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printk boot_delay: rename printk_delay_msec to loops_per_msec
[net-next-2.6.git] / include / linux / kernel.h
CommitLineData
1da177e4
LT
1#ifndef _LINUX_KERNEL_H
2#define _LINUX_KERNEL_H
3
4/*
5 * 'kernel.h' contains some often-used function prototypes etc
6 */
7
8#ifdef __KERNEL__
9
10#include <stdarg.h>
11#include <linux/linkage.h>
12#include <linux/stddef.h>
13#include <linux/types.h>
14#include <linux/compiler.h>
15#include <linux/bitops.h>
f0d1b0b3 16#include <linux/log2.h>
e0deaff4 17#include <linux/typecheck.h>
717115e1 18#include <linux/ratelimit.h>
e9d376f0 19#include <linux/dynamic_debug.h>
1da177e4
LT
20#include <asm/byteorder.h>
21#include <asm/bug.h>
22
3eb3c740
RZ
23extern const char linux_banner[];
24extern const char linux_proc_banner[];
25
44f564a4
ZY
26#define USHORT_MAX ((u16)(~0U))
27#define SHORT_MAX ((s16)(USHORT_MAX>>1))
28#define SHORT_MIN (-SHORT_MAX - 1)
1da177e4
LT
29#define INT_MAX ((int)(~0U>>1))
30#define INT_MIN (-INT_MAX - 1)
31#define UINT_MAX (~0U)
32#define LONG_MAX ((long)(~0UL>>1))
33#define LONG_MIN (-LONG_MAX - 1)
34#define ULONG_MAX (~0UL)
111ebb6e
OH
35#define LLONG_MAX ((long long)(~0ULL>>1))
36#define LLONG_MIN (-LLONG_MAX - 1)
37#define ULLONG_MAX (~0ULL)
1da177e4
LT
38
39#define STACK_MAGIC 0xdeadbeef
40
2ea58144
LT
41#define ALIGN(x,a) __ALIGN_MASK(x,(typeof(x))(a)-1)
42#define __ALIGN_MASK(x,mask) (((x)+(mask))&~(mask))
a83308e6 43#define PTR_ALIGN(p, a) ((typeof(p))ALIGN((unsigned long)(p), (a)))
f10db627 44#define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0)
2ea58144 45
c5e631cf
RR
46#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
47
4552d5dc 48#define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))
930631ed 49#define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
b4cac1a0 50#define roundup(x, y) ((((x) + ((y) - 1)) / (y)) * (y))
9fe06081
DW
51#define DIV_ROUND_CLOSEST(x, divisor)( \
52{ \
53 typeof(divisor) __divisor = divisor; \
54 (((x) + ((__divisor) / 2)) / (__divisor)); \
55} \
56)
1da177e4 57
ca31e146
EGM
58#define _RET_IP_ (unsigned long)__builtin_return_address(0)
59#define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; })
60
90c699a9 61#ifdef CONFIG_LBDAF
2da96acd
JA
62# include <asm/div64.h>
63# define sector_div(a, b) do_div(a, b)
64#else
65# define sector_div(n, b)( \
66{ \
67 int _res; \
68 _res = (n) % (b); \
69 (n) /= (b); \
70 _res; \
71} \
72)
73#endif
74
218e180e
AM
75/**
76 * upper_32_bits - return bits 32-63 of a number
77 * @n: the number we're accessing
78 *
79 * A basic shift-right of a 64- or 32-bit quantity. Use this to suppress
80 * the "right shift count >= width of type" warning when that quantity is
81 * 32-bits.
82 */
83#define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))
84
204b885e
JR
85/**
86 * lower_32_bits - return bits 0-31 of a number
87 * @n: the number we're accessing
88 */
89#define lower_32_bits(n) ((u32)(n))
90
1da177e4
LT
91#define KERN_EMERG "<0>" /* system is unusable */
92#define KERN_ALERT "<1>" /* action must be taken immediately */
93#define KERN_CRIT "<2>" /* critical conditions */
94#define KERN_ERR "<3>" /* error conditions */
95#define KERN_WARNING "<4>" /* warning conditions */
96#define KERN_NOTICE "<5>" /* normal but significant condition */
97#define KERN_INFO "<6>" /* informational */
98#define KERN_DEBUG "<7>" /* debug-level messages */
99
e28d7137
LT
100/* Use the default kernel loglevel */
101#define KERN_DEFAULT "<d>"
47492527
IM
102/*
103 * Annotation for a "continued" line of log printout (only done after a
104 * line that had no enclosing \n). Only to be used by core/arch code
105 * during early bootup (a continued line is not SMP-safe otherwise).
106 */
5fd29d6c 107#define KERN_CONT "<c>"
47492527 108
1da177e4
LT
109extern int console_printk[];
110
111#define console_loglevel (console_printk[0])
112#define default_message_loglevel (console_printk[1])
113#define minimum_console_loglevel (console_printk[2])
114#define default_console_loglevel (console_printk[3])
115
116struct completion;
df2e71fb
AM
117struct pt_regs;
118struct user;
1da177e4 119
070cb065
UKK
120#ifdef CONFIG_PREEMPT_VOLUNTARY
121extern int _cond_resched(void);
122# define might_resched() _cond_resched()
123#else
124# define might_resched() do { } while (0)
125#endif
126
7106a27b 127#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
e4aafea2 128 void __might_sleep(char *file, int line, int preempt_offset);
1da177e4
LT
129/**
130 * might_sleep - annotation for functions that can sleep
131 *
132 * this macro will print a stack trace if it is executed in an atomic
133 * context (spinlock, irq-handler, ...).
134 *
135 * This is a useful debugging help to be able to catch problems early and not
e20ec991 136 * be bitten later when the calling function happens to sleep when it is not
1da177e4
LT
137 * supposed to.
138 */
f8cbd99b 139# define might_sleep() \
e4aafea2 140 do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
1da177e4 141#else
e4aafea2 142 static inline void __might_sleep(char *file, int line, int preempt_offset) { }
f8cbd99b 143# define might_sleep() do { might_resched(); } while (0)
1da177e4
LT
144#endif
145
368a5fa1 146#define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
f8cbd99b 147
1da177e4
LT
148#define abs(x) ({ \
149 int __x = (x); \
150 (__x < 0) ? -__x : __x; \
151 })
152
3ee1afa3
NP
153#ifdef CONFIG_PROVE_LOCKING
154void might_fault(void);
155#else
156static inline void might_fault(void)
157{
158 might_sleep();
159}
160#endif
161
e041c683 162extern struct atomic_notifier_head panic_notifier_list;
1da177e4
LT
163extern long (*panic_blink)(long time);
164NORET_TYPE void panic(const char * fmt, ...)
a586df06 165 __attribute__ ((NORET_AND format (printf, 1, 2))) __cold;
dd287796
AM
166extern void oops_enter(void);
167extern void oops_exit(void);
168extern int oops_may_print(void);
ec701584 169NORET_TYPE void do_exit(long error_code)
1da177e4
LT
170 ATTRIB_NORET;
171NORET_TYPE void complete_and_exit(struct completion *, long)
172 ATTRIB_NORET;
173extern unsigned long simple_strtoul(const char *,char **,unsigned int);
174extern long simple_strtol(const char *,char **,unsigned int);
175extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
176extern long long simple_strtoll(const char *,char **,unsigned int);
06b2a76d
YY
177extern int strict_strtoul(const char *, unsigned int, unsigned long *);
178extern int strict_strtol(const char *, unsigned int, long *);
179extern int strict_strtoull(const char *, unsigned int, unsigned long long *);
180extern int strict_strtoll(const char *, unsigned int, long long *);
1da177e4
LT
181extern int sprintf(char * buf, const char * fmt, ...)
182 __attribute__ ((format (printf, 2, 3)));
183extern int vsprintf(char *buf, const char *, va_list)
184 __attribute__ ((format (printf, 2, 0)));
185extern int snprintf(char * buf, size_t size, const char * fmt, ...)
186 __attribute__ ((format (printf, 3, 4)));
187extern int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
188 __attribute__ ((format (printf, 3, 0)));
189extern int scnprintf(char * buf, size_t size, const char * fmt, ...)
190 __attribute__ ((format (printf, 3, 4)));
191extern int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
192 __attribute__ ((format (printf, 3, 0)));
e905914f
JF
193extern char *kasprintf(gfp_t gfp, const char *fmt, ...)
194 __attribute__ ((format (printf, 2, 3)));
11443ec7 195extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args);
1da177e4
LT
196
197extern int sscanf(const char *, const char *, ...)
198 __attribute__ ((format (scanf, 2, 3)));
199extern int vsscanf(const char *, const char *, va_list)
200 __attribute__ ((format (scanf, 2, 0)));
201
202extern int get_option(char **str, int *pint);
203extern char *get_options(const char *str, int nints, int *ints);
d974ae37 204extern unsigned long long memparse(const char *ptr, char **retptr);
1da177e4 205
5e376613 206extern int core_kernel_text(unsigned long addr);
1da177e4
LT
207extern int __kernel_text_address(unsigned long addr);
208extern int kernel_text_address(unsigned long addr);
ab7476cf 209extern int func_ptr_is_kernel_text(void *ptr);
ab7476cf 210
04a2e6a5
EB
211struct pid;
212extern struct pid *session_of_pgrp(struct pid *pgrp);
1da177e4 213
a0ad05c7
TR
214/*
215 * FW_BUG
216 * Add this to a message where you are sure the firmware is buggy or behaves
217 * really stupid or out of spec. Be aware that the responsible BIOS developer
218 * should be able to fix this issue or at least get a concrete idea of the
219 * problem by reading your message without the need of looking at the kernel
220 * code.
221 *
222 * Use it for definite and high priority BIOS bugs.
223 *
224 * FW_WARN
225 * Use it for not that clear (e.g. could the kernel messed up things already?)
226 * and medium priority BIOS bugs.
227 *
228 * FW_INFO
229 * Use this one if you want to tell the user or vendor about something
230 * suspicious, but generally harmless related to the firmware.
231 *
232 * Use it for information or very low priority BIOS bugs.
233 */
234#define FW_BUG "[Firmware Bug]: "
235#define FW_WARN "[Firmware Warn]: "
236#define FW_INFO "[Firmware Info]: "
237
d59745ce 238#ifdef CONFIG_PRINTK
1da177e4
LT
239asmlinkage int vprintk(const char *fmt, va_list args)
240 __attribute__ ((format (printf, 1, 0)));
241asmlinkage int printk(const char * fmt, ...)
a586df06 242 __attribute__ ((format (printf, 1, 2))) __cold;
7ef3d2fd 243
717115e1 244extern struct ratelimit_state printk_ratelimit_state;
7ef3d2fd 245extern int printk_ratelimit(void);
7ef3d2fd
JP
246extern bool printk_timed_ratelimit(unsigned long *caller_jiffies,
247 unsigned int interval_msec);
f036be96
IM
248
249/*
250 * Print a one-time message (analogous to WARN_ONCE() et al):
251 */
252#define printk_once(x...) ({ \
253 static int __print_once = 1; \
254 \
255 if (__print_once) { \
256 __print_once = 0; \
257 printk(x); \
258 } \
259})
260
04d491ab 261void log_buf_kexec_setup(void);
d59745ce
MM
262#else
263static inline int vprintk(const char *s, va_list args)
264 __attribute__ ((format (printf, 1, 0)));
265static inline int vprintk(const char *s, va_list args) { return 0; }
266static inline int printk(const char *s, ...)
267 __attribute__ ((format (printf, 1, 2)));
a586df06 268static inline int __cold printk(const char *s, ...) { return 0; }
7ef3d2fd 269static inline int printk_ratelimit(void) { return 0; }
7ef3d2fd
JP
270static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies, \
271 unsigned int interval_msec) \
272 { return false; }
f036be96
IM
273
274/* No effect, but we still get type checking even in the !PRINTK case: */
275#define printk_once(x...) printk(x)
276
04d491ab
NH
277static inline void log_buf_kexec_setup(void)
278{
279}
d59745ce 280#endif
1da177e4 281
ced9cd40
IM
282extern int printk_needs_cpu(int cpu);
283extern void printk_tick(void);
284
e17ba73b 285extern void asmlinkage __attribute__((format(printf, 1, 2)))
076f9776
IM
286 early_printk(const char *fmt, ...);
287
1da177e4
LT
288unsigned long int_sqrt(unsigned long);
289
1da177e4
LT
290static inline void console_silent(void)
291{
292 console_loglevel = 0;
293}
294
295static inline void console_verbose(void)
296{
297 if (console_loglevel)
298 console_loglevel = 15;
299}
300
301extern void bust_spinlocks(int yes);
e3e8a75d 302extern void wake_up_klogd(void);
1da177e4 303extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */
aa727107 304extern int panic_timeout;
1da177e4 305extern int panic_on_oops;
8da5adda 306extern int panic_on_unrecovered_nmi;
5211a242 307extern int panic_on_io_nmi;
1da177e4 308extern const char *print_tainted(void);
25ddbb18
AK
309extern void add_taint(unsigned flag);
310extern int test_taint(unsigned flag);
311extern unsigned long get_taint(void);
b920de1b 312extern int root_mountflags;
1da177e4
LT
313
314/* Values used for system_state */
315extern enum system_states {
316 SYSTEM_BOOTING,
317 SYSTEM_RUNNING,
318 SYSTEM_HALT,
319 SYSTEM_POWER_OFF,
320 SYSTEM_RESTART,
729b4d4c 321 SYSTEM_SUSPEND_DISK,
1da177e4
LT
322} system_state;
323
25ddbb18
AK
324#define TAINT_PROPRIETARY_MODULE 0
325#define TAINT_FORCED_MODULE 1
326#define TAINT_UNSAFE_SMP 2
327#define TAINT_FORCED_RMMOD 3
328#define TAINT_MACHINE_CHECK 4
329#define TAINT_BAD_PAGE 5
330#define TAINT_USER 6
331#define TAINT_DIE 7
332#define TAINT_OVERRIDDEN_ACPI_TABLE 8
333#define TAINT_WARN 9
26e9a397 334#define TAINT_CRAP 10
1da177e4 335
a586df06 336extern void dump_stack(void) __cold;
1da177e4 337
99eaf3c4
RD
338enum {
339 DUMP_PREFIX_NONE,
340 DUMP_PREFIX_ADDRESS,
341 DUMP_PREFIX_OFFSET
342};
c7909234
RD
343extern void hex_dump_to_buffer(const void *buf, size_t len,
344 int rowsize, int groupsize,
345 char *linebuf, size_t linebuflen, bool ascii);
346extern void print_hex_dump(const char *level, const char *prefix_str,
347 int prefix_type, int rowsize, int groupsize,
6a0ed91e 348 const void *buf, size_t len, bool ascii);
c7909234 349extern void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
eb9a9a56 350 const void *buf, size_t len);
3fc95772
HH
351
352extern const char hex_asc[];
353#define hex_asc_lo(x) hex_asc[((x) & 0x0f)]
354#define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4]
355
356static inline char *pack_hex_byte(char *buf, u8 byte)
357{
358 *buf++ = hex_asc_hi(byte);
359 *buf++ = hex_asc_lo(byte);
360 return buf;
361}
99eaf3c4 362
d091c2f5
MS
363#ifndef pr_fmt
364#define pr_fmt(fmt) fmt
365#endif
366
367#define pr_emerg(fmt, ...) \
368 printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
369#define pr_alert(fmt, ...) \
370 printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
371#define pr_crit(fmt, ...) \
372 printk(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
373#define pr_err(fmt, ...) \
374 printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
375#define pr_warning(fmt, ...) \
376 printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
377#define pr_notice(fmt, ...) \
378 printk(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
379#define pr_info(fmt, ...) \
380 printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
311d0761
CG
381#define pr_cont(fmt, ...) \
382 printk(KERN_CONT fmt, ##__VA_ARGS__)
1f7c8234 383
4ccb4579
ME
384/* pr_devel() should produce zero code unless DEBUG is defined */
385#ifdef DEBUG
386#define pr_devel(fmt, ...) \
387 printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
388#else
389#define pr_devel(fmt, ...) \
390 ({ if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); 0; })
391#endif
392
1cc6daf2 393/* If you are writing a driver, please use dev_dbg instead */
d0d85ff9
CH
394#if defined(DEBUG)
395#define pr_debug(fmt, ...) \
396 printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
e9d376f0 397#elif defined(CONFIG_DYNAMIC_DEBUG)
e6e66b02 398/* dynamic_pr_debug() uses pr_fmt() internally so we don't need it here */
346e15be 399#define pr_debug(fmt, ...) do { \
e6e66b02 400 dynamic_pr_debug(fmt, ##__VA_ARGS__); \
346e15be 401 } while (0)
1da177e4 402#else
d091c2f5
MS
403#define pr_debug(fmt, ...) \
404 ({ if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); 0; })
1da177e4
LT
405#endif
406
526211bc
IM
407/*
408 * General tracing related utility functions - trace_printk(),
2002c258
SR
409 * tracing_on/tracing_off and tracing_start()/tracing_stop
410 *
411 * Use tracing_on/tracing_off when you want to quickly turn on or off
412 * tracing. It simply enables or disables the recording of the trace events.
156f5a78 413 * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on
2002c258
SR
414 * file, which gives a means for the kernel and userspace to interact.
415 * Place a tracing_off() in the kernel where you want tracing to end.
416 * From user space, examine the trace, and then echo 1 > tracing_on
417 * to continue tracing.
418 *
419 * tracing_stop/tracing_start has slightly more overhead. It is used
420 * by things like suspend to ram where disabling the recording of the
421 * trace is not enough, but tracing must actually stop because things
422 * like calling smp_processor_id() may crash the system.
423 *
424 * Most likely, you want to use tracing_on/tracing_off.
526211bc 425 */
2002c258
SR
426#ifdef CONFIG_RING_BUFFER
427void tracing_on(void);
428void tracing_off(void);
429/* trace_off_permanent stops recording with no way to bring it back */
430void tracing_off_permanent(void);
431int tracing_is_on(void);
432#else
433static inline void tracing_on(void) { }
434static inline void tracing_off(void) { }
435static inline void tracing_off_permanent(void) { }
436static inline int tracing_is_on(void) { return 0; }
437#endif
526211bc
IM
438#ifdef CONFIG_TRACING
439extern void tracing_start(void);
440extern void tracing_stop(void);
441extern void ftrace_off_permanent(void);
442
443extern void
444ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3);
445
769b0441
FW
446static inline void __attribute__ ((format (printf, 1, 2)))
447____trace_printk_check_format(const char *fmt, ...)
448{
449}
450#define __trace_printk_check_format(fmt, args...) \
451do { \
452 if (0) \
453 ____trace_printk_check_format(fmt, ##args); \
454} while (0)
455
526211bc
IM
456/**
457 * trace_printk - printf formatting in the ftrace buffer
458 * @fmt: the printf format for printing
459 *
460 * Note: __trace_printk is an internal function for trace_printk and
461 * the @ip is passed in via the trace_printk macro.
462 *
463 * This function allows a kernel developer to debug fast path sections
464 * that printk is not appropriate for. By scattering in various
465 * printk like tracing in the code, a developer can quickly see
466 * where problems are occurring.
467 *
468 * This is intended as a debugging tool for the developer only.
469 * Please refrain from leaving trace_printks scattered around in
470 * your code.
471 */
769b0441
FW
472
473#define trace_printk(fmt, args...) \
474do { \
769b0441 475 __trace_printk_check_format(fmt, ##args); \
48ead020
FW
476 if (__builtin_constant_p(fmt)) { \
477 static const char *trace_printk_fmt \
478 __attribute__((section("__trace_printk_fmt"))) = \
479 __builtin_constant_p(fmt) ? fmt : NULL; \
480 \
481 __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \
482 } else \
483 __trace_printk(_THIS_IP_, fmt, ##args); \
769b0441
FW
484} while (0)
485
48ead020
FW
486extern int
487__trace_bprintk(unsigned long ip, const char *fmt, ...)
488 __attribute__ ((format (printf, 2, 3)));
489
526211bc
IM
490extern int
491__trace_printk(unsigned long ip, const char *fmt, ...)
492 __attribute__ ((format (printf, 2, 3)));
769b0441 493
48ead020
FW
494/*
495 * The double __builtin_constant_p is because gcc will give us an error
496 * if we try to allocate the static variable to fmt if it is not a
497 * constant. Even with the outer if statement.
498 */
769b0441
FW
499#define ftrace_vprintk(fmt, vargs) \
500do { \
48ead020
FW
501 if (__builtin_constant_p(fmt)) { \
502 static const char *trace_printk_fmt \
503 __attribute__((section("__trace_printk_fmt"))) = \
504 __builtin_constant_p(fmt) ? fmt : NULL; \
7bffc23e 505 \
48ead020
FW
506 __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \
507 } else \
508 __ftrace_vprintk(_THIS_IP_, fmt, vargs); \
769b0441
FW
509} while (0)
510
48ead020
FW
511extern int
512__ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap);
513
526211bc
IM
514extern int
515__ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap);
769b0441 516
526211bc
IM
517extern void ftrace_dump(void);
518#else
519static inline void
520ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) { }
521static inline int
522trace_printk(const char *fmt, ...) __attribute__ ((format (printf, 1, 2)));
523
524static inline void tracing_start(void) { }
525static inline void tracing_stop(void) { }
526static inline void ftrace_off_permanent(void) { }
527static inline int
528trace_printk(const char *fmt, ...)
529{
530 return 0;
531}
532static inline int
533ftrace_vprintk(const char *fmt, va_list ap)
534{
535 return 0;
536}
537static inline void ftrace_dump(void) { }
769b0441 538#endif /* CONFIG_TRACING */
526211bc 539
1da177e4
LT
540/*
541 * Display an IP address in readable format.
542 */
543
544#define NIPQUAD(addr) \
545 ((unsigned char *)&addr)[0], \
546 ((unsigned char *)&addr)[1], \
547 ((unsigned char *)&addr)[2], \
548 ((unsigned char *)&addr)[3]
46b86a2d 549#define NIPQUAD_FMT "%u.%u.%u.%u"
1da177e4 550
1da177e4 551/*
bdf4bbaa 552 * min()/max()/clamp() macros that also do
1da177e4
LT
553 * strict type-checking.. See the
554 * "unnecessary" pointer comparison.
555 */
bdf4bbaa
HH
556#define min(x, y) ({ \
557 typeof(x) _min1 = (x); \
558 typeof(y) _min2 = (y); \
559 (void) (&_min1 == &_min2); \
560 _min1 < _min2 ? _min1 : _min2; })
561
562#define max(x, y) ({ \
563 typeof(x) _max1 = (x); \
564 typeof(y) _max2 = (y); \
565 (void) (&_max1 == &_max2); \
566 _max1 > _max2 ? _max1 : _max2; })
567
568/**
569 * clamp - return a value clamped to a given range with strict typechecking
570 * @val: current value
571 * @min: minimum allowable value
572 * @max: maximum allowable value
573 *
574 * This macro does strict typechecking of min/max to make sure they are of the
575 * same type as val. See the unnecessary pointer comparisons.
576 */
577#define clamp(val, min, max) ({ \
578 typeof(val) __val = (val); \
579 typeof(min) __min = (min); \
580 typeof(max) __max = (max); \
581 (void) (&__val == &__min); \
582 (void) (&__val == &__max); \
583 __val = __val < __min ? __min: __val; \
584 __val > __max ? __max: __val; })
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LT
585
586/*
587 * ..and if you can't take the strict
588 * types, you can specify one yourself.
589 *
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HH
590 * Or not use min/max/clamp at all, of course.
591 */
592#define min_t(type, x, y) ({ \
593 type __min1 = (x); \
594 type __min2 = (y); \
595 __min1 < __min2 ? __min1: __min2; })
596
597#define max_t(type, x, y) ({ \
598 type __max1 = (x); \
599 type __max2 = (y); \
600 __max1 > __max2 ? __max1: __max2; })
601
602/**
603 * clamp_t - return a value clamped to a given range using a given type
604 * @type: the type of variable to use
605 * @val: current value
606 * @min: minimum allowable value
607 * @max: maximum allowable value
608 *
609 * This macro does no typechecking and uses temporary variables of type
610 * 'type' to make all the comparisons.
1da177e4 611 */
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HH
612#define clamp_t(type, val, min, max) ({ \
613 type __val = (val); \
614 type __min = (min); \
615 type __max = (max); \
616 __val = __val < __min ? __min: __val; \
617 __val > __max ? __max: __val; })
1da177e4 618
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HH
619/**
620 * clamp_val - return a value clamped to a given range using val's type
621 * @val: current value
622 * @min: minimum allowable value
623 * @max: maximum allowable value
624 *
625 * This macro does no typechecking and uses temporary variables of whatever
626 * type the input argument 'val' is. This is useful when val is an unsigned
627 * type and min and max are literals that will otherwise be assigned a signed
628 * integer type.
629 */
630#define clamp_val(val, min, max) ({ \
631 typeof(val) __val = (val); \
632 typeof(val) __min = (min); \
633 typeof(val) __max = (max); \
634 __val = __val < __min ? __min: __val; \
635 __val > __max ? __max: __val; })
1da177e4 636
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WF
637
638/*
639 * swap - swap value of @a and @b
640 */
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PZ
641#define swap(a, b) \
642 do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0)
91f68b73 643
1da177e4
LT
644/**
645 * container_of - cast a member of a structure out to the containing structure
1da177e4
LT
646 * @ptr: the pointer to the member.
647 * @type: the type of the container struct this is embedded in.
648 * @member: the name of the member within the struct.
649 *
650 */
651#define container_of(ptr, type, member) ({ \
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DW
652 const typeof( ((type *)0)->member ) *__mptr = (ptr); \
653 (type *)( (char *)__mptr - offsetof(type,member) );})
1da177e4 654
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KM
655struct sysinfo;
656extern int do_sysinfo(struct sysinfo *info);
657
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LT
658#endif /* __KERNEL__ */
659
660#define SI_LOAD_SHIFT 16
661struct sysinfo {
662 long uptime; /* Seconds since boot */
663 unsigned long loads[3]; /* 1, 5, and 15 minute load averages */
664 unsigned long totalram; /* Total usable main memory size */
665 unsigned long freeram; /* Available memory size */
666 unsigned long sharedram; /* Amount of shared memory */
667 unsigned long bufferram; /* Memory used by buffers */
668 unsigned long totalswap; /* Total swap space size */
669 unsigned long freeswap; /* swap space still available */
670 unsigned short procs; /* Number of current processes */
671 unsigned short pad; /* explicit padding for m68k */
672 unsigned long totalhigh; /* Total high memory size */
673 unsigned long freehigh; /* Available high memory size */
674 unsigned int mem_unit; /* Memory unit size in bytes */
675 char _f[20-2*sizeof(long)-sizeof(int)]; /* Padding: libc5 uses this.. */
676};
677
c0398ee6 678/* Force a compilation error if condition is true */
921717a2 679#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
1da177e4 680
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JB
681/* Force a compilation error if condition is true, but also produce a
682 result (of value 0 and type size_t), so the expression can be used
683 e.g. in a structure initializer (or where-ever else comma expressions
684 aren't permitted). */
685#define BUILD_BUG_ON_ZERO(e) (sizeof(char[1 - 2 * !!(e)]) - 1)
686
1da177e4 687/* Trap pasters of __FUNCTION__ at compile-time */
1da177e4 688#define __FUNCTION__ (__func__)
1da177e4 689
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CL
690/* This helps us to avoid #ifdef CONFIG_NUMA */
691#ifdef CONFIG_NUMA
692#define NUMA_BUILD 1
693#else
694#define NUMA_BUILD 0
695#endif
696
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SR
697/* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
698#ifdef CONFIG_FTRACE_MCOUNT_RECORD
699# define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD
700#endif
701
1da177e4 702#endif