[src/trunk]: src/sys/net introduce if_output_lock()

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

details:   https://anonhg.NetBSD.org/src/rev/021984f91df3
branches:  trunk
changeset: 346029:021984f91df3
user:      knakahara <knakahara%NetBSD.org@localhost>
date:      Mon Jun 20 06:41:15 2016 +0000

description:
introduce if_output_lock()

if_output_lock() calls ifp->if_output() holding KERNEL_LOCK if it is required.

diffstat:

 sys/net/if.h |  26 +++++++++++++++++++++++++-
 1 files changed, 25 insertions(+), 1 deletions(-)

diffs (40 lines):

diff -r 193e603abcd2 -r 021984f91df3 sys/net/if.h
--- a/sys/net/if.h      Mon Jun 20 06:35:05 2016 +0000
+++ b/sys/net/if.h      Mon Jun 20 06:41:15 2016 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: if.h,v 1.208 2016/06/20 06:35:05 knakahara Exp $       */
+/*     $NetBSD: if.h,v 1.209 2016/06/20 06:41:15 knakahara Exp $       */
 
 /*-
  * Copyright (c) 1999, 2000, 2001 The NetBSD Foundation, Inc.
@@ -382,6 +382,30 @@
 #define        IFEF_OUTPUT_MPSAFE      0x0001  /* if_output() can run parallel */
 #define        IFEF_START_MPSAFE       0x0002  /* if_start() can run parallel */
 
+static inline bool
+if_output_is_mpsafe(struct ifnet *ifp)
+{
+
+       return ((ifp->if_extflags & IFEF_OUTPUT_MPSAFE) != 0);
+}
+
+static inline int
+if_output_lock(struct ifnet *cifp, struct ifnet *ifp, struct mbuf *m,
+    const struct sockaddr *dst, const struct rtentry *rt)
+{
+
+       if (if_output_is_mpsafe(cifp)) {
+               return (*cifp->if_output)(ifp, m, dst, rt);
+       } else {
+               int ret;
+
+               KERNEL_LOCK(1, NULL);
+               ret = (*cifp->if_output)(ifp, m, dst, rt);
+               KERNEL_UNLOCK_ONE(NULL);
+               return ret;
+       }
+}
+
 #define        IFFBITS \
     "\020\1UP\2BROADCAST\3DEBUG\4LOOPBACK\5POINTOPOINT\6NOTRAILERS" \
     "\7RUNNING\10NOARP\11PROMISC\12ALLMULTI\13OACTIVE\14SIMPLEX" \