[media] cec: update log_addr[] before finishing configuration
[linux-2.6/btrfs-unstable.git] / include / linux / kernel.h
blobbc6ed52a39b967898c6e2f2814e23fbd6f2a3332
1 #ifndef _LINUX_KERNEL_H
2 #define _LINUX_KERNEL_H
5 #include <stdarg.h>
6 #include <linux/linkage.h>
7 #include <linux/stddef.h>
8 #include <linux/types.h>
9 #include <linux/compiler.h>
10 #include <linux/bitops.h>
11 #include <linux/log2.h>
12 #include <linux/typecheck.h>
13 #include <linux/printk.h>
14 #include <asm/byteorder.h>
15 #include <uapi/linux/kernel.h>
17 #define USHRT_MAX ((u16)(~0U))
18 #define SHRT_MAX ((s16)(USHRT_MAX>>1))
19 #define SHRT_MIN ((s16)(-SHRT_MAX - 1))
20 #define INT_MAX ((int)(~0U>>1))
21 #define INT_MIN (-INT_MAX - 1)
22 #define UINT_MAX (~0U)
23 #define LONG_MAX ((long)(~0UL>>1))
24 #define LONG_MIN (-LONG_MAX - 1)
25 #define ULONG_MAX (~0UL)
26 #define LLONG_MAX ((long long)(~0ULL>>1))
27 #define LLONG_MIN (-LLONG_MAX - 1)
28 #define ULLONG_MAX (~0ULL)
29 #define SIZE_MAX (~(size_t)0)
31 #define U8_MAX ((u8)~0U)
32 #define S8_MAX ((s8)(U8_MAX>>1))
33 #define S8_MIN ((s8)(-S8_MAX - 1))
34 #define U16_MAX ((u16)~0U)
35 #define S16_MAX ((s16)(U16_MAX>>1))
36 #define S16_MIN ((s16)(-S16_MAX - 1))
37 #define U32_MAX ((u32)~0U)
38 #define S32_MAX ((s32)(U32_MAX>>1))
39 #define S32_MIN ((s32)(-S32_MAX - 1))
40 #define U64_MAX ((u64)~0ULL)
41 #define S64_MAX ((s64)(U64_MAX>>1))
42 #define S64_MIN ((s64)(-S64_MAX - 1))
44 #define STACK_MAGIC 0xdeadbeef
46 #define REPEAT_BYTE(x) ((~0ul / 0xff) * (x))
48 #define ALIGN(x, a) __ALIGN_KERNEL((x), (a))
49 #define __ALIGN_MASK(x, mask) __ALIGN_KERNEL_MASK((x), (mask))
50 #define PTR_ALIGN(p, a) ((typeof(p))ALIGN((unsigned long)(p), (a)))
51 #define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0)
53 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
55 #define u64_to_user_ptr(x) ( \
56 { \
57 typecheck(u64, x); \
58 (void __user *)(uintptr_t)x; \
59 } \
63 * This looks more complex than it should be. But we need to
64 * get the type for the ~ right in round_down (it needs to be
65 * as wide as the result!), and we want to evaluate the macro
66 * arguments just once each.
68 #define __round_mask(x, y) ((__typeof__(x))((y)-1))
69 #define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1)
70 #define round_down(x, y) ((x) & ~__round_mask(x, y))
72 #define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))
73 #define DIV_ROUND_UP __KERNEL_DIV_ROUND_UP
74 #define DIV_ROUND_UP_ULL(ll,d) \
75 ({ unsigned long long _tmp = (ll)+(d)-1; do_div(_tmp, d); _tmp; })
77 #if BITS_PER_LONG == 32
78 # define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP_ULL(ll, d)
79 #else
80 # define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP(ll,d)
81 #endif
83 /* The `const' in roundup() prevents gcc-3.3 from calling __divdi3 */
84 #define roundup(x, y) ( \
85 { \
86 const typeof(y) __y = y; \
87 (((x) + (__y - 1)) / __y) * __y; \
88 } \
90 #define rounddown(x, y) ( \
91 { \
92 typeof(x) __x = (x); \
93 __x - (__x % (y)); \
94 } \
98 * Divide positive or negative dividend by positive divisor and round
99 * to closest integer. Result is undefined for negative divisors and
100 * for negative dividends if the divisor variable type is unsigned.
102 #define DIV_ROUND_CLOSEST(x, divisor)( \
104 typeof(x) __x = x; \
105 typeof(divisor) __d = divisor; \
106 (((typeof(x))-1) > 0 || \
107 ((typeof(divisor))-1) > 0 || (__x) > 0) ? \
108 (((__x) + ((__d) / 2)) / (__d)) : \
109 (((__x) - ((__d) / 2)) / (__d)); \
113 * Same as above but for u64 dividends. divisor must be a 32-bit
114 * number.
116 #define DIV_ROUND_CLOSEST_ULL(x, divisor)( \
118 typeof(divisor) __d = divisor; \
119 unsigned long long _tmp = (x) + (__d) / 2; \
120 do_div(_tmp, __d); \
121 _tmp; \
126 * Multiplies an integer by a fraction, while avoiding unnecessary
127 * overflow or loss of precision.
129 #define mult_frac(x, numer, denom)( \
131 typeof(x) quot = (x) / (denom); \
132 typeof(x) rem = (x) % (denom); \
133 (quot * (numer)) + ((rem * (numer)) / (denom)); \
138 #define _RET_IP_ (unsigned long)__builtin_return_address(0)
139 #define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; })
141 #ifdef CONFIG_LBDAF
142 # include <asm/div64.h>
143 # define sector_div(a, b) do_div(a, b)
144 #else
145 # define sector_div(n, b)( \
147 int _res; \
148 _res = (n) % (b); \
149 (n) /= (b); \
150 _res; \
153 #endif
156 * upper_32_bits - return bits 32-63 of a number
157 * @n: the number we're accessing
159 * A basic shift-right of a 64- or 32-bit quantity. Use this to suppress
160 * the "right shift count >= width of type" warning when that quantity is
161 * 32-bits.
163 #define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))
166 * lower_32_bits - return bits 0-31 of a number
167 * @n: the number we're accessing
169 #define lower_32_bits(n) ((u32)(n))
171 struct completion;
172 struct pt_regs;
173 struct user;
175 #ifdef CONFIG_PREEMPT_VOLUNTARY
176 extern int _cond_resched(void);
177 # define might_resched() _cond_resched()
178 #else
179 # define might_resched() do { } while (0)
180 #endif
182 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
183 void ___might_sleep(const char *file, int line, int preempt_offset);
184 void __might_sleep(const char *file, int line, int preempt_offset);
186 * might_sleep - annotation for functions that can sleep
188 * this macro will print a stack trace if it is executed in an atomic
189 * context (spinlock, irq-handler, ...).
191 * This is a useful debugging help to be able to catch problems early and not
192 * be bitten later when the calling function happens to sleep when it is not
193 * supposed to.
195 # define might_sleep() \
196 do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
197 # define sched_annotate_sleep() (current->task_state_change = 0)
198 #else
199 static inline void ___might_sleep(const char *file, int line,
200 int preempt_offset) { }
201 static inline void __might_sleep(const char *file, int line,
202 int preempt_offset) { }
203 # define might_sleep() do { might_resched(); } while (0)
204 # define sched_annotate_sleep() do { } while (0)
205 #endif
207 #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
210 * abs - return absolute value of an argument
211 * @x: the value. If it is unsigned type, it is converted to signed type first.
212 * char is treated as if it was signed (regardless of whether it really is)
213 * but the macro's return type is preserved as char.
215 * Return: an absolute value of x.
217 #define abs(x) __abs_choose_expr(x, long long, \
218 __abs_choose_expr(x, long, \
219 __abs_choose_expr(x, int, \
220 __abs_choose_expr(x, short, \
221 __abs_choose_expr(x, char, \
222 __builtin_choose_expr( \
223 __builtin_types_compatible_p(typeof(x), char), \
224 (char)({ signed char __x = (x); __x<0?-__x:__x; }), \
225 ((void)0)))))))
227 #define __abs_choose_expr(x, type, other) __builtin_choose_expr( \
228 __builtin_types_compatible_p(typeof(x), signed type) || \
229 __builtin_types_compatible_p(typeof(x), unsigned type), \
230 ({ signed type __x = (x); __x < 0 ? -__x : __x; }), other)
233 * reciprocal_scale - "scale" a value into range [0, ep_ro)
234 * @val: value
235 * @ep_ro: right open interval endpoint
237 * Perform a "reciprocal multiplication" in order to "scale" a value into
238 * range [0, ep_ro), where the upper interval endpoint is right-open.
239 * This is useful, e.g. for accessing a index of an array containing
240 * ep_ro elements, for example. Think of it as sort of modulus, only that
241 * the result isn't that of modulo. ;) Note that if initial input is a
242 * small value, then result will return 0.
244 * Return: a result based on val in interval [0, ep_ro).
246 static inline u32 reciprocal_scale(u32 val, u32 ep_ro)
248 return (u32)(((u64) val * ep_ro) >> 32);
251 #if defined(CONFIG_MMU) && \
252 (defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_DEBUG_ATOMIC_SLEEP))
253 #define might_fault() __might_fault(__FILE__, __LINE__)
254 void __might_fault(const char *file, int line);
255 #else
256 static inline void might_fault(void) { }
257 #endif
259 extern struct atomic_notifier_head panic_notifier_list;
260 extern long (*panic_blink)(int state);
261 __printf(1, 2)
262 void panic(const char *fmt, ...) __noreturn __cold;
263 void nmi_panic(struct pt_regs *regs, const char *msg);
264 extern void oops_enter(void);
265 extern void oops_exit(void);
266 void print_oops_end_marker(void);
267 extern int oops_may_print(void);
268 void do_exit(long error_code) __noreturn;
269 void complete_and_exit(struct completion *, long) __noreturn;
271 /* Internal, do not use. */
272 int __must_check _kstrtoul(const char *s, unsigned int base, unsigned long *res);
273 int __must_check _kstrtol(const char *s, unsigned int base, long *res);
275 int __must_check kstrtoull(const char *s, unsigned int base, unsigned long long *res);
276 int __must_check kstrtoll(const char *s, unsigned int base, long long *res);
279 * kstrtoul - convert a string to an unsigned long
280 * @s: The start of the string. The string must be null-terminated, and may also
281 * include a single newline before its terminating null. The first character
282 * may also be a plus sign, but not a minus sign.
283 * @base: The number base to use. The maximum supported base is 16. If base is
284 * given as 0, then the base of the string is automatically detected with the
285 * conventional semantics - If it begins with 0x the number will be parsed as a
286 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be
287 * parsed as an octal number. Otherwise it will be parsed as a decimal.
288 * @res: Where to write the result of the conversion on success.
290 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
291 * Used as a replacement for the obsolete simple_strtoull. Return code must
292 * be checked.
294 static inline int __must_check kstrtoul(const char *s, unsigned int base, unsigned long *res)
297 * We want to shortcut function call, but
298 * __builtin_types_compatible_p(unsigned long, unsigned long long) = 0.
300 if (sizeof(unsigned long) == sizeof(unsigned long long) &&
301 __alignof__(unsigned long) == __alignof__(unsigned long long))
302 return kstrtoull(s, base, (unsigned long long *)res);
303 else
304 return _kstrtoul(s, base, res);
308 * kstrtol - convert a string to a long
309 * @s: The start of the string. The string must be null-terminated, and may also
310 * include a single newline before its terminating null. The first character
311 * may also be a plus sign or a minus sign.
312 * @base: The number base to use. The maximum supported base is 16. If base is
313 * given as 0, then the base of the string is automatically detected with the
314 * conventional semantics - If it begins with 0x the number will be parsed as a
315 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be
316 * parsed as an octal number. Otherwise it will be parsed as a decimal.
317 * @res: Where to write the result of the conversion on success.
319 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
320 * Used as a replacement for the obsolete simple_strtoull. Return code must
321 * be checked.
323 static inline int __must_check kstrtol(const char *s, unsigned int base, long *res)
326 * We want to shortcut function call, but
327 * __builtin_types_compatible_p(long, long long) = 0.
329 if (sizeof(long) == sizeof(long long) &&
330 __alignof__(long) == __alignof__(long long))
331 return kstrtoll(s, base, (long long *)res);
332 else
333 return _kstrtol(s, base, res);
336 int __must_check kstrtouint(const char *s, unsigned int base, unsigned int *res);
337 int __must_check kstrtoint(const char *s, unsigned int base, int *res);
339 static inline int __must_check kstrtou64(const char *s, unsigned int base, u64 *res)
341 return kstrtoull(s, base, res);
344 static inline int __must_check kstrtos64(const char *s, unsigned int base, s64 *res)
346 return kstrtoll(s, base, res);
349 static inline int __must_check kstrtou32(const char *s, unsigned int base, u32 *res)
351 return kstrtouint(s, base, res);
354 static inline int __must_check kstrtos32(const char *s, unsigned int base, s32 *res)
356 return kstrtoint(s, base, res);
359 int __must_check kstrtou16(const char *s, unsigned int base, u16 *res);
360 int __must_check kstrtos16(const char *s, unsigned int base, s16 *res);
361 int __must_check kstrtou8(const char *s, unsigned int base, u8 *res);
362 int __must_check kstrtos8(const char *s, unsigned int base, s8 *res);
363 int __must_check kstrtobool(const char *s, bool *res);
365 int __must_check kstrtoull_from_user(const char __user *s, size_t count, unsigned int base, unsigned long long *res);
366 int __must_check kstrtoll_from_user(const char __user *s, size_t count, unsigned int base, long long *res);
367 int __must_check kstrtoul_from_user(const char __user *s, size_t count, unsigned int base, unsigned long *res);
368 int __must_check kstrtol_from_user(const char __user *s, size_t count, unsigned int base, long *res);
369 int __must_check kstrtouint_from_user(const char __user *s, size_t count, unsigned int base, unsigned int *res);
370 int __must_check kstrtoint_from_user(const char __user *s, size_t count, unsigned int base, int *res);
371 int __must_check kstrtou16_from_user(const char __user *s, size_t count, unsigned int base, u16 *res);
372 int __must_check kstrtos16_from_user(const char __user *s, size_t count, unsigned int base, s16 *res);
373 int __must_check kstrtou8_from_user(const char __user *s, size_t count, unsigned int base, u8 *res);
374 int __must_check kstrtos8_from_user(const char __user *s, size_t count, unsigned int base, s8 *res);
375 int __must_check kstrtobool_from_user(const char __user *s, size_t count, bool *res);
377 static inline int __must_check kstrtou64_from_user(const char __user *s, size_t count, unsigned int base, u64 *res)
379 return kstrtoull_from_user(s, count, base, res);
382 static inline int __must_check kstrtos64_from_user(const char __user *s, size_t count, unsigned int base, s64 *res)
384 return kstrtoll_from_user(s, count, base, res);
387 static inline int __must_check kstrtou32_from_user(const char __user *s, size_t count, unsigned int base, u32 *res)
389 return kstrtouint_from_user(s, count, base, res);
392 static inline int __must_check kstrtos32_from_user(const char __user *s, size_t count, unsigned int base, s32 *res)
394 return kstrtoint_from_user(s, count, base, res);
397 /* Obsolete, do not use. Use kstrto<foo> instead */
399 extern unsigned long simple_strtoul(const char *,char **,unsigned int);
400 extern long simple_strtol(const char *,char **,unsigned int);
401 extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
402 extern long long simple_strtoll(const char *,char **,unsigned int);
404 extern int num_to_str(char *buf, int size, unsigned long long num);
406 /* lib/printf utilities */
408 extern __printf(2, 3) int sprintf(char *buf, const char * fmt, ...);
409 extern __printf(2, 0) int vsprintf(char *buf, const char *, va_list);
410 extern __printf(3, 4)
411 int snprintf(char *buf, size_t size, const char *fmt, ...);
412 extern __printf(3, 0)
413 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args);
414 extern __printf(3, 4)
415 int scnprintf(char *buf, size_t size, const char *fmt, ...);
416 extern __printf(3, 0)
417 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args);
418 extern __printf(2, 3) __malloc
419 char *kasprintf(gfp_t gfp, const char *fmt, ...);
420 extern __printf(2, 0) __malloc
421 char *kvasprintf(gfp_t gfp, const char *fmt, va_list args);
422 extern __printf(2, 0)
423 const char *kvasprintf_const(gfp_t gfp, const char *fmt, va_list args);
425 extern __scanf(2, 3)
426 int sscanf(const char *, const char *, ...);
427 extern __scanf(2, 0)
428 int vsscanf(const char *, const char *, va_list);
430 extern int get_option(char **str, int *pint);
431 extern char *get_options(const char *str, int nints, int *ints);
432 extern unsigned long long memparse(const char *ptr, char **retptr);
433 extern bool parse_option_str(const char *str, const char *option);
435 extern int core_kernel_text(unsigned long addr);
436 extern int core_kernel_data(unsigned long addr);
437 extern int __kernel_text_address(unsigned long addr);
438 extern int kernel_text_address(unsigned long addr);
439 extern int func_ptr_is_kernel_text(void *ptr);
441 unsigned long int_sqrt(unsigned long);
443 extern void bust_spinlocks(int yes);
444 extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */
445 extern int panic_timeout;
446 extern int panic_on_oops;
447 extern int panic_on_unrecovered_nmi;
448 extern int panic_on_io_nmi;
449 extern int panic_on_warn;
450 extern int sysctl_panic_on_rcu_stall;
451 extern int sysctl_panic_on_stackoverflow;
453 extern bool crash_kexec_post_notifiers;
456 * panic_cpu is used for synchronizing panic() and crash_kexec() execution. It
457 * holds a CPU number which is executing panic() currently. A value of
458 * PANIC_CPU_INVALID means no CPU has entered panic() or crash_kexec().
460 extern atomic_t panic_cpu;
461 #define PANIC_CPU_INVALID -1
464 * Only to be used by arch init code. If the user over-wrote the default
465 * CONFIG_PANIC_TIMEOUT, honor it.
467 static inline void set_arch_panic_timeout(int timeout, int arch_default_timeout)
469 if (panic_timeout == arch_default_timeout)
470 panic_timeout = timeout;
472 extern const char *print_tainted(void);
473 enum lockdep_ok {
474 LOCKDEP_STILL_OK,
475 LOCKDEP_NOW_UNRELIABLE
477 extern void add_taint(unsigned flag, enum lockdep_ok);
478 extern int test_taint(unsigned flag);
479 extern unsigned long get_taint(void);
480 extern int root_mountflags;
482 extern bool early_boot_irqs_disabled;
484 /* Values used for system_state */
485 extern enum system_states {
486 SYSTEM_BOOTING,
487 SYSTEM_RUNNING,
488 SYSTEM_HALT,
489 SYSTEM_POWER_OFF,
490 SYSTEM_RESTART,
491 } system_state;
493 #define TAINT_PROPRIETARY_MODULE 0
494 #define TAINT_FORCED_MODULE 1
495 #define TAINT_CPU_OUT_OF_SPEC 2
496 #define TAINT_FORCED_RMMOD 3
497 #define TAINT_MACHINE_CHECK 4
498 #define TAINT_BAD_PAGE 5
499 #define TAINT_USER 6
500 #define TAINT_DIE 7
501 #define TAINT_OVERRIDDEN_ACPI_TABLE 8
502 #define TAINT_WARN 9
503 #define TAINT_CRAP 10
504 #define TAINT_FIRMWARE_WORKAROUND 11
505 #define TAINT_OOT_MODULE 12
506 #define TAINT_UNSIGNED_MODULE 13
507 #define TAINT_SOFTLOCKUP 14
508 #define TAINT_LIVEPATCH 15
510 extern const char hex_asc[];
511 #define hex_asc_lo(x) hex_asc[((x) & 0x0f)]
512 #define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4]
514 static inline char *hex_byte_pack(char *buf, u8 byte)
516 *buf++ = hex_asc_hi(byte);
517 *buf++ = hex_asc_lo(byte);
518 return buf;
521 extern const char hex_asc_upper[];
522 #define hex_asc_upper_lo(x) hex_asc_upper[((x) & 0x0f)]
523 #define hex_asc_upper_hi(x) hex_asc_upper[((x) & 0xf0) >> 4]
525 static inline char *hex_byte_pack_upper(char *buf, u8 byte)
527 *buf++ = hex_asc_upper_hi(byte);
528 *buf++ = hex_asc_upper_lo(byte);
529 return buf;
532 extern int hex_to_bin(char ch);
533 extern int __must_check hex2bin(u8 *dst, const char *src, size_t count);
534 extern char *bin2hex(char *dst, const void *src, size_t count);
536 bool mac_pton(const char *s, u8 *mac);
539 * General tracing related utility functions - trace_printk(),
540 * tracing_on/tracing_off and tracing_start()/tracing_stop
542 * Use tracing_on/tracing_off when you want to quickly turn on or off
543 * tracing. It simply enables or disables the recording of the trace events.
544 * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on
545 * file, which gives a means for the kernel and userspace to interact.
546 * Place a tracing_off() in the kernel where you want tracing to end.
547 * From user space, examine the trace, and then echo 1 > tracing_on
548 * to continue tracing.
550 * tracing_stop/tracing_start has slightly more overhead. It is used
551 * by things like suspend to ram where disabling the recording of the
552 * trace is not enough, but tracing must actually stop because things
553 * like calling smp_processor_id() may crash the system.
555 * Most likely, you want to use tracing_on/tracing_off.
558 enum ftrace_dump_mode {
559 DUMP_NONE,
560 DUMP_ALL,
561 DUMP_ORIG,
564 #ifdef CONFIG_TRACING
565 void tracing_on(void);
566 void tracing_off(void);
567 int tracing_is_on(void);
568 void tracing_snapshot(void);
569 void tracing_snapshot_alloc(void);
571 extern void tracing_start(void);
572 extern void tracing_stop(void);
574 static inline __printf(1, 2)
575 void ____trace_printk_check_format(const char *fmt, ...)
578 #define __trace_printk_check_format(fmt, args...) \
579 do { \
580 if (0) \
581 ____trace_printk_check_format(fmt, ##args); \
582 } while (0)
585 * trace_printk - printf formatting in the ftrace buffer
586 * @fmt: the printf format for printing
588 * Note: __trace_printk is an internal function for trace_printk and
589 * the @ip is passed in via the trace_printk macro.
591 * This function allows a kernel developer to debug fast path sections
592 * that printk is not appropriate for. By scattering in various
593 * printk like tracing in the code, a developer can quickly see
594 * where problems are occurring.
596 * This is intended as a debugging tool for the developer only.
597 * Please refrain from leaving trace_printks scattered around in
598 * your code. (Extra memory is used for special buffers that are
599 * allocated when trace_printk() is used)
601 * A little optization trick is done here. If there's only one
602 * argument, there's no need to scan the string for printf formats.
603 * The trace_puts() will suffice. But how can we take advantage of
604 * using trace_puts() when trace_printk() has only one argument?
605 * By stringifying the args and checking the size we can tell
606 * whether or not there are args. __stringify((__VA_ARGS__)) will
607 * turn into "()\0" with a size of 3 when there are no args, anything
608 * else will be bigger. All we need to do is define a string to this,
609 * and then take its size and compare to 3. If it's bigger, use
610 * do_trace_printk() otherwise, optimize it to trace_puts(). Then just
611 * let gcc optimize the rest.
614 #define trace_printk(fmt, ...) \
615 do { \
616 char _______STR[] = __stringify((__VA_ARGS__)); \
617 if (sizeof(_______STR) > 3) \
618 do_trace_printk(fmt, ##__VA_ARGS__); \
619 else \
620 trace_puts(fmt); \
621 } while (0)
623 #define do_trace_printk(fmt, args...) \
624 do { \
625 static const char *trace_printk_fmt __used \
626 __attribute__((section("__trace_printk_fmt"))) = \
627 __builtin_constant_p(fmt) ? fmt : NULL; \
629 __trace_printk_check_format(fmt, ##args); \
631 if (__builtin_constant_p(fmt)) \
632 __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \
633 else \
634 __trace_printk(_THIS_IP_, fmt, ##args); \
635 } while (0)
637 extern __printf(2, 3)
638 int __trace_bprintk(unsigned long ip, const char *fmt, ...);
640 extern __printf(2, 3)
641 int __trace_printk(unsigned long ip, const char *fmt, ...);
644 * trace_puts - write a string into the ftrace buffer
645 * @str: the string to record
647 * Note: __trace_bputs is an internal function for trace_puts and
648 * the @ip is passed in via the trace_puts macro.
650 * This is similar to trace_printk() but is made for those really fast
651 * paths that a developer wants the least amount of "Heisenbug" affects,
652 * where the processing of the print format is still too much.
654 * This function allows a kernel developer to debug fast path sections
655 * that printk is not appropriate for. By scattering in various
656 * printk like tracing in the code, a developer can quickly see
657 * where problems are occurring.
659 * This is intended as a debugging tool for the developer only.
660 * Please refrain from leaving trace_puts scattered around in
661 * your code. (Extra memory is used for special buffers that are
662 * allocated when trace_puts() is used)
664 * Returns: 0 if nothing was written, positive # if string was.
665 * (1 when __trace_bputs is used, strlen(str) when __trace_puts is used)
668 #define trace_puts(str) ({ \
669 static const char *trace_printk_fmt __used \
670 __attribute__((section("__trace_printk_fmt"))) = \
671 __builtin_constant_p(str) ? str : NULL; \
673 if (__builtin_constant_p(str)) \
674 __trace_bputs(_THIS_IP_, trace_printk_fmt); \
675 else \
676 __trace_puts(_THIS_IP_, str, strlen(str)); \
678 extern int __trace_bputs(unsigned long ip, const char *str);
679 extern int __trace_puts(unsigned long ip, const char *str, int size);
681 extern void trace_dump_stack(int skip);
684 * The double __builtin_constant_p is because gcc will give us an error
685 * if we try to allocate the static variable to fmt if it is not a
686 * constant. Even with the outer if statement.
688 #define ftrace_vprintk(fmt, vargs) \
689 do { \
690 if (__builtin_constant_p(fmt)) { \
691 static const char *trace_printk_fmt __used \
692 __attribute__((section("__trace_printk_fmt"))) = \
693 __builtin_constant_p(fmt) ? fmt : NULL; \
695 __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \
696 } else \
697 __ftrace_vprintk(_THIS_IP_, fmt, vargs); \
698 } while (0)
700 extern __printf(2, 0) int
701 __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap);
703 extern __printf(2, 0) int
704 __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap);
706 extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode);
707 #else
708 static inline void tracing_start(void) { }
709 static inline void tracing_stop(void) { }
710 static inline void trace_dump_stack(int skip) { }
712 static inline void tracing_on(void) { }
713 static inline void tracing_off(void) { }
714 static inline int tracing_is_on(void) { return 0; }
715 static inline void tracing_snapshot(void) { }
716 static inline void tracing_snapshot_alloc(void) { }
718 static inline __printf(1, 2)
719 int trace_printk(const char *fmt, ...)
721 return 0;
723 static __printf(1, 0) inline int
724 ftrace_vprintk(const char *fmt, va_list ap)
726 return 0;
728 static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { }
729 #endif /* CONFIG_TRACING */
732 * min()/max()/clamp() macros that also do
733 * strict type-checking.. See the
734 * "unnecessary" pointer comparison.
736 #define __min(t1, t2, min1, min2, x, y) ({ \
737 t1 min1 = (x); \
738 t2 min2 = (y); \
739 (void) (&min1 == &min2); \
740 min1 < min2 ? min1 : min2; })
741 #define min(x, y) \
742 __min(typeof(x), typeof(y), \
743 __UNIQUE_ID(min1_), __UNIQUE_ID(min2_), \
744 x, y)
746 #define __max(t1, t2, max1, max2, x, y) ({ \
747 t1 max1 = (x); \
748 t2 max2 = (y); \
749 (void) (&max1 == &max2); \
750 max1 > max2 ? max1 : max2; })
751 #define max(x, y) \
752 __max(typeof(x), typeof(y), \
753 __UNIQUE_ID(max1_), __UNIQUE_ID(max2_), \
754 x, y)
756 #define min3(x, y, z) min((typeof(x))min(x, y), z)
757 #define max3(x, y, z) max((typeof(x))max(x, y), z)
760 * min_not_zero - return the minimum that is _not_ zero, unless both are zero
761 * @x: value1
762 * @y: value2
764 #define min_not_zero(x, y) ({ \
765 typeof(x) __x = (x); \
766 typeof(y) __y = (y); \
767 __x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); })
770 * clamp - return a value clamped to a given range with strict typechecking
771 * @val: current value
772 * @lo: lowest allowable value
773 * @hi: highest allowable value
775 * This macro does strict typechecking of lo/hi to make sure they are of the
776 * same type as val. See the unnecessary pointer comparisons.
778 #define clamp(val, lo, hi) min((typeof(val))max(val, lo), hi)
781 * ..and if you can't take the strict
782 * types, you can specify one yourself.
784 * Or not use min/max/clamp at all, of course.
786 #define min_t(type, x, y) \
787 __min(type, type, \
788 __UNIQUE_ID(min1_), __UNIQUE_ID(min2_), \
789 x, y)
791 #define max_t(type, x, y) \
792 __max(type, type, \
793 __UNIQUE_ID(min1_), __UNIQUE_ID(min2_), \
794 x, y)
797 * clamp_t - return a value clamped to a given range using a given type
798 * @type: the type of variable to use
799 * @val: current value
800 * @lo: minimum allowable value
801 * @hi: maximum allowable value
803 * This macro does no typechecking and uses temporary variables of type
804 * 'type' to make all the comparisons.
806 #define clamp_t(type, val, lo, hi) min_t(type, max_t(type, val, lo), hi)
809 * clamp_val - return a value clamped to a given range using val's type
810 * @val: current value
811 * @lo: minimum allowable value
812 * @hi: maximum allowable value
814 * This macro does no typechecking and uses temporary variables of whatever
815 * type the input argument 'val' is. This is useful when val is an unsigned
816 * type and min and max are literals that will otherwise be assigned a signed
817 * integer type.
819 #define clamp_val(val, lo, hi) clamp_t(typeof(val), val, lo, hi)
823 * swap - swap value of @a and @b
825 #define swap(a, b) \
826 do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0)
829 * container_of - cast a member of a structure out to the containing structure
830 * @ptr: the pointer to the member.
831 * @type: the type of the container struct this is embedded in.
832 * @member: the name of the member within the struct.
835 #define container_of(ptr, type, member) ({ \
836 const typeof( ((type *)0)->member ) *__mptr = (ptr); \
837 (type *)( (char *)__mptr - offsetof(type,member) );})
839 /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
840 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
841 # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD
842 #endif
844 /* Permissions on a sysfs file: you didn't miss the 0 prefix did you? */
845 #define VERIFY_OCTAL_PERMISSIONS(perms) \
846 (BUILD_BUG_ON_ZERO((perms) < 0) + \
847 BUILD_BUG_ON_ZERO((perms) > 0777) + \
848 /* USER_READABLE >= GROUP_READABLE >= OTHER_READABLE */ \
849 BUILD_BUG_ON_ZERO((((perms) >> 6) & 4) < (((perms) >> 3) & 4)) + \
850 BUILD_BUG_ON_ZERO((((perms) >> 3) & 4) < ((perms) & 4)) + \
851 /* USER_WRITABLE >= GROUP_WRITABLE */ \
852 BUILD_BUG_ON_ZERO((((perms) >> 6) & 2) < (((perms) >> 3) & 2)) + \
853 /* OTHER_WRITABLE? Generally considered a bad idea. */ \
854 BUILD_BUG_ON_ZERO((perms) & 2) + \
855 (perms))
856 #endif