When the a revalidator thread is updating statistics for an XC_LEARN xcache entry in xlate_push_stats_entry it uses ofproto_flow_mod_learn. The revalidator will update stats for rules even if they are in a removed state or marked as invisible. However, ofproto_flow_mod_learn will detect if a flow has been removed and re-add it in that case. This can result in an old learn action replacing the new learn action that had replaced it in the first place.
This change adds a new last_used parameter to ofproto_flow_mod_learn allowing the caller to provide a timestamp that will be fed into the learned rule's modified time. The provided timestamp should be the time of the last packet activity. If last_used is not set then the current time is used, as is the current behaviour. This change also adds a check when replacing a learned rule to favour the newest rule. Reported-at: https://bugzilla.redhat.com/show_bug.cgi?id=2213892 Signed-off-by: Mike Pattrick <[email protected]> --- v2: Added additional checks if rule is removed v3: v2 patch was corrupted in transit v4: Added check against dpif flow stats v5: Fixed typos, updated commit message Changed timestamps to use datapath timestamp more consistently v6: Added a unit test, changed some variable names and comments, zero is no longer an acceptable value v7: Simplified unit test, updated comments. --- ofproto/ofproto-dpif-xlate-cache.c | 2 +- ofproto/ofproto-dpif-xlate.c | 10 ++- ofproto/ofproto-dpif.c | 2 +- ofproto/ofproto-provider.h | 6 +- ofproto/ofproto.c | 60 +++++++++++-- tests/learn.at | 132 +++++++++++++++++++++++++++++ 6 files changed, 198 insertions(+), 14 deletions(-) diff --git a/ofproto/ofproto-dpif-xlate-cache.c b/ofproto/ofproto-dpif-xlate-cache.c index 9224ee2e6..2e1fcb3a6 100644 --- a/ofproto/ofproto-dpif-xlate-cache.c +++ b/ofproto/ofproto-dpif-xlate-cache.c @@ -125,7 +125,7 @@ xlate_push_stats_entry(struct xc_entry *entry, case XC_LEARN: { enum ofperr error; error = ofproto_flow_mod_learn(entry->learn.ofm, true, - entry->learn.limit, NULL); + entry->learn.limit, NULL, stats->used); if (error) { static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5); VLOG_WARN_RL(&rl, "xcache LEARN action execution failed."); diff --git a/ofproto/ofproto-dpif-xlate.c b/ofproto/ofproto-dpif-xlate.c index 47ea0f47e..d608a5f25 100644 --- a/ofproto/ofproto-dpif-xlate.c +++ b/ofproto/ofproto-dpif-xlate.c @@ -5700,8 +5700,16 @@ xlate_learn_action(struct xlate_ctx *ctx, const struct ofpact_learn *learn) if (!error) { bool success = true; if (ctx->xin->allow_side_effects) { + long long int last_used; + + if (ctx->xin->resubmit_stats) { + last_used = ctx->xin->resubmit_stats->used; + } else { + last_used = time_msec(); + } error = ofproto_flow_mod_learn(ofm, ctx->xin->xcache != NULL, - learn->limit, &success); + learn->limit, &success, + last_used); } else if (learn->limit) { if (!ofm->temp_rule || ofm->temp_rule->state != RULE_INSERTED) { diff --git a/ofproto/ofproto-dpif.c b/ofproto/ofproto-dpif.c index e22ca757a..ba5706f6a 100644 --- a/ofproto/ofproto-dpif.c +++ b/ofproto/ofproto-dpif.c @@ -4880,7 +4880,7 @@ packet_xlate(struct ofproto *ofproto_, struct ofproto_packet_out *opo) if (entry->type == XC_LEARN) { struct ofproto_flow_mod *ofm = entry->learn.ofm; - error = ofproto_flow_mod_learn_refresh(ofm); + error = ofproto_flow_mod_learn_refresh(ofm, time_msec()); if (error) { goto error_out; } diff --git a/ofproto/ofproto-provider.h b/ofproto/ofproto-provider.h index 143ded690..9f7b8b6e8 100644 --- a/ofproto/ofproto-provider.h +++ b/ofproto/ofproto-provider.h @@ -2027,9 +2027,11 @@ enum ofperr ofproto_flow_mod_init_for_learn(struct ofproto *, struct ofproto_flow_mod *) OVS_EXCLUDED(ofproto_mutex); enum ofperr ofproto_flow_mod_learn(struct ofproto_flow_mod *, bool keep_ref, - unsigned limit, bool *below_limit) + unsigned limit, bool *below_limit, + long long int last_used) OVS_EXCLUDED(ofproto_mutex); -enum ofperr ofproto_flow_mod_learn_refresh(struct ofproto_flow_mod *ofm); +enum ofperr ofproto_flow_mod_learn_refresh(struct ofproto_flow_mod *ofm, + long long int last_used); enum ofperr ofproto_flow_mod_learn_start(struct ofproto_flow_mod *ofm) OVS_REQUIRES(ofproto_mutex); void ofproto_flow_mod_learn_revert(struct ofproto_flow_mod *ofm) diff --git a/ofproto/ofproto.c b/ofproto/ofproto.c index dbf4958bc..7d3b3b6d1 100644 --- a/ofproto/ofproto.c +++ b/ofproto/ofproto.c @@ -5472,7 +5472,8 @@ ofproto_flow_mod_init_for_learn(struct ofproto *ofproto, } enum ofperr -ofproto_flow_mod_learn_refresh(struct ofproto_flow_mod *ofm) +ofproto_flow_mod_learn_refresh(struct ofproto_flow_mod *ofm, + long long int last_used) { enum ofperr error = 0; @@ -5493,9 +5494,37 @@ ofproto_flow_mod_learn_refresh(struct ofproto_flow_mod *ofm) * this function is executed the rule will be reinstated. */ if (rule->state == RULE_REMOVED) { struct cls_rule cr; + struct oftable *table = &rule->ofproto->tables[rule->table_id]; + ovs_version_t tables_version = rule->ofproto->tables_version; + + if (!cls_rule_visible_in_version(&rule->cr, tables_version)) { + const struct cls_rule *curr_cls_rule; + + /* Only check for matching classifier rules and their modified + * time, instead of also checking all rule metadata, with the goal + * of suprressing a learn action update that would replace a more + * recent rule in the classifier. */ + curr_cls_rule = classifier_find_rule_exactly(&table->cls, + &rule->cr, + tables_version); + if (curr_cls_rule) { + struct rule *curr_rule = rule_from_cls_rule(curr_cls_rule); + long long int curr_last_used; + + ovs_mutex_lock(&curr_rule->mutex); + curr_last_used = curr_rule->modified; + ovs_mutex_unlock(&curr_rule->mutex); + + if (curr_last_used > last_used) { + /* In the case of a newer visible rule, don't recreate the + * current rule. */ + return 0; + } + } + } - cls_rule_clone(&cr, &rule->cr); ovs_mutex_lock(&rule->mutex); + cls_rule_clone(&cr, &rule->cr); error = ofproto_rule_create(rule->ofproto, &cr, rule->table_id, rule->flow_cookie, rule->idle_timeout, @@ -5506,6 +5535,7 @@ ofproto_flow_mod_learn_refresh(struct ofproto_flow_mod *ofm) rule->match_tlv_bitmap, rule->ofpacts_tlv_bitmap, &ofm->temp_rule); + ofm->temp_rule->modified = last_used; ovs_mutex_unlock(&rule->mutex); if (!error) { ofproto_rule_unref(rule); /* Release old reference. */ @@ -5513,7 +5543,7 @@ ofproto_flow_mod_learn_refresh(struct ofproto_flow_mod *ofm) } else { /* Refresh the existing rule. */ ovs_mutex_lock(&rule->mutex); - rule->modified = time_msec(); + rule->modified = last_used; ovs_mutex_unlock(&rule->mutex); } return error; @@ -5565,10 +5595,16 @@ ofproto_flow_mod_learn_finish(struct ofproto_flow_mod *ofm, /* Refresh 'ofm->temp_rule', for which the caller holds a reference, if already * in the classifier, insert it otherwise. If the rule has already been - * removed from the classifier, a new rule is created using 'ofm->temp_rule' as - * a template and the reference to the old 'ofm->temp_rule' is freed. If - * 'keep_ref' is true, then a reference to the current rule is held, otherwise - * it is released and 'ofm->temp_rule' is set to NULL. + * removed from the classifier and replaced by another rule, the 'last_used' + * parameter is used to determine whether the newer rule is replaced or kept. + * If 'last_used' is greater than the last modified time of an identical rule + * in the classifier, then a new rule is created using 'ofm->temp_rule' as a + * template and the reference to the old 'ofm->temp_rule' is freed. If the + * rule has been removed but another identical rule doesn't exist in the + * classifier, then it will be recreated. If the rule hasn't been removed + * from the classifier, then 'last_used' is used to update the rules modified + * time. If 'keep_ref' is true, then a reference to the current rule is held, + * otherwise it is released and 'ofm->temp_rule' is set to NULL. * * If 'limit' != 0, insertion will fail if there are more than 'limit' rules * in the same table with the same cookie. If insertion succeeds, @@ -5579,10 +5615,11 @@ ofproto_flow_mod_learn_finish(struct ofproto_flow_mod *ofm, * during the call. */ enum ofperr ofproto_flow_mod_learn(struct ofproto_flow_mod *ofm, bool keep_ref, - unsigned limit, bool *below_limitp) + unsigned limit, bool *below_limitp, + long long int last_used) OVS_EXCLUDED(ofproto_mutex) { - enum ofperr error = ofproto_flow_mod_learn_refresh(ofm); + enum ofperr error = ofproto_flow_mod_learn_refresh(ofm, last_used); struct rule *rule = ofm->temp_rule; bool below_limit = true; @@ -5615,6 +5652,11 @@ ofproto_flow_mod_learn(struct ofproto_flow_mod *ofm, bool keep_ref, error = ofproto_flow_mod_learn_start(ofm); if (!error) { + /* ofproto_flow_mod_learn_start may have overwritten + * modified with current time. */ + ovs_mutex_lock(&ofm->temp_rule->mutex); + ofm->temp_rule->modified = last_used; + ovs_mutex_unlock(&ofm->temp_rule->mutex); error = ofproto_flow_mod_learn_finish(ofm, NULL); } } else { diff --git a/tests/learn.at b/tests/learn.at index d127fed34..8e5054c08 100644 --- a/tests/learn.at +++ b/tests/learn.at @@ -836,3 +836,135 @@ AT_CHECK([ovs-vsctl add-br br1 -- set b br1 datapath_type=dummy]) OVS_VSWITCHD_STOP AT_CLEANUP + +AT_SETUP([learning action - flapping learn rule]) +OVS_VSWITCHD_START +add_of_ports br0 1 2 3 + +ovs-appctl time/stop +AT_CHECK([[ovs-ofctl add-flow br0 'table=0,priority=2,in_port=1,actions=resubmit(,2)']]) +AT_CHECK([[ovs-ofctl add-flow br0 'table=0,priority=2,in_port=3,actions=resubmit(,2)']]) +AT_CHECK([[ovs-ofctl add-flow br0 'table=0,in_port=2,actions=normal']]) +AT_CHECK([[ovs-ofctl add-flow br0 'table=0,priority=4,actions=drop']]) +AT_CHECK([[ovs-ofctl add-flow br0 'table=2,actions=learn(table=0,hard_timeout=3,priority=1,cookie=0x0001020304050607,NXM_OF_ETH_DST[]=NXM_OF_ETH_SRC[],output:OXM_OF_IN_PORT[]),output:2']]) + +packet1='in_port(1),eth(src=50:54:00:00:00:06,dst=50:54:00:00:00:07),eth_type(0x0800),ipv4(src=192.168.0.1,dst=192.168.0.2,proto=6,tos=0,ttl=64,frag=no),tcp(src=8,dst=9)' +packet2='in_port(3),eth(src=50:54:00:00:00:06,dst=50:54:00:00:00:07),eth_type(0x0800),ipv4(src=192.168.0.1,dst=192.168.0.2,proto=6,tos=0,ttl=64,frag=no),tcp(src=8,dst=9)' + +ovs-appctl revalidator/pause +ovs-appctl netdev-dummy/receive p3 $packet2 +ovs-appctl time/warp 75 +ovs-appctl netdev-dummy/receive p1 $packet1 +ovs-appctl time/warp 75 +ovs-appctl netdev-dummy/receive p3 $packet2 +ovs-appctl time/warp 75 +ovs-appctl netdev-dummy/receive p1 $packet1 +ovs-appctl time/warp 75 +ovs-appctl revalidator/resume +ovs-appctl revalidator/wait + +AT_CHECK([ovs-ofctl --no-stats dump-flows br0 | ofctl_strip | sed -e 's/n_packets=[[0-9]]*, n_bytes=[[0-9]]*, //' | sort], [0], [dnl + cookie=0x1020304050607, hard_timeout=3, priority=1,vlan_tci=0x0000/0x0fff,dl_dst=50:54:00:00:00:06 actions=output:1 + in_port=2 actions=NORMAL + priority=2 actions=drop + priority=2,in_port=1 actions=resubmit(,2) + priority=2,in_port=3 actions=resubmit(,2) + table=2, actions=learn(table=0,hard_timeout=3,priority=1,cookie=0x1020304050607,NXM_OF_ETH_DST[[]]=NXM_OF_ETH_SRC[[]],output:OXM_OF_IN_PORT[[]]),output:2 +NXST_FLOW reply: +]) + +ovs-appctl revalidator/pause +ovs-appctl netdev-dummy/receive p1 $packet1 +ovs-appctl time/warp 75 +ovs-appctl netdev-dummy/receive p3 $packet2 +ovs-appctl time/warp 75 +ovs-appctl netdev-dummy/receive p1 $packet1 +ovs-appctl time/warp 75 +ovs-appctl netdev-dummy/receive p3 $packet2 +ovs-appctl time/warp 75 + +ovs-appctl revalidator/resume +ovs-appctl revalidator/wait + +AT_CHECK([ovs-ofctl --no-stats dump-flows br0 | ofctl_strip | sort], [0], [dnl + cookie=0x1020304050607, hard_timeout=3, priority=1,vlan_tci=0x0000/0x0fff,dl_dst=50:54:00:00:00:06 actions=output:3 + in_port=2 actions=NORMAL + priority=2 actions=drop + priority=2,in_port=1 actions=resubmit(,2) + priority=2,in_port=3 actions=resubmit(,2) + table=2, actions=learn(table=0,hard_timeout=3,priority=1,cookie=0x1020304050607,NXM_OF_ETH_DST[[]]=NXM_OF_ETH_SRC[[]],output:OXM_OF_IN_PORT[[]]),output:2 +NXST_FLOW reply: +]) + +ovs-appctl time/warp 1000 3001 + +AT_CHECK([ovs-ofctl dump-flows br0 | ofctl_strip | sort], [0], [dnl + in_port=2 actions=NORMAL + priority=2 actions=drop + priority=2,in_port=1 actions=resubmit(,2) + priority=2,in_port=3 actions=resubmit(,2) + table=2, actions=learn(table=0,hard_timeout=3,priority=1,cookie=0x1020304050607,NXM_OF_ETH_DST[[]]=NXM_OF_ETH_SRC[[]],output:OXM_OF_IN_PORT[[]]),output:2 +NXST_FLOW reply: +]) + +OVS_VSWITCHD_STOP +AT_CLEANUP + +AT_SETUP([learning action - flapping learn rule]) +OVS_VSWITCHD_START +add_of_ports br0 1 2 3 + +ovs-appctl time/stop +AT_CHECK([[ovs-ofctl add-flow br0 'table=0,priority=2,in_port=1,actions=resubmit(,2)']]) +AT_CHECK([[ovs-ofctl add-flow br0 'table=0,priority=2,in_port=2,actions=resubmit(,2)']]) +AT_CHECK([[ovs-ofctl add-flow br0 'table=2,actions=learn(table=0,hard_timeout=3,priority=1,cookie=0x123,NXM_OF_ETH_DST[]=NXM_OF_ETH_SRC[],output:OXM_OF_IN_PORT[]),output:3']]) + +packet1='eth(src=50:54:00:00:00:06,dst=50:54:00:00:00:07),eth_type(0x0800),ipv4(src=192.168.0.1,dst=192.168.0.2,proto=6,tos=0,ttl=64,frag=no),tcp(src=8,dst=9)' +packet2='eth(src=50:54:00:00:00:06,dst=50:54:00:00:00:07),eth_type(0x0800),ipv4(src=192.168.0.1,dst=192.168.0.2,proto=6,tos=0,ttl=64,frag=no),tcp(src=8,dst=9)' + +ovs-appctl revalidator/pause +ovs-appctl netdev-dummy/receive p2 $packet2 +ovs-appctl time/warp 75 +ovs-appctl netdev-dummy/receive p1 $packet1 +ovs-appctl time/warp 75 +ovs-appctl netdev-dummy/receive p2 $packet2 +ovs-appctl time/warp 75 +ovs-appctl netdev-dummy/receive p1 $packet1 +ovs-appctl time/warp 75 +ovs-appctl revalidator/resume +ovs-appctl revalidator/wait + +ovs-ofctl --no-stats dump-flows br0 + +AT_CHECK([ovs-ofctl --no-stats dump-flows br0 | ofctl_strip | sort | grep 0x123], [0], [dnl + cookie=0x123, hard_timeout=3, priority=1,dl_dst=50:54:00:00:00:06 actions=output:1 + table=2, actions=learn(table=0,hard_timeout=3,priority=1,cookie=0x123,NXM_OF_ETH_DST[[]]=NXM_OF_ETH_SRC[[]],output:OXM_OF_IN_PORT[[]]),output:3 +]) + +ovs-appctl revalidator/pause +ovs-appctl netdev-dummy/receive p1 $packet1 +ovs-appctl time/warp 75 +ovs-appctl netdev-dummy/receive p2 $packet2 +ovs-appctl time/warp 75 +ovs-appctl netdev-dummy/receive p1 $packet1 +ovs-appctl time/warp 75 +ovs-appctl netdev-dummy/receive p2 $packet2 +ovs-appctl time/warp 75 + +ovs-appctl revalidator/resume +ovs-appctl revalidator/wait + +AT_CHECK([ovs-ofctl --no-stats dump-flows br0 | ofctl_strip | sort | grep 0x123], [0], [dnl + cookie=0x123, hard_timeout=3, priority=1,dl_dst=50:54:00:00:00:06 actions=output:2 + table=2, actions=learn(table=0,hard_timeout=3,priority=1,cookie=0x123,NXM_OF_ETH_DST[[]]=NXM_OF_ETH_SRC[[]],output:OXM_OF_IN_PORT[[]]),output:3 +]) + +dnl Wait and check for learned rule eviction +ovs-appctl time/warp 3200 + +AT_CHECK([ovs-ofctl --no-stats dump-flows br0 | ofctl_strip | grep 0x123], [0], [dnl + table=2, actions=learn(table=0,hard_timeout=3,priority=1,cookie=0x123,NXM_OF_ETH_DST[[]]=NXM_OF_ETH_SRC[[]],output:OXM_OF_IN_PORT[[]]),output:3 +]) + +OVS_VSWITCHD_STOP +AT_CLEANUP -- 2.39.3 _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
