From e764773ccb007e79f44d948a781fae1313ac28fe Mon Sep 17 00:00:00 2001 From: Ben Pfaff Date: Wed, 1 Feb 2012 15:04:51 -0800 Subject: [PATCH] vswitchd: Make the MAC entry aging time configurable. NICS-11. Signed-off-by: Ben Pfaff --- NEWS | 2 ++ lib/learning-switch.c | 6 ++++-- lib/mac-learning.c | 41 +++++++++++++++++++++++++++++++------- lib/mac-learning.h | 10 +++++++--- ofproto/ofproto-dpif.c | 13 ++++++++++-- ofproto/ofproto-provider.h | 4 ++++ ofproto/ofproto.c | 10 ++++++++++ ofproto/ofproto.h | 3 ++- vswitchd/bridge.c | 17 ++++++++++++++++ vswitchd/vswitch.xml | 20 +++++++++++++++++++ 10 files changed, 111 insertions(+), 15 deletions(-) diff --git a/NEWS b/NEWS index 96fee6dd..592e0135 100644 --- a/NEWS +++ b/NEWS @@ -18,6 +18,8 @@ post-v1.5.0 - ofproto-provider interface: - "struct rule" has a new member "used" that ofproto implementations should maintain by updating with ofproto_rule_update_used(). + - The default MAC learning timeout has been increased from 60 seconds + to 300 seconds. The MAC learning timeout is now configurable. v1.5.0 - xx xxx xxxx diff --git a/lib/learning-switch.c b/lib/learning-switch.c index 3bcb9610..60cf731d 100644 --- a/lib/learning-switch.c +++ b/lib/learning-switch.c @@ -1,5 +1,5 @@ /* - * Copyright (c) 2008, 2009, 2010, 2011 Nicira Networks. + * Copyright (c) 2008, 2009, 2010, 2011, 2012 Nicira Networks. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. @@ -97,7 +97,9 @@ lswitch_create(struct rconn *rconn, const struct lswitch_config *cfg) sw->max_idle = cfg->max_idle; sw->datapath_id = 0; sw->last_features_request = time_now() - 1; - sw->ml = cfg->mode == LSW_LEARN ? mac_learning_create() : NULL; + sw->ml = (cfg->mode == LSW_LEARN + ? mac_learning_create(MAC_ENTRY_DEFAULT_IDLE_TIME) + : NULL); sw->action_normal = cfg->mode == LSW_NORMAL; flow_wildcards_init_exact(&sw->wc); diff --git a/lib/mac-learning.c b/lib/mac-learning.c index 7872e2b9..e0618c2e 100644 --- a/lib/mac-learning.c +++ b/lib/mac-learning.c @@ -1,5 +1,5 @@ /* - * Copyright (c) 2008, 2009, 2010, 2011 Nicira Networks. + * Copyright (c) 2008, 2009, 2010, 2011, 2012 Nicira Networks. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. @@ -37,12 +37,12 @@ VLOG_DEFINE_THIS_MODULE(mac_learning); COVERAGE_DEFINE(mac_learning_learned); COVERAGE_DEFINE(mac_learning_expired); -/* Returns the number of seconds since 'e' was last learned. */ +/* Returns the number of seconds since 'e' (within 'ml') was last learned. */ int -mac_entry_age(const struct mac_entry *e) +mac_entry_age(const struct mac_learning *ml, const struct mac_entry *e) { time_t remaining = e->expires - time_now(); - return MAC_ENTRY_IDLE_TIME - remaining; + return ml->idle_time - remaining; } static uint32_t @@ -98,9 +98,18 @@ get_lru(struct mac_learning *ml, struct mac_entry **e) } } -/* Creates and returns a new MAC learning table. */ +static unsigned int +normalize_idle_time(unsigned int idle_time) +{ + return (idle_time < 15 ? 15 + : idle_time > 3600 ? 3600 + : idle_time); +} + +/* Creates and returns a new MAC learning table with an initial MAC aging + * timeout of 'idle_time' seconds. */ struct mac_learning * -mac_learning_create(void) +mac_learning_create(unsigned int idle_time) { struct mac_learning *ml; @@ -109,6 +118,7 @@ mac_learning_create(void) hmap_init(&ml->table); ml->secret = random_uint32(); ml->flood_vlans = NULL; + ml->idle_time = normalize_idle_time(idle_time); return ml; } @@ -146,6 +156,23 @@ mac_learning_set_flood_vlans(struct mac_learning *ml, } } +/* Changes the MAC aging timeout of 'ml' to 'idle_time' seconds. */ +void +mac_learning_set_idle_time(struct mac_learning *ml, unsigned int idle_time) +{ + idle_time = normalize_idle_time(idle_time); + if (idle_time != ml->idle_time) { + struct mac_entry *e; + int delta; + + delta = (int) idle_time - (int) ml->idle_time; + LIST_FOR_EACH (e, lru_node, &ml->lrus) { + e->expires += delta; + } + ml->idle_time = idle_time; + } +} + static bool is_learning_vlan(const struct mac_learning *ml, uint16_t vlan) { @@ -199,7 +226,7 @@ mac_learning_insert(struct mac_learning *ml, /* Mark 'e' as recently used. */ list_push_back(&ml->lrus, &e->lru_node); - e->expires = time_now() + MAC_ENTRY_IDLE_TIME; + e->expires = time_now() + ml->idle_time; return e; } diff --git a/lib/mac-learning.h b/lib/mac-learning.h index 1ae9ea5d..df8ea90e 100644 --- a/lib/mac-learning.h +++ b/lib/mac-learning.h @@ -24,10 +24,12 @@ #include "tag.h" #include "timeval.h" +struct mac_learning; + #define MAC_MAX 2048 /* Time, in seconds, before expiring a mac_entry due to inactivity. */ -#define MAC_ENTRY_IDLE_TIME 300 +#define MAC_ENTRY_DEFAULT_IDLE_TIME 300 /* Time, in seconds, to lock an entry updated by a gratuitous ARP to avoid * relearning based on a reflection from a bond slave. */ @@ -50,7 +52,7 @@ struct mac_entry { } port; }; -int mac_entry_age(const struct mac_entry *); +int mac_entry_age(const struct mac_learning *, const struct mac_entry *); /* Returns true if mac_learning_insert() just created 'mac' and the caller has * not yet properly initialized it. */ @@ -80,10 +82,11 @@ struct mac_learning { front, most recently used at the back. */ uint32_t secret; /* Secret for randomizing hash table. */ unsigned long *flood_vlans; /* Bitmap of learning disabled VLANs. */ + unsigned int idle_time; /* Max age before deleting an entry. */ }; /* Basics. */ -struct mac_learning *mac_learning_create(void); +struct mac_learning *mac_learning_create(unsigned int idle_time); void mac_learning_destroy(struct mac_learning *); void mac_learning_run(struct mac_learning *, struct tag_set *); @@ -92,6 +95,7 @@ void mac_learning_wait(struct mac_learning *); /* Configuration. */ bool mac_learning_set_flood_vlans(struct mac_learning *, const unsigned long *bitmap); +void mac_learning_set_idle_time(struct mac_learning *, unsigned int idle_time); /* Learning. */ bool mac_learning_may_learn(const struct mac_learning *, diff --git a/ofproto/ofproto-dpif.c b/ofproto/ofproto-dpif.c index dee20076..28f04341 100644 --- a/ofproto/ofproto-dpif.c +++ b/ofproto/ofproto-dpif.c @@ -648,7 +648,7 @@ construct(struct ofproto *ofproto_) ofproto->sflow = NULL; ofproto->stp = NULL; hmap_init(&ofproto->bundles); - ofproto->ml = mac_learning_create(); + ofproto->ml = mac_learning_create(MAC_ENTRY_DEFAULT_IDLE_TIME); for (i = 0; i < MAX_MIRRORS; i++) { ofproto->mirrors[i] = NULL; } @@ -2150,6 +2150,13 @@ forward_bpdu_changed(struct ofproto *ofproto_) /* Revalidate cached flows whenever forward_bpdu option changes. */ ofproto->need_revalidate = true; } + +static void +set_mac_idle_time(struct ofproto *ofproto_, unsigned int idle_time) +{ + struct ofproto_dpif *ofproto = ofproto_dpif_cast(ofproto_); + mac_learning_set_idle_time(ofproto->ml, idle_time); +} /* Ports. */ @@ -5861,7 +5868,8 @@ ofproto_unixctl_fdb_show(struct unixctl_conn *conn, int argc OVS_UNUSED, struct ofbundle *bundle = e->port.p; ds_put_format(&ds, "%5d %4d "ETH_ADDR_FMT" %3d\n", ofbundle_get_a_port(bundle)->odp_port, - e->vlan, ETH_ADDR_ARGS(e->mac), mac_entry_age(e)); + e->vlan, ETH_ADDR_ARGS(e->mac), + mac_entry_age(ofproto->ml, e)); } unixctl_command_reply(conn, 200, ds_cstr(&ds)); ds_destroy(&ds); @@ -6350,5 +6358,6 @@ const struct ofproto_class ofproto_dpif_class = { set_flood_vlans, is_mirror_output_bundle, forward_bpdu_changed, + set_mac_idle_time, set_realdev, }; diff --git a/ofproto/ofproto-provider.h b/ofproto/ofproto-provider.h index 9e6b9ffd..cb97188a 100644 --- a/ofproto/ofproto-provider.h +++ b/ofproto/ofproto-provider.h @@ -1107,6 +1107,10 @@ struct ofproto_class { * will be invoked. */ void (*forward_bpdu_changed)(struct ofproto *ofproto); + /* Sets the MAC aging timeout for the OFPP_NORMAL action to 'idle_time', + * in seconds. */ + void (*set_mac_idle_time)(struct ofproto *ofproto, unsigned int idle_time); + /* Linux VLAN device support (e.g. "eth0.10" for VLAN 10.) * * This is deprecated. It is only for compatibility with broken device drivers diff --git a/ofproto/ofproto.c b/ofproto/ofproto.c index ca2032de..c35d4406 100644 --- a/ofproto/ofproto.c +++ b/ofproto/ofproto.c @@ -503,6 +503,16 @@ ofproto_set_forward_bpdu(struct ofproto *ofproto, bool forward_bpdu) } } +/* Sets the MAC aging timeout for the OFPP_NORMAL action on 'ofproto' to + * 'idle_time', in seconds. */ +void +ofproto_set_mac_idle_time(struct ofproto *ofproto, unsigned idle_time) +{ + if (ofproto->ofproto_class->set_mac_idle_time) { + ofproto->ofproto_class->set_mac_idle_time(ofproto, idle_time); + } +} + void ofproto_set_desc(struct ofproto *p, const char *mfr_desc, const char *hw_desc, diff --git a/ofproto/ofproto.h b/ofproto/ofproto.h index dd42ecf6..6aec062c 100644 --- a/ofproto/ofproto.h +++ b/ofproto/ofproto.h @@ -1,5 +1,5 @@ /* - * Copyright (c) 2009, 2010, 2011 Nicira Networks. + * Copyright (c) 2009, 2010, 2011, 2012 Nicira Networks. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. @@ -205,6 +205,7 @@ void ofproto_set_extra_in_band_remotes(struct ofproto *, void ofproto_set_in_band_queue(struct ofproto *, int queue_id); void ofproto_set_flow_eviction_threshold(struct ofproto *, unsigned threshold); void ofproto_set_forward_bpdu(struct ofproto *, bool forward_bpdu); +void ofproto_set_mac_idle_time(struct ofproto *, unsigned idle_time); void ofproto_set_desc(struct ofproto *, const char *mfr_desc, const char *hw_desc, const char *sw_desc, const char *serial_desc, diff --git a/vswitchd/bridge.c b/vswitchd/bridge.c index 869f73b7..3c1aecfa 100644 --- a/vswitchd/bridge.c +++ b/vswitchd/bridge.c @@ -32,6 +32,7 @@ #include "jsonrpc.h" #include "lacp.h" #include "list.h" +#include "mac-learning.h" #include "meta-flow.h" #include "netdev.h" #include "ofp-print.h" @@ -157,6 +158,7 @@ static void bridge_configure_datapath_id(struct bridge *); static void bridge_configure_flow_eviction_threshold(struct bridge *); static void bridge_configure_netflow(struct bridge *); static void bridge_configure_forward_bpdu(struct bridge *); +static void bridge_configure_mac_idle_time(struct bridge *); static void bridge_configure_sflow(struct bridge *, int *sflow_bridge_number); static void bridge_configure_stp(struct bridge *); static void bridge_configure_tables(struct bridge *); @@ -468,6 +470,7 @@ bridge_reconfigure(const struct ovsrec_open_vswitch *ovs_cfg) bridge_configure_mirrors(br); bridge_configure_flow_eviction_threshold(br); bridge_configure_forward_bpdu(br); + bridge_configure_mac_idle_time(br); bridge_configure_remotes(br, managers, n_managers); bridge_configure_netflow(br); bridge_configure_sflow(br, &sflow_bridge_number); @@ -1275,6 +1278,20 @@ bridge_configure_forward_bpdu(struct bridge *br) ofproto_set_forward_bpdu(br->ofproto, forward_bpdu); } +/* Set MAC aging time for 'br'. */ +static void +bridge_configure_mac_idle_time(struct bridge *br) +{ + const char *idle_time_str; + int idle_time; + + idle_time_str = bridge_get_other_config(br->cfg, "mac-aging-time"); + idle_time = (idle_time_str && atoi(idle_time_str) + ? atoi(idle_time_str) + : MAC_ENTRY_DEFAULT_IDLE_TIME); + ofproto_set_mac_idle_time(br->ofproto, idle_time); +} + static void bridge_pick_local_hw_addr(struct bridge *br, uint8_t ea[ETH_ADDR_LEN], struct iface **hw_addr_iface) diff --git a/vswitchd/vswitch.xml b/vswitchd/vswitch.xml index 25efdadf..fb9aa6d6 100644 --- a/vswitchd/vswitch.xml +++ b/vswitchd/vswitch.xml @@ -558,6 +558,26 @@ should be enabled. Default is disabled, set to true to enable. + + +

+ The maximum number of seconds to retain a MAC learning entry for + which no packets have been seen. The default is currently 300 + seconds (5 minutes). The value, if specified, is forced into a + reasonable range, currently 15 to 3600 seconds. +

+ +

+ A short MAC aging time allows a network to more quickly detect that a + host is no longer connected to a switch port. However, it also makes + it more likely that packets will be flooded unnecessarily, when they + are addressed to a connected host that rarely transmits packets. To + reduce the incidence of unnecessary flooding, use a MAC aging time + longer than the maximum interval at which a host will ordinarily + transmit packets. +

+ -- 2.30.2