Date: Thu, 21 Jun 2001 21:58:35 -0500 (CDT) From: Mike Silbersack <silby@silby.com> To: Bosko Milekic <bmilekic@technokratis.com> Cc: <freebsd-net@FreeBSD.ORG> Subject: Re: tcp template removal / scalability patch Message-ID: <20010621215417.K15327-200000@achilles.silby.com> In-Reply-To: <20010619173424.A8399@technokratis.com>
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[-- Attachment #1 --]
Ok, here's the updated tcp template removal patch. It's functionally the
same, which is why I'm not including an updated -stable patch. Also, I
did test it with IPv6, and it seems good. No IPSEC testing, but I see no
reason why it would break if v4/v6 didn't.
What did change:
- Formatting all fixed (most of the problems were due to my hasty -stable
patch. The -current patch was less quirky.)
- t_template has been replaced with unused in the tcpcb to make sure
nobody uses it accidently. I renamed rather than removed it because
removal would probably break userland tools expecting the existing
structure.
- All t_templates = NULLs and checks to make sure it was null have been
removed.
I think it's ready for commit now, please review.
Thanks,
Mike "Silby" Silbersack
[-- Attachment #2 --]
diff -u -r netinet.old/tcp_input.c netinet/tcp_input.c
--- netinet.old/tcp_input.c Mon Jun 18 20:45:07 2001
+++ netinet/tcp_input.c Wed Jun 20 15:17:43 2001
@@ -1127,12 +1127,6 @@
}
FREE(sin, M_SONAME);
}
- tp->t_template = tcp_template(tp);
- if (tp->t_template == 0) {
- tp = tcp_drop(tp, ENOBUFS);
- dropsocket = 0; /* socket is already gone */
- goto drop;
- }
if ((taop = tcp_gettaocache(inp)) == NULL) {
taop = &tao_noncached;
bzero(taop, sizeof(*taop));
diff -u -r netinet.old/tcp_output.c netinet/tcp_output.c
--- netinet.old/tcp_output.c Mon Jun 18 20:45:07 2001
+++ netinet/tcp_output.c Thu Jun 21 21:37:57 2001
@@ -632,16 +632,11 @@
m->m_len = hdrlen;
}
m->m_pkthdr.rcvif = (struct ifnet *)0;
- if (tp->t_template == 0)
- panic("tcp_output");
#ifdef INET6
if (isipv6) {
ip6 = mtod(m, struct ip6_hdr *);
th = (struct tcphdr *)(ip6 + 1);
- bcopy((caddr_t)tp->t_template->tt_ipgen, (caddr_t)ip6,
- sizeof(struct ip6_hdr));
- bcopy((caddr_t)&tp->t_template->tt_t, (caddr_t)th,
- sizeof(struct tcphdr));
+ tcp_fillheaders(tp, ip6, th);
} else
#endif /* INET6 */
{
@@ -649,10 +644,7 @@
ipov = (struct ipovly *)ip;
th = (struct tcphdr *)(ip + 1);
/* this picks up the pseudo header (w/o the length) */
- bcopy((caddr_t)tp->t_template->tt_ipgen, (caddr_t)ip,
- sizeof(struct ip));
- bcopy((caddr_t)&tp->t_template->tt_t, (caddr_t)th,
- sizeof(struct tcphdr));
+ tcp_fillheaders(tp, ip, th);
}
/*
diff -u -r netinet.old/tcp_subr.c netinet/tcp_subr.c
--- netinet.old/tcp_subr.c Mon Jun 18 20:45:07 2001
+++ netinet/tcp_subr.c Thu Jun 21 21:43:39 2001
@@ -218,31 +218,24 @@
}
/*
- * Create template to be used to send tcp packets on a connection.
- * Call after host entry created, allocates an mbuf and fills
- * in a skeletal tcp/ip header, minimizing the amount of work
- * necessary when the connection is used.
+ * Fill in the IP and TCP headers for an outgoing packet, given the tcpcb.
+ * tcp_template used to store this data in mbufs, but we now recopy it out
+ * of the tcpcb each time to conserve mbufs.
*/
-struct tcptemp *
-tcp_template(tp)
+void
+tcp_fillheaders(tp, ip_ptr, tcp_ptr)
struct tcpcb *tp;
+ void *ip_ptr;
+ void *tcp_ptr;
{
- register struct inpcb *inp = tp->t_inpcb;
- register struct mbuf *m;
- register struct tcptemp *n;
+ struct inpcb *inp = tp->t_inpcb;
+ struct tcphdr *tcp_hdr = (struct tcphdr *)tcp_ptr;
- if ((n = tp->t_template) == 0) {
- m = m_get(M_DONTWAIT, MT_HEADER);
- if (m == NULL)
- return (0);
- m->m_len = sizeof (struct tcptemp);
- n = mtod(m, struct tcptemp *);
- }
#ifdef INET6
if ((inp->inp_vflag & INP_IPV6) != 0) {
- register struct ip6_hdr *ip6;
+ struct ip6_hdr *ip6;
- ip6 = (struct ip6_hdr *)n->tt_ipgen;
+ ip6 = (struct ip6_hdr *)ip_ptr;
ip6->ip6_flow = (ip6->ip6_flow & ~IPV6_FLOWINFO_MASK) |
(inp->in6p_flowinfo & IPV6_FLOWINFO_MASK);
ip6->ip6_vfc = (ip6->ip6_vfc & ~IPV6_VERSION_MASK) |
@@ -251,29 +244,51 @@
ip6->ip6_plen = sizeof(struct tcphdr);
ip6->ip6_src = inp->in6p_laddr;
ip6->ip6_dst = inp->in6p_faddr;
- n->tt_t.th_sum = 0;
+ tcp_hdr->th_sum = 0;
} else
#endif
- {
- struct ip *ip = (struct ip *)n->tt_ipgen;
+ {
+ struct ip *ip = (struct ip *) ip_ptr;
- bzero(ip, sizeof(struct ip)); /* XXX overkill? */
+ bzero(ip, sizeof(struct ip)); /* XXX overkill? */
ip->ip_vhl = IP_VHL_BORING;
ip->ip_p = IPPROTO_TCP;
ip->ip_src = inp->inp_laddr;
ip->ip_dst = inp->inp_faddr;
- n->tt_t.th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr,
- htons(sizeof(struct tcphdr) + IPPROTO_TCP));
- }
- n->tt_t.th_sport = inp->inp_lport;
- n->tt_t.th_dport = inp->inp_fport;
- n->tt_t.th_seq = 0;
- n->tt_t.th_ack = 0;
- n->tt_t.th_x2 = 0;
- n->tt_t.th_off = 5;
- n->tt_t.th_flags = 0;
- n->tt_t.th_win = 0;
- n->tt_t.th_urp = 0;
+ tcp_hdr->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr,
+ htons(sizeof(struct tcphdr) + IPPROTO_TCP));
+ }
+
+ tcp_hdr->th_sport = inp->inp_lport;
+ tcp_hdr->th_dport = inp->inp_fport;
+ tcp_hdr->th_seq = 0;
+ tcp_hdr->th_ack = 0;
+ tcp_hdr->th_x2 = 0;
+ tcp_hdr->th_off = 5;
+ tcp_hdr->th_flags = 0;
+ tcp_hdr->th_win = 0;
+ tcp_hdr->th_urp = 0;
+}
+
+/*
+ * Create template to be used to send tcp packets on a connection.
+ * Allocates an mbuf and fills in a skeletal tcp/ip header. The only
+ * use for this function is in keepalives, which use tcp_respond.
+ */
+struct tcptemp *
+tcp_maketemplate(tp)
+ struct tcpcb *tp;
+{
+ struct mbuf *m;
+ struct tcptemp *n;
+
+ m = m_get(M_DONTWAIT, MT_HEADER);
+ if (m == NULL)
+ return (0);
+ m->m_len = sizeof(struct tcptemp);
+ n = mtod(m, struct tcptemp *);
+
+ tcp_fillheaders(tp, (void *)&n->tt_ipgen, (void *)&n->tt_t);
return (n);
}
@@ -282,10 +297,9 @@
* the given TCP/IP header. If m == 0, then we make a copy
* of the tcpiphdr at ti and send directly to the addressed host.
* This is used to force keep alive messages out using the TCP
- * template for a connection tp->t_template. If flags are given
- * then we send a message back to the TCP which originated the
- * segment ti, and discard the mbuf containing it and any other
- * attached mbufs.
+ * template for a connection. If flags are given then we send
+ * a message back to the TCP which originated the * segment ti,
+ * and discard the mbuf containing it and any other attached mbufs.
*
* In any case the ack and sequence number of the transmitted
* segment are as specified by the parameters.
@@ -701,8 +715,6 @@
m_freem(q->tqe_m);
FREE(q, M_TSEGQ);
}
- if (tp->t_template)
- (void) m_free(dtom(tp->t_template));
inp->inp_ppcb = NULL;
soisdisconnected(so);
#ifdef INET6
@@ -1339,7 +1351,7 @@
#endif /* INET6 */
struct tcphdr *th;
- if (!tp || !tp->t_template || !(inp = tp->t_inpcb))
+ if ((tp == NULL) || ((inp = tp->t_inpcb) == NULL))
return 0;
MGETHDR(m, M_DONTWAIT, MT_DATA);
if (!m)
@@ -1351,10 +1363,7 @@
th = (struct tcphdr *)(ip6 + 1);
m->m_pkthdr.len = m->m_len =
sizeof(struct ip6_hdr) + sizeof(struct tcphdr);
- bcopy((caddr_t)tp->t_template->tt_ipgen, (caddr_t)ip6,
- sizeof(struct ip6_hdr));
- bcopy((caddr_t)&tp->t_template->tt_t, (caddr_t)th,
- sizeof(struct tcphdr));
+ tcp_fillheaders(tp, ip6, th);
hdrsiz = ipsec6_hdrsiz(m, IPSEC_DIR_OUTBOUND, inp);
} else
#endif /* INET6 */
@@ -1362,10 +1371,7 @@
ip = mtod(m, struct ip *);
th = (struct tcphdr *)(ip + 1);
m->m_pkthdr.len = m->m_len = sizeof(struct tcpiphdr);
- bcopy((caddr_t)tp->t_template->tt_ipgen, (caddr_t)ip,
- sizeof(struct ip));
- bcopy((caddr_t)&tp->t_template->tt_t, (caddr_t)th,
- sizeof(struct tcphdr));
+ tcp_fillheaders(tp, ip, th);
ip->ip_vhl = IP_VHL_BORING;
hdrsiz = ipsec4_hdrsiz(m, IPSEC_DIR_OUTBOUND, inp);
}
Only in netinet.old/: tcp_subr.c.new
diff -u -r netinet.old/tcp_timer.c netinet/tcp_timer.c
--- netinet.old/tcp_timer.c Mon Jun 18 20:45:07 2001
+++ netinet/tcp_timer.c Thu Jun 21 21:43:59 2001
@@ -41,6 +41,7 @@
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
+#include <sys/mbuf.h>
#include <sys/sysctl.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
@@ -222,6 +223,7 @@
void *xtp;
{
struct tcpcb *tp = xtp;
+ struct tcptemp *t_template;
int s;
#ifdef TCPDEBUG
int ostate;
@@ -259,9 +261,13 @@
* correspondent TCP to respond.
*/
tcpstat.tcps_keepprobe++;
- tcp_respond(tp, tp->t_template->tt_ipgen,
- &tp->t_template->tt_t, (struct mbuf *)NULL,
- tp->rcv_nxt, tp->snd_una - 1, 0);
+ t_template = tcp_maketemplate(tp);
+ if (t_template) {
+ tcp_respond(tp, t_template->tt_ipgen,
+ &t_template->tt_t, (struct mbuf *)NULL,
+ tp->rcv_nxt, tp->snd_una - 1, 0);
+ (void) m_free(dtom(t_template));
+ }
callout_reset(tp->tt_keep, tcp_keepintvl, tcp_timer_keep, tp);
} else
callout_reset(tp->tt_keep, tcp_keepidle, tcp_timer_keep, tp);
diff -u -r netinet.old/tcp_usrreq.c netinet/tcp_usrreq.c
--- netinet.old/tcp_usrreq.c Mon Jun 18 20:45:07 2001
+++ netinet/tcp_usrreq.c Wed Jun 20 15:18:33 2001
@@ -749,12 +749,6 @@
inp->inp_fport = sin->sin_port;
in_pcbrehash(inp);
- tp->t_template = tcp_template(tp);
- if (tp->t_template == 0) {
- in_pcbdisconnect(inp);
- return ENOBUFS;
- }
-
/* Compute window scaling to request. */
while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
(TCP_MAXWIN << tp->request_r_scale) < so->so_rcv.sb_hiwat)
@@ -840,12 +834,6 @@
if ((sin6->sin6_flowinfo & IPV6_FLOWINFO_MASK) != NULL)
inp->in6p_flowinfo = sin6->sin6_flowinfo;
in_pcbrehash(inp);
-
- tp->t_template = tcp_template(tp);
- if (tp->t_template == 0) {
- in6_pcbdisconnect(inp);
- return ENOBUFS;
- }
/* Compute window scaling to request. */
while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
diff -u -r netinet.old/tcp_var.h netinet/tcp_var.h
--- netinet.old/tcp_var.h Mon Jun 18 20:45:07 2001
+++ netinet/tcp_var.h Wed Jun 20 15:17:31 2001
@@ -66,7 +66,7 @@
struct tcpcb {
struct tsegqe_head t_segq;
int t_dupacks; /* consecutive dup acks recd */
- struct tcptemp *t_template; /* skeletal packet for transmit */
+ struct tcptemp *unused; /* unused */
struct callout *tt_rexmt; /* retransmit timer */
struct callout *tt_persist; /* retransmit persistence */
@@ -400,7 +400,8 @@
void tcp_setpersist __P((struct tcpcb *));
void tcp_slowtimo __P((void));
struct tcptemp *
- tcp_template __P((struct tcpcb *));
+ tcp_maketemplate __P((struct tcpcb *));
+void tcp_fillheaders __P((struct tcpcb *, void *, void *));
struct tcpcb *
tcp_timers __P((struct tcpcb *, int));
void tcp_trace __P((int, int, struct tcpcb *, void *, struct tcphdr *,
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