| /* SPDX-License-Identifier: GPL-2.0 */ |
| /* |
| * Glibc independent futex library for testing kernel functionality. |
| * Shamelessly stolen from Darren Hart <dvhltc@us.ibm.com> |
| * http://git.kernel.org/cgit/linux/kernel/git/dvhart/futextest.git/ |
| */ |
| |
| #ifndef _FUTEX_H |
| #define _FUTEX_H |
| |
| #include <unistd.h> |
| #include <sys/syscall.h> |
| #include <sys/types.h> |
| #include <linux/futex.h> |
| |
| /** |
| * futex() - SYS_futex syscall wrapper |
| * @uaddr: address of first futex |
| * @op: futex op code |
| * @val: typically expected value of uaddr, but varies by op |
| * @timeout: typically an absolute struct timespec (except where noted |
| * otherwise). Overloaded by some ops |
| * @uaddr2: address of second futex for some ops\ |
| * @val3: varies by op |
| * @opflags: flags to be bitwise OR'd with op, such as FUTEX_PRIVATE_FLAG |
| * |
| * futex() is used by all the following futex op wrappers. It can also be |
| * used for misuse and abuse testing. Generally, the specific op wrappers |
| * should be used instead. It is a macro instead of an static inline function as |
| * some of the types over overloaded (timeout is used for nr_requeue for |
| * example). |
| * |
| * These argument descriptions are the defaults for all |
| * like-named arguments in the following wrappers except where noted below. |
| */ |
| #define futex(uaddr, op, val, timeout, uaddr2, val3, opflags) \ |
| syscall(SYS_futex, uaddr, op | opflags, val, timeout, uaddr2, val3) |
| |
| /** |
| * futex_wait() - block on uaddr with optional timeout |
| * @timeout: relative timeout |
| */ |
| static inline int |
| futex_wait(u_int32_t *uaddr, u_int32_t val, struct timespec *timeout, int opflags) |
| { |
| return futex(uaddr, FUTEX_WAIT, val, timeout, NULL, 0, opflags); |
| } |
| |
| /** |
| * futex_wake() - wake one or more tasks blocked on uaddr |
| * @nr_wake: wake up to this many tasks |
| */ |
| static inline int |
| futex_wake(u_int32_t *uaddr, int nr_wake, int opflags) |
| { |
| return futex(uaddr, FUTEX_WAKE, nr_wake, NULL, NULL, 0, opflags); |
| } |
| |
| /** |
| * futex_lock_pi() - block on uaddr as a PI mutex |
| */ |
| static inline int |
| futex_lock_pi(u_int32_t *uaddr, struct timespec *timeout, int opflags) |
| { |
| return futex(uaddr, FUTEX_LOCK_PI, 0, timeout, NULL, 0, opflags); |
| } |
| |
| /** |
| * futex_unlock_pi() - release uaddr as a PI mutex, waking the top waiter |
| */ |
| static inline int |
| futex_unlock_pi(u_int32_t *uaddr, int opflags) |
| { |
| return futex(uaddr, FUTEX_UNLOCK_PI, 0, NULL, NULL, 0, opflags); |
| } |
| |
| /** |
| * futex_cmp_requeue() - requeue tasks from uaddr to uaddr2 |
| * @nr_wake: wake up to this many tasks |
| * @nr_requeue: requeue up to this many tasks |
| */ |
| static inline int |
| futex_cmp_requeue(u_int32_t *uaddr, u_int32_t val, u_int32_t *uaddr2, int nr_wake, |
| int nr_requeue, int opflags) |
| { |
| return futex(uaddr, FUTEX_CMP_REQUEUE, nr_wake, nr_requeue, uaddr2, |
| val, opflags); |
| } |
| |
| #ifndef HAVE_PTHREAD_ATTR_SETAFFINITY_NP |
| #include <pthread.h> |
| #include <linux/compiler.h> |
| static inline int pthread_attr_setaffinity_np(pthread_attr_t *attr __maybe_unused, |
| size_t cpusetsize __maybe_unused, |
| cpu_set_t *cpuset __maybe_unused) |
| { |
| return 0; |
| } |
| #endif |
| |
| #endif /* _FUTEX_H */ |