Split spl-build.m4

[mirror_spl.git] / config / kernel-spinlock.m4

diff --git a/config/kernel-spinlock.m4 b/config/kernel-spinlock.m4
new file mode 100644 (file)
index 0000000..136262d
--- /dev/null
+++ b/config/kernel-spinlock.m4
@@ -0,0 +1,24 @@
+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.
+dnl #
+AC_DEFUN([SPL_AC_FS_STRUCT_SPINLOCK], [
+       AC_MSG_CHECKING([whether struct fs_struct uses spinlock_t])
+       tmp_flags="$EXTRA_KCFLAGS"
+       EXTRA_KCFLAGS="-Werror"
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/sched.h>
+               #include <linux/fs_struct.h>
+       ],[
+               static struct fs_struct fs;
+               spin_lock_init(&fs.lock);
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_FS_STRUCT_SPINLOCK, 1,
+                         [struct fs_struct uses spinlock_t])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+       EXTRA_KCFLAGS="$tmp_flags"
+])