sys/types.h \
])
+# Verify whether the <linux/futex.h> header is usable.
+AC_MSG_CHECKING([if <linux/futex.h> is usable])
+
+AC_TRY_COMPILE([
+#include <linux/futex.h>
+], [
+ return FUTEX_WAIT;
+],
+[
+AC_DEFINE([HAVE_USABLE_LINUX_FUTEX_H], 1,
+ [Define to 1 if you have a usable <linux/futex.h> header file.])
+AC_MSG_RESULT([yes])
+], [
+AC_MSG_RESULT([no])
+])
+
#----------------------------------------------------------------------------
# Checks for typedefs, structures, and compiler characteristics.
#----------------------------------------------------------------------------
#include <stdio.h> /* fprintf() */
#include <stdlib.h> /* malloc(), free() */
#include <unistd.h> /* confstr() */
-#ifdef __linux__
+#include "config.h" /* HAVE_PTHREAD_MUTEX_ADAPTIVE_NP etc. */
+#ifdef HAVE_USABLE_LINUX_FUTEX_H
#include <asm/unistd.h> /* __NR_futex */
#include <linux/futex.h> /* FUTEX_WAIT */
#ifndef FUTEX_PRIVATE_FLAG
#define FUTEX_PRIVATE_FLAG 0
#endif
#endif
-#include "config.h" /* HAVE_PTHREAD_MUTEX_ADAPTIVE_NP etc. */
#include "drd_basics.h" /* DRD_() */
#include "drd_clientreq.h"
#include "pub_tool_redir.h" /* VG_WRAP_FUNCTION_ZZ() */
int res = ENOSYS;
while (sema->counter == 0) {
-#if defined(__linux__) && defined(__NR_futex)
+#ifdef HAVE_USABLE_LINUX_FUTEX_H
if (syscall(__NR_futex, (UWord)&sema->counter,
FUTEX_WAIT | FUTEX_PRIVATE_FLAG, 0) == 0)
res = 0;
static void DRD_(sema_up)(DrdSema* sema)
{
sema->counter++;
-#if defined(__linux__) && defined(__NR_futex)
+#ifdef HAVE_USABLE_LINUX_FUTEX_H
syscall(__NR_futex, (UWord)&sema->counter,
FUTEX_WAKE | FUTEX_PRIVATE_FLAG, 1);
#endif