Module Name: src
Committed By: tls
Date: Thu Apr 1 01:23:32 UTC 2010
Modified Files:
src/sys/netinet: ip_input.c
Log Message:
As suggested by at least 3 different people (the guilty parties know who
they are) avoid repeated kernel_lock/unlock by using an intrq on the stack.
About 5%-10% better from run to run, on my *very* simpleminded test. Can't
possibly be worse.
To generate a diff of this commit:
cvs rdiff -u -r1.285 -r1.286 src/sys/netinet/ip_input.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/netinet/ip_input.c
diff -u src/sys/netinet/ip_input.c:1.285 src/sys/netinet/ip_input.c:1.286
--- src/sys/netinet/ip_input.c:1.285 Wed Mar 31 07:31:15 2010
+++ src/sys/netinet/ip_input.c Thu Apr 1 01:23:32 2010
@@ -1,4 +1,4 @@
-/* $NetBSD: ip_input.c,v 1.285 2010/03/31 07:31:15 tls Exp $ */
+/* $NetBSD: ip_input.c,v 1.286 2010/04/01 01:23:32 tls Exp $ */
/*
* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
@@ -91,7 +91,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: ip_input.c,v 1.285 2010/03/31 07:31:15 tls Exp $");
+__KERNEL_RCSID(0, "$NetBSD: ip_input.c,v 1.286 2010/04/01 01:23:32 tls Exp $");
#include "opt_inet.h"
#include "opt_compat_netbsd.h"
@@ -231,6 +231,7 @@
int in_multientries; /* total number of addrs */
struct in_multihashhead *in_multihashtbl;
struct ifqueue ipintrq;
+
uint16_t ip_id;
percpu_t *ipstat_percpu;
@@ -474,20 +475,35 @@
{
int s;
struct mbuf *m;
+ struct ifqueue lcl_intrq;
+
+ memset(&lcl_intrq, 0, sizeof(lcl_intrq));
+ ipintrq.ifq_maxlen = ipqmaxlen;
mutex_enter(softnet_lock);
KERNEL_LOCK(1, NULL);
- while (!IF_IS_EMPTY(&ipintrq)) {
+ if (!IF_IS_EMPTY(&ipintrq)) {
s = splnet();
- IF_DEQUEUE(&ipintrq, m);
+
+ /* Take existing queue onto stack */
+ lcl_intrq = ipintrq;
+
+ /* Zero out global queue, preserving maxlen and drops */
+ ipintrq.ifq_head = NULL;
+ ipintrq.ifq_tail = NULL;
+ ipintrq.ifq_len = 0;
+ ipintrq.ifq_maxlen = lcl_intrq.ifq_maxlen;
+ ipintrq.ifq_drops = lcl_intrq.ifq_drops;
+
splx(s);
+ }
+ KERNEL_UNLOCK_ONE(NULL);
+ while (!IF_IS_EMPTY(&lcl_intrq)) {
+ IF_DEQUEUE(&lcl_intrq, m);
if (m == NULL)
break;
- KERNEL_UNLOCK_ONE(NULL);
ip_input(m);
- KERNEL_LOCK(1, NULL);
}
- KERNEL_UNLOCK_ONE(NULL);
mutex_exit(softnet_lock);
}
