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 | * |
31482529 |
8 | * CPU hot-plugging is supported using inotify. |
617de8e1 |
9 | * |
10 | * Copyright 2005 - |
11 | * Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> |
12 | */ |
13 | |
0bb647f5 |
14 | #ifdef HAVE_CONFIG_H |
469206ed |
15 | #include <config.h> |
0bb647f5 |
16 | #endif |
17 | |
e54e1d5d |
18 | #define _REENTRANT |
0bb647f5 |
19 | #define _GNU_SOURCE |
e54e1d5d |
20 | #include <features.h> |
617de8e1 |
21 | #include <stdio.h> |
1d483eea |
22 | #include <unistd.h> |
617de8e1 |
23 | #include <errno.h> |
24 | #include <sys/types.h> |
25 | #include <sys/stat.h> |
617de8e1 |
26 | #include <stdlib.h> |
27 | #include <dirent.h> |
28 | #include <string.h> |
90ccaa9a |
29 | #include <fcntl.h> |
30 | #include <sys/poll.h> |
1d483eea |
31 | #include <sys/mman.h> |
32 | #include <signal.h> |
e54e1d5d |
33 | #include <pthread.h> |
357915bb |
34 | #include <sys/syscall.h> |
35 | #include <unistd.h> |
36 | #include <asm/ioctls.h> |
37 | |
38 | #include <linux/version.h> |
1d483eea |
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. */ |
766632ac |
45 | #define RELAY_GET_SUBBUF _IOR(0xF5, 0x00,__u32) |
1d483eea |
46 | /* Release the oldest reserved (by "get") sub buffer. */ |
766632ac |
47 | #define RELAY_PUT_SUBBUF _IOW(0xF5, 0x01,__u32) |
1d483eea |
48 | /* returns the number of sub buffers in the per cpu channel. */ |
766632ac |
49 | #define RELAY_GET_N_SUBBUFS _IOR(0xF5, 0x02,__u32) |
1d483eea |
50 | /* returns the size of the sub buffers. */ |
766632ac |
51 | #define RELAY_GET_SUBBUF_SIZE _IOR(0xF5, 0x03,__u32) |
1d483eea |
52 | |
357915bb |
53 | #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,14) |
7967f7c3 |
54 | #include <sys/inotify.h> |
8d91577f |
55 | #if 0 /* should now be provided by libc. */ |
357915bb |
56 | /* From the inotify-tools 2.6 package */ |
57 | static inline int inotify_init (void) |
58 | { |
59 | return syscall (__NR_inotify_init); |
60 | } |
61 | |
62 | static inline int inotify_add_watch (int fd, const char *name, __u32 mask) |
63 | { |
64 | return syscall (__NR_inotify_add_watch, fd, name, mask); |
65 | } |
66 | |
67 | static inline int inotify_rm_watch (int fd, __u32 wd) |
68 | { |
69 | return syscall (__NR_inotify_rm_watch, fd, wd); |
70 | } |
8d91577f |
71 | #endif //0 |
357915bb |
72 | #define HAS_INOTIFY |
73 | #else |
74 | static inline int inotify_init (void) |
75 | { |
76 | return -1; |
77 | } |
1d483eea |
78 | |
357915bb |
79 | static inline int inotify_add_watch (int fd, const char *name, __u32 mask) |
80 | { |
81 | return 0; |
82 | } |
83 | |
84 | static inline int inotify_rm_watch (int fd, __u32 wd) |
85 | { |
86 | return 0; |
87 | } |
88 | #undef HAS_INOTIFY |
89 | #endif |
617de8e1 |
90 | |
91 | enum { |
92 | GET_SUBBUF, |
93 | PUT_SUBBUF, |
94 | GET_N_BUBBUFS, |
95 | GET_SUBBUF_SIZE |
96 | }; |
97 | |
98 | struct fd_pair { |
99 | int channel; |
100 | int trace; |
1d483eea |
101 | unsigned int n_subbufs; |
102 | unsigned int subbuf_size; |
103 | void *mmap; |
5ffb77aa |
104 | pthread_mutex_t mutex; |
617de8e1 |
105 | }; |
106 | |
107 | struct channel_trace_fd { |
108 | struct fd_pair *pair; |
109 | int num_pairs; |
110 | }; |
111 | |
357915bb |
112 | struct inotify_watch { |
113 | int wd; |
114 | char path_channel[PATH_MAX]; |
115 | char path_trace[PATH_MAX]; |
116 | }; |
117 | |
118 | struct inotify_watch_array { |
119 | struct inotify_watch *elem; |
120 | int num; |
121 | }; |
122 | |
f01152ea |
123 | static __thread int thread_pipe[2]; |
31482529 |
124 | |
125 | struct channel_trace_fd fd_pairs = { NULL, 0 }; |
126 | int inotify_fd = -1; |
127 | struct inotify_watch_array inotify_watch_array = { NULL, 0 }; |
128 | |
129 | /* protects fd_pairs and inotify_watch_array */ |
130 | pthread_rwlock_t fd_pairs_lock = PTHREAD_RWLOCK_INITIALIZER; |
131 | |
132 | |
89565b43 |
133 | static char *trace_name = NULL; |
134 | static char *channel_name = NULL; |
135 | static int daemon_mode = 0; |
136 | static int append_mode = 0; |
137 | static unsigned long num_threads = 1; |
1d483eea |
138 | volatile static int quit_program = 0; /* For signal handler */ |
89565b43 |
139 | static int dump_flight_only = 0; |
140 | static int dump_normal_only = 0; |
083518b7 |
141 | static int verbose_mode = 0; |
142 | |
143 | #define printf_verbose(fmt, args...) \ |
144 | do { \ |
145 | if (verbose_mode) \ |
146 | printf(fmt, ##args); \ |
147 | } while (0) |
617de8e1 |
148 | |
149 | /* Args : |
150 | * |
151 | * -t directory Directory name of the trace to write to. Will be created. |
c2ffa20f |
152 | * -c directory Root directory of the debugfs trace channels. |
617de8e1 |
153 | * -d Run in background (daemon). |
083518b7 |
154 | * -a Trace append mode. |
155 | * -s Send SIGUSR1 to parent when ready for IO. |
617de8e1 |
156 | */ |
157 | void show_arguments(void) |
158 | { |
159 | printf("Please use the following arguments :\n"); |
160 | printf("\n"); |
161 | printf("-t directory Directory name of the trace to write to.\n" |
162 | " It will be created.\n"); |
c2ffa20f |
163 | printf("-c directory Root directory of the debugfs trace channels.\n"); |
617de8e1 |
164 | printf("-d Run in background (daemon).\n"); |
90ccaa9a |
165 | printf("-a Append to an possibly existing trace.\n"); |
5ffb77aa |
166 | printf("-N Number of threads to start.\n"); |
89565b43 |
167 | printf("-f Dump only flight recorder channels.\n"); |
168 | printf("-n Dump only normal channels.\n"); |
083518b7 |
169 | printf("-v Verbose mode.\n"); |
617de8e1 |
170 | printf("\n"); |
171 | } |
172 | |
173 | |
174 | /* parse_arguments |
175 | * |
176 | * Parses the command line arguments. |
177 | * |
178 | * Returns 1 if the arguments were correct, but doesn't ask for program |
179 | * continuation. Returns -1 if the arguments are incorrect, or 0 if OK. |
180 | */ |
181 | int parse_arguments(int argc, char **argv) |
182 | { |
183 | int ret = 0; |
184 | int argn = 1; |
185 | |
186 | if(argc == 2) { |
187 | if(strcmp(argv[1], "-h") == 0) { |
188 | return 1; |
189 | } |
190 | } |
191 | |
90ccaa9a |
192 | while(argn < argc) { |
617de8e1 |
193 | |
194 | switch(argv[argn][0]) { |
195 | case '-': |
196 | switch(argv[argn][1]) { |
197 | case 't': |
90ccaa9a |
198 | if(argn+1 < argc) { |
199 | trace_name = argv[argn+1]; |
200 | argn++; |
201 | } |
617de8e1 |
202 | break; |
203 | case 'c': |
90ccaa9a |
204 | if(argn+1 < argc) { |
205 | channel_name = argv[argn+1]; |
206 | argn++; |
207 | } |
617de8e1 |
208 | break; |
209 | case 'd': |
210 | daemon_mode = 1; |
211 | break; |
90ccaa9a |
212 | case 'a': |
213 | append_mode = 1; |
214 | break; |
5ffb77aa |
215 | case 'N': |
e54e1d5d |
216 | if(argn+1 < argc) { |
217 | num_threads = strtoul(argv[argn+1], NULL, 0); |
218 | argn++; |
219 | } |
220 | break; |
89565b43 |
221 | case 'f': |
222 | dump_flight_only = 1; |
223 | break; |
224 | case 'n': |
225 | dump_normal_only = 1; |
226 | break; |
083518b7 |
227 | case 'v': |
228 | verbose_mode = 1; |
229 | break; |
617de8e1 |
230 | default: |
231 | printf("Invalid argument '%s'.\n", argv[argn]); |
232 | printf("\n"); |
233 | ret = -1; |
234 | } |
235 | break; |
236 | default: |
237 | printf("Invalid argument '%s'.\n", argv[argn]); |
238 | printf("\n"); |
239 | ret = -1; |
240 | } |
241 | argn++; |
242 | } |
243 | |
244 | if(trace_name == NULL) { |
245 | printf("Please specify a trace name.\n"); |
246 | printf("\n"); |
247 | ret = -1; |
248 | } |
249 | |
250 | if(channel_name == NULL) { |
251 | printf("Please specify a channel name.\n"); |
252 | printf("\n"); |
253 | ret = -1; |
254 | } |
255 | |
256 | return ret; |
257 | } |
258 | |
259 | void show_info(void) |
260 | { |
15061ecb |
261 | printf("Linux Trace Toolkit Trace Daemon " VERSION "\n"); |
617de8e1 |
262 | printf("\n"); |
c2ffa20f |
263 | printf("Reading from debugfs directory : %s\n", channel_name); |
617de8e1 |
264 | printf("Writing to trace directory : %s\n", trace_name); |
265 | printf("\n"); |
266 | } |
267 | |
268 | |
1d483eea |
269 | /* signal handling */ |
270 | |
271 | static void handler(int signo) |
272 | { |
273 | printf("Signal %d received : exiting cleanly\n", signo); |
274 | quit_program = 1; |
275 | } |
276 | |
277 | |
357915bb |
278 | int open_buffer_file(char *filename, char *path_channel, char *path_trace, |
279 | struct channel_trace_fd *fd_pairs) |
280 | { |
281 | int open_ret = 0; |
282 | int ret = 0; |
283 | struct stat stat_buf; |
284 | |
285 | if(strncmp(filename, "flight-", sizeof("flight-")-1) != 0) { |
286 | if(dump_flight_only) { |
083518b7 |
287 | printf_verbose("Skipping normal channel %s\n", |
288 | path_channel); |
357915bb |
289 | return 0; |
290 | } |
291 | } else { |
292 | if(dump_normal_only) { |
083518b7 |
293 | printf_verbose("Skipping flight channel %s\n", |
294 | path_channel); |
357915bb |
295 | return 0; |
296 | } |
297 | } |
083518b7 |
298 | printf_verbose("Opening file.\n"); |
357915bb |
299 | |
300 | fd_pairs->pair = realloc(fd_pairs->pair, |
301 | ++fd_pairs->num_pairs * sizeof(struct fd_pair)); |
302 | |
303 | /* Open the channel in read mode */ |
304 | fd_pairs->pair[fd_pairs->num_pairs-1].channel = |
305 | open(path_channel, O_RDONLY | O_NONBLOCK); |
306 | if(fd_pairs->pair[fd_pairs->num_pairs-1].channel == -1) { |
307 | perror(path_channel); |
308 | fd_pairs->num_pairs--; |
309 | return 0; /* continue */ |
310 | } |
311 | /* Open the trace in write mode, only append if append_mode */ |
312 | ret = stat(path_trace, &stat_buf); |
313 | if(ret == 0) { |
314 | if(append_mode) { |
083518b7 |
315 | printf_verbose("Appending to file %s as requested\n", |
316 | path_trace); |
357915bb |
317 | |
318 | fd_pairs->pair[fd_pairs->num_pairs-1].trace = |
42e99028 |
319 | open(path_trace, O_WRONLY, |
357915bb |
320 | S_IRWXU|S_IRWXG|S_IRWXO); |
357915bb |
321 | if(fd_pairs->pair[fd_pairs->num_pairs-1].trace == -1) { |
322 | perror(path_trace); |
323 | } |
42e99028 |
324 | ret = lseek(fd_pairs->pair[fd_pairs->num_pairs-1].trace, |
325 | 0, SEEK_END); |
326 | if (ret < 0) { |
327 | perror(path_trace); |
328 | } |
357915bb |
329 | } else { |
330 | printf("File %s exists, cannot open. Try append mode.\n", path_trace); |
331 | open_ret = -1; |
332 | goto end; |
333 | } |
334 | } else { |
335 | if(errno == ENOENT) { |
336 | fd_pairs->pair[fd_pairs->num_pairs-1].trace = |
337 | open(path_trace, O_WRONLY|O_CREAT|O_EXCL, |
338 | S_IRWXU|S_IRWXG|S_IRWXO); |
339 | if(fd_pairs->pair[fd_pairs->num_pairs-1].trace == -1) { |
340 | perror(path_trace); |
341 | } |
342 | } |
343 | } |
344 | end: |
345 | return open_ret; |
346 | } |
1d483eea |
347 | |
617de8e1 |
348 | int open_channel_trace_pairs(char *subchannel_name, char *subtrace_name, |
357915bb |
349 | struct channel_trace_fd *fd_pairs, int *inotify_fd, |
350 | struct inotify_watch_array *iwatch_array) |
617de8e1 |
351 | { |
352 | DIR *channel_dir = opendir(subchannel_name); |
353 | struct dirent *entry; |
354 | struct stat stat_buf; |
355 | int ret; |
356 | char path_channel[PATH_MAX]; |
357 | int path_channel_len; |
358 | char *path_channel_ptr; |
359 | char path_trace[PATH_MAX]; |
360 | int path_trace_len; |
361 | char *path_trace_ptr; |
002f91bb |
362 | int open_ret = 0; |
617de8e1 |
363 | |
364 | if(channel_dir == NULL) { |
365 | perror(subchannel_name); |
d304b1dd |
366 | open_ret = ENOENT; |
002f91bb |
367 | goto end; |
617de8e1 |
368 | } |
369 | |
083518b7 |
370 | printf_verbose("Creating trace subdirectory %s\n", subtrace_name); |
617de8e1 |
371 | ret = mkdir(subtrace_name, S_IRWXU|S_IRWXG|S_IRWXO); |
372 | if(ret == -1) { |
b1e3e7c7 |
373 | if(errno != EEXIST) { |
90ccaa9a |
374 | perror(subtrace_name); |
002f91bb |
375 | open_ret = -1; |
d304b1dd |
376 | goto end; |
90ccaa9a |
377 | } |
617de8e1 |
378 | } |
379 | |
380 | strncpy(path_channel, subchannel_name, PATH_MAX-1); |
381 | path_channel_len = strlen(path_channel); |
382 | path_channel[path_channel_len] = '/'; |
383 | path_channel_len++; |
384 | path_channel_ptr = path_channel + path_channel_len; |
385 | |
386 | strncpy(path_trace, subtrace_name, PATH_MAX-1); |
387 | path_trace_len = strlen(path_trace); |
388 | path_trace[path_trace_len] = '/'; |
389 | path_trace_len++; |
390 | path_trace_ptr = path_trace + path_trace_len; |
391 | |
357915bb |
392 | #ifdef HAS_INOTIFY |
393 | iwatch_array->elem = realloc(iwatch_array->elem, |
394 | ++iwatch_array->num * sizeof(struct inotify_watch)); |
395 | |
083518b7 |
396 | printf_verbose("Adding inotify for channel %s\n", path_channel); |
357915bb |
397 | iwatch_array->elem[iwatch_array->num-1].wd = inotify_add_watch(*inotify_fd, path_channel, IN_CREATE); |
398 | strcpy(iwatch_array->elem[iwatch_array->num-1].path_channel, path_channel); |
399 | strcpy(iwatch_array->elem[iwatch_array->num-1].path_trace, path_trace); |
083518b7 |
400 | printf_verbose("Added inotify for channel %s, wd %u\n", |
401 | iwatch_array->elem[iwatch_array->num-1].path_channel, |
357915bb |
402 | iwatch_array->elem[iwatch_array->num-1].wd); |
403 | #endif |
404 | |
617de8e1 |
405 | while((entry = readdir(channel_dir)) != NULL) { |
406 | |
407 | if(entry->d_name[0] == '.') continue; |
408 | |
409 | strncpy(path_channel_ptr, entry->d_name, PATH_MAX - path_channel_len); |
410 | strncpy(path_trace_ptr, entry->d_name, PATH_MAX - path_trace_len); |
411 | |
412 | ret = stat(path_channel, &stat_buf); |
413 | if(ret == -1) { |
414 | perror(path_channel); |
415 | continue; |
416 | } |
417 | |
083518b7 |
418 | printf_verbose("Channel file : %s\n", path_channel); |
617de8e1 |
419 | |
420 | if(S_ISDIR(stat_buf.st_mode)) { |
421 | |
083518b7 |
422 | printf_verbose("Entering channel subdirectory...\n"); |
357915bb |
423 | ret = open_channel_trace_pairs(path_channel, path_trace, fd_pairs, |
424 | inotify_fd, iwatch_array); |
617de8e1 |
425 | if(ret < 0) continue; |
90ccaa9a |
426 | } else if(S_ISREG(stat_buf.st_mode)) { |
357915bb |
427 | open_ret = open_buffer_file(entry->d_name, path_channel, path_trace, |
428 | fd_pairs); |
429 | if(open_ret) |
430 | goto end; |
617de8e1 |
431 | } |
617de8e1 |
432 | } |
433 | |
d304b1dd |
434 | end: |
617de8e1 |
435 | closedir(channel_dir); |
436 | |
d304b1dd |
437 | return open_ret; |
617de8e1 |
438 | } |
439 | |
1d483eea |
440 | |
441 | int read_subbuffer(struct fd_pair *pair) |
442 | { |
f01152ea |
443 | unsigned int consumed_old; |
444 | int err; |
445 | long ret; |
4e1c69e6 |
446 | unsigned long len; |
447 | off_t offset; |
1d483eea |
448 | |
449 | |
f01152ea |
450 | err = ioctl(pair->channel, RELAY_GET_SUBBUF, &consumed_old); |
083518b7 |
451 | printf_verbose("cookie : %u\n", consumed_old); |
469206ed |
452 | if(err != 0) { |
5ffb77aa |
453 | ret = errno; |
30478a4d |
454 | perror("Reserving sub buffer failed (everything is normal, it is due to concurrency)"); |
469206ed |
455 | goto get_error; |
1d483eea |
456 | } |
f01152ea |
457 | #if 0 |
469206ed |
458 | err = TEMP_FAILURE_RETRY(write(pair->trace, |
e4bed64a |
459 | pair->mmap |
460 | + (consumed_old & ((pair->n_subbufs * pair->subbuf_size)-1)), |
1d483eea |
461 | pair->subbuf_size)); |
469206ed |
462 | |
463 | if(err < 0) { |
5ffb77aa |
464 | ret = errno; |
1d483eea |
465 | perror("Error in writing to file"); |
469206ed |
466 | goto write_error; |
1d483eea |
467 | } |
f01152ea |
468 | #endif //0 |
469 | len = pair->subbuf_size; |
470 | offset = 0; |
471 | while (len > 0) { |
4e1c69e6 |
472 | printf_verbose("splice chan to pipe offset %lu\n", |
473 | (unsigned long)offset); |
f01152ea |
474 | ret = splice(pair->channel, &offset, thread_pipe[1], NULL, |
4b6ff6ef |
475 | len, SPLICE_F_MOVE | SPLICE_F_MORE); |
083518b7 |
476 | printf_verbose("splice chan to pipe ret %ld\n", ret); |
f01152ea |
477 | if (ret < 0) { |
478 | perror("Error in relay splice"); |
479 | goto write_error; |
480 | } |
481 | ret = splice(thread_pipe[0], NULL, pair->trace, NULL, |
4b6ff6ef |
482 | ret, SPLICE_F_MOVE | SPLICE_F_MORE); |
083518b7 |
483 | printf_verbose("splice pipe to file %ld\n", ret); |
f01152ea |
484 | if (ret < 0) { |
485 | perror("Error in file splice"); |
486 | goto write_error; |
487 | } |
488 | len -= ret; |
489 | } |
490 | |
a7eb8aa2 |
491 | #if 0 |
492 | err = fsync(pair->trace); |
493 | if(err < 0) { |
494 | ret = errno; |
495 | perror("Error in writing to file"); |
496 | goto write_error; |
497 | } |
498 | #endif //0 |
469206ed |
499 | write_error: |
f01152ea |
500 | ret = 0; |
c2ffa20f |
501 | err = ioctl(pair->channel, RELAY_PUT_SUBBUF, &consumed_old); |
469206ed |
502 | if(err != 0) { |
5ffb77aa |
503 | ret = errno; |
30478a4d |
504 | if(errno == EFAULT) { |
5ffb77aa |
505 | perror("Error in unreserving sub buffer\n"); |
30478a4d |
506 | } else if(errno == EIO) { |
4f31148b |
507 | perror("Reader has been pushed by the writer, last subbuffer corrupted."); |
ec8cce5a |
508 | /* FIXME : we may delete the last written buffer if we wish. */ |
4f31148b |
509 | } |
469206ed |
510 | goto get_error; |
1d483eea |
511 | } |
512 | |
469206ed |
513 | get_error: |
514 | return ret; |
1d483eea |
515 | } |
516 | |
517 | |
357915bb |
518 | int map_channels(struct channel_trace_fd *fd_pairs, |
519 | int idx_begin, int idx_end) |
617de8e1 |
520 | { |
1d483eea |
521 | int i,j; |
e54e1d5d |
522 | int ret=0; |
1d483eea |
523 | |
469206ed |
524 | if(fd_pairs->num_pairs <= 0) { |
525 | printf("No channel to read\n"); |
526 | goto end; |
527 | } |
528 | |
1d483eea |
529 | /* Get the subbuf sizes and number */ |
530 | |
357915bb |
531 | for(i=idx_begin;i<idx_end;i++) { |
1d483eea |
532 | struct fd_pair *pair = &fd_pairs->pair[i]; |
90ccaa9a |
533 | |
c2ffa20f |
534 | ret = ioctl(pair->channel, RELAY_GET_N_SUBBUFS, |
1d483eea |
535 | &pair->n_subbufs); |
536 | if(ret != 0) { |
537 | perror("Error in getting the number of subbuffers"); |
538 | goto end; |
539 | } |
c2ffa20f |
540 | ret = ioctl(pair->channel, RELAY_GET_SUBBUF_SIZE, |
1d483eea |
541 | &pair->subbuf_size); |
542 | if(ret != 0) { |
543 | perror("Error in getting the size of the subbuffers"); |
544 | goto end; |
545 | } |
5ffb77aa |
546 | ret = pthread_mutex_init(&pair->mutex, NULL); /* Fast mutex */ |
547 | if(ret != 0) { |
548 | perror("Error in mutex init"); |
549 | goto end; |
550 | } |
1d483eea |
551 | } |
552 | |
f01152ea |
553 | #if 0 |
1d483eea |
554 | /* Mmap each FD */ |
357915bb |
555 | for(i=idx_begin;i<idx_end;i++) { |
1d483eea |
556 | struct fd_pair *pair = &fd_pairs->pair[i]; |
557 | |
558 | pair->mmap = mmap(0, pair->subbuf_size * pair->n_subbufs, PROT_READ, |
559 | MAP_SHARED, pair->channel, 0); |
560 | if(pair->mmap == MAP_FAILED) { |
561 | perror("Mmap error"); |
562 | goto munmap; |
563 | } |
564 | } |
565 | |
5ffb77aa |
566 | goto end; /* success */ |
1d483eea |
567 | |
e54e1d5d |
568 | /* Error handling */ |
569 | /* munmap only the successfully mmapped indexes */ |
570 | munmap: |
571 | /* Munmap each FD */ |
357915bb |
572 | for(j=idx_begin;j<i;j++) { |
e54e1d5d |
573 | struct fd_pair *pair = &fd_pairs->pair[j]; |
574 | int err_ret; |
575 | |
576 | err_ret = munmap(pair->mmap, pair->subbuf_size * pair->n_subbufs); |
577 | if(err_ret != 0) { |
578 | perror("Error in munmap"); |
579 | } |
580 | ret |= err_ret; |
581 | } |
582 | |
f01152ea |
583 | #endif //0 |
e54e1d5d |
584 | end: |
585 | return ret; |
e54e1d5d |
586 | } |
587 | |
e54e1d5d |
588 | int unmap_channels(struct channel_trace_fd *fd_pairs) |
589 | { |
590 | int j; |
591 | int ret=0; |
592 | |
593 | /* Munmap each FD */ |
594 | for(j=0;j<fd_pairs->num_pairs;j++) { |
595 | struct fd_pair *pair = &fd_pairs->pair[j]; |
596 | int err_ret; |
597 | |
f01152ea |
598 | #if 0 |
e54e1d5d |
599 | err_ret = munmap(pair->mmap, pair->subbuf_size * pair->n_subbufs); |
600 | if(err_ret != 0) { |
601 | perror("Error in munmap"); |
602 | } |
603 | ret |= err_ret; |
f01152ea |
604 | #endif //0 |
5ffb77aa |
605 | err_ret = pthread_mutex_destroy(&pair->mutex); |
606 | if(err_ret != 0) { |
607 | perror("Error in mutex destroy"); |
608 | } |
609 | ret |= err_ret; |
e54e1d5d |
610 | } |
611 | |
612 | return ret; |
613 | } |
614 | |
357915bb |
615 | #ifdef HAS_INOTIFY |
616 | /* Inotify event arrived. |
617 | * |
618 | * Only support add file for now. |
619 | */ |
620 | |
621 | int read_inotify(int inotify_fd, |
622 | struct channel_trace_fd *fd_pairs, |
623 | struct inotify_watch_array *iwatch_array) |
624 | { |
625 | char buf[sizeof(struct inotify_event) + PATH_MAX]; |
626 | char path_channel[PATH_MAX]; |
627 | char path_trace[PATH_MAX]; |
628 | ssize_t len; |
629 | struct inotify_event *ievent; |
630 | size_t offset; |
631 | unsigned int i; |
632 | int ret; |
633 | int old_num; |
634 | |
635 | offset = 0; |
636 | len = read(inotify_fd, buf, sizeof(struct inotify_event) + PATH_MAX); |
637 | if(len < 0) { |
31482529 |
638 | |
639 | if(errno == EAGAIN) |
640 | return 0; /* another thread got the data before us */ |
641 | |
357915bb |
642 | printf("Error in read from inotify FD %s.\n", strerror(len)); |
643 | return -1; |
644 | } |
645 | while(offset < len) { |
646 | ievent = (struct inotify_event *)&(buf[offset]); |
647 | for(i=0; i<iwatch_array->num; i++) { |
648 | if(iwatch_array->elem[i].wd == ievent->wd && |
649 | ievent->mask == IN_CREATE) { |
083518b7 |
650 | printf_verbose( |
651 | "inotify wd %u event mask : %u for %s%s\n", |
357915bb |
652 | ievent->wd, ievent->mask, |
083518b7 |
653 | iwatch_array->elem[i].path_channel, |
654 | ievent->name); |
357915bb |
655 | old_num = fd_pairs->num_pairs; |
656 | strcpy(path_channel, iwatch_array->elem[i].path_channel); |
657 | strcat(path_channel, ievent->name); |
658 | strcpy(path_trace, iwatch_array->elem[i].path_trace); |
659 | strcat(path_trace, ievent->name); |
660 | if(ret = open_buffer_file(ievent->name, path_channel, |
661 | path_trace, fd_pairs)) { |
662 | printf("Error opening buffer file\n"); |
663 | return -1; |
664 | } |
665 | if(ret = map_channels(fd_pairs, old_num, fd_pairs->num_pairs)) { |
666 | printf("Error mapping channel\n"); |
667 | return -1; |
668 | } |
669 | |
670 | } |
671 | } |
672 | offset += sizeof(*ievent) + ievent->len; |
673 | } |
674 | } |
675 | #endif //HAS_INOTIFY |
e54e1d5d |
676 | |
677 | /* read_channels |
5ffb77aa |
678 | * |
679 | * Thread worker. |
e54e1d5d |
680 | * |
c2ffa20f |
681 | * Read the debugfs channels and write them in the paired tracefiles. |
e54e1d5d |
682 | * |
683 | * @fd_pairs : paired channels and trace files. |
684 | * |
357915bb |
685 | * returns 0 on success, -1 on error. |
e54e1d5d |
686 | * |
687 | * Note that the high priority polled channels are consumed first. We then poll |
688 | * again to see if these channels are still in priority. Only when no |
689 | * high priority channel is left, we start reading low priority channels. |
690 | * |
691 | * Note that a channel is considered high priority when the buffer is almost |
692 | * full. |
693 | */ |
694 | |
31482529 |
695 | int read_channels(unsigned long thread_num, struct channel_trace_fd *fd_pairs, |
357915bb |
696 | int inotify_fd, struct inotify_watch_array *iwatch_array) |
e54e1d5d |
697 | { |
357915bb |
698 | struct pollfd *pollfd = NULL; |
31482529 |
699 | int num_pollfd; |
e54e1d5d |
700 | int i,j; |
701 | int num_rdy, num_hup; |
702 | int high_prio; |
5ffb77aa |
703 | int ret = 0; |
357915bb |
704 | int inotify_fds; |
705 | unsigned int old_num; |
e54e1d5d |
706 | |
357915bb |
707 | #ifdef HAS_INOTIFY |
708 | inotify_fds = 1; |
709 | #else |
710 | inotify_fds = 0; |
711 | #endif |
712 | |
31482529 |
713 | pthread_rwlock_rdlock(&fd_pairs_lock); |
714 | |
357915bb |
715 | /* Start polling the FD. Keep one fd for inotify */ |
716 | pollfd = malloc((inotify_fds + fd_pairs->num_pairs) * sizeof(struct pollfd)); |
717 | |
718 | #ifdef HAS_INOTIFY |
719 | pollfd[0].fd = inotify_fd; |
720 | pollfd[0].events = POLLIN|POLLPRI; |
721 | #endif |
90ccaa9a |
722 | |
723 | for(i=0;i<fd_pairs->num_pairs;i++) { |
357915bb |
724 | pollfd[inotify_fds+i].fd = fd_pairs->pair[i].channel; |
725 | pollfd[inotify_fds+i].events = POLLIN|POLLPRI; |
90ccaa9a |
726 | } |
31482529 |
727 | num_pollfd = inotify_fds + fd_pairs->num_pairs; |
728 | |
729 | |
730 | pthread_rwlock_unlock(&fd_pairs_lock); |
731 | |
90ccaa9a |
732 | while(1) { |
4f45ea55 |
733 | high_prio = 0; |
1d483eea |
734 | num_hup = 0; |
735 | #ifdef DEBUG |
736 | printf("Press a key for next poll...\n"); |
737 | char buf[1]; |
738 | read(STDIN_FILENO, &buf, 1); |
31482529 |
739 | printf("Next poll (polling %d fd) :\n", num_pollfd); |
1d483eea |
740 | #endif //DEBUG |
357915bb |
741 | |
1d483eea |
742 | /* Have we received a signal ? */ |
743 | if(quit_program) break; |
744 | |
31482529 |
745 | num_rdy = poll(pollfd, num_pollfd, -1); |
746 | |
90ccaa9a |
747 | if(num_rdy == -1) { |
748 | perror("Poll error"); |
1d483eea |
749 | goto free_fd; |
90ccaa9a |
750 | } |
751 | |
083518b7 |
752 | printf_verbose("Data received\n"); |
357915bb |
753 | #ifdef HAS_INOTIFY |
754 | switch(pollfd[0].revents) { |
755 | case POLLERR: |
083518b7 |
756 | printf_verbose( |
757 | "Error returned in polling inotify fd %d.\n", |
758 | pollfd[0].fd); |
357915bb |
759 | break; |
760 | case POLLHUP: |
083518b7 |
761 | printf_verbose( |
762 | "Polling inotify fd %d tells it has hung up.\n", |
763 | pollfd[0].fd); |
357915bb |
764 | break; |
765 | case POLLNVAL: |
083518b7 |
766 | printf_verbose( |
767 | "Polling inotify fd %d tells fd is not open.\n", |
768 | pollfd[0].fd); |
357915bb |
769 | break; |
770 | case POLLPRI: |
771 | case POLLIN: |
083518b7 |
772 | printf_verbose( |
773 | "Polling inotify fd %d : data ready.\n", |
774 | pollfd[0].fd); |
31482529 |
775 | |
776 | pthread_rwlock_wrlock(&fd_pairs_lock); |
357915bb |
777 | read_inotify(inotify_fd, fd_pairs, iwatch_array); |
31482529 |
778 | pthread_rwlock_unlock(&fd_pairs_lock); |
779 | |
357915bb |
780 | break; |
781 | } |
782 | #endif |
90ccaa9a |
783 | |
31482529 |
784 | for(i=inotify_fds;i<num_pollfd;i++) { |
90ccaa9a |
785 | switch(pollfd[i].revents) { |
786 | case POLLERR: |
083518b7 |
787 | printf_verbose( |
788 | "Error returned in polling fd %d.\n", |
789 | pollfd[i].fd); |
1d483eea |
790 | num_hup++; |
90ccaa9a |
791 | break; |
792 | case POLLHUP: |
083518b7 |
793 | printf_verbose( |
794 | "Polling fd %d tells it has hung up.\n", |
795 | pollfd[i].fd); |
1d483eea |
796 | num_hup++; |
90ccaa9a |
797 | break; |
798 | case POLLNVAL: |
083518b7 |
799 | printf_verbose( |
800 | "Polling fd %d tells fd is not open.\n", |
801 | pollfd[i].fd); |
1d483eea |
802 | num_hup++; |
90ccaa9a |
803 | break; |
804 | case POLLPRI: |
31482529 |
805 | pthread_rwlock_rdlock(&fd_pairs_lock); |
357915bb |
806 | if(pthread_mutex_trylock(&fd_pairs->pair[i-inotify_fds].mutex) == 0) { |
083518b7 |
807 | printf_verbose( |
808 | "Urgent read on fd %d\n", |
809 | pollfd[i].fd); |
5ffb77aa |
810 | /* Take care of high priority channels first. */ |
811 | high_prio = 1; |
812 | /* it's ok to have an unavailable subbuffer */ |
357915bb |
813 | ret = read_subbuffer(&fd_pairs->pair[i-inotify_fds]); |
30478a4d |
814 | if(ret == EAGAIN) ret = 0; |
cdad9787 |
815 | |
357915bb |
816 | ret = pthread_mutex_unlock(&fd_pairs->pair[i-inotify_fds].mutex); |
5ffb77aa |
817 | if(ret) |
818 | printf("Error in mutex unlock : %s\n", strerror(ret)); |
819 | } |
31482529 |
820 | pthread_rwlock_unlock(&fd_pairs_lock); |
90ccaa9a |
821 | break; |
4f45ea55 |
822 | } |
90ccaa9a |
823 | } |
357915bb |
824 | /* If every buffer FD has hung up, we end the read loop here */ |
31482529 |
825 | if(num_hup == num_pollfd - inotify_fds) break; |
90ccaa9a |
826 | |
4f45ea55 |
827 | if(!high_prio) { |
31482529 |
828 | for(i=inotify_fds;i<num_pollfd;i++) { |
4f45ea55 |
829 | switch(pollfd[i].revents) { |
830 | case POLLIN: |
31482529 |
831 | pthread_rwlock_rdlock(&fd_pairs_lock); |
357915bb |
832 | if(pthread_mutex_trylock(&fd_pairs->pair[i-inotify_fds].mutex) == 0) { |
5ffb77aa |
833 | /* Take care of low priority channels. */ |
083518b7 |
834 | printf_verbose( |
835 | "Normal read on fd %d\n", |
836 | pollfd[i].fd); |
5ffb77aa |
837 | /* it's ok to have an unavailable subbuffer */ |
357915bb |
838 | ret = read_subbuffer(&fd_pairs->pair[i-inotify_fds]); |
30478a4d |
839 | if(ret == EAGAIN) ret = 0; |
cdad9787 |
840 | |
357915bb |
841 | ret = pthread_mutex_unlock(&fd_pairs->pair[i-inotify_fds].mutex); |
5ffb77aa |
842 | if(ret) |
843 | printf("Error in mutex unlock : %s\n", strerror(ret)); |
844 | } |
31482529 |
845 | pthread_rwlock_unlock(&fd_pairs_lock); |
4f45ea55 |
846 | break; |
847 | } |
848 | } |
90ccaa9a |
849 | } |
850 | |
31482529 |
851 | /* Update pollfd array if an entry was added to fd_pairs */ |
852 | pthread_rwlock_rdlock(&fd_pairs_lock); |
853 | if((inotify_fds + fd_pairs->num_pairs) != num_pollfd) { |
854 | pollfd = realloc(pollfd, |
855 | (inotify_fds + fd_pairs->num_pairs) * sizeof(struct pollfd)); |
856 | for(i=num_pollfd-inotify_fds;i<fd_pairs->num_pairs;i++) { |
857 | pollfd[inotify_fds+i].fd = fd_pairs->pair[i].channel; |
858 | pollfd[inotify_fds+i].events = POLLIN|POLLPRI; |
859 | } |
860 | num_pollfd = fd_pairs->num_pairs + inotify_fds; |
861 | } |
862 | pthread_rwlock_unlock(&fd_pairs_lock); |
863 | |
864 | /* NB: If the fd_pairs structure is updated by another thread from this |
865 | * point forward, the current thread will wait in the poll without |
866 | * monitoring the new channel. However, this thread will add the |
867 | * new channel on next poll (and this should not take too much time |
868 | * on a loaded system). |
869 | * |
870 | * This event is quite unlikely and can only occur if a CPU is |
871 | * hot-plugged while multple lttd threads are running. |
872 | */ |
90ccaa9a |
873 | } |
874 | |
1d483eea |
875 | free_fd: |
90ccaa9a |
876 | free(pollfd); |
877 | |
1d483eea |
878 | end: |
357915bb |
879 | return ret; |
617de8e1 |
880 | } |
881 | |
882 | |
357915bb |
883 | void close_channel_trace_pairs(struct channel_trace_fd *fd_pairs, int inotify_fd, |
884 | struct inotify_watch_array *iwatch_array) |
617de8e1 |
885 | { |
90ccaa9a |
886 | int i; |
887 | int ret; |
617de8e1 |
888 | |
90ccaa9a |
889 | for(i=0;i<fd_pairs->num_pairs;i++) { |
890 | ret = close(fd_pairs->pair[i].channel); |
891 | if(ret == -1) perror("Close error on channel"); |
892 | ret = close(fd_pairs->pair[i].trace); |
893 | if(ret == -1) perror("Close error on trace"); |
894 | } |
895 | free(fd_pairs->pair); |
357915bb |
896 | free(iwatch_array->elem); |
897 | } |
898 | |
899 | /* Thread worker */ |
900 | void * thread_main(void *arg) |
901 | { |
31482529 |
902 | long ret; |
903 | unsigned long thread_num = (unsigned long)arg; |
904 | |
f01152ea |
905 | ret = pipe(thread_pipe); |
906 | if (ret < 0) { |
907 | perror("Error creating pipe"); |
908 | return (void*)ret; |
909 | } |
31482529 |
910 | ret = read_channels(thread_num, &fd_pairs, inotify_fd, &inotify_watch_array); |
f01152ea |
911 | close(thread_pipe[0]); /* close read end */ |
912 | close(thread_pipe[1]); /* close write end */ |
31482529 |
913 | return (void*)ret; |
914 | } |
915 | |
916 | |
917 | int channels_init() |
918 | { |
357915bb |
919 | int ret = 0; |
357915bb |
920 | |
921 | inotify_fd = inotify_init(); |
31482529 |
922 | fcntl(inotify_fd, F_SETFL, O_NONBLOCK); |
357915bb |
923 | |
924 | if(ret = open_channel_trace_pairs(channel_name, trace_name, &fd_pairs, |
925 | &inotify_fd, &inotify_watch_array)) |
926 | goto close_channel; |
c928825d |
927 | if (fd_pairs.num_pairs == 0) { |
928 | printf("No channel available for reading, exiting\n"); |
929 | ret = -ENOENT; |
930 | goto close_channel; |
931 | } |
357915bb |
932 | if(ret = map_channels(&fd_pairs, 0, fd_pairs.num_pairs)) |
933 | goto close_channel; |
31482529 |
934 | return 0; |
357915bb |
935 | |
936 | close_channel: |
937 | close_channel_trace_pairs(&fd_pairs, inotify_fd, &inotify_watch_array); |
938 | if(inotify_fd >= 0) |
939 | close(inotify_fd); |
31482529 |
940 | return ret; |
617de8e1 |
941 | } |
942 | |
31482529 |
943 | |
617de8e1 |
944 | int main(int argc, char ** argv) |
945 | { |
e54e1d5d |
946 | int ret = 0; |
1d483eea |
947 | struct sigaction act; |
5ffb77aa |
948 | pthread_t *tids; |
31482529 |
949 | unsigned long i; |
5ffb77aa |
950 | void *tret; |
617de8e1 |
951 | |
952 | ret = parse_arguments(argc, argv); |
953 | |
954 | if(ret != 0) show_arguments(); |
955 | if(ret < 0) return EINVAL; |
956 | if(ret > 0) return 0; |
957 | |
958 | show_info(); |
959 | |
1d483eea |
960 | /* Connect the signal handlers */ |
961 | act.sa_handler = handler; |
962 | act.sa_flags = 0; |
963 | sigemptyset(&(act.sa_mask)); |
964 | sigaddset(&(act.sa_mask), SIGTERM); |
965 | sigaddset(&(act.sa_mask), SIGQUIT); |
966 | sigaddset(&(act.sa_mask), SIGINT); |
967 | sigaction(SIGTERM, &act, NULL); |
968 | sigaction(SIGQUIT, &act, NULL); |
969 | sigaction(SIGINT, &act, NULL); |
970 | |
31482529 |
971 | if(ret = channels_init()) |
972 | return ret; |
973 | |
06cb3ad3 |
974 | if(daemon_mode) { |
975 | ret = daemon(0, 0); |
976 | |
977 | if(ret == -1) { |
978 | perror("An error occured while daemonizing."); |
979 | exit(-1); |
980 | } |
981 | } |
982 | |
5ffb77aa |
983 | tids = malloc(sizeof(pthread_t) * num_threads); |
984 | for(i=0; i<num_threads; i++) { |
ae410d24 |
985 | |
357915bb |
986 | ret = pthread_create(&tids[i], NULL, thread_main, (void*)i); |
5ffb77aa |
987 | if(ret) { |
988 | perror("Error creating thread"); |
989 | break; |
990 | } |
991 | } |
617de8e1 |
992 | |
5ffb77aa |
993 | for(i=0; i<num_threads; i++) { |
994 | ret = pthread_join(tids[i], &tret); |
995 | if(ret) { |
996 | perror("Error joining thread"); |
997 | break; |
998 | } |
31482529 |
999 | if((long)tret != 0) { |
1000 | printf("Error %s occured in thread %u\n", |
1001 | strerror((long)tret), i); |
5ffb77aa |
1002 | } |
1003 | } |
1004 | |
1005 | free(tids); |
31482529 |
1006 | ret = unmap_channels(&fd_pairs); |
1007 | close_channel_trace_pairs(&fd_pairs, inotify_fd, &inotify_watch_array); |
1008 | if(inotify_fd >= 0) |
1009 | close(inotify_fd); |
5ffb77aa |
1010 | |
617de8e1 |
1011 | return ret; |
1012 | } |