blob: d6320a3e8def0fc22a9595d8ff03f52c08983404 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001#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>
David Howellsf0d1b0b2006-12-08 02:37:49 -080016#include <linux/log2.h>
Andrew Mortone0deaff42008-07-25 01:45:24 -070017#include <linux/typecheck.h>
Dave Young717115e2008-07-25 01:45:58 -070018#include <linux/ratelimit.h>
Jason Barone9d376f2009-02-05 11:51:38 -050019#include <linux/dynamic_debug.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070020#include <asm/byteorder.h>
21#include <asm/bug.h>
22
Roman Zippel3eb3c742007-01-10 14:45:28 +010023extern const char linux_banner[];
24extern const char linux_proc_banner[];
25
Zhang, Yanmin44f564a2008-04-29 01:00:55 -070026#define USHORT_MAX ((u16)(~0U))
27#define SHORT_MAX ((s16)(USHORT_MAX>>1))
28#define SHORT_MIN (-SHORT_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
Linus Torvalds2ea58142006-11-26 19:05:22 -080041#define ALIGN(x,a) __ALIGN_MASK(x,(typeof(x))(a)-1)
42#define __ALIGN_MASK(x,mask) (((x)+(mask))&~(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
Jan Beulich4552d5d2006-06-26 13:57:28 +020048#define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))
Steven Whitehouse930631e2006-09-25 23:32:40 -070049#define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
David Howellsb4cac1a2006-07-10 04:44:54 -070050#define roundup(x, y) ((((x) + ((y) - 1)) / (y)) * (y))
Darrick J. Wong9fe06082009-01-06 14:40:51 -080051#define DIV_ROUND_CLOSEST(x, divisor)( \
52{ \
53 typeof(divisor) __divisor = divisor; \
54 (((x) + ((__divisor) / 2)) / (__divisor)); \
55} \
56)
Linus Torvalds1da177e2005-04-16 15:20:36 -070057
Eduard - Gabriel Munteanuca31e142008-07-05 12:14:23 +030058#define _RET_IP_ (unsigned long)__builtin_return_address(0)
59#define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; })
60
Bartlomiej Zolnierkiewicz90c699a2009-06-19 08:08:50 +020061#ifdef CONFIG_LBDAF
Jens Axboe2da96ac2007-10-12 12:40:38 +020062# 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
Andrew Morton218e1802007-05-10 03:15:18 -070075/**
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
Joerg Roedel204b8852008-07-29 22:33:42 -070085/**
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
Linus Torvalds1da177e2005-04-16 15:20:36 -070091#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
Linus Torvaldse28d7132009-06-16 11:02:28 -0700100/* Use the default kernel loglevel */
101#define KERN_DEFAULT "<d>"
Ingo Molnar47492522007-10-16 23:30:29 -0700102/*
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 */
Linus Torvalds5fd29d62009-06-16 10:57:02 -0700107#define KERN_CONT "<c>"
Ingo Molnar47492522007-10-16 23:30:29 -0700108
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109extern 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;
akpm@osdl.orgdf2e71f2006-01-09 20:51:37 -0800117struct pt_regs;
118struct user;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700119
Uwe Kleine-König070cb062008-08-12 15:08:59 -0700120#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
Randy Dunlap7106a272008-10-29 14:01:15 -0700127#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
128 void __might_sleep(char *file, int line);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700129/**
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
Jim Cromiee20ec992006-11-30 04:46:13 +0100136 * be bitten later when the calling function happens to sleep when it is not
Linus Torvalds1da177e2005-04-16 15:20:36 -0700137 * supposed to.
138 */
Ingo Molnarf8cbd992005-06-25 14:57:39 -0700139# define might_sleep() \
140 do { __might_sleep(__FILE__, __LINE__); might_resched(); } while (0)
141#else
142# define might_sleep() do { might_resched(); } while (0)
143#endif
144
Hua Zhong368a5fa2006-06-23 02:05:42 -0700145#define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
Ingo Molnarf8cbd992005-06-25 14:57:39 -0700146
Linus Torvalds1da177e2005-04-16 15:20:36 -0700147#define abs(x) ({ \
148 int __x = (x); \
149 (__x < 0) ? -__x : __x; \
150 })
151
Nick Piggin3ee1afa2008-09-10 13:37:17 +0200152#ifdef CONFIG_PROVE_LOCKING
153void might_fault(void);
154#else
155static inline void might_fault(void)
156{
157 might_sleep();
158}
159#endif
160
Alan Sterne041c682006-03-27 01:16:30 -0800161extern struct atomic_notifier_head panic_notifier_list;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700162extern long (*panic_blink)(long time);
163NORET_TYPE void panic(const char * fmt, ...)
Andi Kleena586df02007-07-21 17:10:00 +0200164 __attribute__ ((NORET_AND format (printf, 1, 2))) __cold;
Andrew Mortondd287792006-03-23 03:00:57 -0800165extern void oops_enter(void);
166extern void oops_exit(void);
167extern int oops_may_print(void);
Harvey Harrisonec701582008-02-08 04:19:55 -0800168NORET_TYPE void do_exit(long error_code)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700169 ATTRIB_NORET;
170NORET_TYPE void complete_and_exit(struct completion *, long)
171 ATTRIB_NORET;
172extern unsigned long simple_strtoul(const char *,char **,unsigned int);
173extern long simple_strtol(const char *,char **,unsigned int);
174extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
175extern long long simple_strtoll(const char *,char **,unsigned int);
Yi Yang06b2a762008-02-08 04:21:57 -0800176extern int strict_strtoul(const char *, unsigned int, unsigned long *);
177extern int strict_strtol(const char *, unsigned int, long *);
178extern int strict_strtoull(const char *, unsigned int, unsigned long long *);
179extern int strict_strtoll(const char *, unsigned int, long long *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700180extern int sprintf(char * buf, const char * fmt, ...)
181 __attribute__ ((format (printf, 2, 3)));
182extern int vsprintf(char *buf, const char *, va_list)
183 __attribute__ ((format (printf, 2, 0)));
184extern int snprintf(char * buf, size_t size, const char * fmt, ...)
185 __attribute__ ((format (printf, 3, 4)));
186extern int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
187 __attribute__ ((format (printf, 3, 0)));
188extern int scnprintf(char * buf, size_t size, const char * fmt, ...)
189 __attribute__ ((format (printf, 3, 4)));
190extern int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
191 __attribute__ ((format (printf, 3, 0)));
Jeremy Fitzhardingee9059142006-06-25 05:49:17 -0700192extern char *kasprintf(gfp_t gfp, const char *fmt, ...)
193 __attribute__ ((format (printf, 2, 3)));
Jeremy Fitzhardinge11443ec2007-04-30 15:09:56 -0700194extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700195
196extern int sscanf(const char *, const char *, ...)
197 __attribute__ ((format (scanf, 2, 3)));
198extern int vsscanf(const char *, const char *, va_list)
199 __attribute__ ((format (scanf, 2, 0)));
200
201extern int get_option(char **str, int *pint);
202extern char *get_options(const char *str, int nints, int *ints);
Jeremy Fitzhardinged974ae32008-07-24 16:27:46 -0700203extern unsigned long long memparse(const char *ptr, char **retptr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204
Trent Piepho5e376612006-05-15 09:44:06 -0700205extern int core_kernel_text(unsigned long addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700206extern int __kernel_text_address(unsigned long addr);
207extern int kernel_text_address(unsigned long addr);
Arjan van de Venab7476c2008-08-15 15:29:38 -0700208extern int func_ptr_is_kernel_text(void *ptr);
Arjan van de Venab7476c2008-08-15 15:29:38 -0700209
Eric W. Biederman04a2e6a2007-02-12 00:52:56 -0800210struct pid;
211extern struct pid *session_of_pgrp(struct pid *pgrp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700212
Thomas Renningera0ad05c2008-09-01 14:27:02 +0200213/*
214 * FW_BUG
215 * Add this to a message where you are sure the firmware is buggy or behaves
216 * really stupid or out of spec. Be aware that the responsible BIOS developer
217 * should be able to fix this issue or at least get a concrete idea of the
218 * problem by reading your message without the need of looking at the kernel
219 * code.
220 *
221 * Use it for definite and high priority BIOS bugs.
222 *
223 * FW_WARN
224 * Use it for not that clear (e.g. could the kernel messed up things already?)
225 * and medium priority BIOS bugs.
226 *
227 * FW_INFO
228 * Use this one if you want to tell the user or vendor about something
229 * suspicious, but generally harmless related to the firmware.
230 *
231 * Use it for information or very low priority BIOS bugs.
232 */
233#define FW_BUG "[Firmware Bug]: "
234#define FW_WARN "[Firmware Warn]: "
235#define FW_INFO "[Firmware Info]: "
236
Matt Mackalld59745c2005-05-01 08:59:02 -0700237#ifdef CONFIG_PRINTK
Linus Torvalds1da177e2005-04-16 15:20:36 -0700238asmlinkage int vprintk(const char *fmt, va_list args)
239 __attribute__ ((format (printf, 1, 0)));
240asmlinkage int printk(const char * fmt, ...)
Andi Kleena586df02007-07-21 17:10:00 +0200241 __attribute__ ((format (printf, 1, 2))) __cold;
Joe Perches7ef3d2f2008-02-08 04:21:25 -0800242
Dave Young717115e2008-07-25 01:45:58 -0700243extern struct ratelimit_state printk_ratelimit_state;
Joe Perches7ef3d2f2008-02-08 04:21:25 -0800244extern int printk_ratelimit(void);
Joe Perches7ef3d2f2008-02-08 04:21:25 -0800245extern bool printk_timed_ratelimit(unsigned long *caller_jiffies,
246 unsigned int interval_msec);
Ingo Molnarf036be92009-02-05 13:45:43 +0100247
248/*
249 * Print a one-time message (analogous to WARN_ONCE() et al):
250 */
251#define printk_once(x...) ({ \
252 static int __print_once = 1; \
253 \
254 if (__print_once) { \
255 __print_once = 0; \
256 printk(x); \
257 } \
258})
259
Neil Horman04d491a2009-04-02 16:58:57 -0700260void log_buf_kexec_setup(void);
Matt Mackalld59745c2005-05-01 08:59:02 -0700261#else
262static inline int vprintk(const char *s, va_list args)
263 __attribute__ ((format (printf, 1, 0)));
264static inline int vprintk(const char *s, va_list args) { return 0; }
265static inline int printk(const char *s, ...)
266 __attribute__ ((format (printf, 1, 2)));
Andi Kleena586df02007-07-21 17:10:00 +0200267static inline int __cold printk(const char *s, ...) { return 0; }
Joe Perches7ef3d2f2008-02-08 04:21:25 -0800268static inline int printk_ratelimit(void) { return 0; }
Joe Perches7ef3d2f2008-02-08 04:21:25 -0800269static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies, \
270 unsigned int interval_msec) \
271 { return false; }
Ingo Molnarf036be92009-02-05 13:45:43 +0100272
273/* No effect, but we still get type checking even in the !PRINTK case: */
274#define printk_once(x...) printk(x)
275
Neil Horman04d491a2009-04-02 16:58:57 -0700276static inline void log_buf_kexec_setup(void)
277{
278}
Matt Mackalld59745c2005-05-01 08:59:02 -0700279#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700280
Ingo Molnarced9cd42008-08-11 14:38:12 +0200281extern int printk_needs_cpu(int cpu);
282extern void printk_tick(void);
283
Jiri Slabye17ba732008-05-12 15:44:40 +0200284extern void asmlinkage __attribute__((format(printf, 1, 2)))
Ingo Molnar076f9772008-01-30 13:33:06 +0100285 early_printk(const char *fmt, ...);
286
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287unsigned long int_sqrt(unsigned long);
288
Linus Torvalds1da177e2005-04-16 15:20:36 -0700289static inline void console_silent(void)
290{
291 console_loglevel = 0;
292}
293
294static inline void console_verbose(void)
295{
296 if (console_loglevel)
297 console_loglevel = 15;
298}
299
300extern void bust_spinlocks(int yes);
Kirill Korotaeve3e8a752007-02-10 01:46:19 -0800301extern void wake_up_klogd(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700302extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */
Adrian Bunkaa727102006-04-10 22:53:59 -0700303extern int panic_timeout;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304extern int panic_on_oops;
Don Zickus8da5add2006-09-26 10:52:27 +0200305extern int panic_on_unrecovered_nmi;
Kurt Garloff5211a242009-06-24 14:32:11 -0700306extern int panic_on_io_nmi;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700307extern const char *print_tainted(void);
Andi Kleen25ddbb12008-10-15 22:01:41 -0700308extern void add_taint(unsigned flag);
309extern int test_taint(unsigned flag);
310extern unsigned long get_taint(void);
David Howellsb920de12008-02-08 04:19:31 -0800311extern int root_mountflags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700312
313/* Values used for system_state */
314extern enum system_states {
315 SYSTEM_BOOTING,
316 SYSTEM_RUNNING,
317 SYSTEM_HALT,
318 SYSTEM_POWER_OFF,
319 SYSTEM_RESTART,
Alexey Starikovskiy729b4d42005-12-01 04:29:00 -0500320 SYSTEM_SUSPEND_DISK,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700321} system_state;
322
Andi Kleen25ddbb12008-10-15 22:01:41 -0700323#define TAINT_PROPRIETARY_MODULE 0
324#define TAINT_FORCED_MODULE 1
325#define TAINT_UNSAFE_SMP 2
326#define TAINT_FORCED_RMMOD 3
327#define TAINT_MACHINE_CHECK 4
328#define TAINT_BAD_PAGE 5
329#define TAINT_USER 6
330#define TAINT_DIE 7
331#define TAINT_OVERRIDDEN_ACPI_TABLE 8
332#define TAINT_WARN 9
Linus Torvalds26e9a392008-10-17 09:50:12 -0700333#define TAINT_CRAP 10
Linus Torvalds1da177e2005-04-16 15:20:36 -0700334
Andi Kleena586df02007-07-21 17:10:00 +0200335extern void dump_stack(void) __cold;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700336
Randy Dunlap99eaf3c2007-05-10 22:22:39 -0700337enum {
338 DUMP_PREFIX_NONE,
339 DUMP_PREFIX_ADDRESS,
340 DUMP_PREFIX_OFFSET
341};
Randy Dunlapc7909232007-06-08 13:47:04 -0700342extern void hex_dump_to_buffer(const void *buf, size_t len,
343 int rowsize, int groupsize,
344 char *linebuf, size_t linebuflen, bool ascii);
345extern void print_hex_dump(const char *level, const char *prefix_str,
346 int prefix_type, int rowsize, int groupsize,
Artem Bityutskiy6a0ed912007-08-07 23:43:14 +0300347 const void *buf, size_t len, bool ascii);
Randy Dunlapc7909232007-06-08 13:47:04 -0700348extern void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
Alan Sterneb9a9a52007-08-10 13:01:07 -0700349 const void *buf, size_t len);
Harvey Harrison3fc95772008-05-14 16:05:49 -0700350
351extern const char hex_asc[];
352#define hex_asc_lo(x) hex_asc[((x) & 0x0f)]
353#define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4]
354
355static inline char *pack_hex_byte(char *buf, u8 byte)
356{
357 *buf++ = hex_asc_hi(byte);
358 *buf++ = hex_asc_lo(byte);
359 return buf;
360}
Randy Dunlap99eaf3c2007-05-10 22:22:39 -0700361
Martin Schwidefskyd091c2f2008-11-12 21:16:43 +0100362#ifndef pr_fmt
363#define pr_fmt(fmt) fmt
364#endif
365
366#define pr_emerg(fmt, ...) \
367 printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
368#define pr_alert(fmt, ...) \
369 printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
370#define pr_crit(fmt, ...) \
371 printk(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
372#define pr_err(fmt, ...) \
373 printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
374#define pr_warning(fmt, ...) \
375 printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
376#define pr_notice(fmt, ...) \
377 printk(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
378#define pr_info(fmt, ...) \
379 printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
Cyrill Gorcunov311d0762009-03-31 15:23:51 -0700380#define pr_cont(fmt, ...) \
381 printk(KERN_CONT fmt, ##__VA_ARGS__)
Emil Medve1f7c8232007-10-16 23:29:48 -0700382
Michael Ellerman4ccb4572009-04-09 14:48:24 -0700383/* pr_devel() should produce zero code unless DEBUG is defined */
384#ifdef DEBUG
385#define pr_devel(fmt, ...) \
386 printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
387#else
388#define pr_devel(fmt, ...) \
389 ({ if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); 0; })
390#endif
391
Pavel Machek1cc6daf2006-08-08 01:37:15 +0200392/* If you are writing a driver, please use dev_dbg instead */
Cornelia Huckd0d85ff2008-12-04 16:55:47 +0100393#if defined(DEBUG)
394#define pr_debug(fmt, ...) \
395 printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
Jason Barone9d376f2009-02-05 11:51:38 -0500396#elif defined(CONFIG_DYNAMIC_DEBUG)
Greg Bankse6e66b02009-03-11 21:07:28 +1100397/* dynamic_pr_debug() uses pr_fmt() internally so we don't need it here */
Jason Baron346e15b2008-08-12 16:46:19 -0400398#define pr_debug(fmt, ...) do { \
Greg Bankse6e66b02009-03-11 21:07:28 +1100399 dynamic_pr_debug(fmt, ##__VA_ARGS__); \
Jason Baron346e15b2008-08-12 16:46:19 -0400400 } while (0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700401#else
Martin Schwidefskyd091c2f2008-11-12 21:16:43 +0100402#define pr_debug(fmt, ...) \
403 ({ if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); 0; })
Linus Torvalds1da177e2005-04-16 15:20:36 -0700404#endif
405
Linus Torvalds1da177e2005-04-16 15:20:36 -0700406/*
Ingo Molnar526211b2009-03-05 10:28:45 +0100407 * General tracing related utility functions - trace_printk(),
Steven Rostedt2002c252009-03-05 10:35:56 -0500408 * tracing_on/tracing_off and tracing_start()/tracing_stop
409 *
410 * Use tracing_on/tracing_off when you want to quickly turn on or off
411 * tracing. It simply enables or disables the recording of the trace events.
GeunSik Lim156f5a72009-06-02 15:01:37 +0900412 * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on
Steven Rostedt2002c252009-03-05 10:35:56 -0500413 * file, which gives a means for the kernel and userspace to interact.
414 * Place a tracing_off() in the kernel where you want tracing to end.
415 * From user space, examine the trace, and then echo 1 > tracing_on
416 * to continue tracing.
417 *
418 * tracing_stop/tracing_start has slightly more overhead. It is used
419 * by things like suspend to ram where disabling the recording of the
420 * trace is not enough, but tracing must actually stop because things
421 * like calling smp_processor_id() may crash the system.
422 *
423 * Most likely, you want to use tracing_on/tracing_off.
Ingo Molnar526211b2009-03-05 10:28:45 +0100424 */
Steven Rostedt2002c252009-03-05 10:35:56 -0500425#ifdef CONFIG_RING_BUFFER
426void tracing_on(void);
427void tracing_off(void);
428/* trace_off_permanent stops recording with no way to bring it back */
429void tracing_off_permanent(void);
430int tracing_is_on(void);
431#else
432static inline void tracing_on(void) { }
433static inline void tracing_off(void) { }
434static inline void tracing_off_permanent(void) { }
435static inline int tracing_is_on(void) { return 0; }
436#endif
Ingo Molnar526211b2009-03-05 10:28:45 +0100437#ifdef CONFIG_TRACING
438extern void tracing_start(void);
439extern void tracing_stop(void);
440extern void ftrace_off_permanent(void);
441
442extern void
443ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3);
444
Frederic Weisbecker769b0442009-03-06 17:21:49 +0100445static inline void __attribute__ ((format (printf, 1, 2)))
446____trace_printk_check_format(const char *fmt, ...)
447{
448}
449#define __trace_printk_check_format(fmt, args...) \
450do { \
451 if (0) \
452 ____trace_printk_check_format(fmt, ##args); \
453} while (0)
454
Ingo Molnar526211b2009-03-05 10:28:45 +0100455/**
456 * trace_printk - printf formatting in the ftrace buffer
457 * @fmt: the printf format for printing
458 *
459 * Note: __trace_printk is an internal function for trace_printk and
460 * the @ip is passed in via the trace_printk macro.
461 *
462 * This function allows a kernel developer to debug fast path sections
463 * that printk is not appropriate for. By scattering in various
464 * printk like tracing in the code, a developer can quickly see
465 * where problems are occurring.
466 *
467 * This is intended as a debugging tool for the developer only.
468 * Please refrain from leaving trace_printks scattered around in
469 * your code.
470 */
Frederic Weisbecker769b0442009-03-06 17:21:49 +0100471
472#define trace_printk(fmt, args...) \
473do { \
Frederic Weisbecker769b0442009-03-06 17:21:49 +0100474 __trace_printk_check_format(fmt, ##args); \
Frederic Weisbecker48ead022009-03-12 18:24:49 +0100475 if (__builtin_constant_p(fmt)) { \
476 static const char *trace_printk_fmt \
477 __attribute__((section("__trace_printk_fmt"))) = \
478 __builtin_constant_p(fmt) ? fmt : NULL; \
479 \
480 __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \
481 } else \
482 __trace_printk(_THIS_IP_, fmt, ##args); \
Frederic Weisbecker769b0442009-03-06 17:21:49 +0100483} while (0)
484
Ingo Molnar526211b2009-03-05 10:28:45 +0100485extern int
Frederic Weisbecker48ead022009-03-12 18:24:49 +0100486__trace_bprintk(unsigned long ip, const char *fmt, ...)
487 __attribute__ ((format (printf, 2, 3)));
488
489extern int
Ingo Molnar526211b2009-03-05 10:28:45 +0100490__trace_printk(unsigned long ip, const char *fmt, ...)
491 __attribute__ ((format (printf, 2, 3)));
Frederic Weisbecker769b0442009-03-06 17:21:49 +0100492
Frederic Weisbecker48ead022009-03-12 18:24:49 +0100493/*
494 * The double __builtin_constant_p is because gcc will give us an error
495 * if we try to allocate the static variable to fmt if it is not a
496 * constant. Even with the outer if statement.
497 */
Frederic Weisbecker769b0442009-03-06 17:21:49 +0100498#define ftrace_vprintk(fmt, vargs) \
499do { \
Frederic Weisbecker48ead022009-03-12 18:24:49 +0100500 if (__builtin_constant_p(fmt)) { \
501 static const char *trace_printk_fmt \
502 __attribute__((section("__trace_printk_fmt"))) = \
503 __builtin_constant_p(fmt) ? fmt : NULL; \
Ingo Molnar7bffc232009-03-09 10:11:36 +0100504 \
Frederic Weisbecker48ead022009-03-12 18:24:49 +0100505 __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \
506 } else \
507 __ftrace_vprintk(_THIS_IP_, fmt, vargs); \
Frederic Weisbecker769b0442009-03-06 17:21:49 +0100508} while (0)
509
Ingo Molnar526211b2009-03-05 10:28:45 +0100510extern int
Frederic Weisbecker48ead022009-03-12 18:24:49 +0100511__ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap);
512
513extern int
Ingo Molnar526211b2009-03-05 10:28:45 +0100514__ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap);
Frederic Weisbecker769b0442009-03-06 17:21:49 +0100515
Ingo Molnar526211b2009-03-05 10:28:45 +0100516extern void ftrace_dump(void);
517#else
518static inline void
519ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) { }
520static inline int
521trace_printk(const char *fmt, ...) __attribute__ ((format (printf, 1, 2)));
522
523static inline void tracing_start(void) { }
524static inline void tracing_stop(void) { }
525static inline void ftrace_off_permanent(void) { }
526static inline int
527trace_printk(const char *fmt, ...)
528{
529 return 0;
530}
531static inline int
532ftrace_vprintk(const char *fmt, va_list ap)
533{
534 return 0;
535}
536static inline void ftrace_dump(void) { }
Frederic Weisbecker769b0442009-03-06 17:21:49 +0100537#endif /* CONFIG_TRACING */
Ingo Molnar526211b2009-03-05 10:28:45 +0100538
539/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700540 * Display an IP address in readable format.
541 */
542
543#define NIPQUAD(addr) \
544 ((unsigned char *)&addr)[0], \
545 ((unsigned char *)&addr)[1], \
546 ((unsigned char *)&addr)[2], \
547 ((unsigned char *)&addr)[3]
Joe Perches46b86a22006-01-13 14:29:07 -0800548#define NIPQUAD_FMT "%u.%u.%u.%u"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700549
Linus Torvalds1da177e2005-04-16 15:20:36 -0700550/*
Harvey Harrisonbdf4bba2008-04-30 00:54:55 -0700551 * min()/max()/clamp() macros that also do
Linus Torvalds1da177e2005-04-16 15:20:36 -0700552 * strict type-checking.. See the
553 * "unnecessary" pointer comparison.
554 */
Harvey Harrisonbdf4bba2008-04-30 00:54:55 -0700555#define min(x, y) ({ \
556 typeof(x) _min1 = (x); \
557 typeof(y) _min2 = (y); \
558 (void) (&_min1 == &_min2); \
559 _min1 < _min2 ? _min1 : _min2; })
Linus Torvalds1da177e2005-04-16 15:20:36 -0700560
Harvey Harrisonbdf4bba2008-04-30 00:54:55 -0700561#define max(x, y) ({ \
562 typeof(x) _max1 = (x); \
563 typeof(y) _max2 = (y); \
564 (void) (&_max1 == &_max2); \
565 _max1 > _max2 ? _max1 : _max2; })
566
567/**
568 * clamp - return a value clamped to a given range with strict typechecking
569 * @val: current value
570 * @min: minimum allowable value
571 * @max: maximum allowable value
572 *
573 * This macro does strict typechecking of min/max to make sure they are of the
574 * same type as val. See the unnecessary pointer comparisons.
575 */
576#define clamp(val, min, max) ({ \
577 typeof(val) __val = (val); \
578 typeof(min) __min = (min); \
579 typeof(max) __max = (max); \
580 (void) (&__val == &__min); \
581 (void) (&__val == &__max); \
582 __val = __val < __min ? __min: __val; \
583 __val > __max ? __max: __val; })
Linus Torvalds1da177e2005-04-16 15:20:36 -0700584
585/*
586 * ..and if you can't take the strict
587 * types, you can specify one yourself.
588 *
Harvey Harrisonbdf4bba2008-04-30 00:54:55 -0700589 * Or not use min/max/clamp at all, of course.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700590 */
Harvey Harrisonbdf4bba2008-04-30 00:54:55 -0700591#define min_t(type, x, y) ({ \
592 type __min1 = (x); \
593 type __min2 = (y); \
594 __min1 < __min2 ? __min1: __min2; })
Linus Torvalds1da177e2005-04-16 15:20:36 -0700595
Harvey Harrisonbdf4bba2008-04-30 00:54:55 -0700596#define max_t(type, x, y) ({ \
597 type __max1 = (x); \
598 type __max2 = (y); \
599 __max1 > __max2 ? __max1: __max2; })
600
601/**
602 * clamp_t - return a value clamped to a given range using a given type
603 * @type: the type of variable to use
604 * @val: current value
605 * @min: minimum allowable value
606 * @max: maximum allowable value
607 *
608 * This macro does no typechecking and uses temporary variables of type
609 * 'type' to make all the comparisons.
610 */
611#define clamp_t(type, val, min, max) ({ \
612 type __val = (val); \
613 type __min = (min); \
614 type __max = (max); \
615 __val = __val < __min ? __min: __val; \
616 __val > __max ? __max: __val; })
617
618/**
619 * clamp_val - return a value clamped to a given range using val's type
620 * @val: current value
621 * @min: minimum allowable value
622 * @max: maximum allowable value
623 *
624 * This macro does no typechecking and uses temporary variables of whatever
625 * type the input argument 'val' is. This is useful when val is an unsigned
626 * type and min and max are literals that will otherwise be assigned a signed
627 * integer type.
628 */
629#define clamp_val(val, min, max) ({ \
630 typeof(val) __val = (val); \
631 typeof(val) __min = (min); \
632 typeof(val) __max = (max); \
633 __val = __val < __min ? __min: __val; \
634 __val > __max ? __max: __val; })
Linus Torvalds1da177e2005-04-16 15:20:36 -0700635
Wu Fengguang91f68b72009-01-07 18:09:12 -0800636
637/*
638 * swap - swap value of @a and @b
639 */
Peter Zijlstraac7b9002009-02-04 15:11:59 -0800640#define swap(a, b) \
641 do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0)
Wu Fengguang91f68b72009-01-07 18:09:12 -0800642
Linus Torvalds1da177e2005-04-16 15:20:36 -0700643/**
644 * container_of - cast a member of a structure out to the containing structure
Linus Torvalds1da177e2005-04-16 15:20:36 -0700645 * @ptr: the pointer to the member.
646 * @type: the type of the container struct this is embedded in.
647 * @member: the name of the member within the struct.
648 *
649 */
650#define container_of(ptr, type, member) ({ \
Daniel Walker78db2ad2007-05-12 16:28:35 -0700651 const typeof( ((type *)0)->member ) *__mptr = (ptr); \
652 (type *)( (char *)__mptr - offsetof(type,member) );})
Linus Torvalds1da177e2005-04-16 15:20:36 -0700653
Kyle McMartind4d23ad2007-02-10 01:46:00 -0800654struct sysinfo;
655extern int do_sysinfo(struct sysinfo *info);
656
Linus Torvalds1da177e2005-04-16 15:20:36 -0700657#endif /* __KERNEL__ */
658
659#define SI_LOAD_SHIFT 16
660struct sysinfo {
661 long uptime; /* Seconds since boot */
662 unsigned long loads[3]; /* 1, 5, and 15 minute load averages */
663 unsigned long totalram; /* Total usable main memory size */
664 unsigned long freeram; /* Available memory size */
665 unsigned long sharedram; /* Amount of shared memory */
666 unsigned long bufferram; /* Memory used by buffers */
667 unsigned long totalswap; /* Total swap space size */
668 unsigned long freeswap; /* swap space still available */
669 unsigned short procs; /* Number of current processes */
670 unsigned short pad; /* explicit padding for m68k */
671 unsigned long totalhigh; /* Total high memory size */
672 unsigned long freehigh; /* Available high memory size */
673 unsigned int mem_unit; /* Memory unit size in bytes */
674 char _f[20-2*sizeof(long)-sizeof(int)]; /* Padding: libc5 uses this.. */
675};
676
Nikita Danilovc0398ee2005-10-30 15:03:10 -0800677/* Force a compilation error if condition is true */
Andi Kleen921717a2005-09-13 01:25:13 -0700678#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700679
Jan Beulich4552d5d2006-06-26 13:57:28 +0200680/* Force a compilation error if condition is true, but also produce a
681 result (of value 0 and type size_t), so the expression can be used
682 e.g. in a structure initializer (or where-ever else comma expressions
683 aren't permitted). */
684#define BUILD_BUG_ON_ZERO(e) (sizeof(char[1 - 2 * !!(e)]) - 1)
685
Linus Torvalds1da177e2005-04-16 15:20:36 -0700686/* Trap pasters of __FUNCTION__ at compile-time */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700687#define __FUNCTION__ (__func__)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700688
Christoph Lameter08e0f6a2006-09-27 01:50:06 -0700689/* This helps us to avoid #ifdef CONFIG_NUMA */
690#ifdef CONFIG_NUMA
691#define NUMA_BUILD 1
692#else
693#define NUMA_BUILD 0
694#endif
695
Steven Rostedt29e71ab2008-08-14 15:45:10 -0400696/* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
697#ifdef CONFIG_FTRACE_MCOUNT_RECORD
698# define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD
699#endif
700
Linus Torvalds1da177e2005-04-16 15:20:36 -0700701#endif