45 | /* Release the oldest reserved (by "get") sub buffer. */ |
766632ac |
46 | #define RELAY_PUT_SUBBUF _IOW(0xF5, 0x01,__u32) |
1d483eea |
47 | /* returns the number of sub buffers in the per cpu channel. */ |
766632ac |
48 | #define RELAY_GET_N_SUBBUFS _IOR(0xF5, 0x02,__u32) |
1d483eea |
49 | /* returns the size of the sub buffers. */ |
766632ac |
50 | #define RELAY_GET_SUBBUF_SIZE _IOR(0xF5, 0x03,__u32) |
1d483eea |
51 | |
357915bb |
52 | #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,14) |
53 | #include <linux/inotify.h> |
54 | /* From the inotify-tools 2.6 package */ |
55 | static inline int inotify_init (void) |
56 | { |
57 | return syscall (__NR_inotify_init); |
58 | } |
59 | |
60 | static inline int inotify_add_watch (int fd, const char *name, __u32 mask) |
61 | { |
62 | return syscall (__NR_inotify_add_watch, fd, name, mask); |
63 | } |
64 | |
65 | static inline int inotify_rm_watch (int fd, __u32 wd) |
66 | { |
67 | return syscall (__NR_inotify_rm_watch, fd, wd); |
68 | } |
69 | #define HAS_INOTIFY |
70 | #else |
71 | static inline int inotify_init (void) |
72 | { |
73 | return -1; |
74 | } |
1d483eea |
75 | |
357915bb |
76 | static inline int inotify_add_watch (int fd, const char *name, __u32 mask) |
77 | { |
78 | return 0; |
79 | } |
80 | |
81 | static inline int inotify_rm_watch (int fd, __u32 wd) |
82 | { |
83 | return 0; |
84 | } |
85 | #undef HAS_INOTIFY |
86 | #endif |
617de8e1 |
87 | |
88 | enum { |
89 | GET_SUBBUF, |
90 | PUT_SUBBUF, |
91 | GET_N_BUBBUFS, |
92 | GET_SUBBUF_SIZE |
93 | }; |
94 | |
95 | struct fd_pair { |
96 | int channel; |
97 | int trace; |
1d483eea |
98 | unsigned int n_subbufs; |
99 | unsigned int subbuf_size; |
100 | void *mmap; |
5ffb77aa |
101 | pthread_mutex_t mutex; |
617de8e1 |
102 | }; |
103 | |
104 | struct channel_trace_fd { |
105 | struct fd_pair *pair; |
106 | int num_pairs; |
107 | }; |
108 | |
357915bb |
109 | struct inotify_watch { |
110 | int wd; |
111 | char path_channel[PATH_MAX]; |
112 | char path_trace[PATH_MAX]; |
113 | }; |
114 | |
115 | struct inotify_watch_array { |
116 | struct inotify_watch *elem; |
117 | int num; |
118 | }; |
119 | |
89565b43 |
120 | static char *trace_name = NULL; |
121 | static char *channel_name = NULL; |
122 | static int daemon_mode = 0; |
123 | static int append_mode = 0; |
124 | static unsigned long num_threads = 1; |
1d483eea |
125 | volatile static int quit_program = 0; /* For signal handler */ |
89565b43 |
126 | static int dump_flight_only = 0; |
127 | static int dump_normal_only = 0; |
617de8e1 |
128 | |
129 | /* Args : |
130 | * |
131 | * -t directory Directory name of the trace to write to. Will be created. |
c2ffa20f |
132 | * -c directory Root directory of the debugfs trace channels. |
617de8e1 |
133 | * -d Run in background (daemon). |
90ccaa9a |
134 | * -a Trace append mode. |
ce2b5176 |
135 | * -s Send SIGUSR1 to parent when ready for IO. |
617de8e1 |
136 | */ |
137 | void show_arguments(void) |
138 | { |
139 | printf("Please use the following arguments :\n"); |
140 | printf("\n"); |
141 | printf("-t directory Directory name of the trace to write to.\n" |
142 | " It will be created.\n"); |
c2ffa20f |
143 | printf("-c directory Root directory of the debugfs trace channels.\n"); |
617de8e1 |
144 | printf("-d Run in background (daemon).\n"); |
90ccaa9a |
145 | printf("-a Append to an possibly existing trace.\n"); |
5ffb77aa |
146 | printf("-N Number of threads to start.\n"); |
89565b43 |
147 | printf("-f Dump only flight recorder channels.\n"); |
148 | printf("-n Dump only normal channels.\n"); |
617de8e1 |
149 | printf("\n"); |
150 | } |
151 | |
152 | |
153 | /* parse_arguments |
154 | * |
155 | * Parses the command line arguments. |
156 | * |
157 | * Returns 1 if the arguments were correct, but doesn't ask for program |
158 | * continuation. Returns -1 if the arguments are incorrect, or 0 if OK. |
159 | */ |
160 | int parse_arguments(int argc, char **argv) |
161 | { |
162 | int ret = 0; |
163 | int argn = 1; |
164 | |
165 | if(argc == 2) { |
166 | if(strcmp(argv[1], "-h") == 0) { |
167 | return 1; |
168 | } |
169 | } |
170 | |
90ccaa9a |
171 | while(argn < argc) { |
617de8e1 |
172 | |
173 | switch(argv[argn][0]) { |
174 | case '-': |
175 | switch(argv[argn][1]) { |
176 | case 't': |
90ccaa9a |
177 | if(argn+1 < argc) { |
178 | trace_name = argv[argn+1]; |
179 | argn++; |
180 | } |
617de8e1 |
181 | break; |
182 | case 'c': |
90ccaa9a |
183 | if(argn+1 < argc) { |
184 | channel_name = argv[argn+1]; |
185 | argn++; |
186 | } |
617de8e1 |
187 | break; |
188 | case 'd': |
189 | daemon_mode = 1; |
190 | break; |
90ccaa9a |
191 | case 'a': |
192 | append_mode = 1; |
193 | break; |
5ffb77aa |
194 | case 'N': |
e54e1d5d |
195 | if(argn+1 < argc) { |
196 | num_threads = strtoul(argv[argn+1], NULL, 0); |
197 | argn++; |
198 | } |
199 | break; |
89565b43 |
200 | case 'f': |
201 | dump_flight_only = 1; |
202 | break; |
203 | case 'n': |
204 | dump_normal_only = 1; |
205 | break; |
617de8e1 |
206 | default: |
207 | printf("Invalid argument '%s'.\n", argv[argn]); |
208 | printf("\n"); |
209 | ret = -1; |
210 | } |
211 | break; |
212 | default: |
213 | printf("Invalid argument '%s'.\n", argv[argn]); |
214 | printf("\n"); |
215 | ret = -1; |
216 | } |
217 | argn++; |
218 | } |
219 | |
220 | if(trace_name == NULL) { |
221 | printf("Please specify a trace name.\n"); |
222 | printf("\n"); |
223 | ret = -1; |
224 | } |
225 | |
226 | if(channel_name == NULL) { |
227 | printf("Please specify a channel name.\n"); |
228 | printf("\n"); |
229 | ret = -1; |
230 | } |
231 | |
232 | return ret; |
233 | } |
234 | |
235 | void show_info(void) |
236 | { |
15061ecb |
237 | printf("Linux Trace Toolkit Trace Daemon " VERSION "\n"); |
617de8e1 |
238 | printf("\n"); |
c2ffa20f |
239 | printf("Reading from debugfs directory : %s\n", channel_name); |
617de8e1 |
240 | printf("Writing to trace directory : %s\n", trace_name); |
241 | printf("\n"); |
242 | } |
243 | |
244 | |
1d483eea |
245 | /* signal handling */ |
246 | |
247 | static void handler(int signo) |
248 | { |
249 | printf("Signal %d received : exiting cleanly\n", signo); |
250 | quit_program = 1; |
251 | } |
252 | |
253 | |
357915bb |
254 | int open_buffer_file(char *filename, char *path_channel, char *path_trace, |
255 | struct channel_trace_fd *fd_pairs) |
256 | { |
257 | int open_ret = 0; |
258 | int ret = 0; |
259 | struct stat stat_buf; |
260 | |
261 | if(strncmp(filename, "flight-", sizeof("flight-")-1) != 0) { |
262 | if(dump_flight_only) { |
263 | printf("Skipping normal channel %s\n", path_channel); |
264 | return 0; |
265 | } |
266 | } else { |
267 | if(dump_normal_only) { |
268 | printf("Skipping flight channel %s\n", path_channel); |
269 | return 0; |
270 | } |
271 | } |
272 | printf("Opening file.\n"); |
273 | |
274 | fd_pairs->pair = realloc(fd_pairs->pair, |
275 | ++fd_pairs->num_pairs * sizeof(struct fd_pair)); |
276 | |
277 | /* Open the channel in read mode */ |
278 | fd_pairs->pair[fd_pairs->num_pairs-1].channel = |
279 | open(path_channel, O_RDONLY | O_NONBLOCK); |
280 | if(fd_pairs->pair[fd_pairs->num_pairs-1].channel == -1) { |
281 | perror(path_channel); |
282 | fd_pairs->num_pairs--; |
283 | return 0; /* continue */ |
284 | } |
285 | /* Open the trace in write mode, only append if append_mode */ |
286 | ret = stat(path_trace, &stat_buf); |
287 | if(ret == 0) { |
288 | if(append_mode) { |
289 | printf("Appending to file %s as requested\n", path_trace); |
290 | |
291 | fd_pairs->pair[fd_pairs->num_pairs-1].trace = |
292 | open(path_trace, O_WRONLY|O_APPEND, |
293 | S_IRWXU|S_IRWXG|S_IRWXO); |
294 | |
295 | if(fd_pairs->pair[fd_pairs->num_pairs-1].trace == -1) { |
296 | perror(path_trace); |
297 | } |
298 | } else { |
299 | printf("File %s exists, cannot open. Try append mode.\n", path_trace); |
300 | open_ret = -1; |
301 | goto end; |
302 | } |
303 | } else { |
304 | if(errno == ENOENT) { |
305 | fd_pairs->pair[fd_pairs->num_pairs-1].trace = |
306 | open(path_trace, O_WRONLY|O_CREAT|O_EXCL, |
307 | S_IRWXU|S_IRWXG|S_IRWXO); |
308 | if(fd_pairs->pair[fd_pairs->num_pairs-1].trace == -1) { |
309 | perror(path_trace); |
310 | } |
311 | } |
312 | } |
313 | end: |
314 | return open_ret; |
315 | } |
1d483eea |
316 | |
617de8e1 |
317 | int open_channel_trace_pairs(char *subchannel_name, char *subtrace_name, |
357915bb |
318 | struct channel_trace_fd *fd_pairs, int *inotify_fd, |
319 | struct inotify_watch_array *iwatch_array) |
617de8e1 |
320 | { |
321 | DIR *channel_dir = opendir(subchannel_name); |
322 | struct dirent *entry; |
323 | struct stat stat_buf; |
324 | int ret; |
325 | char path_channel[PATH_MAX]; |
326 | int path_channel_len; |
327 | char *path_channel_ptr; |
328 | char path_trace[PATH_MAX]; |
329 | int path_trace_len; |
330 | char *path_trace_ptr; |
002f91bb |
331 | int open_ret = 0; |
617de8e1 |
332 | |
333 | if(channel_dir == NULL) { |
334 | perror(subchannel_name); |
d304b1dd |
335 | open_ret = ENOENT; |
002f91bb |
336 | goto end; |
617de8e1 |
337 | } |
338 | |
617de8e1 |
339 | printf("Creating trace subdirectory %s\n", subtrace_name); |
340 | ret = mkdir(subtrace_name, S_IRWXU|S_IRWXG|S_IRWXO); |
341 | if(ret == -1) { |
b1e3e7c7 |
342 | if(errno != EEXIST) { |
90ccaa9a |
343 | perror(subtrace_name); |
002f91bb |
344 | open_ret = -1; |
d304b1dd |
345 | goto end; |
90ccaa9a |
346 | } |
617de8e1 |
347 | } |
348 | |
349 | strncpy(path_channel, subchannel_name, PATH_MAX-1); |
350 | path_channel_len = strlen(path_channel); |
351 | path_channel[path_channel_len] = '/'; |
352 | path_channel_len++; |
353 | path_channel_ptr = path_channel + path_channel_len; |
354 | |
355 | strncpy(path_trace, subtrace_name, PATH_MAX-1); |
356 | path_trace_len = strlen(path_trace); |
357 | path_trace[path_trace_len] = '/'; |
358 | path_trace_len++; |
359 | path_trace_ptr = path_trace + path_trace_len; |
360 | |
357915bb |
361 | #ifdef HAS_INOTIFY |
362 | iwatch_array->elem = realloc(iwatch_array->elem, |
363 | ++iwatch_array->num * sizeof(struct inotify_watch)); |
364 | |
365 | printf("Adding inotify for channel %s\n", path_channel); |
366 | iwatch_array->elem[iwatch_array->num-1].wd = inotify_add_watch(*inotify_fd, path_channel, IN_CREATE); |
367 | strcpy(iwatch_array->elem[iwatch_array->num-1].path_channel, path_channel); |
368 | strcpy(iwatch_array->elem[iwatch_array->num-1].path_trace, path_trace); |
369 | printf("Added inotify for channel %s, wd %u\n", iwatch_array->elem[iwatch_array->num-1].path_channel, |
370 | iwatch_array->elem[iwatch_array->num-1].wd); |
371 | #endif |
372 | |
617de8e1 |
373 | while((entry = readdir(channel_dir)) != NULL) { |
374 | |
375 | if(entry->d_name[0] == '.') continue; |
376 | |
377 | strncpy(path_channel_ptr, entry->d_name, PATH_MAX - path_channel_len); |
378 | strncpy(path_trace_ptr, entry->d_name, PATH_MAX - path_trace_len); |
379 | |
380 | ret = stat(path_channel, &stat_buf); |
381 | if(ret == -1) { |
382 | perror(path_channel); |
383 | continue; |
384 | } |
385 | |
386 | printf("Channel file : %s\n", path_channel); |
387 | |
388 | if(S_ISDIR(stat_buf.st_mode)) { |
389 | |
390 | printf("Entering channel subdirectory...\n"); |
357915bb |
391 | ret = open_channel_trace_pairs(path_channel, path_trace, fd_pairs, |
392 | inotify_fd, iwatch_array); |
617de8e1 |
393 | if(ret < 0) continue; |
90ccaa9a |
394 | } else if(S_ISREG(stat_buf.st_mode)) { |
357915bb |
395 | open_ret = open_buffer_file(entry->d_name, path_channel, path_trace, |
396 | fd_pairs); |
397 | if(open_ret) |
398 | goto end; |
617de8e1 |
399 | } |
617de8e1 |
400 | } |
401 | |
d304b1dd |
402 | end: |
617de8e1 |
403 | closedir(channel_dir); |
404 | |
d304b1dd |
405 | return open_ret; |
617de8e1 |
406 | } |
407 | |
1d483eea |
408 | |
409 | int read_subbuffer(struct fd_pair *pair) |
410 | { |
4f31148b |
411 | unsigned int consumed_old; |
5ffb77aa |
412 | int err, ret=0; |
1d483eea |
413 | |
414 | |
c2ffa20f |
415 | err = ioctl(pair->channel, RELAY_GET_SUBBUF, |
4f31148b |
416 | &consumed_old); |
417 | printf("cookie : %u\n", consumed_old); |
469206ed |
418 | if(err != 0) { |
5ffb77aa |
419 | ret = errno; |
30478a4d |
420 | perror("Reserving sub buffer failed (everything is normal, it is due to concurrency)"); |
469206ed |
421 | goto get_error; |
1d483eea |
422 | } |
469206ed |
423 | |
424 | err = TEMP_FAILURE_RETRY(write(pair->trace, |
e4bed64a |
425 | pair->mmap |
426 | + (consumed_old & ((pair->n_subbufs * pair->subbuf_size)-1)), |
1d483eea |
427 | pair->subbuf_size)); |
469206ed |
428 | |
429 | if(err < 0) { |
5ffb77aa |
430 | ret = errno; |
1d483eea |
431 | perror("Error in writing to file"); |
469206ed |
432 | goto write_error; |
1d483eea |
433 | } |
a7eb8aa2 |
434 | #if 0 |
435 | err = fsync(pair->trace); |
436 | if(err < 0) { |
437 | ret = errno; |
438 | perror("Error in writing to file"); |
439 | goto write_error; |
440 | } |
441 | #endif //0 |
469206ed |
442 | write_error: |
c2ffa20f |
443 | err = ioctl(pair->channel, RELAY_PUT_SUBBUF, &consumed_old); |
469206ed |
444 | if(err != 0) { |
5ffb77aa |
445 | ret = errno; |
30478a4d |
446 | if(errno == EFAULT) { |
5ffb77aa |
447 | perror("Error in unreserving sub buffer\n"); |
30478a4d |
448 | } else if(errno == EIO) { |
4f31148b |
449 | perror("Reader has been pushed by the writer, last subbuffer corrupted."); |
ec8cce5a |
450 | /* FIXME : we may delete the last written buffer if we wish. */ |
4f31148b |
451 | } |
469206ed |
452 | goto get_error; |
1d483eea |
453 | } |
454 | |
469206ed |
455 | get_error: |
456 | return ret; |
1d483eea |
457 | } |
458 | |
459 | |
617de8e1 |
460 | |
357915bb |
461 | int map_channels(struct channel_trace_fd *fd_pairs, |
462 | int idx_begin, int idx_end) |
617de8e1 |
463 | { |
1d483eea |
464 | int i,j; |
e54e1d5d |
465 | int ret=0; |
1d483eea |
466 | |
469206ed |
467 | if(fd_pairs->num_pairs <= 0) { |
468 | printf("No channel to read\n"); |
469 | goto end; |
470 | } |
471 | |
1d483eea |
472 | /* Get the subbuf sizes and number */ |
473 | |
357915bb |
474 | for(i=idx_begin;i<idx_end;i++) { |
1d483eea |
475 | struct fd_pair *pair = &fd_pairs->pair[i]; |
90ccaa9a |
476 | |
c2ffa20f |
477 | ret = ioctl(pair->channel, RELAY_GET_N_SUBBUFS, |
1d483eea |
478 | &pair->n_subbufs); |
479 | if(ret != 0) { |
480 | perror("Error in getting the number of subbuffers"); |
481 | goto end; |
482 | } |
c2ffa20f |
483 | ret = ioctl(pair->channel, RELAY_GET_SUBBUF_SIZE, |
1d483eea |
484 | &pair->subbuf_size); |
485 | if(ret != 0) { |
486 | perror("Error in getting the size of the subbuffers"); |
487 | goto end; |
488 | } |
5ffb77aa |
489 | ret = pthread_mutex_init(&pair->mutex, NULL); /* Fast mutex */ |
490 | if(ret != 0) { |
491 | perror("Error in mutex init"); |
492 | goto end; |
493 | } |
1d483eea |
494 | } |
495 | |
496 | /* Mmap each FD */ |
357915bb |
497 | for(i=idx_begin;i<idx_end;i++) { |
1d483eea |
498 | struct fd_pair *pair = &fd_pairs->pair[i]; |
499 | |
500 | pair->mmap = mmap(0, pair->subbuf_size * pair->n_subbufs, PROT_READ, |
501 | MAP_SHARED, pair->channel, 0); |
502 | if(pair->mmap == MAP_FAILED) { |
503 | perror("Mmap error"); |
504 | goto munmap; |
505 | } |
506 | } |
507 | |
5ffb77aa |
508 | goto end; /* success */ |
1d483eea |
509 | |
e54e1d5d |
510 | /* Error handling */ |
511 | /* munmap only the successfully mmapped indexes */ |
512 | munmap: |
513 | /* Munmap each FD */ |
357915bb |
514 | for(j=idx_begin;j<i;j++) { |
e54e1d5d |
515 | struct fd_pair *pair = &fd_pairs->pair[j]; |
516 | int err_ret; |
517 | |
518 | err_ret = munmap(pair->mmap, pair->subbuf_size * pair->n_subbufs); |
519 | if(err_ret != 0) { |
520 | perror("Error in munmap"); |
521 | } |
522 | ret |= err_ret; |
523 | } |
524 | |
525 | end: |
526 | return ret; |
527 | |
528 | |
529 | } |
530 | |
531 | |
532 | int unmap_channels(struct channel_trace_fd *fd_pairs) |
533 | { |
534 | int j; |
535 | int ret=0; |
536 | |
537 | /* Munmap each FD */ |
538 | for(j=0;j<fd_pairs->num_pairs;j++) { |
539 | struct fd_pair *pair = &fd_pairs->pair[j]; |
540 | int err_ret; |
541 | |
542 | err_ret = munmap(pair->mmap, pair->subbuf_size * pair->n_subbufs); |
543 | if(err_ret != 0) { |
544 | perror("Error in munmap"); |
545 | } |
546 | ret |= err_ret; |
5ffb77aa |
547 | err_ret = pthread_mutex_destroy(&pair->mutex); |
548 | if(err_ret != 0) { |
549 | perror("Error in mutex destroy"); |
550 | } |
551 | ret |= err_ret; |
e54e1d5d |
552 | } |
553 | |
554 | return ret; |
555 | } |
556 | |
357915bb |
557 | #ifdef HAS_INOTIFY |
558 | /* Inotify event arrived. |
559 | * |
560 | * Only support add file for now. |
561 | */ |
562 | |
563 | int read_inotify(int inotify_fd, |
564 | struct channel_trace_fd *fd_pairs, |
565 | struct inotify_watch_array *iwatch_array) |
566 | { |
567 | char buf[sizeof(struct inotify_event) + PATH_MAX]; |
568 | char path_channel[PATH_MAX]; |
569 | char path_trace[PATH_MAX]; |
570 | ssize_t len; |
571 | struct inotify_event *ievent; |
572 | size_t offset; |
573 | unsigned int i; |
574 | int ret; |
575 | int old_num; |
576 | |
577 | offset = 0; |
578 | len = read(inotify_fd, buf, sizeof(struct inotify_event) + PATH_MAX); |
579 | if(len < 0) { |
580 | printf("Error in read from inotify FD %s.\n", strerror(len)); |
581 | return -1; |
582 | } |
583 | while(offset < len) { |
584 | ievent = (struct inotify_event *)&(buf[offset]); |
585 | for(i=0; i<iwatch_array->num; i++) { |
586 | if(iwatch_array->elem[i].wd == ievent->wd && |
587 | ievent->mask == IN_CREATE) { |
588 | printf("inotify wd %u event mask : %u for %s%s\n", |
589 | ievent->wd, ievent->mask, |
590 | iwatch_array->elem[i].path_channel, ievent->name); |
591 | old_num = fd_pairs->num_pairs; |
592 | strcpy(path_channel, iwatch_array->elem[i].path_channel); |
593 | strcat(path_channel, ievent->name); |
594 | strcpy(path_trace, iwatch_array->elem[i].path_trace); |
595 | strcat(path_trace, ievent->name); |
596 | if(ret = open_buffer_file(ievent->name, path_channel, |
597 | path_trace, fd_pairs)) { |
598 | printf("Error opening buffer file\n"); |
599 | return -1; |
600 | } |
601 | if(ret = map_channels(fd_pairs, old_num, fd_pairs->num_pairs)) { |
602 | printf("Error mapping channel\n"); |
603 | return -1; |
604 | } |
605 | |
606 | } |
607 | } |
608 | offset += sizeof(*ievent) + ievent->len; |
609 | } |
610 | } |
611 | #endif //HAS_INOTIFY |
e54e1d5d |
612 | |
613 | /* read_channels |
5ffb77aa |
614 | * |
615 | * Thread worker. |
e54e1d5d |
616 | * |
c2ffa20f |
617 | * Read the debugfs channels and write them in the paired tracefiles. |
e54e1d5d |
618 | * |
619 | * @fd_pairs : paired channels and trace files. |
620 | * |
357915bb |
621 | * returns 0 on success, -1 on error. |
e54e1d5d |
622 | * |
623 | * Note that the high priority polled channels are consumed first. We then poll |
624 | * again to see if these channels are still in priority. Only when no |
625 | * high priority channel is left, we start reading low priority channels. |
626 | * |
627 | * Note that a channel is considered high priority when the buffer is almost |
628 | * full. |
629 | */ |
630 | |
357915bb |
631 | int read_channels(unsigned int thread_num, struct channel_trace_fd *fd_pairs, |
632 | int inotify_fd, struct inotify_watch_array *iwatch_array) |
e54e1d5d |
633 | { |
357915bb |
634 | struct pollfd *pollfd = NULL; |
e54e1d5d |
635 | int i,j; |
636 | int num_rdy, num_hup; |
637 | int high_prio; |
5ffb77aa |
638 | int ret = 0; |
357915bb |
639 | int inotify_fds; |
640 | unsigned int old_num; |
e54e1d5d |
641 | |
357915bb |
642 | #ifdef HAS_INOTIFY |
643 | inotify_fds = 1; |
644 | #else |
645 | inotify_fds = 0; |
646 | #endif |
647 | |
648 | /* Start polling the FD. Keep one fd for inotify */ |
649 | pollfd = malloc((inotify_fds + fd_pairs->num_pairs) * sizeof(struct pollfd)); |
650 | |
651 | #ifdef HAS_INOTIFY |
652 | pollfd[0].fd = inotify_fd; |
653 | pollfd[0].events = POLLIN|POLLPRI; |
654 | #endif |
90ccaa9a |
655 | |
656 | for(i=0;i<fd_pairs->num_pairs;i++) { |
357915bb |
657 | pollfd[inotify_fds+i].fd = fd_pairs->pair[i].channel; |
658 | pollfd[inotify_fds+i].events = POLLIN|POLLPRI; |
90ccaa9a |
659 | } |
357915bb |
660 | |
90ccaa9a |
661 | while(1) { |
4f45ea55 |
662 | high_prio = 0; |
1d483eea |
663 | num_hup = 0; |
664 | #ifdef DEBUG |
665 | printf("Press a key for next poll...\n"); |
666 | char buf[1]; |
667 | read(STDIN_FILENO, &buf, 1); |
357915bb |
668 | printf("Next poll (polling %d fd) :\n", 1+fd_pairs->num_pairs); |
1d483eea |
669 | #endif //DEBUG |
357915bb |
670 | |
1d483eea |
671 | /* Have we received a signal ? */ |
672 | if(quit_program) break; |
673 | |
357915bb |
674 | num_rdy = poll(pollfd, inotify_fds+fd_pairs->num_pairs, -1); |
90ccaa9a |
675 | if(num_rdy == -1) { |
676 | perror("Poll error"); |
1d483eea |
677 | goto free_fd; |
90ccaa9a |
678 | } |
679 | |
680 | printf("Data received\n"); |
357915bb |
681 | #ifdef HAS_INOTIFY |
682 | switch(pollfd[0].revents) { |
683 | case POLLERR: |
684 | printf("Error returned in polling inotify fd %d.\n", pollfd[0].fd); |
685 | break; |
686 | case POLLHUP: |
687 | printf("Polling inotify fd %d tells it has hung up.\n", pollfd[0].fd); |
688 | break; |
689 | case POLLNVAL: |
690 | printf("Polling inotify fd %d tells fd is not open.\n", pollfd[0].fd); |
691 | break; |
692 | case POLLPRI: |
693 | case POLLIN: |
694 | printf("Polling inotify fd %d : data ready.\n", pollfd[0].fd); |
695 | old_num = fd_pairs->num_pairs; |
696 | read_inotify(inotify_fd, fd_pairs, iwatch_array); |
697 | pollfd = realloc(pollfd, |
698 | (inotify_fds + fd_pairs->num_pairs) * sizeof(struct pollfd)); |
699 | for(i=old_num;i<fd_pairs->num_pairs;i++) { |
700 | pollfd[inotify_fds+i].fd = fd_pairs->pair[i].channel; |
701 | pollfd[inotify_fds+i].events = POLLIN|POLLPRI; |
702 | } |
703 | break; |
704 | } |
705 | #endif |
90ccaa9a |
706 | |
357915bb |
707 | for(i=inotify_fds;i<inotify_fds+fd_pairs->num_pairs;i++) { |
90ccaa9a |
708 | switch(pollfd[i].revents) { |
709 | case POLLERR: |
710 | printf("Error returned in polling fd %d.\n", pollfd[i].fd); |
1d483eea |
711 | num_hup++; |
90ccaa9a |
712 | break; |
713 | case POLLHUP: |
714 | printf("Polling fd %d tells it has hung up.\n", pollfd[i].fd); |
1d483eea |
715 | num_hup++; |
90ccaa9a |
716 | break; |
717 | case POLLNVAL: |
718 | printf("Polling fd %d tells fd is not open.\n", pollfd[i].fd); |
1d483eea |
719 | num_hup++; |
90ccaa9a |
720 | break; |
721 | case POLLPRI: |
357915bb |
722 | if(pthread_mutex_trylock(&fd_pairs->pair[i-inotify_fds].mutex) == 0) { |
5ffb77aa |
723 | printf("Urgent read on fd %d\n", pollfd[i].fd); |
724 | /* Take care of high priority channels first. */ |
725 | high_prio = 1; |
726 | /* it's ok to have an unavailable subbuffer */ |
357915bb |
727 | ret = read_subbuffer(&fd_pairs->pair[i-inotify_fds]); |
30478a4d |
728 | if(ret == EAGAIN) ret = 0; |
cdad9787 |
729 | |
357915bb |
730 | ret = pthread_mutex_unlock(&fd_pairs->pair[i-inotify_fds].mutex); |
5ffb77aa |
731 | if(ret) |
732 | printf("Error in mutex unlock : %s\n", strerror(ret)); |
733 | } |
90ccaa9a |
734 | break; |
4f45ea55 |
735 | } |
90ccaa9a |
736 | } |
357915bb |
737 | /* If every buffer FD has hung up, we end the read loop here */ |
1d483eea |
738 | if(num_hup == fd_pairs->num_pairs) break; |
90ccaa9a |
739 | |
4f45ea55 |
740 | if(!high_prio) { |
357915bb |
741 | for(i=inotify_fds;i<inotify_fds+fd_pairs->num_pairs;i++) { |
4f45ea55 |
742 | switch(pollfd[i].revents) { |
743 | case POLLIN: |
357915bb |
744 | if(pthread_mutex_trylock(&fd_pairs->pair[i-inotify_fds].mutex) == 0) { |
5ffb77aa |
745 | /* Take care of low priority channels. */ |
746 | printf("Normal read on fd %d\n", pollfd[i].fd); |
747 | /* it's ok to have an unavailable subbuffer */ |
357915bb |
748 | ret = read_subbuffer(&fd_pairs->pair[i-inotify_fds]); |
30478a4d |
749 | if(ret == EAGAIN) ret = 0; |
cdad9787 |
750 | |
357915bb |
751 | ret = pthread_mutex_unlock(&fd_pairs->pair[i-inotify_fds].mutex); |
5ffb77aa |
752 | if(ret) |
753 | printf("Error in mutex unlock : %s\n", strerror(ret)); |
754 | } |
4f45ea55 |
755 | break; |
756 | } |
757 | } |
90ccaa9a |
758 | } |
759 | |
760 | } |
761 | |
1d483eea |
762 | free_fd: |
90ccaa9a |
763 | free(pollfd); |
764 | |
1d483eea |
765 | end: |
357915bb |
766 | return ret; |
617de8e1 |
767 | } |
768 | |
769 | |
357915bb |
770 | void close_channel_trace_pairs(struct channel_trace_fd *fd_pairs, int inotify_fd, |
771 | struct inotify_watch_array *iwatch_array) |
617de8e1 |
772 | { |
90ccaa9a |
773 | int i; |
774 | int ret; |
617de8e1 |
775 | |
90ccaa9a |
776 | for(i=0;i<fd_pairs->num_pairs;i++) { |
777 | ret = close(fd_pairs->pair[i].channel); |
778 | if(ret == -1) perror("Close error on channel"); |
779 | ret = close(fd_pairs->pair[i].trace); |
780 | if(ret == -1) perror("Close error on trace"); |
781 | } |
782 | free(fd_pairs->pair); |
357915bb |
783 | free(iwatch_array->elem); |
784 | } |
785 | |
786 | /* Thread worker */ |
787 | void * thread_main(void *arg) |
788 | { |
789 | struct channel_trace_fd fd_pairs = { NULL, 0 }; |
790 | int inotify_fd = -1; |
791 | struct inotify_watch_array inotify_watch_array = { NULL, 0 }; |
792 | int ret = 0; |
793 | unsigned int thread_num = (unsigned int)arg; |
794 | |
795 | inotify_fd = inotify_init(); |
796 | |
797 | if(ret = open_channel_trace_pairs(channel_name, trace_name, &fd_pairs, |
798 | &inotify_fd, &inotify_watch_array)) |
799 | goto close_channel; |
800 | |
801 | if(ret = map_channels(&fd_pairs, 0, fd_pairs.num_pairs)) |
802 | goto close_channel; |
803 | |
804 | ret = read_channels(thread_num, &fd_pairs, inotify_fd, &inotify_watch_array); |
805 | |
806 | ret |= unmap_channels(&fd_pairs); |
807 | |
808 | close_channel: |
809 | close_channel_trace_pairs(&fd_pairs, inotify_fd, &inotify_watch_array); |
810 | if(inotify_fd >= 0) |
811 | close(inotify_fd); |
812 | |
813 | return (void*)ret; |
617de8e1 |
814 | } |
815 | |
816 | int main(int argc, char ** argv) |
817 | { |
e54e1d5d |
818 | int ret = 0; |
1d483eea |
819 | struct sigaction act; |
5ffb77aa |
820 | pthread_t *tids; |
821 | unsigned int i; |
822 | void *tret; |
617de8e1 |
823 | |
824 | ret = parse_arguments(argc, argv); |
825 | |
826 | if(ret != 0) show_arguments(); |
827 | if(ret < 0) return EINVAL; |
828 | if(ret > 0) return 0; |
829 | |
830 | show_info(); |
831 | |
832 | if(daemon_mode) { |
2253bb8e |
833 | ret = daemon(0, 0); |
002f91bb |
834 | |
835 | if(ret == -1) { |
836 | perror("An error occured while daemonizing."); |
837 | exit(-1); |
838 | } |
839 | } |
617de8e1 |
840 | |
1d483eea |
841 | /* Connect the signal handlers */ |
842 | act.sa_handler = handler; |
843 | act.sa_flags = 0; |
844 | sigemptyset(&(act.sa_mask)); |
845 | sigaddset(&(act.sa_mask), SIGTERM); |
846 | sigaddset(&(act.sa_mask), SIGQUIT); |
847 | sigaddset(&(act.sa_mask), SIGINT); |
848 | sigaction(SIGTERM, &act, NULL); |
849 | sigaction(SIGQUIT, &act, NULL); |
850 | sigaction(SIGINT, &act, NULL); |
851 | |
5ffb77aa |
852 | tids = malloc(sizeof(pthread_t) * num_threads); |
853 | for(i=0; i<num_threads; i++) { |
ae410d24 |
854 | |
357915bb |
855 | ret = pthread_create(&tids[i], NULL, thread_main, (void*)i); |
5ffb77aa |
856 | if(ret) { |
857 | perror("Error creating thread"); |
858 | break; |
859 | } |
860 | } |
617de8e1 |
861 | |
5ffb77aa |
862 | for(i=0; i<num_threads; i++) { |
863 | ret = pthread_join(tids[i], &tret); |
864 | if(ret) { |
865 | perror("Error joining thread"); |
866 | break; |
867 | } |
868 | if((int)tret != 0) { |
a7eb8aa2 |
869 | printf("Error %s occured in thread %u\n", strerror((int)tret), i); |
5ffb77aa |
870 | } |
871 | } |
872 | |
873 | free(tids); |
874 | |
617de8e1 |
875 | return ret; |
876 | } |