From 12a7cdaeee1c9e31aafda4708bbdb309cac619d6 Mon Sep 17 00:00:00 2001
From: Sepherosa Ziehau <sephe@dragonflybsd.org>
Date: Fri, 30 Jun 2017 09:23:57 +0800
Subject: [PATCH] route: Cache align statistics.

Though these statistics are rarely updated; better safe the sorry.

Since it changes userland visible structure size, bump
__DragonFly_version.
---
 sys/net/route.c | 2 +-
 sys/net/route.h | 7 ++++++-
 sys/sys/param.h | 3 ++-
 3 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/sys/net/route.c b/sys/net/route.c
index cf376b88ec..0fbc7b4c80 100644
--- a/sys/net/route.c
+++ b/sys/net/route.c
@@ -92,7 +92,7 @@
 #include <netproto/mpls/mpls.h>
 #endif
 
-static struct rtstatistics rtstatistics_percpu[MAXCPU];
+static struct rtstatistics rtstatistics_percpu[MAXCPU] __cachealign;
 #define rtstat	rtstatistics_percpu[mycpuid]
 
 struct radix_node_head *rt_tables[MAXCPU][AF_MAX+1];
diff --git a/sys/net/route.h b/sys/net/route.h
index cf73803216..6ee8b5835d 100644
--- a/sys/net/route.h
+++ b/sys/net/route.h
@@ -209,13 +209,18 @@ struct ortentry {
 /*
  * Routing statistics.
  */
-struct	rtstatistics {
+struct rtstatistics {
 	u_long	rts_badredirect;	/* bogus redirect calls */
 	u_long	rts_dynamic;		/* routes created by redirects */
 	u_long	rts_newgateway;		/* routes modified by redirects */
 	u_long	rts_unreach;		/* lookups which failed */
 	u_long	rts_wildcard;		/* lookups satisfied by a wildcard */
+	u_long	rts_pad[3];		/* pad to cache line size (64B) */
 };
+#ifdef _KERNEL
+CTASSERT((sizeof(struct rtstatistics) & __VM_CACHELINE_MASK) == 0);
+#endif
+
 /*
  * Structures for routing messages.
  */
diff --git a/sys/sys/param.h b/sys/sys/param.h
index 6ce0753d30..49bbe40b75 100644
--- a/sys/sys/param.h
+++ b/sys/sys/param.h
@@ -153,9 +153,10 @@
  * 400901 - moved sigtramp, NX protection + associated sysctls
  * 400902 - change CPU_SETSIZE to signed; allow proc to change self affinity
  * 400903 - malloc_type cleanup
+ * 400904 - pad rtstatistics
  */
 #undef __DragonFly_version
-#define __DragonFly_version 400903	/* propagated to newvers */
+#define __DragonFly_version 400904	/* propagated to newvers */
 
 #include <sys/_null.h>
 
-- 
2.11.4.GIT