sparse: define dummy BUILD_BUG_ON definition for sparse
[linux-2.6/libata-dev.git] / include / linux / kernel.h
blob22295244de18d55335326628596b34c8ebbf7019
1 #ifndef _LINUX_KERNEL_H
2 #define _LINUX_KERNEL_H
4 /*
5 * 'kernel.h' contains some often-used function prototypes etc
6 */
7 #define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
8 #define __ALIGN_KERNEL_MASK(x, mask) (((x) + (mask)) & ~(mask))
10 #ifdef __KERNEL__
12 #include <stdarg.h>
13 #include <linux/linkage.h>
14 #include <linux/stddef.h>
15 #include <linux/types.h>
16 #include <linux/compiler.h>
17 #include <linux/bitops.h>
18 #include <linux/log2.h>
19 #include <linux/typecheck.h>
20 #include <linux/printk.h>
21 #include <linux/dynamic_debug.h>
22 #include <asm/byteorder.h>
23 #include <asm/bug.h>
25 #define USHRT_MAX ((u16)(~0U))
26 #define SHRT_MAX ((s16)(USHRT_MAX>>1))
27 #define SHRT_MIN ((s16)(-SHRT_MAX - 1))
28 #define INT_MAX ((int)(~0U>>1))
29 #define INT_MIN (-INT_MAX - 1)
30 #define UINT_MAX (~0U)
31 #define LONG_MAX ((long)(~0UL>>1))
32 #define LONG_MIN (-LONG_MAX - 1)
33 #define ULONG_MAX (~0UL)
34 #define LLONG_MAX ((long long)(~0ULL>>1))
35 #define LLONG_MIN (-LLONG_MAX - 1)
36 #define ULLONG_MAX (~0ULL)
38 #define STACK_MAGIC 0xdeadbeef
40 #define ALIGN(x, a) __ALIGN_KERNEL((x), (a))
41 #define __ALIGN_MASK(x, mask) __ALIGN_KERNEL_MASK((x), (mask))
42 #define PTR_ALIGN(p, a) ((typeof(p))ALIGN((unsigned long)(p), (a)))
43 #define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0)
45 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
48 * This looks more complex than it should be. But we need to
49 * get the type for the ~ right in round_down (it needs to be
50 * as wide as the result!), and we want to evaluate the macro
51 * arguments just once each.
53 #define __round_mask(x, y) ((__typeof__(x))((y)-1))
54 #define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1)
55 #define round_down(x, y) ((x) & ~__round_mask(x, y))
57 #define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))
58 #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
60 /* The `const' in roundup() prevents gcc-3.3 from calling __divdi3 */
61 #define roundup(x, y) ( \
62 { \
63 const typeof(y) __y = y; \
64 (((x) + (__y - 1)) / __y) * __y; \
65 } \
67 #define rounddown(x, y) ( \
68 { \
69 typeof(x) __x = (x); \
70 __x - (__x % (y)); \
71 } \
73 #define DIV_ROUND_CLOSEST(x, divisor)( \
74 { \
75 typeof(divisor) __divisor = divisor; \
76 (((x) + ((__divisor) / 2)) / (__divisor)); \
77 } \
80 #define _RET_IP_ (unsigned long)__builtin_return_address(0)
81 #define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; })
83 #ifdef CONFIG_LBDAF
84 # include <asm/div64.h>
85 # define sector_div(a, b) do_div(a, b)
86 #else
87 # define sector_div(n, b)( \
88 { \
89 int _res; \
90 _res = (n) % (b); \
91 (n) /= (b); \
92 _res; \
93 } \
95 #endif
97 /**
98 * upper_32_bits - return bits 32-63 of a number
99 * @n: the number we're accessing
101 * A basic shift-right of a 64- or 32-bit quantity. Use this to suppress
102 * the "right shift count >= width of type" warning when that quantity is
103 * 32-bits.
105 #define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))
108 * lower_32_bits - return bits 0-31 of a number
109 * @n: the number we're accessing
111 #define lower_32_bits(n) ((u32)(n))
113 struct completion;
114 struct pt_regs;
115 struct user;
117 #ifdef CONFIG_PREEMPT_VOLUNTARY
118 extern int _cond_resched(void);
119 # define might_resched() _cond_resched()
120 #else
121 # define might_resched() do { } while (0)
122 #endif
124 #ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
125 void __might_sleep(const char *file, int line, int preempt_offset);
127 * might_sleep - annotation for functions that can sleep
129 * this macro will print a stack trace if it is executed in an atomic
130 * context (spinlock, irq-handler, ...).
132 * This is a useful debugging help to be able to catch problems early and not
133 * be bitten later when the calling function happens to sleep when it is not
134 * supposed to.
136 # define might_sleep() \
137 do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
138 #else
139 static inline void __might_sleep(const char *file, int line,
140 int preempt_offset) { }
141 # define might_sleep() do { might_resched(); } while (0)
142 #endif
144 #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
147 * abs() handles unsigned and signed longs, ints, shorts and chars. For all
148 * input types abs() returns a signed long.
149 * abs() should not be used for 64-bit types (s64, u64, long long) - use abs64()
150 * for those.
152 #define abs(x) ({ \
153 long ret; \
154 if (sizeof(x) == sizeof(long)) { \
155 long __x = (x); \
156 ret = (__x < 0) ? -__x : __x; \
157 } else { \
158 int __x = (x); \
159 ret = (__x < 0) ? -__x : __x; \
161 ret; \
164 #define abs64(x) ({ \
165 s64 __x = (x); \
166 (__x < 0) ? -__x : __x; \
169 #ifdef CONFIG_PROVE_LOCKING
170 void might_fault(void);
171 #else
172 static inline void might_fault(void)
174 might_sleep();
176 #endif
178 extern struct atomic_notifier_head panic_notifier_list;
179 extern long (*panic_blink)(int state);
180 NORET_TYPE void panic(const char * fmt, ...)
181 __attribute__ ((NORET_AND format (printf, 1, 2))) __cold;
182 extern void oops_enter(void);
183 extern void oops_exit(void);
184 void print_oops_end_marker(void);
185 extern int oops_may_print(void);
186 NORET_TYPE void do_exit(long error_code)
187 ATTRIB_NORET;
188 NORET_TYPE void complete_and_exit(struct completion *, long)
189 ATTRIB_NORET;
191 /* Internal, do not use. */
192 int __must_check _kstrtoul(const char *s, unsigned int base, unsigned long *res);
193 int __must_check _kstrtol(const char *s, unsigned int base, long *res);
195 int __must_check kstrtoull(const char *s, unsigned int base, unsigned long long *res);
196 int __must_check kstrtoll(const char *s, unsigned int base, long long *res);
197 static inline int __must_check kstrtoul(const char *s, unsigned int base, unsigned long *res)
200 * We want to shortcut function call, but
201 * __builtin_types_compatible_p(unsigned long, unsigned long long) = 0.
203 if (sizeof(unsigned long) == sizeof(unsigned long long) &&
204 __alignof__(unsigned long) == __alignof__(unsigned long long))
205 return kstrtoull(s, base, (unsigned long long *)res);
206 else
207 return _kstrtoul(s, base, res);
210 static inline int __must_check kstrtol(const char *s, unsigned int base, long *res)
213 * We want to shortcut function call, but
214 * __builtin_types_compatible_p(long, long long) = 0.
216 if (sizeof(long) == sizeof(long long) &&
217 __alignof__(long) == __alignof__(long long))
218 return kstrtoll(s, base, (long long *)res);
219 else
220 return _kstrtol(s, base, res);
223 int __must_check kstrtouint(const char *s, unsigned int base, unsigned int *res);
224 int __must_check kstrtoint(const char *s, unsigned int base, int *res);
226 static inline int __must_check kstrtou64(const char *s, unsigned int base, u64 *res)
228 return kstrtoull(s, base, res);
231 static inline int __must_check kstrtos64(const char *s, unsigned int base, s64 *res)
233 return kstrtoll(s, base, res);
236 static inline int __must_check kstrtou32(const char *s, unsigned int base, u32 *res)
238 return kstrtouint(s, base, res);
241 static inline int __must_check kstrtos32(const char *s, unsigned int base, s32 *res)
243 return kstrtoint(s, base, res);
246 int __must_check kstrtou16(const char *s, unsigned int base, u16 *res);
247 int __must_check kstrtos16(const char *s, unsigned int base, s16 *res);
248 int __must_check kstrtou8(const char *s, unsigned int base, u8 *res);
249 int __must_check kstrtos8(const char *s, unsigned int base, s8 *res);
251 extern unsigned long simple_strtoul(const char *,char **,unsigned int);
252 extern long simple_strtol(const char *,char **,unsigned int);
253 extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
254 extern long long simple_strtoll(const char *,char **,unsigned int);
255 #define strict_strtoul kstrtoul
256 #define strict_strtol kstrtol
257 #define strict_strtoull kstrtoull
258 #define strict_strtoll kstrtoll
260 extern int sprintf(char * buf, const char * fmt, ...)
261 __attribute__ ((format (printf, 2, 3)));
262 extern int vsprintf(char *buf, const char *, va_list)
263 __attribute__ ((format (printf, 2, 0)));
264 extern int snprintf(char * buf, size_t size, const char * fmt, ...)
265 __attribute__ ((format (printf, 3, 4)));
266 extern int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
267 __attribute__ ((format (printf, 3, 0)));
268 extern int scnprintf(char * buf, size_t size, const char * fmt, ...)
269 __attribute__ ((format (printf, 3, 4)));
270 extern int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
271 __attribute__ ((format (printf, 3, 0)));
272 extern char *kasprintf(gfp_t gfp, const char *fmt, ...)
273 __attribute__ ((format (printf, 2, 3)));
274 extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args);
276 extern int sscanf(const char *, const char *, ...)
277 __attribute__ ((format (scanf, 2, 3)));
278 extern int vsscanf(const char *, const char *, va_list)
279 __attribute__ ((format (scanf, 2, 0)));
281 extern int get_option(char **str, int *pint);
282 extern char *get_options(const char *str, int nints, int *ints);
283 extern unsigned long long memparse(const char *ptr, char **retptr);
285 extern int core_kernel_text(unsigned long addr);
286 extern int core_kernel_data(unsigned long addr);
287 extern int __kernel_text_address(unsigned long addr);
288 extern int kernel_text_address(unsigned long addr);
289 extern int func_ptr_is_kernel_text(void *ptr);
291 struct pid;
292 extern struct pid *session_of_pgrp(struct pid *pgrp);
294 unsigned long int_sqrt(unsigned long);
296 extern void bust_spinlocks(int yes);
297 extern void wake_up_klogd(void);
298 extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */
299 extern int panic_timeout;
300 extern int panic_on_oops;
301 extern int panic_on_unrecovered_nmi;
302 extern int panic_on_io_nmi;
303 extern const char *print_tainted(void);
304 extern void add_taint(unsigned flag);
305 extern int test_taint(unsigned flag);
306 extern unsigned long get_taint(void);
307 extern int root_mountflags;
309 extern bool early_boot_irqs_disabled;
311 /* Values used for system_state */
312 extern enum system_states {
313 SYSTEM_BOOTING,
314 SYSTEM_RUNNING,
315 SYSTEM_HALT,
316 SYSTEM_POWER_OFF,
317 SYSTEM_RESTART,
318 SYSTEM_SUSPEND_DISK,
319 } system_state;
321 #define TAINT_PROPRIETARY_MODULE 0
322 #define TAINT_FORCED_MODULE 1
323 #define TAINT_UNSAFE_SMP 2
324 #define TAINT_FORCED_RMMOD 3
325 #define TAINT_MACHINE_CHECK 4
326 #define TAINT_BAD_PAGE 5
327 #define TAINT_USER 6
328 #define TAINT_DIE 7
329 #define TAINT_OVERRIDDEN_ACPI_TABLE 8
330 #define TAINT_WARN 9
331 #define TAINT_CRAP 10
332 #define TAINT_FIRMWARE_WORKAROUND 11
334 extern const char hex_asc[];
335 #define hex_asc_lo(x) hex_asc[((x) & 0x0f)]
336 #define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4]
338 static inline char *pack_hex_byte(char *buf, u8 byte)
340 *buf++ = hex_asc_hi(byte);
341 *buf++ = hex_asc_lo(byte);
342 return buf;
345 extern int hex_to_bin(char ch);
346 extern void hex2bin(u8 *dst, const char *src, size_t count);
349 * General tracing related utility functions - trace_printk(),
350 * tracing_on/tracing_off and tracing_start()/tracing_stop
352 * Use tracing_on/tracing_off when you want to quickly turn on or off
353 * tracing. It simply enables or disables the recording of the trace events.
354 * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on
355 * file, which gives a means for the kernel and userspace to interact.
356 * Place a tracing_off() in the kernel where you want tracing to end.
357 * From user space, examine the trace, and then echo 1 > tracing_on
358 * to continue tracing.
360 * tracing_stop/tracing_start has slightly more overhead. It is used
361 * by things like suspend to ram where disabling the recording of the
362 * trace is not enough, but tracing must actually stop because things
363 * like calling smp_processor_id() may crash the system.
365 * Most likely, you want to use tracing_on/tracing_off.
367 #ifdef CONFIG_RING_BUFFER
368 void tracing_on(void);
369 void tracing_off(void);
370 /* trace_off_permanent stops recording with no way to bring it back */
371 void tracing_off_permanent(void);
372 int tracing_is_on(void);
373 #else
374 static inline void tracing_on(void) { }
375 static inline void tracing_off(void) { }
376 static inline void tracing_off_permanent(void) { }
377 static inline int tracing_is_on(void) { return 0; }
378 #endif
380 enum ftrace_dump_mode {
381 DUMP_NONE,
382 DUMP_ALL,
383 DUMP_ORIG,
386 #ifdef CONFIG_TRACING
387 extern void tracing_start(void);
388 extern void tracing_stop(void);
389 extern void ftrace_off_permanent(void);
391 static inline void __attribute__ ((format (printf, 1, 2)))
392 ____trace_printk_check_format(const char *fmt, ...)
395 #define __trace_printk_check_format(fmt, args...) \
396 do { \
397 if (0) \
398 ____trace_printk_check_format(fmt, ##args); \
399 } while (0)
402 * trace_printk - printf formatting in the ftrace buffer
403 * @fmt: the printf format for printing
405 * Note: __trace_printk is an internal function for trace_printk and
406 * the @ip is passed in via the trace_printk macro.
408 * This function allows a kernel developer to debug fast path sections
409 * that printk is not appropriate for. By scattering in various
410 * printk like tracing in the code, a developer can quickly see
411 * where problems are occurring.
413 * This is intended as a debugging tool for the developer only.
414 * Please refrain from leaving trace_printks scattered around in
415 * your code.
418 #define trace_printk(fmt, args...) \
419 do { \
420 __trace_printk_check_format(fmt, ##args); \
421 if (__builtin_constant_p(fmt)) { \
422 static const char *trace_printk_fmt \
423 __attribute__((section("__trace_printk_fmt"))) = \
424 __builtin_constant_p(fmt) ? fmt : NULL; \
426 __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \
427 } else \
428 __trace_printk(_THIS_IP_, fmt, ##args); \
429 } while (0)
431 extern int
432 __trace_bprintk(unsigned long ip, const char *fmt, ...)
433 __attribute__ ((format (printf, 2, 3)));
435 extern int
436 __trace_printk(unsigned long ip, const char *fmt, ...)
437 __attribute__ ((format (printf, 2, 3)));
439 extern void trace_dump_stack(void);
442 * The double __builtin_constant_p is because gcc will give us an error
443 * if we try to allocate the static variable to fmt if it is not a
444 * constant. Even with the outer if statement.
446 #define ftrace_vprintk(fmt, vargs) \
447 do { \
448 if (__builtin_constant_p(fmt)) { \
449 static const char *trace_printk_fmt \
450 __attribute__((section("__trace_printk_fmt"))) = \
451 __builtin_constant_p(fmt) ? fmt : NULL; \
453 __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \
454 } else \
455 __ftrace_vprintk(_THIS_IP_, fmt, vargs); \
456 } while (0)
458 extern int
459 __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap);
461 extern int
462 __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap);
464 extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode);
465 #else
466 static inline int
467 trace_printk(const char *fmt, ...) __attribute__ ((format (printf, 1, 2)));
469 static inline void tracing_start(void) { }
470 static inline void tracing_stop(void) { }
471 static inline void ftrace_off_permanent(void) { }
472 static inline void trace_dump_stack(void) { }
473 static inline int
474 trace_printk(const char *fmt, ...)
476 return 0;
478 static inline int
479 ftrace_vprintk(const char *fmt, va_list ap)
481 return 0;
483 static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { }
484 #endif /* CONFIG_TRACING */
487 * min()/max()/clamp() macros that also do
488 * strict type-checking.. See the
489 * "unnecessary" pointer comparison.
491 #define min(x, y) ({ \
492 typeof(x) _min1 = (x); \
493 typeof(y) _min2 = (y); \
494 (void) (&_min1 == &_min2); \
495 _min1 < _min2 ? _min1 : _min2; })
497 #define max(x, y) ({ \
498 typeof(x) _max1 = (x); \
499 typeof(y) _max2 = (y); \
500 (void) (&_max1 == &_max2); \
501 _max1 > _max2 ? _max1 : _max2; })
503 #define min3(x, y, z) ({ \
504 typeof(x) _min1 = (x); \
505 typeof(y) _min2 = (y); \
506 typeof(z) _min3 = (z); \
507 (void) (&_min1 == &_min2); \
508 (void) (&_min1 == &_min3); \
509 _min1 < _min2 ? (_min1 < _min3 ? _min1 : _min3) : \
510 (_min2 < _min3 ? _min2 : _min3); })
512 #define max3(x, y, z) ({ \
513 typeof(x) _max1 = (x); \
514 typeof(y) _max2 = (y); \
515 typeof(z) _max3 = (z); \
516 (void) (&_max1 == &_max2); \
517 (void) (&_max1 == &_max3); \
518 _max1 > _max2 ? (_max1 > _max3 ? _max1 : _max3) : \
519 (_max2 > _max3 ? _max2 : _max3); })
522 * min_not_zero - return the minimum that is _not_ zero, unless both are zero
523 * @x: value1
524 * @y: value2
526 #define min_not_zero(x, y) ({ \
527 typeof(x) __x = (x); \
528 typeof(y) __y = (y); \
529 __x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); })
532 * clamp - return a value clamped to a given range with strict typechecking
533 * @val: current value
534 * @min: minimum allowable value
535 * @max: maximum allowable value
537 * This macro does strict typechecking of min/max to make sure they are of the
538 * same type as val. See the unnecessary pointer comparisons.
540 #define clamp(val, min, max) ({ \
541 typeof(val) __val = (val); \
542 typeof(min) __min = (min); \
543 typeof(max) __max = (max); \
544 (void) (&__val == &__min); \
545 (void) (&__val == &__max); \
546 __val = __val < __min ? __min: __val; \
547 __val > __max ? __max: __val; })
550 * ..and if you can't take the strict
551 * types, you can specify one yourself.
553 * Or not use min/max/clamp at all, of course.
555 #define min_t(type, x, y) ({ \
556 type __min1 = (x); \
557 type __min2 = (y); \
558 __min1 < __min2 ? __min1: __min2; })
560 #define max_t(type, x, y) ({ \
561 type __max1 = (x); \
562 type __max2 = (y); \
563 __max1 > __max2 ? __max1: __max2; })
566 * clamp_t - return a value clamped to a given range using a given type
567 * @type: the type of variable to use
568 * @val: current value
569 * @min: minimum allowable value
570 * @max: maximum allowable value
572 * This macro does no typechecking and uses temporary variables of type
573 * 'type' to make all the comparisons.
575 #define clamp_t(type, val, min, max) ({ \
576 type __val = (val); \
577 type __min = (min); \
578 type __max = (max); \
579 __val = __val < __min ? __min: __val; \
580 __val > __max ? __max: __val; })
583 * clamp_val - return a value clamped to a given range using val's type
584 * @val: current value
585 * @min: minimum allowable value
586 * @max: maximum allowable value
588 * This macro does no typechecking and uses temporary variables of whatever
589 * type the input argument 'val' is. This is useful when val is an unsigned
590 * type and min and max are literals that will otherwise be assigned a signed
591 * integer type.
593 #define clamp_val(val, min, max) ({ \
594 typeof(val) __val = (val); \
595 typeof(val) __min = (min); \
596 typeof(val) __max = (max); \
597 __val = __val < __min ? __min: __val; \
598 __val > __max ? __max: __val; })
602 * swap - swap value of @a and @b
604 #define swap(a, b) \
605 do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0)
608 * container_of - cast a member of a structure out to the containing structure
609 * @ptr: the pointer to the member.
610 * @type: the type of the container struct this is embedded in.
611 * @member: the name of the member within the struct.
614 #define container_of(ptr, type, member) ({ \
615 const typeof( ((type *)0)->member ) *__mptr = (ptr); \
616 (type *)( (char *)__mptr - offsetof(type,member) );})
618 struct sysinfo;
619 extern int do_sysinfo(struct sysinfo *info);
621 #endif /* __KERNEL__ */
623 #define SI_LOAD_SHIFT 16
624 struct sysinfo {
625 long uptime; /* Seconds since boot */
626 unsigned long loads[3]; /* 1, 5, and 15 minute load averages */
627 unsigned long totalram; /* Total usable main memory size */
628 unsigned long freeram; /* Available memory size */
629 unsigned long sharedram; /* Amount of shared memory */
630 unsigned long bufferram; /* Memory used by buffers */
631 unsigned long totalswap; /* Total swap space size */
632 unsigned long freeswap; /* swap space still available */
633 unsigned short procs; /* Number of current processes */
634 unsigned short pad; /* explicit padding for m68k */
635 unsigned long totalhigh; /* Total high memory size */
636 unsigned long freehigh; /* Available high memory size */
637 unsigned int mem_unit; /* Memory unit size in bytes */
638 char _f[20-2*sizeof(long)-sizeof(int)]; /* Padding: libc5 uses this.. */
641 #ifdef __CHECKER__
642 #define BUILD_BUG_ON_NOT_POWER_OF_2(n)
643 #define BUILD_BUG_ON_ZERO(e)
644 #define BUILD_BUG_ON_NULL(e)
645 #define BUILD_BUG_ON(condition)
646 #else /* __CHECKER__ */
648 /* Force a compilation error if a constant expression is not a power of 2 */
649 #define BUILD_BUG_ON_NOT_POWER_OF_2(n) \
650 BUILD_BUG_ON((n) == 0 || (((n) & ((n) - 1)) != 0))
652 /* Force a compilation error if condition is true, but also produce a
653 result (of value 0 and type size_t), so the expression can be used
654 e.g. in a structure initializer (or where-ever else comma expressions
655 aren't permitted). */
656 #define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); }))
657 #define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); }))
660 * BUILD_BUG_ON - break compile if a condition is true.
661 * @condition: the condition which the compiler should know is false.
663 * If you have some code which relies on certain constants being equal, or
664 * other compile-time-evaluated condition, you should use BUILD_BUG_ON to
665 * detect if someone changes it.
667 * The implementation uses gcc's reluctance to create a negative array, but
668 * gcc (as of 4.4) only emits that error for obvious cases (eg. not arguments
669 * to inline functions). So as a fallback we use the optimizer; if it can't
670 * prove the condition is false, it will cause a link error on the undefined
671 * "__build_bug_on_failed". This error message can be harder to track down
672 * though, hence the two different methods.
674 #ifndef __OPTIMIZE__
675 #define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
676 #else
677 extern int __build_bug_on_failed;
678 #define BUILD_BUG_ON(condition) \
679 do { \
680 ((void)sizeof(char[1 - 2*!!(condition)])); \
681 if (condition) __build_bug_on_failed = 1; \
682 } while(0)
683 #endif
684 #endif /* __CHECKER__ */
686 /* Trap pasters of __FUNCTION__ at compile-time */
687 #define __FUNCTION__ (__func__)
689 /* This helps us to avoid #ifdef CONFIG_NUMA */
690 #ifdef CONFIG_NUMA
691 #define NUMA_BUILD 1
692 #else
693 #define NUMA_BUILD 0
694 #endif
696 /* This helps us avoid #ifdef CONFIG_COMPACTION */
697 #ifdef CONFIG_COMPACTION
698 #define COMPACTION_BUILD 1
699 #else
700 #define COMPACTION_BUILD 0
701 #endif
703 /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
704 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
705 # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD
706 #endif
708 #endif