| Message ID | 182d0b9c5460bc2a7b97c2bc3e3f74c14bd4fe4c.1726059087.git.echaudro@redhat.com |
|---|---|
| State | Accepted |
| Commit | ce789d991f748d95a34355e7813ddf18a64de504 |
| Delegated to: | Eelco Chaudron |
| Headers | show |
| Series | [ovs-dev,branch-2.17] ofproto-dpif-upcall: Avoid stale ukeys leaks. | expand |
| Context | Check | Description |
|---|---|---|
| ovsrobot/apply-robot | success | apply and check: success |
| ovsrobot/github-robot-_Build_and_Test | success | github build: passed |
Eelco Chaudron <echaudro@redhat.com> writes: > It is observed in some environments that there are much more ukeys than > actual DP flows. For example: > > $ ovs-appctl upcall/show > system@ovs-system: > flows : (current 7) (avg 6) (max 117) (limit 2125) > offloaded flows : 525 > dump duration : 1063ms > ufid enabled : true > > 23: (keys 3612) > 24: (keys 3625) > 25: (keys 3485) > > The revalidator threads are busy revalidating the stale ukeys leading to > high CPU and long dump duration. > > This patch tracks the number of consecutive missed dumps. If four dumps > are missed in a row, it is assumed that the datapath flow no longer > exists, and the ukey can be deleted. > > Reported-by: Roi Dayan <roid@nvidia.com> > Co-authored-by: Han Zhou <hzhou@ovn.org> > Co-authored-by: Roi Dayan <roid@nvidia.com> > Signed-off-by: Han Zhou <hzhou@ovn.org> > Signed-off-by: Roi Dayan <roid@nvidia.com> > Signed-off-by: Eelco Chaudron <echaudro@redhat.com> > > NOTE: Backported a portion of > 600125b2c380 ("ofproto: Add ofproto/detrace command to map UFIDs to OpenFlow.") > to provide `strip_dp_hash` macro. > --- Acked-by: Aaron Conole <aconole@redhat.com> Thanks for doing this backport, Eelco!
On Thu, Sep 12, 2024 at 05:13:56PM -0400, Aaron Conole wrote: > Eelco Chaudron <echaudro@redhat.com> writes: > > > It is observed in some environments that there are much more ukeys than > > actual DP flows. For example: > > > > $ ovs-appctl upcall/show > > system@ovs-system: > > flows : (current 7) (avg 6) (max 117) (limit 2125) > > offloaded flows : 525 > > dump duration : 1063ms > > ufid enabled : true > > > > 23: (keys 3612) > > 24: (keys 3625) > > 25: (keys 3485) > > > > The revalidator threads are busy revalidating the stale ukeys leading to > > high CPU and long dump duration. > > > > This patch tracks the number of consecutive missed dumps. If four dumps > > are missed in a row, it is assumed that the datapath flow no longer > > exists, and the ukey can be deleted. > > > > Reported-by: Roi Dayan <roid@nvidia.com> > > Co-authored-by: Han Zhou <hzhou@ovn.org> > > Co-authored-by: Roi Dayan <roid@nvidia.com> > > Signed-off-by: Han Zhou <hzhou@ovn.org> > > Signed-off-by: Roi Dayan <roid@nvidia.com> > > Signed-off-by: Eelco Chaudron <echaudro@redhat.com> > > > > NOTE: Backported a portion of > > 600125b2c380 ("ofproto: Add ofproto/detrace command to map UFIDs to OpenFlow.") > > to provide `strip_dp_hash` macro. > > --- > > Acked-by: Aaron Conole <aconole@redhat.com> > > > Thanks for doing this backport, Eelco! FTR, this was applied by Eelco to branch-2.17. - ofproto-dpif-upcall: Avoid stale ukeys leaks. https://github.com/openvswitch/ovs/commit/ce789d991f74
diff --git a/ofproto/ofproto-dpif-upcall.c b/ofproto/ofproto-dpif-upcall.c index 047f684e1..5c06beb16 100644 --- a/ofproto/ofproto-dpif-upcall.c +++ b/ofproto/ofproto-dpif-upcall.c @@ -55,6 +55,7 @@ COVERAGE_DEFINE(dumped_duplicate_flow); COVERAGE_DEFINE(dumped_new_flow); COVERAGE_DEFINE(handler_duplicate_upcall); COVERAGE_DEFINE(revalidate_missed_dp_flow); +COVERAGE_DEFINE(revalidate_missing_dp_flow); COVERAGE_DEFINE(ukey_dp_change); COVERAGE_DEFINE(ukey_invalid_stat_reset); COVERAGE_DEFINE(ukey_replace_contention); @@ -296,6 +297,7 @@ struct udpif_key { uint64_t dump_seq OVS_GUARDED; /* Tracks udpif->dump_seq. */ uint64_t reval_seq OVS_GUARDED; /* Tracks udpif->reval_seq. */ enum ukey_state state OVS_GUARDED; /* Tracks ukey lifetime. */ + uint32_t missed_dumps OVS_GUARDED; /* Missed consecutive dumps. */ /* 'state' debug information. */ unsigned int state_thread OVS_GUARDED; /* Thread that transitions. */ @@ -2924,6 +2926,20 @@ revalidator_sweep__(struct revalidator *revalidator, bool purge) result = revalidate_ukey(udpif, ukey, &stats, &odp_actions, reval_seq, &recircs); } + + if (ukey->dump_seq != dump_seq) { + ukey->missed_dumps++; + if (ukey->missed_dumps >= 4) { + /* If the flow was not dumped for 4 revalidator rounds, + * we can assume the datapath flow no longer exists + * and the ukey should be deleted. */ + COVERAGE_INC(revalidate_missing_dp_flow); + result = UKEY_DELETE; + } + } else { + ukey->missed_dumps = 0; + } + if (result != UKEY_KEEP) { /* Clears 'recircs' if filled by revalidate_ukey(). */ reval_op_init(&ops[n_ops++], result, udpif, ukey, &recircs, diff --git a/tests/ofproto-dpif.at b/tests/ofproto-dpif.at index 292e6e9b0..6423458d4 100644 --- a/tests/ofproto-dpif.at +++ b/tests/ofproto-dpif.at @@ -11933,3 +11933,48 @@ AT_CHECK([test 1 = `ovs-ofctl parse-pcap p2-tx.pcap | wc -l`]) OVS_VSWITCHD_STOP AT_CLEANUP + +AT_SETUP([ofproto-dpif - Cleanup missing datapath flows]) + +OVS_VSWITCHD_START +add_of_ports br0 1 2 + +m4_define([ICMP_PKT], [m4_join([,], + [eth(src=50:54:00:00:00:05,dst=50:54:00:00:00:07),eth_type(0x0800)], + [ipv4(src=10.10.10.2,dst=10.10.10.1,proto=1,tos=1,ttl=128,frag=no)], + [icmp(type=8,code=0)])]) + +AT_CHECK([ovs-ofctl del-flows br0]) +AT_CHECK([ovs-ofctl add-flow br0 'actions=normal' ]) + +AT_CHECK([ovs-appctl netdev-dummy/receive p1 'ICMP_PKT']) + +AT_CHECK([ovs-appctl dpctl/dump-flows --names | strip_used | strip_stats | dnl + strip_duration | strip_dp_hash | sort], [0], [dnl +flow-dump from the main thread: +recirc_id(0),in_port(p1),packet_type(ns=0,id=0),eth(src=50:54:00:00:00:05,dst=50:54:00:00:00:07),eth_type(0x0800),ipv4(frag=no), packets:0, bytes:0, used:never, actions:br0,p2 +]) + +dnl Make sure the ukey exists. +AT_CHECK([ovs-appctl upcall/show | grep '(keys' | awk '{print $3}' | \ + grep -q '1)'], [0]) + +dnl Delete all datapath flows, and make sure they are gone. +AT_CHECK([ovs-appctl dpctl/del-flows]) +AT_CHECK([ovs-appctl dpctl/dump-flows --names ], [0], []) + +dnl Move forward in time and make sure we have at least 4 * 500ms. +AT_CHECK([ovs-appctl time/warp 3000 300], [0], [ignore]) + +dnl Make sure no more ukeys exists. +AT_CHECK([ovs-appctl upcall/show | grep '(keys' | awk '{print $3}' | \ + grep -qv '0)'], [1]) + +dnl Verify coverage counter was hit. +AT_CHECK([ovs-appctl coverage/read-counter revalidate_missing_dp_flow], [0], + [dnl +1 +]) + +OVS_VSWITCHD_STOP(["/failed to flow_del (No such file or directory)/d"]) +AT_CLEANUP diff --git a/tests/ofproto-macros.at b/tests/ofproto-macros.at index 9e32f53c0..00dbd07d8 100644 --- a/tests/ofproto-macros.at +++ b/tests/ofproto-macros.at @@ -164,6 +164,11 @@ strip_recirc() { s/recirc_id=[[x0-9]]*/recirc_id=<recirc>/ s/recirc([[x0-9]]*)/recirc(<recirc>)/' } + +# Strips dp_hash from output. +strip_dp_hash() { + sed 's/dp_hash([[0-9a-fx/]]*),//' +} m4_divert_pop([PREPARE_TESTS]) m4_define([TESTABLE_LOG], [-vPATTERN:ANY:'%c|%p|%m'])