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) |
1b53432f |
54 | #include <sys/inotify.h> |
b3ef601b |
55 | #if 0 /* should now be provided by libc. */ |
47dbc661 |
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 | } |
b3ef601b |
71 | #endif //0 |
47dbc661 |
72 | #define HAS_INOTIFY |
73 | #else |
74 | static inline int inotify_init (void) |
75 | { |
76 | return -1; |
77 | } |
af4061b2 |
78 | |
47dbc661 |
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 |
6cecb9cf |
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; |
af4061b2 |
101 | unsigned int n_subbufs; |
102 | unsigned int subbuf_size; |
103 | void *mmap; |
22acb617 |
104 | pthread_mutex_t mutex; |
6cecb9cf |
105 | }; |
106 | |
107 | struct channel_trace_fd { |
108 | struct fd_pair *pair; |
109 | int num_pairs; |
110 | }; |
111 | |
47dbc661 |
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 | |
d61d094a |
123 | static __thread int thread_pipe[2]; |
d66cc831 |
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 | |
d24c12e7 |
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; |
af4061b2 |
138 | volatile static int quit_program = 0; /* For signal handler */ |
d24c12e7 |
139 | static int dump_flight_only = 0; |
140 | static int dump_normal_only = 0; |
51f9cfd2 |
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) |
6cecb9cf |
148 | |
149 | /* Args : |
150 | * |
151 | * -t directory Directory name of the trace to write to. Will be created. |
bb01fdc6 |
152 | * -c directory Root directory of the debugfs trace channels. |
6cecb9cf |
153 | * -d Run in background (daemon). |
51f9cfd2 |
154 | * -a Trace append mode. |
155 | * -s Send SIGUSR1 to parent when ready for IO. |
6cecb9cf |
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"); |
bb01fdc6 |
163 | printf("-c directory Root directory of the debugfs trace channels.\n"); |
6cecb9cf |
164 | printf("-d Run in background (daemon).\n"); |
9e7dbe44 |
165 | printf("-a Append to an possibly existing trace.\n"); |
22acb617 |
166 | printf("-N Number of threads to start.\n"); |
d24c12e7 |
167 | printf("-f Dump only flight recorder channels.\n"); |
168 | printf("-n Dump only normal channels.\n"); |
51f9cfd2 |
169 | printf("-v Verbose mode.\n"); |
6cecb9cf |
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 | |
9e7dbe44 |
192 | while(argn < argc) { |
6cecb9cf |
193 | |
194 | switch(argv[argn][0]) { |
195 | case '-': |
196 | switch(argv[argn][1]) { |
197 | case 't': |
9e7dbe44 |
198 | if(argn+1 < argc) { |
199 | trace_name = argv[argn+1]; |
200 | argn++; |
201 | } |
6cecb9cf |
202 | break; |
203 | case 'c': |
9e7dbe44 |
204 | if(argn+1 < argc) { |
205 | channel_name = argv[argn+1]; |
206 | argn++; |
207 | } |
6cecb9cf |
208 | break; |
209 | case 'd': |
210 | daemon_mode = 1; |
211 | break; |
9e7dbe44 |
212 | case 'a': |
213 | append_mode = 1; |
214 | break; |
22acb617 |
215 | case 'N': |
c3e8c24f |
216 | if(argn+1 < argc) { |
217 | num_threads = strtoul(argv[argn+1], NULL, 0); |
218 | argn++; |
219 | } |
220 | break; |
d24c12e7 |
221 | case 'f': |
222 | dump_flight_only = 1; |
223 | break; |
224 | case 'n': |
225 | dump_normal_only = 1; |
226 | break; |
51f9cfd2 |
227 | case 'v': |
228 | verbose_mode = 1; |
229 | break; |
6cecb9cf |
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 | { |
e7480f75 |
261 | printf("Linux Trace Toolkit Trace Daemon " VERSION "\n"); |
6cecb9cf |
262 | printf("\n"); |
bb01fdc6 |
263 | printf("Reading from debugfs directory : %s\n", channel_name); |
6cecb9cf |
264 | printf("Writing to trace directory : %s\n", trace_name); |
265 | printf("\n"); |
266 | } |
267 | |
268 | |
af4061b2 |
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 | |
47dbc661 |
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) { |
51f9cfd2 |
287 | printf_verbose("Skipping normal channel %s\n", |
288 | path_channel); |
47dbc661 |
289 | return 0; |
290 | } |
291 | } else { |
292 | if(dump_normal_only) { |
51f9cfd2 |
293 | printf_verbose("Skipping flight channel %s\n", |
294 | path_channel); |
47dbc661 |
295 | return 0; |
296 | } |
297 | } |
51f9cfd2 |
298 | printf_verbose("Opening file.\n"); |
47dbc661 |
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) { |
51f9cfd2 |
315 | printf_verbose("Appending to file %s as requested\n", |
316 | path_trace); |
47dbc661 |
317 | |
318 | fd_pairs->pair[fd_pairs->num_pairs-1].trace = |
319 | open(path_trace, O_WRONLY|O_APPEND, |
320 | S_IRWXU|S_IRWXG|S_IRWXO); |
321 | |
322 | if(fd_pairs->pair[fd_pairs->num_pairs-1].trace == -1) { |
323 | perror(path_trace); |
324 | } |
325 | } else { |
326 | printf("File %s exists, cannot open. Try append mode.\n", path_trace); |
327 | open_ret = -1; |
328 | goto end; |
329 | } |
330 | } else { |
331 | if(errno == ENOENT) { |
332 | fd_pairs->pair[fd_pairs->num_pairs-1].trace = |
333 | open(path_trace, O_WRONLY|O_CREAT|O_EXCL, |
334 | S_IRWXU|S_IRWXG|S_IRWXO); |
335 | if(fd_pairs->pair[fd_pairs->num_pairs-1].trace == -1) { |
336 | perror(path_trace); |
337 | } |
338 | } |
339 | } |
340 | end: |
341 | return open_ret; |
342 | } |
af4061b2 |
343 | |
6cecb9cf |
344 | int open_channel_trace_pairs(char *subchannel_name, char *subtrace_name, |
47dbc661 |
345 | struct channel_trace_fd *fd_pairs, int *inotify_fd, |
346 | struct inotify_watch_array *iwatch_array) |
6cecb9cf |
347 | { |
348 | DIR *channel_dir = opendir(subchannel_name); |
349 | struct dirent *entry; |
350 | struct stat stat_buf; |
351 | int ret; |
352 | char path_channel[PATH_MAX]; |
353 | int path_channel_len; |
354 | char *path_channel_ptr; |
355 | char path_trace[PATH_MAX]; |
356 | int path_trace_len; |
357 | char *path_trace_ptr; |
4d508021 |
358 | int open_ret = 0; |
6cecb9cf |
359 | |
360 | if(channel_dir == NULL) { |
361 | perror(subchannel_name); |
02ba971e |
362 | open_ret = ENOENT; |
4d508021 |
363 | goto end; |
6cecb9cf |
364 | } |
365 | |
51f9cfd2 |
366 | printf_verbose("Creating trace subdirectory %s\n", subtrace_name); |
6cecb9cf |
367 | ret = mkdir(subtrace_name, S_IRWXU|S_IRWXG|S_IRWXO); |
368 | if(ret == -1) { |
3986d00b |
369 | if(errno != EEXIST) { |
9e7dbe44 |
370 | perror(subtrace_name); |
4d508021 |
371 | open_ret = -1; |
02ba971e |
372 | goto end; |
9e7dbe44 |
373 | } |
6cecb9cf |
374 | } |
375 | |
376 | strncpy(path_channel, subchannel_name, PATH_MAX-1); |
377 | path_channel_len = strlen(path_channel); |
378 | path_channel[path_channel_len] = '/'; |
379 | path_channel_len++; |
380 | path_channel_ptr = path_channel + path_channel_len; |
381 | |
382 | strncpy(path_trace, subtrace_name, PATH_MAX-1); |
383 | path_trace_len = strlen(path_trace); |
384 | path_trace[path_trace_len] = '/'; |
385 | path_trace_len++; |
386 | path_trace_ptr = path_trace + path_trace_len; |
387 | |
47dbc661 |
388 | #ifdef HAS_INOTIFY |
389 | iwatch_array->elem = realloc(iwatch_array->elem, |
390 | ++iwatch_array->num * sizeof(struct inotify_watch)); |
391 | |
51f9cfd2 |
392 | printf_verbose("Adding inotify for channel %s\n", path_channel); |
47dbc661 |
393 | iwatch_array->elem[iwatch_array->num-1].wd = inotify_add_watch(*inotify_fd, path_channel, IN_CREATE); |
394 | strcpy(iwatch_array->elem[iwatch_array->num-1].path_channel, path_channel); |
395 | strcpy(iwatch_array->elem[iwatch_array->num-1].path_trace, path_trace); |
51f9cfd2 |
396 | printf_verbose("Added inotify for channel %s, wd %u\n", |
397 | iwatch_array->elem[iwatch_array->num-1].path_channel, |
47dbc661 |
398 | iwatch_array->elem[iwatch_array->num-1].wd); |
399 | #endif |
400 | |
6cecb9cf |
401 | while((entry = readdir(channel_dir)) != NULL) { |
402 | |
403 | if(entry->d_name[0] == '.') continue; |
404 | |
405 | strncpy(path_channel_ptr, entry->d_name, PATH_MAX - path_channel_len); |
406 | strncpy(path_trace_ptr, entry->d_name, PATH_MAX - path_trace_len); |
407 | |
408 | ret = stat(path_channel, &stat_buf); |
409 | if(ret == -1) { |
410 | perror(path_channel); |
411 | continue; |
412 | } |
413 | |
51f9cfd2 |
414 | printf_verbose("Channel file : %s\n", path_channel); |
6cecb9cf |
415 | |
416 | if(S_ISDIR(stat_buf.st_mode)) { |
417 | |
51f9cfd2 |
418 | printf_verbose("Entering channel subdirectory...\n"); |
47dbc661 |
419 | ret = open_channel_trace_pairs(path_channel, path_trace, fd_pairs, |
420 | inotify_fd, iwatch_array); |
6cecb9cf |
421 | if(ret < 0) continue; |
9e7dbe44 |
422 | } else if(S_ISREG(stat_buf.st_mode)) { |
47dbc661 |
423 | open_ret = open_buffer_file(entry->d_name, path_channel, path_trace, |
424 | fd_pairs); |
425 | if(open_ret) |
426 | goto end; |
6cecb9cf |
427 | } |
6cecb9cf |
428 | } |
429 | |
02ba971e |
430 | end: |
6cecb9cf |
431 | closedir(channel_dir); |
432 | |
02ba971e |
433 | return open_ret; |
6cecb9cf |
434 | } |
435 | |
af4061b2 |
436 | |
437 | int read_subbuffer(struct fd_pair *pair) |
438 | { |
d61d094a |
439 | unsigned int consumed_old; |
440 | int err; |
441 | long ret; |
6ef15f13 |
442 | unsigned long len; |
443 | off_t offset; |
af4061b2 |
444 | |
445 | |
d61d094a |
446 | err = ioctl(pair->channel, RELAY_GET_SUBBUF, &consumed_old); |
51f9cfd2 |
447 | printf_verbose("cookie : %u\n", consumed_old); |
13474e75 |
448 | if(err != 0) { |
22acb617 |
449 | ret = errno; |
63bf9ed1 |
450 | perror("Reserving sub buffer failed (everything is normal, it is due to concurrency)"); |
13474e75 |
451 | goto get_error; |
af4061b2 |
452 | } |
d61d094a |
453 | #if 0 |
13474e75 |
454 | err = TEMP_FAILURE_RETRY(write(pair->trace, |
2312de30 |
455 | pair->mmap |
456 | + (consumed_old & ((pair->n_subbufs * pair->subbuf_size)-1)), |
af4061b2 |
457 | pair->subbuf_size)); |
13474e75 |
458 | |
459 | if(err < 0) { |
22acb617 |
460 | ret = errno; |
af4061b2 |
461 | perror("Error in writing to file"); |
13474e75 |
462 | goto write_error; |
af4061b2 |
463 | } |
d61d094a |
464 | #endif //0 |
465 | len = pair->subbuf_size; |
466 | offset = 0; |
467 | while (len > 0) { |
6ef15f13 |
468 | printf_verbose("splice chan to pipe offset %lu\n", |
469 | (unsigned long)offset); |
d61d094a |
470 | ret = splice(pair->channel, &offset, thread_pipe[1], NULL, |
471 | len, SPLICE_F_MOVE); |
51f9cfd2 |
472 | printf_verbose("splice chan to pipe ret %ld\n", ret); |
d61d094a |
473 | if (ret < 0) { |
474 | perror("Error in relay splice"); |
475 | goto write_error; |
476 | } |
477 | ret = splice(thread_pipe[0], NULL, pair->trace, NULL, |
478 | ret, SPLICE_F_MOVE); |
51f9cfd2 |
479 | printf_verbose("splice pipe to file %ld\n", ret); |
d61d094a |
480 | if (ret < 0) { |
481 | perror("Error in file splice"); |
482 | goto write_error; |
483 | } |
484 | len -= ret; |
485 | } |
486 | |
c5fdfca5 |
487 | #if 0 |
488 | err = fsync(pair->trace); |
489 | if(err < 0) { |
490 | ret = errno; |
491 | perror("Error in writing to file"); |
492 | goto write_error; |
493 | } |
494 | #endif //0 |
13474e75 |
495 | write_error: |
d61d094a |
496 | ret = 0; |
bb01fdc6 |
497 | err = ioctl(pair->channel, RELAY_PUT_SUBBUF, &consumed_old); |
13474e75 |
498 | if(err != 0) { |
22acb617 |
499 | ret = errno; |
63bf9ed1 |
500 | if(errno == EFAULT) { |
22acb617 |
501 | perror("Error in unreserving sub buffer\n"); |
63bf9ed1 |
502 | } else if(errno == EIO) { |
12bcec97 |
503 | perror("Reader has been pushed by the writer, last subbuffer corrupted."); |
db9d75c0 |
504 | /* FIXME : we may delete the last written buffer if we wish. */ |
12bcec97 |
505 | } |
13474e75 |
506 | goto get_error; |
af4061b2 |
507 | } |
508 | |
13474e75 |
509 | get_error: |
510 | return ret; |
af4061b2 |
511 | } |
512 | |
513 | |
47dbc661 |
514 | int map_channels(struct channel_trace_fd *fd_pairs, |
515 | int idx_begin, int idx_end) |
6cecb9cf |
516 | { |
af4061b2 |
517 | int i,j; |
c3e8c24f |
518 | int ret=0; |
af4061b2 |
519 | |
13474e75 |
520 | if(fd_pairs->num_pairs <= 0) { |
521 | printf("No channel to read\n"); |
522 | goto end; |
523 | } |
524 | |
af4061b2 |
525 | /* Get the subbuf sizes and number */ |
526 | |
47dbc661 |
527 | for(i=idx_begin;i<idx_end;i++) { |
af4061b2 |
528 | struct fd_pair *pair = &fd_pairs->pair[i]; |
9e7dbe44 |
529 | |
bb01fdc6 |
530 | ret = ioctl(pair->channel, RELAY_GET_N_SUBBUFS, |
af4061b2 |
531 | &pair->n_subbufs); |
532 | if(ret != 0) { |
533 | perror("Error in getting the number of subbuffers"); |
534 | goto end; |
535 | } |
bb01fdc6 |
536 | ret = ioctl(pair->channel, RELAY_GET_SUBBUF_SIZE, |
af4061b2 |
537 | &pair->subbuf_size); |
538 | if(ret != 0) { |
539 | perror("Error in getting the size of the subbuffers"); |
540 | goto end; |
541 | } |
22acb617 |
542 | ret = pthread_mutex_init(&pair->mutex, NULL); /* Fast mutex */ |
543 | if(ret != 0) { |
544 | perror("Error in mutex init"); |
545 | goto end; |
546 | } |
af4061b2 |
547 | } |
548 | |
d61d094a |
549 | #if 0 |
af4061b2 |
550 | /* Mmap each FD */ |
47dbc661 |
551 | for(i=idx_begin;i<idx_end;i++) { |
af4061b2 |
552 | struct fd_pair *pair = &fd_pairs->pair[i]; |
553 | |
554 | pair->mmap = mmap(0, pair->subbuf_size * pair->n_subbufs, PROT_READ, |
555 | MAP_SHARED, pair->channel, 0); |
556 | if(pair->mmap == MAP_FAILED) { |
557 | perror("Mmap error"); |
558 | goto munmap; |
559 | } |
560 | } |
561 | |
22acb617 |
562 | goto end; /* success */ |
af4061b2 |
563 | |
c3e8c24f |
564 | /* Error handling */ |
565 | /* munmap only the successfully mmapped indexes */ |
566 | munmap: |
567 | /* Munmap each FD */ |
47dbc661 |
568 | for(j=idx_begin;j<i;j++) { |
c3e8c24f |
569 | struct fd_pair *pair = &fd_pairs->pair[j]; |
570 | int err_ret; |
571 | |
572 | err_ret = munmap(pair->mmap, pair->subbuf_size * pair->n_subbufs); |
573 | if(err_ret != 0) { |
574 | perror("Error in munmap"); |
575 | } |
576 | ret |= err_ret; |
577 | } |
578 | |
d61d094a |
579 | #endif //0 |
c3e8c24f |
580 | end: |
581 | return ret; |
c3e8c24f |
582 | } |
583 | |
c3e8c24f |
584 | int unmap_channels(struct channel_trace_fd *fd_pairs) |
585 | { |
586 | int j; |
587 | int ret=0; |
588 | |
589 | /* Munmap each FD */ |
590 | for(j=0;j<fd_pairs->num_pairs;j++) { |
591 | struct fd_pair *pair = &fd_pairs->pair[j]; |
592 | int err_ret; |
593 | |
d61d094a |
594 | #if 0 |
c3e8c24f |
595 | err_ret = munmap(pair->mmap, pair->subbuf_size * pair->n_subbufs); |
596 | if(err_ret != 0) { |
597 | perror("Error in munmap"); |
598 | } |
599 | ret |= err_ret; |
d61d094a |
600 | #endif //0 |
22acb617 |
601 | err_ret = pthread_mutex_destroy(&pair->mutex); |
602 | if(err_ret != 0) { |
603 | perror("Error in mutex destroy"); |
604 | } |
605 | ret |= err_ret; |
c3e8c24f |
606 | } |
607 | |
608 | return ret; |
609 | } |
610 | |
47dbc661 |
611 | #ifdef HAS_INOTIFY |
612 | /* Inotify event arrived. |
613 | * |
614 | * Only support add file for now. |
615 | */ |
616 | |
617 | int read_inotify(int inotify_fd, |
618 | struct channel_trace_fd *fd_pairs, |
619 | struct inotify_watch_array *iwatch_array) |
620 | { |
621 | char buf[sizeof(struct inotify_event) + PATH_MAX]; |
622 | char path_channel[PATH_MAX]; |
623 | char path_trace[PATH_MAX]; |
624 | ssize_t len; |
625 | struct inotify_event *ievent; |
626 | size_t offset; |
627 | unsigned int i; |
628 | int ret; |
629 | int old_num; |
630 | |
631 | offset = 0; |
632 | len = read(inotify_fd, buf, sizeof(struct inotify_event) + PATH_MAX); |
633 | if(len < 0) { |
d66cc831 |
634 | |
635 | if(errno == EAGAIN) |
636 | return 0; /* another thread got the data before us */ |
637 | |
47dbc661 |
638 | printf("Error in read from inotify FD %s.\n", strerror(len)); |
639 | return -1; |
640 | } |
641 | while(offset < len) { |
642 | ievent = (struct inotify_event *)&(buf[offset]); |
643 | for(i=0; i<iwatch_array->num; i++) { |
644 | if(iwatch_array->elem[i].wd == ievent->wd && |
645 | ievent->mask == IN_CREATE) { |
51f9cfd2 |
646 | printf_verbose( |
647 | "inotify wd %u event mask : %u for %s%s\n", |
47dbc661 |
648 | ievent->wd, ievent->mask, |
51f9cfd2 |
649 | iwatch_array->elem[i].path_channel, |
650 | ievent->name); |
47dbc661 |
651 | old_num = fd_pairs->num_pairs; |
652 | strcpy(path_channel, iwatch_array->elem[i].path_channel); |
653 | strcat(path_channel, ievent->name); |
654 | strcpy(path_trace, iwatch_array->elem[i].path_trace); |
655 | strcat(path_trace, ievent->name); |
656 | if(ret = open_buffer_file(ievent->name, path_channel, |
657 | path_trace, fd_pairs)) { |
658 | printf("Error opening buffer file\n"); |
659 | return -1; |
660 | } |
661 | if(ret = map_channels(fd_pairs, old_num, fd_pairs->num_pairs)) { |
662 | printf("Error mapping channel\n"); |
663 | return -1; |
664 | } |
665 | |
666 | } |
667 | } |
668 | offset += sizeof(*ievent) + ievent->len; |
669 | } |
670 | } |
671 | #endif //HAS_INOTIFY |
c3e8c24f |
672 | |
673 | /* read_channels |
22acb617 |
674 | * |
675 | * Thread worker. |
c3e8c24f |
676 | * |
bb01fdc6 |
677 | * Read the debugfs channels and write them in the paired tracefiles. |
c3e8c24f |
678 | * |
679 | * @fd_pairs : paired channels and trace files. |
680 | * |
47dbc661 |
681 | * returns 0 on success, -1 on error. |
c3e8c24f |
682 | * |
683 | * Note that the high priority polled channels are consumed first. We then poll |
684 | * again to see if these channels are still in priority. Only when no |
685 | * high priority channel is left, we start reading low priority channels. |
686 | * |
687 | * Note that a channel is considered high priority when the buffer is almost |
688 | * full. |
689 | */ |
690 | |
d66cc831 |
691 | int read_channels(unsigned long thread_num, struct channel_trace_fd *fd_pairs, |
47dbc661 |
692 | int inotify_fd, struct inotify_watch_array *iwatch_array) |
c3e8c24f |
693 | { |
47dbc661 |
694 | struct pollfd *pollfd = NULL; |
d66cc831 |
695 | int num_pollfd; |
c3e8c24f |
696 | int i,j; |
697 | int num_rdy, num_hup; |
698 | int high_prio; |
22acb617 |
699 | int ret = 0; |
47dbc661 |
700 | int inotify_fds; |
701 | unsigned int old_num; |
c3e8c24f |
702 | |
47dbc661 |
703 | #ifdef HAS_INOTIFY |
704 | inotify_fds = 1; |
705 | #else |
706 | inotify_fds = 0; |
707 | #endif |
708 | |
d66cc831 |
709 | pthread_rwlock_rdlock(&fd_pairs_lock); |
710 | |
47dbc661 |
711 | /* Start polling the FD. Keep one fd for inotify */ |
712 | pollfd = malloc((inotify_fds + fd_pairs->num_pairs) * sizeof(struct pollfd)); |
713 | |
714 | #ifdef HAS_INOTIFY |
715 | pollfd[0].fd = inotify_fd; |
716 | pollfd[0].events = POLLIN|POLLPRI; |
717 | #endif |
9e7dbe44 |
718 | |
719 | for(i=0;i<fd_pairs->num_pairs;i++) { |
47dbc661 |
720 | pollfd[inotify_fds+i].fd = fd_pairs->pair[i].channel; |
721 | pollfd[inotify_fds+i].events = POLLIN|POLLPRI; |
9e7dbe44 |
722 | } |
d66cc831 |
723 | num_pollfd = inotify_fds + fd_pairs->num_pairs; |
724 | |
725 | |
726 | pthread_rwlock_unlock(&fd_pairs_lock); |
727 | |
9e7dbe44 |
728 | while(1) { |
68047576 |
729 | high_prio = 0; |
af4061b2 |
730 | num_hup = 0; |
731 | #ifdef DEBUG |
732 | printf("Press a key for next poll...\n"); |
733 | char buf[1]; |
734 | read(STDIN_FILENO, &buf, 1); |
d66cc831 |
735 | printf("Next poll (polling %d fd) :\n", num_pollfd); |
af4061b2 |
736 | #endif //DEBUG |
47dbc661 |
737 | |
af4061b2 |
738 | /* Have we received a signal ? */ |
739 | if(quit_program) break; |
740 | |
d66cc831 |
741 | num_rdy = poll(pollfd, num_pollfd, -1); |
742 | |
9e7dbe44 |
743 | if(num_rdy == -1) { |
744 | perror("Poll error"); |
af4061b2 |
745 | goto free_fd; |
9e7dbe44 |
746 | } |
747 | |
51f9cfd2 |
748 | printf_verbose("Data received\n"); |
47dbc661 |
749 | #ifdef HAS_INOTIFY |
750 | switch(pollfd[0].revents) { |
751 | case POLLERR: |
51f9cfd2 |
752 | printf_verbose( |
753 | "Error returned in polling inotify fd %d.\n", |
754 | pollfd[0].fd); |
47dbc661 |
755 | break; |
756 | case POLLHUP: |
51f9cfd2 |
757 | printf_verbose( |
758 | "Polling inotify fd %d tells it has hung up.\n", |
759 | pollfd[0].fd); |
47dbc661 |
760 | break; |
761 | case POLLNVAL: |
51f9cfd2 |
762 | printf_verbose( |
763 | "Polling inotify fd %d tells fd is not open.\n", |
764 | pollfd[0].fd); |
47dbc661 |
765 | break; |
766 | case POLLPRI: |
767 | case POLLIN: |
51f9cfd2 |
768 | printf_verbose( |
769 | "Polling inotify fd %d : data ready.\n", |
770 | pollfd[0].fd); |
d66cc831 |
771 | |
772 | pthread_rwlock_wrlock(&fd_pairs_lock); |
47dbc661 |
773 | read_inotify(inotify_fd, fd_pairs, iwatch_array); |
d66cc831 |
774 | pthread_rwlock_unlock(&fd_pairs_lock); |
775 | |
47dbc661 |
776 | break; |
777 | } |
778 | #endif |
9e7dbe44 |
779 | |
d66cc831 |
780 | for(i=inotify_fds;i<num_pollfd;i++) { |
9e7dbe44 |
781 | switch(pollfd[i].revents) { |
782 | case POLLERR: |
51f9cfd2 |
783 | printf_verbose( |
784 | "Error returned in polling fd %d.\n", |
785 | pollfd[i].fd); |
af4061b2 |
786 | num_hup++; |
9e7dbe44 |
787 | break; |
788 | case POLLHUP: |
51f9cfd2 |
789 | printf_verbose( |
790 | "Polling fd %d tells it has hung up.\n", |
791 | pollfd[i].fd); |
af4061b2 |
792 | num_hup++; |
9e7dbe44 |
793 | break; |
794 | case POLLNVAL: |
51f9cfd2 |
795 | printf_verbose( |
796 | "Polling fd %d tells fd is not open.\n", |
797 | pollfd[i].fd); |
af4061b2 |
798 | num_hup++; |
9e7dbe44 |
799 | break; |
800 | case POLLPRI: |
d66cc831 |
801 | pthread_rwlock_rdlock(&fd_pairs_lock); |
47dbc661 |
802 | if(pthread_mutex_trylock(&fd_pairs->pair[i-inotify_fds].mutex) == 0) { |
51f9cfd2 |
803 | printf_verbose( |
804 | "Urgent read on fd %d\n", |
805 | pollfd[i].fd); |
22acb617 |
806 | /* Take care of high priority channels first. */ |
807 | high_prio = 1; |
808 | /* it's ok to have an unavailable subbuffer */ |
47dbc661 |
809 | ret = read_subbuffer(&fd_pairs->pair[i-inotify_fds]); |
63bf9ed1 |
810 | if(ret == EAGAIN) ret = 0; |
b8d28629 |
811 | |
47dbc661 |
812 | ret = pthread_mutex_unlock(&fd_pairs->pair[i-inotify_fds].mutex); |
22acb617 |
813 | if(ret) |
814 | printf("Error in mutex unlock : %s\n", strerror(ret)); |
815 | } |
d66cc831 |
816 | pthread_rwlock_unlock(&fd_pairs_lock); |
9e7dbe44 |
817 | break; |
68047576 |
818 | } |
9e7dbe44 |
819 | } |
47dbc661 |
820 | /* If every buffer FD has hung up, we end the read loop here */ |
d66cc831 |
821 | if(num_hup == num_pollfd - inotify_fds) break; |
9e7dbe44 |
822 | |
68047576 |
823 | if(!high_prio) { |
d66cc831 |
824 | for(i=inotify_fds;i<num_pollfd;i++) { |
68047576 |
825 | switch(pollfd[i].revents) { |
826 | case POLLIN: |
d66cc831 |
827 | pthread_rwlock_rdlock(&fd_pairs_lock); |
47dbc661 |
828 | if(pthread_mutex_trylock(&fd_pairs->pair[i-inotify_fds].mutex) == 0) { |
22acb617 |
829 | /* Take care of low priority channels. */ |
51f9cfd2 |
830 | printf_verbose( |
831 | "Normal read on fd %d\n", |
832 | pollfd[i].fd); |
22acb617 |
833 | /* it's ok to have an unavailable subbuffer */ |
47dbc661 |
834 | ret = read_subbuffer(&fd_pairs->pair[i-inotify_fds]); |
63bf9ed1 |
835 | if(ret == EAGAIN) ret = 0; |
b8d28629 |
836 | |
47dbc661 |
837 | ret = pthread_mutex_unlock(&fd_pairs->pair[i-inotify_fds].mutex); |
22acb617 |
838 | if(ret) |
839 | printf("Error in mutex unlock : %s\n", strerror(ret)); |
840 | } |
d66cc831 |
841 | pthread_rwlock_unlock(&fd_pairs_lock); |
68047576 |
842 | break; |
843 | } |
844 | } |
9e7dbe44 |
845 | } |
846 | |
d66cc831 |
847 | /* Update pollfd array if an entry was added to fd_pairs */ |
848 | pthread_rwlock_rdlock(&fd_pairs_lock); |
849 | if((inotify_fds + fd_pairs->num_pairs) != num_pollfd) { |
850 | pollfd = realloc(pollfd, |
851 | (inotify_fds + fd_pairs->num_pairs) * sizeof(struct pollfd)); |
852 | for(i=num_pollfd-inotify_fds;i<fd_pairs->num_pairs;i++) { |
853 | pollfd[inotify_fds+i].fd = fd_pairs->pair[i].channel; |
854 | pollfd[inotify_fds+i].events = POLLIN|POLLPRI; |
855 | } |
856 | num_pollfd = fd_pairs->num_pairs + inotify_fds; |
857 | } |
858 | pthread_rwlock_unlock(&fd_pairs_lock); |
859 | |
860 | /* NB: If the fd_pairs structure is updated by another thread from this |
861 | * point forward, the current thread will wait in the poll without |
862 | * monitoring the new channel. However, this thread will add the |
863 | * new channel on next poll (and this should not take too much time |
864 | * on a loaded system). |
865 | * |
866 | * This event is quite unlikely and can only occur if a CPU is |
867 | * hot-plugged while multple lttd threads are running. |
868 | */ |
9e7dbe44 |
869 | } |
870 | |
af4061b2 |
871 | free_fd: |
9e7dbe44 |
872 | free(pollfd); |
873 | |
af4061b2 |
874 | end: |
47dbc661 |
875 | return ret; |
6cecb9cf |
876 | } |
877 | |
878 | |
47dbc661 |
879 | void close_channel_trace_pairs(struct channel_trace_fd *fd_pairs, int inotify_fd, |
880 | struct inotify_watch_array *iwatch_array) |
6cecb9cf |
881 | { |
9e7dbe44 |
882 | int i; |
883 | int ret; |
6cecb9cf |
884 | |
9e7dbe44 |
885 | for(i=0;i<fd_pairs->num_pairs;i++) { |
886 | ret = close(fd_pairs->pair[i].channel); |
887 | if(ret == -1) perror("Close error on channel"); |
888 | ret = close(fd_pairs->pair[i].trace); |
889 | if(ret == -1) perror("Close error on trace"); |
890 | } |
891 | free(fd_pairs->pair); |
47dbc661 |
892 | free(iwatch_array->elem); |
893 | } |
894 | |
895 | /* Thread worker */ |
896 | void * thread_main(void *arg) |
897 | { |
d66cc831 |
898 | long ret; |
899 | unsigned long thread_num = (unsigned long)arg; |
900 | |
d61d094a |
901 | ret = pipe(thread_pipe); |
902 | if (ret < 0) { |
903 | perror("Error creating pipe"); |
904 | return (void*)ret; |
905 | } |
d66cc831 |
906 | ret = read_channels(thread_num, &fd_pairs, inotify_fd, &inotify_watch_array); |
d61d094a |
907 | close(thread_pipe[0]); /* close read end */ |
908 | close(thread_pipe[1]); /* close write end */ |
d66cc831 |
909 | return (void*)ret; |
910 | } |
911 | |
912 | |
913 | int channels_init() |
914 | { |
47dbc661 |
915 | int ret = 0; |
47dbc661 |
916 | |
917 | inotify_fd = inotify_init(); |
d66cc831 |
918 | fcntl(inotify_fd, F_SETFL, O_NONBLOCK); |
47dbc661 |
919 | |
920 | if(ret = open_channel_trace_pairs(channel_name, trace_name, &fd_pairs, |
921 | &inotify_fd, &inotify_watch_array)) |
922 | goto close_channel; |
64ba9405 |
923 | if (fd_pairs.num_pairs == 0) { |
924 | printf("No channel available for reading, exiting\n"); |
925 | ret = -ENOENT; |
926 | goto close_channel; |
927 | } |
47dbc661 |
928 | if(ret = map_channels(&fd_pairs, 0, fd_pairs.num_pairs)) |
929 | goto close_channel; |
d66cc831 |
930 | return 0; |
47dbc661 |
931 | |
932 | close_channel: |
933 | close_channel_trace_pairs(&fd_pairs, inotify_fd, &inotify_watch_array); |
934 | if(inotify_fd >= 0) |
935 | close(inotify_fd); |
d66cc831 |
936 | return ret; |
6cecb9cf |
937 | } |
938 | |
d66cc831 |
939 | |
6cecb9cf |
940 | int main(int argc, char ** argv) |
941 | { |
c3e8c24f |
942 | int ret = 0; |
af4061b2 |
943 | struct sigaction act; |
22acb617 |
944 | pthread_t *tids; |
d66cc831 |
945 | unsigned long i; |
22acb617 |
946 | void *tret; |
6cecb9cf |
947 | |
948 | ret = parse_arguments(argc, argv); |
949 | |
950 | if(ret != 0) show_arguments(); |
951 | if(ret < 0) return EINVAL; |
952 | if(ret > 0) return 0; |
953 | |
954 | show_info(); |
955 | |
af4061b2 |
956 | /* Connect the signal handlers */ |
957 | act.sa_handler = handler; |
958 | act.sa_flags = 0; |
959 | sigemptyset(&(act.sa_mask)); |
960 | sigaddset(&(act.sa_mask), SIGTERM); |
961 | sigaddset(&(act.sa_mask), SIGQUIT); |
962 | sigaddset(&(act.sa_mask), SIGINT); |
963 | sigaction(SIGTERM, &act, NULL); |
964 | sigaction(SIGQUIT, &act, NULL); |
965 | sigaction(SIGINT, &act, NULL); |
966 | |
d66cc831 |
967 | if(ret = channels_init()) |
968 | return ret; |
969 | |
ebb39a89 |
970 | if(daemon_mode) { |
971 | ret = daemon(0, 0); |
972 | |
973 | if(ret == -1) { |
974 | perror("An error occured while daemonizing."); |
975 | exit(-1); |
976 | } |
977 | } |
978 | |
22acb617 |
979 | tids = malloc(sizeof(pthread_t) * num_threads); |
980 | for(i=0; i<num_threads; i++) { |
d3b6d84f |
981 | |
47dbc661 |
982 | ret = pthread_create(&tids[i], NULL, thread_main, (void*)i); |
22acb617 |
983 | if(ret) { |
984 | perror("Error creating thread"); |
985 | break; |
986 | } |
987 | } |
6cecb9cf |
988 | |
22acb617 |
989 | for(i=0; i<num_threads; i++) { |
990 | ret = pthread_join(tids[i], &tret); |
991 | if(ret) { |
992 | perror("Error joining thread"); |
993 | break; |
994 | } |
d66cc831 |
995 | if((long)tret != 0) { |
996 | printf("Error %s occured in thread %u\n", |
997 | strerror((long)tret), i); |
22acb617 |
998 | } |
999 | } |
1000 | |
1001 | free(tids); |
d66cc831 |
1002 | ret = unmap_channels(&fd_pairs); |
1003 | close_channel_trace_pairs(&fd_pairs, inotify_fd, &inotify_watch_array); |
1004 | if(inotify_fd >= 0) |
1005 | close(inotify_fd); |
22acb617 |
1006 | |
6cecb9cf |
1007 | return ret; |
1008 | } |