1 #ifndef _LINUX_KERNEL_H
2 #define _LINUX_KERNEL_H
5 * 'kernel.h' contains some often-used function prototypes etc
7 #define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
8 #define __ALIGN_KERNEL_MASK(x, mask) (((x) + (mask)) & ~(mask))
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>
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) ( \
63 const typeof(y) __y = y; \
64 (((x) + (__y - 1)) / __y) * __y; \
67 #define rounddown(x, y) ( \
69 typeof(x) __x = (x); \
73 #define DIV_ROUND_CLOSEST(x, divisor)( \
75 typeof(divisor) __divisor = divisor; \
76 (((x) + ((__divisor) / 2)) / (__divisor)); \
81 * Multiplies an integer by a fraction, while avoiding unnecessary
82 * overflow or loss of precision.
84 #define mult_frac(x, numer, denom)( \
86 typeof(x) quot = (x) / (denom); \
87 typeof(x) rem = (x) % (denom); \
88 (quot * (numer)) + ((rem * (numer)) / (denom)); \
93 #define _RET_IP_ (unsigned long)__builtin_return_address(0)
94 #define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; })
97 # include <asm/div64.h>
98 # define sector_div(a, b) do_div(a, b)
100 # define sector_div(n, b)( \
111 * upper_32_bits - return bits 32-63 of a number
112 * @n: the number we're accessing
114 * A basic shift-right of a 64- or 32-bit quantity. Use this to suppress
115 * the "right shift count >= width of type" warning when that quantity is
118 #define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))
121 * lower_32_bits - return bits 0-31 of a number
122 * @n: the number we're accessing
124 #define lower_32_bits(n) ((u32)(n))
130 /* cannot bring in linux/rcupdate.h at this point */
132 extern void rcu_note_might_resched(void);
134 #define rcu_note_might_resched()
137 #ifdef CONFIG_PREEMPT_VOLUNTARY
138 extern int _cond_resched(void);
139 # define might_resched() do { _cond_resched(); rcu_note_might_resched(); } while (0)
141 # define might_resched() do { rcu_note_might_resched(); } while (0)
144 #ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
145 void __might_sleep(const char *file
, int line
, int preempt_offset
);
147 * might_sleep - annotation for functions that can sleep
149 * this macro will print a stack trace if it is executed in an atomic
150 * context (spinlock, irq-handler, ...).
152 * This is a useful debugging help to be able to catch problems early and not
153 * be bitten later when the calling function happens to sleep when it is not
156 # define might_sleep() \
157 do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
159 static inline void __might_sleep(const char *file
, int line
,
160 int preempt_offset
) { }
161 # define might_sleep() do { might_resched(); } while (0)
164 #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
167 * abs() handles unsigned and signed longs, ints, shorts and chars. For all
168 * input types abs() returns a signed long.
169 * abs() should not be used for 64-bit types (s64, u64, long long) - use abs64()
174 if (sizeof(x) == sizeof(long)) { \
176 ret = (__x < 0) ? -__x : __x; \
179 ret = (__x < 0) ? -__x : __x; \
184 #define abs64(x) ({ \
186 (__x < 0) ? -__x : __x; \
189 #ifdef CONFIG_PROVE_LOCKING
190 void might_fault(void);
192 static inline void might_fault(void)
198 extern struct atomic_notifier_head panic_notifier_list
;
199 extern long (*panic_blink
)(int state
);
200 NORET_TYPE
void panic(const char * fmt
, ...)
201 __attribute__ ((NORET_AND
format (printf
, 1, 2))) __cold
;
202 extern void oops_enter(void);
203 extern void oops_exit(void);
204 void print_oops_end_marker(void);
205 extern int oops_may_print(void);
206 NORET_TYPE
void do_exit(long error_code
)
208 NORET_TYPE
void complete_and_exit(struct completion
*, long)
211 /* Internal, do not use. */
212 int __must_check
_kstrtoul(const char *s
, unsigned int base
, unsigned long *res
);
213 int __must_check
_kstrtol(const char *s
, unsigned int base
, long *res
);
215 int __must_check
kstrtoull(const char *s
, unsigned int base
, unsigned long long *res
);
216 int __must_check
kstrtoll(const char *s
, unsigned int base
, long long *res
);
217 static inline int __must_check
kstrtoul(const char *s
, unsigned int base
, unsigned long *res
)
220 * We want to shortcut function call, but
221 * __builtin_types_compatible_p(unsigned long, unsigned long long) = 0.
223 if (sizeof(unsigned long) == sizeof(unsigned long long) &&
224 __alignof__(unsigned long) == __alignof__(unsigned long long))
225 return kstrtoull(s
, base
, (unsigned long long *)res
);
227 return _kstrtoul(s
, base
, res
);
230 static inline int __must_check
kstrtol(const char *s
, unsigned int base
, long *res
)
233 * We want to shortcut function call, but
234 * __builtin_types_compatible_p(long, long long) = 0.
236 if (sizeof(long) == sizeof(long long) &&
237 __alignof__(long) == __alignof__(long long))
238 return kstrtoll(s
, base
, (long long *)res
);
240 return _kstrtol(s
, base
, res
);
243 int __must_check
kstrtouint(const char *s
, unsigned int base
, unsigned int *res
);
244 int __must_check
kstrtoint(const char *s
, unsigned int base
, int *res
);
246 static inline int __must_check
kstrtou64(const char *s
, unsigned int base
, u64
*res
)
248 return kstrtoull(s
, base
, res
);
251 static inline int __must_check
kstrtos64(const char *s
, unsigned int base
, s64
*res
)
253 return kstrtoll(s
, base
, res
);
256 static inline int __must_check
kstrtou32(const char *s
, unsigned int base
, u32
*res
)
258 return kstrtouint(s
, base
, res
);
261 static inline int __must_check
kstrtos32(const char *s
, unsigned int base
, s32
*res
)
263 return kstrtoint(s
, base
, res
);
266 int __must_check
kstrtou16(const char *s
, unsigned int base
, u16
*res
);
267 int __must_check
kstrtos16(const char *s
, unsigned int base
, s16
*res
);
268 int __must_check
kstrtou8(const char *s
, unsigned int base
, u8
*res
);
269 int __must_check
kstrtos8(const char *s
, unsigned int base
, s8
*res
);
271 int __must_check
kstrtoull_from_user(const char __user
*s
, size_t count
, unsigned int base
, unsigned long long *res
);
272 int __must_check
kstrtoll_from_user(const char __user
*s
, size_t count
, unsigned int base
, long long *res
);
273 int __must_check
kstrtoul_from_user(const char __user
*s
, size_t count
, unsigned int base
, unsigned long *res
);
274 int __must_check
kstrtol_from_user(const char __user
*s
, size_t count
, unsigned int base
, long *res
);
275 int __must_check
kstrtouint_from_user(const char __user
*s
, size_t count
, unsigned int base
, unsigned int *res
);
276 int __must_check
kstrtoint_from_user(const char __user
*s
, size_t count
, unsigned int base
, int *res
);
277 int __must_check
kstrtou16_from_user(const char __user
*s
, size_t count
, unsigned int base
, u16
*res
);
278 int __must_check
kstrtos16_from_user(const char __user
*s
, size_t count
, unsigned int base
, s16
*res
);
279 int __must_check
kstrtou8_from_user(const char __user
*s
, size_t count
, unsigned int base
, u8
*res
);
280 int __must_check
kstrtos8_from_user(const char __user
*s
, size_t count
, unsigned int base
, s8
*res
);
282 static inline int __must_check
kstrtou64_from_user(const char __user
*s
, size_t count
, unsigned int base
, u64
*res
)
284 return kstrtoull_from_user(s
, count
, base
, res
);
287 static inline int __must_check
kstrtos64_from_user(const char __user
*s
, size_t count
, unsigned int base
, s64
*res
)
289 return kstrtoll_from_user(s
, count
, base
, res
);
292 static inline int __must_check
kstrtou32_from_user(const char __user
*s
, size_t count
, unsigned int base
, u32
*res
)
294 return kstrtouint_from_user(s
, count
, base
, res
);
297 static inline int __must_check
kstrtos32_from_user(const char __user
*s
, size_t count
, unsigned int base
, s32
*res
)
299 return kstrtoint_from_user(s
, count
, base
, res
);
302 extern unsigned long simple_strtoul(const char *,char **,unsigned int);
303 extern long simple_strtol(const char *,char **,unsigned int);
304 extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
305 extern long long simple_strtoll(const char *,char **,unsigned int);
306 #define strict_strtoul kstrtoul
307 #define strict_strtol kstrtol
308 #define strict_strtoull kstrtoull
309 #define strict_strtoll kstrtoll
311 extern int sprintf(char * buf
, const char * fmt
, ...)
312 __attribute__ ((format (printf
, 2, 3)));
313 extern int vsprintf(char *buf
, const char *, va_list)
314 __attribute__ ((format (printf
, 2, 0)));
315 extern int snprintf(char * buf
, size_t size
, const char * fmt
, ...)
316 __attribute__ ((format (printf
, 3, 4)));
317 extern int vsnprintf(char *buf
, size_t size
, const char *fmt
, va_list args
)
318 __attribute__ ((format (printf
, 3, 0)));
319 extern int scnprintf(char * buf
, size_t size
, const char * fmt
, ...)
320 __attribute__ ((format (printf
, 3, 4)));
321 extern int vscnprintf(char *buf
, size_t size
, const char *fmt
, va_list args
)
322 __attribute__ ((format (printf
, 3, 0)));
323 extern char *kasprintf(gfp_t gfp
, const char *fmt
, ...)
324 __attribute__ ((format (printf
, 2, 3)));
325 extern char *kvasprintf(gfp_t gfp
, const char *fmt
, va_list args
);
327 extern int sscanf(const char *, const char *, ...)
328 __attribute__ ((format (scanf
, 2, 3)));
329 extern int vsscanf(const char *, const char *, va_list)
330 __attribute__ ((format (scanf
, 2, 0)));
332 extern int get_option(char **str
, int *pint
);
333 extern char *get_options(const char *str
, int nints
, int *ints
);
334 extern unsigned long long memparse(const char *ptr
, char **retptr
);
336 extern int core_kernel_text(unsigned long addr
);
337 extern int core_kernel_data(unsigned long addr
);
338 extern int __kernel_text_address(unsigned long addr
);
339 extern int kernel_text_address(unsigned long addr
);
340 extern int func_ptr_is_kernel_text(void *ptr
);
343 extern struct pid
*session_of_pgrp(struct pid
*pgrp
);
345 unsigned long int_sqrt(unsigned long);
347 extern void bust_spinlocks(int yes
);
348 extern void wake_up_klogd(void);
349 extern int oops_in_progress
; /* If set, an oops, panic(), BUG() or die() is in progress */
350 extern int panic_timeout
;
351 extern int panic_on_oops
;
352 extern int panic_on_unrecovered_nmi
;
353 extern int panic_on_io_nmi
;
354 extern const char *print_tainted(void);
355 extern void add_taint(unsigned flag
);
356 extern int test_taint(unsigned flag
);
357 extern unsigned long get_taint(void);
358 extern int root_mountflags
;
360 extern bool early_boot_irqs_disabled
;
362 /* Values used for system_state */
363 extern enum system_states
{
372 #define TAINT_PROPRIETARY_MODULE 0
373 #define TAINT_FORCED_MODULE 1
374 #define TAINT_UNSAFE_SMP 2
375 #define TAINT_FORCED_RMMOD 3
376 #define TAINT_MACHINE_CHECK 4
377 #define TAINT_BAD_PAGE 5
380 #define TAINT_OVERRIDDEN_ACPI_TABLE 8
382 #define TAINT_CRAP 10
383 #define TAINT_FIRMWARE_WORKAROUND 11
385 extern const char hex_asc
[];
386 #define hex_asc_lo(x) hex_asc[((x) & 0x0f)]
387 #define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4]
389 static inline char *pack_hex_byte(char *buf
, u8 byte
)
391 *buf
++ = hex_asc_hi(byte
);
392 *buf
++ = hex_asc_lo(byte
);
396 extern int hex_to_bin(char ch
);
397 extern void hex2bin(u8
*dst
, const char *src
, size_t count
);
400 * General tracing related utility functions - trace_printk(),
401 * tracing_on/tracing_off and tracing_start()/tracing_stop
403 * Use tracing_on/tracing_off when you want to quickly turn on or off
404 * tracing. It simply enables or disables the recording of the trace events.
405 * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on
406 * file, which gives a means for the kernel and userspace to interact.
407 * Place a tracing_off() in the kernel where you want tracing to end.
408 * From user space, examine the trace, and then echo 1 > tracing_on
409 * to continue tracing.
411 * tracing_stop/tracing_start has slightly more overhead. It is used
412 * by things like suspend to ram where disabling the recording of the
413 * trace is not enough, but tracing must actually stop because things
414 * like calling smp_processor_id() may crash the system.
416 * Most likely, you want to use tracing_on/tracing_off.
418 #ifdef CONFIG_RING_BUFFER
419 void tracing_on(void);
420 void tracing_off(void);
421 /* trace_off_permanent stops recording with no way to bring it back */
422 void tracing_off_permanent(void);
423 int tracing_is_on(void);
425 static inline void tracing_on(void) { }
426 static inline void tracing_off(void) { }
427 static inline void tracing_off_permanent(void) { }
428 static inline int tracing_is_on(void) { return 0; }
431 enum ftrace_dump_mode
{
437 #ifdef CONFIG_TRACING
438 extern void tracing_start(void);
439 extern void tracing_stop(void);
440 extern void ftrace_off_permanent(void);
442 static inline void __attribute__ ((format (printf
, 1, 2)))
443 ____trace_printk_check_format(const char *fmt
, ...)
446 #define __trace_printk_check_format(fmt, args...) \
449 ____trace_printk_check_format(fmt, ##args); \
453 * trace_printk - printf formatting in the ftrace buffer
454 * @fmt: the printf format for printing
456 * Note: __trace_printk is an internal function for trace_printk and
457 * the @ip is passed in via the trace_printk macro.
459 * This function allows a kernel developer to debug fast path sections
460 * that printk is not appropriate for. By scattering in various
461 * printk like tracing in the code, a developer can quickly see
462 * where problems are occurring.
464 * This is intended as a debugging tool for the developer only.
465 * Please refrain from leaving trace_printks scattered around in
469 #define trace_printk(fmt, args...) \
471 __trace_printk_check_format(fmt, ##args); \
472 if (__builtin_constant_p(fmt)) { \
473 static const char *trace_printk_fmt \
474 __attribute__((section("__trace_printk_fmt"))) = \
475 __builtin_constant_p(fmt) ? fmt : NULL; \
477 __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \
479 __trace_printk(_THIS_IP_, fmt, ##args); \
483 __trace_bprintk(unsigned long ip
, const char *fmt
, ...)
484 __attribute__ ((format (printf
, 2, 3)));
487 __trace_printk(unsigned long ip
, const char *fmt
, ...)
488 __attribute__ ((format (printf
, 2, 3)));
490 extern void trace_dump_stack(void);
493 * The double __builtin_constant_p is because gcc will give us an error
494 * if we try to allocate the static variable to fmt if it is not a
495 * constant. Even with the outer if statement.
497 #define ftrace_vprintk(fmt, vargs) \
499 if (__builtin_constant_p(fmt)) { \
500 static const char *trace_printk_fmt \
501 __attribute__((section("__trace_printk_fmt"))) = \
502 __builtin_constant_p(fmt) ? fmt : NULL; \
504 __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \
506 __ftrace_vprintk(_THIS_IP_, fmt, vargs); \
510 __ftrace_vbprintk(unsigned long ip
, const char *fmt
, va_list ap
);
513 __ftrace_vprintk(unsigned long ip
, const char *fmt
, va_list ap
);
515 extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode
);
518 trace_printk(const char *fmt
, ...) __attribute__ ((format (printf
, 1, 2)));
520 static inline void tracing_start(void) { }
521 static inline void tracing_stop(void) { }
522 static inline void ftrace_off_permanent(void) { }
523 static inline void trace_dump_stack(void) { }
525 trace_printk(const char *fmt
, ...)
530 ftrace_vprintk(const char *fmt
, va_list ap
)
534 static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode
) { }
535 #endif /* CONFIG_TRACING */
538 * min()/max()/clamp() macros that also do
539 * strict type-checking.. See the
540 * "unnecessary" pointer comparison.
542 #define min(x, y) ({ \
543 typeof(x) _min1 = (x); \
544 typeof(y) _min2 = (y); \
545 (void) (&_min1 == &_min2); \
546 _min1 < _min2 ? _min1 : _min2; })
548 #define max(x, y) ({ \
549 typeof(x) _max1 = (x); \
550 typeof(y) _max2 = (y); \
551 (void) (&_max1 == &_max2); \
552 _max1 > _max2 ? _max1 : _max2; })
554 #define min3(x, y, z) ({ \
555 typeof(x) _min1 = (x); \
556 typeof(y) _min2 = (y); \
557 typeof(z) _min3 = (z); \
558 (void) (&_min1 == &_min2); \
559 (void) (&_min1 == &_min3); \
560 _min1 < _min2 ? (_min1 < _min3 ? _min1 : _min3) : \
561 (_min2 < _min3 ? _min2 : _min3); })
563 #define max3(x, y, z) ({ \
564 typeof(x) _max1 = (x); \
565 typeof(y) _max2 = (y); \
566 typeof(z) _max3 = (z); \
567 (void) (&_max1 == &_max2); \
568 (void) (&_max1 == &_max3); \
569 _max1 > _max2 ? (_max1 > _max3 ? _max1 : _max3) : \
570 (_max2 > _max3 ? _max2 : _max3); })
573 * min_not_zero - return the minimum that is _not_ zero, unless both are zero
577 #define min_not_zero(x, y) ({ \
578 typeof(x) __x = (x); \
579 typeof(y) __y = (y); \
580 __x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); })
583 * clamp - return a value clamped to a given range with strict typechecking
584 * @val: current value
585 * @min: minimum allowable value
586 * @max: maximum allowable value
588 * This macro does strict typechecking of min/max to make sure they are of the
589 * same type as val. See the unnecessary pointer comparisons.
591 #define clamp(val, min, max) ({ \
592 typeof(val) __val = (val); \
593 typeof(min) __min = (min); \
594 typeof(max) __max = (max); \
595 (void) (&__val == &__min); \
596 (void) (&__val == &__max); \
597 __val = __val < __min ? __min: __val; \
598 __val > __max ? __max: __val; })
601 * ..and if you can't take the strict
602 * types, you can specify one yourself.
604 * Or not use min/max/clamp at all, of course.
606 #define min_t(type, x, y) ({ \
609 __min1 < __min2 ? __min1: __min2; })
611 #define max_t(type, x, y) ({ \
614 __max1 > __max2 ? __max1: __max2; })
617 * clamp_t - return a value clamped to a given range using a given type
618 * @type: the type of variable to use
619 * @val: current value
620 * @min: minimum allowable value
621 * @max: maximum allowable value
623 * This macro does no typechecking and uses temporary variables of type
624 * 'type' to make all the comparisons.
626 #define clamp_t(type, val, min, max) ({ \
627 type __val = (val); \
628 type __min = (min); \
629 type __max = (max); \
630 __val = __val < __min ? __min: __val; \
631 __val > __max ? __max: __val; })
634 * clamp_val - return a value clamped to a given range using val's type
635 * @val: current value
636 * @min: minimum allowable value
637 * @max: maximum allowable value
639 * This macro does no typechecking and uses temporary variables of whatever
640 * type the input argument 'val' is. This is useful when val is an unsigned
641 * type and min and max are literals that will otherwise be assigned a signed
644 #define clamp_val(val, min, max) ({ \
645 typeof(val) __val = (val); \
646 typeof(val) __min = (min); \
647 typeof(val) __max = (max); \
648 __val = __val < __min ? __min: __val; \
649 __val > __max ? __max: __val; })
653 * swap - swap value of @a and @b
656 do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0)
659 * container_of - cast a member of a structure out to the containing structure
660 * @ptr: the pointer to the member.
661 * @type: the type of the container struct this is embedded in.
662 * @member: the name of the member within the struct.
665 #define container_of(ptr, type, member) ({ \
666 const typeof( ((type *)0)->member ) *__mptr = (ptr); \
667 (type *)( (char *)__mptr - offsetof(type,member) );})
670 extern int do_sysinfo(struct sysinfo
*info
);
672 #endif /* __KERNEL__ */
674 #define SI_LOAD_SHIFT 16
676 long uptime
; /* Seconds since boot */
677 unsigned long loads
[3]; /* 1, 5, and 15 minute load averages */
678 unsigned long totalram
; /* Total usable main memory size */
679 unsigned long freeram
; /* Available memory size */
680 unsigned long sharedram
; /* Amount of shared memory */
681 unsigned long bufferram
; /* Memory used by buffers */
682 unsigned long totalswap
; /* Total swap space size */
683 unsigned long freeswap
; /* swap space still available */
684 unsigned short procs
; /* Number of current processes */
685 unsigned short pad
; /* explicit padding for m68k */
686 unsigned long totalhigh
; /* Total high memory size */
687 unsigned long freehigh
; /* Available high memory size */
688 unsigned int mem_unit
; /* Memory unit size in bytes */
689 char _f
[20-2*sizeof(long)-sizeof(int)]; /* Padding: libc5 uses this.. */
693 #define BUILD_BUG_ON_NOT_POWER_OF_2(n)
694 #define BUILD_BUG_ON_ZERO(e) (0)
695 #define BUILD_BUG_ON_NULL(e) ((void*)0)
696 #define BUILD_BUG_ON(condition)
697 #else /* __CHECKER__ */
699 /* Force a compilation error if a constant expression is not a power of 2 */
700 #define BUILD_BUG_ON_NOT_POWER_OF_2(n) \
701 BUILD_BUG_ON((n) == 0 || (((n) & ((n) - 1)) != 0))
703 /* Force a compilation error if condition is true, but also produce a
704 result (of value 0 and type size_t), so the expression can be used
705 e.g. in a structure initializer (or where-ever else comma expressions
706 aren't permitted). */
707 #define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); }))
708 #define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); }))
711 * BUILD_BUG_ON - break compile if a condition is true.
712 * @condition: the condition which the compiler should know is false.
714 * If you have some code which relies on certain constants being equal, or
715 * other compile-time-evaluated condition, you should use BUILD_BUG_ON to
716 * detect if someone changes it.
718 * The implementation uses gcc's reluctance to create a negative array, but
719 * gcc (as of 4.4) only emits that error for obvious cases (eg. not arguments
720 * to inline functions). So as a fallback we use the optimizer; if it can't
721 * prove the condition is false, it will cause a link error on the undefined
722 * "__build_bug_on_failed". This error message can be harder to track down
723 * though, hence the two different methods.
726 #define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
728 extern int __build_bug_on_failed
;
729 #define BUILD_BUG_ON(condition) \
731 ((void)sizeof(char[1 - 2*!!(condition)])); \
732 if (condition) __build_bug_on_failed = 1; \
735 #endif /* __CHECKER__ */
737 /* Trap pasters of __FUNCTION__ at compile-time */
738 #define __FUNCTION__ (__func__)
740 /* This helps us to avoid #ifdef CONFIG_NUMA */
747 /* This helps us avoid #ifdef CONFIG_COMPACTION */
748 #ifdef CONFIG_COMPACTION
749 #define COMPACTION_BUILD 1
751 #define COMPACTION_BUILD 0
754 /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
755 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
756 # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD
759 /* To identify board information in panic logs, set this */
760 extern char *mach_panic_string
;