Commit | Line | Data |
---|---|---|
1d498196 | 1 | /* |
c0c0989a | 2 | * SPDX-License-Identifier: LGPL-2.1-only |
1d498196 | 3 | * |
e92f3e28 | 4 | * Copyright (C) 2005-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
1d498196 MD |
5 | */ |
6 | ||
3fbec7dc | 7 | #define _LGPL_SOURCE |
1d498196 MD |
8 | #include "shm.h" |
9 | #include <unistd.h> | |
10 | #include <fcntl.h> | |
11 | #include <sys/mman.h> | |
a9ff648c | 12 | #include <sys/types.h> |
1d498196 MD |
13 | #include <sys/stat.h> /* For mode constants */ |
14 | #include <fcntl.h> /* For O_* constants */ | |
15 | #include <assert.h> | |
8da6cd6d MD |
16 | #include <stdio.h> |
17 | #include <signal.h> | |
18 | #include <dirent.h> | |
96e80018 | 19 | #include <limits.h> |
8a208943 | 20 | #include <stdbool.h> |
fb31eb73 | 21 | #include <stdint.h> |
3d3a2bb8 | 22 | |
bfcda6ce | 23 | #ifdef HAVE_LIBNUMA |
4b68c31f | 24 | #include <numa.h> |
8a208943 | 25 | #include <numaif.h> |
bfcda6ce | 26 | #endif |
3d3a2bb8 | 27 | |
eae3c729 | 28 | #include <lttng/ust-utils.h> |
3d3a2bb8 | 29 | |
9d315d6d MJ |
30 | #include "common/macros.h" |
31 | #include "common/ust-fd.h" | |
1be43539 | 32 | #include "common/compat/mmap.h" |
3a81f31d MD |
33 | |
34 | /* | |
35 | * Ensure we have the required amount of space available by writing 0 | |
36 | * into the entire buffer. Not doing so can trigger SIGBUS when going | |
37 | * beyond the available shm space. | |
38 | */ | |
39 | static | |
40 | int zero_file(int fd, size_t len) | |
41 | { | |
42 | ssize_t retlen; | |
43 | size_t written = 0; | |
44 | char *zeropage; | |
45 | long pagelen; | |
46 | int ret; | |
47 | ||
48 | pagelen = sysconf(_SC_PAGESIZE); | |
49 | if (pagelen < 0) | |
50 | return (int) pagelen; | |
51 | zeropage = calloc(pagelen, 1); | |
52 | if (!zeropage) | |
53 | return -ENOMEM; | |
54 | ||
55 | while (len > written) { | |
56 | do { | |
57 | retlen = write(fd, zeropage, | |
58 | min_t(size_t, pagelen, len - written)); | |
59 | } while (retlen == -1UL && errno == EINTR); | |
60 | if (retlen < 0) { | |
61 | ret = (int) retlen; | |
62 | goto error; | |
63 | } | |
64 | written += retlen; | |
65 | } | |
66 | ret = 0; | |
67 | error: | |
68 | free(zeropage); | |
69 | return ret; | |
70 | } | |
1d498196 MD |
71 | |
72 | struct shm_object_table *shm_object_table_create(size_t max_nb_obj) | |
73 | { | |
74 | struct shm_object_table *table; | |
75 | ||
76 | table = zmalloc(sizeof(struct shm_object_table) + | |
77 | max_nb_obj * sizeof(table->objects[0])); | |
74d48abe MD |
78 | if (!table) |
79 | return NULL; | |
1d498196 MD |
80 | table->size = max_nb_obj; |
81 | return table; | |
82 | } | |
83 | ||
74d81a6c MD |
84 | static |
85 | struct shm_object *_shm_object_table_alloc_shm(struct shm_object_table *table, | |
a9ff648c | 86 | size_t memory_map_size, |
5ea386c3 | 87 | int stream_fd) |
1d498196 | 88 | { |
5ea386c3 | 89 | int shmfd, waitfd[2], ret, i; |
1d498196 MD |
90 | struct shm_object *obj; |
91 | char *memory_map; | |
92 | ||
5ea386c3 MD |
93 | if (stream_fd < 0) |
94 | return NULL; | |
1d498196 MD |
95 | if (table->allocated_len >= table->size) |
96 | return NULL; | |
7a9c21bd | 97 | obj = &table->objects[table->allocated_len]; |
1d498196 MD |
98 | |
99 | /* wait_fd: create pipe */ | |
100 | ret = pipe(waitfd); | |
101 | if (ret < 0) { | |
102 | PERROR("pipe"); | |
103 | goto error_pipe; | |
104 | } | |
105 | for (i = 0; i < 2; i++) { | |
106 | ret = fcntl(waitfd[i], F_SETFD, FD_CLOEXEC); | |
107 | if (ret < 0) { | |
108 | PERROR("fcntl"); | |
109 | goto error_fcntl; | |
110 | } | |
111 | } | |
5d61a504 MD |
112 | /* The write end of the pipe needs to be non-blocking */ |
113 | ret = fcntl(waitfd[1], F_SETFL, O_NONBLOCK); | |
114 | if (ret < 0) { | |
115 | PERROR("fcntl"); | |
116 | goto error_fcntl; | |
117 | } | |
7a9c21bd | 118 | memcpy(obj->wait_fd, waitfd, sizeof(waitfd)); |
1d498196 | 119 | |
053e6e24 MJ |
120 | /* |
121 | * Set POSIX shared memory object size | |
122 | * | |
123 | * First, use ftruncate() to set its size, some implementations won't | |
124 | * allow writes past the size set by ftruncate. | |
125 | * Then, use write() to fill it with zeros, this allows us to fully | |
126 | * allocate it and detect a shortage of shm space without dealing with | |
127 | * a SIGBUS. | |
128 | */ | |
a9ff648c | 129 | |
5ea386c3 | 130 | shmfd = stream_fd; |
1d498196 MD |
131 | ret = ftruncate(shmfd, memory_map_size); |
132 | if (ret) { | |
133 | PERROR("ftruncate"); | |
134 | goto error_ftruncate; | |
135 | } | |
053e6e24 MJ |
136 | ret = zero_file(shmfd, memory_map_size); |
137 | if (ret) { | |
138 | PERROR("zero_file"); | |
139 | goto error_zero_file; | |
140 | } | |
71be0c53 | 141 | |
d0f6cf57 MD |
142 | /* |
143 | * Also ensure the file metadata is synced with the storage by using | |
71be0c53 MJ |
144 | * fsync(2). Some platforms don't allow fsync on POSIX shm fds, ignore |
145 | * EINVAL accordingly. | |
d0f6cf57 MD |
146 | */ |
147 | ret = fsync(shmfd); | |
71be0c53 | 148 | if (ret && errno != EINVAL) { |
d0f6cf57 MD |
149 | PERROR("fsync"); |
150 | goto error_fsync; | |
151 | } | |
5ea386c3 | 152 | obj->shm_fd_ownership = 0; |
1d498196 MD |
153 | obj->shm_fd = shmfd; |
154 | ||
155 | /* memory_map: mmap */ | |
156 | memory_map = mmap(NULL, memory_map_size, PROT_READ | PROT_WRITE, | |
4d4838ba | 157 | MAP_SHARED | LTTNG_MAP_POPULATE, shmfd, 0); |
1d498196 MD |
158 | if (memory_map == MAP_FAILED) { |
159 | PERROR("mmap"); | |
160 | goto error_mmap; | |
161 | } | |
74d81a6c | 162 | obj->type = SHM_OBJECT_SHM; |
1d498196 MD |
163 | obj->memory_map = memory_map; |
164 | obj->memory_map_size = memory_map_size; | |
165 | obj->allocated_len = 0; | |
dc613eb9 | 166 | obj->index = table->allocated_len++; |
7a9c21bd | 167 | |
1d498196 MD |
168 | return obj; |
169 | ||
170 | error_mmap: | |
d0f6cf57 | 171 | error_fsync: |
1d498196 | 172 | error_ftruncate: |
3a81f31d | 173 | error_zero_file: |
1d498196 MD |
174 | error_fcntl: |
175 | for (i = 0; i < 2; i++) { | |
176 | ret = close(waitfd[i]); | |
177 | if (ret) { | |
178 | PERROR("close"); | |
179 | assert(0); | |
180 | } | |
181 | } | |
182 | error_pipe: | |
1d498196 | 183 | return NULL; |
1d498196 MD |
184 | } |
185 | ||
74d81a6c MD |
186 | static |
187 | struct shm_object *_shm_object_table_alloc_mem(struct shm_object_table *table, | |
188 | size_t memory_map_size) | |
189 | { | |
190 | struct shm_object *obj; | |
191 | void *memory_map; | |
ff0f5728 | 192 | int waitfd[2], i, ret; |
74d81a6c MD |
193 | |
194 | if (table->allocated_len >= table->size) | |
195 | return NULL; | |
196 | obj = &table->objects[table->allocated_len]; | |
197 | ||
198 | memory_map = zmalloc(memory_map_size); | |
199 | if (!memory_map) | |
200 | goto alloc_error; | |
201 | ||
ff0f5728 MD |
202 | /* wait_fd: create pipe */ |
203 | ret = pipe(waitfd); | |
204 | if (ret < 0) { | |
205 | PERROR("pipe"); | |
206 | goto error_pipe; | |
207 | } | |
208 | for (i = 0; i < 2; i++) { | |
209 | ret = fcntl(waitfd[i], F_SETFD, FD_CLOEXEC); | |
210 | if (ret < 0) { | |
211 | PERROR("fcntl"); | |
212 | goto error_fcntl; | |
213 | } | |
214 | } | |
215 | /* The write end of the pipe needs to be non-blocking */ | |
216 | ret = fcntl(waitfd[1], F_SETFL, O_NONBLOCK); | |
217 | if (ret < 0) { | |
218 | PERROR("fcntl"); | |
219 | goto error_fcntl; | |
220 | } | |
221 | memcpy(obj->wait_fd, waitfd, sizeof(waitfd)); | |
222 | ||
223 | /* no shm_fd */ | |
74d81a6c | 224 | obj->shm_fd = -1; |
5ea386c3 | 225 | obj->shm_fd_ownership = 0; |
74d81a6c MD |
226 | |
227 | obj->type = SHM_OBJECT_MEM; | |
228 | obj->memory_map = memory_map; | |
229 | obj->memory_map_size = memory_map_size; | |
230 | obj->allocated_len = 0; | |
231 | obj->index = table->allocated_len++; | |
232 | ||
233 | return obj; | |
234 | ||
ff0f5728 MD |
235 | error_fcntl: |
236 | for (i = 0; i < 2; i++) { | |
237 | ret = close(waitfd[i]); | |
238 | if (ret) { | |
239 | PERROR("close"); | |
240 | assert(0); | |
241 | } | |
242 | } | |
243 | error_pipe: | |
244 | free(memory_map); | |
74d81a6c MD |
245 | alloc_error: |
246 | return NULL; | |
247 | } | |
248 | ||
8a208943 MD |
249 | /* |
250 | * libnuma prints errors on the console even for numa_available(). | |
251 | * Work-around this limitation by using get_mempolicy() directly to | |
252 | * check whether the kernel supports mempolicy. | |
253 | */ | |
254 | #ifdef HAVE_LIBNUMA | |
255 | static bool lttng_is_numa_available(void) | |
256 | { | |
257 | int ret; | |
258 | ||
259 | ret = get_mempolicy(NULL, NULL, 0, NULL, 0); | |
260 | if (ret && errno == ENOSYS) { | |
261 | return false; | |
262 | } | |
263 | return numa_available() > 0; | |
264 | } | |
265 | #endif | |
266 | ||
c494c0f1 | 267 | #ifdef HAVE_LIBNUMA |
74d81a6c MD |
268 | struct shm_object *shm_object_table_alloc(struct shm_object_table *table, |
269 | size_t memory_map_size, | |
a9ff648c | 270 | enum shm_object_type type, |
4b68c31f MD |
271 | int stream_fd, |
272 | int cpu) | |
c494c0f1 MJ |
273 | #else |
274 | struct shm_object *shm_object_table_alloc(struct shm_object_table *table, | |
275 | size_t memory_map_size, | |
276 | enum shm_object_type type, | |
277 | int stream_fd, | |
278 | int cpu __attribute__((unused))) | |
279 | #endif | |
74d81a6c | 280 | { |
4b68c31f | 281 | struct shm_object *shm_object; |
bfcda6ce | 282 | #ifdef HAVE_LIBNUMA |
8a208943 MD |
283 | int oldnode = 0, node; |
284 | bool numa_avail; | |
4b68c31f | 285 | |
8a208943 MD |
286 | numa_avail = lttng_is_numa_available(); |
287 | if (numa_avail) { | |
288 | oldnode = numa_preferred(); | |
289 | if (cpu >= 0) { | |
290 | node = numa_node_of_cpu(cpu); | |
291 | if (node >= 0) | |
292 | numa_set_preferred(node); | |
293 | } | |
294 | if (cpu < 0 || node < 0) | |
295 | numa_set_localalloc(); | |
4b68c31f | 296 | } |
bfcda6ce | 297 | #endif /* HAVE_LIBNUMA */ |
74d81a6c MD |
298 | switch (type) { |
299 | case SHM_OBJECT_SHM: | |
4b68c31f | 300 | shm_object = _shm_object_table_alloc_shm(table, memory_map_size, |
5ea386c3 | 301 | stream_fd); |
4b68c31f | 302 | break; |
74d81a6c | 303 | case SHM_OBJECT_MEM: |
4b68c31f MD |
304 | shm_object = _shm_object_table_alloc_mem(table, memory_map_size); |
305 | break; | |
74d81a6c MD |
306 | default: |
307 | assert(0); | |
308 | } | |
bfcda6ce | 309 | #ifdef HAVE_LIBNUMA |
8a208943 MD |
310 | if (numa_avail) |
311 | numa_set_preferred(oldnode); | |
bfcda6ce | 312 | #endif /* HAVE_LIBNUMA */ |
4b68c31f | 313 | return shm_object; |
74d81a6c MD |
314 | } |
315 | ||
316 | struct shm_object *shm_object_table_append_shm(struct shm_object_table *table, | |
317 | int shm_fd, int wakeup_fd, uint32_t stream_nr, | |
318 | size_t memory_map_size) | |
193183fb MD |
319 | { |
320 | struct shm_object *obj; | |
321 | char *memory_map; | |
74d81a6c | 322 | int ret; |
193183fb MD |
323 | |
324 | if (table->allocated_len >= table->size) | |
325 | return NULL; | |
74d81a6c MD |
326 | /* streams _must_ be received in sequential order, else fail. */ |
327 | if (stream_nr + 1 != table->allocated_len) | |
328 | return NULL; | |
329 | ||
193183fb MD |
330 | obj = &table->objects[table->allocated_len]; |
331 | ||
74d81a6c MD |
332 | /* wait_fd: set write end of the pipe. */ |
333 | obj->wait_fd[0] = -1; /* read end is unset */ | |
334 | obj->wait_fd[1] = wakeup_fd; | |
193183fb | 335 | obj->shm_fd = shm_fd; |
5ea386c3 | 336 | obj->shm_fd_ownership = 1; |
193183fb | 337 | |
74d81a6c MD |
338 | /* The write end of the pipe needs to be non-blocking */ |
339 | ret = fcntl(obj->wait_fd[1], F_SETFL, O_NONBLOCK); | |
340 | if (ret < 0) { | |
341 | PERROR("fcntl"); | |
342 | goto error_fcntl; | |
343 | } | |
344 | ||
193183fb MD |
345 | /* memory_map: mmap */ |
346 | memory_map = mmap(NULL, memory_map_size, PROT_READ | PROT_WRITE, | |
4d4838ba | 347 | MAP_SHARED | LTTNG_MAP_POPULATE, shm_fd, 0); |
193183fb MD |
348 | if (memory_map == MAP_FAILED) { |
349 | PERROR("mmap"); | |
350 | goto error_mmap; | |
351 | } | |
74d81a6c | 352 | obj->type = SHM_OBJECT_SHM; |
193183fb MD |
353 | obj->memory_map = memory_map; |
354 | obj->memory_map_size = memory_map_size; | |
355 | obj->allocated_len = memory_map_size; | |
356 | obj->index = table->allocated_len++; | |
357 | ||
358 | return obj; | |
359 | ||
74d81a6c | 360 | error_fcntl: |
193183fb MD |
361 | error_mmap: |
362 | return NULL; | |
363 | } | |
364 | ||
74d81a6c MD |
365 | /* |
366 | * Passing ownership of mem to object. | |
367 | */ | |
368 | struct shm_object *shm_object_table_append_mem(struct shm_object_table *table, | |
ff0f5728 | 369 | void *mem, size_t memory_map_size, int wakeup_fd) |
74d81a6c MD |
370 | { |
371 | struct shm_object *obj; | |
ff0f5728 | 372 | int ret; |
74d81a6c MD |
373 | |
374 | if (table->allocated_len >= table->size) | |
375 | return NULL; | |
376 | obj = &table->objects[table->allocated_len]; | |
377 | ||
ff0f5728 MD |
378 | obj->wait_fd[0] = -1; /* read end is unset */ |
379 | obj->wait_fd[1] = wakeup_fd; | |
74d81a6c | 380 | obj->shm_fd = -1; |
5ea386c3 | 381 | obj->shm_fd_ownership = 0; |
74d81a6c | 382 | |
ff0f5728 MD |
383 | ret = fcntl(obj->wait_fd[1], F_SETFD, FD_CLOEXEC); |
384 | if (ret < 0) { | |
385 | PERROR("fcntl"); | |
386 | goto error_fcntl; | |
387 | } | |
388 | /* The write end of the pipe needs to be non-blocking */ | |
389 | ret = fcntl(obj->wait_fd[1], F_SETFL, O_NONBLOCK); | |
390 | if (ret < 0) { | |
391 | PERROR("fcntl"); | |
392 | goto error_fcntl; | |
393 | } | |
394 | ||
74d81a6c MD |
395 | obj->type = SHM_OBJECT_MEM; |
396 | obj->memory_map = mem; | |
397 | obj->memory_map_size = memory_map_size; | |
398 | obj->allocated_len = memory_map_size; | |
399 | obj->index = table->allocated_len++; | |
400 | ||
401 | return obj; | |
ff0f5728 MD |
402 | |
403 | error_fcntl: | |
404 | return NULL; | |
74d81a6c MD |
405 | } |
406 | ||
1d498196 | 407 | static |
6548fca4 | 408 | void shmp_object_destroy(struct shm_object *obj, int consumer) |
1d498196 | 409 | { |
74d81a6c MD |
410 | switch (obj->type) { |
411 | case SHM_OBJECT_SHM: | |
412 | { | |
413 | int ret, i; | |
1d498196 | 414 | |
7a784989 MD |
415 | ret = munmap(obj->memory_map, obj->memory_map_size); |
416 | if (ret) { | |
417 | PERROR("umnmap"); | |
418 | assert(0); | |
419 | } | |
6548fca4 | 420 | |
5ea386c3 | 421 | if (obj->shm_fd_ownership) { |
6548fca4 MD |
422 | /* Delete FDs only if called from app (not consumer). */ |
423 | if (!consumer) { | |
424 | lttng_ust_lock_fd_tracker(); | |
425 | ret = close(obj->shm_fd); | |
426 | if (!ret) { | |
427 | lttng_ust_delete_fd_from_tracker(obj->shm_fd); | |
428 | } else { | |
429 | PERROR("close"); | |
430 | assert(0); | |
431 | } | |
432 | lttng_ust_unlock_fd_tracker(); | |
433 | } else { | |
434 | ret = close(obj->shm_fd); | |
435 | if (ret) { | |
436 | PERROR("close"); | |
437 | assert(0); | |
438 | } | |
a9ff648c MD |
439 | } |
440 | } | |
74d81a6c MD |
441 | for (i = 0; i < 2; i++) { |
442 | if (obj->wait_fd[i] < 0) | |
443 | continue; | |
6548fca4 MD |
444 | if (!consumer) { |
445 | lttng_ust_lock_fd_tracker(); | |
446 | ret = close(obj->wait_fd[i]); | |
447 | if (!ret) { | |
448 | lttng_ust_delete_fd_from_tracker(obj->wait_fd[i]); | |
449 | } else { | |
450 | PERROR("close"); | |
451 | assert(0); | |
452 | } | |
453 | lttng_ust_unlock_fd_tracker(); | |
454 | } else { | |
455 | ret = close(obj->wait_fd[i]); | |
456 | if (ret) { | |
457 | PERROR("close"); | |
458 | assert(0); | |
459 | } | |
74d81a6c | 460 | } |
1d498196 | 461 | } |
74d81a6c MD |
462 | break; |
463 | } | |
464 | case SHM_OBJECT_MEM: | |
ff0f5728 MD |
465 | { |
466 | int ret, i; | |
467 | ||
468 | for (i = 0; i < 2; i++) { | |
469 | if (obj->wait_fd[i] < 0) | |
470 | continue; | |
6548fca4 MD |
471 | if (!consumer) { |
472 | lttng_ust_lock_fd_tracker(); | |
473 | ret = close(obj->wait_fd[i]); | |
474 | if (!ret) { | |
475 | lttng_ust_delete_fd_from_tracker(obj->wait_fd[i]); | |
476 | } else { | |
477 | PERROR("close"); | |
478 | assert(0); | |
479 | } | |
480 | lttng_ust_unlock_fd_tracker(); | |
481 | } else { | |
482 | ret = close(obj->wait_fd[i]); | |
483 | if (ret) { | |
484 | PERROR("close"); | |
485 | assert(0); | |
486 | } | |
ff0f5728 MD |
487 | } |
488 | } | |
74d81a6c MD |
489 | free(obj->memory_map); |
490 | break; | |
ff0f5728 | 491 | } |
74d81a6c MD |
492 | default: |
493 | assert(0); | |
1d498196 MD |
494 | } |
495 | } | |
496 | ||
6548fca4 | 497 | void shm_object_table_destroy(struct shm_object_table *table, int consumer) |
1d498196 MD |
498 | { |
499 | int i; | |
500 | ||
501 | for (i = 0; i < table->allocated_len; i++) | |
6548fca4 | 502 | shmp_object_destroy(&table->objects[i], consumer); |
1d498196 MD |
503 | free(table); |
504 | } | |
505 | ||
506 | /* | |
507 | * zalloc_shm - allocate memory within a shm object. | |
508 | * | |
509 | * Shared memory is already zeroed by shmget. | |
510 | * *NOT* multithread-safe (should be protected by mutex). | |
511 | * Returns a -1, -1 tuple on error. | |
512 | */ | |
513 | struct shm_ref zalloc_shm(struct shm_object *obj, size_t len) | |
514 | { | |
515 | struct shm_ref ref; | |
516 | struct shm_ref shm_ref_error = { -1, -1 }; | |
517 | ||
518 | if (obj->memory_map_size - obj->allocated_len < len) | |
519 | return shm_ref_error; | |
520 | ref.index = obj->index; | |
521 | ref.offset = obj->allocated_len; | |
522 | obj->allocated_len += len; | |
523 | return ref; | |
524 | } | |
525 | ||
526 | void align_shm(struct shm_object *obj, size_t align) | |
527 | { | |
b72687b8 | 528 | size_t offset_len = lttng_ust_offset_align(obj->allocated_len, align); |
1d498196 MD |
529 | obj->allocated_len += offset_len; |
530 | } |