~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/include/linux/spinlock.h

Version: ~ [ linux-5.9-rc6 ] ~ [ linux-5.8.10 ] ~ [ linux-5.7.19 ] ~ [ linux-5.6.19 ] ~ [ linux-5.5.19 ] ~ [ linux-5.4.66 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.146 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.198 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.236 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.236 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.140 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.85 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 #ifndef __LINUX_SPINLOCK_H
  2 #define __LINUX_SPINLOCK_H
  3 
  4 /*
  5  * include/linux/spinlock.h - generic spinlock/rwlock declarations
  6  *
  7  * here's the role of the various spinlock/rwlock related include files:
  8  *
  9  * on SMP builds:
 10  *
 11  *  asm/spinlock_types.h: contains the arch_spinlock_t/arch_rwlock_t and the
 12  *                        initializers
 13  *
 14  *  linux/spinlock_types.h:
 15  *                        defines the generic type and initializers
 16  *
 17  *  asm/spinlock.h:       contains the arch_spin_*()/etc. lowlevel
 18  *                        implementations, mostly inline assembly code
 19  *
 20  *   (also included on UP-debug builds:)
 21  *
 22  *  linux/spinlock_api_smp.h:
 23  *                        contains the prototypes for the _spin_*() APIs.
 24  *
 25  *  linux/spinlock.h:     builds the final spin_*() APIs.
 26  *
 27  * on UP builds:
 28  *
 29  *  linux/spinlock_type_up.h:
 30  *                        contains the generic, simplified UP spinlock type.
 31  *                        (which is an empty structure on non-debug builds)
 32  *
 33  *  linux/spinlock_types.h:
 34  *                        defines the generic type and initializers
 35  *
 36  *  linux/spinlock_up.h:
 37  *                        contains the arch_spin_*()/etc. version of UP
 38  *                        builds. (which are NOPs on non-debug, non-preempt
 39  *                        builds)
 40  *
 41  *   (included on UP-non-debug builds:)
 42  *
 43  *  linux/spinlock_api_up.h:
 44  *                        builds the _spin_*() APIs.
 45  *
 46  *  linux/spinlock.h:     builds the final spin_*() APIs.
 47  */
 48 
 49 #include <linux/typecheck.h>
 50 #include <linux/preempt.h>
 51 #include <linux/linkage.h>
 52 #include <linux/compiler.h>
 53 #include <linux/irqflags.h>
 54 #include <linux/thread_info.h>
 55 #include <linux/kernel.h>
 56 #include <linux/stringify.h>
 57 #include <linux/bottom_half.h>
 58 #include <asm/barrier.h>
 59 
 60 
 61 /*
 62  * Must define these before including other files, inline functions need them
 63  */
 64 #define LOCK_SECTION_NAME ".text..lock."KBUILD_BASENAME
 65 
 66 #define LOCK_SECTION_START(extra)               \
 67         ".subsection 1\n\t"                     \
 68         extra                                   \
 69         ".ifndef " LOCK_SECTION_NAME "\n\t"     \
 70         LOCK_SECTION_NAME ":\n\t"               \
 71         ".endif\n"
 72 
 73 #define LOCK_SECTION_END                        \
 74         ".previous\n\t"
 75 
 76 #define __lockfunc __attribute__((section(".spinlock.text")))
 77 
 78 /*
 79  * Pull the arch_spinlock_t and arch_rwlock_t definitions:
 80  */
 81 #include <linux/spinlock_types.h>
 82 
 83 /*
 84  * Pull the arch_spin*() functions/declarations (UP-nondebug doesn't need them):
 85  */
 86 #ifdef CONFIG_SMP
 87 # include <asm/spinlock.h>
 88 #else
 89 # include <linux/spinlock_up.h>
 90 #endif
 91 
 92 #ifdef CONFIG_DEBUG_SPINLOCK
 93   extern void __raw_spin_lock_init(raw_spinlock_t *lock, const char *name,
 94                                    struct lock_class_key *key);
 95 # define raw_spin_lock_init(lock)                               \
 96 do {                                                            \
 97         static struct lock_class_key __key;                     \
 98                                                                 \
 99         __raw_spin_lock_init((lock), #lock, &__key);            \
100 } while (0)
101 
102 #else
103 # define raw_spin_lock_init(lock)                               \
104         do { *(lock) = __RAW_SPIN_LOCK_UNLOCKED(lock); } while (0)
105 #endif
106 
107 #define raw_spin_is_locked(lock)        arch_spin_is_locked(&(lock)->raw_lock)
108 
109 #ifdef CONFIG_GENERIC_LOCKBREAK
110 #define raw_spin_is_contended(lock) ((lock)->break_lock)
111 #else
112 
113 #ifdef arch_spin_is_contended
114 #define raw_spin_is_contended(lock)     arch_spin_is_contended(&(lock)->raw_lock)
115 #else
116 #define raw_spin_is_contended(lock)     (((void)(lock), 0))
117 #endif /*arch_spin_is_contended*/
118 #endif
119 
120 /*
121  * Despite its name it doesn't necessarily has to be a full barrier.
122  * It should only guarantee that a STORE before the critical section
123  * can not be reordered with a LOAD inside this section.
124  * spin_lock() is the one-way barrier, this LOAD can not escape out
125  * of the region. So the default implementation simply ensures that
126  * a STORE can not move into the critical section, smp_wmb() should
127  * serialize it with another STORE done by spin_lock().
128  */
129 #ifndef smp_mb__before_spinlock
130 #define smp_mb__before_spinlock()       smp_wmb()
131 #endif
132 
133 /**
134  * raw_spin_unlock_wait - wait until the spinlock gets unlocked
135  * @lock: the spinlock in question.
136  */
137 #define raw_spin_unlock_wait(lock)      arch_spin_unlock_wait(&(lock)->raw_lock)
138 
139 #ifdef CONFIG_DEBUG_SPINLOCK
140  extern void do_raw_spin_lock(raw_spinlock_t *lock) __acquires(lock);
141 #define do_raw_spin_lock_flags(lock, flags) do_raw_spin_lock(lock)
142  extern int do_raw_spin_trylock(raw_spinlock_t *lock);
143  extern void do_raw_spin_unlock(raw_spinlock_t *lock) __releases(lock);
144 #else
145 static inline void do_raw_spin_lock(raw_spinlock_t *lock) __acquires(lock)
146 {
147         __acquire(lock);
148         arch_spin_lock(&lock->raw_lock);
149 }
150 
151 static inline void
152 do_raw_spin_lock_flags(raw_spinlock_t *lock, unsigned long *flags) __acquires(lock)
153 {
154         __acquire(lock);
155         arch_spin_lock_flags(&lock->raw_lock, *flags);
156 }
157 
158 static inline int do_raw_spin_trylock(raw_spinlock_t *lock)
159 {
160         return arch_spin_trylock(&(lock)->raw_lock);
161 }
162 
163 static inline void do_raw_spin_unlock(raw_spinlock_t *lock) __releases(lock)
164 {
165         arch_spin_unlock(&lock->raw_lock);
166         __release(lock);
167 }
168 #endif
169 
170 /*
171  * Define the various spin_lock methods.  Note we define these
172  * regardless of whether CONFIG_SMP or CONFIG_PREEMPT are set. The
173  * various methods are defined as nops in the case they are not
174  * required.
175  */
176 #define raw_spin_trylock(lock)  __cond_lock(lock, _raw_spin_trylock(lock))
177 
178 #define raw_spin_lock(lock)     _raw_spin_lock(lock)
179 
180 #ifdef CONFIG_DEBUG_LOCK_ALLOC
181 # define raw_spin_lock_nested(lock, subclass) \
182         _raw_spin_lock_nested(lock, subclass)
183 
184 # define raw_spin_lock_nest_lock(lock, nest_lock)                       \
185          do {                                                           \
186                  typecheck(struct lockdep_map *, &(nest_lock)->dep_map);\
187                  _raw_spin_lock_nest_lock(lock, &(nest_lock)->dep_map); \
188          } while (0)
189 #else
190 # define raw_spin_lock_nested(lock, subclass)           _raw_spin_lock(lock)
191 # define raw_spin_lock_nest_lock(lock, nest_lock)       _raw_spin_lock(lock)
192 #endif
193 
194 #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
195 
196 #define raw_spin_lock_irqsave(lock, flags)                      \
197         do {                                            \
198                 typecheck(unsigned long, flags);        \
199                 flags = _raw_spin_lock_irqsave(lock);   \
200         } while (0)
201 
202 #ifdef CONFIG_DEBUG_LOCK_ALLOC
203 #define raw_spin_lock_irqsave_nested(lock, flags, subclass)             \
204         do {                                                            \
205                 typecheck(unsigned long, flags);                        \
206                 flags = _raw_spin_lock_irqsave_nested(lock, subclass);  \
207         } while (0)
208 #else
209 #define raw_spin_lock_irqsave_nested(lock, flags, subclass)             \
210         do {                                                            \
211                 typecheck(unsigned long, flags);                        \
212                 flags = _raw_spin_lock_irqsave(lock);                   \
213         } while (0)
214 #endif
215 
216 #else
217 
218 #define raw_spin_lock_irqsave(lock, flags)              \
219         do {                                            \
220                 typecheck(unsigned long, flags);        \
221                 _raw_spin_lock_irqsave(lock, flags);    \
222         } while (0)
223 
224 #define raw_spin_lock_irqsave_nested(lock, flags, subclass)     \
225         raw_spin_lock_irqsave(lock, flags)
226 
227 #endif
228 
229 #define raw_spin_lock_irq(lock)         _raw_spin_lock_irq(lock)
230 #define raw_spin_lock_bh(lock)          _raw_spin_lock_bh(lock)
231 #define raw_spin_unlock(lock)           _raw_spin_unlock(lock)
232 #define raw_spin_unlock_irq(lock)       _raw_spin_unlock_irq(lock)
233 
234 #define raw_spin_unlock_irqrestore(lock, flags)         \
235         do {                                                    \
236                 typecheck(unsigned long, flags);                \
237                 _raw_spin_unlock_irqrestore(lock, flags);       \
238         } while (0)
239 #define raw_spin_unlock_bh(lock)        _raw_spin_unlock_bh(lock)
240 
241 #define raw_spin_trylock_bh(lock) \
242         __cond_lock(lock, _raw_spin_trylock_bh(lock))
243 
244 #define raw_spin_trylock_irq(lock) \
245 ({ \
246         local_irq_disable(); \
247         raw_spin_trylock(lock) ? \
248         1 : ({ local_irq_enable(); 0;  }); \
249 })
250 
251 #define raw_spin_trylock_irqsave(lock, flags) \
252 ({ \
253         local_irq_save(flags); \
254         raw_spin_trylock(lock) ? \
255         1 : ({ local_irq_restore(flags); 0; }); \
256 })
257 
258 /**
259  * raw_spin_can_lock - would raw_spin_trylock() succeed?
260  * @lock: the spinlock in question.
261  */
262 #define raw_spin_can_lock(lock) (!raw_spin_is_locked(lock))
263 
264 /* Include rwlock functions */
265 #include <linux/rwlock.h>
266 
267 /*
268  * Pull the _spin_*()/_read_*()/_write_*() functions/declarations:
269  */
270 #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
271 # include <linux/spinlock_api_smp.h>
272 #else
273 # include <linux/spinlock_api_up.h>
274 #endif
275 
276 /*
277  * Map the spin_lock functions to the raw variants for PREEMPT_RT=n
278  */
279 
280 static inline raw_spinlock_t *spinlock_check(spinlock_t *lock)
281 {
282         return &lock->rlock;
283 }
284 
285 #define spin_lock_init(_lock)                           \
286 do {                                                    \
287         spinlock_check(_lock);                          \
288         raw_spin_lock_init(&(_lock)->rlock);            \
289 } while (0)
290 
291 static inline void spin_lock(spinlock_t *lock)
292 {
293         raw_spin_lock(&lock->rlock);
294 }
295 
296 static inline void spin_lock_bh(spinlock_t *lock)
297 {
298         raw_spin_lock_bh(&lock->rlock);
299 }
300 
301 static inline int spin_trylock(spinlock_t *lock)
302 {
303         return raw_spin_trylock(&lock->rlock);
304 }
305 
306 #define spin_lock_nested(lock, subclass)                        \
307 do {                                                            \
308         raw_spin_lock_nested(spinlock_check(lock), subclass);   \
309 } while (0)
310 
311 #define spin_lock_nest_lock(lock, nest_lock)                            \
312 do {                                                                    \
313         raw_spin_lock_nest_lock(spinlock_check(lock), nest_lock);       \
314 } while (0)
315 
316 static inline void spin_lock_irq(spinlock_t *lock)
317 {
318         raw_spin_lock_irq(&lock->rlock);
319 }
320 
321 #define spin_lock_irqsave(lock, flags)                          \
322 do {                                                            \
323         raw_spin_lock_irqsave(spinlock_check(lock), flags);     \
324 } while (0)
325 
326 #define spin_lock_irqsave_nested(lock, flags, subclass)                 \
327 do {                                                                    \
328         raw_spin_lock_irqsave_nested(spinlock_check(lock), flags, subclass); \
329 } while (0)
330 
331 static inline void spin_unlock(spinlock_t *lock)
332 {
333         raw_spin_unlock(&lock->rlock);
334 }
335 
336 static inline void spin_unlock_bh(spinlock_t *lock)
337 {
338         raw_spin_unlock_bh(&lock->rlock);
339 }
340 
341 static inline void spin_unlock_irq(spinlock_t *lock)
342 {
343         raw_spin_unlock_irq(&lock->rlock);
344 }
345 
346 static inline void spin_unlock_irqrestore(spinlock_t *lock, unsigned long flags)
347 {
348         raw_spin_unlock_irqrestore(&lock->rlock, flags);
349 }
350 
351 static inline int spin_trylock_bh(spinlock_t *lock)
352 {
353         return raw_spin_trylock_bh(&lock->rlock);
354 }
355 
356 static inline int spin_trylock_irq(spinlock_t *lock)
357 {
358         return raw_spin_trylock_irq(&lock->rlock);
359 }
360 
361 #define spin_trylock_irqsave(lock, flags)                       \
362 ({                                                              \
363         raw_spin_trylock_irqsave(spinlock_check(lock), flags); \
364 })
365 
366 static inline void spin_unlock_wait(spinlock_t *lock)
367 {
368         raw_spin_unlock_wait(&lock->rlock);
369 }
370 
371 static inline int spin_is_locked(spinlock_t *lock)
372 {
373         return raw_spin_is_locked(&lock->rlock);
374 }
375 
376 static inline int spin_is_contended(spinlock_t *lock)
377 {
378         return raw_spin_is_contended(&lock->rlock);
379 }
380 
381 static inline int spin_can_lock(spinlock_t *lock)
382 {
383         return raw_spin_can_lock(&lock->rlock);
384 }
385 
386 #define assert_spin_locked(lock)        assert_raw_spin_locked(&(lock)->rlock)
387 
388 /*
389  * Pull the atomic_t declaration:
390  * (asm-mips/atomic.h needs above definitions)
391  */
392 #include <linux/atomic.h>
393 /**
394  * atomic_dec_and_lock - lock on reaching reference count zero
395  * @atomic: the atomic counter
396  * @lock: the spinlock in question
397  *
398  * Decrements @atomic by 1.  If the result is 0, returns true and locks
399  * @lock.  Returns false for all other cases.
400  */
401 extern int _atomic_dec_and_lock(atomic_t *atomic, spinlock_t *lock);
402 #define atomic_dec_and_lock(atomic, lock) \
403                 __cond_lock(lock, _atomic_dec_and_lock(atomic, lock))
404 
405 #endif /* __LINUX_SPINLOCK_H */
406 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp