Implement a proper rw_tryupgrade

[mirror_spl.git] / config / spl-build.m4

diff --git a/config/spl-build.m4 b/config/spl-build.m4
index 720506959f0b2789ad4e7f2be68ce130624d8315..d705c6531babb414a3b4da198de0562d05472fc4 100644 (file)
--- a/config/spl-build.m4
+++ b/config/spl-build.m4
@@ -39,6 +39,7 @@ AC_DEFUN([SPL_AC_CONFIG_KERNEL], [
        SPL_AC_2ARGS_ZLIB_DEFLATE_WORKSPACESIZE
        SPL_AC_SHRINK_CONTROL_STRUCT
        SPL_AC_RWSEM_SPINLOCK_IS_RAW
+       SPL_AC_RWSEM_ACTIVITY
        SPL_AC_SCHED_RT_HEADER
        SPL_AC_2ARGS_VFS_GETATTR
        SPL_AC_USLEEP_RANGE
@@ -1316,6 +1317,30 @@ AC_DEFUN([SPL_AC_RWSEM_SPINLOCK_IS_RAW], [
        EXTRA_KCFLAGS="$tmp_flags"
 ])
 
+dnl #
+dnl # 3.16 API Change
+dnl #
+dnl # rwsem-spinlock "->activity" changed to "->count"
+dnl #
+AC_DEFUN([SPL_AC_RWSEM_ACTIVITY], [
+       AC_MSG_CHECKING([whether struct rw_semaphore has member activity])
+       tmp_flags="$EXTRA_KCFLAGS"
+       EXTRA_KCFLAGS="-Werror"
+       SPL_LINUX_TRY_COMPILE([
+               #include <linux/rwsem.h>
+       ],[
+               struct rw_semaphore dummy_semaphore __attribute__ ((unused));
+               dummy_semaphore.activity = 0;
+       ],[
+               AC_MSG_RESULT(yes)
+               AC_DEFINE(HAVE_RWSEM_ACTIVITY, 1,
+               [struct rw_semaphore has member activity])
+       ],[
+               AC_MSG_RESULT(no)
+       ])
+       EXTRA_KCFLAGS="$tmp_flags"
+])
+
 dnl #
 dnl # 3.9 API change,
 dnl # Moved things from linux/sched.h to linux/sched/rt.h