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
8static 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
20static void __mutex_init(struct mutex *mtx, bool pshared)
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 (pshared)
31 CHECK_ERR(pthread_mutexattr_setpshared(&attr, PTHREAD_PROCESS_SHARED));
32
33 CHECK_ERR(pthread_mutex_init(&mtx->lock, &attr));
34 CHECK_ERR(pthread_mutexattr_destroy(&attr));
35}
36
37void mutex_init(struct mutex *mtx)
38{
39 __mutex_init(mtx, /*pshared=*/false);
40}
41
42void mutex_init_pshared(struct mutex *mtx)
43{
44 __mutex_init(mtx, /*pshared=*/true);
45}
46
47void mutex_destroy(struct mutex *mtx)
48{
49 CHECK_ERR(pthread_mutex_destroy(&mtx->lock));
50}
51
52void mutex_lock(struct mutex *mtx)
53 NO_THREAD_SAFETY_ANALYSIS
54{
55 CHECK_ERR(pthread_mutex_lock(&mtx->lock));
56}
57
58void mutex_unlock(struct mutex *mtx)
59 NO_THREAD_SAFETY_ANALYSIS
60{
61 CHECK_ERR(pthread_mutex_unlock(&mtx->lock));
62}
63
64bool mutex_trylock(struct mutex *mtx)
65{
66 int ret = pthread_mutex_trylock(&mtx->lock);
67
68 if (ret == 0)
69 return true; /* Lock acquired. */
70
71 if (ret == EBUSY)
72 return false; /* Lock busy. */
73
74 /* Print error. */
75 CHECK_ERR(ret);
76 return false;
77}
78
79static void __cond_init(struct cond *cnd, bool pshared)
80{
81 pthread_condattr_t attr;
82
83 CHECK_ERR(pthread_condattr_init(&attr));
84 if (pshared)
85 CHECK_ERR(pthread_condattr_setpshared(&attr, PTHREAD_PROCESS_SHARED));
86
87 CHECK_ERR(pthread_cond_init(&cnd->cond, &attr));
88 CHECK_ERR(pthread_condattr_destroy(&attr));
89}
90
91void cond_init(struct cond *cnd)
92{
93 __cond_init(cnd, /*pshared=*/false);
94}
95
96void cond_init_pshared(struct cond *cnd)
97{
98 __cond_init(cnd, /*pshared=*/true);
99}
100
101void cond_destroy(struct cond *cnd)
102{
103 CHECK_ERR(pthread_cond_destroy(&cnd->cond));
104}
105
106void cond_wait(struct cond *cnd, struct mutex *mtx)
107{
108 CHECK_ERR(pthread_cond_wait(&cnd->cond, &mtx->lock));
109}
110
111void cond_signal(struct cond *cnd)
112{
113 CHECK_ERR(pthread_cond_signal(&cnd->cond));
114}
115
116void cond_broadcast(struct cond *cnd)
117{
118 CHECK_ERR(pthread_cond_broadcast(&cnd->cond));
119}
120

source code of linux/tools/perf/util/mutex.c