sorry, the last email does not quote the full information. by choosing the second solution, I mean
" the delete error case: EVICTING -> EVICTED Change both to INCONSISTENT: the modify error case: did not change. the delete error case: EVICTING -> INCONSISTENT -> EVICTED? this will make the state machine allows both INCONSISTENT -> EVICTING and EVICTING -> INCONSISTENT transitions. which I guess it's more confusing ... Another solution is that, drop INCONSISTENT state, if modify fails, just changes to EVICTING. and let the revalidate or sweep to take care of EVICTING state ukey and initial another dp_ops to remove it. ” so, we choose to not to use INCONSISTENT. Peng He <[email protected]> 于2022年12月10日周六 08:37写道： > Patch v5 has statistics issues. > > In order to solve this issue, we had a discussion. > > below is the quote of the email. > > ” > After a second thought, I think maybe keeping INCONSISTENT just for the > modify error is a better option. > > With current patch: > 1. > the modify error case: > OPERATIONAL -> INCONSISTENT -> EVICTING -> EVICTED > 2. > the delete error case: > EVICTING -> EVICTED > > Change both to INCONSISTENT: > > the modify error case: > did not change. > > the delete error case: > EVICTING -> INCONSISTENT -> EVICTED? > > “ > > And we agree to take the second solution. > > > > Eelco Chaudron <[email protected]> 于2022年12月8日周四 18:54写道： > >> >> >> On 27 Nov 2022, at 8:28, Peng He wrote: >> >> > push_dp_ops only handles delete ops errors but ignores the modify >> > ops results. It's better to handle all the dp operation errors in >> > a consistent way. >> > >> > We observe in the production environment that sometimes a megaflow >> > with wrong actions keep staying in datapath. The coverage command shows >> > revalidators have dumped several times, however the correct >> > actions are not set. This implies that the ukey's action does not >> > equal to the meagaflow's, i.e. revalidators think the underlying >> > megaflow's actions are correct however they are not. >> > >> > We also check the megaflow using the ofproto/trace command, and the >> > actions are not matched with the ones in the actual magaflow. By >> > performing a revalidator/purge command, the right actions are set. >> > >> > This patch prevents the inconsistency by considering modify failure >> > in revalidators. >> > >> > To note, we cannot perform two state transitions and change ukey_state >> > into UKEY_EVICTED directly here, because, if we do so, the >> > sweep will remove the ukey alone and leave dp flow alive. Later, the >> > dump will retrieve the dp flow and might even recover it. This will >> > contribute the stats of this dp flow twice. >> > >> > Signed-off-by: Peng He <[email protected]> >> > --- >> > ofproto/ofproto-dpif-upcall.c | 34 +++++++++++++++++++++++----------- >> > 1 file changed, 23 insertions(+), 11 deletions(-) >> > >> > diff --git a/ofproto/ofproto-dpif-upcall.c >> b/ofproto/ofproto-dpif-upcall.c >> > index 7ad728adf..c2cefbeb8 100644 >> > --- a/ofproto/ofproto-dpif-upcall.c >> > +++ b/ofproto/ofproto-dpif-upcall.c >> > @@ -2416,26 +2416,30 @@ push_dp_ops(struct udpif *udpif, struct ukey_op >> *ops, size_t n_ops) >> > >> > for (i = 0; i < n_ops; i++) { >> > struct ukey_op *op = &ops[i]; >> > - struct dpif_flow_stats *push, *stats, push_buf; >> > - >> > - stats = op->dop.flow_del.stats; >> > - push = &push_buf; >> > - >> > - if (op->dop.type != DPIF_OP_FLOW_DEL) { >> > - /* Only deleted flows need their stats pushed. */ >> > - continue; >> > - } >> > >> > if (op->dop.error) { >> > - /* flow_del error, 'stats' is unusable. */ >> > if (op->ukey) { >> > ovs_mutex_lock(&op->ukey->mutex); >> > - transition_ukey(op->ukey, UKEY_EVICTED); >> > + if (op->dop.type == DPIF_OP_FLOW_DEL) { >> > + transition_ukey(op->ukey, UKEY_EVICTED); >> > + } else { >> > + transition_ukey(op->ukey, UKEY_EVICTING); >> > + } >> > ovs_mutex_unlock(&op->ukey->mutex); >> > } >> > continue; >> > } >> > >> > + if (op->dop.type != DPIF_OP_FLOW_DEL) { >> > + /* Only deleted flows need their stats pushed. */ >> > + continue; >> > + } >> > + >> > + struct dpif_flow_stats *push, *stats, push_buf; >> > + >> > + stats = op->dop.flow_del.stats; >> > + push = &push_buf; >> > + >> > if (op->ukey) { >> > ovs_mutex_lock(&op->ukey->mutex); >> > transition_ukey(op->ukey, UKEY_EVICTED); >> > @@ -2848,6 +2852,14 @@ revalidator_sweep__(struct revalidator >> *revalidator, bool purge) >> > continue; >> > } >> > ukey_state = ukey->state; >> > + >> > + if (ukey_state == UKEY_EVICTING) { >> > + /* previous modify operation fails on this ukey and >> ukey_state >> > + * is set to UKEY_EVICTING, issue a delete operation >> on this >> > + * ukey. >> > + */ >> > + delete_op_init(udpif, &ops[n_ops++], ukey); >> >> How can we be sure this state here is only for failing to modify >> operations? >> This state is set in other places in the code also. >> > > because revalidate_sweep is called after revaldiate. all the datapath ops > have already been > pushed, and if there are ukeys at UKEY_EVICTING, it's because previously > datapath ops > have errors. and if del ops fail, ukey is deleted. so only ukeys at > UKEY_EVICTING must > come from modify fail. > > >> Maybe we should keep the INCONSISTENT state to avoid this (see v5)? >> >> > + } >> > if (ukey_state == UKEY_OPERATIONAL >> > || (ukey_state == UKEY_VISIBLE && purge)) { >> > struct recirc_refs recircs = >> RECIRC_REFS_EMPTY_INITIALIZER; >> > -- >> > 2.25.1 >> >> > > -- > hepeng > -- hepeng _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
