diff --git a/include/asm-generic/siginfo.h b/include/asm-generic/siginfo.h
index 9cac8e8..8786e01 100644
--- a/include/asm-generic/siginfo.h
+++ b/include/asm-generic/siginfo.h
@@ -236,11 +236,18 @@
 #define SIGEV_THREAD	2	/* deliver via thread creation */
 #define SIGEV_THREAD_ID 4	/* deliver to thread */
 
-#define SIGEV_MAX_SIZE	64
-#ifndef SIGEV_PAD_SIZE
-#define SIGEV_PAD_SIZE	((SIGEV_MAX_SIZE/sizeof(int)) - 3)
+/*
+ * This works because the alignment is ok on all current architectures
+ * but we leave open this being overridden in the future
+ */
+#ifndef __ARCH_SIGEV_PREAMBLE_SIZE
+#define __ARCH_SIGEV_PREAMBLE_SIZE	(sizeof(int) * 2 + sizeof(sigval_t))
 #endif
 
+#define SIGEV_MAX_SIZE	64
+#define SIGEV_PAD_SIZE	((SIGEV_MAX_SIZE - __ARCH_SIGEV_PREAMBLE_SIZE) \
+		/ sizeof(int))
+
 typedef struct sigevent {
 	sigval_t sigev_value;
 	int sigev_signo;