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1/* SPDX-License-Identifier: GPL-2.0 */2/*3 * Glibc independent futex library for testing kernel functionality.4 * Shamelessly stolen from Darren Hart <dvhltc@us.ibm.com>5 * http://git.kernel.org/cgit/linux/kernel/git/dvhart/futextest.git/6 */7 8#ifndef _FUTEX_H9#define _FUTEX_H10 11#include <unistd.h>12#include <sys/syscall.h>13#include <sys/types.h>14#include <linux/futex.h>15 16struct bench_futex_parameters {17 bool silent;18 bool fshared;19 bool mlockall;20 bool multi; /* lock-pi */21 bool pi; /* requeue-pi */22 bool broadcast; /* requeue */23 unsigned int runtime; /* seconds*/24 unsigned int nthreads;25 unsigned int nfutexes;26 unsigned int nwakes;27 unsigned int nrequeue;28};29 30/**31 * futex_syscall() - SYS_futex syscall wrapper32 * @uaddr: address of first futex33 * @op: futex op code34 * @val: typically expected value of uaddr, but varies by op35 * @timeout: typically an absolute struct timespec (except where noted36 * otherwise). Overloaded by some ops37 * @uaddr2: address of second futex for some ops38 * @val3: varies by op39 * @opflags: flags to be bitwise OR'd with op, such as FUTEX_PRIVATE_FLAG40 *41 * futex_syscall() is used by all the following futex op wrappers. It can also be42 * used for misuse and abuse testing. Generally, the specific op wrappers43 * should be used instead.44 *45 * These argument descriptions are the defaults for all46 * like-named arguments in the following wrappers except where noted below.47 */48static inline int49futex_syscall(volatile u_int32_t *uaddr, int op, u_int32_t val, struct timespec *timeout,50 volatile u_int32_t *uaddr2, int val3, int opflags)51{52 return syscall(SYS_futex, uaddr, op | opflags, val, timeout, uaddr2, val3);53}54 55static inline int56futex_syscall_nr_requeue(volatile u_int32_t *uaddr, int op, u_int32_t val, int nr_requeue,57 volatile u_int32_t *uaddr2, int val3, int opflags)58{59 return syscall(SYS_futex, uaddr, op | opflags, val, nr_requeue, uaddr2, val3);60}61 62/**63 * futex_wait() - block on uaddr with optional timeout64 * @timeout: relative timeout65 */66static inline int67futex_wait(u_int32_t *uaddr, u_int32_t val, struct timespec *timeout, int opflags)68{69 return futex_syscall(uaddr, FUTEX_WAIT, val, timeout, NULL, 0, opflags);70}71 72/**73 * futex_wake() - wake one or more tasks blocked on uaddr74 * @nr_wake: wake up to this many tasks75 */76static inline int77futex_wake(u_int32_t *uaddr, int nr_wake, int opflags)78{79 return futex_syscall(uaddr, FUTEX_WAKE, nr_wake, NULL, NULL, 0, opflags);80}81 82/**83 * futex_lock_pi() - block on uaddr as a PI mutex84 */85static inline int86futex_lock_pi(u_int32_t *uaddr, struct timespec *timeout, int opflags)87{88 return futex_syscall(uaddr, FUTEX_LOCK_PI, 0, timeout, NULL, 0, opflags);89}90 91/**92 * futex_unlock_pi() - release uaddr as a PI mutex, waking the top waiter93 */94static inline int95futex_unlock_pi(u_int32_t *uaddr, int opflags)96{97 return futex_syscall(uaddr, FUTEX_UNLOCK_PI, 0, NULL, NULL, 0, opflags);98}99 100/**101* futex_cmp_requeue() - requeue tasks from uaddr to uaddr2102* @nr_wake: wake up to this many tasks103* @nr_requeue: requeue up to this many tasks104*/105static inline int106futex_cmp_requeue(u_int32_t *uaddr, u_int32_t val, u_int32_t *uaddr2, int nr_wake,107 int nr_requeue, int opflags)108{109 return futex_syscall_nr_requeue(uaddr, FUTEX_CMP_REQUEUE, nr_wake, nr_requeue, uaddr2,110 val, opflags);111}112 113/**114 * futex_wait_requeue_pi() - block on uaddr and prepare to requeue to uaddr2115 * @uaddr: non-PI futex source116 * @uaddr2: PI futex target117 *118 * This is the first half of the requeue_pi mechanism. It shall always be119 * paired with futex_cmp_requeue_pi().120 */121static inline int122futex_wait_requeue_pi(u_int32_t *uaddr, u_int32_t val, u_int32_t *uaddr2,123 struct timespec *timeout, int opflags)124{125 return futex_syscall(uaddr, FUTEX_WAIT_REQUEUE_PI, val, timeout, uaddr2, 0,126 opflags);127}128 129/**130 * futex_cmp_requeue_pi() - requeue tasks from uaddr to uaddr2131 * @uaddr: non-PI futex source132 * @uaddr2: PI futex target133 * @nr_requeue: requeue up to this many tasks134 *135 * This is the second half of the requeue_pi mechanism. It shall always be136 * paired with futex_wait_requeue_pi(). The first waker is always awoken.137 */138static inline int139futex_cmp_requeue_pi(u_int32_t *uaddr, u_int32_t val, u_int32_t *uaddr2,140 int nr_requeue, int opflags)141{142 return futex_syscall_nr_requeue(uaddr, FUTEX_CMP_REQUEUE_PI, 1, nr_requeue, uaddr2,143 val, opflags);144}145 146#endif /* _FUTEX_H */147