xenocara/lib/libxshmfence/src/xshmfence_futex.h

109 lines
2.9 KiB
C

/*
* Copyright © 2013 Keith Packard
* Copyright © 2013 Jung-uk Kim <jkim@FreeBSD.org>
*
* Permission to use, copy, modify, distribute, and sell this software and its
* documentation for any purpose is hereby granted without fee, provided that
* the above copyright notice appear in all copies and that both that copyright
* notice and this permission notice appear in supporting documentation, and
* that the name of the copyright holders not be used in advertising or
* publicity pertaining to distribution of the software without specific,
* written prior permission. The copyright holders make no representations
* about the suitability of this software for any purpose. It is provided "as
* is" without express or implied warranty.
*
* THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
* INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
* EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
* CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
* DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
* TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
* OF THIS SOFTWARE.
*/
#ifndef _XSHMFENCE_FUTEX_H_
#define _XSHMFENCE_FUTEX_H_
#include <errno.h>
#ifdef HAVE_FUTEX
#include <sys/time.h>
#include <sys/futex.h>
#include <limits.h>
static inline int futex_wake(int32_t *addr) {
return futex(addr, FUTEX_WAKE, INT_MAX, NULL, NULL);
}
static inline int futex_wait(int32_t *addr, int32_t value) {
return futex(addr, FUTEX_WAIT, value, NULL, NULL);
}
#elif HAVE_UMTX
#include <sys/types.h>
#include <sys/umtx.h>
#include <limits.h>
static inline int sys_futex(void *addr, int op, int32_t val)
{
return _umtx_op(addr, op, (uint32_t)val, NULL, NULL) == -1 ? errno : 0;
}
static inline int futex_wake(int32_t *addr) {
return sys_futex(addr, UMTX_OP_WAKE, INT_MAX);
}
static inline int futex_wait(int32_t *addr, int32_t value) {
return sys_futex(addr, UMTX_OP_WAIT_UINT, value);
}
#else
#include <stdint.h>
#include <values.h>
#include <linux/futex.h>
#include <sys/time.h>
#include <sys/syscall.h>
static inline long sys_futex(void *addr1, int op, int val1, struct timespec *timeout, void *addr2, int val3)
{
return syscall(SYS_futex, addr1, op, val1, timeout, addr2, val3);
}
static inline int futex_wake(int32_t *addr) {
return sys_futex(addr, FUTEX_WAKE, MAXINT, NULL, NULL, 0);
}
static inline int futex_wait(int32_t *addr, int32_t value) {
return sys_futex(addr, FUTEX_WAIT, value, NULL, NULL, 0);
}
#endif
#define barrier() __asm__ __volatile__("": : :"memory")
static inline void atomic_store(int32_t *f, int32_t v)
{
barrier();
*f = v;
barrier();
}
static inline int32_t atomic_fetch(int32_t *a)
{
int32_t v;
barrier();
v = *a;
barrier();
return v;
}
struct xshmfence {
int32_t v;
};
#define xshmfence_init(fd)
#endif /* _XSHMFENCE_FUTEX_H_ */