1 // SPDX-License-Identifier: GPL-2.0
2 #include "mutex.h"
3
4 #include "debug.h"
5 #include <linux/string.h>
6 #include <errno.h>
7
check_err(const char * fn,int err)8 static void check_err(const char *fn, int err)
9 {
10 char sbuf[STRERR_BUFSIZE];
11
12 if (err == 0)
13 return;
14
15 pr_err("%s error: '%s'\n", fn, str_error_r(err, sbuf, sizeof(sbuf)));
16 }
17
18 #define CHECK_ERR(err) check_err(__func__, err)
19
__mutex_init(struct mutex * mtx,bool pshared,bool recursive)20 static void __mutex_init(struct mutex *mtx, bool pshared, bool recursive)
21 {
22 pthread_mutexattr_t attr;
23
24 CHECK_ERR(pthread_mutexattr_init(&attr));
25
26 #ifndef NDEBUG
27 /* In normal builds enable error checking, such as recursive usage. */
28 CHECK_ERR(pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_ERRORCHECK));
29 #endif
30 if (recursive)
31 CHECK_ERR(pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE));
32 if (pshared)
33 CHECK_ERR(pthread_mutexattr_setpshared(&attr, PTHREAD_PROCESS_SHARED));
34 CHECK_ERR(pthread_mutex_init(&mtx->lock, &attr));
35 CHECK_ERR(pthread_mutexattr_destroy(&attr));
36 }
37
mutex_init(struct mutex * mtx)38 void mutex_init(struct mutex *mtx)
39 {
40 __mutex_init(mtx, /*pshared=*/false, /*recursive=*/false);
41 }
42
mutex_init_pshared(struct mutex * mtx)43 void mutex_init_pshared(struct mutex *mtx)
44 {
45 __mutex_init(mtx, /*pshared=*/true, /*recursive=*/false);
46 }
47
mutex_init_recursive(struct mutex * mtx)48 void mutex_init_recursive(struct mutex *mtx)
49 {
50 __mutex_init(mtx, /*pshared=*/false, /*recursive=*/true);
51 }
52
mutex_destroy(struct mutex * mtx)53 void mutex_destroy(struct mutex *mtx)
54 {
55 CHECK_ERR(pthread_mutex_destroy(&mtx->lock));
56 }
57
mutex_lock(struct mutex * mtx)58 void mutex_lock(struct mutex *mtx)
59 NO_THREAD_SAFETY_ANALYSIS
60 {
61 CHECK_ERR(pthread_mutex_lock(&mtx->lock));
62 }
63
mutex_unlock(struct mutex * mtx)64 void mutex_unlock(struct mutex *mtx)
65 NO_THREAD_SAFETY_ANALYSIS
66 {
67 CHECK_ERR(pthread_mutex_unlock(&mtx->lock));
68 }
69
mutex_trylock(struct mutex * mtx)70 bool mutex_trylock(struct mutex *mtx)
71 {
72 int ret = pthread_mutex_trylock(&mtx->lock);
73
74 if (ret == 0)
75 return true; /* Lock acquired. */
76
77 if (ret == EBUSY)
78 return false; /* Lock busy. */
79
80 /* Print error. */
81 CHECK_ERR(ret);
82 return false;
83 }
84
__cond_init(struct cond * cnd,bool pshared)85 static void __cond_init(struct cond *cnd, bool pshared)
86 {
87 pthread_condattr_t attr;
88
89 CHECK_ERR(pthread_condattr_init(&attr));
90 if (pshared)
91 CHECK_ERR(pthread_condattr_setpshared(&attr, PTHREAD_PROCESS_SHARED));
92
93 CHECK_ERR(pthread_cond_init(&cnd->cond, &attr));
94 CHECK_ERR(pthread_condattr_destroy(&attr));
95 }
96
cond_init(struct cond * cnd)97 void cond_init(struct cond *cnd)
98 {
99 __cond_init(cnd, /*pshared=*/false);
100 }
101
cond_init_pshared(struct cond * cnd)102 void cond_init_pshared(struct cond *cnd)
103 {
104 __cond_init(cnd, /*pshared=*/true);
105 }
106
cond_destroy(struct cond * cnd)107 void cond_destroy(struct cond *cnd)
108 {
109 CHECK_ERR(pthread_cond_destroy(&cnd->cond));
110 }
111
cond_wait(struct cond * cnd,struct mutex * mtx)112 void cond_wait(struct cond *cnd, struct mutex *mtx)
113 {
114 CHECK_ERR(pthread_cond_wait(&cnd->cond, &mtx->lock));
115 }
116
cond_signal(struct cond * cnd)117 void cond_signal(struct cond *cnd)
118 {
119 CHECK_ERR(pthread_cond_signal(&cnd->cond));
120 }
121
cond_broadcast(struct cond * cnd)122 void cond_broadcast(struct cond *cnd)
123 {
124 CHECK_ERR(pthread_cond_broadcast(&cnd->cond));
125 }
126