[ovs-dev] [PATCH ovn v7 5/9] ovn-controller: I-P for ct zone and OVS interface changes in flow output stage.
Han Zhou
hzhou at ovn.org
Sat May 23 01:59:53 UTC 2020
On Fri, May 22, 2020 at 10:29 AM Numan Siddique <numans at ovn.org> wrote:
>
>
>
> On Thu, May 21, 2020 at 12:02 PM Han Zhou <hzhou at ovn.org> wrote:
>>
>> On Wed, May 20, 2020 at 12:41 PM <numans at ovn.org> wrote:
>> >
>> > From: Numan Siddique <numans at ovn.org>
>> >
>> > This patch handles ct zone changes and OVS interface changes
incrementally
>> > in the flow output stage.
>> >
>> > Any changes to ct zone can be handled by running physical_run() instead
>> of running
>> > flow_output_run(). And any changes to OVS interfaces can be either
handled
>> > incrementally (for OVS interfaces representing VIFs) or just running
>> > physical_run() (for tunnel and other types of interfaces).
>> >
>> > To better handle this, a new engine node 'physical_flow_changes' is
added
>> which
>> > handles changes to ct zone and OVS interfaces.
>> >
>> Hi Numan,
>>
> Hi Han,
>
> Thanks for the review and comments. Please see below.
>
>
>>
>> The engine node physical_flow_changes looks weird because it doesn't
really
>> have any data but merely to trigger some compute when VIF changes.
>> I think it can be handled in a more straightforward way. In fact there
was
>> a miss in my initial I-P patch that there are still global variables used
>> in physical.c (my bad):
>> - localvif_to_ofport
>> - tunnels
>> In the principle of I-P engine global variable shouldn't be used because
>> otherwise there is no way to ensure the dependency graph is followed. The
>> current I-P is sitll correct only because interface changes (which in
turn
>> causes the above global var changes) always triggers recompute.
>>
>> Now to handle interface changes incrementally, we should simply move
these
>> global vars to engine nodes, and add them as input for flow_output, and
>> also their input will be OVS_Interface (and probably some other inputs).
>> With this, the dependency graph would be clear and implementation of each
>> input handler will be straightforward. Otherwise, it would be really hard
>> to follow the logic and deduce the correctness for all corner cases,
>> although it may be correct for normal scenarios that I believe you have
>> done thorough tests. Do you mind refactoring it?
>
>
> Right now, the flow_output node has an "en_ct_zones" engine as input and
it doesn't have
> OVS_interface as input. But this is ok as any runtime data change will
trigger recomputing.
>
Do you mean OVS_interface should actually be input of "en_ct_zones", but it
is ok to not add it? But I don't understand why should it be input of
en_ct_zones. Maybe I missed something?
My point above is about the dependency between flow_output and
OVS_interface. flow_output actually depends on OVS_interface. The two
global variables allowed flow_output to use OVS_interface data without the
dependancy in the graph. Now since we incrementally procssing OVS_interface
changes, we'd better fix the dependency graph to ensure the correctness. I
had encounted very tricky bugs even when some very trivial part of the I-P
engine rule was not followed, and finally found out defining the engine
node properly was the easiest fix.
> If en_ct_zones engine node changes, there is no need to trigger full
recompute and we
> call "physical_run()", it should be enough. Although we can definitely
further improve it
> and this can be tackled separately.
>
> In my understanding, I think we can also handle ovs interface changes
incrementally and if we can't
> we can just call "physical_run()" instead of full flow recompute.
>
> With this patch, it adds an engine node for physical flow changes and the
input for that is en_ct_zone
> and ovs interface. I understand and agree that it's a bit weird.
>
> How to handle it when both
> - en_ct_zone changes
> - some ovs interface changes.
>
> If both these inputs are direct inputs to the flow_output engine, then we
may end up calling "physical_run()"
> twice. And I wanted to avoid that and hence added a physical_flow_changes
node as an intermediate.
> How do you suggest we handle this if we directly handle the ovs interface
changes in flow_output engine ?
>
Not sure if I understand completely, but it seems you are suggesting we can
afford a recompute for physical flows, but not for logical flows, and in
some cases this can happen. Hoewver, you are trying to make a full phyical
computing appear as incremental processing, but you are not happy with this
kind of I-P because the cost is high, so you want to avoid calling it
multiple times, so a intermediate node is added for that purpose.
If this is the case, I'd suggest to handle it more cleanly with the I-P
engine. We can split the flow_output into separate nodes: logical_output
and physical_output, and add a dependency (fake) from physical_output to
logical_output just to make sure physical_output is the last node to
compute, so that even if it is recomputed it doesn't matter that much. Now
we call physical_run only in recompute of physical_output node, and since
it is recompute, it won't be called multiple times. What do you think?
> Thanks
> Numan
>
>
>>
>>
>> In addition, please see another comment inlined.
>>
>> Thanks,
>> Han
>>
>>
>> > Acked-by: Mark Michelson <mmichels at redhat.com>
>> > Signed-off-by: Numan Siddique <numans at ovn.org>
>> > ---
>> > controller/binding.c | 23 +----------
>> > controller/binding.h | 24 ++++++++++-
>> > controller/ovn-controller.c | 82 ++++++++++++++++++++++++++++++++++++-
>> > controller/physical.c | 51 +++++++++++++++++++++++
>> > controller/physical.h | 5 ++-
>> > 5 files changed, 159 insertions(+), 26 deletions(-)
>> >
>> > diff --git a/controller/binding.c b/controller/binding.c
>> > index d5e8e4773..f00c975ce 100644
>> > --- a/controller/binding.c
>> > +++ b/controller/binding.c
>> > @@ -504,7 +504,7 @@ remove_local_lport_ids(const struct
>> sbrec_port_binding *binding_rec,
>> > * 'struct local_binding' is used. A shash of these local bindings is
>> > * maintained with the 'external_ids:iface-id' as the key to the
shash.
>> > *
>> > - * struct local_binding has 3 main fields:
>> > + * struct local_binding (defined in binding.h) has 3 main fields:
>> > * - type
>> > * - OVS interface row object
>> > * - Port_Binding row object
>> > @@ -540,21 +540,6 @@ remove_local_lport_ids(const struct
>> sbrec_port_binding *binding_rec,
>> > * when it sees the ARP packet from the parent's VIF.
>> > *
>> > */
>> > -enum local_binding_type {
>> > - BT_VIF,
>> > - BT_CONTAINER,
>> > - BT_VIRTUAL
>> > -};
>> > -
>> > -struct local_binding {
>> > - char *name;
>> > - enum local_binding_type type;
>> > - const struct ovsrec_interface *iface;
>> > - const struct sbrec_port_binding *pb;
>> > -
>> > - /* shash of 'struct local_binding' representing children. */
>> > - struct shash children;
>> > -};
>> >
>> > static struct local_binding *
>> > local_binding_create(const char *name, const struct ovsrec_interface
>> *iface,
>> > @@ -576,12 +561,6 @@ local_binding_add(struct shash *local_bindings,
>> struct local_binding *lbinding)
>> > shash_add(local_bindings, lbinding->name, lbinding);
>> > }
>> >
>> > -static struct local_binding *
>> > -local_binding_find(struct shash *local_bindings, const char *name)
>> > -{
>> > - return shash_find_data(local_bindings, name);
>> > -}
>> > -
>> > static void
>> > local_binding_destroy(struct local_binding *lbinding)
>> > {
>> > diff --git a/controller/binding.h b/controller/binding.h
>> > index f7ace6faf..21118ecd4 100644
>> > --- a/controller/binding.h
>> > +++ b/controller/binding.h
>> > @@ -18,6 +18,7 @@
>> > #define OVN_BINDING_H 1
>> >
>> > #include <stdbool.h>
>> > +#include "openvswitch/shash.h"
>> >
>> > struct hmap;
>> > struct ovsdb_idl;
>> > @@ -32,7 +33,6 @@ struct sbrec_chassis;
>> > struct sbrec_port_binding_table;
>> > struct sset;
>> > struct sbrec_port_binding;
>> > -struct shash;
>> >
>> > struct binding_ctx_in {
>> > struct ovsdb_idl_txn *ovnsb_idl_txn;
>> > @@ -60,6 +60,28 @@ struct binding_ctx_out {
>> > struct smap *local_iface_ids;
>> > };
>> >
>> > +enum local_binding_type {
>> > + BT_VIF,
>> > + BT_CONTAINER,
>> > + BT_VIRTUAL
>> > +};
>> > +
>> > +struct local_binding {
>> > + char *name;
>> > + enum local_binding_type type;
>> > + const struct ovsrec_interface *iface;
>> > + const struct sbrec_port_binding *pb;
>> > +
>> > + /* shash of 'struct local_binding' representing children. */
>> > + struct shash children;
>> > +};
>> > +
>> > +static inline struct local_binding *
>> > +local_binding_find(struct shash *local_bindings, const char *name)
>> > +{
>> > + return shash_find_data(local_bindings, name);
>> > +}
>> > +
>> > void binding_register_ovs_idl(struct ovsdb_idl *);
>> > void binding_run(struct binding_ctx_in *, struct binding_ctx_out *);
>> > bool binding_cleanup(struct ovsdb_idl_txn *ovnsb_idl_txn,
>> > diff --git a/controller/ovn-controller.c b/controller/ovn-controller.c
>> > index 9ad5be1c6..8f95fff1f 100644
>> > --- a/controller/ovn-controller.c
>> > +++ b/controller/ovn-controller.c
>> > @@ -1369,8 +1369,13 @@ static void init_physical_ctx(struct engine_node
>> *node,
>> >
>> > ovs_assert(br_int && chassis);
>> >
>> > + struct ovsrec_interface_table *iface_table =
>> > + (struct ovsrec_interface_table *)EN_OVSDB_GET(
>> > + engine_get_input("OVS_interface",
>> > + engine_get_input("physical_flow_changes", node)));
>>
>> I think we shouldn't try to get indirect input data (i.e. input of the
>> input). The engine design didn't take this into consideration, although
>> nothing could prevent a developer to do this (except code reviewing:)).
>> If the input is required to compute the output, just add it as direct
input
>> to the node.
>
>
> Sure I can do that. But we may need to have a no-op handler for these new
input nodes.
> Is that OK ?
Based on the above discussion, the node "physical_flow_change" is added
just to combine the "OVS_interface" and "ct_zones" node's data, so there is
no point to add the two nodes again directly as input to flow_output with
no-op handlers, which is meaningless. If we really want to have the
physical_flow_change node, I think the data should be passed in the
physical_flow_change node, just copy the references of the both input data
and it then becomes "physical_flow_changes" node's data, and flow_output
node and get it directly there. It achieves the same but not breaking I-P
engine rules.
>
> Thanks
> Numan
>
>>
>>
>> > struct ed_type_ct_zones *ct_zones_data =
>> > - engine_get_input_data("ct_zones", node);
>> > + engine_get_input_data("ct_zones",
>> > + engine_get_input("physical_flow_changes", node));
>> > struct simap *ct_zones = &ct_zones_data->current;
>> >
>> > p_ctx->sbrec_port_binding_by_name = sbrec_port_binding_by_name;
>> > @@ -1378,12 +1383,14 @@ static void init_physical_ctx(struct
engine_node
>> *node,
>> > p_ctx->mc_group_table = multicast_group_table;
>> > p_ctx->br_int = br_int;
>> > p_ctx->chassis_table = chassis_table;
>> > + p_ctx->iface_table = iface_table;
>> > p_ctx->chassis = chassis;
>> > p_ctx->active_tunnels = &rt_data->active_tunnels;
>> > p_ctx->local_datapaths = &rt_data->local_datapaths;
>> > p_ctx->local_lports = &rt_data->local_lports;
>> > p_ctx->ct_zones = ct_zones;
>> > p_ctx->mff_ovn_geneve = ed_mff_ovn_geneve->mff_ovn_geneve;
>> > + p_ctx->local_bindings = &rt_data->local_bindings;
>> > }
>> >
>> > static void init_lflow_ctx(struct engine_node *node,
>> > @@ -1791,6 +1798,70 @@ flow_output_port_groups_handler(struct
engine_node
>> *node, void *data)
>> > return _flow_output_resource_ref_handler(node, data,
>> REF_TYPE_PORTGROUP);
>> > }
>> >
>> > +struct ed_type_physical_flow_changes {
>> > + bool need_physical_run;
>> > + bool ovs_ifaces_changed;
>> > +};
>> > +
>> > +static bool
>> > +flow_output_physical_flow_changes_handler(struct engine_node *node,
void
>> *data)
>> > +{
>> > + struct ed_type_physical_flow_changes *pfc =
>> > + engine_get_input_data("physical_flow_changes", node);
>> > + struct ed_type_runtime_data *rt_data =
>> > + engine_get_input_data("runtime_data", node);
>> > +
>> > + struct ed_type_flow_output *fo = data;
>> > + struct physical_ctx p_ctx;
>> > + init_physical_ctx(node, rt_data, &p_ctx);
>> > +
>> > + engine_set_node_state(node, EN_UPDATED);
>> > + if (pfc->need_physical_run) {
>> > + pfc->need_physical_run = false;
>> > + physical_run(&p_ctx, &fo->flow_table);
>> > + return true;
>> > + }
>> > +
>> > + if (pfc->ovs_ifaces_changed) {
>> > + pfc->ovs_ifaces_changed = false;
>> > + return physical_handle_ovs_iface_changes(&p_ctx,
>> &fo->flow_table);
>> > + }
>> > +
>> > + return true;
>> > +}
>> > +
>> > +static void *
>> > +en_physical_flow_changes_init(struct engine_node *node OVS_UNUSED,
>> > + struct engine_arg *arg OVS_UNUSED)
>> > +{
>> > + struct ed_type_physical_flow_changes *data = xzalloc(sizeof
*data);
>> > + return data;
>> > +}
>> > +
>> > +static void
>> > +en_physical_flow_changes_cleanup(void *data OVS_UNUSED)
>> > +{
>> > +
>> > +}
>> > +
>> > +static void
>> > +en_physical_flow_changes_run(struct engine_node *node, void *data
>> OVS_UNUSED)
>> > +{
>> > + struct ed_type_physical_flow_changes *pfc = data;
>> > + pfc->need_physical_run = true;
>> > + engine_set_node_state(node, EN_UPDATED);
>> > +}
>> > +
>> > +static bool
>> > +physical_flow_changes_ovs_iface_handler(struct engine_node *node
>> OVS_UNUSED,
>> > + void *data OVS_UNUSED)
>> > +{
>> > + struct ed_type_physical_flow_changes *pfc = data;
>> > + pfc->ovs_ifaces_changed = true;
>> > + engine_set_node_state(node, EN_UPDATED);
>> > + return true;
>> > +}
>> > +
>> > struct ovn_controller_exit_args {
>> > bool *exiting;
>> > bool *restart;
>> > @@ -1914,6 +1985,7 @@ main(int argc, char *argv[])
>> > ENGINE_NODE(runtime_data, "runtime_data");
>> > ENGINE_NODE(mff_ovn_geneve, "mff_ovn_geneve");
>> > ENGINE_NODE(ofctrl_is_connected, "ofctrl_is_connected");
>> > + ENGINE_NODE(physical_flow_changes, "physical_flow_changes");
>> > ENGINE_NODE(flow_output, "flow_output");
>> > ENGINE_NODE(addr_sets, "addr_sets");
>> > ENGINE_NODE(port_groups, "port_groups");
>> > @@ -1933,13 +2005,19 @@ main(int argc, char *argv[])
>> > engine_add_input(&en_port_groups, &en_sb_port_group,
>> > port_groups_sb_port_group_handler);
>> >
>> > + engine_add_input(&en_physical_flow_changes, &en_ct_zones,
>> > + NULL);
>> > + engine_add_input(&en_physical_flow_changes, &en_ovs_interface,
>> > + physical_flow_changes_ovs_iface_handler);
>> > +
>> > engine_add_input(&en_flow_output, &en_addr_sets,
>> > flow_output_addr_sets_handler);
>> > engine_add_input(&en_flow_output, &en_port_groups,
>> > flow_output_port_groups_handler);
>> > engine_add_input(&en_flow_output, &en_runtime_data, NULL);
>> > - engine_add_input(&en_flow_output, &en_ct_zones, NULL);
>> > engine_add_input(&en_flow_output, &en_mff_ovn_geneve, NULL);
>> > + engine_add_input(&en_flow_output, &en_physical_flow_changes,
>> > + flow_output_physical_flow_changes_handler);
>> >
>> > engine_add_input(&en_flow_output, &en_ovs_open_vswitch, NULL);
>> > engine_add_input(&en_flow_output, &en_ovs_bridge, NULL);
>> > diff --git a/controller/physical.c b/controller/physical.c
>> > index 144aeb7bd..03eb677d1 100644
>> > --- a/controller/physical.c
>> > +++ b/controller/physical.c
>> > @@ -1780,6 +1780,57 @@ physical_run(struct physical_ctx *p_ctx,
>> > simap_destroy(&new_tunnel_to_ofport);
>> > }
>> >
>> > +bool
>> > +physical_handle_ovs_iface_changes(struct physical_ctx *p_ctx,
>> > + struct ovn_desired_flow_table
>> *flow_table)
>> > +{
>> > + const struct ovsrec_interface *iface_rec;
>> > + OVSREC_INTERFACE_TABLE_FOR_EACH_TRACKED (iface_rec,
>> p_ctx->iface_table) {
>> > + if (!strcmp(iface_rec->type, "geneve") ||
>> > + !strcmp(iface_rec->type, "patch")) {
>> > + return false;
>> > + }
>> > + }
>> > +
>> > + struct ofpbuf ofpacts;
>> > + ofpbuf_init(&ofpacts, 0);
>> > +
>> > + OVSREC_INTERFACE_TABLE_FOR_EACH_TRACKED (iface_rec,
>> p_ctx->iface_table) {
>> > + const char *iface_id = smap_get(&iface_rec->external_ids,
>> "iface-id");
>> > + if (!iface_id) {
>> > + continue;
>> > + }
>> > +
>> > + const struct local_binding *lb =
>> > + local_binding_find(p_ctx->local_bindings, iface_id);
>> > +
>> > + if (!lb || !lb->pb) {
>> > + continue;
>> > + }
>> > +
>> > + int64_t ofport = iface_rec->n_ofport ? *iface_rec->ofport : 0;
>> > + if (ovsrec_interface_is_deleted(iface_rec)) {
>> > + ofctrl_remove_flows(flow_table, &lb->pb->header_.uuid);
>> > + simap_find_and_delete(&localvif_to_ofport, iface_id);
>> > + } else {
>> > + if (!ovsrec_interface_is_new(iface_rec)) {
>> > + ofctrl_remove_flows(flow_table,
&lb->pb->header_.uuid);
>> > + }
>> > +
>> > + simap_put(&localvif_to_ofport, iface_id, ofport);
>> > + consider_port_binding(p_ctx->sbrec_port_binding_by_name,
>> > + p_ctx->mff_ovn_geneve,
p_ctx->ct_zones,
>> > + p_ctx->active_tunnels,
>> > + p_ctx->local_datapaths,
>> > + lb->pb, p_ctx->chassis,
>> > + flow_table, &ofpacts);
>> > + }
>> > + }
>> > +
>> > + ofpbuf_uninit(&ofpacts);
>> > + return true;
>> > +}
>> > +
>> > bool
>> > get_tunnel_ofport(const char *chassis_name, char *encap_ip, ofp_port_t
>> *ofport)
>> > {
>> > diff --git a/controller/physical.h b/controller/physical.h
>> > index dadf84ea1..9ca34436a 100644
>> > --- a/controller/physical.h
>> > +++ b/controller/physical.h
>> > @@ -49,11 +49,13 @@ struct physical_ctx {
>> > const struct ovsrec_bridge *br_int;
>> > const struct sbrec_chassis_table *chassis_table;
>> > const struct sbrec_chassis *chassis;
>> > + const struct ovsrec_interface_table *iface_table;
>> > const struct sset *active_tunnels;
>> > struct hmap *local_datapaths;
>> > struct sset *local_lports;
>> > const struct simap *ct_zones;
>> > enum mf_field_id mff_ovn_geneve;
>> > + struct shash *local_bindings;
>> > };
>> >
>> > void physical_register_ovs_idl(struct ovsdb_idl *);
>> > @@ -63,7 +65,8 @@ void physical_handle_port_binding_changes(struct
>> physical_ctx *,
>> > struct
ovn_desired_flow_table
>> *);
>> > void physical_handle_mc_group_changes(struct physical_ctx *,
>> > struct ovn_desired_flow_table
*);
>> > -
>> > +bool physical_handle_ovs_iface_changes(struct physical_ctx *,
>> > + struct ovn_desired_flow_table
*);
>> > bool get_tunnel_ofport(const char *chassis_name, char *encap_ip,
>> > ofp_port_t *ofport);
>> > #endif /* controller/physical.h */
>> > --
>> > 2.26.2
>> >
>> > _______________________________________________
>> > dev mailing list
>> > dev at openvswitch.org
>> > https://mail.openvswitch.org/mailman/listinfo/ovs-dev
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>>
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