6cecb9cf |
1 | /* lttd |
2 | * |
3 | * Linux Trace Toolkit Daemon |
4 | * |
bb01fdc6 |
5 | * This is a simple daemon that reads a few relay+debugfs channels and save |
6 | * them in a trace. |
6cecb9cf |
7 | * |
d66cc831 |
8 | * CPU hot-plugging is supported using inotify. |
6cecb9cf |
9 | * |
10 | * Copyright 2005 - |
11 | * Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> |
12 | */ |
13 | |
4e4d11b3 |
14 | #ifdef HAVE_CONFIG_H |
13474e75 |
15 | #include <config.h> |
4e4d11b3 |
16 | #endif |
17 | |
c3e8c24f |
18 | #define _REENTRANT |
4e4d11b3 |
19 | #define _GNU_SOURCE |
c3e8c24f |
20 | #include <features.h> |
6cecb9cf |
21 | #include <stdio.h> |
af4061b2 |
22 | #include <unistd.h> |
6cecb9cf |
23 | #include <errno.h> |
24 | #include <sys/types.h> |
25 | #include <sys/stat.h> |
6cecb9cf |
26 | #include <stdlib.h> |
27 | #include <dirent.h> |
28 | #include <string.h> |
9e7dbe44 |
29 | #include <fcntl.h> |
30 | #include <sys/poll.h> |
af4061b2 |
31 | #include <sys/mman.h> |
32 | #include <signal.h> |
c3e8c24f |
33 | #include <pthread.h> |
47dbc661 |
34 | #include <sys/syscall.h> |
35 | #include <unistd.h> |
36 | #include <asm/ioctls.h> |
37 | |
38 | #include <linux/version.h> |
af4061b2 |
39 | |
40 | /* Relayfs IOCTL */ |
41 | #include <asm/ioctl.h> |
42 | #include <asm/types.h> |
43 | |
44 | /* Get the next sub buffer that can be read. */ |
f2bd6bd2 |
45 | #define RELAY_GET_SUBBUF _IOR(0xF5, 0x00,__u32) |
af4061b2 |
46 | /* Release the oldest reserved (by "get") sub buffer. */ |
f2bd6bd2 |
47 | #define RELAY_PUT_SUBBUF _IOW(0xF5, 0x01,__u32) |
af4061b2 |
48 | /* returns the number of sub buffers in the per cpu channel. */ |
f2bd6bd2 |
49 | #define RELAY_GET_N_SUBBUFS _IOR(0xF5, 0x02,__u32) |
af4061b2 |
50 | /* returns the size of the sub buffers. */ |
f2bd6bd2 |
51 | #define RELAY_GET_SUBBUF_SIZE _IOR(0xF5, 0x03,__u32) |
af4061b2 |
52 | |
47dbc661 |
53 | #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,14) |
54 | #include <linux/inotify.h> |
55 | /* From the inotify-tools 2.6 package */ |
56 | static inline int inotify_init (void) |
57 | { |
58 | return syscall (__NR_inotify_init); |
59 | } |
60 | |
61 | static inline int inotify_add_watch (int fd, const char *name, __u32 mask) |
62 | { |
63 | return syscall (__NR_inotify_add_watch, fd, name, mask); |
64 | } |
65 | |
66 | static inline int inotify_rm_watch (int fd, __u32 wd) |
67 | { |
68 | return syscall (__NR_inotify_rm_watch, fd, wd); |
69 | } |
70 | #define HAS_INOTIFY |
71 | #else |
72 | static inline int inotify_init (void) |
73 | { |
74 | return -1; |
75 | } |
af4061b2 |
76 | |
47dbc661 |
77 | static inline int inotify_add_watch (int fd, const char *name, __u32 mask) |
78 | { |
79 | return 0; |
80 | } |
81 | |
82 | static inline int inotify_rm_watch (int fd, __u32 wd) |
83 | { |
84 | return 0; |
85 | } |
86 | #undef HAS_INOTIFY |
87 | #endif |
6cecb9cf |
88 | |
89 | enum { |
90 | GET_SUBBUF, |
91 | PUT_SUBBUF, |
92 | GET_N_BUBBUFS, |
93 | GET_SUBBUF_SIZE |
94 | }; |
95 | |
96 | struct fd_pair { |
97 | int channel; |
98 | int trace; |
af4061b2 |
99 | unsigned int n_subbufs; |
100 | unsigned int subbuf_size; |
101 | void *mmap; |
22acb617 |
102 | pthread_mutex_t mutex; |
6cecb9cf |
103 | }; |
104 | |
105 | struct channel_trace_fd { |
106 | struct fd_pair *pair; |
107 | int num_pairs; |
108 | }; |
109 | |
47dbc661 |
110 | struct inotify_watch { |
111 | int wd; |
112 | char path_channel[PATH_MAX]; |
113 | char path_trace[PATH_MAX]; |
114 | }; |
115 | |
116 | struct inotify_watch_array { |
117 | struct inotify_watch *elem; |
118 | int num; |
119 | }; |
120 | |
d61d094a |
121 | static __thread int thread_pipe[2]; |
d66cc831 |
122 | |
123 | struct channel_trace_fd fd_pairs = { NULL, 0 }; |
124 | int inotify_fd = -1; |
125 | struct inotify_watch_array inotify_watch_array = { NULL, 0 }; |
126 | |
127 | /* protects fd_pairs and inotify_watch_array */ |
128 | pthread_rwlock_t fd_pairs_lock = PTHREAD_RWLOCK_INITIALIZER; |
129 | |
130 | |
d24c12e7 |
131 | static char *trace_name = NULL; |
132 | static char *channel_name = NULL; |
133 | static int daemon_mode = 0; |
134 | static int append_mode = 0; |
135 | static unsigned long num_threads = 1; |
af4061b2 |
136 | volatile static int quit_program = 0; /* For signal handler */ |
d24c12e7 |
137 | static int dump_flight_only = 0; |
138 | static int dump_normal_only = 0; |
51f9cfd2 |
139 | static int verbose_mode = 0; |
140 | |
141 | #define printf_verbose(fmt, args...) \ |
142 | do { \ |
143 | if (verbose_mode) \ |
144 | printf(fmt, ##args); \ |
145 | } while (0) |
6cecb9cf |
146 | |
147 | /* Args : |
148 | * |
149 | * -t directory Directory name of the trace to write to. Will be created. |
bb01fdc6 |
150 | * -c directory Root directory of the debugfs trace channels. |
6cecb9cf |
151 | * -d Run in background (daemon). |
51f9cfd2 |
152 | * -a Trace append mode. |
153 | * -s Send SIGUSR1 to parent when ready for IO. |
6cecb9cf |
154 | */ |
155 | void show_arguments(void) |
156 | { |
157 | printf("Please use the following arguments :\n"); |
158 | printf("\n"); |
159 | printf("-t directory Directory name of the trace to write to.\n" |
160 | " It will be created.\n"); |
bb01fdc6 |
161 | printf("-c directory Root directory of the debugfs trace channels.\n"); |
6cecb9cf |
162 | printf("-d Run in background (daemon).\n"); |
9e7dbe44 |
163 | printf("-a Append to an possibly existing trace.\n"); |
22acb617 |
164 | printf("-N Number of threads to start.\n"); |
d24c12e7 |
165 | printf("-f Dump only flight recorder channels.\n"); |
166 | printf("-n Dump only normal channels.\n"); |
51f9cfd2 |
167 | printf("-v Verbose mode.\n"); |
6cecb9cf |
168 | printf("\n"); |
169 | } |
170 | |
171 | |
172 | /* parse_arguments |
173 | * |
174 | * Parses the command line arguments. |
175 | * |
176 | * Returns 1 if the arguments were correct, but doesn't ask for program |
177 | * continuation. Returns -1 if the arguments are incorrect, or 0 if OK. |
178 | */ |
179 | int parse_arguments(int argc, char **argv) |
180 | { |
181 | int ret = 0; |
182 | int argn = 1; |
183 | |
184 | if(argc == 2) { |
185 | if(strcmp(argv[1], "-h") == 0) { |
186 | return 1; |
187 | } |
188 | } |
189 | |
9e7dbe44 |
190 | while(argn < argc) { |
6cecb9cf |
191 | |
192 | switch(argv[argn][0]) { |
193 | case '-': |
194 | switch(argv[argn][1]) { |
195 | case 't': |
9e7dbe44 |
196 | if(argn+1 < argc) { |
197 | trace_name = argv[argn+1]; |
198 | argn++; |
199 | } |
6cecb9cf |
200 | break; |
201 | case 'c': |
9e7dbe44 |
202 | if(argn+1 < argc) { |
203 | channel_name = argv[argn+1]; |
204 | argn++; |
205 | } |
6cecb9cf |
206 | break; |
207 | case 'd': |
208 | daemon_mode = 1; |
209 | break; |
9e7dbe44 |
210 | case 'a': |
211 | append_mode = 1; |
212 | break; |
22acb617 |
213 | case 'N': |
c3e8c24f |
214 | if(argn+1 < argc) { |
215 | num_threads = strtoul(argv[argn+1], NULL, 0); |
216 | argn++; |
217 | } |
218 | break; |
d24c12e7 |
219 | case 'f': |
220 | dump_flight_only = 1; |
221 | break; |
222 | case 'n': |
223 | dump_normal_only = 1; |
224 | break; |
51f9cfd2 |
225 | case 'v': |
226 | verbose_mode = 1; |
227 | break; |
6cecb9cf |
228 | default: |
229 | printf("Invalid argument '%s'.\n", argv[argn]); |
230 | printf("\n"); |
231 | ret = -1; |
232 | } |
233 | break; |
234 | default: |
235 | printf("Invalid argument '%s'.\n", argv[argn]); |
236 | printf("\n"); |
237 | ret = -1; |
238 | } |
239 | argn++; |
240 | } |
241 | |
242 | if(trace_name == NULL) { |
243 | printf("Please specify a trace name.\n"); |
244 | printf("\n"); |
245 | ret = -1; |
246 | } |
247 | |
248 | if(channel_name == NULL) { |
249 | printf("Please specify a channel name.\n"); |
250 | printf("\n"); |
251 | ret = -1; |
252 | } |
253 | |
254 | return ret; |
255 | } |
256 | |
257 | void show_info(void) |
258 | { |
e7480f75 |
259 | printf("Linux Trace Toolkit Trace Daemon " VERSION "\n"); |
6cecb9cf |
260 | printf("\n"); |
bb01fdc6 |
261 | printf("Reading from debugfs directory : %s\n", channel_name); |
6cecb9cf |
262 | printf("Writing to trace directory : %s\n", trace_name); |
263 | printf("\n"); |
264 | } |
265 | |
266 | |
af4061b2 |
267 | /* signal handling */ |
268 | |
269 | static void handler(int signo) |
270 | { |
271 | printf("Signal %d received : exiting cleanly\n", signo); |
272 | quit_program = 1; |
273 | } |
274 | |
275 | |
47dbc661 |
276 | int open_buffer_file(char *filename, char *path_channel, char *path_trace, |
277 | struct channel_trace_fd *fd_pairs) |
278 | { |
279 | int open_ret = 0; |
280 | int ret = 0; |
281 | struct stat stat_buf; |
282 | |
283 | if(strncmp(filename, "flight-", sizeof("flight-")-1) != 0) { |
284 | if(dump_flight_only) { |
51f9cfd2 |
285 | printf_verbose("Skipping normal channel %s\n", |
286 | path_channel); |
47dbc661 |
287 | return 0; |
288 | } |
289 | } else { |
290 | if(dump_normal_only) { |
51f9cfd2 |
291 | printf_verbose("Skipping flight channel %s\n", |
292 | path_channel); |
47dbc661 |
293 | return 0; |
294 | } |
295 | } |
51f9cfd2 |
296 | printf_verbose("Opening file.\n"); |
47dbc661 |
297 | |
298 | fd_pairs->pair = realloc(fd_pairs->pair, |
299 | ++fd_pairs->num_pairs * sizeof(struct fd_pair)); |
300 | |
301 | /* Open the channel in read mode */ |
302 | fd_pairs->pair[fd_pairs->num_pairs-1].channel = |
303 | open(path_channel, O_RDONLY | O_NONBLOCK); |
304 | if(fd_pairs->pair[fd_pairs->num_pairs-1].channel == -1) { |
305 | perror(path_channel); |
306 | fd_pairs->num_pairs--; |
307 | return 0; /* continue */ |
308 | } |
309 | /* Open the trace in write mode, only append if append_mode */ |
310 | ret = stat(path_trace, &stat_buf); |
311 | if(ret == 0) { |
312 | if(append_mode) { |
51f9cfd2 |
313 | printf_verbose("Appending to file %s as requested\n", |
314 | path_trace); |
47dbc661 |
315 | |
316 | fd_pairs->pair[fd_pairs->num_pairs-1].trace = |
317 | open(path_trace, O_WRONLY|O_APPEND, |
318 | S_IRWXU|S_IRWXG|S_IRWXO); |
319 | |
320 | if(fd_pairs->pair[fd_pairs->num_pairs-1].trace == -1) { |
321 | perror(path_trace); |
322 | } |
323 | } else { |
324 | printf("File %s exists, cannot open. Try append mode.\n", path_trace); |
325 | open_ret = -1; |
326 | goto end; |
327 | } |
328 | } else { |
329 | if(errno == ENOENT) { |
330 | fd_pairs->pair[fd_pairs->num_pairs-1].trace = |
331 | open(path_trace, O_WRONLY|O_CREAT|O_EXCL, |
332 | S_IRWXU|S_IRWXG|S_IRWXO); |
333 | if(fd_pairs->pair[fd_pairs->num_pairs-1].trace == -1) { |
334 | perror(path_trace); |
335 | } |
336 | } |
337 | } |
338 | end: |
339 | return open_ret; |
340 | } |
af4061b2 |
341 | |
6cecb9cf |
342 | int open_channel_trace_pairs(char *subchannel_name, char *subtrace_name, |
47dbc661 |
343 | struct channel_trace_fd *fd_pairs, int *inotify_fd, |
344 | struct inotify_watch_array *iwatch_array) |
6cecb9cf |
345 | { |
346 | DIR *channel_dir = opendir(subchannel_name); |
347 | struct dirent *entry; |
348 | struct stat stat_buf; |
349 | int ret; |
350 | char path_channel[PATH_MAX]; |
351 | int path_channel_len; |
352 | char *path_channel_ptr; |
353 | char path_trace[PATH_MAX]; |
354 | int path_trace_len; |
355 | char *path_trace_ptr; |
4d508021 |
356 | int open_ret = 0; |
6cecb9cf |
357 | |
358 | if(channel_dir == NULL) { |
359 | perror(subchannel_name); |
02ba971e |
360 | open_ret = ENOENT; |
4d508021 |
361 | goto end; |
6cecb9cf |
362 | } |
363 | |
51f9cfd2 |
364 | printf_verbose("Creating trace subdirectory %s\n", subtrace_name); |
6cecb9cf |
365 | ret = mkdir(subtrace_name, S_IRWXU|S_IRWXG|S_IRWXO); |
366 | if(ret == -1) { |
3986d00b |
367 | if(errno != EEXIST) { |
9e7dbe44 |
368 | perror(subtrace_name); |
4d508021 |
369 | open_ret = -1; |
02ba971e |
370 | goto end; |
9e7dbe44 |
371 | } |
6cecb9cf |
372 | } |
373 | |
374 | strncpy(path_channel, subchannel_name, PATH_MAX-1); |
375 | path_channel_len = strlen(path_channel); |
376 | path_channel[path_channel_len] = '/'; |
377 | path_channel_len++; |
378 | path_channel_ptr = path_channel + path_channel_len; |
379 | |
380 | strncpy(path_trace, subtrace_name, PATH_MAX-1); |
381 | path_trace_len = strlen(path_trace); |
382 | path_trace[path_trace_len] = '/'; |
383 | path_trace_len++; |
384 | path_trace_ptr = path_trace + path_trace_len; |
385 | |
47dbc661 |
386 | #ifdef HAS_INOTIFY |
387 | iwatch_array->elem = realloc(iwatch_array->elem, |
388 | ++iwatch_array->num * sizeof(struct inotify_watch)); |
389 | |
51f9cfd2 |
390 | printf_verbose("Adding inotify for channel %s\n", path_channel); |
47dbc661 |
391 | iwatch_array->elem[iwatch_array->num-1].wd = inotify_add_watch(*inotify_fd, path_channel, IN_CREATE); |
392 | strcpy(iwatch_array->elem[iwatch_array->num-1].path_channel, path_channel); |
393 | strcpy(iwatch_array->elem[iwatch_array->num-1].path_trace, path_trace); |
51f9cfd2 |
394 | printf_verbose("Added inotify for channel %s, wd %u\n", |
395 | iwatch_array->elem[iwatch_array->num-1].path_channel, |
47dbc661 |
396 | iwatch_array->elem[iwatch_array->num-1].wd); |
397 | #endif |
398 | |
6cecb9cf |
399 | while((entry = readdir(channel_dir)) != NULL) { |
400 | |
401 | if(entry->d_name[0] == '.') continue; |
402 | |
403 | strncpy(path_channel_ptr, entry->d_name, PATH_MAX - path_channel_len); |
404 | strncpy(path_trace_ptr, entry->d_name, PATH_MAX - path_trace_len); |
405 | |
406 | ret = stat(path_channel, &stat_buf); |
407 | if(ret == -1) { |
408 | perror(path_channel); |
409 | continue; |
410 | } |
411 | |
51f9cfd2 |
412 | printf_verbose("Channel file : %s\n", path_channel); |
6cecb9cf |
413 | |
414 | if(S_ISDIR(stat_buf.st_mode)) { |
415 | |
51f9cfd2 |
416 | printf_verbose("Entering channel subdirectory...\n"); |
47dbc661 |
417 | ret = open_channel_trace_pairs(path_channel, path_trace, fd_pairs, |
418 | inotify_fd, iwatch_array); |
6cecb9cf |
419 | if(ret < 0) continue; |
9e7dbe44 |
420 | } else if(S_ISREG(stat_buf.st_mode)) { |
47dbc661 |
421 | open_ret = open_buffer_file(entry->d_name, path_channel, path_trace, |
422 | fd_pairs); |
423 | if(open_ret) |
424 | goto end; |
6cecb9cf |
425 | } |
6cecb9cf |
426 | } |
427 | |
02ba971e |
428 | end: |
6cecb9cf |
429 | closedir(channel_dir); |
430 | |
02ba971e |
431 | return open_ret; |
6cecb9cf |
432 | } |
433 | |
af4061b2 |
434 | |
435 | int read_subbuffer(struct fd_pair *pair) |
436 | { |
d61d094a |
437 | unsigned int consumed_old; |
438 | int err; |
439 | long ret; |
440 | unsigned long len, offset; |
af4061b2 |
441 | |
442 | |
d61d094a |
443 | err = ioctl(pair->channel, RELAY_GET_SUBBUF, &consumed_old); |
51f9cfd2 |
444 | printf_verbose("cookie : %u\n", consumed_old); |
13474e75 |
445 | if(err != 0) { |
22acb617 |
446 | ret = errno; |
63bf9ed1 |
447 | perror("Reserving sub buffer failed (everything is normal, it is due to concurrency)"); |
13474e75 |
448 | goto get_error; |
af4061b2 |
449 | } |
d61d094a |
450 | #if 0 |
13474e75 |
451 | err = TEMP_FAILURE_RETRY(write(pair->trace, |
2312de30 |
452 | pair->mmap |
453 | + (consumed_old & ((pair->n_subbufs * pair->subbuf_size)-1)), |
af4061b2 |
454 | pair->subbuf_size)); |
13474e75 |
455 | |
456 | if(err < 0) { |
22acb617 |
457 | ret = errno; |
af4061b2 |
458 | perror("Error in writing to file"); |
13474e75 |
459 | goto write_error; |
af4061b2 |
460 | } |
d61d094a |
461 | #endif //0 |
462 | len = pair->subbuf_size; |
463 | offset = 0; |
464 | while (len > 0) { |
51f9cfd2 |
465 | printf_verbose("splice chan to pipe offset %lu\n", offset); |
d61d094a |
466 | ret = splice(pair->channel, &offset, thread_pipe[1], NULL, |
467 | len, SPLICE_F_MOVE); |
51f9cfd2 |
468 | printf_verbose("splice chan to pipe ret %ld\n", ret); |
d61d094a |
469 | if (ret < 0) { |
470 | perror("Error in relay splice"); |
471 | goto write_error; |
472 | } |
473 | ret = splice(thread_pipe[0], NULL, pair->trace, NULL, |
474 | ret, SPLICE_F_MOVE); |
51f9cfd2 |
475 | printf_verbose("splice pipe to file %ld\n", ret); |
d61d094a |
476 | if (ret < 0) { |
477 | perror("Error in file splice"); |
478 | goto write_error; |
479 | } |
480 | len -= ret; |
481 | } |
482 | |
c5fdfca5 |
483 | #if 0 |
484 | err = fsync(pair->trace); |
485 | if(err < 0) { |
486 | ret = errno; |
487 | perror("Error in writing to file"); |
488 | goto write_error; |
489 | } |
490 | #endif //0 |
13474e75 |
491 | write_error: |
d61d094a |
492 | ret = 0; |
bb01fdc6 |
493 | err = ioctl(pair->channel, RELAY_PUT_SUBBUF, &consumed_old); |
13474e75 |
494 | if(err != 0) { |
22acb617 |
495 | ret = errno; |
63bf9ed1 |
496 | if(errno == EFAULT) { |
22acb617 |
497 | perror("Error in unreserving sub buffer\n"); |
63bf9ed1 |
498 | } else if(errno == EIO) { |
12bcec97 |
499 | perror("Reader has been pushed by the writer, last subbuffer corrupted."); |
db9d75c0 |
500 | /* FIXME : we may delete the last written buffer if we wish. */ |
12bcec97 |
501 | } |
13474e75 |
502 | goto get_error; |
af4061b2 |
503 | } |
504 | |
13474e75 |
505 | get_error: |
506 | return ret; |
af4061b2 |
507 | } |
508 | |
509 | |
47dbc661 |
510 | int map_channels(struct channel_trace_fd *fd_pairs, |
511 | int idx_begin, int idx_end) |
6cecb9cf |
512 | { |
af4061b2 |
513 | int i,j; |
c3e8c24f |
514 | int ret=0; |
af4061b2 |
515 | |
13474e75 |
516 | if(fd_pairs->num_pairs <= 0) { |
517 | printf("No channel to read\n"); |
518 | goto end; |
519 | } |
520 | |
af4061b2 |
521 | /* Get the subbuf sizes and number */ |
522 | |
47dbc661 |
523 | for(i=idx_begin;i<idx_end;i++) { |
af4061b2 |
524 | struct fd_pair *pair = &fd_pairs->pair[i]; |
9e7dbe44 |
525 | |
bb01fdc6 |
526 | ret = ioctl(pair->channel, RELAY_GET_N_SUBBUFS, |
af4061b2 |
527 | &pair->n_subbufs); |
528 | if(ret != 0) { |
529 | perror("Error in getting the number of subbuffers"); |
530 | goto end; |
531 | } |
bb01fdc6 |
532 | ret = ioctl(pair->channel, RELAY_GET_SUBBUF_SIZE, |
af4061b2 |
533 | &pair->subbuf_size); |
534 | if(ret != 0) { |
535 | perror("Error in getting the size of the subbuffers"); |
536 | goto end; |
537 | } |
22acb617 |
538 | ret = pthread_mutex_init(&pair->mutex, NULL); /* Fast mutex */ |
539 | if(ret != 0) { |
540 | perror("Error in mutex init"); |
541 | goto end; |
542 | } |
af4061b2 |
543 | } |
544 | |
d61d094a |
545 | #if 0 |
af4061b2 |
546 | /* Mmap each FD */ |
47dbc661 |
547 | for(i=idx_begin;i<idx_end;i++) { |
af4061b2 |
548 | struct fd_pair *pair = &fd_pairs->pair[i]; |
549 | |
550 | pair->mmap = mmap(0, pair->subbuf_size * pair->n_subbufs, PROT_READ, |
551 | MAP_SHARED, pair->channel, 0); |
552 | if(pair->mmap == MAP_FAILED) { |
553 | perror("Mmap error"); |
554 | goto munmap; |
555 | } |
556 | } |
557 | |
22acb617 |
558 | goto end; /* success */ |
af4061b2 |
559 | |
c3e8c24f |
560 | /* Error handling */ |
561 | /* munmap only the successfully mmapped indexes */ |
562 | munmap: |
563 | /* Munmap each FD */ |
47dbc661 |
564 | for(j=idx_begin;j<i;j++) { |
c3e8c24f |
565 | struct fd_pair *pair = &fd_pairs->pair[j]; |
566 | int err_ret; |
567 | |
568 | err_ret = munmap(pair->mmap, pair->subbuf_size * pair->n_subbufs); |
569 | if(err_ret != 0) { |
570 | perror("Error in munmap"); |
571 | } |
572 | ret |= err_ret; |
573 | } |
574 | |
d61d094a |
575 | #endif //0 |
c3e8c24f |
576 | end: |
577 | return ret; |
c3e8c24f |
578 | } |
579 | |
c3e8c24f |
580 | int unmap_channels(struct channel_trace_fd *fd_pairs) |
581 | { |
582 | int j; |
583 | int ret=0; |
584 | |
585 | /* Munmap each FD */ |
586 | for(j=0;j<fd_pairs->num_pairs;j++) { |
587 | struct fd_pair *pair = &fd_pairs->pair[j]; |
588 | int err_ret; |
589 | |
d61d094a |
590 | #if 0 |
c3e8c24f |
591 | err_ret = munmap(pair->mmap, pair->subbuf_size * pair->n_subbufs); |
592 | if(err_ret != 0) { |
593 | perror("Error in munmap"); |
594 | } |
595 | ret |= err_ret; |
d61d094a |
596 | #endif //0 |
22acb617 |
597 | err_ret = pthread_mutex_destroy(&pair->mutex); |
598 | if(err_ret != 0) { |
599 | perror("Error in mutex destroy"); |
600 | } |
601 | ret |= err_ret; |
c3e8c24f |
602 | } |
603 | |
604 | return ret; |
605 | } |
606 | |
47dbc661 |
607 | #ifdef HAS_INOTIFY |
608 | /* Inotify event arrived. |
609 | * |
610 | * Only support add file for now. |
611 | */ |
612 | |
613 | int read_inotify(int inotify_fd, |
614 | struct channel_trace_fd *fd_pairs, |
615 | struct inotify_watch_array *iwatch_array) |
616 | { |
617 | char buf[sizeof(struct inotify_event) + PATH_MAX]; |
618 | char path_channel[PATH_MAX]; |
619 | char path_trace[PATH_MAX]; |
620 | ssize_t len; |
621 | struct inotify_event *ievent; |
622 | size_t offset; |
623 | unsigned int i; |
624 | int ret; |
625 | int old_num; |
626 | |
627 | offset = 0; |
628 | len = read(inotify_fd, buf, sizeof(struct inotify_event) + PATH_MAX); |
629 | if(len < 0) { |
d66cc831 |
630 | |
631 | if(errno == EAGAIN) |
632 | return 0; /* another thread got the data before us */ |
633 | |
47dbc661 |
634 | printf("Error in read from inotify FD %s.\n", strerror(len)); |
635 | return -1; |
636 | } |
637 | while(offset < len) { |
638 | ievent = (struct inotify_event *)&(buf[offset]); |
639 | for(i=0; i<iwatch_array->num; i++) { |
640 | if(iwatch_array->elem[i].wd == ievent->wd && |
641 | ievent->mask == IN_CREATE) { |
51f9cfd2 |
642 | printf_verbose( |
643 | "inotify wd %u event mask : %u for %s%s\n", |
47dbc661 |
644 | ievent->wd, ievent->mask, |
51f9cfd2 |
645 | iwatch_array->elem[i].path_channel, |
646 | ievent->name); |
47dbc661 |
647 | old_num = fd_pairs->num_pairs; |
648 | strcpy(path_channel, iwatch_array->elem[i].path_channel); |
649 | strcat(path_channel, ievent->name); |
650 | strcpy(path_trace, iwatch_array->elem[i].path_trace); |
651 | strcat(path_trace, ievent->name); |
652 | if(ret = open_buffer_file(ievent->name, path_channel, |
653 | path_trace, fd_pairs)) { |
654 | printf("Error opening buffer file\n"); |
655 | return -1; |
656 | } |
657 | if(ret = map_channels(fd_pairs, old_num, fd_pairs->num_pairs)) { |
658 | printf("Error mapping channel\n"); |
659 | return -1; |
660 | } |
661 | |
662 | } |
663 | } |
664 | offset += sizeof(*ievent) + ievent->len; |
665 | } |
666 | } |
667 | #endif //HAS_INOTIFY |
c3e8c24f |
668 | |
669 | /* read_channels |
22acb617 |
670 | * |
671 | * Thread worker. |
c3e8c24f |
672 | * |
bb01fdc6 |
673 | * Read the debugfs channels and write them in the paired tracefiles. |
c3e8c24f |
674 | * |
675 | * @fd_pairs : paired channels and trace files. |
676 | * |
47dbc661 |
677 | * returns 0 on success, -1 on error. |
c3e8c24f |
678 | * |
679 | * Note that the high priority polled channels are consumed first. We then poll |
680 | * again to see if these channels are still in priority. Only when no |
681 | * high priority channel is left, we start reading low priority channels. |
682 | * |
683 | * Note that a channel is considered high priority when the buffer is almost |
684 | * full. |
685 | */ |
686 | |
d66cc831 |
687 | int read_channels(unsigned long thread_num, struct channel_trace_fd *fd_pairs, |
47dbc661 |
688 | int inotify_fd, struct inotify_watch_array *iwatch_array) |
c3e8c24f |
689 | { |
47dbc661 |
690 | struct pollfd *pollfd = NULL; |
d66cc831 |
691 | int num_pollfd; |
c3e8c24f |
692 | int i,j; |
693 | int num_rdy, num_hup; |
694 | int high_prio; |
22acb617 |
695 | int ret = 0; |
47dbc661 |
696 | int inotify_fds; |
697 | unsigned int old_num; |
c3e8c24f |
698 | |
47dbc661 |
699 | #ifdef HAS_INOTIFY |
700 | inotify_fds = 1; |
701 | #else |
702 | inotify_fds = 0; |
703 | #endif |
704 | |
d66cc831 |
705 | pthread_rwlock_rdlock(&fd_pairs_lock); |
706 | |
47dbc661 |
707 | /* Start polling the FD. Keep one fd for inotify */ |
708 | pollfd = malloc((inotify_fds + fd_pairs->num_pairs) * sizeof(struct pollfd)); |
709 | |
710 | #ifdef HAS_INOTIFY |
711 | pollfd[0].fd = inotify_fd; |
712 | pollfd[0].events = POLLIN|POLLPRI; |
713 | #endif |
9e7dbe44 |
714 | |
715 | for(i=0;i<fd_pairs->num_pairs;i++) { |
47dbc661 |
716 | pollfd[inotify_fds+i].fd = fd_pairs->pair[i].channel; |
717 | pollfd[inotify_fds+i].events = POLLIN|POLLPRI; |
9e7dbe44 |
718 | } |
d66cc831 |
719 | num_pollfd = inotify_fds + fd_pairs->num_pairs; |
720 | |
721 | |
722 | pthread_rwlock_unlock(&fd_pairs_lock); |
723 | |
9e7dbe44 |
724 | while(1) { |
68047576 |
725 | high_prio = 0; |
af4061b2 |
726 | num_hup = 0; |
727 | #ifdef DEBUG |
728 | printf("Press a key for next poll...\n"); |
729 | char buf[1]; |
730 | read(STDIN_FILENO, &buf, 1); |
d66cc831 |
731 | printf("Next poll (polling %d fd) :\n", num_pollfd); |
af4061b2 |
732 | #endif //DEBUG |
47dbc661 |
733 | |
af4061b2 |
734 | /* Have we received a signal ? */ |
735 | if(quit_program) break; |
736 | |
d66cc831 |
737 | num_rdy = poll(pollfd, num_pollfd, -1); |
738 | |
9e7dbe44 |
739 | if(num_rdy == -1) { |
740 | perror("Poll error"); |
af4061b2 |
741 | goto free_fd; |
9e7dbe44 |
742 | } |
743 | |
51f9cfd2 |
744 | printf_verbose("Data received\n"); |
47dbc661 |
745 | #ifdef HAS_INOTIFY |
746 | switch(pollfd[0].revents) { |
747 | case POLLERR: |
51f9cfd2 |
748 | printf_verbose( |
749 | "Error returned in polling inotify fd %d.\n", |
750 | pollfd[0].fd); |
47dbc661 |
751 | break; |
752 | case POLLHUP: |
51f9cfd2 |
753 | printf_verbose( |
754 | "Polling inotify fd %d tells it has hung up.\n", |
755 | pollfd[0].fd); |
47dbc661 |
756 | break; |
757 | case POLLNVAL: |
51f9cfd2 |
758 | printf_verbose( |
759 | "Polling inotify fd %d tells fd is not open.\n", |
760 | pollfd[0].fd); |
47dbc661 |
761 | break; |
762 | case POLLPRI: |
763 | case POLLIN: |
51f9cfd2 |
764 | printf_verbose( |
765 | "Polling inotify fd %d : data ready.\n", |
766 | pollfd[0].fd); |
d66cc831 |
767 | |
768 | pthread_rwlock_wrlock(&fd_pairs_lock); |
47dbc661 |
769 | read_inotify(inotify_fd, fd_pairs, iwatch_array); |
d66cc831 |
770 | pthread_rwlock_unlock(&fd_pairs_lock); |
771 | |
47dbc661 |
772 | break; |
773 | } |
774 | #endif |
9e7dbe44 |
775 | |
d66cc831 |
776 | for(i=inotify_fds;i<num_pollfd;i++) { |
9e7dbe44 |
777 | switch(pollfd[i].revents) { |
778 | case POLLERR: |
51f9cfd2 |
779 | printf_verbose( |
780 | "Error returned in polling fd %d.\n", |
781 | pollfd[i].fd); |
af4061b2 |
782 | num_hup++; |
9e7dbe44 |
783 | break; |
784 | case POLLHUP: |
51f9cfd2 |
785 | printf_verbose( |
786 | "Polling fd %d tells it has hung up.\n", |
787 | pollfd[i].fd); |
af4061b2 |
788 | num_hup++; |
9e7dbe44 |
789 | break; |
790 | case POLLNVAL: |
51f9cfd2 |
791 | printf_verbose( |
792 | "Polling fd %d tells fd is not open.\n", |
793 | pollfd[i].fd); |
af4061b2 |
794 | num_hup++; |
9e7dbe44 |
795 | break; |
796 | case POLLPRI: |
d66cc831 |
797 | pthread_rwlock_rdlock(&fd_pairs_lock); |
47dbc661 |
798 | if(pthread_mutex_trylock(&fd_pairs->pair[i-inotify_fds].mutex) == 0) { |
51f9cfd2 |
799 | printf_verbose( |
800 | "Urgent read on fd %d\n", |
801 | pollfd[i].fd); |
22acb617 |
802 | /* Take care of high priority channels first. */ |
803 | high_prio = 1; |
804 | /* it's ok to have an unavailable subbuffer */ |
47dbc661 |
805 | ret = read_subbuffer(&fd_pairs->pair[i-inotify_fds]); |
63bf9ed1 |
806 | if(ret == EAGAIN) ret = 0; |
b8d28629 |
807 | |
47dbc661 |
808 | ret = pthread_mutex_unlock(&fd_pairs->pair[i-inotify_fds].mutex); |
22acb617 |
809 | if(ret) |
810 | printf("Error in mutex unlock : %s\n", strerror(ret)); |
811 | } |
d66cc831 |
812 | pthread_rwlock_unlock(&fd_pairs_lock); |
9e7dbe44 |
813 | break; |
68047576 |
814 | } |
9e7dbe44 |
815 | } |
47dbc661 |
816 | /* If every buffer FD has hung up, we end the read loop here */ |
d66cc831 |
817 | if(num_hup == num_pollfd - inotify_fds) break; |
9e7dbe44 |
818 | |
68047576 |
819 | if(!high_prio) { |
d66cc831 |
820 | for(i=inotify_fds;i<num_pollfd;i++) { |
68047576 |
821 | switch(pollfd[i].revents) { |
822 | case POLLIN: |
d66cc831 |
823 | pthread_rwlock_rdlock(&fd_pairs_lock); |
47dbc661 |
824 | if(pthread_mutex_trylock(&fd_pairs->pair[i-inotify_fds].mutex) == 0) { |
22acb617 |
825 | /* Take care of low priority channels. */ |
51f9cfd2 |
826 | printf_verbose( |
827 | "Normal read on fd %d\n", |
828 | pollfd[i].fd); |
22acb617 |
829 | /* it's ok to have an unavailable subbuffer */ |
47dbc661 |
830 | ret = read_subbuffer(&fd_pairs->pair[i-inotify_fds]); |
63bf9ed1 |
831 | if(ret == EAGAIN) ret = 0; |
b8d28629 |
832 | |
47dbc661 |
833 | ret = pthread_mutex_unlock(&fd_pairs->pair[i-inotify_fds].mutex); |
22acb617 |
834 | if(ret) |
835 | printf("Error in mutex unlock : %s\n", strerror(ret)); |
836 | } |
d66cc831 |
837 | pthread_rwlock_unlock(&fd_pairs_lock); |
68047576 |
838 | break; |
839 | } |
840 | } |
9e7dbe44 |
841 | } |
842 | |
d66cc831 |
843 | /* Update pollfd array if an entry was added to fd_pairs */ |
844 | pthread_rwlock_rdlock(&fd_pairs_lock); |
845 | if((inotify_fds + fd_pairs->num_pairs) != num_pollfd) { |
846 | pollfd = realloc(pollfd, |
847 | (inotify_fds + fd_pairs->num_pairs) * sizeof(struct pollfd)); |
848 | for(i=num_pollfd-inotify_fds;i<fd_pairs->num_pairs;i++) { |
849 | pollfd[inotify_fds+i].fd = fd_pairs->pair[i].channel; |
850 | pollfd[inotify_fds+i].events = POLLIN|POLLPRI; |
851 | } |
852 | num_pollfd = fd_pairs->num_pairs + inotify_fds; |
853 | } |
854 | pthread_rwlock_unlock(&fd_pairs_lock); |
855 | |
856 | /* NB: If the fd_pairs structure is updated by another thread from this |
857 | * point forward, the current thread will wait in the poll without |
858 | * monitoring the new channel. However, this thread will add the |
859 | * new channel on next poll (and this should not take too much time |
860 | * on a loaded system). |
861 | * |
862 | * This event is quite unlikely and can only occur if a CPU is |
863 | * hot-plugged while multple lttd threads are running. |
864 | */ |
9e7dbe44 |
865 | } |
866 | |
af4061b2 |
867 | free_fd: |
9e7dbe44 |
868 | free(pollfd); |
869 | |
af4061b2 |
870 | end: |
47dbc661 |
871 | return ret; |
6cecb9cf |
872 | } |
873 | |
874 | |
47dbc661 |
875 | void close_channel_trace_pairs(struct channel_trace_fd *fd_pairs, int inotify_fd, |
876 | struct inotify_watch_array *iwatch_array) |
6cecb9cf |
877 | { |
9e7dbe44 |
878 | int i; |
879 | int ret; |
6cecb9cf |
880 | |
9e7dbe44 |
881 | for(i=0;i<fd_pairs->num_pairs;i++) { |
882 | ret = close(fd_pairs->pair[i].channel); |
883 | if(ret == -1) perror("Close error on channel"); |
884 | ret = close(fd_pairs->pair[i].trace); |
885 | if(ret == -1) perror("Close error on trace"); |
886 | } |
887 | free(fd_pairs->pair); |
47dbc661 |
888 | free(iwatch_array->elem); |
889 | } |
890 | |
891 | /* Thread worker */ |
892 | void * thread_main(void *arg) |
893 | { |
d66cc831 |
894 | long ret; |
895 | unsigned long thread_num = (unsigned long)arg; |
896 | |
d61d094a |
897 | ret = pipe(thread_pipe); |
898 | if (ret < 0) { |
899 | perror("Error creating pipe"); |
900 | return (void*)ret; |
901 | } |
d66cc831 |
902 | ret = read_channels(thread_num, &fd_pairs, inotify_fd, &inotify_watch_array); |
d61d094a |
903 | close(thread_pipe[0]); /* close read end */ |
904 | close(thread_pipe[1]); /* close write end */ |
d66cc831 |
905 | return (void*)ret; |
906 | } |
907 | |
908 | |
909 | int channels_init() |
910 | { |
47dbc661 |
911 | int ret = 0; |
47dbc661 |
912 | |
913 | inotify_fd = inotify_init(); |
d66cc831 |
914 | fcntl(inotify_fd, F_SETFL, O_NONBLOCK); |
47dbc661 |
915 | |
916 | if(ret = open_channel_trace_pairs(channel_name, trace_name, &fd_pairs, |
917 | &inotify_fd, &inotify_watch_array)) |
918 | goto close_channel; |
919 | |
920 | if(ret = map_channels(&fd_pairs, 0, fd_pairs.num_pairs)) |
921 | goto close_channel; |
d66cc831 |
922 | return 0; |
47dbc661 |
923 | |
924 | close_channel: |
925 | close_channel_trace_pairs(&fd_pairs, inotify_fd, &inotify_watch_array); |
926 | if(inotify_fd >= 0) |
927 | close(inotify_fd); |
d66cc831 |
928 | return ret; |
6cecb9cf |
929 | } |
930 | |
d66cc831 |
931 | |
6cecb9cf |
932 | int main(int argc, char ** argv) |
933 | { |
c3e8c24f |
934 | int ret = 0; |
af4061b2 |
935 | struct sigaction act; |
22acb617 |
936 | pthread_t *tids; |
d66cc831 |
937 | unsigned long i; |
22acb617 |
938 | void *tret; |
6cecb9cf |
939 | |
940 | ret = parse_arguments(argc, argv); |
941 | |
942 | if(ret != 0) show_arguments(); |
943 | if(ret < 0) return EINVAL; |
944 | if(ret > 0) return 0; |
945 | |
946 | show_info(); |
947 | |
af4061b2 |
948 | /* Connect the signal handlers */ |
949 | act.sa_handler = handler; |
950 | act.sa_flags = 0; |
951 | sigemptyset(&(act.sa_mask)); |
952 | sigaddset(&(act.sa_mask), SIGTERM); |
953 | sigaddset(&(act.sa_mask), SIGQUIT); |
954 | sigaddset(&(act.sa_mask), SIGINT); |
955 | sigaction(SIGTERM, &act, NULL); |
956 | sigaction(SIGQUIT, &act, NULL); |
957 | sigaction(SIGINT, &act, NULL); |
958 | |
d66cc831 |
959 | if(ret = channels_init()) |
960 | return ret; |
961 | |
ebb39a89 |
962 | if(daemon_mode) { |
963 | ret = daemon(0, 0); |
964 | |
965 | if(ret == -1) { |
966 | perror("An error occured while daemonizing."); |
967 | exit(-1); |
968 | } |
969 | } |
970 | |
22acb617 |
971 | tids = malloc(sizeof(pthread_t) * num_threads); |
972 | for(i=0; i<num_threads; i++) { |
d3b6d84f |
973 | |
47dbc661 |
974 | ret = pthread_create(&tids[i], NULL, thread_main, (void*)i); |
22acb617 |
975 | if(ret) { |
976 | perror("Error creating thread"); |
977 | break; |
978 | } |
979 | } |
6cecb9cf |
980 | |
22acb617 |
981 | for(i=0; i<num_threads; i++) { |
982 | ret = pthread_join(tids[i], &tret); |
983 | if(ret) { |
984 | perror("Error joining thread"); |
985 | break; |
986 | } |
d66cc831 |
987 | if((long)tret != 0) { |
988 | printf("Error %s occured in thread %u\n", |
989 | strerror((long)tret), i); |
22acb617 |
990 | } |
991 | } |
992 | |
993 | free(tids); |
d66cc831 |
994 | ret = unmap_channels(&fd_pairs); |
995 | close_channel_trace_pairs(&fd_pairs, inotify_fd, &inotify_watch_array); |
996 | if(inotify_fd >= 0) |
997 | close(inotify_fd); |
22acb617 |
998 | |
6cecb9cf |
999 | return ret; |
1000 | } |