Fix HAVE_MUTEX_OWNER test for kernels prior to 4.6

Recent 4.X kernels prior to 4.6 require #include of spinlock.h in
order to get the definition of __ARCH_SPIN_LOCK_UNLOCKED which is
used by DEFINE_MUTEX().

Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #566

diff --git a/config/spl-build.m4 b/config/spl-build.m4
index 3ed0e8fd0d629c04119ceda6b56ddcea6eaa9c44..94e692a8bfedf4c32fa868f215277e3d0e67318d 100644 (file)
--- a/config/spl-build.m4
+++ b/config/spl-build.m4
@@ -1537,6 +1537,7 @@ AC_DEFUN([SPL_AC_MUTEX_OWNER], [
        EXTRA_KCFLAGS="-Werror"
        SPL_LINUX_TRY_COMPILE([
                #include <linux/mutex.h>
+               #include <linux/spinlock.h>
        ],[
                DEFINE_MUTEX(m);
                struct task_struct *t __attribute__ ((unused));