Dhoat Harpal | f76b236 | 2018-03-22 20:37:38 +0530 | [diff] [blame] | 1 | /* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved. |
Karthikeyan Ramasubramanian | 44dc770 | 2016-09-16 15:39:37 -0600 | [diff] [blame] | 2 | * |
| 3 | * This program is free software; you can redistribute it and/or modify |
| 4 | * it under the terms of the GNU General Public License version 2 and |
| 5 | * only version 2 as published by the Free Software Foundation. |
| 6 | * |
| 7 | * This program is distributed in the hope that it will be useful, |
| 8 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 9 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 10 | * GNU General Public License for more details. |
| 11 | * |
| 12 | */ |
| 13 | |
| 14 | #include <asm/arch_timer.h> |
| 15 | #include <linux/slab.h> |
| 16 | #include <linux/uaccess.h> |
| 17 | #include <linux/module.h> |
| 18 | #include <linux/fs.h> |
| 19 | #include <linux/kernel.h> |
| 20 | #include <linux/errno.h> |
| 21 | #include <linux/jiffies.h> |
| 22 | #include <linux/debugfs.h> |
| 23 | #include <linux/io.h> |
| 24 | #include <linux/idr.h> |
| 25 | #include <linux/string.h> |
| 26 | #include <linux/sched.h> |
| 27 | #include <linux/wait.h> |
| 28 | #include <linux/delay.h> |
| 29 | #include <linux/completion.h> |
| 30 | #include <linux/ipc_logging.h> |
| 31 | |
| 32 | #include "ipc_logging_private.h" |
| 33 | |
| 34 | #define LOG_PAGE_DATA_SIZE sizeof(((struct ipc_log_page *)0)->data) |
| 35 | #define LOG_PAGE_FLAG (1 << 31) |
| 36 | |
| 37 | static LIST_HEAD(ipc_log_context_list); |
| 38 | static DEFINE_RWLOCK(context_list_lock_lha1); |
| 39 | static void *get_deserialization_func(struct ipc_log_context *ilctxt, |
| 40 | int type); |
| 41 | |
| 42 | static struct ipc_log_page *get_first_page(struct ipc_log_context *ilctxt) |
| 43 | { |
| 44 | struct ipc_log_page_header *p_pghdr; |
| 45 | struct ipc_log_page *pg = NULL; |
| 46 | |
| 47 | if (!ilctxt) |
| 48 | return NULL; |
| 49 | p_pghdr = list_first_entry(&ilctxt->page_list, |
| 50 | struct ipc_log_page_header, list); |
| 51 | pg = container_of(p_pghdr, struct ipc_log_page, hdr); |
| 52 | return pg; |
| 53 | } |
| 54 | |
| 55 | /** |
| 56 | * is_nd_read_empty - Returns true if no data is available to read in log |
| 57 | * |
| 58 | * @ilctxt: logging context |
| 59 | * @returns: > 1 if context is empty; 0 if not empty; <0 for failure |
| 60 | * |
| 61 | * This is for the debugfs read pointer which allows for a non-destructive read. |
| 62 | * There may still be data in the log, but it may have already been read. |
| 63 | */ |
| 64 | static int is_nd_read_empty(struct ipc_log_context *ilctxt) |
| 65 | { |
| 66 | if (!ilctxt) |
| 67 | return -EINVAL; |
| 68 | |
| 69 | return ((ilctxt->nd_read_page == ilctxt->write_page) && |
| 70 | (ilctxt->nd_read_page->hdr.nd_read_offset == |
| 71 | ilctxt->write_page->hdr.write_offset)); |
| 72 | } |
| 73 | |
| 74 | /** |
| 75 | * is_read_empty - Returns true if no data is available in log |
| 76 | * |
| 77 | * @ilctxt: logging context |
| 78 | * @returns: > 1 if context is empty; 0 if not empty; <0 for failure |
| 79 | * |
| 80 | * This is for the actual log contents. If it is empty, then there |
| 81 | * is no data at all in the log. |
| 82 | */ |
| 83 | static int is_read_empty(struct ipc_log_context *ilctxt) |
| 84 | { |
| 85 | if (!ilctxt) |
| 86 | return -EINVAL; |
| 87 | |
| 88 | return ((ilctxt->read_page == ilctxt->write_page) && |
| 89 | (ilctxt->read_page->hdr.read_offset == |
| 90 | ilctxt->write_page->hdr.write_offset)); |
| 91 | } |
| 92 | |
| 93 | /** |
| 94 | * is_nd_read_equal_read - Return true if the non-destructive read is equal to |
| 95 | * the destructive read |
| 96 | * |
| 97 | * @ilctxt: logging context |
| 98 | * @returns: true if nd read is equal to read; false otherwise |
| 99 | */ |
| 100 | static bool is_nd_read_equal_read(struct ipc_log_context *ilctxt) |
| 101 | { |
| 102 | uint16_t read_offset; |
| 103 | uint16_t nd_read_offset; |
| 104 | |
| 105 | if (ilctxt->nd_read_page == ilctxt->read_page) { |
| 106 | read_offset = ilctxt->read_page->hdr.read_offset; |
| 107 | nd_read_offset = ilctxt->nd_read_page->hdr.nd_read_offset; |
| 108 | |
| 109 | if (read_offset == nd_read_offset) |
| 110 | return true; |
| 111 | } |
| 112 | |
| 113 | return false; |
| 114 | } |
| 115 | |
| 116 | |
| 117 | static struct ipc_log_page *get_next_page(struct ipc_log_context *ilctxt, |
| 118 | struct ipc_log_page *cur_pg) |
| 119 | { |
| 120 | struct ipc_log_page_header *p_pghdr; |
| 121 | struct ipc_log_page *pg = NULL; |
| 122 | |
| 123 | if (!ilctxt || !cur_pg) |
| 124 | return NULL; |
| 125 | |
| 126 | if (ilctxt->last_page == cur_pg) |
| 127 | return ilctxt->first_page; |
| 128 | |
| 129 | p_pghdr = list_first_entry(&cur_pg->hdr.list, |
| 130 | struct ipc_log_page_header, list); |
| 131 | pg = container_of(p_pghdr, struct ipc_log_page, hdr); |
| 132 | |
| 133 | return pg; |
| 134 | } |
| 135 | |
| 136 | /** |
| 137 | * ipc_log_read - do non-destructive read of the log |
| 138 | * |
| 139 | * @ilctxt: Logging context |
| 140 | * @data: Data pointer to receive the data |
| 141 | * @data_size: Number of bytes to read (must be <= bytes available in log) |
| 142 | * |
| 143 | * This read will update a runtime read pointer, but will not affect the actual |
| 144 | * contents of the log which allows for reading the logs continuously while |
| 145 | * debugging and if the system crashes, then the full logs can still be |
| 146 | * extracted. |
| 147 | */ |
| 148 | static void ipc_log_read(struct ipc_log_context *ilctxt, |
| 149 | void *data, int data_size) |
| 150 | { |
| 151 | int bytes_to_read; |
| 152 | |
| 153 | bytes_to_read = MIN(LOG_PAGE_DATA_SIZE |
| 154 | - ilctxt->nd_read_page->hdr.nd_read_offset, |
| 155 | data_size); |
| 156 | |
| 157 | memcpy(data, (ilctxt->nd_read_page->data + |
| 158 | ilctxt->nd_read_page->hdr.nd_read_offset), bytes_to_read); |
| 159 | |
| 160 | if (bytes_to_read != data_size) { |
| 161 | /* not enough space, wrap read to next page */ |
| 162 | ilctxt->nd_read_page->hdr.nd_read_offset = 0; |
| 163 | ilctxt->nd_read_page = get_next_page(ilctxt, |
| 164 | ilctxt->nd_read_page); |
| 165 | if (WARN_ON(ilctxt->nd_read_page == NULL)) |
| 166 | return; |
| 167 | |
| 168 | memcpy((data + bytes_to_read), |
| 169 | (ilctxt->nd_read_page->data + |
| 170 | ilctxt->nd_read_page->hdr.nd_read_offset), |
| 171 | (data_size - bytes_to_read)); |
| 172 | bytes_to_read = (data_size - bytes_to_read); |
| 173 | } |
| 174 | ilctxt->nd_read_page->hdr.nd_read_offset += bytes_to_read; |
| 175 | } |
| 176 | |
| 177 | /** |
| 178 | * ipc_log_drop - do destructive read of the log |
| 179 | * |
| 180 | * @ilctxt: Logging context |
| 181 | * @data: Data pointer to receive the data (or NULL) |
| 182 | * @data_size: Number of bytes to read (must be <= bytes available in log) |
| 183 | */ |
| 184 | static void ipc_log_drop(struct ipc_log_context *ilctxt, void *data, |
| 185 | int data_size) |
| 186 | { |
| 187 | int bytes_to_read; |
| 188 | bool push_nd_read; |
| 189 | |
| 190 | bytes_to_read = MIN(LOG_PAGE_DATA_SIZE |
| 191 | - ilctxt->read_page->hdr.read_offset, |
| 192 | data_size); |
| 193 | if (data) |
| 194 | memcpy(data, (ilctxt->read_page->data + |
| 195 | ilctxt->read_page->hdr.read_offset), bytes_to_read); |
| 196 | |
| 197 | if (bytes_to_read != data_size) { |
| 198 | /* not enough space, wrap read to next page */ |
| 199 | push_nd_read = is_nd_read_equal_read(ilctxt); |
| 200 | |
| 201 | ilctxt->read_page->hdr.read_offset = 0; |
| 202 | if (push_nd_read) { |
| 203 | ilctxt->read_page->hdr.nd_read_offset = 0; |
| 204 | ilctxt->read_page = get_next_page(ilctxt, |
| 205 | ilctxt->read_page); |
| 206 | if (WARN_ON(ilctxt->read_page == NULL)) |
| 207 | return; |
| 208 | ilctxt->nd_read_page = ilctxt->read_page; |
| 209 | } else { |
| 210 | ilctxt->read_page = get_next_page(ilctxt, |
| 211 | ilctxt->read_page); |
| 212 | if (WARN_ON(ilctxt->read_page == NULL)) |
| 213 | return; |
| 214 | } |
| 215 | |
| 216 | if (data) |
| 217 | memcpy((data + bytes_to_read), |
| 218 | (ilctxt->read_page->data + |
| 219 | ilctxt->read_page->hdr.read_offset), |
| 220 | (data_size - bytes_to_read)); |
| 221 | |
| 222 | bytes_to_read = (data_size - bytes_to_read); |
| 223 | } |
| 224 | |
| 225 | /* update non-destructive read pointer if necessary */ |
| 226 | push_nd_read = is_nd_read_equal_read(ilctxt); |
| 227 | ilctxt->read_page->hdr.read_offset += bytes_to_read; |
| 228 | ilctxt->write_avail += data_size; |
| 229 | |
| 230 | if (push_nd_read) |
| 231 | ilctxt->nd_read_page->hdr.nd_read_offset += bytes_to_read; |
| 232 | } |
| 233 | |
| 234 | /** |
| 235 | * msg_read - Reads a message. |
| 236 | * |
| 237 | * If a message is read successfully, then the message context |
| 238 | * will be set to: |
| 239 | * .hdr message header .size and .type values |
| 240 | * .offset beginning of message data |
| 241 | * |
| 242 | * @ilctxt Logging context |
| 243 | * @ectxt Message context |
| 244 | * |
| 245 | * @returns 0 - no message available; >0 message size; <0 error |
| 246 | */ |
| 247 | static int msg_read(struct ipc_log_context *ilctxt, |
| 248 | struct encode_context *ectxt) |
| 249 | { |
| 250 | struct tsv_header hdr; |
| 251 | |
| 252 | if (!ectxt) |
| 253 | return -EINVAL; |
| 254 | |
| 255 | if (is_nd_read_empty(ilctxt)) |
| 256 | return 0; |
| 257 | |
| 258 | ipc_log_read(ilctxt, &hdr, sizeof(hdr)); |
| 259 | ectxt->hdr.type = hdr.type; |
| 260 | ectxt->hdr.size = hdr.size; |
| 261 | ectxt->offset = sizeof(hdr); |
| 262 | ipc_log_read(ilctxt, (ectxt->buff + ectxt->offset), |
| 263 | (int)hdr.size); |
| 264 | |
| 265 | return sizeof(hdr) + (int)hdr.size; |
| 266 | } |
| 267 | |
| 268 | /** |
| 269 | * msg_drop - Drops a message. |
| 270 | * |
| 271 | * @ilctxt Logging context |
| 272 | */ |
| 273 | static void msg_drop(struct ipc_log_context *ilctxt) |
| 274 | { |
| 275 | struct tsv_header hdr; |
| 276 | |
| 277 | if (!is_read_empty(ilctxt)) { |
| 278 | ipc_log_drop(ilctxt, &hdr, sizeof(hdr)); |
| 279 | ipc_log_drop(ilctxt, NULL, (int)hdr.size); |
| 280 | } |
| 281 | } |
| 282 | |
| 283 | /* |
| 284 | * Commits messages to the FIFO. If the FIFO is full, then enough |
| 285 | * messages are dropped to create space for the new message. |
| 286 | */ |
| 287 | void ipc_log_write(void *ctxt, struct encode_context *ectxt) |
| 288 | { |
| 289 | struct ipc_log_context *ilctxt = (struct ipc_log_context *)ctxt; |
| 290 | int bytes_to_write; |
| 291 | unsigned long flags; |
| 292 | |
| 293 | if (!ilctxt || !ectxt) { |
| 294 | pr_err("%s: Invalid ipc_log or encode context\n", __func__); |
| 295 | return; |
| 296 | } |
| 297 | |
Dhoat Harpal | f76b236 | 2018-03-22 20:37:38 +0530 | [diff] [blame] | 298 | if (ilctxt->disabled) |
| 299 | return; |
Karthikeyan Ramasubramanian | 44dc770 | 2016-09-16 15:39:37 -0600 | [diff] [blame] | 300 | read_lock_irqsave(&context_list_lock_lha1, flags); |
| 301 | spin_lock(&ilctxt->context_lock_lhb1); |
| 302 | while (ilctxt->write_avail <= ectxt->offset) |
| 303 | msg_drop(ilctxt); |
| 304 | |
| 305 | bytes_to_write = MIN(LOG_PAGE_DATA_SIZE |
| 306 | - ilctxt->write_page->hdr.write_offset, |
| 307 | ectxt->offset); |
| 308 | memcpy((ilctxt->write_page->data + |
| 309 | ilctxt->write_page->hdr.write_offset), |
| 310 | ectxt->buff, bytes_to_write); |
| 311 | |
| 312 | if (bytes_to_write != ectxt->offset) { |
| 313 | uint64_t t_now = sched_clock(); |
| 314 | |
| 315 | ilctxt->write_page->hdr.write_offset += bytes_to_write; |
| 316 | ilctxt->write_page->hdr.end_time = t_now; |
| 317 | |
| 318 | ilctxt->write_page = get_next_page(ilctxt, ilctxt->write_page); |
Chris Lew | 273eea68 | 2017-06-15 18:35:11 -0700 | [diff] [blame] | 319 | if (WARN_ON(ilctxt->write_page == NULL)) { |
| 320 | spin_unlock(&ilctxt->context_lock_lhb1); |
| 321 | read_unlock_irqrestore(&context_list_lock_lha1, flags); |
Karthikeyan Ramasubramanian | 44dc770 | 2016-09-16 15:39:37 -0600 | [diff] [blame] | 322 | return; |
Chris Lew | 273eea68 | 2017-06-15 18:35:11 -0700 | [diff] [blame] | 323 | } |
Karthikeyan Ramasubramanian | 44dc770 | 2016-09-16 15:39:37 -0600 | [diff] [blame] | 324 | ilctxt->write_page->hdr.write_offset = 0; |
| 325 | ilctxt->write_page->hdr.start_time = t_now; |
| 326 | memcpy((ilctxt->write_page->data + |
| 327 | ilctxt->write_page->hdr.write_offset), |
| 328 | (ectxt->buff + bytes_to_write), |
| 329 | (ectxt->offset - bytes_to_write)); |
| 330 | bytes_to_write = (ectxt->offset - bytes_to_write); |
| 331 | } |
| 332 | ilctxt->write_page->hdr.write_offset += bytes_to_write; |
| 333 | ilctxt->write_avail -= ectxt->offset; |
| 334 | complete(&ilctxt->read_avail); |
| 335 | spin_unlock(&ilctxt->context_lock_lhb1); |
| 336 | read_unlock_irqrestore(&context_list_lock_lha1, flags); |
| 337 | } |
| 338 | EXPORT_SYMBOL(ipc_log_write); |
| 339 | |
| 340 | /* |
| 341 | * Starts a new message after which you can add serialized data and |
| 342 | * then complete the message by calling msg_encode_end(). |
| 343 | */ |
| 344 | void msg_encode_start(struct encode_context *ectxt, uint32_t type) |
| 345 | { |
| 346 | if (!ectxt) { |
| 347 | pr_err("%s: Invalid encode context\n", __func__); |
| 348 | return; |
| 349 | } |
| 350 | |
| 351 | ectxt->hdr.type = type; |
| 352 | ectxt->hdr.size = 0; |
| 353 | ectxt->offset = sizeof(ectxt->hdr); |
| 354 | } |
| 355 | EXPORT_SYMBOL(msg_encode_start); |
| 356 | |
| 357 | /* |
| 358 | * Completes the message |
| 359 | */ |
| 360 | void msg_encode_end(struct encode_context *ectxt) |
| 361 | { |
| 362 | if (!ectxt) { |
| 363 | pr_err("%s: Invalid encode context\n", __func__); |
| 364 | return; |
| 365 | } |
| 366 | |
| 367 | /* finalize data size */ |
| 368 | ectxt->hdr.size = ectxt->offset - sizeof(ectxt->hdr); |
| 369 | if (WARN_ON(ectxt->hdr.size > MAX_MSG_SIZE)) |
| 370 | return; |
| 371 | memcpy(ectxt->buff, &ectxt->hdr, sizeof(ectxt->hdr)); |
| 372 | } |
| 373 | EXPORT_SYMBOL(msg_encode_end); |
| 374 | |
| 375 | /* |
| 376 | * Helper function used to write data to a message context. |
| 377 | * |
| 378 | * @ectxt context initialized by calling msg_encode_start() |
| 379 | * @data data to write |
| 380 | * @size number of bytes of data to write |
| 381 | */ |
| 382 | static inline int tsv_write_data(struct encode_context *ectxt, |
| 383 | void *data, uint32_t size) |
| 384 | { |
| 385 | if (!ectxt) { |
| 386 | pr_err("%s: Invalid encode context\n", __func__); |
| 387 | return -EINVAL; |
| 388 | } |
| 389 | if ((ectxt->offset + size) > MAX_MSG_SIZE) { |
| 390 | pr_err("%s: No space to encode further\n", __func__); |
| 391 | return -EINVAL; |
| 392 | } |
| 393 | |
| 394 | memcpy((void *)(ectxt->buff + ectxt->offset), data, size); |
| 395 | ectxt->offset += size; |
| 396 | return 0; |
| 397 | } |
| 398 | |
| 399 | /* |
| 400 | * Helper function that writes a type to the context. |
| 401 | * |
| 402 | * @ectxt context initialized by calling msg_encode_start() |
| 403 | * @type primitive type |
| 404 | * @size size of primitive in bytes |
| 405 | */ |
| 406 | static inline int tsv_write_header(struct encode_context *ectxt, |
| 407 | uint32_t type, uint32_t size) |
| 408 | { |
| 409 | struct tsv_header hdr; |
| 410 | |
| 411 | hdr.type = (unsigned char)type; |
| 412 | hdr.size = (unsigned char)size; |
| 413 | return tsv_write_data(ectxt, &hdr, sizeof(hdr)); |
| 414 | } |
| 415 | |
| 416 | /* |
| 417 | * Writes the current timestamp count. |
| 418 | * |
| 419 | * @ectxt context initialized by calling msg_encode_start() |
| 420 | */ |
| 421 | int tsv_timestamp_write(struct encode_context *ectxt) |
| 422 | { |
| 423 | int ret; |
| 424 | uint64_t t_now = sched_clock(); |
| 425 | |
| 426 | ret = tsv_write_header(ectxt, TSV_TYPE_TIMESTAMP, sizeof(t_now)); |
| 427 | if (ret) |
| 428 | return ret; |
| 429 | return tsv_write_data(ectxt, &t_now, sizeof(t_now)); |
| 430 | } |
| 431 | EXPORT_SYMBOL(tsv_timestamp_write); |
| 432 | |
| 433 | /* |
| 434 | * Writes the current QTimer timestamp count. |
| 435 | * |
| 436 | * @ectxt context initialized by calling msg_encode_start() |
| 437 | */ |
| 438 | int tsv_qtimer_write(struct encode_context *ectxt) |
| 439 | { |
| 440 | int ret; |
| 441 | uint64_t t_now = arch_counter_get_cntvct(); |
| 442 | |
| 443 | ret = tsv_write_header(ectxt, TSV_TYPE_QTIMER, sizeof(t_now)); |
| 444 | if (ret) |
| 445 | return ret; |
| 446 | return tsv_write_data(ectxt, &t_now, sizeof(t_now)); |
| 447 | } |
| 448 | EXPORT_SYMBOL(tsv_qtimer_write); |
| 449 | |
| 450 | /* |
| 451 | * Writes a data pointer. |
| 452 | * |
| 453 | * @ectxt context initialized by calling msg_encode_start() |
| 454 | * @pointer pointer value to write |
| 455 | */ |
| 456 | int tsv_pointer_write(struct encode_context *ectxt, void *pointer) |
| 457 | { |
| 458 | int ret; |
| 459 | |
| 460 | ret = tsv_write_header(ectxt, TSV_TYPE_POINTER, sizeof(pointer)); |
| 461 | if (ret) |
| 462 | return ret; |
| 463 | return tsv_write_data(ectxt, &pointer, sizeof(pointer)); |
| 464 | } |
| 465 | EXPORT_SYMBOL(tsv_pointer_write); |
| 466 | |
| 467 | /* |
| 468 | * Writes a 32-bit integer value. |
| 469 | * |
| 470 | * @ectxt context initialized by calling msg_encode_start() |
| 471 | * @n integer to write |
| 472 | */ |
| 473 | int tsv_int32_write(struct encode_context *ectxt, int32_t n) |
| 474 | { |
| 475 | int ret; |
| 476 | |
| 477 | ret = tsv_write_header(ectxt, TSV_TYPE_INT32, sizeof(n)); |
| 478 | if (ret) |
| 479 | return ret; |
| 480 | return tsv_write_data(ectxt, &n, sizeof(n)); |
| 481 | } |
| 482 | EXPORT_SYMBOL(tsv_int32_write); |
| 483 | |
| 484 | /* |
| 485 | * Writes a byte array. |
| 486 | * |
| 487 | * @ectxt context initialized by calling msg_write_start() |
| 488 | * @data Beginning address of data |
| 489 | * @data_size Size of data to be written |
| 490 | */ |
| 491 | int tsv_byte_array_write(struct encode_context *ectxt, |
| 492 | void *data, int data_size) |
| 493 | { |
| 494 | int ret; |
| 495 | |
| 496 | ret = tsv_write_header(ectxt, TSV_TYPE_BYTE_ARRAY, data_size); |
| 497 | if (ret) |
| 498 | return ret; |
| 499 | return tsv_write_data(ectxt, data, data_size); |
| 500 | } |
| 501 | EXPORT_SYMBOL(tsv_byte_array_write); |
| 502 | |
| 503 | /* |
| 504 | * Helper function to log a string |
| 505 | * |
| 506 | * @ilctxt ipc_log_context created using ipc_log_context_create() |
| 507 | * @fmt Data specified using format specifiers |
| 508 | */ |
| 509 | int ipc_log_string(void *ilctxt, const char *fmt, ...) |
| 510 | { |
| 511 | struct encode_context ectxt; |
| 512 | int avail_size, data_size, hdr_size = sizeof(struct tsv_header); |
Dhoat Harpal | f76b236 | 2018-03-22 20:37:38 +0530 | [diff] [blame] | 513 | struct ipc_log_context *ctxt = (struct ipc_log_context *)ilctxt; |
Karthikeyan Ramasubramanian | 44dc770 | 2016-09-16 15:39:37 -0600 | [diff] [blame] | 514 | va_list arg_list; |
| 515 | |
| 516 | if (!ilctxt) |
| 517 | return -EINVAL; |
| 518 | |
Dhoat Harpal | f76b236 | 2018-03-22 20:37:38 +0530 | [diff] [blame] | 519 | if (ctxt->disabled) |
| 520 | return -EBUSY; |
Karthikeyan Ramasubramanian | 44dc770 | 2016-09-16 15:39:37 -0600 | [diff] [blame] | 521 | msg_encode_start(&ectxt, TSV_TYPE_STRING); |
| 522 | tsv_timestamp_write(&ectxt); |
| 523 | tsv_qtimer_write(&ectxt); |
| 524 | avail_size = (MAX_MSG_SIZE - (ectxt.offset + hdr_size)); |
| 525 | va_start(arg_list, fmt); |
Jack Pham | f123c9a | 2017-03-30 09:53:53 -0700 | [diff] [blame] | 526 | data_size = vscnprintf((ectxt.buff + ectxt.offset + hdr_size), |
| 527 | avail_size, fmt, arg_list); |
Karthikeyan Ramasubramanian | 44dc770 | 2016-09-16 15:39:37 -0600 | [diff] [blame] | 528 | va_end(arg_list); |
| 529 | tsv_write_header(&ectxt, TSV_TYPE_BYTE_ARRAY, data_size); |
| 530 | ectxt.offset += data_size; |
| 531 | msg_encode_end(&ectxt); |
| 532 | ipc_log_write(ilctxt, &ectxt); |
| 533 | return 0; |
| 534 | } |
| 535 | EXPORT_SYMBOL(ipc_log_string); |
| 536 | |
Dhoat Harpal | f76b236 | 2018-03-22 20:37:38 +0530 | [diff] [blame] | 537 | /* |
| 538 | * ipc_log_ctrl_all - disable/enable logging in all clients |
| 539 | * |
| 540 | * @ Data specified using format specifiers |
| 541 | */ |
| 542 | void ipc_log_ctrl_all(bool disable) |
| 543 | { |
| 544 | struct ipc_log_context *ctxt = NULL; |
| 545 | unsigned long flags; |
| 546 | |
| 547 | read_lock_irqsave(&context_list_lock_lha1, flags); |
| 548 | list_for_each_entry(ctxt, &ipc_log_context_list, list) { |
| 549 | if (disable) { |
| 550 | ipc_log_string(ctxt, |
| 551 | "LOGGING DISABLED FOR ALL CLIENTS!!\n"); |
| 552 | ctxt->disabled = disable; |
| 553 | } else { |
| 554 | ctxt->disabled = disable; |
| 555 | ipc_log_string(ctxt, |
| 556 | "LOGGING ENABLED FOR ALL CLIENTS!!\n"); |
| 557 | } |
| 558 | } |
| 559 | read_unlock_irqrestore(&context_list_lock_lha1, flags); |
| 560 | } |
| 561 | EXPORT_SYMBOL(ipc_log_ctrl_all); |
| 562 | |
Karthikeyan Ramasubramanian | 44dc770 | 2016-09-16 15:39:37 -0600 | [diff] [blame] | 563 | /** |
| 564 | * ipc_log_extract - Reads and deserializes log |
| 565 | * |
| 566 | * @ctxt: logging context |
| 567 | * @buff: buffer to receive the data |
| 568 | * @size: size of the buffer |
| 569 | * @returns: 0 if no data read; >0 number of bytes read; < 0 error |
| 570 | * |
| 571 | * If no data is available to be read, then the ilctxt::read_avail |
| 572 | * completion is reinitialized. This allows clients to block |
| 573 | * until new log data is save. |
| 574 | */ |
| 575 | int ipc_log_extract(void *ctxt, char *buff, int size) |
| 576 | { |
| 577 | struct encode_context ectxt; |
| 578 | struct decode_context dctxt; |
| 579 | void (*deserialize_func)(struct encode_context *ectxt, |
| 580 | struct decode_context *dctxt); |
| 581 | struct ipc_log_context *ilctxt = (struct ipc_log_context *)ctxt; |
| 582 | unsigned long flags; |
Lynus Vaz | 802d738 | 2017-06-30 15:10:26 +0530 | [diff] [blame] | 583 | int ret; |
Karthikeyan Ramasubramanian | 44dc770 | 2016-09-16 15:39:37 -0600 | [diff] [blame] | 584 | |
| 585 | if (size < MAX_MSG_DECODED_SIZE) |
| 586 | return -EINVAL; |
| 587 | |
| 588 | dctxt.output_format = OUTPUT_DEBUGFS; |
| 589 | dctxt.buff = buff; |
| 590 | dctxt.size = size; |
| 591 | read_lock_irqsave(&context_list_lock_lha1, flags); |
| 592 | spin_lock(&ilctxt->context_lock_lhb1); |
Lynus Vaz | 802d738 | 2017-06-30 15:10:26 +0530 | [diff] [blame] | 593 | if (ilctxt->destroyed) { |
| 594 | ret = -EIO; |
| 595 | goto done; |
| 596 | } |
| 597 | |
Karthikeyan Ramasubramanian | 44dc770 | 2016-09-16 15:39:37 -0600 | [diff] [blame] | 598 | while (dctxt.size >= MAX_MSG_DECODED_SIZE && |
| 599 | !is_nd_read_empty(ilctxt)) { |
| 600 | msg_read(ilctxt, &ectxt); |
| 601 | deserialize_func = get_deserialization_func(ilctxt, |
| 602 | ectxt.hdr.type); |
| 603 | spin_unlock(&ilctxt->context_lock_lhb1); |
| 604 | read_unlock_irqrestore(&context_list_lock_lha1, flags); |
| 605 | if (deserialize_func) |
| 606 | deserialize_func(&ectxt, &dctxt); |
| 607 | else |
| 608 | pr_err("%s: unknown message 0x%x\n", |
| 609 | __func__, ectxt.hdr.type); |
| 610 | read_lock_irqsave(&context_list_lock_lha1, flags); |
| 611 | spin_lock(&ilctxt->context_lock_lhb1); |
| 612 | } |
Lynus Vaz | 802d738 | 2017-06-30 15:10:26 +0530 | [diff] [blame] | 613 | ret = size - dctxt.size; |
| 614 | if (ret == 0) { |
| 615 | if (!ilctxt->destroyed) |
| 616 | reinit_completion(&ilctxt->read_avail); |
| 617 | else |
| 618 | ret = -EIO; |
| 619 | } |
| 620 | done: |
Karthikeyan Ramasubramanian | 44dc770 | 2016-09-16 15:39:37 -0600 | [diff] [blame] | 621 | spin_unlock(&ilctxt->context_lock_lhb1); |
| 622 | read_unlock_irqrestore(&context_list_lock_lha1, flags); |
Lynus Vaz | 802d738 | 2017-06-30 15:10:26 +0530 | [diff] [blame] | 623 | return ret; |
Karthikeyan Ramasubramanian | 44dc770 | 2016-09-16 15:39:37 -0600 | [diff] [blame] | 624 | } |
| 625 | EXPORT_SYMBOL(ipc_log_extract); |
| 626 | |
| 627 | /* |
| 628 | * Helper function used to read data from a message context. |
| 629 | * |
| 630 | * @ectxt context initialized by calling msg_read() |
| 631 | * @data data to read |
| 632 | * @size number of bytes of data to read |
| 633 | */ |
| 634 | static void tsv_read_data(struct encode_context *ectxt, |
| 635 | void *data, uint32_t size) |
| 636 | { |
Kyle Yan | 74fdd73 | 2017-03-22 13:37:08 -0700 | [diff] [blame] | 637 | if (WARN_ON((ectxt->offset + size) > MAX_MSG_SIZE)) { |
| 638 | memcpy(data, (ectxt->buff + ectxt->offset), |
| 639 | MAX_MSG_SIZE - ectxt->offset - 1); |
| 640 | ectxt->offset += MAX_MSG_SIZE - ectxt->offset - 1; |
Karthikeyan Ramasubramanian | 44dc770 | 2016-09-16 15:39:37 -0600 | [diff] [blame] | 641 | return; |
Kyle Yan | 74fdd73 | 2017-03-22 13:37:08 -0700 | [diff] [blame] | 642 | } |
Karthikeyan Ramasubramanian | 44dc770 | 2016-09-16 15:39:37 -0600 | [diff] [blame] | 643 | memcpy(data, (ectxt->buff + ectxt->offset), size); |
| 644 | ectxt->offset += size; |
| 645 | } |
| 646 | |
| 647 | /* |
| 648 | * Helper function that reads a type from the context and updates the |
| 649 | * context pointers. |
| 650 | * |
| 651 | * @ectxt context initialized by calling msg_read() |
| 652 | * @hdr type header |
| 653 | */ |
| 654 | static void tsv_read_header(struct encode_context *ectxt, |
| 655 | struct tsv_header *hdr) |
| 656 | { |
Kyle Yan | 74fdd73 | 2017-03-22 13:37:08 -0700 | [diff] [blame] | 657 | if (WARN_ON((ectxt->offset + sizeof(*hdr)) > MAX_MSG_SIZE)) { |
| 658 | memcpy(hdr, (ectxt->buff + ectxt->offset), |
| 659 | MAX_MSG_SIZE - ectxt->offset - 1); |
| 660 | ectxt->offset += MAX_MSG_SIZE - ectxt->offset - 1; |
Karthikeyan Ramasubramanian | 44dc770 | 2016-09-16 15:39:37 -0600 | [diff] [blame] | 661 | return; |
Kyle Yan | 74fdd73 | 2017-03-22 13:37:08 -0700 | [diff] [blame] | 662 | } |
Karthikeyan Ramasubramanian | 44dc770 | 2016-09-16 15:39:37 -0600 | [diff] [blame] | 663 | memcpy(hdr, (ectxt->buff + ectxt->offset), sizeof(*hdr)); |
| 664 | ectxt->offset += sizeof(*hdr); |
| 665 | } |
| 666 | |
| 667 | /* |
| 668 | * Reads a timestamp. |
| 669 | * |
| 670 | * @ectxt context initialized by calling msg_read() |
| 671 | * @dctxt deserialization context |
| 672 | * @format output format (appended to %6u.09u timestamp format) |
| 673 | */ |
| 674 | void tsv_timestamp_read(struct encode_context *ectxt, |
| 675 | struct decode_context *dctxt, const char *format) |
| 676 | { |
| 677 | struct tsv_header hdr; |
| 678 | uint64_t val; |
| 679 | unsigned long nanosec_rem; |
| 680 | |
| 681 | tsv_read_header(ectxt, &hdr); |
| 682 | if (WARN_ON(hdr.type != TSV_TYPE_TIMESTAMP)) |
| 683 | return; |
| 684 | tsv_read_data(ectxt, &val, sizeof(val)); |
| 685 | nanosec_rem = do_div(val, 1000000000U); |
| 686 | IPC_SPRINTF_DECODE(dctxt, "[%6u.%09lu%s/", |
| 687 | (unsigned int)val, nanosec_rem, format); |
| 688 | } |
| 689 | EXPORT_SYMBOL(tsv_timestamp_read); |
| 690 | |
| 691 | /* |
| 692 | * Reads a QTimer timestamp. |
| 693 | * |
| 694 | * @ectxt context initialized by calling msg_read() |
| 695 | * @dctxt deserialization context |
| 696 | * @format output format (appended to %#18llx timestamp format) |
| 697 | */ |
| 698 | void tsv_qtimer_read(struct encode_context *ectxt, |
| 699 | struct decode_context *dctxt, const char *format) |
| 700 | { |
| 701 | struct tsv_header hdr; |
| 702 | uint64_t val; |
| 703 | |
| 704 | tsv_read_header(ectxt, &hdr); |
| 705 | if (WARN_ON(hdr.type != TSV_TYPE_QTIMER)) |
| 706 | return; |
| 707 | tsv_read_data(ectxt, &val, sizeof(val)); |
| 708 | |
| 709 | /* |
| 710 | * This gives 16 hex digits of output. The # prefix prepends |
| 711 | * a 0x, and these characters count as part of the number. |
| 712 | */ |
| 713 | IPC_SPRINTF_DECODE(dctxt, "%#18llx]%s", val, format); |
| 714 | } |
| 715 | EXPORT_SYMBOL(tsv_qtimer_read); |
| 716 | |
| 717 | /* |
| 718 | * Reads a data pointer. |
| 719 | * |
| 720 | * @ectxt context initialized by calling msg_read() |
| 721 | * @dctxt deserialization context |
| 722 | * @format output format |
| 723 | */ |
| 724 | void tsv_pointer_read(struct encode_context *ectxt, |
| 725 | struct decode_context *dctxt, const char *format) |
| 726 | { |
| 727 | struct tsv_header hdr; |
| 728 | void *val; |
| 729 | |
| 730 | tsv_read_header(ectxt, &hdr); |
| 731 | if (WARN_ON(hdr.type != TSV_TYPE_POINTER)) |
| 732 | return; |
| 733 | tsv_read_data(ectxt, &val, sizeof(val)); |
| 734 | |
| 735 | IPC_SPRINTF_DECODE(dctxt, format, val); |
| 736 | } |
| 737 | EXPORT_SYMBOL(tsv_pointer_read); |
| 738 | |
| 739 | /* |
| 740 | * Reads a 32-bit integer value. |
| 741 | * |
| 742 | * @ectxt context initialized by calling msg_read() |
| 743 | * @dctxt deserialization context |
| 744 | * @format output format |
| 745 | */ |
| 746 | int32_t tsv_int32_read(struct encode_context *ectxt, |
| 747 | struct decode_context *dctxt, const char *format) |
| 748 | { |
| 749 | struct tsv_header hdr; |
| 750 | int32_t val; |
| 751 | |
| 752 | tsv_read_header(ectxt, &hdr); |
| 753 | if (WARN_ON(hdr.type != TSV_TYPE_INT32)) |
| 754 | return -EINVAL; |
| 755 | tsv_read_data(ectxt, &val, sizeof(val)); |
| 756 | |
| 757 | IPC_SPRINTF_DECODE(dctxt, format, val); |
| 758 | return val; |
| 759 | } |
| 760 | EXPORT_SYMBOL(tsv_int32_read); |
| 761 | |
| 762 | /* |
| 763 | * Reads a byte array/string. |
| 764 | * |
| 765 | * @ectxt context initialized by calling msg_read() |
| 766 | * @dctxt deserialization context |
| 767 | * @format output format |
| 768 | */ |
| 769 | void tsv_byte_array_read(struct encode_context *ectxt, |
| 770 | struct decode_context *dctxt, const char *format) |
| 771 | { |
| 772 | struct tsv_header hdr; |
| 773 | |
| 774 | tsv_read_header(ectxt, &hdr); |
| 775 | if (WARN_ON(hdr.type != TSV_TYPE_BYTE_ARRAY)) |
| 776 | return; |
| 777 | tsv_read_data(ectxt, dctxt->buff, hdr.size); |
| 778 | dctxt->buff += hdr.size; |
| 779 | dctxt->size -= hdr.size; |
| 780 | } |
| 781 | EXPORT_SYMBOL(tsv_byte_array_read); |
| 782 | |
| 783 | int add_deserialization_func(void *ctxt, int type, |
| 784 | void (*dfunc)(struct encode_context *, |
| 785 | struct decode_context *)) |
| 786 | { |
| 787 | struct ipc_log_context *ilctxt = (struct ipc_log_context *)ctxt; |
| 788 | struct dfunc_info *df_info; |
| 789 | unsigned long flags; |
| 790 | |
| 791 | if (!ilctxt || !dfunc) |
| 792 | return -EINVAL; |
| 793 | |
| 794 | df_info = kmalloc(sizeof(struct dfunc_info), GFP_KERNEL); |
| 795 | if (!df_info) |
| 796 | return -ENOSPC; |
| 797 | |
| 798 | read_lock_irqsave(&context_list_lock_lha1, flags); |
| 799 | spin_lock(&ilctxt->context_lock_lhb1); |
| 800 | df_info->type = type; |
| 801 | df_info->dfunc = dfunc; |
| 802 | list_add_tail(&df_info->list, &ilctxt->dfunc_info_list); |
| 803 | spin_unlock(&ilctxt->context_lock_lhb1); |
| 804 | read_unlock_irqrestore(&context_list_lock_lha1, flags); |
| 805 | return 0; |
| 806 | } |
| 807 | EXPORT_SYMBOL(add_deserialization_func); |
| 808 | |
| 809 | static void *get_deserialization_func(struct ipc_log_context *ilctxt, |
| 810 | int type) |
| 811 | { |
| 812 | struct dfunc_info *df_info = NULL; |
| 813 | |
| 814 | if (!ilctxt) |
| 815 | return NULL; |
| 816 | |
| 817 | list_for_each_entry(df_info, &ilctxt->dfunc_info_list, list) { |
| 818 | if (df_info->type == type) |
| 819 | return df_info->dfunc; |
| 820 | } |
| 821 | return NULL; |
| 822 | } |
| 823 | |
| 824 | /** |
| 825 | * ipc_log_context_create: Create a debug log context |
| 826 | * Should not be called from atomic context |
| 827 | * |
| 828 | * @max_num_pages: Number of pages of logging space required (max. 10) |
| 829 | * @mod_name : Name of the directory entry under DEBUGFS |
| 830 | * @user_version : Version number of user-defined message formats |
| 831 | * |
| 832 | * returns context id on success, NULL on failure |
| 833 | */ |
| 834 | void *ipc_log_context_create(int max_num_pages, |
| 835 | const char *mod_name, uint16_t user_version) |
| 836 | { |
| 837 | struct ipc_log_context *ctxt; |
| 838 | struct ipc_log_page *pg = NULL; |
| 839 | int page_cnt; |
| 840 | unsigned long flags; |
| 841 | |
| 842 | ctxt = kzalloc(sizeof(struct ipc_log_context), GFP_KERNEL); |
| 843 | if (!ctxt) |
| 844 | return 0; |
| 845 | |
| 846 | init_completion(&ctxt->read_avail); |
| 847 | INIT_LIST_HEAD(&ctxt->page_list); |
| 848 | INIT_LIST_HEAD(&ctxt->dfunc_info_list); |
| 849 | spin_lock_init(&ctxt->context_lock_lhb1); |
| 850 | for (page_cnt = 0; page_cnt < max_num_pages; page_cnt++) { |
| 851 | pg = kzalloc(sizeof(struct ipc_log_page), GFP_KERNEL); |
| 852 | if (!pg) { |
| 853 | pr_err("%s: cannot create ipc_log_page\n", __func__); |
| 854 | goto release_ipc_log_context; |
| 855 | } |
| 856 | pg->hdr.log_id = (uint64_t)(uintptr_t)ctxt; |
| 857 | pg->hdr.page_num = LOG_PAGE_FLAG | page_cnt; |
| 858 | pg->hdr.ctx_offset = (int64_t)((uint64_t)(uintptr_t)ctxt - |
| 859 | (uint64_t)(uintptr_t)&pg->hdr); |
| 860 | |
| 861 | /* set magic last to signal that page init is complete */ |
| 862 | pg->hdr.magic = IPC_LOGGING_MAGIC_NUM; |
| 863 | pg->hdr.nmagic = ~(IPC_LOGGING_MAGIC_NUM); |
| 864 | |
| 865 | spin_lock_irqsave(&ctxt->context_lock_lhb1, flags); |
| 866 | list_add_tail(&pg->hdr.list, &ctxt->page_list); |
| 867 | spin_unlock_irqrestore(&ctxt->context_lock_lhb1, flags); |
| 868 | } |
| 869 | |
| 870 | ctxt->log_id = (uint64_t)(uintptr_t)ctxt; |
| 871 | ctxt->version = IPC_LOG_VERSION; |
| 872 | strlcpy(ctxt->name, mod_name, IPC_LOG_MAX_CONTEXT_NAME_LEN); |
| 873 | ctxt->user_version = user_version; |
| 874 | ctxt->first_page = get_first_page(ctxt); |
| 875 | ctxt->last_page = pg; |
| 876 | ctxt->write_page = ctxt->first_page; |
| 877 | ctxt->read_page = ctxt->first_page; |
| 878 | ctxt->nd_read_page = ctxt->first_page; |
| 879 | ctxt->write_avail = max_num_pages * LOG_PAGE_DATA_SIZE; |
| 880 | ctxt->header_size = sizeof(struct ipc_log_page_header); |
Lynus Vaz | 802d738 | 2017-06-30 15:10:26 +0530 | [diff] [blame] | 881 | kref_init(&ctxt->refcount); |
| 882 | ctxt->destroyed = false; |
Karthikeyan Ramasubramanian | 44dc770 | 2016-09-16 15:39:37 -0600 | [diff] [blame] | 883 | create_ctx_debugfs(ctxt, mod_name); |
| 884 | |
| 885 | /* set magic last to signal context init is complete */ |
| 886 | ctxt->magic = IPC_LOG_CONTEXT_MAGIC_NUM; |
| 887 | ctxt->nmagic = ~(IPC_LOG_CONTEXT_MAGIC_NUM); |
| 888 | |
| 889 | write_lock_irqsave(&context_list_lock_lha1, flags); |
| 890 | list_add_tail(&ctxt->list, &ipc_log_context_list); |
| 891 | write_unlock_irqrestore(&context_list_lock_lha1, flags); |
| 892 | return (void *)ctxt; |
| 893 | |
| 894 | release_ipc_log_context: |
| 895 | while (page_cnt-- > 0) { |
| 896 | pg = get_first_page(ctxt); |
| 897 | list_del(&pg->hdr.list); |
| 898 | kfree(pg); |
| 899 | } |
| 900 | kfree(ctxt); |
| 901 | return 0; |
| 902 | } |
| 903 | EXPORT_SYMBOL(ipc_log_context_create); |
| 904 | |
Lynus Vaz | 802d738 | 2017-06-30 15:10:26 +0530 | [diff] [blame] | 905 | void ipc_log_context_free(struct kref *kref) |
| 906 | { |
| 907 | struct ipc_log_context *ilctxt = container_of(kref, |
| 908 | struct ipc_log_context, refcount); |
| 909 | struct ipc_log_page *pg = NULL; |
| 910 | |
| 911 | while (!list_empty(&ilctxt->page_list)) { |
| 912 | pg = get_first_page(ilctxt); |
| 913 | list_del(&pg->hdr.list); |
| 914 | kfree(pg); |
| 915 | } |
| 916 | |
| 917 | kfree(ilctxt); |
| 918 | } |
| 919 | |
Karthikeyan Ramasubramanian | 44dc770 | 2016-09-16 15:39:37 -0600 | [diff] [blame] | 920 | /* |
| 921 | * Destroy debug log context |
| 922 | * |
| 923 | * @ctxt: debug log context created by calling ipc_log_context_create API. |
| 924 | */ |
| 925 | int ipc_log_context_destroy(void *ctxt) |
| 926 | { |
| 927 | struct ipc_log_context *ilctxt = (struct ipc_log_context *)ctxt; |
Arun Kumar Neelakantam | 2f1fbe4 | 2018-09-21 15:19:09 +0530 | [diff] [blame] | 928 | struct dfunc_info *df_info = NULL, *tmp = NULL; |
Karthikeyan Ramasubramanian | 44dc770 | 2016-09-16 15:39:37 -0600 | [diff] [blame] | 929 | unsigned long flags; |
| 930 | |
| 931 | if (!ilctxt) |
| 932 | return 0; |
| 933 | |
Lynus Vaz | 802d738 | 2017-06-30 15:10:26 +0530 | [diff] [blame] | 934 | debugfs_remove_recursive(ilctxt->dent); |
| 935 | |
| 936 | spin_lock(&ilctxt->context_lock_lhb1); |
| 937 | ilctxt->destroyed = true; |
| 938 | complete_all(&ilctxt->read_avail); |
Arun Kumar Neelakantam | 2f1fbe4 | 2018-09-21 15:19:09 +0530 | [diff] [blame] | 939 | list_for_each_entry_safe(df_info, tmp, &ilctxt->dfunc_info_list, list) { |
| 940 | list_del(&df_info->list); |
| 941 | kfree(df_info); |
| 942 | } |
Lynus Vaz | 802d738 | 2017-06-30 15:10:26 +0530 | [diff] [blame] | 943 | spin_unlock(&ilctxt->context_lock_lhb1); |
Karthikeyan Ramasubramanian | 44dc770 | 2016-09-16 15:39:37 -0600 | [diff] [blame] | 944 | |
| 945 | write_lock_irqsave(&context_list_lock_lha1, flags); |
| 946 | list_del(&ilctxt->list); |
| 947 | write_unlock_irqrestore(&context_list_lock_lha1, flags); |
| 948 | |
Lynus Vaz | 802d738 | 2017-06-30 15:10:26 +0530 | [diff] [blame] | 949 | ipc_log_context_put(ilctxt); |
Karthikeyan Ramasubramanian | 44dc770 | 2016-09-16 15:39:37 -0600 | [diff] [blame] | 950 | |
Karthikeyan Ramasubramanian | 44dc770 | 2016-09-16 15:39:37 -0600 | [diff] [blame] | 951 | return 0; |
| 952 | } |
| 953 | EXPORT_SYMBOL(ipc_log_context_destroy); |
| 954 | |
| 955 | static int __init ipc_logging_init(void) |
| 956 | { |
| 957 | check_and_create_debugfs(); |
| 958 | return 0; |
| 959 | } |
| 960 | |
| 961 | module_init(ipc_logging_init); |
| 962 | |
| 963 | MODULE_DESCRIPTION("ipc logging"); |
| 964 | MODULE_LICENSE("GPL v2"); |