[LTP] [PATCH 2/3] tst_test: add macro helper to invoke pthread_once()

[Alexey Kodanev]

Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com>
---
 include/tst_test.h |   14 ++++++++++++++
 1 files changed, 14 insertions(+), 0 deletions(-)

diff --git a/include/tst_test.h b/include/tst_test.h
index 3c77a98..a4ba167 100644
--- a/include/tst_test.h
+++ b/include/tst_test.h
@@ -71,6 +71,20 @@ pid_t safe_fork(const char *filename, unsigned int lineno);
 	({int ret = expr;                                           \
 	  ret != 0 ? tst_res(TINFO, #expr " failed"), ret : ret; }) \
 
+/*
+ * Macro to use for making functions called only once in
+ * multi-threaded tests such as init or cleanup function.
+ * The first call to @name_fn function by any thread shall
+ * call the @exec_fn. Subsequent calls shall not call @exec_fn.
+ * *_fn functions must not take any arguments.
+ */
+#define TST_DECLARE_ONCE_FN(name_fn, exec_fn)				\
+	void name_fn(void)						\
+	{								\
+		static pthread_once_t ltp_once = PTHREAD_ONCE_INIT;	\
+		pthread_once(&ltp_once, exec_fn);			\
+	}
+
 #include "tst_safe_macros.h"
 #include "tst_safe_file_ops.h"
 #include "tst_safe_net.h"
-- 
1.7.1