diff options
| -rw-r--r-- | sys/netinet/ip_dummynet.c | 67 |
1 files changed, 62 insertions, 5 deletions
diff --git a/sys/netinet/ip_dummynet.c b/sys/netinet/ip_dummynet.c index eb0571b..930199b 100644 --- a/sys/netinet/ip_dummynet.c +++ b/sys/netinet/ip_dummynet.c @@ -91,7 +91,7 @@ static dn_key curr_time = 0 ; /* current simulation time */ static int dn_hash_size = 64 ; /* default hash size */ /* statistics on number of queue searches and search steps */ -static int searches, search_steps ; +static long searches, search_steps ; static int pipe_expire = 1 ; /* expire queue if empty */ static int dn_max_ratio = 16 ; /* max queues/buckets ratio */ @@ -99,6 +99,15 @@ static int red_lookup_depth = 256; /* RED - default lookup table depth */ static int red_avg_pkt_size = 512; /* RED - default medium packet size */ static int red_max_pkt_size = 1500; /* RED - default max packet size */ +static struct timeval prev_t, t; +static long tick_last; /* Last tick duration (usec). */ +static long tick_delta; /* Last vs standard tick diff (usec). */ +static long tick_delta_sum; /* Accumulated tick difference (usec).*/ +static long tick_adjustment; /* Tick adjustments done. */ +static long tick_lost; /* Lost(coalesced) ticks number. */ +/* Adjusted vs non-adjusted curr_time difference (ticks). */ +static long tick_diff; + /* * Three heaps contain queues and pipes that the scheduler handles: * @@ -137,15 +146,15 @@ extern void (*bridge_dn_p)(struct mbuf *, struct ifnet *); SYSCTL_NODE(_net_inet_ip, OID_AUTO, dummynet, CTLFLAG_RW, 0, "Dummynet"); SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, hash_size, CTLFLAG_RW, &dn_hash_size, 0, "Default hash table size"); -SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, curr_time, +SYSCTL_LONG(_net_inet_ip_dummynet, OID_AUTO, curr_time, CTLFLAG_RD, &curr_time, 0, "Current tick"); SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, ready_heap, CTLFLAG_RD, &ready_heap.size, 0, "Size of ready heap"); SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, extract_heap, CTLFLAG_RD, &extract_heap.size, 0, "Size of extract heap"); -SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, searches, +SYSCTL_LONG(_net_inet_ip_dummynet, OID_AUTO, searches, CTLFLAG_RD, &searches, 0, "Number of queue searches"); -SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, search_steps, +SYSCTL_LONG(_net_inet_ip_dummynet, OID_AUTO, search_steps, CTLFLAG_RD, &search_steps, 0, "Number of queue search steps"); SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, expire, CTLFLAG_RW, &pipe_expire, 0, "Expire queue if empty"); @@ -158,6 +167,18 @@ SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, red_avg_pkt_size, CTLFLAG_RD, &red_avg_pkt_size, 0, "RED Medium packet size"); SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, red_max_pkt_size, CTLFLAG_RD, &red_max_pkt_size, 0, "RED Max packet size"); +SYSCTL_LONG(_net_inet_ip_dummynet, OID_AUTO, tick_delta, + CTLFLAG_RD, &tick_delta, 0, "Last vs standard tick difference (usec)."); +SYSCTL_LONG(_net_inet_ip_dummynet, OID_AUTO, tick_delta_sum, + CTLFLAG_RD, &tick_delta_sum, 0, "Accumulated tick difference (usec)."); +SYSCTL_LONG(_net_inet_ip_dummynet, OID_AUTO, tick_adjustment, + CTLFLAG_RD, &tick_adjustment, 0, "Tick adjustments done."); +SYSCTL_LONG(_net_inet_ip_dummynet, OID_AUTO, tick_diff, + CTLFLAG_RD, &tick_diff, 0, + "Adjusted vs non-adjusted curr_time difference (ticks)."); +SYSCTL_LONG(_net_inet_ip_dummynet, OID_AUTO, tick_lost, + CTLFLAG_RD, &tick_lost, 0, + "Number of ticks coalesced by dummynet taskqueue."); #endif #ifdef DUMMYNET_DEBUG @@ -728,7 +749,40 @@ dummynet_task(void *context, int pending) heaps[1] = &wfq_ready_heap; /* wfq queues */ heaps[2] = &extract_heap; /* delay line */ - curr_time++; + /* Update number of lost(coalesced) ticks. */ + tick_lost += pending - 1; + + getmicrouptime(&t); + /* Last tick duration (usec). */ + tick_last = (t.tv_sec - prev_t.tv_sec) * 1000000 + + (t.tv_usec - prev_t.tv_usec); + /* Last tick vs standard tick difference (usec). */ + tick_delta = (tick_last * hz - 1000000) / hz; + /* Accumulated tick difference (usec). */ + tick_delta_sum += tick_delta; + + prev_t = t; + + /* + * Adjust curr_time if accumulated tick difference greater than + * 'standard' tick. Since curr_time should be monotonically increasing, + * we do positive adjustment as required and throttle curr_time in + * case of negative adjustment. + */ + curr_time++; + if (tick_delta_sum - tick >= 0) { + int diff = tick_delta_sum / tick; + + curr_time += diff; + tick_diff += diff; + tick_delta_sum %= tick; + tick_adjustment++; + } else if (tick_delta_sum + tick <= 0) { + curr_time--; + tick_diff--; + tick_delta_sum += tick; + tick_adjustment++; + } for (i = 0; i < 3; i++) { h = heaps[i]; @@ -2091,6 +2145,9 @@ ip_dn_init(void) callout_init(&dn_timeout, NET_CALLOUT_MPSAFE); callout_reset(&dn_timeout, 1, dummynet, NULL); + + /* Initialize curr_time adjustment mechanics. */ + getmicrouptime(&prev_t); } #ifdef KLD_MODULE |
