Blame view
kernel/spinlock.c
9.79 KB
1da177e4c
|
1 2 3 4 5 |
/* * Copyright (2004) Linus Torvalds * * Author: Zwane Mwaikambo <zwane@fsmlabs.com> * |
fb1c8f93d
|
6 7 8 9 |
* Copyright (2004, 2005) Ingo Molnar * * This file contains the spinlock/rwlock implementations for the * SMP and the DEBUG_SPINLOCK cases. (UP-nondebug inlines them) |
0cb91a229
|
10 11 12 13 14 |
* * Note that some architectures have special knowledge about the * stack frames of these functions in their profile_pc. If you * change anything significant here that could change the stack * frame contact the architecture maintainers. |
1da177e4c
|
15 |
*/ |
1da177e4c
|
16 17 18 19 |
#include <linux/linkage.h> #include <linux/preempt.h> #include <linux/spinlock.h> #include <linux/interrupt.h> |
8a25d5deb
|
20 |
#include <linux/debug_locks.h> |
9984de1a5
|
21 |
#include <linux/export.h> |
1da177e4c
|
22 |
|
8e13c7b77
|
23 24 25 26 27 28 29 30 31 32 33 |
/* * If lockdep is enabled then we use the non-preemption spin-ops * even on CONFIG_PREEMPT, because lockdep assumes that interrupts are * not re-enabled during lock-acquire (which the preempt-spin-ops do): */ #if !defined(CONFIG_GENERIC_LOCKBREAK) || defined(CONFIG_DEBUG_LOCK_ALLOC) /* * The __lock_function inlines are taken from * include/linux/spinlock_api_smp.h */ #else |
c2f21ce2e
|
34 35 |
#define raw_read_can_lock(l) read_can_lock(l) #define raw_write_can_lock(l) write_can_lock(l) |
c14c338cb
|
36 37 38 39 40 41 42 43 44 45 46 47 48 |
/* * Some architectures can relax in favour of the CPU owning the lock. */ #ifndef arch_read_relax # define arch_read_relax(l) cpu_relax() #endif #ifndef arch_write_relax # define arch_write_relax(l) cpu_relax() #endif #ifndef arch_spin_relax # define arch_spin_relax(l) cpu_relax() #endif |
8e13c7b77
|
49 50 51 52 53 54 55 56 57 58 |
/* * We build the __lock_function inlines here. They are too large for * inlining all over the place, but here is only one user per function * which embedds them into the calling _lock_function below. * * This could be a long-held lock. We both prepare to spin for a long * time (making _this_ CPU preemptable if possible), and we also signal * towards that other CPU that it should break the lock ASAP. */ #define BUILD_LOCK_OPS(op, locktype) \ |
9c1721aa4
|
59 |
void __lockfunc __raw_##op##_lock(locktype##_t *lock) \ |
8e13c7b77
|
60 61 62 |
{ \ for (;;) { \ preempt_disable(); \ |
9828ea9d7
|
63 |
if (likely(do_raw_##op##_trylock(lock))) \ |
8e13c7b77
|
64 65 66 67 68 |
break; \ preempt_enable(); \ \ if (!(lock)->break_lock) \ (lock)->break_lock = 1; \ |
c2f21ce2e
|
69 |
while (!raw_##op##_can_lock(lock) && (lock)->break_lock)\ |
0199c4e68
|
70 |
arch_##op##_relax(&lock->raw_lock); \ |
8e13c7b77
|
71 72 73 74 |
} \ (lock)->break_lock = 0; \ } \ \ |
9c1721aa4
|
75 |
unsigned long __lockfunc __raw_##op##_lock_irqsave(locktype##_t *lock) \ |
8e13c7b77
|
76 77 78 79 80 81 |
{ \ unsigned long flags; \ \ for (;;) { \ preempt_disable(); \ local_irq_save(flags); \ |
9828ea9d7
|
82 |
if (likely(do_raw_##op##_trylock(lock))) \ |
8e13c7b77
|
83 84 85 86 87 88 |
break; \ local_irq_restore(flags); \ preempt_enable(); \ \ if (!(lock)->break_lock) \ (lock)->break_lock = 1; \ |
c2f21ce2e
|
89 |
while (!raw_##op##_can_lock(lock) && (lock)->break_lock)\ |
0199c4e68
|
90 |
arch_##op##_relax(&lock->raw_lock); \ |
8e13c7b77
|
91 92 93 94 95 |
} \ (lock)->break_lock = 0; \ return flags; \ } \ \ |
9c1721aa4
|
96 |
void __lockfunc __raw_##op##_lock_irq(locktype##_t *lock) \ |
8e13c7b77
|
97 |
{ \ |
9c1721aa4
|
98 |
_raw_##op##_lock_irqsave(lock); \ |
8e13c7b77
|
99 100 |
} \ \ |
9c1721aa4
|
101 |
void __lockfunc __raw_##op##_lock_bh(locktype##_t *lock) \ |
8e13c7b77
|
102 103 104 105 106 107 108 109 |
{ \ unsigned long flags; \ \ /* */ \ /* Careful: we must exclude softirqs too, hence the */ \ /* irq-disabling. We use the generic preemption-aware */ \ /* function: */ \ /**/ \ |
9c1721aa4
|
110 |
flags = _raw_##op##_lock_irqsave(lock); \ |
8e13c7b77
|
111 112 113 114 115 116 117 118 119 120 121 122 123 |
local_bh_disable(); \ local_irq_restore(flags); \ } \ /* * Build preemption-friendly versions of the following * lock-spinning functions: * * __[spin|read|write]_lock() * __[spin|read|write]_lock_irq() * __[spin|read|write]_lock_irqsave() * __[spin|read|write]_lock_bh() */ |
c2f21ce2e
|
124 |
BUILD_LOCK_OPS(spin, raw_spinlock); |
8e13c7b77
|
125 126 127 128 |
BUILD_LOCK_OPS(read, rwlock); BUILD_LOCK_OPS(write, rwlock); #endif |
6beb00092
|
129 |
#ifndef CONFIG_INLINE_SPIN_TRYLOCK |
9c1721aa4
|
130 |
int __lockfunc _raw_spin_trylock(raw_spinlock_t *lock) |
1da177e4c
|
131 |
{ |
9c1721aa4
|
132 |
return __raw_spin_trylock(lock); |
1da177e4c
|
133 |
} |
9c1721aa4
|
134 |
EXPORT_SYMBOL(_raw_spin_trylock); |
892a7c67c
|
135 |
#endif |
1da177e4c
|
136 |
|
b7b40ade5
|
137 |
#ifndef CONFIG_INLINE_SPIN_TRYLOCK_BH |
9c1721aa4
|
138 |
int __lockfunc _raw_spin_trylock_bh(raw_spinlock_t *lock) |
1da177e4c
|
139 |
{ |
9c1721aa4
|
140 |
return __raw_spin_trylock_bh(lock); |
1da177e4c
|
141 |
} |
9c1721aa4
|
142 |
EXPORT_SYMBOL(_raw_spin_trylock_bh); |
892a7c67c
|
143 |
#endif |
1da177e4c
|
144 |
|
b7b40ade5
|
145 |
#ifndef CONFIG_INLINE_SPIN_LOCK |
9c1721aa4
|
146 |
void __lockfunc _raw_spin_lock(raw_spinlock_t *lock) |
1da177e4c
|
147 |
{ |
9c1721aa4
|
148 |
__raw_spin_lock(lock); |
1da177e4c
|
149 |
} |
9c1721aa4
|
150 |
EXPORT_SYMBOL(_raw_spin_lock); |
892a7c67c
|
151 |
#endif |
1da177e4c
|
152 |
|
6beb00092
|
153 |
#ifndef CONFIG_INLINE_SPIN_LOCK_IRQSAVE |
9c1721aa4
|
154 |
unsigned long __lockfunc _raw_spin_lock_irqsave(raw_spinlock_t *lock) |
1da177e4c
|
155 |
{ |
9c1721aa4
|
156 |
return __raw_spin_lock_irqsave(lock); |
1da177e4c
|
157 |
} |
9c1721aa4
|
158 |
EXPORT_SYMBOL(_raw_spin_lock_irqsave); |
892a7c67c
|
159 |
#endif |
1da177e4c
|
160 |
|
6beb00092
|
161 |
#ifndef CONFIG_INLINE_SPIN_LOCK_IRQ |
9c1721aa4
|
162 |
void __lockfunc _raw_spin_lock_irq(raw_spinlock_t *lock) |
1da177e4c
|
163 |
{ |
9c1721aa4
|
164 |
__raw_spin_lock_irq(lock); |
1da177e4c
|
165 |
} |
9c1721aa4
|
166 |
EXPORT_SYMBOL(_raw_spin_lock_irq); |
892a7c67c
|
167 |
#endif |
1da177e4c
|
168 |
|
6beb00092
|
169 |
#ifndef CONFIG_INLINE_SPIN_LOCK_BH |
9c1721aa4
|
170 |
void __lockfunc _raw_spin_lock_bh(raw_spinlock_t *lock) |
1da177e4c
|
171 |
{ |
9c1721aa4
|
172 |
__raw_spin_lock_bh(lock); |
1da177e4c
|
173 |
} |
9c1721aa4
|
174 |
EXPORT_SYMBOL(_raw_spin_lock_bh); |
892a7c67c
|
175 |
#endif |
1da177e4c
|
176 |
|
e335e3eb8
|
177 |
#ifdef CONFIG_UNINLINE_SPIN_UNLOCK |
9c1721aa4
|
178 |
void __lockfunc _raw_spin_unlock(raw_spinlock_t *lock) |
1da177e4c
|
179 |
{ |
9c1721aa4
|
180 |
__raw_spin_unlock(lock); |
1da177e4c
|
181 |
} |
9c1721aa4
|
182 |
EXPORT_SYMBOL(_raw_spin_unlock); |
892a7c67c
|
183 |
#endif |
1da177e4c
|
184 |
|
b7b40ade5
|
185 |
#ifndef CONFIG_INLINE_SPIN_UNLOCK_IRQRESTORE |
9c1721aa4
|
186 |
void __lockfunc _raw_spin_unlock_irqrestore(raw_spinlock_t *lock, unsigned long flags) |
1da177e4c
|
187 |
{ |
9c1721aa4
|
188 |
__raw_spin_unlock_irqrestore(lock, flags); |
1da177e4c
|
189 |
} |
9c1721aa4
|
190 |
EXPORT_SYMBOL(_raw_spin_unlock_irqrestore); |
892a7c67c
|
191 |
#endif |
1da177e4c
|
192 |
|
b7b40ade5
|
193 |
#ifndef CONFIG_INLINE_SPIN_UNLOCK_IRQ |
9c1721aa4
|
194 |
void __lockfunc _raw_spin_unlock_irq(raw_spinlock_t *lock) |
1da177e4c
|
195 |
{ |
9c1721aa4
|
196 |
__raw_spin_unlock_irq(lock); |
1da177e4c
|
197 |
} |
9c1721aa4
|
198 |
EXPORT_SYMBOL(_raw_spin_unlock_irq); |
892a7c67c
|
199 |
#endif |
1da177e4c
|
200 |
|
b7b40ade5
|
201 |
#ifndef CONFIG_INLINE_SPIN_UNLOCK_BH |
9c1721aa4
|
202 |
void __lockfunc _raw_spin_unlock_bh(raw_spinlock_t *lock) |
1da177e4c
|
203 |
{ |
9c1721aa4
|
204 |
__raw_spin_unlock_bh(lock); |
1da177e4c
|
205 |
} |
9c1721aa4
|
206 |
EXPORT_SYMBOL(_raw_spin_unlock_bh); |
892a7c67c
|
207 |
#endif |
1da177e4c
|
208 |
|
b7b40ade5
|
209 |
#ifndef CONFIG_INLINE_READ_TRYLOCK |
9c1721aa4
|
210 |
int __lockfunc _raw_read_trylock(rwlock_t *lock) |
1da177e4c
|
211 |
{ |
9c1721aa4
|
212 |
return __raw_read_trylock(lock); |
1da177e4c
|
213 |
} |
9c1721aa4
|
214 |
EXPORT_SYMBOL(_raw_read_trylock); |
892a7c67c
|
215 |
#endif |
1da177e4c
|
216 |
|
b7b40ade5
|
217 |
#ifndef CONFIG_INLINE_READ_LOCK |
9c1721aa4
|
218 |
void __lockfunc _raw_read_lock(rwlock_t *lock) |
1da177e4c
|
219 |
{ |
9c1721aa4
|
220 |
__raw_read_lock(lock); |
1da177e4c
|
221 |
} |
9c1721aa4
|
222 |
EXPORT_SYMBOL(_raw_read_lock); |
892a7c67c
|
223 |
#endif |
1da177e4c
|
224 |
|
b7b40ade5
|
225 |
#ifndef CONFIG_INLINE_READ_LOCK_IRQSAVE |
9c1721aa4
|
226 |
unsigned long __lockfunc _raw_read_lock_irqsave(rwlock_t *lock) |
1da177e4c
|
227 |
{ |
9c1721aa4
|
228 |
return __raw_read_lock_irqsave(lock); |
1da177e4c
|
229 |
} |
9c1721aa4
|
230 |
EXPORT_SYMBOL(_raw_read_lock_irqsave); |
892a7c67c
|
231 |
#endif |
1da177e4c
|
232 |
|
b7b40ade5
|
233 |
#ifndef CONFIG_INLINE_READ_LOCK_IRQ |
9c1721aa4
|
234 |
void __lockfunc _raw_read_lock_irq(rwlock_t *lock) |
1da177e4c
|
235 |
{ |
9c1721aa4
|
236 |
__raw_read_lock_irq(lock); |
1da177e4c
|
237 |
} |
9c1721aa4
|
238 |
EXPORT_SYMBOL(_raw_read_lock_irq); |
892a7c67c
|
239 |
#endif |
1da177e4c
|
240 |
|
b7b40ade5
|
241 |
#ifndef CONFIG_INLINE_READ_LOCK_BH |
9c1721aa4
|
242 |
void __lockfunc _raw_read_lock_bh(rwlock_t *lock) |
1da177e4c
|
243 |
{ |
9c1721aa4
|
244 |
__raw_read_lock_bh(lock); |
1da177e4c
|
245 |
} |
9c1721aa4
|
246 |
EXPORT_SYMBOL(_raw_read_lock_bh); |
892a7c67c
|
247 |
#endif |
1da177e4c
|
248 |
|
6beb00092
|
249 |
#ifndef CONFIG_INLINE_READ_UNLOCK |
9c1721aa4
|
250 |
void __lockfunc _raw_read_unlock(rwlock_t *lock) |
1da177e4c
|
251 |
{ |
9c1721aa4
|
252 |
__raw_read_unlock(lock); |
1da177e4c
|
253 |
} |
9c1721aa4
|
254 |
EXPORT_SYMBOL(_raw_read_unlock); |
892a7c67c
|
255 |
#endif |
1da177e4c
|
256 |
|
6beb00092
|
257 |
#ifndef CONFIG_INLINE_READ_UNLOCK_IRQRESTORE |
9c1721aa4
|
258 |
void __lockfunc _raw_read_unlock_irqrestore(rwlock_t *lock, unsigned long flags) |
1da177e4c
|
259 |
{ |
9c1721aa4
|
260 |
__raw_read_unlock_irqrestore(lock, flags); |
1da177e4c
|
261 |
} |
9c1721aa4
|
262 |
EXPORT_SYMBOL(_raw_read_unlock_irqrestore); |
892a7c67c
|
263 |
#endif |
1da177e4c
|
264 |
|
6beb00092
|
265 |
#ifndef CONFIG_INLINE_READ_UNLOCK_IRQ |
9c1721aa4
|
266 |
void __lockfunc _raw_read_unlock_irq(rwlock_t *lock) |
1da177e4c
|
267 |
{ |
9c1721aa4
|
268 |
__raw_read_unlock_irq(lock); |
1da177e4c
|
269 |
} |
9c1721aa4
|
270 |
EXPORT_SYMBOL(_raw_read_unlock_irq); |
892a7c67c
|
271 |
#endif |
1da177e4c
|
272 |
|
6beb00092
|
273 |
#ifndef CONFIG_INLINE_READ_UNLOCK_BH |
9c1721aa4
|
274 |
void __lockfunc _raw_read_unlock_bh(rwlock_t *lock) |
1da177e4c
|
275 |
{ |
9c1721aa4
|
276 |
__raw_read_unlock_bh(lock); |
1da177e4c
|
277 |
} |
9c1721aa4
|
278 |
EXPORT_SYMBOL(_raw_read_unlock_bh); |
892a7c67c
|
279 |
#endif |
1da177e4c
|
280 |
|
b7b40ade5
|
281 |
#ifndef CONFIG_INLINE_WRITE_TRYLOCK |
9c1721aa4
|
282 |
int __lockfunc _raw_write_trylock(rwlock_t *lock) |
b7b40ade5
|
283 |
{ |
9c1721aa4
|
284 |
return __raw_write_trylock(lock); |
b7b40ade5
|
285 |
} |
9c1721aa4
|
286 |
EXPORT_SYMBOL(_raw_write_trylock); |
b7b40ade5
|
287 288 289 |
#endif #ifndef CONFIG_INLINE_WRITE_LOCK |
9c1721aa4
|
290 |
void __lockfunc _raw_write_lock(rwlock_t *lock) |
b7b40ade5
|
291 |
{ |
9c1721aa4
|
292 |
__raw_write_lock(lock); |
b7b40ade5
|
293 |
} |
9c1721aa4
|
294 |
EXPORT_SYMBOL(_raw_write_lock); |
b7b40ade5
|
295 296 297 |
#endif #ifndef CONFIG_INLINE_WRITE_LOCK_IRQSAVE |
9c1721aa4
|
298 |
unsigned long __lockfunc _raw_write_lock_irqsave(rwlock_t *lock) |
b7b40ade5
|
299 |
{ |
9c1721aa4
|
300 |
return __raw_write_lock_irqsave(lock); |
b7b40ade5
|
301 |
} |
9c1721aa4
|
302 |
EXPORT_SYMBOL(_raw_write_lock_irqsave); |
b7b40ade5
|
303 304 305 |
#endif #ifndef CONFIG_INLINE_WRITE_LOCK_IRQ |
9c1721aa4
|
306 |
void __lockfunc _raw_write_lock_irq(rwlock_t *lock) |
b7b40ade5
|
307 |
{ |
9c1721aa4
|
308 |
__raw_write_lock_irq(lock); |
b7b40ade5
|
309 |
} |
9c1721aa4
|
310 |
EXPORT_SYMBOL(_raw_write_lock_irq); |
b7b40ade5
|
311 312 313 |
#endif #ifndef CONFIG_INLINE_WRITE_LOCK_BH |
9c1721aa4
|
314 |
void __lockfunc _raw_write_lock_bh(rwlock_t *lock) |
b7b40ade5
|
315 |
{ |
9c1721aa4
|
316 |
__raw_write_lock_bh(lock); |
b7b40ade5
|
317 |
} |
9c1721aa4
|
318 |
EXPORT_SYMBOL(_raw_write_lock_bh); |
b7b40ade5
|
319 320 321 |
#endif #ifndef CONFIG_INLINE_WRITE_UNLOCK |
9c1721aa4
|
322 |
void __lockfunc _raw_write_unlock(rwlock_t *lock) |
b7b40ade5
|
323 |
{ |
9c1721aa4
|
324 |
__raw_write_unlock(lock); |
b7b40ade5
|
325 |
} |
9c1721aa4
|
326 |
EXPORT_SYMBOL(_raw_write_unlock); |
b7b40ade5
|
327 |
#endif |
6beb00092
|
328 |
#ifndef CONFIG_INLINE_WRITE_UNLOCK_IRQRESTORE |
9c1721aa4
|
329 |
void __lockfunc _raw_write_unlock_irqrestore(rwlock_t *lock, unsigned long flags) |
1da177e4c
|
330 |
{ |
9c1721aa4
|
331 |
__raw_write_unlock_irqrestore(lock, flags); |
1da177e4c
|
332 |
} |
9c1721aa4
|
333 |
EXPORT_SYMBOL(_raw_write_unlock_irqrestore); |
892a7c67c
|
334 |
#endif |
1da177e4c
|
335 |
|
6beb00092
|
336 |
#ifndef CONFIG_INLINE_WRITE_UNLOCK_IRQ |
9c1721aa4
|
337 |
void __lockfunc _raw_write_unlock_irq(rwlock_t *lock) |
1da177e4c
|
338 |
{ |
9c1721aa4
|
339 |
__raw_write_unlock_irq(lock); |
1da177e4c
|
340 |
} |
9c1721aa4
|
341 |
EXPORT_SYMBOL(_raw_write_unlock_irq); |
892a7c67c
|
342 |
#endif |
1da177e4c
|
343 |
|
6beb00092
|
344 |
#ifndef CONFIG_INLINE_WRITE_UNLOCK_BH |
9c1721aa4
|
345 |
void __lockfunc _raw_write_unlock_bh(rwlock_t *lock) |
1da177e4c
|
346 |
{ |
9c1721aa4
|
347 |
__raw_write_unlock_bh(lock); |
1da177e4c
|
348 |
} |
9c1721aa4
|
349 |
EXPORT_SYMBOL(_raw_write_unlock_bh); |
892a7c67c
|
350 |
#endif |
1da177e4c
|
351 |
|
b7b40ade5
|
352 |
#ifdef CONFIG_DEBUG_LOCK_ALLOC |
9c1721aa4
|
353 |
void __lockfunc _raw_spin_lock_nested(raw_spinlock_t *lock, int subclass) |
1da177e4c
|
354 |
{ |
b7b40ade5
|
355 356 |
preempt_disable(); spin_acquire(&lock->dep_map, subclass, 0, _RET_IP_); |
9828ea9d7
|
357 |
LOCK_CONTENDED(lock, do_raw_spin_trylock, do_raw_spin_lock); |
1da177e4c
|
358 |
} |
9c1721aa4
|
359 |
EXPORT_SYMBOL(_raw_spin_lock_nested); |
b7b40ade5
|
360 |
|
9c1721aa4
|
361 |
unsigned long __lockfunc _raw_spin_lock_irqsave_nested(raw_spinlock_t *lock, |
b7b40ade5
|
362 363 364 365 366 367 368 |
int subclass) { unsigned long flags; local_irq_save(flags); preempt_disable(); spin_acquire(&lock->dep_map, subclass, 0, _RET_IP_); |
9828ea9d7
|
369 370 |
LOCK_CONTENDED_FLAGS(lock, do_raw_spin_trylock, do_raw_spin_lock, do_raw_spin_lock_flags, &flags); |
b7b40ade5
|
371 372 |
return flags; } |
9c1721aa4
|
373 |
EXPORT_SYMBOL(_raw_spin_lock_irqsave_nested); |
b7b40ade5
|
374 |
|
9c1721aa4
|
375 |
void __lockfunc _raw_spin_lock_nest_lock(raw_spinlock_t *lock, |
b7b40ade5
|
376 377 378 379 |
struct lockdep_map *nest_lock) { preempt_disable(); spin_acquire_nest(&lock->dep_map, 0, 0, nest_lock, _RET_IP_); |
9828ea9d7
|
380 |
LOCK_CONTENDED(lock, do_raw_spin_trylock, do_raw_spin_lock); |
b7b40ade5
|
381 |
} |
9c1721aa4
|
382 |
EXPORT_SYMBOL(_raw_spin_lock_nest_lock); |
b7b40ade5
|
383 |
|
892a7c67c
|
384 |
#endif |
1da177e4c
|
385 |
|
0764d23cf
|
386 |
notrace int in_lock_functions(unsigned long addr) |
1da177e4c
|
387 388 389 390 391 392 393 394 |
{ /* Linker adds these: start and end of __lockfunc functions */ extern char __lock_text_start[], __lock_text_end[]; return addr >= (unsigned long)__lock_text_start && addr < (unsigned long)__lock_text_end; } EXPORT_SYMBOL(in_lock_functions); |