diff options
Diffstat (limited to 'config')
| -rw-r--r-- | config/spl-build.m4 | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/config/spl-build.m4 b/config/spl-build.m4 index facaf7404..0b9f8f430 100644 --- a/config/spl-build.m4 +++ b/config/spl-build.m4 @@ -77,6 +77,7 @@ AC_DEFUN([SPL_AC_CONFIG_KERNEL], [ SPL_AC_5ARGS_PROC_HANDLER SPL_AC_KVASPRINTF SPL_AC_3ARGS_FILE_FSYNC + SPL_AC_EXPORTED_RWSEM_IS_LOCKED ]) AC_DEFUN([SPL_AC_MODULE_SYMVERS], [ @@ -1598,3 +1599,19 @@ AC_DEFUN([SPL_AC_3ARGS_FILE_FSYNC], [ AC_MSG_RESULT(no) ]) ]) + +dnl # +dnl # 2.6.33 API change. Also backported in RHEL5 as of 2.6.18-190.el5. +dnl # Earlier versions of rwsem_is_locked() were inline and had a race +dnl # condition. The fixed version is exported as a symbol. The race +dnl # condition is fixed by acquiring sem->wait_lock, so we must not +dnl # call that version while holding sem->wait_lock. +dnl # +AC_DEFUN([SPL_AC_EXPORTED_RWSEM_IS_LOCKED], [ + SPL_CHECK_SYMBOL_EXPORT( + [rwsem_is_locked], + [lib/rwsem-spinlock.c], + [AC_DEFINE(RWSEM_IS_LOCKED_TAKES_WAIT_LOCK, 1, + [rwsem_is_locked() acquires sem->wait_lock])], + []) +]) |