source: mainline/kernel/generic/include/synch/spinlock.h@ 69511176

serial ticket/834-toolchain-update topic/msim-upgrade topic/simplify-dev-export
Last change on this file since 69511176 was 8df5f20, checked in by Jiří Zárevúcky <zarevucky.jiri@…>, 6 years ago

Rename NO_TRACE to _NO_TRACE

<trace.h> may end up transitively included from standard headers,
so it needs to be a reserved identifier.
  • Property mode set to 100644
File size: 8.1 KB
Line 
1/*
2 * Copyright (c) 2001-2004 Jakub Jermar
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * - Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * - Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * - The name of the author may not be used to endorse or promote products
15 * derived from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29/** @addtogroup kernel_sync
30 * @{
31 */
32/** @file
33 */
34
35#ifndef KERN_SPINLOCK_H_
36#define KERN_SPINLOCK_H_
37
38#include <assert.h>
39#include <stdatomic.h>
40#include <stdbool.h>
41#include <preemption.h>
42#include <arch/asm.h>
43
44#ifdef CONFIG_SMP
45
46typedef struct spinlock {
47 atomic_flag flag;
48
49#ifdef CONFIG_DEBUG_SPINLOCK
50 const char *name;
51#endif /* CONFIG_DEBUG_SPINLOCK */
52} spinlock_t;
53
54/*
55 * SPINLOCK_DECLARE is to be used for dynamically allocated spinlocks,
56 * where the lock gets initialized in run time.
57 */
58#define SPINLOCK_DECLARE(lock_name) spinlock_t lock_name
59#define SPINLOCK_EXTERN(lock_name) extern spinlock_t lock_name
60
61/*
62 * SPINLOCK_INITIALIZE and SPINLOCK_STATIC_INITIALIZE are to be used
63 * for statically allocated spinlocks. They declare (either as global
64 * or static) symbol and initialize the lock.
65 */
66#ifdef CONFIG_DEBUG_SPINLOCK
67
68#define SPINLOCK_INITIALIZE_NAME(lock_name, desc_name) \
69 spinlock_t lock_name = { \
70 .name = desc_name, \
71 .flag = ATOMIC_FLAG_INIT \
72 }
73
74#define SPINLOCK_STATIC_INITIALIZE_NAME(lock_name, desc_name) \
75 static spinlock_t lock_name = { \
76 .name = desc_name, \
77 .flag = ATOMIC_FLAG_INIT \
78 }
79
80#define ASSERT_SPINLOCK(expr, lock) \
81 assert_verbose(expr, (lock)->name)
82
83#define spinlock_lock(lock) spinlock_lock_debug((lock))
84#define spinlock_unlock(lock) spinlock_unlock_debug((lock))
85
86#else /* CONFIG_DEBUG_SPINLOCK */
87
88#define SPINLOCK_INITIALIZE_NAME(lock_name, desc_name) \
89 spinlock_t lock_name = { \
90 .flag = ATOMIC_FLAG_INIT \
91 }
92
93#define SPINLOCK_STATIC_INITIALIZE_NAME(lock_name, desc_name) \
94 static spinlock_t lock_name = { \
95 .flag = ATOMIC_FLAG_INIT \
96 }
97
98#define ASSERT_SPINLOCK(expr, lock) \
99 assert(expr)
100
101/** Acquire spinlock
102 *
103 * @param lock Pointer to spinlock_t structure.
104 */
105_NO_TRACE static inline void spinlock_lock(spinlock_t *lock)
106{
107 preemption_disable();
108 while (atomic_flag_test_and_set_explicit(&lock->flag,
109 memory_order_acquire))
110 ;
111}
112
113/** Release spinlock
114 *
115 * @param lock Pointer to spinlock_t structure.
116 */
117_NO_TRACE static inline void spinlock_unlock(spinlock_t *lock)
118{
119 atomic_flag_clear_explicit(&lock->flag, memory_order_release);
120 preemption_enable();
121}
122
123#endif /* CONFIG_DEBUG_SPINLOCK */
124
125#define SPINLOCK_INITIALIZE(lock_name) \
126 SPINLOCK_INITIALIZE_NAME(lock_name, #lock_name)
127
128#define SPINLOCK_STATIC_INITIALIZE(lock_name) \
129 SPINLOCK_STATIC_INITIALIZE_NAME(lock_name, #lock_name)
130
131extern void spinlock_initialize(spinlock_t *, const char *);
132extern bool spinlock_trylock(spinlock_t *);
133extern void spinlock_lock_debug(spinlock_t *);
134extern void spinlock_unlock_debug(spinlock_t *);
135extern bool spinlock_locked(spinlock_t *);
136
137#ifdef CONFIG_DEBUG_SPINLOCK
138
139#include <log.h>
140
141#define DEADLOCK_THRESHOLD 100000000
142
143#define DEADLOCK_PROBE_INIT(pname) size_t pname = 0
144
145#define DEADLOCK_PROBE(pname, value) \
146 if ((pname)++ > (value)) { \
147 (pname) = 0; \
148 log(LF_OTHER, LVL_WARN, \
149 "Deadlock probe %s: exceeded threshold %u\n" \
150 "cpu%u: function=%s, line=%u\n", \
151 #pname, (value), CPU->id, __func__, __LINE__); \
152 }
153
154#else /* CONFIG_DEBUG_SPINLOCK */
155
156#define DEADLOCK_PROBE_INIT(pname)
157#define DEADLOCK_PROBE(pname, value)
158
159#endif /* CONFIG_DEBUG_SPINLOCK */
160
161#else /* CONFIG_SMP */
162
163/* On UP systems, spinlocks are effectively left out. */
164
165/* Allow the use of spinlock_t as an incomplete type. */
166typedef struct spinlock spinlock_t;
167
168#define SPINLOCK_DECLARE(name)
169#define SPINLOCK_EXTERN(name)
170
171#define SPINLOCK_INITIALIZE(name)
172#define SPINLOCK_STATIC_INITIALIZE(name)
173
174#define SPINLOCK_INITIALIZE_NAME(name, desc_name)
175#define SPINLOCK_STATIC_INITIALIZE_NAME(name, desc_name)
176
177#define ASSERT_SPINLOCK(expr, lock) assert(expr)
178
179#define spinlock_initialize(lock, name)
180
181#define spinlock_lock(lock) preemption_disable()
182#define spinlock_trylock(lock) ({ preemption_disable(); 1; })
183#define spinlock_unlock(lock) preemption_enable()
184#define spinlock_locked(lock) 1
185#define spinlock_unlocked(lock) 1
186
187#define DEADLOCK_PROBE_INIT(pname)
188#define DEADLOCK_PROBE(pname, value)
189
190#endif /* CONFIG_SMP */
191
192typedef struct {
193 SPINLOCK_DECLARE(lock); /**< Spinlock */
194 bool guard; /**< Flag whether ipl is valid */
195 ipl_t ipl; /**< Original interrupt level */
196} irq_spinlock_t;
197
198#define IRQ_SPINLOCK_DECLARE(lock_name) irq_spinlock_t lock_name
199#define IRQ_SPINLOCK_EXTERN(lock_name) extern irq_spinlock_t lock_name
200
201#ifdef CONFIG_SMP
202
203#define ASSERT_IRQ_SPINLOCK(expr, irq_lock) \
204 ASSERT_SPINLOCK(expr, &((irq_lock)->lock))
205
206/*
207 * IRQ_SPINLOCK_INITIALIZE and IRQ_SPINLOCK_STATIC_INITIALIZE are to be used
208 * for statically allocated interrupts-disabled spinlocks. They declare (either
209 * as global or static symbol) and initialize the lock.
210 */
211#ifdef CONFIG_DEBUG_SPINLOCK
212
213#define IRQ_SPINLOCK_INITIALIZE_NAME(lock_name, desc_name) \
214 irq_spinlock_t lock_name = { \
215 .lock = { \
216 .name = desc_name, \
217 .flag = ATOMIC_FLAG_INIT \
218 }, \
219 .guard = false, \
220 .ipl = 0 \
221 }
222
223#define IRQ_SPINLOCK_STATIC_INITIALIZE_NAME(lock_name, desc_name) \
224 static irq_spinlock_t lock_name = { \
225 .lock = { \
226 .name = desc_name, \
227 .flag = ATOMIC_FLAG_INIT \
228 }, \
229 .guard = false, \
230 .ipl = 0 \
231 }
232
233#else /* CONFIG_DEBUG_SPINLOCK */
234
235#define IRQ_SPINLOCK_INITIALIZE_NAME(lock_name, desc_name) \
236 irq_spinlock_t lock_name = { \
237 .lock = { \
238 .flag = ATOMIC_FLAG_INIT \
239 }, \
240 .guard = false, \
241 .ipl = 0 \
242 }
243
244#define IRQ_SPINLOCK_STATIC_INITIALIZE_NAME(lock_name, desc_name) \
245 static irq_spinlock_t lock_name = { \
246 .lock = { \
247 .flag = ATOMIC_FLAG_INIT \
248 }, \
249 .guard = false, \
250 .ipl = 0 \
251 }
252
253#endif /* CONFIG_DEBUG_SPINLOCK */
254
255#else /* CONFIG_SMP */
256
257/*
258 * Since the spinlocks are void on UP systems, we also need
259 * to have a special variant of interrupts-disabled spinlock
260 * macros which take this into account.
261 */
262
263#define ASSERT_IRQ_SPINLOCK(expr, irq_lock) \
264 ASSERT_SPINLOCK(expr, NULL)
265
266#define IRQ_SPINLOCK_INITIALIZE_NAME(lock_name, desc_name) \
267 irq_spinlock_t lock_name = { \
268 .guard = false, \
269 .ipl = 0 \
270 }
271
272#define IRQ_SPINLOCK_STATIC_INITIALIZE_NAME(lock_name, desc_name) \
273 static irq_spinlock_t lock_name = { \
274 .guard = false, \
275 .ipl = 0 \
276 }
277
278#endif /* CONFIG_SMP */
279
280#define IRQ_SPINLOCK_INITIALIZE(lock_name) \
281 IRQ_SPINLOCK_INITIALIZE_NAME(lock_name, #lock_name)
282
283#define IRQ_SPINLOCK_STATIC_INITIALIZE(lock_name) \
284 IRQ_SPINLOCK_STATIC_INITIALIZE_NAME(lock_name, #lock_name)
285
286extern void irq_spinlock_initialize(irq_spinlock_t *, const char *);
287extern void irq_spinlock_lock(irq_spinlock_t *, bool);
288extern void irq_spinlock_unlock(irq_spinlock_t *, bool);
289extern bool irq_spinlock_trylock(irq_spinlock_t *);
290extern void irq_spinlock_pass(irq_spinlock_t *, irq_spinlock_t *);
291extern void irq_spinlock_exchange(irq_spinlock_t *, irq_spinlock_t *);
292extern bool irq_spinlock_locked(irq_spinlock_t *);
293
294#endif
295
296/** @}
297 */
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