thermal: exynos: Add TMU support for Exynos7 SoC
[linux-2.6/btrfs-unstable.git] / include / linux / kernel.h
blob5449d2f4a1efa51203ecd27237ddf9899af2d59a
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 <linux/dynamic_debug.h>
15 #include <asm/byteorder.h>
16 #include <uapi/linux/kernel.h>
18 #define USHRT_MAX ((u16)(~0U))
19 #define SHRT_MAX ((s16)(USHRT_MAX>>1))
20 #define SHRT_MIN ((s16)(-SHRT_MAX - 1))
21 #define INT_MAX ((int)(~0U>>1))
22 #define INT_MIN (-INT_MAX - 1)
23 #define UINT_MAX (~0U)
24 #define LONG_MAX ((long)(~0UL>>1))
25 #define LONG_MIN (-LONG_MAX - 1)
26 #define ULONG_MAX (~0UL)
27 #define LLONG_MAX ((long long)(~0ULL>>1))
28 #define LLONG_MIN (-LLONG_MAX - 1)
29 #define ULLONG_MAX (~0ULL)
30 #define SIZE_MAX (~(size_t)0)
32 #define U8_MAX ((u8)~0U)
33 #define S8_MAX ((s8)(U8_MAX>>1))
34 #define S8_MIN ((s8)(-S8_MAX - 1))
35 #define U16_MAX ((u16)~0U)
36 #define S16_MAX ((s16)(U16_MAX>>1))
37 #define S16_MIN ((s16)(-S16_MAX - 1))
38 #define U32_MAX ((u32)~0U)
39 #define S32_MAX ((s32)(U32_MAX>>1))
40 #define S32_MIN ((s32)(-S32_MAX - 1))
41 #define U64_MAX ((u64)~0ULL)
42 #define S64_MAX ((s64)(U64_MAX>>1))
43 #define S64_MIN ((s64)(-S64_MAX - 1))
45 #define STACK_MAGIC 0xdeadbeef
47 #define REPEAT_BYTE(x) ((~0ul / 0xff) * (x))
49 #define ALIGN(x, a) __ALIGN_KERNEL((x), (a))
50 #define __ALIGN_MASK(x, mask) __ALIGN_KERNEL_MASK((x), (mask))
51 #define PTR_ALIGN(p, a) ((typeof(p))ALIGN((unsigned long)(p), (a)))
52 #define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0)
54 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
57 * This looks more complex than it should be. But we need to
58 * get the type for the ~ right in round_down (it needs to be
59 * as wide as the result!), and we want to evaluate the macro
60 * arguments just once each.
62 #define __round_mask(x, y) ((__typeof__(x))((y)-1))
63 #define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1)
64 #define round_down(x, y) ((x) & ~__round_mask(x, y))
66 #define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))
67 #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
68 #define DIV_ROUND_UP_ULL(ll,d) \
69 ({ unsigned long long _tmp = (ll)+(d)-1; do_div(_tmp, d); _tmp; })
71 #if BITS_PER_LONG == 32
72 # define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP_ULL(ll, d)
73 #else
74 # define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP(ll,d)
75 #endif
77 /* The `const' in roundup() prevents gcc-3.3 from calling __divdi3 */
78 #define roundup(x, y) ( \
79 { \
80 const typeof(y) __y = y; \
81 (((x) + (__y - 1)) / __y) * __y; \
82 } \
84 #define rounddown(x, y) ( \
85 { \
86 typeof(x) __x = (x); \
87 __x - (__x % (y)); \
88 } \
92 * Divide positive or negative dividend by positive divisor and round
93 * to closest integer. Result is undefined for negative divisors and
94 * for negative dividends if the divisor variable type is unsigned.
96 #define DIV_ROUND_CLOSEST(x, divisor)( \
97 { \
98 typeof(x) __x = x; \
99 typeof(divisor) __d = divisor; \
100 (((typeof(x))-1) > 0 || \
101 ((typeof(divisor))-1) > 0 || (__x) > 0) ? \
102 (((__x) + ((__d) / 2)) / (__d)) : \
103 (((__x) - ((__d) / 2)) / (__d)); \
108 * Multiplies an integer by a fraction, while avoiding unnecessary
109 * overflow or loss of precision.
111 #define mult_frac(x, numer, denom)( \
113 typeof(x) quot = (x) / (denom); \
114 typeof(x) rem = (x) % (denom); \
115 (quot * (numer)) + ((rem * (numer)) / (denom)); \
120 #define _RET_IP_ (unsigned long)__builtin_return_address(0)
121 #define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; })
123 #ifdef CONFIG_LBDAF
124 # include <asm/div64.h>
125 # define sector_div(a, b) do_div(a, b)
126 #else
127 # define sector_div(n, b)( \
129 int _res; \
130 _res = (n) % (b); \
131 (n) /= (b); \
132 _res; \
135 #endif
138 * upper_32_bits - return bits 32-63 of a number
139 * @n: the number we're accessing
141 * A basic shift-right of a 64- or 32-bit quantity. Use this to suppress
142 * the "right shift count >= width of type" warning when that quantity is
143 * 32-bits.
145 #define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))
148 * lower_32_bits - return bits 0-31 of a number
149 * @n: the number we're accessing
151 #define lower_32_bits(n) ((u32)(n))
153 struct completion;
154 struct pt_regs;
155 struct user;
157 #ifdef CONFIG_PREEMPT_VOLUNTARY
158 extern int _cond_resched(void);
159 # define might_resched() _cond_resched()
160 #else
161 # define might_resched() do { } while (0)
162 #endif
164 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
165 void ___might_sleep(const char *file, int line, int preempt_offset);
166 void __might_sleep(const char *file, int line, int preempt_offset);
168 * might_sleep - annotation for functions that can sleep
170 * this macro will print a stack trace if it is executed in an atomic
171 * context (spinlock, irq-handler, ...).
173 * This is a useful debugging help to be able to catch problems early and not
174 * be bitten later when the calling function happens to sleep when it is not
175 * supposed to.
177 # define might_sleep() \
178 do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
179 # define sched_annotate_sleep() __set_current_state(TASK_RUNNING)
180 #else
181 static inline void ___might_sleep(const char *file, int line,
182 int preempt_offset) { }
183 static inline void __might_sleep(const char *file, int line,
184 int preempt_offset) { }
185 # define might_sleep() do { might_resched(); } while (0)
186 # define sched_annotate_sleep() do { } while (0)
187 #endif
189 #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
192 * abs() handles unsigned and signed longs, ints, shorts and chars. For all
193 * input types abs() returns a signed long.
194 * abs() should not be used for 64-bit types (s64, u64, long long) - use abs64()
195 * for those.
197 #define abs(x) ({ \
198 long ret; \
199 if (sizeof(x) == sizeof(long)) { \
200 long __x = (x); \
201 ret = (__x < 0) ? -__x : __x; \
202 } else { \
203 int __x = (x); \
204 ret = (__x < 0) ? -__x : __x; \
206 ret; \
209 #define abs64(x) ({ \
210 s64 __x = (x); \
211 (__x < 0) ? -__x : __x; \
215 * reciprocal_scale - "scale" a value into range [0, ep_ro)
216 * @val: value
217 * @ep_ro: right open interval endpoint
219 * Perform a "reciprocal multiplication" in order to "scale" a value into
220 * range [0, ep_ro), where the upper interval endpoint is right-open.
221 * This is useful, e.g. for accessing a index of an array containing
222 * ep_ro elements, for example. Think of it as sort of modulus, only that
223 * the result isn't that of modulo. ;) Note that if initial input is a
224 * small value, then result will return 0.
226 * Return: a result based on val in interval [0, ep_ro).
228 static inline u32 reciprocal_scale(u32 val, u32 ep_ro)
230 return (u32)(((u64) val * ep_ro) >> 32);
233 #if defined(CONFIG_MMU) && \
234 (defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_DEBUG_ATOMIC_SLEEP))
235 void might_fault(void);
236 #else
237 static inline void might_fault(void) { }
238 #endif
240 extern struct atomic_notifier_head panic_notifier_list;
241 extern long (*panic_blink)(int state);
242 __printf(1, 2)
243 void panic(const char *fmt, ...)
244 __noreturn __cold;
245 extern void oops_enter(void);
246 extern void oops_exit(void);
247 void print_oops_end_marker(void);
248 extern int oops_may_print(void);
249 void do_exit(long error_code)
250 __noreturn;
251 void complete_and_exit(struct completion *, long)
252 __noreturn;
254 /* Internal, do not use. */
255 int __must_check _kstrtoul(const char *s, unsigned int base, unsigned long *res);
256 int __must_check _kstrtol(const char *s, unsigned int base, long *res);
258 int __must_check kstrtoull(const char *s, unsigned int base, unsigned long long *res);
259 int __must_check kstrtoll(const char *s, unsigned int base, long long *res);
262 * kstrtoul - convert a string to an unsigned long
263 * @s: The start of the string. The string must be null-terminated, and may also
264 * include a single newline before its terminating null. The first character
265 * may also be a plus sign, but not a minus sign.
266 * @base: The number base to use. The maximum supported base is 16. If base is
267 * given as 0, then the base of the string is automatically detected with the
268 * conventional semantics - If it begins with 0x the number will be parsed as a
269 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be
270 * parsed as an octal number. Otherwise it will be parsed as a decimal.
271 * @res: Where to write the result of the conversion on success.
273 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
274 * Used as a replacement for the obsolete simple_strtoull. Return code must
275 * be checked.
277 static inline int __must_check kstrtoul(const char *s, unsigned int base, unsigned long *res)
280 * We want to shortcut function call, but
281 * __builtin_types_compatible_p(unsigned long, unsigned long long) = 0.
283 if (sizeof(unsigned long) == sizeof(unsigned long long) &&
284 __alignof__(unsigned long) == __alignof__(unsigned long long))
285 return kstrtoull(s, base, (unsigned long long *)res);
286 else
287 return _kstrtoul(s, base, res);
291 * kstrtol - convert a string to a long
292 * @s: The start of the string. The string must be null-terminated, and may also
293 * include a single newline before its terminating null. The first character
294 * may also be a plus sign or a minus sign.
295 * @base: The number base to use. The maximum supported base is 16. If base is
296 * given as 0, then the base of the string is automatically detected with the
297 * conventional semantics - If it begins with 0x the number will be parsed as a
298 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be
299 * parsed as an octal number. Otherwise it will be parsed as a decimal.
300 * @res: Where to write the result of the conversion on success.
302 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
303 * Used as a replacement for the obsolete simple_strtoull. Return code must
304 * be checked.
306 static inline int __must_check kstrtol(const char *s, unsigned int base, long *res)
309 * We want to shortcut function call, but
310 * __builtin_types_compatible_p(long, long long) = 0.
312 if (sizeof(long) == sizeof(long long) &&
313 __alignof__(long) == __alignof__(long long))
314 return kstrtoll(s, base, (long long *)res);
315 else
316 return _kstrtol(s, base, res);
319 int __must_check kstrtouint(const char *s, unsigned int base, unsigned int *res);
320 int __must_check kstrtoint(const char *s, unsigned int base, int *res);
322 static inline int __must_check kstrtou64(const char *s, unsigned int base, u64 *res)
324 return kstrtoull(s, base, res);
327 static inline int __must_check kstrtos64(const char *s, unsigned int base, s64 *res)
329 return kstrtoll(s, base, res);
332 static inline int __must_check kstrtou32(const char *s, unsigned int base, u32 *res)
334 return kstrtouint(s, base, res);
337 static inline int __must_check kstrtos32(const char *s, unsigned int base, s32 *res)
339 return kstrtoint(s, base, res);
342 int __must_check kstrtou16(const char *s, unsigned int base, u16 *res);
343 int __must_check kstrtos16(const char *s, unsigned int base, s16 *res);
344 int __must_check kstrtou8(const char *s, unsigned int base, u8 *res);
345 int __must_check kstrtos8(const char *s, unsigned int base, s8 *res);
347 int __must_check kstrtoull_from_user(const char __user *s, size_t count, unsigned int base, unsigned long long *res);
348 int __must_check kstrtoll_from_user(const char __user *s, size_t count, unsigned int base, long long *res);
349 int __must_check kstrtoul_from_user(const char __user *s, size_t count, unsigned int base, unsigned long *res);
350 int __must_check kstrtol_from_user(const char __user *s, size_t count, unsigned int base, long *res);
351 int __must_check kstrtouint_from_user(const char __user *s, size_t count, unsigned int base, unsigned int *res);
352 int __must_check kstrtoint_from_user(const char __user *s, size_t count, unsigned int base, int *res);
353 int __must_check kstrtou16_from_user(const char __user *s, size_t count, unsigned int base, u16 *res);
354 int __must_check kstrtos16_from_user(const char __user *s, size_t count, unsigned int base, s16 *res);
355 int __must_check kstrtou8_from_user(const char __user *s, size_t count, unsigned int base, u8 *res);
356 int __must_check kstrtos8_from_user(const char __user *s, size_t count, unsigned int base, s8 *res);
358 static inline int __must_check kstrtou64_from_user(const char __user *s, size_t count, unsigned int base, u64 *res)
360 return kstrtoull_from_user(s, count, base, res);
363 static inline int __must_check kstrtos64_from_user(const char __user *s, size_t count, unsigned int base, s64 *res)
365 return kstrtoll_from_user(s, count, base, res);
368 static inline int __must_check kstrtou32_from_user(const char __user *s, size_t count, unsigned int base, u32 *res)
370 return kstrtouint_from_user(s, count, base, res);
373 static inline int __must_check kstrtos32_from_user(const char __user *s, size_t count, unsigned int base, s32 *res)
375 return kstrtoint_from_user(s, count, base, res);
378 /* Obsolete, do not use. Use kstrto<foo> instead */
380 extern unsigned long simple_strtoul(const char *,char **,unsigned int);
381 extern long simple_strtol(const char *,char **,unsigned int);
382 extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
383 extern long long simple_strtoll(const char *,char **,unsigned int);
385 extern int num_to_str(char *buf, int size, unsigned long long num);
387 /* lib/printf utilities */
389 extern __printf(2, 3) int sprintf(char *buf, const char * fmt, ...);
390 extern __printf(2, 0) int vsprintf(char *buf, const char *, va_list);
391 extern __printf(3, 4)
392 int snprintf(char *buf, size_t size, const char *fmt, ...);
393 extern __printf(3, 0)
394 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args);
395 extern __printf(3, 4)
396 int scnprintf(char *buf, size_t size, const char *fmt, ...);
397 extern __printf(3, 0)
398 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args);
399 extern __printf(2, 3)
400 char *kasprintf(gfp_t gfp, const char *fmt, ...);
401 extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args);
403 extern __scanf(2, 3)
404 int sscanf(const char *, const char *, ...);
405 extern __scanf(2, 0)
406 int vsscanf(const char *, const char *, va_list);
408 extern int get_option(char **str, int *pint);
409 extern char *get_options(const char *str, int nints, int *ints);
410 extern unsigned long long memparse(const char *ptr, char **retptr);
411 extern bool parse_option_str(const char *str, const char *option);
413 extern int core_kernel_text(unsigned long addr);
414 extern int core_kernel_data(unsigned long addr);
415 extern int __kernel_text_address(unsigned long addr);
416 extern int kernel_text_address(unsigned long addr);
417 extern int func_ptr_is_kernel_text(void *ptr);
419 unsigned long int_sqrt(unsigned long);
421 extern void bust_spinlocks(int yes);
422 extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */
423 extern int panic_timeout;
424 extern int panic_on_oops;
425 extern int panic_on_unrecovered_nmi;
426 extern int panic_on_io_nmi;
427 extern int panic_on_warn;
428 extern int sysctl_panic_on_stackoverflow;
430 * Only to be used by arch init code. If the user over-wrote the default
431 * CONFIG_PANIC_TIMEOUT, honor it.
433 static inline void set_arch_panic_timeout(int timeout, int arch_default_timeout)
435 if (panic_timeout == arch_default_timeout)
436 panic_timeout = timeout;
438 extern const char *print_tainted(void);
439 enum lockdep_ok {
440 LOCKDEP_STILL_OK,
441 LOCKDEP_NOW_UNRELIABLE
443 extern void add_taint(unsigned flag, enum lockdep_ok);
444 extern int test_taint(unsigned flag);
445 extern unsigned long get_taint(void);
446 extern int root_mountflags;
448 extern bool early_boot_irqs_disabled;
450 /* Values used for system_state */
451 extern enum system_states {
452 SYSTEM_BOOTING,
453 SYSTEM_RUNNING,
454 SYSTEM_HALT,
455 SYSTEM_POWER_OFF,
456 SYSTEM_RESTART,
457 } system_state;
459 #define TAINT_PROPRIETARY_MODULE 0
460 #define TAINT_FORCED_MODULE 1
461 #define TAINT_CPU_OUT_OF_SPEC 2
462 #define TAINT_FORCED_RMMOD 3
463 #define TAINT_MACHINE_CHECK 4
464 #define TAINT_BAD_PAGE 5
465 #define TAINT_USER 6
466 #define TAINT_DIE 7
467 #define TAINT_OVERRIDDEN_ACPI_TABLE 8
468 #define TAINT_WARN 9
469 #define TAINT_CRAP 10
470 #define TAINT_FIRMWARE_WORKAROUND 11
471 #define TAINT_OOT_MODULE 12
472 #define TAINT_UNSIGNED_MODULE 13
473 #define TAINT_SOFTLOCKUP 14
475 extern const char hex_asc[];
476 #define hex_asc_lo(x) hex_asc[((x) & 0x0f)]
477 #define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4]
479 static inline char *hex_byte_pack(char *buf, u8 byte)
481 *buf++ = hex_asc_hi(byte);
482 *buf++ = hex_asc_lo(byte);
483 return buf;
486 extern const char hex_asc_upper[];
487 #define hex_asc_upper_lo(x) hex_asc_upper[((x) & 0x0f)]
488 #define hex_asc_upper_hi(x) hex_asc_upper[((x) & 0xf0) >> 4]
490 static inline char *hex_byte_pack_upper(char *buf, u8 byte)
492 *buf++ = hex_asc_upper_hi(byte);
493 *buf++ = hex_asc_upper_lo(byte);
494 return buf;
497 extern int hex_to_bin(char ch);
498 extern int __must_check hex2bin(u8 *dst, const char *src, size_t count);
499 extern char *bin2hex(char *dst, const void *src, size_t count);
501 bool mac_pton(const char *s, u8 *mac);
504 * General tracing related utility functions - trace_printk(),
505 * tracing_on/tracing_off and tracing_start()/tracing_stop
507 * Use tracing_on/tracing_off when you want to quickly turn on or off
508 * tracing. It simply enables or disables the recording of the trace events.
509 * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on
510 * file, which gives a means for the kernel and userspace to interact.
511 * Place a tracing_off() in the kernel where you want tracing to end.
512 * From user space, examine the trace, and then echo 1 > tracing_on
513 * to continue tracing.
515 * tracing_stop/tracing_start has slightly more overhead. It is used
516 * by things like suspend to ram where disabling the recording of the
517 * trace is not enough, but tracing must actually stop because things
518 * like calling smp_processor_id() may crash the system.
520 * Most likely, you want to use tracing_on/tracing_off.
522 #ifdef CONFIG_RING_BUFFER
523 /* trace_off_permanent stops recording with no way to bring it back */
524 void tracing_off_permanent(void);
525 #else
526 static inline void tracing_off_permanent(void) { }
527 #endif
529 enum ftrace_dump_mode {
530 DUMP_NONE,
531 DUMP_ALL,
532 DUMP_ORIG,
535 #ifdef CONFIG_TRACING
536 void tracing_on(void);
537 void tracing_off(void);
538 int tracing_is_on(void);
539 void tracing_snapshot(void);
540 void tracing_snapshot_alloc(void);
542 extern void tracing_start(void);
543 extern void tracing_stop(void);
545 static inline __printf(1, 2)
546 void ____trace_printk_check_format(const char *fmt, ...)
549 #define __trace_printk_check_format(fmt, args...) \
550 do { \
551 if (0) \
552 ____trace_printk_check_format(fmt, ##args); \
553 } while (0)
556 * trace_printk - printf formatting in the ftrace buffer
557 * @fmt: the printf format for printing
559 * Note: __trace_printk is an internal function for trace_printk and
560 * the @ip is passed in via the trace_printk macro.
562 * This function allows a kernel developer to debug fast path sections
563 * that printk is not appropriate for. By scattering in various
564 * printk like tracing in the code, a developer can quickly see
565 * where problems are occurring.
567 * This is intended as a debugging tool for the developer only.
568 * Please refrain from leaving trace_printks scattered around in
569 * your code. (Extra memory is used for special buffers that are
570 * allocated when trace_printk() is used)
572 * A little optization trick is done here. If there's only one
573 * argument, there's no need to scan the string for printf formats.
574 * The trace_puts() will suffice. But how can we take advantage of
575 * using trace_puts() when trace_printk() has only one argument?
576 * By stringifying the args and checking the size we can tell
577 * whether or not there are args. __stringify((__VA_ARGS__)) will
578 * turn into "()\0" with a size of 3 when there are no args, anything
579 * else will be bigger. All we need to do is define a string to this,
580 * and then take its size and compare to 3. If it's bigger, use
581 * do_trace_printk() otherwise, optimize it to trace_puts(). Then just
582 * let gcc optimize the rest.
585 #define trace_printk(fmt, ...) \
586 do { \
587 char _______STR[] = __stringify((__VA_ARGS__)); \
588 if (sizeof(_______STR) > 3) \
589 do_trace_printk(fmt, ##__VA_ARGS__); \
590 else \
591 trace_puts(fmt); \
592 } while (0)
594 #define do_trace_printk(fmt, args...) \
595 do { \
596 static const char *trace_printk_fmt \
597 __attribute__((section("__trace_printk_fmt"))) = \
598 __builtin_constant_p(fmt) ? fmt : NULL; \
600 __trace_printk_check_format(fmt, ##args); \
602 if (__builtin_constant_p(fmt)) \
603 __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \
604 else \
605 __trace_printk(_THIS_IP_, fmt, ##args); \
606 } while (0)
608 extern __printf(2, 3)
609 int __trace_bprintk(unsigned long ip, const char *fmt, ...);
611 extern __printf(2, 3)
612 int __trace_printk(unsigned long ip, const char *fmt, ...);
615 * trace_puts - write a string into the ftrace buffer
616 * @str: the string to record
618 * Note: __trace_bputs is an internal function for trace_puts and
619 * the @ip is passed in via the trace_puts macro.
621 * This is similar to trace_printk() but is made for those really fast
622 * paths that a developer wants the least amount of "Heisenbug" affects,
623 * where the processing of the print format is still too much.
625 * This function allows a kernel developer to debug fast path sections
626 * that printk is not appropriate for. By scattering in various
627 * printk like tracing in the code, a developer can quickly see
628 * where problems are occurring.
630 * This is intended as a debugging tool for the developer only.
631 * Please refrain from leaving trace_puts scattered around in
632 * your code. (Extra memory is used for special buffers that are
633 * allocated when trace_puts() is used)
635 * Returns: 0 if nothing was written, positive # if string was.
636 * (1 when __trace_bputs is used, strlen(str) when __trace_puts is used)
639 #define trace_puts(str) ({ \
640 static const char *trace_printk_fmt \
641 __attribute__((section("__trace_printk_fmt"))) = \
642 __builtin_constant_p(str) ? str : NULL; \
644 if (__builtin_constant_p(str)) \
645 __trace_bputs(_THIS_IP_, trace_printk_fmt); \
646 else \
647 __trace_puts(_THIS_IP_, str, strlen(str)); \
649 extern int __trace_bputs(unsigned long ip, const char *str);
650 extern int __trace_puts(unsigned long ip, const char *str, int size);
652 extern void trace_dump_stack(int skip);
655 * The double __builtin_constant_p is because gcc will give us an error
656 * if we try to allocate the static variable to fmt if it is not a
657 * constant. Even with the outer if statement.
659 #define ftrace_vprintk(fmt, vargs) \
660 do { \
661 if (__builtin_constant_p(fmt)) { \
662 static const char *trace_printk_fmt \
663 __attribute__((section("__trace_printk_fmt"))) = \
664 __builtin_constant_p(fmt) ? fmt : NULL; \
666 __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \
667 } else \
668 __ftrace_vprintk(_THIS_IP_, fmt, vargs); \
669 } while (0)
671 extern int
672 __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap);
674 extern int
675 __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap);
677 extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode);
678 #else
679 static inline void tracing_start(void) { }
680 static inline void tracing_stop(void) { }
681 static inline void trace_dump_stack(int skip) { }
683 static inline void tracing_on(void) { }
684 static inline void tracing_off(void) { }
685 static inline int tracing_is_on(void) { return 0; }
686 static inline void tracing_snapshot(void) { }
687 static inline void tracing_snapshot_alloc(void) { }
689 static inline __printf(1, 2)
690 int trace_printk(const char *fmt, ...)
692 return 0;
694 static inline int
695 ftrace_vprintk(const char *fmt, va_list ap)
697 return 0;
699 static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { }
700 #endif /* CONFIG_TRACING */
703 * min()/max()/clamp() macros that also do
704 * strict type-checking.. See the
705 * "unnecessary" pointer comparison.
707 #define min(x, y) ({ \
708 typeof(x) _min1 = (x); \
709 typeof(y) _min2 = (y); \
710 (void) (&_min1 == &_min2); \
711 _min1 < _min2 ? _min1 : _min2; })
713 #define max(x, y) ({ \
714 typeof(x) _max1 = (x); \
715 typeof(y) _max2 = (y); \
716 (void) (&_max1 == &_max2); \
717 _max1 > _max2 ? _max1 : _max2; })
719 #define min3(x, y, z) min((typeof(x))min(x, y), z)
720 #define max3(x, y, z) max((typeof(x))max(x, y), z)
723 * min_not_zero - return the minimum that is _not_ zero, unless both are zero
724 * @x: value1
725 * @y: value2
727 #define min_not_zero(x, y) ({ \
728 typeof(x) __x = (x); \
729 typeof(y) __y = (y); \
730 __x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); })
733 * clamp - return a value clamped to a given range with strict typechecking
734 * @val: current value
735 * @lo: lowest allowable value
736 * @hi: highest allowable value
738 * This macro does strict typechecking of lo/hi to make sure they are of the
739 * same type as val. See the unnecessary pointer comparisons.
741 #define clamp(val, lo, hi) min((typeof(val))max(val, lo), hi)
744 * ..and if you can't take the strict
745 * types, you can specify one yourself.
747 * Or not use min/max/clamp at all, of course.
749 #define min_t(type, x, y) ({ \
750 type __min1 = (x); \
751 type __min2 = (y); \
752 __min1 < __min2 ? __min1: __min2; })
754 #define max_t(type, x, y) ({ \
755 type __max1 = (x); \
756 type __max2 = (y); \
757 __max1 > __max2 ? __max1: __max2; })
760 * clamp_t - return a value clamped to a given range using a given type
761 * @type: the type of variable to use
762 * @val: current value
763 * @lo: minimum allowable value
764 * @hi: maximum allowable value
766 * This macro does no typechecking and uses temporary variables of type
767 * 'type' to make all the comparisons.
769 #define clamp_t(type, val, lo, hi) min_t(type, max_t(type, val, lo), hi)
772 * clamp_val - return a value clamped to a given range using val's type
773 * @val: current value
774 * @lo: minimum allowable value
775 * @hi: maximum allowable value
777 * This macro does no typechecking and uses temporary variables of whatever
778 * type the input argument 'val' is. This is useful when val is an unsigned
779 * type and min and max are literals that will otherwise be assigned a signed
780 * integer type.
782 #define clamp_val(val, lo, hi) clamp_t(typeof(val), val, lo, hi)
786 * swap - swap value of @a and @b
788 #define swap(a, b) \
789 do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0)
792 * container_of - cast a member of a structure out to the containing structure
793 * @ptr: the pointer to the member.
794 * @type: the type of the container struct this is embedded in.
795 * @member: the name of the member within the struct.
798 #define container_of(ptr, type, member) ({ \
799 const typeof( ((type *)0)->member ) *__mptr = (ptr); \
800 (type *)( (char *)__mptr - offsetof(type,member) );})
802 /* Trap pasters of __FUNCTION__ at compile-time */
803 #define __FUNCTION__ (__func__)
805 /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
806 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
807 # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD
808 #endif
810 /* Permissions on a sysfs file: you didn't miss the 0 prefix did you? */
811 #define VERIFY_OCTAL_PERMISSIONS(perms) \
812 (BUILD_BUG_ON_ZERO((perms) < 0) + \
813 BUILD_BUG_ON_ZERO((perms) > 0777) + \
814 /* User perms >= group perms >= other perms */ \
815 BUILD_BUG_ON_ZERO(((perms) >> 6) < (((perms) >> 3) & 7)) + \
816 BUILD_BUG_ON_ZERO((((perms) >> 3) & 7) < ((perms) & 7)) + \
817 /* Other writable? Generally considered a bad idea. */ \
818 BUILD_BUG_ON_ZERO((perms) & 2) + \
819 (perms))
820 #endif