blob: 645231c373c8a5b5684e806a9d13647d1eb3300e [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001#ifndef _LINUX_KERNEL_H
2#define _LINUX_KERNEL_H
3
H. Peter Anvind8e5dde2012-02-06 16:36:48 -08004#include <linux/sysinfo.h>
5
Linus Torvalds1da177e2005-04-16 15:20:36 -07006/*
7 * 'kernel.h' contains some often-used function prototypes etc
8 */
Alexey Dobriyana79ff732010-04-13 11:21:46 +02009#define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
10#define __ALIGN_KERNEL_MASK(x, mask) (((x) + (mask)) & ~(mask))
Linus Torvalds1da177e2005-04-16 15:20:36 -070011
12#ifdef __KERNEL__
13
14#include <stdarg.h>
15#include <linux/linkage.h>
16#include <linux/stddef.h>
17#include <linux/types.h>
18#include <linux/compiler.h>
19#include <linux/bitops.h>
David Howellsf0d1b0b2006-12-08 02:37:49 -080020#include <linux/log2.h>
Andrew Mortone0deaff42008-07-25 01:45:24 -070021#include <linux/typecheck.h>
Linus Torvalds968ab182010-11-15 13:37:37 -080022#include <linux/printk.h>
Jason Barone9d376f2009-02-05 11:51:38 -050023#include <linux/dynamic_debug.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070024#include <asm/byteorder.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070025
Alexey Dobriyan4be929b2010-05-24 14:33:03 -070026#define USHRT_MAX ((u16)(~0U))
27#define SHRT_MAX ((s16)(USHRT_MAX>>1))
28#define SHRT_MIN ((s16)(-SHRT_MAX - 1))
Linus Torvalds1da177e2005-04-16 15:20:36 -070029#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)
OGAWA Hirofumi111ebb62006-06-23 02:03:26 -070035#define LLONG_MAX ((long long)(~0ULL>>1))
36#define LLONG_MIN (-LLONG_MAX - 1)
37#define ULLONG_MAX (~0ULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -070038
39#define STACK_MAGIC 0xdeadbeef
40
Alexey Dobriyana79ff732010-04-13 11:21:46 +020041#define ALIGN(x, a) __ALIGN_KERNEL((x), (a))
Alexey Dobriyan9f93ff52010-04-13 14:09:15 +020042#define __ALIGN_MASK(x, mask) __ALIGN_KERNEL_MASK((x), (mask))
Matthew Wilcoxa83308e2007-09-11 15:23:47 -070043#define PTR_ALIGN(p, a) ((typeof(p))ALIGN((unsigned long)(p), (a)))
Herbert Xuf10db622008-02-06 01:37:05 -080044#define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0)
Linus Torvalds2ea58142006-11-26 19:05:22 -080045
Rusty Russellc5e631cf2007-05-06 14:51:05 -070046#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
47
Yinghai Lu9b3be9f2010-02-10 01:20:29 -080048/*
49 * This looks more complex than it should be. But we need to
50 * get the type for the ~ right in round_down (it needs to be
51 * as wide as the result!), and we want to evaluate the macro
52 * arguments just once each.
53 */
54#define __round_mask(x, y) ((__typeof__(x))((y)-1))
55#define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1)
56#define round_down(x, y) ((x) & ~__round_mask(x, y))
57
Jan Beulich4552d5d2006-06-26 13:57:28 +020058#define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))
Steven Whitehouse930631e2006-09-25 23:32:40 -070059#define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
Nicholas Bellinger36a26c62011-07-26 00:35:26 -070060#define DIV_ROUND_UP_ULL(ll,d) \
61 ({ unsigned long long _tmp = (ll)+(d)-1; do_div(_tmp, d); _tmp; })
62
63#if BITS_PER_LONG == 32
64# define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP_ULL(ll, d)
65#else
66# define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP(ll,d)
67#endif
James Morris074e61e2010-11-10 09:01:31 +110068
69/* The `const' in roundup() prevents gcc-3.3 from calling __divdi3 */
Eric Parisb28efd52010-10-13 17:50:08 -040070#define roundup(x, y) ( \
71{ \
Tetsuo Handa6070bf32010-11-08 11:20:49 +090072 const typeof(y) __y = y; \
Eric Parisb28efd52010-10-13 17:50:08 -040073 (((x) + (__y - 1)) / __y) * __y; \
74} \
75)
Eric Paris686a0f32010-10-13 17:50:02 -040076#define rounddown(x, y) ( \
77{ \
78 typeof(x) __x = (x); \
79 __x - (__x % (y)); \
80} \
81)
Darrick J. Wong9fe06082009-01-06 14:40:51 -080082#define DIV_ROUND_CLOSEST(x, divisor)( \
83{ \
84 typeof(divisor) __divisor = divisor; \
85 (((x) + ((__divisor) / 2)) / (__divisor)); \
86} \
87)
Linus Torvalds1da177e2005-04-16 15:20:36 -070088
Salman Qazi9993bc632012-03-09 16:41:01 -080089/*
90 * Multiplies an integer by a fraction, while avoiding unnecessary
91 * overflow or loss of precision.
92 */
93#define mult_frac(x, numer, denom)( \
94{ \
95 typeof(x) quot = (x) / (denom); \
96 typeof(x) rem = (x) % (denom); \
97 (quot * (numer)) + ((rem * (numer)) / (denom)); \
98} \
99)
100
101
Eduard - Gabriel Munteanuca31e142008-07-05 12:14:23 +0300102#define _RET_IP_ (unsigned long)__builtin_return_address(0)
103#define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; })
104
Bartlomiej Zolnierkiewicz90c699a2009-06-19 08:08:50 +0200105#ifdef CONFIG_LBDAF
Jens Axboe2da96ac2007-10-12 12:40:38 +0200106# include <asm/div64.h>
107# define sector_div(a, b) do_div(a, b)
108#else
109# define sector_div(n, b)( \
110{ \
111 int _res; \
112 _res = (n) % (b); \
113 (n) /= (b); \
114 _res; \
115} \
116)
117#endif
118
Andrew Morton218e1802007-05-10 03:15:18 -0700119/**
120 * upper_32_bits - return bits 32-63 of a number
121 * @n: the number we're accessing
122 *
123 * A basic shift-right of a 64- or 32-bit quantity. Use this to suppress
124 * the "right shift count >= width of type" warning when that quantity is
125 * 32-bits.
126 */
127#define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))
128
Joerg Roedel204b8852008-07-29 22:33:42 -0700129/**
130 * lower_32_bits - return bits 0-31 of a number
131 * @n: the number we're accessing
132 */
133#define lower_32_bits(n) ((u32)(n))
134
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135struct completion;
akpm@osdl.orgdf2e71f2006-01-09 20:51:37 -0800136struct pt_regs;
137struct user;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700138
Uwe Kleine-König070cb062008-08-12 15:08:59 -0700139#ifdef CONFIG_PREEMPT_VOLUNTARY
140extern int _cond_resched(void);
141# define might_resched() _cond_resched()
142#else
143# define might_resched() do { } while (0)
144#endif
145
Frederic Weisbeckerd902db12011-06-08 19:31:56 +0200146#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
Simon Kagstromd8948372009-12-23 11:08:18 +0100147 void __might_sleep(const char *file, int line, int preempt_offset);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700148/**
149 * might_sleep - annotation for functions that can sleep
150 *
151 * this macro will print a stack trace if it is executed in an atomic
152 * context (spinlock, irq-handler, ...).
153 *
154 * This is a useful debugging help to be able to catch problems early and not
Jim Cromiee20ec992006-11-30 04:46:13 +0100155 * be bitten later when the calling function happens to sleep when it is not
Linus Torvalds1da177e2005-04-16 15:20:36 -0700156 * supposed to.
157 */
Ingo Molnarf8cbd992005-06-25 14:57:39 -0700158# define might_sleep() \
Frederic Weisbeckere4aafea2009-07-16 15:44:29 +0200159 do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
Ingo Molnarf8cbd992005-06-25 14:57:39 -0700160#else
Simon Kagstromd8948372009-12-23 11:08:18 +0100161 static inline void __might_sleep(const char *file, int line,
162 int preempt_offset) { }
Ingo Molnarf8cbd992005-06-25 14:57:39 -0700163# define might_sleep() do { might_resched(); } while (0)
164#endif
165
Hua Zhong368a5fa2006-06-23 02:05:42 -0700166#define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
Ingo Molnarf8cbd992005-06-25 14:57:39 -0700167
Andrew Morton71a90482011-01-12 16:59:35 -0800168/*
169 * abs() handles unsigned and signed longs, ints, shorts and chars. For all
170 * input types abs() returns a signed long.
171 * abs() should not be used for 64-bit types (s64, u64, long long) - use abs64()
172 * for those.
173 */
174#define abs(x) ({ \
175 long ret; \
176 if (sizeof(x) == sizeof(long)) { \
177 long __x = (x); \
178 ret = (__x < 0) ? -__x : __x; \
179 } else { \
180 int __x = (x); \
181 ret = (__x < 0) ? -__x : __x; \
182 } \
183 ret; \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700184 })
185
Brian Behlendorf658716d2010-10-26 14:23:10 -0700186#define abs64(x) ({ \
187 s64 __x = (x); \
188 (__x < 0) ? -__x : __x; \
189 })
190
Nick Piggin3ee1afa2008-09-10 13:37:17 +0200191#ifdef CONFIG_PROVE_LOCKING
192void might_fault(void);
193#else
194static inline void might_fault(void)
195{
196 might_sleep();
197}
198#endif
199
Alan Sterne041c682006-03-27 01:16:30 -0800200extern struct atomic_notifier_head panic_notifier_list;
TAMUKI Shoichic7ff0d92010-08-10 18:03:28 -0700201extern long (*panic_blink)(int state);
Joe Perches9402c952012-01-12 17:17:17 -0800202__printf(1, 2)
Joe Perches4da47852012-01-12 17:17:13 -0800203void panic(const char *fmt, ...)
Joe Perchesff2d8b12012-01-12 17:17:21 -0800204 __noreturn __cold;
Andrew Mortondd287792006-03-23 03:00:57 -0800205extern void oops_enter(void);
206extern void oops_exit(void);
Anton Blanchard863a6042010-08-10 18:03:30 -0700207void print_oops_end_marker(void);
Andrew Mortondd287792006-03-23 03:00:57 -0800208extern int oops_may_print(void);
Joe Perches9402c952012-01-12 17:17:17 -0800209void do_exit(long error_code)
Joe Perchesff2d8b12012-01-12 17:17:21 -0800210 __noreturn;
Joe Perches9402c952012-01-12 17:17:17 -0800211void complete_and_exit(struct completion *, long)
Joe Perchesff2d8b12012-01-12 17:17:21 -0800212 __noreturn;
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700213
214/* Internal, do not use. */
215int __must_check _kstrtoul(const char *s, unsigned int base, unsigned long *res);
216int __must_check _kstrtol(const char *s, unsigned int base, long *res);
217
218int __must_check kstrtoull(const char *s, unsigned int base, unsigned long long *res);
219int __must_check kstrtoll(const char *s, unsigned int base, long long *res);
220static inline int __must_check kstrtoul(const char *s, unsigned int base, unsigned long *res)
221{
222 /*
223 * We want to shortcut function call, but
224 * __builtin_types_compatible_p(unsigned long, unsigned long long) = 0.
225 */
226 if (sizeof(unsigned long) == sizeof(unsigned long long) &&
227 __alignof__(unsigned long) == __alignof__(unsigned long long))
228 return kstrtoull(s, base, (unsigned long long *)res);
229 else
230 return _kstrtoul(s, base, res);
231}
232
233static inline int __must_check kstrtol(const char *s, unsigned int base, long *res)
234{
235 /*
236 * We want to shortcut function call, but
237 * __builtin_types_compatible_p(long, long long) = 0.
238 */
239 if (sizeof(long) == sizeof(long long) &&
240 __alignof__(long) == __alignof__(long long))
241 return kstrtoll(s, base, (long long *)res);
242 else
243 return _kstrtol(s, base, res);
244}
245
246int __must_check kstrtouint(const char *s, unsigned int base, unsigned int *res);
247int __must_check kstrtoint(const char *s, unsigned int base, int *res);
248
249static inline int __must_check kstrtou64(const char *s, unsigned int base, u64 *res)
250{
251 return kstrtoull(s, base, res);
252}
253
254static inline int __must_check kstrtos64(const char *s, unsigned int base, s64 *res)
255{
256 return kstrtoll(s, base, res);
257}
258
259static inline int __must_check kstrtou32(const char *s, unsigned int base, u32 *res)
260{
261 return kstrtouint(s, base, res);
262}
263
264static inline int __must_check kstrtos32(const char *s, unsigned int base, s32 *res)
265{
266 return kstrtoint(s, base, res);
267}
268
269int __must_check kstrtou16(const char *s, unsigned int base, u16 *res);
270int __must_check kstrtos16(const char *s, unsigned int base, s16 *res);
271int __must_check kstrtou8(const char *s, unsigned int base, u8 *res);
272int __must_check kstrtos8(const char *s, unsigned int base, s8 *res);
273
Alexey Dobriyanc196e322011-05-24 17:13:31 -0700274int __must_check kstrtoull_from_user(const char __user *s, size_t count, unsigned int base, unsigned long long *res);
275int __must_check kstrtoll_from_user(const char __user *s, size_t count, unsigned int base, long long *res);
276int __must_check kstrtoul_from_user(const char __user *s, size_t count, unsigned int base, unsigned long *res);
277int __must_check kstrtol_from_user(const char __user *s, size_t count, unsigned int base, long *res);
278int __must_check kstrtouint_from_user(const char __user *s, size_t count, unsigned int base, unsigned int *res);
279int __must_check kstrtoint_from_user(const char __user *s, size_t count, unsigned int base, int *res);
280int __must_check kstrtou16_from_user(const char __user *s, size_t count, unsigned int base, u16 *res);
281int __must_check kstrtos16_from_user(const char __user *s, size_t count, unsigned int base, s16 *res);
282int __must_check kstrtou8_from_user(const char __user *s, size_t count, unsigned int base, u8 *res);
283int __must_check kstrtos8_from_user(const char __user *s, size_t count, unsigned int base, s8 *res);
284
285static inline int __must_check kstrtou64_from_user(const char __user *s, size_t count, unsigned int base, u64 *res)
286{
287 return kstrtoull_from_user(s, count, base, res);
288}
289
290static inline int __must_check kstrtos64_from_user(const char __user *s, size_t count, unsigned int base, s64 *res)
291{
292 return kstrtoll_from_user(s, count, base, res);
293}
294
295static inline int __must_check kstrtou32_from_user(const char __user *s, size_t count, unsigned int base, u32 *res)
296{
297 return kstrtouint_from_user(s, count, base, res);
298}
299
300static inline int __must_check kstrtos32_from_user(const char __user *s, size_t count, unsigned int base, s32 *res)
301{
302 return kstrtoint_from_user(s, count, base, res);
303}
304
Joe Perches67d0a072011-10-31 17:13:10 -0700305/* Obsolete, do not use. Use kstrto<foo> instead */
306
Linus Torvalds1da177e2005-04-16 15:20:36 -0700307extern unsigned long simple_strtoul(const char *,char **,unsigned int);
308extern long simple_strtol(const char *,char **,unsigned int);
309extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
310extern long long simple_strtoll(const char *,char **,unsigned int);
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700311#define strict_strtoul kstrtoul
312#define strict_strtol kstrtol
313#define strict_strtoull kstrtoull
314#define strict_strtoll kstrtoll
315
KAMEZAWA Hiroyuki1ac101a2012-03-23 15:02:54 -0700316extern int num_to_str(char *buf, int size, unsigned long long num);
317
Joe Perches67d0a072011-10-31 17:13:10 -0700318/* lib/printf utilities */
319
Joe Perchesb9075fa2011-10-31 17:11:33 -0700320extern __printf(2, 3) int sprintf(char *buf, const char * fmt, ...);
321extern __printf(2, 0) int vsprintf(char *buf, const char *, va_list);
322extern __printf(3, 4)
323int snprintf(char *buf, size_t size, const char *fmt, ...);
324extern __printf(3, 0)
325int vsnprintf(char *buf, size_t size, const char *fmt, va_list args);
326extern __printf(3, 4)
327int scnprintf(char *buf, size_t size, const char *fmt, ...);
328extern __printf(3, 0)
329int vscnprintf(char *buf, size_t size, const char *fmt, va_list args);
330extern __printf(2, 3)
331char *kasprintf(gfp_t gfp, const char *fmt, ...);
Jeremy Fitzhardinge11443ec2007-04-30 15:09:56 -0700332extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700333
Joe Perches6061d942012-03-23 15:02:16 -0700334extern __scanf(2, 3)
335int sscanf(const char *, const char *, ...);
336extern __scanf(2, 0)
337int vsscanf(const char *, const char *, va_list);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338
339extern int get_option(char **str, int *pint);
340extern char *get_options(const char *str, int nints, int *ints);
Jeremy Fitzhardinged974ae32008-07-24 16:27:46 -0700341extern unsigned long long memparse(const char *ptr, char **retptr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700342
Trent Piepho5e376612006-05-15 09:44:06 -0700343extern int core_kernel_text(unsigned long addr);
Steven Rostedtcdbe61b2011-05-05 21:14:55 -0400344extern int core_kernel_data(unsigned long addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700345extern int __kernel_text_address(unsigned long addr);
346extern int kernel_text_address(unsigned long addr);
Arjan van de Venab7476c2008-08-15 15:29:38 -0700347extern int func_ptr_is_kernel_text(void *ptr);
Arjan van de Venab7476c2008-08-15 15:29:38 -0700348
Eric W. Biederman04a2e6a2007-02-12 00:52:56 -0800349struct pid;
350extern struct pid *session_of_pgrp(struct pid *pgrp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700351
Linus Torvalds1da177e2005-04-16 15:20:36 -0700352unsigned long int_sqrt(unsigned long);
353
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354extern void bust_spinlocks(int yes);
Kirill Korotaeve3e8a752007-02-10 01:46:19 -0800355extern void wake_up_klogd(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */
Adrian Bunkaa727102006-04-10 22:53:59 -0700357extern int panic_timeout;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700358extern int panic_on_oops;
Don Zickus8da5add2006-09-26 10:52:27 +0200359extern int panic_on_unrecovered_nmi;
Kurt Garloff5211a242009-06-24 14:32:11 -0700360extern int panic_on_io_nmi;
Mitsuo Hayasaka55af7792011-11-29 15:08:36 +0900361extern int sysctl_panic_on_stackoverflow;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700362extern const char *print_tainted(void);
Andi Kleen25ddbb12008-10-15 22:01:41 -0700363extern void add_taint(unsigned flag);
364extern int test_taint(unsigned flag);
365extern unsigned long get_taint(void);
David Howellsb920de12008-02-08 04:19:31 -0800366extern int root_mountflags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367
Tejun Heo2ce802f2011-01-20 12:06:35 +0100368extern bool early_boot_irqs_disabled;
369
Linus Torvalds1da177e2005-04-16 15:20:36 -0700370/* Values used for system_state */
371extern enum system_states {
372 SYSTEM_BOOTING,
373 SYSTEM_RUNNING,
374 SYSTEM_HALT,
375 SYSTEM_POWER_OFF,
376 SYSTEM_RESTART,
Alexey Starikovskiy729b4d42005-12-01 04:29:00 -0500377 SYSTEM_SUSPEND_DISK,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700378} system_state;
379
Andi Kleen25ddbb12008-10-15 22:01:41 -0700380#define TAINT_PROPRIETARY_MODULE 0
381#define TAINT_FORCED_MODULE 1
382#define TAINT_UNSAFE_SMP 2
383#define TAINT_FORCED_RMMOD 3
384#define TAINT_MACHINE_CHECK 4
385#define TAINT_BAD_PAGE 5
386#define TAINT_USER 6
387#define TAINT_DIE 7
388#define TAINT_OVERRIDDEN_ACPI_TABLE 8
389#define TAINT_WARN 9
Linus Torvalds26e9a392008-10-17 09:50:12 -0700390#define TAINT_CRAP 10
Ben Hutchings92946bc2010-04-03 19:36:42 +0100391#define TAINT_FIRMWARE_WORKAROUND 11
Ben Hutchings2449b8b2011-10-24 15:12:28 +0200392#define TAINT_OOT_MODULE 12
Linus Torvalds1da177e2005-04-16 15:20:36 -0700393
Harvey Harrison3fc95772008-05-14 16:05:49 -0700394extern const char hex_asc[];
395#define hex_asc_lo(x) hex_asc[((x) & 0x0f)]
396#define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4]
397
Andy Shevchenko55036ba2011-10-31 17:12:41 -0700398static inline char *hex_byte_pack(char *buf, u8 byte)
Harvey Harrison3fc95772008-05-14 16:05:49 -0700399{
400 *buf++ = hex_asc_hi(byte);
401 *buf++ = hex_asc_lo(byte);
402 return buf;
403}
Randy Dunlap99eaf3c2007-05-10 22:22:39 -0700404
Andy Shevchenko55036ba2011-10-31 17:12:41 -0700405static inline char * __deprecated pack_hex_byte(char *buf, u8 byte)
406{
407 return hex_byte_pack(buf, byte);
408}
409
Andy Shevchenko903788892010-05-24 14:33:23 -0700410extern int hex_to_bin(char ch);
Mimi Zoharb7804982011-09-20 11:23:49 -0400411extern int __must_check hex2bin(u8 *dst, const char *src, size_t count);
Andy Shevchenko903788892010-05-24 14:33:23 -0700412
Joe Perches8a64f332009-12-14 18:00:25 -0800413/*
Ingo Molnar526211b2009-03-05 10:28:45 +0100414 * General tracing related utility functions - trace_printk(),
Steven Rostedt2002c252009-03-05 10:35:56 -0500415 * tracing_on/tracing_off and tracing_start()/tracing_stop
416 *
417 * Use tracing_on/tracing_off when you want to quickly turn on or off
418 * tracing. It simply enables or disables the recording of the trace events.
GeunSik Lim156f5a72009-06-02 15:01:37 +0900419 * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on
Steven Rostedt2002c252009-03-05 10:35:56 -0500420 * file, which gives a means for the kernel and userspace to interact.
421 * Place a tracing_off() in the kernel where you want tracing to end.
422 * From user space, examine the trace, and then echo 1 > tracing_on
423 * to continue tracing.
424 *
425 * tracing_stop/tracing_start has slightly more overhead. It is used
426 * by things like suspend to ram where disabling the recording of the
427 * trace is not enough, but tracing must actually stop because things
428 * like calling smp_processor_id() may crash the system.
429 *
430 * Most likely, you want to use tracing_on/tracing_off.
Ingo Molnar526211b2009-03-05 10:28:45 +0100431 */
Steven Rostedt2002c252009-03-05 10:35:56 -0500432#ifdef CONFIG_RING_BUFFER
Steven Rostedt2002c252009-03-05 10:35:56 -0500433/* trace_off_permanent stops recording with no way to bring it back */
434void tracing_off_permanent(void);
Steven Rostedt2002c252009-03-05 10:35:56 -0500435#else
Steven Rostedt2002c252009-03-05 10:35:56 -0500436static inline void tracing_off_permanent(void) { }
Steven Rostedt2002c252009-03-05 10:35:56 -0500437#endif
Frederic Weisbeckercecbca92010-04-18 19:08:41 +0200438
439enum ftrace_dump_mode {
440 DUMP_NONE,
441 DUMP_ALL,
442 DUMP_ORIG,
443};
444
Ingo Molnar526211b2009-03-05 10:28:45 +0100445#ifdef CONFIG_TRACING
Steven Rostedt93d68e52012-03-20 12:28:29 -0400446void tracing_on(void);
447void tracing_off(void);
448int tracing_is_on(void);
449
Ingo Molnar526211b2009-03-05 10:28:45 +0100450extern void tracing_start(void);
451extern void tracing_stop(void);
452extern void ftrace_off_permanent(void);
453
Joe Perchesb9075fa2011-10-31 17:11:33 -0700454static inline __printf(1, 2)
455void ____trace_printk_check_format(const char *fmt, ...)
Frederic Weisbecker769b0442009-03-06 17:21:49 +0100456{
457}
458#define __trace_printk_check_format(fmt, args...) \
459do { \
460 if (0) \
461 ____trace_printk_check_format(fmt, ##args); \
462} while (0)
463
Ingo Molnar526211b2009-03-05 10:28:45 +0100464/**
465 * trace_printk - printf formatting in the ftrace buffer
466 * @fmt: the printf format for printing
467 *
468 * Note: __trace_printk is an internal function for trace_printk and
469 * the @ip is passed in via the trace_printk macro.
470 *
471 * This function allows a kernel developer to debug fast path sections
472 * that printk is not appropriate for. By scattering in various
473 * printk like tracing in the code, a developer can quickly see
474 * where problems are occurring.
475 *
476 * This is intended as a debugging tool for the developer only.
477 * Please refrain from leaving trace_printks scattered around in
478 * your code.
479 */
Frederic Weisbecker769b0442009-03-06 17:21:49 +0100480
481#define trace_printk(fmt, args...) \
482do { \
Frederic Weisbecker769b0442009-03-06 17:21:49 +0100483 __trace_printk_check_format(fmt, ##args); \
Frederic Weisbecker48ead022009-03-12 18:24:49 +0100484 if (__builtin_constant_p(fmt)) { \
485 static const char *trace_printk_fmt \
486 __attribute__((section("__trace_printk_fmt"))) = \
487 __builtin_constant_p(fmt) ? fmt : NULL; \
488 \
489 __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \
490 } else \
491 __trace_printk(_THIS_IP_, fmt, ##args); \
Frederic Weisbecker769b0442009-03-06 17:21:49 +0100492} while (0)
493
Joe Perchesb9075fa2011-10-31 17:11:33 -0700494extern __printf(2, 3)
495int __trace_bprintk(unsigned long ip, const char *fmt, ...);
Frederic Weisbecker48ead022009-03-12 18:24:49 +0100496
Joe Perchesb9075fa2011-10-31 17:11:33 -0700497extern __printf(2, 3)
498int __trace_printk(unsigned long ip, const char *fmt, ...);
Frederic Weisbecker769b0442009-03-06 17:21:49 +0100499
Steven Rostedt03889382009-12-11 09:48:22 -0500500extern void trace_dump_stack(void);
501
Frederic Weisbecker48ead022009-03-12 18:24:49 +0100502/*
503 * The double __builtin_constant_p is because gcc will give us an error
504 * if we try to allocate the static variable to fmt if it is not a
505 * constant. Even with the outer if statement.
506 */
Frederic Weisbecker769b0442009-03-06 17:21:49 +0100507#define ftrace_vprintk(fmt, vargs) \
508do { \
Frederic Weisbecker48ead022009-03-12 18:24:49 +0100509 if (__builtin_constant_p(fmt)) { \
510 static const char *trace_printk_fmt \
511 __attribute__((section("__trace_printk_fmt"))) = \
512 __builtin_constant_p(fmt) ? fmt : NULL; \
Ingo Molnar7bffc232009-03-09 10:11:36 +0100513 \
Frederic Weisbecker48ead022009-03-12 18:24:49 +0100514 __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \
515 } else \
516 __ftrace_vprintk(_THIS_IP_, fmt, vargs); \
Frederic Weisbecker769b0442009-03-06 17:21:49 +0100517} while (0)
518
Ingo Molnar526211b2009-03-05 10:28:45 +0100519extern int
Frederic Weisbecker48ead022009-03-12 18:24:49 +0100520__ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap);
521
522extern int
Ingo Molnar526211b2009-03-05 10:28:45 +0100523__ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap);
Frederic Weisbecker769b0442009-03-06 17:21:49 +0100524
Frederic Weisbeckercecbca92010-04-18 19:08:41 +0200525extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode);
Ingo Molnar526211b2009-03-05 10:28:45 +0100526#else
Joe Perchesb9075fa2011-10-31 17:11:33 -0700527static inline __printf(1, 2)
528int trace_printk(const char *fmt, ...);
Ingo Molnar526211b2009-03-05 10:28:45 +0100529
530static inline void tracing_start(void) { }
531static inline void tracing_stop(void) { }
532static inline void ftrace_off_permanent(void) { }
Steven Rostedte36c5452009-12-14 15:58:33 -0500533static inline void trace_dump_stack(void) { }
Steven Rostedt93d68e52012-03-20 12:28:29 -0400534
535static inline void tracing_on(void) { }
536static inline void tracing_off(void) { }
537static inline int tracing_is_on(void) { return 0; }
538
Ingo Molnar526211b2009-03-05 10:28:45 +0100539static inline int
540trace_printk(const char *fmt, ...)
541{
542 return 0;
543}
544static inline int
545ftrace_vprintk(const char *fmt, va_list ap)
546{
547 return 0;
548}
Frederic Weisbeckercecbca92010-04-18 19:08:41 +0200549static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { }
Frederic Weisbecker769b0442009-03-06 17:21:49 +0100550#endif /* CONFIG_TRACING */
Ingo Molnar526211b2009-03-05 10:28:45 +0100551
552/*
Harvey Harrisonbdf4bba2008-04-30 00:54:55 -0700553 * min()/max()/clamp() macros that also do
Linus Torvalds1da177e2005-04-16 15:20:36 -0700554 * strict type-checking.. See the
555 * "unnecessary" pointer comparison.
556 */
Harvey Harrisonbdf4bba2008-04-30 00:54:55 -0700557#define min(x, y) ({ \
558 typeof(x) _min1 = (x); \
559 typeof(y) _min2 = (y); \
560 (void) (&_min1 == &_min2); \
561 _min1 < _min2 ? _min1 : _min2; })
Linus Torvalds1da177e2005-04-16 15:20:36 -0700562
Harvey Harrisonbdf4bba2008-04-30 00:54:55 -0700563#define max(x, y) ({ \
564 typeof(x) _max1 = (x); \
565 typeof(y) _max2 = (y); \
566 (void) (&_max1 == &_max2); \
567 _max1 > _max2 ? _max1 : _max2; })
568
Hagen Paul Pfeiferf27c85c2010-10-26 14:22:21 -0700569#define min3(x, y, z) ({ \
570 typeof(x) _min1 = (x); \
571 typeof(y) _min2 = (y); \
572 typeof(z) _min3 = (z); \
573 (void) (&_min1 == &_min2); \
574 (void) (&_min1 == &_min3); \
575 _min1 < _min2 ? (_min1 < _min3 ? _min1 : _min3) : \
576 (_min2 < _min3 ? _min2 : _min3); })
577
578#define max3(x, y, z) ({ \
579 typeof(x) _max1 = (x); \
580 typeof(y) _max2 = (y); \
581 typeof(z) _max3 = (z); \
582 (void) (&_max1 == &_max2); \
583 (void) (&_max1 == &_max3); \
584 _max1 > _max2 ? (_max1 > _max3 ? _max1 : _max3) : \
585 (_max2 > _max3 ? _max2 : _max3); })
586
Harvey Harrisonbdf4bba2008-04-30 00:54:55 -0700587/**
Martin K. Petersenc8bf1332010-09-10 20:07:38 +0200588 * min_not_zero - return the minimum that is _not_ zero, unless both are zero
589 * @x: value1
590 * @y: value2
591 */
592#define min_not_zero(x, y) ({ \
593 typeof(x) __x = (x); \
594 typeof(y) __y = (y); \
595 __x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); })
596
597/**
Harvey Harrisonbdf4bba2008-04-30 00:54:55 -0700598 * clamp - return a value clamped to a given range with strict typechecking
599 * @val: current value
600 * @min: minimum allowable value
601 * @max: maximum allowable value
602 *
603 * This macro does strict typechecking of min/max to make sure they are of the
604 * same type as val. See the unnecessary pointer comparisons.
605 */
606#define clamp(val, min, max) ({ \
607 typeof(val) __val = (val); \
608 typeof(min) __min = (min); \
609 typeof(max) __max = (max); \
610 (void) (&__val == &__min); \
611 (void) (&__val == &__max); \
612 __val = __val < __min ? __min: __val; \
613 __val > __max ? __max: __val; })
Linus Torvalds1da177e2005-04-16 15:20:36 -0700614
615/*
616 * ..and if you can't take the strict
617 * types, you can specify one yourself.
618 *
Harvey Harrisonbdf4bba2008-04-30 00:54:55 -0700619 * Or not use min/max/clamp at all, of course.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700620 */
Harvey Harrisonbdf4bba2008-04-30 00:54:55 -0700621#define min_t(type, x, y) ({ \
622 type __min1 = (x); \
623 type __min2 = (y); \
624 __min1 < __min2 ? __min1: __min2; })
Linus Torvalds1da177e2005-04-16 15:20:36 -0700625
Harvey Harrisonbdf4bba2008-04-30 00:54:55 -0700626#define max_t(type, x, y) ({ \
627 type __max1 = (x); \
628 type __max2 = (y); \
629 __max1 > __max2 ? __max1: __max2; })
630
631/**
632 * clamp_t - return a value clamped to a given range using a given type
633 * @type: the type of variable to use
634 * @val: current value
635 * @min: minimum allowable value
636 * @max: maximum allowable value
637 *
638 * This macro does no typechecking and uses temporary variables of type
639 * 'type' to make all the comparisons.
640 */
641#define clamp_t(type, val, min, max) ({ \
642 type __val = (val); \
643 type __min = (min); \
644 type __max = (max); \
645 __val = __val < __min ? __min: __val; \
646 __val > __max ? __max: __val; })
647
648/**
649 * clamp_val - return a value clamped to a given range using val's type
650 * @val: current value
651 * @min: minimum allowable value
652 * @max: maximum allowable value
653 *
654 * This macro does no typechecking and uses temporary variables of whatever
655 * type the input argument 'val' is. This is useful when val is an unsigned
656 * type and min and max are literals that will otherwise be assigned a signed
657 * integer type.
658 */
659#define clamp_val(val, min, max) ({ \
660 typeof(val) __val = (val); \
661 typeof(val) __min = (min); \
662 typeof(val) __max = (max); \
663 __val = __val < __min ? __min: __val; \
664 __val > __max ? __max: __val; })
Linus Torvalds1da177e2005-04-16 15:20:36 -0700665
Wu Fengguang91f68b72009-01-07 18:09:12 -0800666
667/*
668 * swap - swap value of @a and @b
669 */
Peter Zijlstraac7b9002009-02-04 15:11:59 -0800670#define swap(a, b) \
671 do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0)
Wu Fengguang91f68b72009-01-07 18:09:12 -0800672
Linus Torvalds1da177e2005-04-16 15:20:36 -0700673/**
674 * container_of - cast a member of a structure out to the containing structure
Linus Torvalds1da177e2005-04-16 15:20:36 -0700675 * @ptr: the pointer to the member.
676 * @type: the type of the container struct this is embedded in.
677 * @member: the name of the member within the struct.
678 *
679 */
680#define container_of(ptr, type, member) ({ \
Daniel Walker78db2ad2007-05-12 16:28:35 -0700681 const typeof( ((type *)0)->member ) *__mptr = (ptr); \
682 (type *)( (char *)__mptr - offsetof(type,member) );})
Linus Torvalds1da177e2005-04-16 15:20:36 -0700683
Arnaud Lacombeb9d4f422011-07-25 17:13:03 -0700684/* Trap pasters of __FUNCTION__ at compile-time */
685#define __FUNCTION__ (__func__)
686
687/* This helps us to avoid #ifdef CONFIG_NUMA */
688#ifdef CONFIG_NUMA
689#define NUMA_BUILD 1
690#else
691#define NUMA_BUILD 0
692#endif
693
694/* This helps us avoid #ifdef CONFIG_COMPACTION */
695#ifdef CONFIG_COMPACTION
696#define COMPACTION_BUILD 1
697#else
698#define COMPACTION_BUILD 0
699#endif
700
701/* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
702#ifdef CONFIG_FTRACE_MCOUNT_RECORD
703# define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD
704#endif
WANG Cong9d00f922011-07-25 17:13:02 -0700705
WANG Cong9d00f922011-07-25 17:13:02 -0700706extern int do_sysinfo(struct sysinfo *info);
707
708#endif /* __KERNEL__ */
709
Linus Torvalds1da177e2005-04-16 15:20:36 -0700710#endif