dnl #
dnl # 2.6.36 API change,
dnl # The 'struct fs_struct->lock' was changed from a rwlock_t to
dnl # a spinlock_t to improve the fastpath performance.
AC_DEFUN([ZFS_AC_KERNEL_FS_STRUCT_SPINLOCK], [
AC_MSG_CHECKING([whether struct fs_struct uses spinlock_t])
tmp_flags="$EXTRA_KCFLAGS"
EXTRA_KCFLAGS="-Werror"
ZFS_LINUX_TRY_COMPILE([
#include <linux/sched.h>
#include <linux/fs_struct.h>
],[
static struct fs_struct fs;
spin_lock_init(&fs.lock);
AC_MSG_RESULT(yes)
AC_DEFINE(HAVE_FS_STRUCT_SPINLOCK, 1,
[struct fs_struct uses spinlock_t])
AC_MSG_RESULT(no)
])
EXTRA_KCFLAGS="$tmp_flags"