| 1 | /* |
| 2 | * LTTng serializing code. |
| 3 | * |
| 4 | * Copyright Mathieu Desnoyers, March 2007. |
| 5 | * |
| 6 | * Licensed under the GPLv2. |
| 7 | * |
| 8 | * See this discussion about weirdness about passing va_list and then va_list to |
| 9 | * functions. (related to array argument passing). va_list seems to be |
| 10 | * implemented as an array on x86_64, but not on i386... This is why we pass a |
| 11 | * va_list * to ltt_vtrace. |
| 12 | */ |
| 13 | |
| 14 | #include <stdarg.h> |
| 15 | //ust// #include <linux/ctype.h> |
| 16 | //ust// #include <linux/string.h> |
| 17 | //ust// #include <linux/module.h> |
| 18 | //ust// #include <linux/ltt-tracer.h> |
| 19 | #include <string.h> |
| 20 | #include <stdint.h> |
| 21 | #include "kernelcompat.h" |
| 22 | #include "relay.h" |
| 23 | #include "tracer.h" |
| 24 | #include "list.h" |
| 25 | #include "usterr.h" |
| 26 | |
| 27 | enum ltt_type { |
| 28 | LTT_TYPE_SIGNED_INT, |
| 29 | LTT_TYPE_UNSIGNED_INT, |
| 30 | LTT_TYPE_STRING, |
| 31 | LTT_TYPE_NONE, |
| 32 | }; |
| 33 | |
| 34 | #define LTT_ATTRIBUTE_NETWORK_BYTE_ORDER (1<<1) |
| 35 | |
| 36 | /* |
| 37 | * Inspired from vsnprintf |
| 38 | * |
| 39 | * The serialization format string supports the basic printf format strings. |
| 40 | * In addition, it defines new formats that can be used to serialize more |
| 41 | * complex/non portable data structures. |
| 42 | * |
| 43 | * Typical use: |
| 44 | * |
| 45 | * field_name %ctype |
| 46 | * field_name #tracetype %ctype |
| 47 | * field_name #tracetype %ctype1 %ctype2 ... |
| 48 | * |
| 49 | * A conversion is performed between format string types supported by GCC and |
| 50 | * the trace type requested. GCC type is used to perform type checking on format |
| 51 | * strings. Trace type is used to specify the exact binary representation |
| 52 | * in the trace. A mapping is done between one or more GCC types to one trace |
| 53 | * type. Sign extension, if required by the conversion, is performed following |
| 54 | * the trace type. |
| 55 | * |
| 56 | * If a gcc format is not declared with a trace format, the gcc format is |
| 57 | * also used as binary representation in the trace. |
| 58 | * |
| 59 | * Strings are supported with %s. |
| 60 | * A single tracetype (sequence) can take multiple c types as parameter. |
| 61 | * |
| 62 | * c types: |
| 63 | * |
| 64 | * see printf(3). |
| 65 | * |
| 66 | * Note: to write a uint32_t in a trace, the following expression is recommended |
| 67 | * si it can be portable: |
| 68 | * |
| 69 | * ("#4u%lu", (unsigned long)var) |
| 70 | * |
| 71 | * trace types: |
| 72 | * |
| 73 | * Serialization specific formats : |
| 74 | * |
| 75 | * Fixed size integers |
| 76 | * #1u writes uint8_t |
| 77 | * #2u writes uint16_t |
| 78 | * #4u writes uint32_t |
| 79 | * #8u writes uint64_t |
| 80 | * #1d writes int8_t |
| 81 | * #2d writes int16_t |
| 82 | * #4d writes int32_t |
| 83 | * #8d writes int64_t |
| 84 | * i.e.: |
| 85 | * #1u%lu #2u%lu #4d%lu #8d%lu #llu%hu #d%lu |
| 86 | * |
| 87 | * * Attributes: |
| 88 | * |
| 89 | * n: (for network byte order) |
| 90 | * #ntracetype%ctype |
| 91 | * is written in the trace in network byte order. |
| 92 | * |
| 93 | * i.e.: #bn4u%lu, #n%lu, #b%u |
| 94 | * |
| 95 | * TODO (eventually) |
| 96 | * Variable length sequence |
| 97 | * #a #tracetype1 #tracetype2 %array_ptr %elem_size %num_elems |
| 98 | * In the trace: |
| 99 | * #a specifies that this is a sequence |
| 100 | * #tracetype1 is the type of elements in the sequence |
| 101 | * #tracetype2 is the type of the element count |
| 102 | * GCC input: |
| 103 | * array_ptr is a pointer to an array that contains members of size |
| 104 | * elem_size. |
| 105 | * num_elems is the number of elements in the array. |
| 106 | * i.e.: #a #lu #lu %p %lu %u |
| 107 | * |
| 108 | * Callback |
| 109 | * #k callback (taken from the probe data) |
| 110 | * The following % arguments are exepected by the callback |
| 111 | * |
| 112 | * i.e.: #a #lu #lu #k %p |
| 113 | * |
| 114 | * Note: No conversion is done from floats to integers, nor from integers to |
| 115 | * floats between c types and trace types. float conversion from double to float |
| 116 | * or from float to double is also not supported. |
| 117 | * |
| 118 | * REMOVE |
| 119 | * %*b expects sizeof(data), data |
| 120 | * where sizeof(data) is 1, 2, 4 or 8 |
| 121 | * |
| 122 | * Fixed length struct, union or array. |
| 123 | * FIXME: unable to extract those sizes statically. |
| 124 | * %*r expects sizeof(*ptr), ptr |
| 125 | * %*.*r expects sizeof(*ptr), __alignof__(*ptr), ptr |
| 126 | * struct and unions removed. |
| 127 | * Fixed length array: |
| 128 | * [%p]#a[len #tracetype] |
| 129 | * i.e.: [%p]#a[12 #lu] |
| 130 | * |
| 131 | * Variable length sequence |
| 132 | * %*.*:*v expects sizeof(*ptr), __alignof__(*ptr), elem_num, ptr |
| 133 | * where elem_num is the number of elements in the sequence |
| 134 | */ |
| 135 | static inline const char *parse_trace_type(const char *fmt, |
| 136 | char *trace_size, enum ltt_type *trace_type, |
| 137 | unsigned long *attributes) |
| 138 | { |
| 139 | int qualifier; /* 'h', 'l', or 'L' for integer fields */ |
| 140 | /* 'z' support added 23/7/1999 S.H. */ |
| 141 | /* 'z' changed to 'Z' --davidm 1/25/99 */ |
| 142 | /* 't' added for ptrdiff_t */ |
| 143 | |
| 144 | /* parse attributes. */ |
| 145 | repeat: |
| 146 | switch (*fmt) { |
| 147 | case 'n': |
| 148 | *attributes |= LTT_ATTRIBUTE_NETWORK_BYTE_ORDER; |
| 149 | ++fmt; |
| 150 | goto repeat; |
| 151 | } |
| 152 | |
| 153 | /* get the conversion qualifier */ |
| 154 | qualifier = -1; |
| 155 | if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' || |
| 156 | *fmt == 'Z' || *fmt == 'z' || *fmt == 't' || |
| 157 | *fmt == 'S' || *fmt == '1' || *fmt == '2' || |
| 158 | *fmt == '4' || *fmt == 8) { |
| 159 | qualifier = *fmt; |
| 160 | ++fmt; |
| 161 | if (qualifier == 'l' && *fmt == 'l') { |
| 162 | qualifier = 'L'; |
| 163 | ++fmt; |
| 164 | } |
| 165 | } |
| 166 | |
| 167 | switch (*fmt) { |
| 168 | case 'c': |
| 169 | *trace_type = LTT_TYPE_UNSIGNED_INT; |
| 170 | *trace_size = sizeof(unsigned char); |
| 171 | goto parse_end; |
| 172 | case 's': |
| 173 | *trace_type = LTT_TYPE_STRING; |
| 174 | goto parse_end; |
| 175 | case 'p': |
| 176 | *trace_type = LTT_TYPE_UNSIGNED_INT; |
| 177 | *trace_size = sizeof(void *); |
| 178 | goto parse_end; |
| 179 | case 'd': |
| 180 | case 'i': |
| 181 | *trace_type = LTT_TYPE_SIGNED_INT; |
| 182 | break; |
| 183 | case 'o': |
| 184 | case 'u': |
| 185 | case 'x': |
| 186 | case 'X': |
| 187 | *trace_type = LTT_TYPE_UNSIGNED_INT; |
| 188 | break; |
| 189 | default: |
| 190 | if (!*fmt) |
| 191 | --fmt; |
| 192 | goto parse_end; |
| 193 | } |
| 194 | switch (qualifier) { |
| 195 | case 'L': |
| 196 | *trace_size = sizeof(long long); |
| 197 | break; |
| 198 | case 'l': |
| 199 | *trace_size = sizeof(long); |
| 200 | break; |
| 201 | case 'Z': |
| 202 | case 'z': |
| 203 | *trace_size = sizeof(size_t); |
| 204 | break; |
| 205 | //ust// case 't': |
| 206 | //ust// *trace_size = sizeof(ptrdiff_t); |
| 207 | //ust// break; |
| 208 | case 'h': |
| 209 | *trace_size = sizeof(short); |
| 210 | break; |
| 211 | case '1': |
| 212 | *trace_size = sizeof(uint8_t); |
| 213 | break; |
| 214 | case '2': |
| 215 | *trace_size = sizeof(uint16_t); |
| 216 | break; |
| 217 | case '4': |
| 218 | *trace_size = sizeof(uint32_t); |
| 219 | break; |
| 220 | case '8': |
| 221 | *trace_size = sizeof(uint64_t); |
| 222 | break; |
| 223 | default: |
| 224 | *trace_size = sizeof(int); |
| 225 | } |
| 226 | |
| 227 | parse_end: |
| 228 | return fmt; |
| 229 | } |
| 230 | |
| 231 | /* |
| 232 | * Restrictions: |
| 233 | * Field width and precision are *not* supported. |
| 234 | * %n not supported. |
| 235 | */ |
| 236 | static inline const char *parse_c_type(const char *fmt, |
| 237 | char *c_size, enum ltt_type *c_type) |
| 238 | { |
| 239 | int qualifier; /* 'h', 'l', or 'L' for integer fields */ |
| 240 | /* 'z' support added 23/7/1999 S.H. */ |
| 241 | /* 'z' changed to 'Z' --davidm 1/25/99 */ |
| 242 | /* 't' added for ptrdiff_t */ |
| 243 | |
| 244 | /* process flags : ignore standard print formats for now. */ |
| 245 | repeat: |
| 246 | switch (*fmt) { |
| 247 | case '-': |
| 248 | case '+': |
| 249 | case ' ': |
| 250 | case '#': |
| 251 | case '0': |
| 252 | ++fmt; |
| 253 | goto repeat; |
| 254 | } |
| 255 | |
| 256 | /* get the conversion qualifier */ |
| 257 | qualifier = -1; |
| 258 | if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' || |
| 259 | *fmt == 'Z' || *fmt == 'z' || *fmt == 't' || |
| 260 | *fmt == 'S') { |
| 261 | qualifier = *fmt; |
| 262 | ++fmt; |
| 263 | if (qualifier == 'l' && *fmt == 'l') { |
| 264 | qualifier = 'L'; |
| 265 | ++fmt; |
| 266 | } |
| 267 | } |
| 268 | |
| 269 | switch (*fmt) { |
| 270 | case 'c': |
| 271 | *c_type = LTT_TYPE_UNSIGNED_INT; |
| 272 | *c_size = sizeof(unsigned char); |
| 273 | goto parse_end; |
| 274 | case 's': |
| 275 | *c_type = LTT_TYPE_STRING; |
| 276 | goto parse_end; |
| 277 | case 'p': |
| 278 | *c_type = LTT_TYPE_UNSIGNED_INT; |
| 279 | *c_size = sizeof(void *); |
| 280 | goto parse_end; |
| 281 | case 'd': |
| 282 | case 'i': |
| 283 | *c_type = LTT_TYPE_SIGNED_INT; |
| 284 | break; |
| 285 | case 'o': |
| 286 | case 'u': |
| 287 | case 'x': |
| 288 | case 'X': |
| 289 | *c_type = LTT_TYPE_UNSIGNED_INT; |
| 290 | break; |
| 291 | default: |
| 292 | if (!*fmt) |
| 293 | --fmt; |
| 294 | goto parse_end; |
| 295 | } |
| 296 | switch (qualifier) { |
| 297 | case 'L': |
| 298 | *c_size = sizeof(long long); |
| 299 | break; |
| 300 | case 'l': |
| 301 | *c_size = sizeof(long); |
| 302 | break; |
| 303 | case 'Z': |
| 304 | case 'z': |
| 305 | *c_size = sizeof(size_t); |
| 306 | break; |
| 307 | //ust// case 't': |
| 308 | //ust// *c_size = sizeof(ptrdiff_t); |
| 309 | //ust// break; |
| 310 | case 'h': |
| 311 | *c_size = sizeof(short); |
| 312 | break; |
| 313 | default: |
| 314 | *c_size = sizeof(int); |
| 315 | } |
| 316 | |
| 317 | parse_end: |
| 318 | return fmt; |
| 319 | } |
| 320 | |
| 321 | static inline size_t serialize_trace_data(struct rchan_buf *buf, |
| 322 | size_t buf_offset, |
| 323 | char trace_size, enum ltt_type trace_type, |
| 324 | char c_size, enum ltt_type c_type, |
| 325 | int *largest_align, va_list *args) |
| 326 | { |
| 327 | union { |
| 328 | unsigned long v_ulong; |
| 329 | uint64_t v_uint64; |
| 330 | struct { |
| 331 | const char *s; |
| 332 | size_t len; |
| 333 | } v_string; |
| 334 | } tmp; |
| 335 | |
| 336 | /* |
| 337 | * Be careful about sign extension here. |
| 338 | * Sign extension is done with the destination (trace) type. |
| 339 | */ |
| 340 | switch (trace_type) { |
| 341 | case LTT_TYPE_SIGNED_INT: |
| 342 | switch (c_size) { |
| 343 | case 1: |
| 344 | tmp.v_ulong = (long)(int8_t)va_arg(*args, int); |
| 345 | break; |
| 346 | case 2: |
| 347 | tmp.v_ulong = (long)(int16_t)va_arg(*args, int); |
| 348 | break; |
| 349 | case 4: |
| 350 | tmp.v_ulong = (long)(int32_t)va_arg(*args, int); |
| 351 | break; |
| 352 | case 8: |
| 353 | tmp.v_uint64 = va_arg(*args, int64_t); |
| 354 | break; |
| 355 | default: |
| 356 | BUG(); |
| 357 | } |
| 358 | break; |
| 359 | case LTT_TYPE_UNSIGNED_INT: |
| 360 | switch (c_size) { |
| 361 | case 1: |
| 362 | tmp.v_ulong = (unsigned long)(uint8_t) |
| 363 | va_arg(*args, unsigned int); |
| 364 | break; |
| 365 | case 2: |
| 366 | tmp.v_ulong = (unsigned long)(uint16_t) |
| 367 | va_arg(*args, unsigned int); |
| 368 | break; |
| 369 | case 4: |
| 370 | tmp.v_ulong = (unsigned long)(uint32_t) |
| 371 | va_arg(*args, unsigned int); |
| 372 | break; |
| 373 | case 8: |
| 374 | tmp.v_uint64 = va_arg(*args, uint64_t); |
| 375 | break; |
| 376 | default: |
| 377 | BUG(); |
| 378 | } |
| 379 | break; |
| 380 | case LTT_TYPE_STRING: |
| 381 | tmp.v_string.s = va_arg(*args, const char *); |
| 382 | if ((unsigned long)tmp.v_string.s < PAGE_SIZE) |
| 383 | tmp.v_string.s = "<NULL>"; |
| 384 | tmp.v_string.len = strlen(tmp.v_string.s)+1; |
| 385 | if (buf) |
| 386 | ltt_relay_write(buf, buf_offset, tmp.v_string.s, |
| 387 | tmp.v_string.len); |
| 388 | buf_offset += tmp.v_string.len; |
| 389 | goto copydone; |
| 390 | default: |
| 391 | BUG(); |
| 392 | } |
| 393 | |
| 394 | /* |
| 395 | * If trace_size is lower or equal to 4 bytes, there is no sign |
| 396 | * extension to do because we are already encoded in a long. Therefore, |
| 397 | * we can combine signed and unsigned ops. 4 bytes float also works |
| 398 | * with this, because we do a simple copy of 4 bytes into 4 bytes |
| 399 | * without manipulation (and we do not support conversion from integers |
| 400 | * to floats). |
| 401 | * It is also the case if c_size is 8 bytes, which is the largest |
| 402 | * possible integer. |
| 403 | */ |
| 404 | if (ltt_get_alignment()) { |
| 405 | buf_offset += ltt_align(buf_offset, trace_size); |
| 406 | if (largest_align) |
| 407 | *largest_align = max_t(int, *largest_align, trace_size); |
| 408 | } |
| 409 | if (trace_size <= 4 || c_size == 8) { |
| 410 | if (buf) { |
| 411 | switch (trace_size) { |
| 412 | case 1: |
| 413 | if (c_size == 8) |
| 414 | ltt_relay_write(buf, buf_offset, |
| 415 | (uint8_t[]){ (uint8_t)tmp.v_uint64 }, |
| 416 | sizeof(uint8_t)); |
| 417 | else |
| 418 | ltt_relay_write(buf, buf_offset, |
| 419 | (uint8_t[]){ (uint8_t)tmp.v_ulong }, |
| 420 | sizeof(uint8_t)); |
| 421 | break; |
| 422 | case 2: |
| 423 | if (c_size == 8) |
| 424 | ltt_relay_write(buf, buf_offset, |
| 425 | (uint16_t[]){ (uint16_t)tmp.v_uint64 }, |
| 426 | sizeof(uint16_t)); |
| 427 | else |
| 428 | ltt_relay_write(buf, buf_offset, |
| 429 | (uint16_t[]){ (uint16_t)tmp.v_ulong }, |
| 430 | sizeof(uint16_t)); |
| 431 | break; |
| 432 | case 4: |
| 433 | if (c_size == 8) |
| 434 | ltt_relay_write(buf, buf_offset, |
| 435 | (uint32_t[]){ (uint32_t)tmp.v_uint64 }, |
| 436 | sizeof(uint32_t)); |
| 437 | else |
| 438 | ltt_relay_write(buf, buf_offset, |
| 439 | (uint32_t[]){ (uint32_t)tmp.v_ulong }, |
| 440 | sizeof(uint32_t)); |
| 441 | break; |
| 442 | case 8: |
| 443 | /* |
| 444 | * c_size cannot be other than 8 here because |
| 445 | * trace_size > 4. |
| 446 | */ |
| 447 | ltt_relay_write(buf, buf_offset, |
| 448 | (uint64_t[]){ (uint64_t)tmp.v_uint64 }, |
| 449 | sizeof(uint64_t)); |
| 450 | break; |
| 451 | default: |
| 452 | BUG(); |
| 453 | } |
| 454 | } |
| 455 | buf_offset += trace_size; |
| 456 | goto copydone; |
| 457 | } else { |
| 458 | /* |
| 459 | * Perform sign extension. |
| 460 | */ |
| 461 | if (buf) { |
| 462 | switch (trace_type) { |
| 463 | case LTT_TYPE_SIGNED_INT: |
| 464 | ltt_relay_write(buf, buf_offset, |
| 465 | (int64_t[]){ (int64_t)tmp.v_ulong }, |
| 466 | sizeof(int64_t)); |
| 467 | break; |
| 468 | case LTT_TYPE_UNSIGNED_INT: |
| 469 | ltt_relay_write(buf, buf_offset, |
| 470 | (uint64_t[]){ (uint64_t)tmp.v_ulong }, |
| 471 | sizeof(uint64_t)); |
| 472 | break; |
| 473 | default: |
| 474 | BUG(); |
| 475 | } |
| 476 | } |
| 477 | buf_offset += trace_size; |
| 478 | goto copydone; |
| 479 | } |
| 480 | |
| 481 | copydone: |
| 482 | return buf_offset; |
| 483 | } |
| 484 | |
| 485 | notrace size_t ltt_serialize_data(struct rchan_buf *buf, size_t buf_offset, |
| 486 | struct ltt_serialize_closure *closure, |
| 487 | void *serialize_private, int *largest_align, |
| 488 | const char *fmt, va_list *args) |
| 489 | { |
| 490 | char trace_size = 0, c_size = 0; /* |
| 491 | * 0 (unset), 1, 2, 4, 8 bytes. |
| 492 | */ |
| 493 | enum ltt_type trace_type = LTT_TYPE_NONE, c_type = LTT_TYPE_NONE; |
| 494 | unsigned long attributes = 0; |
| 495 | |
| 496 | for (; *fmt ; ++fmt) { |
| 497 | switch (*fmt) { |
| 498 | case '#': |
| 499 | /* tracetypes (#) */ |
| 500 | ++fmt; /* skip first '#' */ |
| 501 | if (*fmt == '#') /* Escaped ## */ |
| 502 | break; |
| 503 | attributes = 0; |
| 504 | fmt = parse_trace_type(fmt, &trace_size, &trace_type, |
| 505 | &attributes); |
| 506 | break; |
| 507 | case '%': |
| 508 | /* c types (%) */ |
| 509 | ++fmt; /* skip first '%' */ |
| 510 | if (*fmt == '%') /* Escaped %% */ |
| 511 | break; |
| 512 | fmt = parse_c_type(fmt, &c_size, &c_type); |
| 513 | /* |
| 514 | * Output c types if no trace types has been |
| 515 | * specified. |
| 516 | */ |
| 517 | if (!trace_size) |
| 518 | trace_size = c_size; |
| 519 | if (trace_type == LTT_TYPE_NONE) |
| 520 | trace_type = c_type; |
| 521 | if (c_type == LTT_TYPE_STRING) |
| 522 | trace_type = LTT_TYPE_STRING; |
| 523 | /* perform trace write */ |
| 524 | buf_offset = serialize_trace_data(buf, |
| 525 | buf_offset, trace_size, |
| 526 | trace_type, c_size, c_type, |
| 527 | largest_align, args); |
| 528 | trace_size = 0; |
| 529 | c_size = 0; |
| 530 | trace_type = LTT_TYPE_NONE; |
| 531 | c_size = LTT_TYPE_NONE; |
| 532 | attributes = 0; |
| 533 | break; |
| 534 | /* default is to skip the text, doing nothing */ |
| 535 | } |
| 536 | } |
| 537 | return buf_offset; |
| 538 | } |
| 539 | EXPORT_SYMBOL_GPL(ltt_serialize_data); |
| 540 | |
| 541 | /* |
| 542 | * Calculate data size |
| 543 | * Assume that the padding for alignment starts at a sizeof(void *) address. |
| 544 | */ |
| 545 | static notrace size_t ltt_get_data_size(struct ltt_serialize_closure *closure, |
| 546 | void *serialize_private, int *largest_align, |
| 547 | const char *fmt, va_list *args) |
| 548 | { |
| 549 | ltt_serialize_cb cb = closure->callbacks[0]; |
| 550 | closure->cb_idx = 0; |
| 551 | return (size_t)cb(NULL, 0, closure, serialize_private, |
| 552 | largest_align, fmt, args); |
| 553 | } |
| 554 | |
| 555 | static notrace |
| 556 | void ltt_write_event_data(struct rchan_buf *buf, size_t buf_offset, |
| 557 | struct ltt_serialize_closure *closure, |
| 558 | void *serialize_private, int largest_align, |
| 559 | const char *fmt, va_list *args) |
| 560 | { |
| 561 | ltt_serialize_cb cb = closure->callbacks[0]; |
| 562 | closure->cb_idx = 0; |
| 563 | buf_offset += ltt_align(buf_offset, largest_align); |
| 564 | cb(buf, buf_offset, closure, serialize_private, NULL, fmt, args); |
| 565 | } |
| 566 | |
| 567 | |
| 568 | notrace void ltt_vtrace(const struct marker *mdata, void *probe_data, |
| 569 | void *call_data, const char *fmt, va_list *args) |
| 570 | { |
| 571 | int largest_align, ret; |
| 572 | struct ltt_active_marker *pdata; |
| 573 | uint16_t eID; |
| 574 | size_t data_size, slot_size; |
| 575 | unsigned int chan_index; |
| 576 | struct ltt_channel_struct *channel; |
| 577 | struct ltt_trace_struct *trace, *dest_trace = NULL; |
| 578 | struct rchan_buf *buf; |
| 579 | void *transport_data; |
| 580 | u64 tsc; |
| 581 | long buf_offset; |
| 582 | va_list args_copy; |
| 583 | struct ltt_serialize_closure closure; |
| 584 | struct ltt_probe_private_data *private_data = call_data; |
| 585 | void *serialize_private = NULL; |
| 586 | int cpu; |
| 587 | unsigned int rflags; |
| 588 | |
| 589 | /* |
| 590 | * This test is useful for quickly exiting static tracing when no trace |
| 591 | * is active. We expect to have an active trace when we get here. |
| 592 | */ |
| 593 | if (unlikely(ltt_traces.num_active_traces == 0)) |
| 594 | return; |
| 595 | |
| 596 | rcu_read_lock_sched_notrace(); |
| 597 | cpu = smp_processor_id(); |
| 598 | //ust// __get_cpu_var(ltt_nesting)++; |
| 599 | ltt_nesting++; |
| 600 | |
| 601 | pdata = (struct ltt_active_marker *)probe_data; |
| 602 | eID = mdata->event_id; |
| 603 | chan_index = mdata->channel_id; |
| 604 | closure.callbacks = pdata->probe->callbacks; |
| 605 | |
| 606 | if (unlikely(private_data)) { |
| 607 | dest_trace = private_data->trace; |
| 608 | if (private_data->serializer) |
| 609 | closure.callbacks = &private_data->serializer; |
| 610 | serialize_private = private_data->serialize_private; |
| 611 | } |
| 612 | |
| 613 | va_copy(args_copy, *args); |
| 614 | /* |
| 615 | * Assumes event payload to start on largest_align alignment. |
| 616 | */ |
| 617 | largest_align = 1; /* must be non-zero for ltt_align */ |
| 618 | data_size = ltt_get_data_size(&closure, serialize_private, |
| 619 | &largest_align, fmt, &args_copy); |
| 620 | largest_align = min_t(int, largest_align, sizeof(void *)); |
| 621 | va_end(args_copy); |
| 622 | |
| 623 | /* Iterate on each trace */ |
| 624 | list_for_each_entry_rcu(trace, <t_traces.head, list) { |
| 625 | /* |
| 626 | * Expect the filter to filter out events. If we get here, |
| 627 | * we went through tracepoint activation as a first step. |
| 628 | */ |
| 629 | if (unlikely(dest_trace && trace != dest_trace)) |
| 630 | continue; |
| 631 | if (unlikely(!trace->active)) |
| 632 | continue; |
| 633 | if (unlikely(!ltt_run_filter(trace, eID))) |
| 634 | continue; |
| 635 | #ifdef CONFIG_LTT_DEBUG_EVENT_SIZE |
| 636 | rflags = LTT_RFLAG_ID_SIZE; |
| 637 | #else |
| 638 | if (unlikely(eID >= LTT_FREE_EVENTS)) |
| 639 | rflags = LTT_RFLAG_ID; |
| 640 | else |
| 641 | rflags = 0; |
| 642 | #endif |
| 643 | /* |
| 644 | * Skip channels added after trace creation. |
| 645 | */ |
| 646 | if (unlikely(chan_index >= trace->nr_channels)) |
| 647 | continue; |
| 648 | channel = &trace->channels[chan_index]; |
| 649 | if (!channel->active) |
| 650 | continue; |
| 651 | |
| 652 | /* reserve space : header and data */ |
| 653 | ret = ltt_reserve_slot(trace, channel, &transport_data, |
| 654 | data_size, &slot_size, &buf_offset, |
| 655 | &tsc, &rflags, |
| 656 | largest_align); |
| 657 | if (unlikely(ret < 0)) |
| 658 | continue; /* buffer full */ |
| 659 | |
| 660 | va_copy(args_copy, *args); |
| 661 | /* FIXME : could probably encapsulate transport better. */ |
| 662 | //ust// buf = ((struct rchan *)channel->trans_channel_data)->buf[cpu]; |
| 663 | buf = ((struct rchan *)channel->trans_channel_data)->buf; |
| 664 | /* Out-of-order write : header and data */ |
| 665 | buf_offset = ltt_write_event_header(trace, |
| 666 | channel, buf, buf_offset, |
| 667 | eID, data_size, tsc, rflags); |
| 668 | ltt_write_event_data(buf, buf_offset, &closure, |
| 669 | serialize_private, |
| 670 | largest_align, fmt, &args_copy); |
| 671 | va_end(args_copy); |
| 672 | /* Out-of-order commit */ |
| 673 | ltt_commit_slot(channel, &transport_data, buf_offset, |
| 674 | slot_size); |
| 675 | printf("just commited event at offset %d and size %d\n", buf_offset, slot_size); |
| 676 | } |
| 677 | //ust// __get_cpu_var(ltt_nesting)--; |
| 678 | ltt_nesting--; |
| 679 | rcu_read_unlock_sched_notrace(); |
| 680 | } |
| 681 | EXPORT_SYMBOL_GPL(ltt_vtrace); |
| 682 | |
| 683 | notrace void ltt_trace(const struct marker *mdata, void *probe_data, |
| 684 | void *call_data, const char *fmt, ...) |
| 685 | { |
| 686 | va_list args; |
| 687 | |
| 688 | va_start(args, fmt); |
| 689 | ltt_vtrace(mdata, probe_data, call_data, fmt, &args); |
| 690 | va_end(args); |
| 691 | } |
| 692 | EXPORT_SYMBOL_GPL(ltt_trace); |
| 693 | |
| 694 | //ust// MODULE_LICENSE("GPL"); |
| 695 | //ust// MODULE_AUTHOR("Mathieu Desnoyers"); |
| 696 | //ust// MODULE_DESCRIPTION("Linux Trace Toolkit Next Generation Serializer"); |