Date: Mon, 19 Dec 2005 17:45:39 +0300 From: Gleb Smirnoff <glebius@FreeBSD.org> To: net@FreeBSD.org Cc: sam@FreeBSD.org Subject: allocate VLAN tags from UMA Message-ID: <20051219144539.GY41381@FreeBSD.org>
next in thread | raw e-mail | index | archive | help
--ZJcv+A0YCCLh2VIg
Content-Type: text/plain; charset=koi8-r
Content-Disposition: inline
Colleagues,
I've made a patch, implementing Sam's advice to allocate VLAN
tags for hwvlantagging capable drivers from UMA zone.
The patch gives 6% improvement on a singlethreaded UDP flood. Unfortunately
I don't have enough hardware to test it under two simultaneous floods. It
probably should give even more improvement in this case.
x head-flood
+ mtag-flood
+--------------------------------------------------------------------------+
|x x x x x x + + + ++ +|
| |____________A___M________| |________A___M____| |
+--------------------------------------------------------------------------+
N Min Max Median Avg Stddev
x 6 242001 253604 250265 248885.17 4568.0712
+ 6 258408 267557 264955 263794.5 3132.2551
Difference at 95.0% confidence
14909.3 +/- 5037.97
5.99045% +/- 2.02421%
(Student's t, pooled s = 3916.52)
The problem with the patch is the namespace pollution - vlan UMA zone
is declared in kern_mbuf.c and mtag cookie is declared in mbuf.h. I can't
make then private to if_vlan.c, because this will make NIC drivers dependent
on vlan(4).
Can we accept this?
--
Totus tuus, Glebius.
GLEBIUS-RIPN GLEB-RIPE
--ZJcv+A0YCCLh2VIg
Content-Type: text/plain; charset=koi8-r
Content-Disposition: attachment; filename=vlan-uma-mtag
Index: sys/mbuf.h
===================================================================
RCS file: /home/ncvs/src/sys/sys/mbuf.h,v
retrieving revision 1.184
diff -u -r1.184 mbuf.h
--- sys/mbuf.h 10 Dec 2005 15:21:04 -0000 1.184
+++ sys/mbuf.h 19 Dec 2005 13:07:05 -0000
@@ -758,6 +758,10 @@
#define PACKET_TAG_IPOPTIONS 27 /* Saved IP options */
#define PACKET_TAG_CARP 28 /* CARP info */
+/* Specific cookies and tags. */
+#define MTAG_VLAN 1035328035
+#define MTAG_VLAN_TAG 0 /* tag of VLAN interface */
+
/* Packet tag routines. */
struct m_tag *m_tag_alloc(u_int32_t, int, int, int);
void m_tag_delete(struct mbuf *, struct m_tag *);
@@ -768,6 +772,9 @@
int m_tag_copy_chain(struct mbuf *, struct mbuf *, int);
void m_tag_delete_nonpersistent(struct mbuf *);
+/* Specific tags routines. */
+struct m_tag *mt_vlan_alloc(int flags);
+
/*
* Initialize the list of tags associated with an mbuf.
*/
Index: kern/kern_mbuf.c
===================================================================
RCS file: /home/ncvs/src/sys/kern/kern_mbuf.c,v
retrieving revision 1.17
diff -u -r1.17 kern_mbuf.c
--- kern/kern_mbuf.c 10 Dec 2005 15:21:04 -0000 1.17
+++ kern/kern_mbuf.c 19 Dec 2005 13:06:17 -0000
@@ -133,6 +133,7 @@
uma_zone_t zone_jumbo9;
uma_zone_t zone_jumbo16;
uma_zone_t zone_ext_refcnt;
+uma_zone_t zone_mtag_vlan;
/*
* Local prototypes.
@@ -225,6 +226,12 @@
NULL, NULL,
UMA_ALIGN_PTR, UMA_ZONE_ZINIT);
+ zone_mtag_vlan = uma_zcreate("mtag_vlan",
+ sizeof(struct m_tag) + sizeof(u_int),
+ NULL, NULL,
+ NULL, NULL,
+ UMA_ALIGN_INT, 0);
+
/* uma_prealloc() goes here... */
/*
@@ -511,6 +518,25 @@
return (0);
}
+static void
+mt_vlan_free(struct m_tag *mtag)
+{
+ uma_zfree(zone_mtag_vlan, mtag);
+}
+
+struct m_tag *
+mt_vlan_alloc(int flags)
+{
+ struct m_tag *mtag;
+
+ mtag = uma_zalloc(zone_mtag_vlan, flags);
+ if (mtag) {
+ m_tag_setup(mtag, MTAG_VLAN, MTAG_VLAN_TAG, sizeof(u_int));
+ mtag->m_tag_free = mt_vlan_free;
+ }
+ return (mtag);
+}
+
/*
* This is the protocol drain routine.
*
Index: net/if_vlan.c
===================================================================
RCS file: /home/ncvs/src/sys/net/if_vlan.c,v
retrieving revision 1.93
diff -u -r1.93 if_vlan.c
--- net/if_vlan.c 28 Nov 2005 12:46:35 -0000 1.93
+++ net/if_vlan.c 19 Dec 2005 12:51:23 -0000
@@ -507,10 +507,7 @@
* packet tag that holds it.
*/
if (p->if_capenable & IFCAP_VLAN_HWTAGGING) {
- struct m_tag *mtag = m_tag_alloc(MTAG_VLAN,
- MTAG_VLAN_TAG,
- sizeof(u_int),
- M_NOWAIT);
+ struct m_tag *mtag = mt_vlan_alloc(M_NOWAIT);
if (mtag == NULL) {
ifp->if_oerrors++;
m_freem(m);
Index: net/if_vlan_var.h
===================================================================
RCS file: /home/ncvs/src/sys/net/if_vlan_var.h,v
retrieving revision 1.23
diff -u -r1.23 if_vlan_var.h
--- net/if_vlan_var.h 18 Dec 2005 18:24:27 -0000 1.23
+++ net/if_vlan_var.h 19 Dec 2005 13:01:03 -0000
@@ -93,8 +93,6 @@
* Note that a driver must indicate it supports hardware VLAN
* tagging by marking IFCAP_VLAN_HWTAGGING in if_capabilities.
*/
-#define MTAG_VLAN 1035328035
-#define MTAG_VLAN_TAG 0 /* tag of VLAN interface */
/*
* This macro must expand to a lvalue so that it can be used
@@ -103,9 +101,7 @@
#define VLAN_TAG_VALUE(_mt) (*(u_int *)((_mt) + 1))
#define VLAN_INPUT_TAG(_ifp, _m, _t) do { \
- struct m_tag *mtag; \
- mtag = m_tag_alloc(MTAG_VLAN, MTAG_VLAN_TAG, \
- sizeof (u_int), M_NOWAIT); \
+ struct m_tag *mtag = mt_vlan_alloc(M_NOWAIT); \
if (mtag != NULL) { \
VLAN_TAG_VALUE(mtag) = (_t); \
m_tag_prepend((_m), mtag); \
--ZJcv+A0YCCLh2VIg--
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20051219144539.GY41381>