[src/trunk]: src/sys/net reduce link state changing softint if it is not requ...

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

details:   https://anonhg.NetBSD.org/src/rev/48b6cd0fccd6
branches:  trunk
changeset: 816265:48b6cd0fccd6
user:      knakahara <knakahara%NetBSD.org@localhost>
date:      Mon Jun 27 08:58:50 2016 +0000

description:
reduce link state changing softint if it is not required

ok by ozaki-r@n.o

diffstat:

 sys/net/if.c |  23 ++++++++++++++++-------
 sys/net/if.h |  14 +++++++++++---
 2 files changed, 27 insertions(+), 10 deletions(-)

diffs (93 lines):

diff -r fcdddabdafc4 -r 48b6cd0fccd6 sys/net/if.c
--- a/sys/net/if.c      Mon Jun 27 08:46:04 2016 +0000
+++ b/sys/net/if.c      Mon Jun 27 08:58:50 2016 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: if.c,v 1.345 2016/06/22 10:44:32 knakahara Exp $       */
+/*     $NetBSD: if.c,v 1.346 2016/06/27 08:58:50 knakahara Exp $       */
 
 /*-
  * Copyright (c) 1999, 2000, 2001, 2008 The NetBSD Foundation, Inc.
@@ -90,7 +90,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if.c,v 1.345 2016/06/22 10:44:32 knakahara Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if.c,v 1.346 2016/06/27 08:58:50 knakahara Exp $");
 
 #if defined(_KERNEL_OPT)
 #include "opt_inet.h"
@@ -640,9 +640,12 @@
 
        IF_AFDATA_LOCK_INIT(ifp);
 
-       ifp->if_link_si = softint_establish(SOFTINT_NET, if_link_state_change_si, ifp);
-       if (ifp->if_link_si == NULL)
-               panic("%s: softint_establish() failed", __func__);
+       if (if_is_link_state_chageable(ifp)) {
+               ifp->if_link_si = softint_establish(SOFTINT_NET,
+                   if_link_state_change_si, ifp);
+               if (ifp->if_link_si == NULL)
+                       panic("%s: softint_establish() failed", __func__);
+       }
 
        PSLIST_ENTRY_INIT(ifp, if_pslist_entry);
        psref_target_init(&ifp->if_psref, ifnet_psref_class);
@@ -1192,8 +1195,10 @@
 
        IF_AFDATA_LOCK_DESTROY(ifp);
 
-       softint_disestablish(ifp->if_link_si);
-       ifp->if_link_si = NULL;
+       if (if_is_link_state_chageable(ifp)) {
+               softint_disestablish(ifp->if_link_si);
+               ifp->if_link_si = NULL;
+       }
 
        /*
         * remove packets that came from ifp, from software interrupt queues.
@@ -1781,6 +1786,10 @@
 {
        int s, idx;
 
+       KASSERTMSG(if_is_link_state_chageable(ifp),
+           "%s: IFEF_NO_LINK_STATE_CHANGE must not be set, but if_extflags=0x%x",
+           ifp->if_xname, ifp->if_extflags);
+
        /* Ensure change is to a valid state */
        switch (link_state) {
        case LINK_STATE_UNKNOWN:        /* FALLTHROUGH */
diff -r fcdddabdafc4 -r 48b6cd0fccd6 sys/net/if.h
--- a/sys/net/if.h      Mon Jun 27 08:46:04 2016 +0000
+++ b/sys/net/if.h      Mon Jun 27 08:58:50 2016 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: if.h,v 1.215 2016/06/22 10:44:32 knakahara Exp $       */
+/*     $NetBSD: if.h,v 1.216 2016/06/27 08:58:50 knakahara Exp $       */
 
 /*-
  * Copyright (c) 1999, 2000, 2001 The NetBSD Foundation, Inc.
@@ -381,8 +381,9 @@
 #define        IFF_LINK2       0x4000          /* per link layer defined bit */
 #define        IFF_MULTICAST   0x8000          /* supports multicast */
 
-#define        IFEF_OUTPUT_MPSAFE      0x0001  /* if_output() can run parallel */
-#define        IFEF_START_MPSAFE       0x0002  /* if_start() can run parallel */
+#define        IFEF_OUTPUT_MPSAFE              __BIT(0)        /* if_output() can run parallel */
+#define        IFEF_START_MPSAFE               __BIT(1)        /* if_start() can run parallel */
+#define        IFEF_NO_LINK_STATE_CHANGE       __BIT(2)        /* doesn't use link state interrupts */
 
 #ifdef _KERNEL
 static inline bool
@@ -428,6 +429,13 @@
                KERNEL_UNLOCK_ONE(NULL);
        }
 }
+
+static inline bool
+if_is_link_state_chageable(struct ifnet *ifp)
+{
+
+       return ((ifp->if_extflags & IFEF_NO_LINK_STATE_CHANGE) == 0);
+}
 #endif /* _KERNEL */
 
 #define        IFFBITS \