vsprintf: use WARN_ON_ONCE

Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib/vsprintf.c

diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index d320c18..73a14b8 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -1092,13 +1092,8 @@
 
 	/* Reject out-of-range values early.  Large positive sizes are
 	   used for unknown buffer sizes. */
-	if (unlikely((int) size < 0)) {
-		/* There can be only one.. */
-		static char warn = 1;
-		WARN_ON(warn);
-		warn = 0;
+	if (WARN_ON_ONCE((int) size < 0))
 		return 0;
-	}
 
 	str = buf;
 	end = buf + size;
@@ -1544,13 +1539,8 @@
 
 	struct printf_spec spec = {0};
 
-	if (unlikely((int) size < 0)) {
-		/* There can be only one.. */
-		static char warn = 1;
-		WARN_ON(warn);
-		warn = 0;
+	if (WARN_ON_ONCE((int) size < 0))
 		return 0;
-	}
 
 	str = buf;
 	end = buf + size;