1 /* SPDX-License-Identifier: BSD-3-Clause 2 * Copyright(c) 2010-2019 Intel Corporation 3 */ 4 5 #ifndef _RTE_COMMON_H_ 6 #define _RTE_COMMON_H_ 7 8 /** 9 * @file 10 * 11 * Generic, commonly-used macro and inline function definitions 12 * for DPDK. 13 */ 14 15 #include <assert.h> 16 #include <limits.h> 17 #include <stdint.h> 18 #include <stdalign.h> 19 20 #include <rte_config.h> 21 22 /* OS specific include */ 23 #include <rte_os.h> 24 25 #ifdef __cplusplus 26 extern "C" { 27 #endif 28 29 #ifndef RTE_TOOLCHAIN_MSVC 30 #ifndef typeof 31 #define typeof __typeof__ 32 #endif 33 #endif 34 35 #ifndef __cplusplus 36 #ifndef asm 37 #define asm __asm__ 38 #endif 39 #endif 40 41 #ifdef RTE_TOOLCHAIN_MSVC 42 #ifdef __cplusplus 43 #define __extension__ 44 #endif 45 #endif 46 47 #ifdef RTE_TOOLCHAIN_MSVC 48 #define __rte_constant(e) 0 49 #else 50 #define __rte_constant(e) __extension__(__builtin_constant_p(e)) 51 #endif 52 53 /* 54 * RTE_TOOLCHAIN_GCC is defined if the target is built with GCC, 55 * while a host application (like pmdinfogen) may have another compiler. 56 * RTE_CC_IS_GNU is true if the file is compiled with GCC, 57 * no matter it is a target or host application. 58 */ 59 #define RTE_CC_IS_GNU 0 60 #if defined __clang__ 61 #define RTE_CC_CLANG 62 #elif defined __INTEL_COMPILER 63 #define RTE_CC_ICC 64 #elif defined __GNUC__ 65 #define RTE_CC_GCC 66 #undef RTE_CC_IS_GNU 67 #define RTE_CC_IS_GNU 1 68 #endif 69 #if RTE_CC_IS_GNU 70 #define GCC_VERSION (__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + \ 71 __GNUC_PATCHLEVEL__) 72 #endif 73 74 /** 75 * Force type alignment 76 * 77 * This macro should be used when alignment of a struct or union type 78 * is required. For toolchain compatibility it should appear between 79 * the {struct,union} keyword and tag. e.g. 80 * 81 * struct __rte_aligned(8) tag { ... }; 82 * 83 * If alignment of an object/variable is required then this macro should 84 * not be used, instead prefer C11 alignas(a). 85 */ 86 #ifdef RTE_TOOLCHAIN_MSVC 87 #define __rte_aligned(a) __declspec(align(a)) 88 #else 89 #define __rte_aligned(a) __attribute__((__aligned__(a))) 90 #endif 91 92 #ifdef RTE_ARCH_STRICT_ALIGN 93 typedef uint64_t unaligned_uint64_t __rte_aligned(1); 94 typedef uint32_t unaligned_uint32_t __rte_aligned(1); 95 typedef uint16_t unaligned_uint16_t __rte_aligned(1); 96 #else 97 typedef uint64_t unaligned_uint64_t; 98 typedef uint32_t unaligned_uint32_t; 99 typedef uint16_t unaligned_uint16_t; 100 #endif 101 102 /** 103 * Force a structure to be packed 104 */ 105 #ifdef RTE_TOOLCHAIN_MSVC 106 #define __rte_packed 107 #else 108 #define __rte_packed __attribute__((__packed__)) 109 #endif 110 111 /** 112 * Macro to mark a type that is not subject to type-based aliasing rules 113 */ 114 #ifdef RTE_TOOLCHAIN_MSVC 115 #define __rte_may_alias 116 #else 117 #define __rte_may_alias __attribute__((__may_alias__)) 118 #endif 119 120 /******* Macro to mark functions and fields scheduled for removal *****/ 121 #ifdef RTE_TOOLCHAIN_MSVC 122 #define __rte_deprecated 123 #define __rte_deprecated_msg(msg) 124 #else 125 #define __rte_deprecated __attribute__((__deprecated__)) 126 #define __rte_deprecated_msg(msg) __attribute__((__deprecated__(msg))) 127 #endif 128 129 /** 130 * Macro to mark macros and defines scheduled for removal 131 */ 132 #if defined(RTE_CC_GCC) || defined(RTE_CC_CLANG) 133 #define RTE_PRAGMA(x) _Pragma(#x) 134 #define RTE_PRAGMA_WARNING(w) RTE_PRAGMA(GCC warning #w) 135 #define RTE_DEPRECATED(x) RTE_PRAGMA_WARNING(#x is deprecated) 136 #else 137 #define RTE_DEPRECATED(x) 138 #endif 139 140 /** 141 * Mark a function or variable to a weak reference. 142 */ 143 #define __rte_weak __attribute__((__weak__)) 144 145 /** 146 * Mark a function to be pure. 147 */ 148 #ifdef RTE_TOOLCHAIN_MSVC 149 #define __rte_pure 150 #else 151 #define __rte_pure __attribute__((pure)) 152 #endif 153 154 /** 155 * Force symbol to be generated even if it appears to be unused. 156 */ 157 #ifdef RTE_TOOLCHAIN_MSVC 158 #define __rte_used 159 #else 160 #define __rte_used __attribute__((used)) 161 #endif 162 163 /*********** Macros to eliminate unused variable warnings ********/ 164 165 /** 166 * short definition to mark a function parameter unused 167 */ 168 #ifdef RTE_TOOLCHAIN_MSVC 169 #define __rte_unused 170 #else 171 #define __rte_unused __attribute__((__unused__)) 172 #endif 173 174 /** 175 * Mark pointer as restricted with regard to pointer aliasing. 176 */ 177 #if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 199901L 178 #define __rte_restrict __restrict 179 #else 180 #define __rte_restrict restrict 181 #endif 182 183 /** 184 * definition to mark a variable or function parameter as used so 185 * as to avoid a compiler warning 186 */ 187 #define RTE_SET_USED(x) (void)(x) 188 189 /** 190 * Check format string and its arguments at compile-time. 191 * 192 * GCC on Windows assumes MS-specific format string by default, 193 * even if the underlying stdio implementation is ANSI-compliant, 194 * so this must be overridden. 195 */ 196 #ifdef RTE_TOOLCHAIN_MSVC 197 #define __rte_format_printf(format_index, first_arg) 198 #else 199 #if RTE_CC_IS_GNU 200 #define __rte_format_printf(format_index, first_arg) \ 201 __attribute__((format(gnu_printf, format_index, first_arg))) 202 #else 203 #define __rte_format_printf(format_index, first_arg) \ 204 __attribute__((format(printf, format_index, first_arg))) 205 #endif 206 #endif 207 208 /** 209 * Specify data or function section/segment. 210 */ 211 #ifdef RTE_TOOLCHAIN_MSVC 212 #define __rte_section(name) \ 213 __pragma(data_seg(name)) __declspec(allocate(name)) 214 #else 215 #define __rte_section(name) \ 216 __attribute__((section(name))) 217 #endif 218 219 /** 220 * Tells compiler that the function returns a value that points to 221 * memory, where the size is given by the one or two arguments. 222 * Used by compiler to validate object size. 223 */ 224 #if defined(RTE_CC_GCC) || defined(RTE_CC_CLANG) 225 #define __rte_alloc_size(...) \ 226 __attribute__((alloc_size(__VA_ARGS__))) 227 #else 228 #define __rte_alloc_size(...) 229 #endif 230 231 /** 232 * Tells the compiler that the function returns a value that points to 233 * memory aligned by a function argument. 234 * 235 * Note: not enabled on Clang because it warns if align argument is zero. 236 */ 237 #if defined(RTE_CC_GCC) 238 #define __rte_alloc_align(argno) \ 239 __attribute__((alloc_align(argno))) 240 #else 241 #define __rte_alloc_align(argno) 242 #endif 243 244 /** 245 * Tells the compiler this is a function like malloc and that the pointer 246 * returned cannot alias any other pointer (ie new memory). 247 */ 248 #if defined(RTE_CC_GCC) || defined(RTE_CC_CLANG) 249 #define __rte_malloc __attribute__((__malloc__)) 250 #else 251 #define __rte_malloc 252 #endif 253 254 /** 255 * With recent GCC versions also able to track that proper 256 * deallocator function is used for this pointer. 257 */ 258 #if defined(RTE_TOOLCHAIN_GCC) && (GCC_VERSION >= 110000) 259 #define __rte_dealloc(dealloc, argno) \ 260 __attribute__((malloc(dealloc, argno))) 261 #else 262 #define __rte_dealloc(dealloc, argno) 263 #endif 264 265 #define RTE_PRIORITY_LOG 101 266 #define RTE_PRIORITY_BUS 110 267 #define RTE_PRIORITY_CLASS 120 268 #define RTE_PRIORITY_LAST 65535 269 270 #define RTE_PRIO(prio) \ 271 RTE_PRIORITY_ ## prio 272 273 /** 274 * Run function before main() with high priority. 275 * 276 * @param func 277 * Constructor function. 278 * @param prio 279 * Priority number must be above 100. 280 * Lowest number is the first to run. 281 */ 282 #ifndef RTE_INIT_PRIO /* Allow to override from EAL */ 283 #ifndef RTE_TOOLCHAIN_MSVC 284 #define RTE_INIT_PRIO(func, prio) \ 285 static void __attribute__((constructor(RTE_PRIO(prio)), used)) func(void) 286 #else 287 /* definition from the Microsoft CRT */ 288 typedef int(__cdecl *_PIFV)(void); 289 290 #define CTOR_SECTION_LOG ".CRT$XIB" 291 #define CTOR_SECTION_BUS ".CRT$XIC" 292 #define CTOR_SECTION_CLASS ".CRT$XID" 293 #define CTOR_SECTION_LAST ".CRT$XIY" 294 295 #define CTOR_PRIORITY_TO_SECTION(priority) CTOR_SECTION_ ## priority 296 297 #define RTE_INIT_PRIO(name, priority) \ 298 static void name(void); \ 299 static int __cdecl name ## _thunk(void) { name(); return 0; } \ 300 __pragma(const_seg(CTOR_PRIORITY_TO_SECTION(priority))) \ 301 __declspec(allocate(CTOR_PRIORITY_TO_SECTION(priority))) \ 302 _PIFV name ## _pointer = &name ## _thunk; \ 303 __pragma(const_seg()) \ 304 static void name(void) 305 #endif 306 #endif 307 308 /** 309 * Run function before main() with low priority. 310 * 311 * The constructor will be run after prioritized constructors. 312 * 313 * @param func 314 * Constructor function. 315 */ 316 #define RTE_INIT(func) \ 317 RTE_INIT_PRIO(func, LAST) 318 319 /** 320 * Run after main() with low priority. 321 * 322 * @param func 323 * Destructor function name. 324 * @param prio 325 * Priority number must be above 100. 326 * Lowest number is the last to run. 327 */ 328 #ifndef RTE_FINI_PRIO /* Allow to override from EAL */ 329 #ifndef RTE_TOOLCHAIN_MSVC 330 #define RTE_FINI_PRIO(func, prio) \ 331 static void __attribute__((destructor(RTE_PRIO(prio)), used)) func(void) 332 #else 333 #define DTOR_SECTION_LOG "mydtor$B" 334 #define DTOR_SECTION_BUS "mydtor$C" 335 #define DTOR_SECTION_CLASS "mydtor$D" 336 #define DTOR_SECTION_LAST "mydtor$Y" 337 338 #define DTOR_PRIORITY_TO_SECTION(priority) DTOR_SECTION_ ## priority 339 340 #define RTE_FINI_PRIO(name, priority) \ 341 static void name(void); \ 342 __pragma(const_seg(DTOR_PRIORITY_TO_SECTION(priority))) \ 343 __declspec(allocate(DTOR_PRIORITY_TO_SECTION(priority))) void *name ## _pointer = &name; \ 344 __pragma(const_seg()) \ 345 static void name(void) 346 #endif 347 #endif 348 349 /** 350 * Run after main() with high priority. 351 * 352 * The destructor will be run *before* prioritized destructors. 353 * 354 * @param func 355 * Destructor function name. 356 */ 357 #define RTE_FINI(func) \ 358 RTE_FINI_PRIO(func, LAST) 359 360 /** 361 * Hint never returning function 362 */ 363 #ifdef RTE_TOOLCHAIN_MSVC 364 #define __rte_noreturn 365 #else 366 #define __rte_noreturn __attribute__((noreturn)) 367 #endif 368 369 /** 370 * Issue a warning in case the function's return value is ignored. 371 * 372 * The use of this attribute should be restricted to cases where 373 * ignoring the marked function's return value is almost always a 374 * bug. With GCC, some effort is required to make clear that ignoring 375 * the return value is intentional. The usual void-casting method to 376 * mark something unused as used does not suppress the warning with 377 * this compiler. 378 * 379 * @code{.c} 380 * __rte_warn_unused_result int foo(); 381 * 382 * void ignore_foo_result(void) { 383 * foo(); // generates a warning with all compilers 384 * 385 * (void)foo(); // still generates the warning with GCC (but not clang) 386 * 387 * int unused __rte_unused; 388 * unused = foo(); // does the trick with all compilers 389 * } 390 * @endcode 391 */ 392 #ifdef RTE_TOOLCHAIN_MSVC 393 #define __rte_warn_unused_result 394 #else 395 #define __rte_warn_unused_result __attribute__((warn_unused_result)) 396 #endif 397 398 /** 399 * Force a function to be inlined 400 */ 401 #ifdef RTE_TOOLCHAIN_MSVC 402 #define __rte_always_inline 403 #else 404 #define __rte_always_inline inline __attribute__((always_inline)) 405 #endif 406 407 /** 408 * Force a function to be noinlined 409 */ 410 #define __rte_noinline __attribute__((noinline)) 411 412 /** 413 * Hint function in the hot path 414 */ 415 #define __rte_hot __attribute__((hot)) 416 417 /** 418 * Hint function in the cold path 419 */ 420 #ifdef RTE_TOOLCHAIN_MSVC 421 #define __rte_cold 422 #else 423 #define __rte_cold __attribute__((cold)) 424 #endif 425 426 /** 427 * Disable AddressSanitizer on some code 428 */ 429 #ifdef RTE_MALLOC_ASAN 430 #ifdef RTE_CC_CLANG 431 #define __rte_no_asan __attribute__((no_sanitize("address", "hwaddress"))) 432 #else 433 #define __rte_no_asan __attribute__((no_sanitize_address)) 434 #endif 435 #else /* ! RTE_MALLOC_ASAN */ 436 #define __rte_no_asan 437 #endif 438 439 /*********** Macros for pointer arithmetic ********/ 440 441 /** 442 * add a byte-value offset to a pointer 443 */ 444 #define RTE_PTR_ADD(ptr, x) ((void*)((uintptr_t)(ptr) + (x))) 445 446 /** 447 * subtract a byte-value offset from a pointer 448 */ 449 #define RTE_PTR_SUB(ptr, x) ((void *)((uintptr_t)(ptr) - (x))) 450 451 /** 452 * get the difference between two pointer values, i.e. how far apart 453 * in bytes are the locations they point two. It is assumed that 454 * ptr1 is greater than ptr2. 455 */ 456 #define RTE_PTR_DIFF(ptr1, ptr2) ((uintptr_t)(ptr1) - (uintptr_t)(ptr2)) 457 458 /** 459 * Workaround to cast a const field of a structure to non-const type. 460 */ 461 #define RTE_CAST_FIELD(var, field, type) \ 462 (*(type *)((uintptr_t)(var) + offsetof(typeof(*(var)), field))) 463 464 /*********** Macros/static functions for doing alignment ********/ 465 466 467 /** 468 * Macro to align a pointer to a given power-of-two. The resultant 469 * pointer will be a pointer of the same type as the first parameter, and 470 * point to an address no higher than the first parameter. Second parameter 471 * must be a power-of-two value. 472 */ 473 #define RTE_PTR_ALIGN_FLOOR(ptr, align) \ 474 ((typeof(ptr))RTE_ALIGN_FLOOR((uintptr_t)(ptr), align)) 475 476 /** 477 * Macro to align a value to a given power-of-two. The resultant value 478 * will be of the same type as the first parameter, and will be no 479 * bigger than the first parameter. Second parameter must be a 480 * power-of-two value. 481 */ 482 #define RTE_ALIGN_FLOOR(val, align) \ 483 (typeof(val))((val) & (~((typeof(val))((align) - 1)))) 484 485 /** 486 * Macro to align a pointer to a given power-of-two. The resultant 487 * pointer will be a pointer of the same type as the first parameter, and 488 * point to an address no lower than the first parameter. Second parameter 489 * must be a power-of-two value. 490 */ 491 #define RTE_PTR_ALIGN_CEIL(ptr, align) \ 492 RTE_PTR_ALIGN_FLOOR((typeof(ptr))RTE_PTR_ADD(ptr, (align) - 1), align) 493 494 /** 495 * Macro to align a value to a given power-of-two. The resultant value 496 * will be of the same type as the first parameter, and will be no lower 497 * than the first parameter. Second parameter must be a power-of-two 498 * value. 499 */ 500 #define RTE_ALIGN_CEIL(val, align) \ 501 RTE_ALIGN_FLOOR(((val) + ((typeof(val)) (align) - 1)), align) 502 503 /** 504 * Macro to align a pointer to a given power-of-two. The resultant 505 * pointer will be a pointer of the same type as the first parameter, and 506 * point to an address no lower than the first parameter. Second parameter 507 * must be a power-of-two value. 508 * This function is the same as RTE_PTR_ALIGN_CEIL 509 */ 510 #define RTE_PTR_ALIGN(ptr, align) RTE_PTR_ALIGN_CEIL(ptr, align) 511 512 /** 513 * Macro to align a value to a given power-of-two. The resultant 514 * value will be of the same type as the first parameter, and 515 * will be no lower than the first parameter. Second parameter 516 * must be a power-of-two value. 517 * This function is the same as RTE_ALIGN_CEIL 518 */ 519 #define RTE_ALIGN(val, align) RTE_ALIGN_CEIL(val, align) 520 521 /** 522 * Macro to align a value to the multiple of given value. The resultant 523 * value will be of the same type as the first parameter and will be no lower 524 * than the first parameter. 525 */ 526 #define RTE_ALIGN_MUL_CEIL(v, mul) \ 527 ((((v) + (typeof(v))(mul) - 1) / ((typeof(v))(mul))) * (typeof(v))(mul)) 528 529 /** 530 * Macro to align a value to the multiple of given value. The resultant 531 * value will be of the same type as the first parameter and will be no higher 532 * than the first parameter. 533 */ 534 #define RTE_ALIGN_MUL_FLOOR(v, mul) \ 535 (((v) / ((typeof(v))(mul))) * (typeof(v))(mul)) 536 537 /** 538 * Macro to align value to the nearest multiple of the given value. 539 * The resultant value might be greater than or less than the first parameter 540 * whichever difference is the lowest. 541 */ 542 #define RTE_ALIGN_MUL_NEAR(v, mul) \ 543 __extension__ ({ \ 544 typeof(v) ceil = RTE_ALIGN_MUL_CEIL(v, mul); \ 545 typeof(v) floor = RTE_ALIGN_MUL_FLOOR(v, mul); \ 546 (ceil - (v)) > ((v) - floor) ? floor : ceil; \ 547 }) 548 549 /** 550 * Checks if a pointer is aligned to a given power-of-two value 551 * 552 * @param ptr 553 * The pointer whose alignment is to be checked 554 * @param align 555 * The power-of-two value to which the ptr should be aligned 556 * 557 * @return 558 * True(1) where the pointer is correctly aligned, false(0) otherwise 559 */ 560 static inline int 561 rte_is_aligned(const void * const __rte_restrict ptr, const unsigned int align) 562 { 563 return ((uintptr_t)ptr & (align - 1)) == 0; 564 } 565 566 /*********** Macros for compile type checks ********/ 567 568 /* Workaround for toolchain issues with missing C11 macro in FreeBSD */ 569 #if !defined(static_assert) && !defined(__cplusplus) 570 #define static_assert _Static_assert 571 #endif 572 573 /** 574 * Triggers an error at compilation time if the condition is true. 575 * 576 * The do { } while(0) exists to workaround a bug in clang (#55821) 577 * where it would not handle _Static_assert in a switch case. 578 */ 579 #define RTE_BUILD_BUG_ON(condition) do { static_assert(!(condition), #condition); } while (0) 580 581 /*********** Cache line related macros ********/ 582 583 /** Cache line mask. */ 584 #define RTE_CACHE_LINE_MASK (RTE_CACHE_LINE_SIZE-1) 585 586 /** Return the first cache-aligned value greater or equal to size. */ 587 #define RTE_CACHE_LINE_ROUNDUP(size) RTE_ALIGN_CEIL(size, RTE_CACHE_LINE_SIZE) 588 589 /** Cache line size in terms of log2 */ 590 #if RTE_CACHE_LINE_SIZE == 64 591 #define RTE_CACHE_LINE_SIZE_LOG2 6 592 #elif RTE_CACHE_LINE_SIZE == 128 593 #define RTE_CACHE_LINE_SIZE_LOG2 7 594 #else 595 #error "Unsupported cache line size" 596 #endif 597 598 /** Minimum Cache line size. */ 599 #define RTE_CACHE_LINE_MIN_SIZE 64 600 601 /** Force alignment to cache line. */ 602 #define __rte_cache_aligned __rte_aligned(RTE_CACHE_LINE_SIZE) 603 604 /** Force minimum cache line alignment. */ 605 #define __rte_cache_min_aligned __rte_aligned(RTE_CACHE_LINE_MIN_SIZE) 606 607 #define _RTE_CACHE_GUARD_HELPER2(unique) \ 608 alignas(RTE_CACHE_LINE_SIZE) \ 609 char cache_guard_ ## unique[RTE_CACHE_LINE_SIZE * RTE_CACHE_GUARD_LINES] 610 #define _RTE_CACHE_GUARD_HELPER1(unique) _RTE_CACHE_GUARD_HELPER2(unique) 611 /** 612 * Empty cache lines, to guard against false sharing-like effects 613 * on systems with a next-N-lines hardware prefetcher. 614 * 615 * Use as spacing between data accessed by different lcores, 616 * to prevent cache thrashing on hardware with speculative prefetching. 617 */ 618 #define RTE_CACHE_GUARD _RTE_CACHE_GUARD_HELPER1(__COUNTER__) 619 620 /*********** PA/IOVA type definitions ********/ 621 622 /** Physical address */ 623 typedef uint64_t phys_addr_t; 624 #define RTE_BAD_PHYS_ADDR ((phys_addr_t)-1) 625 626 /** 627 * IO virtual address type. 628 * When the physical addressing mode (IOVA as PA) is in use, 629 * the translation from an IO virtual address (IOVA) to a physical address 630 * is a direct mapping, i.e. the same value. 631 * Otherwise, in virtual mode (IOVA as VA), an IOMMU may do the translation. 632 */ 633 typedef uint64_t rte_iova_t; 634 #define RTE_BAD_IOVA ((rte_iova_t)-1) 635 636 /*********** Structure alignment markers ********/ 637 638 #ifndef RTE_TOOLCHAIN_MSVC 639 640 /** Generic marker for any place in a structure. */ 641 __extension__ typedef void *RTE_MARKER[0]; 642 /** Marker for 1B alignment in a structure. */ 643 __extension__ typedef uint8_t RTE_MARKER8[0]; 644 /** Marker for 2B alignment in a structure. */ 645 __extension__ typedef uint16_t RTE_MARKER16[0]; 646 /** Marker for 4B alignment in a structure. */ 647 __extension__ typedef uint32_t RTE_MARKER32[0]; 648 /** Marker for 8B alignment in a structure. */ 649 __extension__ typedef uint64_t RTE_MARKER64[0]; 650 651 #endif 652 653 /*********** Macros for calculating min and max **********/ 654 655 /** 656 * Macro to return the minimum of two numbers 657 */ 658 #define RTE_MIN(a, b) \ 659 __extension__ ({ \ 660 typeof (a) _a = (a); \ 661 typeof (b) _b = (b); \ 662 _a < _b ? _a : _b; \ 663 }) 664 665 /** 666 * Macro to return the minimum of two numbers 667 * 668 * As opposed to RTE_MIN, it does not use temporary variables so it is not safe 669 * if a or b is an expression. Yet it is guaranteed to be constant for use in 670 * static_assert(). 671 */ 672 #define RTE_MIN_T(a, b, t) \ 673 ((t)(a) < (t)(b) ? (t)(a) : (t)(b)) 674 675 /** 676 * Macro to return the maximum of two numbers 677 */ 678 #define RTE_MAX(a, b) \ 679 __extension__ ({ \ 680 typeof (a) _a = (a); \ 681 typeof (b) _b = (b); \ 682 _a > _b ? _a : _b; \ 683 }) 684 685 /** 686 * Macro to return the maximum of two numbers 687 * 688 * As opposed to RTE_MAX, it does not use temporary variables so it is not safe 689 * if a or b is an expression. Yet it is guaranteed to be constant for use in 690 * static_assert(). 691 */ 692 #define RTE_MAX_T(a, b, t) \ 693 ((t)(a) > (t)(b) ? (t)(a) : (t)(b)) 694 695 /*********** Other general functions / macros ********/ 696 697 #ifndef offsetof 698 /** Return the offset of a field in a structure. */ 699 #define offsetof(TYPE, MEMBER) __builtin_offsetof (TYPE, MEMBER) 700 #endif 701 702 /** 703 * Return pointer to the wrapping struct instance. 704 * 705 * Example: 706 * 707 * struct wrapper { 708 * ... 709 * struct child c; 710 * ... 711 * }; 712 * 713 * struct child *x = obtain(...); 714 * struct wrapper *w = container_of(x, struct wrapper, c); 715 */ 716 #ifndef container_of 717 #ifdef RTE_TOOLCHAIN_MSVC 718 #define container_of(ptr, type, member) \ 719 ((type *)((uintptr_t)(ptr) - offsetof(type, member))) 720 #else 721 #define container_of(ptr, type, member) __extension__ ({ \ 722 const typeof(((type *)0)->member) *_ptr = (ptr); \ 723 __rte_unused type *_target_ptr = \ 724 (type *)(ptr); \ 725 (type *)(((uintptr_t)_ptr) - offsetof(type, member)); \ 726 }) 727 #endif 728 #endif 729 730 /** Swap two variables. */ 731 #define RTE_SWAP(a, b) \ 732 __extension__ ({ \ 733 typeof (a) _a = a; \ 734 a = b; \ 735 b = _a; \ 736 }) 737 738 /** 739 * Get the size of a field in a structure. 740 * 741 * @param type 742 * The type of the structure. 743 * @param field 744 * The field in the structure. 745 * @return 746 * The size of the field in the structure, in bytes. 747 */ 748 #define RTE_SIZEOF_FIELD(type, field) (sizeof(((type *)0)->field)) 749 750 #define _RTE_STR(x) #x 751 /** Take a macro value and get a string version of it */ 752 #define RTE_STR(x) _RTE_STR(x) 753 754 /** 755 * ISO C helpers to modify format strings using variadic macros. 756 * This is a replacement for the ", ## __VA_ARGS__" GNU extension. 757 * An empty %s argument is appended to avoid a dangling comma. 758 */ 759 #define RTE_FMT(fmt, ...) fmt "%.0s", __VA_ARGS__ "" 760 #define RTE_FMT_HEAD(fmt, ...) fmt 761 #define RTE_FMT_TAIL(fmt, ...) __VA_ARGS__ 762 763 /** Mask value of type "tp" for the first "ln" bit set. */ 764 #define RTE_LEN2MASK(ln, tp) \ 765 ((tp)((uint64_t)-1 >> (sizeof(uint64_t) * CHAR_BIT - (ln)))) 766 767 /** Number of elements in the array. */ 768 #define RTE_DIM(a) (sizeof (a) / sizeof ((a)[0])) 769 770 /** 771 * Converts a numeric string to the equivalent uint64_t value. 772 * As well as straight number conversion, also recognises the suffixes 773 * k, m and g for kilobytes, megabytes and gigabytes respectively. 774 * 775 * If a negative number is passed in i.e. a string with the first non-black 776 * character being "-", zero is returned. Zero is also returned in the case of 777 * an error with the strtoull call in the function. 778 * 779 * @param str 780 * String containing number to convert. 781 * @return 782 * Number. 783 */ 784 uint64_t 785 rte_str_to_size(const char *str); 786 787 /** 788 * Function to terminate the application immediately, printing an error 789 * message and returning the exit_code back to the shell. 790 * 791 * This function never returns 792 * 793 * @param exit_code 794 * The exit code to be returned by the application 795 * @param format 796 * The format string to be used for printing the message. This can include 797 * printf format characters which will be expanded using any further parameters 798 * to the function. 799 */ 800 __rte_noreturn void 801 rte_exit(int exit_code, const char *format, ...) 802 __rte_format_printf(2, 3); 803 804 #ifdef __cplusplus 805 } 806 #endif 807 808 #endif 809