xref: /freebsd/sys/contrib/dpdk_rte_lpm/rte_common.h (revision 537d134373141c2d25bfb24af6d661d0e6102927)
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 #ifdef __cplusplus
16 extern "C" {
17 #endif
18 
19 //#include <rte_config.h>
20 
21 /* OS specific include */
22 //#include <rte_os.h>
23 
24 #ifndef typeof
25 #define typeof __typeof__
26 #endif
27 
28 #ifndef asm
29 #define asm __asm__
30 #endif
31 
32 /** C extension macro for environments lacking C11 features. */
33 #if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 201112L
34 #define RTE_STD_C11 __extension__
35 #else
36 #define RTE_STD_C11
37 #endif
38 
39 /*
40  * RTE_TOOLCHAIN_GCC is defined if the target is built with GCC,
41  * while a host application (like pmdinfogen) may have another compiler.
42  * RTE_CC_IS_GNU is true if the file is compiled with GCC,
43  * no matter it is a target or host application.
44  */
45 #define RTE_CC_IS_GNU 0
46 #if defined __clang__
47 #define RTE_CC_CLANG
48 #elif defined __INTEL_COMPILER
49 #define RTE_CC_ICC
50 #elif defined __GNUC__
51 #define RTE_CC_GCC
52 #undef RTE_CC_IS_GNU
53 #define RTE_CC_IS_GNU 1
54 #endif
55 #if RTE_CC_IS_GNU
56 #define GCC_VERSION (__GNUC__ * 10000 + __GNUC_MINOR__ * 100 +	\
57 		__GNUC_PATCHLEVEL__)
58 #endif
59 
60 /**
61  * Force alignment
62  */
63 #define __rte_aligned(a) __attribute__((__aligned__(a)))
64 
65 #ifdef RTE_ARCH_STRICT_ALIGN
66 typedef uint64_t unaligned_uint64_t __rte_aligned(1);
67 typedef uint32_t unaligned_uint32_t __rte_aligned(1);
68 typedef uint16_t unaligned_uint16_t __rte_aligned(1);
69 #else
70 typedef uint64_t unaligned_uint64_t;
71 typedef uint32_t unaligned_uint32_t;
72 typedef uint16_t unaligned_uint16_t;
73 #endif
74 
75 /**
76  * Force a structure to be packed
77  */
78 #define __rte_packed __attribute__((__packed__))
79 
80 /******* Macro to mark functions and fields scheduled for removal *****/
81 #define __rte_deprecated	__attribute__((__deprecated__))
82 
83 /**
84  * Mark a function or variable to a weak reference.
85  */
86 #define __rte_weak __attribute__((__weak__))
87 
88 /**
89  * Force symbol to be generated even if it appears to be unused.
90  */
91 #define __rte_used __attribute__((used))
92 
93 /*********** Macros to eliminate unused variable warnings ********/
94 
95 /**
96  * short definition to mark a function parameter unused
97  */
98 #define __rte_unused __attribute__((__unused__))
99 
100 /**
101  * definition to mark a variable or function parameter as used so
102  * as to avoid a compiler warning
103  */
104 #define RTE_SET_USED(x) (void)(x)
105 
106 /**
107  * Check format string and its arguments at compile-time.
108  *
109  * GCC on Windows assumes MS-specific format string by default,
110  * even if the underlying stdio implementation is ANSI-compliant,
111  * so this must be overridden.
112  */
113 #if RTE_CC_IS_GNU
114 #define __rte_format_printf(format_index, first_arg) \
115 	__attribute__((format(gnu_printf, format_index, first_arg)))
116 #else
117 #define __rte_format_printf(format_index, first_arg) \
118 	__attribute__((format(printf, format_index, first_arg)))
119 #endif
120 
121 #define RTE_PRIORITY_LOG 101
122 #define RTE_PRIORITY_BUS 110
123 #define RTE_PRIORITY_CLASS 120
124 #define RTE_PRIORITY_LAST 65535
125 
126 #define RTE_PRIO(prio) \
127 	RTE_PRIORITY_ ## prio
128 
129 /**
130  * Run function before main() with high priority.
131  *
132  * @param func
133  *   Constructor function.
134  * @param prio
135  *   Priority number must be above 100.
136  *   Lowest number is the first to run.
137  */
138 #ifndef RTE_INIT_PRIO /* Allow to override from EAL */
139 #define RTE_INIT_PRIO(func, prio) \
140 static void __attribute__((constructor(RTE_PRIO(prio)), used)) func(void)
141 #endif
142 
143 /**
144  * Run function before main() with low priority.
145  *
146  * The constructor will be run after prioritized constructors.
147  *
148  * @param func
149  *   Constructor function.
150  */
151 #define RTE_INIT(func) \
152 	RTE_INIT_PRIO(func, LAST)
153 
154 /**
155  * Run after main() with low priority.
156  *
157  * @param func
158  *   Destructor function name.
159  * @param prio
160  *   Priority number must be above 100.
161  *   Lowest number is the last to run.
162  */
163 #ifndef RTE_FINI_PRIO /* Allow to override from EAL */
164 #define RTE_FINI_PRIO(func, prio) \
165 static void __attribute__((destructor(RTE_PRIO(prio)), used)) func(void)
166 #endif
167 
168 /**
169  * Run after main() with high priority.
170  *
171  * The destructor will be run *before* prioritized destructors.
172  *
173  * @param func
174  *   Destructor function name.
175  */
176 #define RTE_FINI(func) \
177 	RTE_FINI_PRIO(func, LAST)
178 
179 /**
180  * Hint never returning function
181  */
182 #define __rte_noreturn __attribute__((noreturn))
183 
184 /**
185  * Force a function to be inlined
186  */
187 #define __rte_always_inline inline __attribute__((always_inline))
188 
189 /**
190  * Force a function to be noinlined
191  */
192 #define __rte_noinline __attribute__((noinline))
193 
194 /**
195  * Hint function in the hot path
196  */
197 #define __rte_hot __attribute__((hot))
198 
199 /**
200  * Hint function in the cold path
201  */
202 #define __rte_cold __attribute__((cold))
203 
204 /*********** Macros for pointer arithmetic ********/
205 
206 /**
207  * add a byte-value offset to a pointer
208  */
209 #define RTE_PTR_ADD(ptr, x) ((void*)((uintptr_t)(ptr) + (x)))
210 
211 /**
212  * subtract a byte-value offset from a pointer
213  */
214 #define RTE_PTR_SUB(ptr, x) ((void*)((uintptr_t)ptr - (x)))
215 
216 /**
217  * get the difference between two pointer values, i.e. how far apart
218  * in bytes are the locations they point two. It is assumed that
219  * ptr1 is greater than ptr2.
220  */
221 #define RTE_PTR_DIFF(ptr1, ptr2) ((uintptr_t)(ptr1) - (uintptr_t)(ptr2))
222 
223 /**
224  * Workaround to cast a const field of a structure to non-const type.
225  */
226 #define RTE_CAST_FIELD(var, field, type) \
227 	(*(type *)((uintptr_t)(var) + offsetof(typeof(*(var)), field)))
228 
229 /*********** Macros/static functions for doing alignment ********/
230 
231 
232 /**
233  * Macro to align a pointer to a given power-of-two. The resultant
234  * pointer will be a pointer of the same type as the first parameter, and
235  * point to an address no higher than the first parameter. Second parameter
236  * must be a power-of-two value.
237  */
238 #define RTE_PTR_ALIGN_FLOOR(ptr, align) \
239 	((typeof(ptr))RTE_ALIGN_FLOOR((uintptr_t)ptr, align))
240 
241 /**
242  * Macro to align a value to a given power-of-two. The resultant value
243  * will be of the same type as the first parameter, and will be no
244  * bigger than the first parameter. Second parameter must be a
245  * power-of-two value.
246  */
247 #define RTE_ALIGN_FLOOR(val, align) \
248 	(typeof(val))((val) & (~((typeof(val))((align) - 1))))
249 
250 /**
251  * Macro to align a pointer to a given power-of-two. The resultant
252  * pointer will be a pointer of the same type as the first parameter, and
253  * point to an address no lower than the first parameter. Second parameter
254  * must be a power-of-two value.
255  */
256 #define RTE_PTR_ALIGN_CEIL(ptr, align) \
257 	RTE_PTR_ALIGN_FLOOR((typeof(ptr))RTE_PTR_ADD(ptr, (align) - 1), align)
258 
259 /**
260  * Macro to align a value to a given power-of-two. The resultant value
261  * will be of the same type as the first parameter, and will be no lower
262  * than the first parameter. Second parameter must be a power-of-two
263  * value.
264  */
265 #define RTE_ALIGN_CEIL(val, align) \
266 	RTE_ALIGN_FLOOR(((val) + ((typeof(val)) (align) - 1)), align)
267 
268 /**
269  * Macro to align a pointer to a given power-of-two. The resultant
270  * pointer will be a pointer of the same type as the first parameter, and
271  * point to an address no lower than the first parameter. Second parameter
272  * must be a power-of-two value.
273  * This function is the same as RTE_PTR_ALIGN_CEIL
274  */
275 #define RTE_PTR_ALIGN(ptr, align) RTE_PTR_ALIGN_CEIL(ptr, align)
276 
277 /**
278  * Macro to align a value to a given power-of-two. The resultant
279  * value will be of the same type as the first parameter, and
280  * will be no lower than the first parameter. Second parameter
281  * must be a power-of-two value.
282  * This function is the same as RTE_ALIGN_CEIL
283  */
284 #define RTE_ALIGN(val, align) RTE_ALIGN_CEIL(val, align)
285 
286 /**
287  * Macro to align a value to the multiple of given value. The resultant
288  * value will be of the same type as the first parameter and will be no lower
289  * than the first parameter.
290  */
291 #define RTE_ALIGN_MUL_CEIL(v, mul) \
292 	(((v + (typeof(v))(mul) - 1) / ((typeof(v))(mul))) * (typeof(v))(mul))
293 
294 /**
295  * Macro to align a value to the multiple of given value. The resultant
296  * value will be of the same type as the first parameter and will be no higher
297  * than the first parameter.
298  */
299 #define RTE_ALIGN_MUL_FLOOR(v, mul) \
300 	((v / ((typeof(v))(mul))) * (typeof(v))(mul))
301 
302 /**
303  * Macro to align value to the nearest multiple of the given value.
304  * The resultant value might be greater than or less than the first parameter
305  * whichever difference is the lowest.
306  */
307 #define RTE_ALIGN_MUL_NEAR(v, mul)				\
308 	({							\
309 		typeof(v) ceil = RTE_ALIGN_MUL_CEIL(v, mul);	\
310 		typeof(v) floor = RTE_ALIGN_MUL_FLOOR(v, mul);	\
311 		(ceil - v) > (v - floor) ? floor : ceil;	\
312 	})
313 
314 /**
315  * Checks if a pointer is aligned to a given power-of-two value
316  *
317  * @param ptr
318  *   The pointer whose alignment is to be checked
319  * @param align
320  *   The power-of-two value to which the ptr should be aligned
321  *
322  * @return
323  *   True(1) where the pointer is correctly aligned, false(0) otherwise
324  */
325 static inline int
rte_is_aligned(void * ptr,unsigned align)326 rte_is_aligned(void *ptr, unsigned align)
327 {
328 	return RTE_PTR_ALIGN(ptr, align) == ptr;
329 }
330 
331 /*********** Macros for compile type checks ********/
332 
333 /**
334  * Triggers an error at compilation time if the condition is true.
335  */
336 #define RTE_BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
337 
338 /*********** Cache line related macros ********/
339 
340 /** Cache line mask. */
341 #define RTE_CACHE_LINE_MASK (RTE_CACHE_LINE_SIZE-1)
342 
343 /** Return the first cache-aligned value greater or equal to size. */
344 #define RTE_CACHE_LINE_ROUNDUP(size) \
345 	(RTE_CACHE_LINE_SIZE * ((size + RTE_CACHE_LINE_SIZE - 1) / \
346 	RTE_CACHE_LINE_SIZE))
347 
348 /** Cache line size in terms of log2 */
349 #if RTE_CACHE_LINE_SIZE == 64
350 #define RTE_CACHE_LINE_SIZE_LOG2 6
351 #elif RTE_CACHE_LINE_SIZE == 128
352 #define RTE_CACHE_LINE_SIZE_LOG2 7
353 #else
354 #error "Unsupported cache line size"
355 #endif
356 
357 /** Minimum Cache line size. */
358 #define RTE_CACHE_LINE_MIN_SIZE 64
359 
360 /** Force alignment to cache line. */
361 #define __rte_cache_aligned __rte_aligned(RTE_CACHE_LINE_SIZE)
362 
363 /** Force minimum cache line alignment. */
364 #define __rte_cache_min_aligned __rte_aligned(RTE_CACHE_LINE_MIN_SIZE)
365 
366 /*********** PA/IOVA type definitions ********/
367 
368 /** Physical address */
369 typedef uint64_t phys_addr_t;
370 #define RTE_BAD_PHYS_ADDR ((phys_addr_t)-1)
371 
372 /**
373  * IO virtual address type.
374  * When the physical addressing mode (IOVA as PA) is in use,
375  * the translation from an IO virtual address (IOVA) to a physical address
376  * is a direct mapping, i.e. the same value.
377  * Otherwise, in virtual mode (IOVA as VA), an IOMMU may do the translation.
378  */
379 typedef uint64_t rte_iova_t;
380 #define RTE_BAD_IOVA ((rte_iova_t)-1)
381 
382 /*********** Structure alignment markers ********/
383 
384 /** Generic marker for any place in a structure. */
385 __extension__ typedef void    *RTE_MARKER[0];
386 /** Marker for 1B alignment in a structure. */
387 __extension__ typedef uint8_t  RTE_MARKER8[0];
388 /** Marker for 2B alignment in a structure. */
389 __extension__ typedef uint16_t RTE_MARKER16[0];
390 /** Marker for 4B alignment in a structure. */
391 __extension__ typedef uint32_t RTE_MARKER32[0];
392 /** Marker for 8B alignment in a structure. */
393 __extension__ typedef uint64_t RTE_MARKER64[0];
394 
395 /**
396  * Combines 32b inputs most significant set bits into the least
397  * significant bits to construct a value with the same MSBs as x
398  * but all 1's under it.
399  *
400  * @param x
401  *    The integer whose MSBs need to be combined with its LSBs
402  * @return
403  *    The combined value.
404  */
405 static inline uint32_t
rte_combine32ms1b(register uint32_t x)406 rte_combine32ms1b(register uint32_t x)
407 {
408 	x |= x >> 1;
409 	x |= x >> 2;
410 	x |= x >> 4;
411 	x |= x >> 8;
412 	x |= x >> 16;
413 
414 	return x;
415 }
416 
417 /**
418  * Combines 64b inputs most significant set bits into the least
419  * significant bits to construct a value with the same MSBs as x
420  * but all 1's under it.
421  *
422  * @param v
423  *    The integer whose MSBs need to be combined with its LSBs
424  * @return
425  *    The combined value.
426  */
427 static inline uint64_t
rte_combine64ms1b(register uint64_t v)428 rte_combine64ms1b(register uint64_t v)
429 {
430 	v |= v >> 1;
431 	v |= v >> 2;
432 	v |= v >> 4;
433 	v |= v >> 8;
434 	v |= v >> 16;
435 	v |= v >> 32;
436 
437 	return v;
438 }
439 
440 /*********** Macros to work with powers of 2 ********/
441 
442 /**
443  * Macro to return 1 if n is a power of 2, 0 otherwise
444  */
445 #define RTE_IS_POWER_OF_2(n) ((n) && !(((n) - 1) & (n)))
446 
447 /**
448  * Returns true if n is a power of 2
449  * @param n
450  *     Number to check
451  * @return 1 if true, 0 otherwise
452  */
453 static inline int
rte_is_power_of_2(uint32_t n)454 rte_is_power_of_2(uint32_t n)
455 {
456 	return n && !(n & (n - 1));
457 }
458 
459 /**
460  * Aligns input parameter to the next power of 2
461  *
462  * @param x
463  *   The integer value to align
464  *
465  * @return
466  *   Input parameter aligned to the next power of 2
467  */
468 static inline uint32_t
rte_align32pow2(uint32_t x)469 rte_align32pow2(uint32_t x)
470 {
471 	x--;
472 	x = rte_combine32ms1b(x);
473 
474 	return x + 1;
475 }
476 
477 /**
478  * Aligns input parameter to the previous power of 2
479  *
480  * @param x
481  *   The integer value to align
482  *
483  * @return
484  *   Input parameter aligned to the previous power of 2
485  */
486 static inline uint32_t
rte_align32prevpow2(uint32_t x)487 rte_align32prevpow2(uint32_t x)
488 {
489 	x = rte_combine32ms1b(x);
490 
491 	return x - (x >> 1);
492 }
493 
494 /**
495  * Aligns 64b input parameter to the next power of 2
496  *
497  * @param v
498  *   The 64b value to align
499  *
500  * @return
501  *   Input parameter aligned to the next power of 2
502  */
503 static inline uint64_t
rte_align64pow2(uint64_t v)504 rte_align64pow2(uint64_t v)
505 {
506 	v--;
507 	v = rte_combine64ms1b(v);
508 
509 	return v + 1;
510 }
511 
512 /**
513  * Aligns 64b input parameter to the previous power of 2
514  *
515  * @param v
516  *   The 64b value to align
517  *
518  * @return
519  *   Input parameter aligned to the previous power of 2
520  */
521 static inline uint64_t
rte_align64prevpow2(uint64_t v)522 rte_align64prevpow2(uint64_t v)
523 {
524 	v = rte_combine64ms1b(v);
525 
526 	return v - (v >> 1);
527 }
528 
529 /*********** Macros for calculating min and max **********/
530 
531 /**
532  * Macro to return the minimum of two numbers
533  */
534 #define RTE_MIN(a, b) \
535 	__extension__ ({ \
536 		typeof (a) _a = (a); \
537 		typeof (b) _b = (b); \
538 		_a < _b ? _a : _b; \
539 	})
540 
541 /**
542  * Macro to return the maximum of two numbers
543  */
544 #define RTE_MAX(a, b) \
545 	__extension__ ({ \
546 		typeof (a) _a = (a); \
547 		typeof (b) _b = (b); \
548 		_a > _b ? _a : _b; \
549 	})
550 
551 /*********** Other general functions / macros ********/
552 
553 /**
554  * Searches the input parameter for the least significant set bit
555  * (starting from zero).
556  * If a least significant 1 bit is found, its bit index is returned.
557  * If the content of the input parameter is zero, then the content of the return
558  * value is undefined.
559  * @param v
560  *     input parameter, should not be zero.
561  * @return
562  *     least significant set bit in the input parameter.
563  */
564 static inline uint32_t
rte_bsf32(uint32_t v)565 rte_bsf32(uint32_t v)
566 {
567 	return (uint32_t)__builtin_ctz(v);
568 }
569 
570 /**
571  * Searches the input parameter for the least significant set bit
572  * (starting from zero). Safe version (checks for input parameter being zero).
573  *
574  * @warning ``pos`` must be a valid pointer. It is not checked!
575  *
576  * @param v
577  *     The input parameter.
578  * @param pos
579  *     If ``v`` was not 0, this value will contain position of least significant
580  *     bit within the input parameter.
581  * @return
582  *     Returns 0 if ``v`` was 0, otherwise returns 1.
583  */
584 static inline int
rte_bsf32_safe(uint64_t v,uint32_t * pos)585 rte_bsf32_safe(uint64_t v, uint32_t *pos)
586 {
587 	if (v == 0)
588 		return 0;
589 
590 	*pos = rte_bsf32(v);
591 	return 1;
592 }
593 
594 /**
595  * Return the rounded-up log2 of a integer.
596  *
597  * @note Contrary to the logarithm mathematical operation,
598  * rte_log2_u32(0) == 0 and not -inf.
599  *
600  * @param v
601  *     The input parameter.
602  * @return
603  *     The rounded-up log2 of the input, or 0 if the input is 0.
604  */
605 static inline uint32_t
rte_log2_u32(uint32_t v)606 rte_log2_u32(uint32_t v)
607 {
608 	if (v == 0)
609 		return 0;
610 	v = rte_align32pow2(v);
611 	return rte_bsf32(v);
612 }
613 
614 
615 /**
616  * Return the last (most-significant) bit set.
617  *
618  * @note The last (most significant) bit is at position 32.
619  * @note rte_fls_u32(0) = 0, rte_fls_u32(1) = 1, rte_fls_u32(0x80000000) = 32
620  *
621  * @param x
622  *     The input parameter.
623  * @return
624  *     The last (most-significant) bit set, or 0 if the input is 0.
625  */
626 static inline int
rte_fls_u32(uint32_t x)627 rte_fls_u32(uint32_t x)
628 {
629 	return (x == 0) ? 0 : 32 - __builtin_clz(x);
630 }
631 
632 /**
633  * Searches the input parameter for the least significant set bit
634  * (starting from zero).
635  * If a least significant 1 bit is found, its bit index is returned.
636  * If the content of the input parameter is zero, then the content of the return
637  * value is undefined.
638  * @param v
639  *     input parameter, should not be zero.
640  * @return
641  *     least significant set bit in the input parameter.
642  */
643 static inline int
rte_bsf64(uint64_t v)644 rte_bsf64(uint64_t v)
645 {
646 	return (uint32_t)__builtin_ctzll(v);
647 }
648 
649 /**
650  * Searches the input parameter for the least significant set bit
651  * (starting from zero). Safe version (checks for input parameter being zero).
652  *
653  * @warning ``pos`` must be a valid pointer. It is not checked!
654  *
655  * @param v
656  *     The input parameter.
657  * @param pos
658  *     If ``v`` was not 0, this value will contain position of least significant
659  *     bit within the input parameter.
660  * @return
661  *     Returns 0 if ``v`` was 0, otherwise returns 1.
662  */
663 static inline int
rte_bsf64_safe(uint64_t v,uint32_t * pos)664 rte_bsf64_safe(uint64_t v, uint32_t *pos)
665 {
666 	if (v == 0)
667 		return 0;
668 
669 	*pos = rte_bsf64(v);
670 	return 1;
671 }
672 
673 /**
674  * Return the last (most-significant) bit set.
675  *
676  * @note The last (most significant) bit is at position 64.
677  * @note rte_fls_u64(0) = 0, rte_fls_u64(1) = 1,
678  *       rte_fls_u64(0x8000000000000000) = 64
679  *
680  * @param x
681  *     The input parameter.
682  * @return
683  *     The last (most-significant) bit set, or 0 if the input is 0.
684  */
685 static inline int
rte_fls_u64(uint64_t x)686 rte_fls_u64(uint64_t x)
687 {
688 	return (x == 0) ? 0 : 64 - __builtin_clzll(x);
689 }
690 
691 /**
692  * Return the rounded-up log2 of a 64-bit integer.
693  *
694  * @note Contrary to the logarithm mathematical operation,
695  * rte_log2_u64(0) == 0 and not -inf.
696  *
697  * @param v
698  *     The input parameter.
699  * @return
700  *     The rounded-up log2 of the input, or 0 if the input is 0.
701  */
702 static inline uint32_t
rte_log2_u64(uint64_t v)703 rte_log2_u64(uint64_t v)
704 {
705 	if (v == 0)
706 		return 0;
707 	v = rte_align64pow2(v);
708 	/* we checked for v being 0 already, so no undefined behavior */
709 	return rte_bsf64(v);
710 }
711 
712 #ifndef offsetof
713 /** Return the offset of a field in a structure. */
714 #define offsetof(TYPE, MEMBER)  __builtin_offsetof (TYPE, MEMBER)
715 #endif
716 
717 /**
718  * Return pointer to the wrapping struct instance.
719  *
720  * Example:
721  *
722  *  struct wrapper {
723  *      ...
724  *      struct child c;
725  *      ...
726  *  };
727  *
728  *  struct child *x = obtain(...);
729  *  struct wrapper *w = container_of(x, struct wrapper, c);
730  */
731 #ifndef container_of
732 #define container_of(ptr, type, member)	__extension__ ({		\
733 			const typeof(((type *)0)->member) *_ptr = (ptr); \
734 			__rte_unused type *_target_ptr =	\
735 				(type *)(ptr);				\
736 			(type *)(((uintptr_t)_ptr) - offsetof(type, member)); \
737 		})
738 #endif
739 
740 /**
741  * Get the size of a field in a structure.
742  *
743  * @param type
744  *   The type of the structure.
745  * @param field
746  *   The field in the structure.
747  * @return
748  *   The size of the field in the structure, in bytes.
749  */
750 #define RTE_SIZEOF_FIELD(type, field) (sizeof(((type *)0)->field))
751 
752 #define _RTE_STR(x) #x
753 /** Take a macro value and get a string version of it */
754 #define RTE_STR(x) _RTE_STR(x)
755 
756 /**
757  * ISO C helpers to modify format strings using variadic macros.
758  * This is a replacement for the ", ## __VA_ARGS__" GNU extension.
759  * An empty %s argument is appended to avoid a dangling comma.
760  */
761 #define RTE_FMT(fmt, ...) fmt "%.0s", __VA_ARGS__ ""
762 #define RTE_FMT_HEAD(fmt, ...) fmt
763 #define RTE_FMT_TAIL(fmt, ...) __VA_ARGS__
764 
765 /** Mask value of type "tp" for the first "ln" bit set. */
766 #define	RTE_LEN2MASK(ln, tp)	\
767 	((tp)((uint64_t)-1 >> (sizeof(uint64_t) * CHAR_BIT - (ln))))
768 
769 /** Number of elements in the array. */
770 #define	RTE_DIM(a)	(sizeof (a) / sizeof ((a)[0]))
771 
772 /**
773  * Converts a numeric string to the equivalent uint64_t value.
774  * As well as straight number conversion, also recognises the suffixes
775  * k, m and g for kilobytes, megabytes and gigabytes respectively.
776  *
777  * If a negative number is passed in  i.e. a string with the first non-black
778  * character being "-", zero is returned. Zero is also returned in the case of
779  * an error with the strtoull call in the function.
780  *
781  * @param str
782  *     String containing number to convert.
783  * @return
784  *     Number.
785  */
786 #if 0
787 static inline uint64_t
788 rte_str_to_size(const char *str)
789 {
790 	char *endptr;
791 	unsigned long long size;
792 
793 	while (isspace((int)*str))
794 		str++;
795 	if (*str == '-')
796 		return 0;
797 
798 	errno = 0;
799 	size = strtoull(str, &endptr, 0);
800 	if (errno)
801 		return 0;
802 
803 	if (*endptr == ' ')
804 		endptr++; /* allow 1 space gap */
805 
806 	switch (*endptr){
807 	case 'G': case 'g': size *= 1024; /* fall-through */
808 	case 'M': case 'm': size *= 1024; /* fall-through */
809 	case 'K': case 'k': size *= 1024; /* fall-through */
810 	default:
811 		break;
812 	}
813 	return size;
814 }
815 #endif
816 
817 /**
818  * Function to terminate the application immediately, printing an error
819  * message and returning the exit_code back to the shell.
820  *
821  * This function never returns
822  *
823  * @param exit_code
824  *     The exit code to be returned by the application
825  * @param format
826  *     The format string to be used for printing the message. This can include
827  *     printf format characters which will be expanded using any further parameters
828  *     to the function.
829  */
830 __rte_noreturn void
831 rte_exit(int exit_code, const char *format, ...)
832 	__rte_format_printf(2, 3);
833 
834 #ifdef __cplusplus
835 }
836 #endif
837 
838 #endif
839