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Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1/*
2 * Glibc independent futex library for testing kernel functionality.
3 * Shamelessly stolen from Darren Hart <dvhltc@us.ibm.com>
4 * http://git.kernel.org/cgit/linux/kernel/git/dvhart/futextest.git/
5 */
6
7#ifndef _FUTEX_H
8#define _FUTEX_H
9
10#include <unistd.h>
11#include <sys/syscall.h>
12#include <sys/types.h>
13#include <linux/futex.h>
14
15/**
16 * futex() - SYS_futex syscall wrapper
17 * @uaddr: address of first futex
18 * @op: futex op code
19 * @val: typically expected value of uaddr, but varies by op
20 * @timeout: typically an absolute struct timespec (except where noted
21 * otherwise). Overloaded by some ops
22 * @uaddr2: address of second futex for some ops\
23 * @val3: varies by op
24 * @opflags: flags to be bitwise OR'd with op, such as FUTEX_PRIVATE_FLAG
25 *
26 * futex() is used by all the following futex op wrappers. It can also be
27 * used for misuse and abuse testing. Generally, the specific op wrappers
28 * should be used instead. It is a macro instead of an static inline function as
29 * some of the types over overloaded (timeout is used for nr_requeue for
30 * example).
31 *
32 * These argument descriptions are the defaults for all
33 * like-named arguments in the following wrappers except where noted below.
34 */
35#define futex(uaddr, op, val, timeout, uaddr2, val3, opflags) \
36 syscall(SYS_futex, uaddr, op | opflags, val, timeout, uaddr2, val3)
37
38/**
39 * futex_wait() - block on uaddr with optional timeout
40 * @timeout: relative timeout
41 */
42static inline int
43futex_wait(u_int32_t *uaddr, u_int32_t val, struct timespec *timeout, int opflags)
44{
45 return futex(uaddr, FUTEX_WAIT, val, timeout, NULL, 0, opflags);
46}
47
48/**
49 * futex_wake() - wake one or more tasks blocked on uaddr
50 * @nr_wake: wake up to this many tasks
51 */
52static inline int
53futex_wake(u_int32_t *uaddr, int nr_wake, int opflags)
54{
55 return futex(uaddr, FUTEX_WAKE, nr_wake, NULL, NULL, 0, opflags);
56}
57
58/**
59 * futex_lock_pi() - block on uaddr as a PI mutex
60 * @detect: whether (1) or not (0) to perform deadlock detection
61 */
62static inline int
63futex_lock_pi(u_int32_t *uaddr, struct timespec *timeout, int detect,
64 int opflags)
65{
66 return futex(uaddr, FUTEX_LOCK_PI, detect, timeout, NULL, 0, opflags);
67}
68
69/**
70 * futex_unlock_pi() - release uaddr as a PI mutex, waking the top waiter
71 */
72static inline int
73futex_unlock_pi(u_int32_t *uaddr, int opflags)
74{
75 return futex(uaddr, FUTEX_UNLOCK_PI, 0, NULL, NULL, 0, opflags);
76}
77
78/**
79* futex_cmp_requeue() - requeue tasks from uaddr to uaddr2
80* @nr_wake: wake up to this many tasks
81* @nr_requeue: requeue up to this many tasks
82*/
83static inline int
84futex_cmp_requeue(u_int32_t *uaddr, u_int32_t val, u_int32_t *uaddr2, int nr_wake,
85 int nr_requeue, int opflags)
86{
87 return futex(uaddr, FUTEX_CMP_REQUEUE, nr_wake, nr_requeue, uaddr2,
88 val, opflags);
89}
90
91#ifndef HAVE_PTHREAD_ATTR_SETAFFINITY_NP
92#include <pthread.h>
93static inline int pthread_attr_setaffinity_np(pthread_attr_t *attr,
94 size_t cpusetsize,
95 cpu_set_t *cpuset)
96{
97 attr = attr;
98 cpusetsize = cpusetsize;
99 cpuset = cpuset;
100 return 0;
101}
102#endif
103
104#endif /* _FUTEX_H */