PERFORCE change 123816 for review

[Peter Wemm]

http://perforce.freebsd.org/chv.cgi?CH=123816

Change 123816 by peter at peter_overcee on 2007/07/20 18:57:27

	Check in silby's tcp patch.

Affected files ...

.. //depot/projects/hammer/sys/netinet/tcp_syncache.c#44 edit

Differences ...

==== //depot/projects/hammer/sys/netinet/tcp_syncache.c#44 (text+ko) ====

@@ -142,7 +142,6 @@
 	struct mtx	sch_mtx;
 	TAILQ_HEAD(sch_head, syncache)	sch_bucket;
 	struct callout	sch_timer;
-	int		sch_nextc;
 	u_int		sch_length;
 	u_int		sch_oddeven;
 	u_int32_t	sch_secbits_odd[SYNCOOKIE_SECRET_SIZE];
@@ -233,16 +232,10 @@
 
 #define ENDPTS6_EQ(a, b) (memcmp(a, b, sizeof(*a)) == 0)
 
-#define SYNCACHE_TIMEOUT(sc, sch, co) do {				\
+#define SYNCACHE_TIMEOUT(sc) do {					\
 	(sc)->sc_rxmits++;						\
 	(sc)->sc_rxttime = ticks +					\
 		TCPTV_RTOBASE * tcp_backoff[(sc)->sc_rxmits - 1];	\
-	if ((sch)->sch_nextc > (sc)->sc_rxttime)			\
-		(sch)->sch_nextc = (sc)->sc_rxttime;			\
-	if (!TAILQ_EMPTY(&(sch)->sch_bucket) && !(co))			\
-		callout_reset(&(sch)->sch_timer,			\
-			(sch)->sch_nextc - ticks,			\
-			syncache_timer, (void *)(sch));			\
 } while (0)
 
 #define	SCH_LOCK(sch)		mtx_lock(&(sch)->sch_mtx)
@@ -268,6 +261,7 @@
 syncache_init(void)
 {
 	int i;
+	struct syncache_head *sch;
 
 	tcp_syncache.cache_count = 0;
 	tcp_syncache.hashsize = TCP_SYNCACHE_HASHSIZE;
@@ -310,6 +304,17 @@
 	tcp_syncache.zone = uma_zcreate("syncache", sizeof(struct syncache),
 	    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
 	uma_zone_set_max(tcp_syncache.zone, tcp_syncache.cache_limit);
+
+	/*
+	 * Start the syncache head timers running.  They each run ten times
+	 * a second, and are spread out so that they are not all running on
+	 * the same clock tick.
+	 */
+	for (i = 0; i < tcp_syncache.hashsize; i++) {
+		sch = &tcp_syncache.hashbase[i];
+		callout_reset(&(sch)->sch_timer, i * (hz / 10),    
+                syncache_timer, (void *)(sch));
+	}
 }
 
 /*
@@ -339,8 +344,8 @@
 	TAILQ_INSERT_HEAD(&sch->sch_bucket, sc, sc_hash);
 	sch->sch_length++;
 
-	/* Reinitialize the bucket row's timer. */
-	SYNCACHE_TIMEOUT(sc, sch, 1);
+	/* Set the retransmit timer for this socket. */
+	SYNCACHE_TIMEOUT(sc);
 
 	SCH_UNLOCK(sch);
 
@@ -391,8 +396,6 @@
 		 * host does the SYN/ACK->ACK.
 		 */
 		if (sc->sc_rxttime >= tick) {
-			if (sc->sc_rxttime < sch->sch_nextc)
-				sch->sch_nextc = sc->sc_rxttime;
 			continue;
 		}
 
@@ -409,11 +412,10 @@
 
 		(void) syncache_respond(sc);
 		tcpstat.tcps_sc_retransmitted++;
-		SYNCACHE_TIMEOUT(sc, sch, 0);
+		SYNCACHE_TIMEOUT(sc);
 	}
-	if (!TAILQ_EMPTY(&(sch)->sch_bucket))
-		callout_reset(&(sch)->sch_timer, (sch)->sch_nextc - tick,
-			syncache_timer, (void *)(sch));
+	callout_reset(&(sch)->sch_timer, hz / 10,
+		syncache_timer, (void *)(sch));
 }
 
 /*
@@ -995,7 +997,7 @@
 		    ("%s: label not initialized", __func__));
 #endif
 		if (syncache_respond(sc) == 0) {
-			SYNCACHE_TIMEOUT(sc, sch, 1);
+			SYNCACHE_TIMEOUT(sc);
 			tcpstat.tcps_sndacks++;
 			tcpstat.tcps_sndtotal++;
 		}