[src/trunk]: src/sys/net/npf Skip npf_config_sync if nothing to do.

[riastradh <riastradh%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/43a085a2f9e3
branches:  trunk
changeset: 967554:43a085a2f9e3
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Sat Dec 14 15:21:51 2019 +0000

description:
Skip npf_config_sync if nothing to do.

Saves an unnecessary pserialize_perform every second.

diffstat:

 sys/net/npf/npf_conndb.c |  4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diffs (21 lines):

diff -r d5830cbb6f82 -r 43a085a2f9e3 sys/net/npf/npf_conndb.c
--- a/sys/net/npf/npf_conndb.c  Sat Dec 14 15:08:45 2019 +0000
+++ b/sys/net/npf/npf_conndb.c  Sat Dec 14 15:21:51 2019 +0000
@@ -46,7 +46,7 @@
 
 #ifdef _KERNEL
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: npf_conndb.c,v 1.6 2019/07/23 00:52:01 rmind Exp $");
+__KERNEL_RCSID(0, "$NetBSD: npf_conndb.c,v 1.7 2019/12/14 15:21:51 riastradh Exp $");
 
 #include <sys/param.h>
 #include <sys/types.h>
@@ -371,7 +371,7 @@
         * Note: drop the conn_lock (see the lock order).
         */
        gcref = thmap_stage_gc(cd->cd_map);
-       if (sync) {
+       if (sync && (gcref || !LIST_EMPTY(&cd->cd_gclist))) {
                npf_config_enter(npf);
                npf_config_sync(npf);
                npf_config_exit(npf);