qemu-e2k/include/qemu/futex.h

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/*
* Wrappers around Linux futex syscall
*
* Copyright Red Hat, Inc. 2017
*
* Author:
* Paolo Bonzini <pbonzini@redhat.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*
*/
#ifndef QEMU_FUTEX_H
#define QEMU_FUTEX_H
#include <sys/syscall.h>
#include <linux/futex.h>
#define qemu_futex(...) syscall(__NR_futex, __VA_ARGS__)
static inline void qemu_futex_wake(void *f, int n)
{
qemu_futex(f, FUTEX_WAKE, n, NULL, NULL, 0);
}
static inline void qemu_futex_wait(void *f, unsigned val)
{
while (qemu_futex(f, FUTEX_WAIT, (int) val, NULL, NULL, 0)) {
switch (errno) {
case EWOULDBLOCK:
return;
case EINTR:
break; /* get out of switch and retry */
default:
abort();
}
}
}
#endif /* QEMU_FUTEX_H */