If the I-P engine aborts in the middle of a run, the 'flow_output' node
change handlers or run callback might not be called.
As a side effect this may cause that Logical_Flow IDL tracked changes
are not processed during the iteration. As a consequence, if a
Logical_Flow was removed from the Southound DB, then its associated
cache entry (if any) will not be flushed.
This has two side effects:
1. Stale entries are kept in the cache until a full recompute or cache
flush happens.
2. If a new Logical_Flow is added to the Southbound and it happens to
have a UUID that matches one of a stale cache entry then
ovn-controller will install incorrect openflows.
IDL tracked changes are cleared at every iteration of ovn-controller.
Skipping the ovsdb_idl_track_clear() call if the I-P engine aborted is
not a valid option for now because it might lead to some of the IDL
changes to be processed twice.
Instead, lflow_handle_cached_flows() is called now at every iteration
of ovn-controller making sure deleted flows are removed from the cache.
Also, rename the 'flush-lflow-cache' unixctl command to
'lflow-cache/flush' to better match the style of other command names.
The old 'flush-lflow-cache' command is kept (as deprecated) to avoid
breaking existing CMS scripts.
Fixes: 2662498bfd13 ("ovn-controller: Persist the conjunction ids allocated for
conjuctive matches.")
Acked-by: Mark Michelson <[email protected]>
Signed-off-by: Dumitru Ceara <[email protected]>
---
v3:
- keep 'flush-lflow-cache' to avoid breaking CMS scripts.
- add man page entry for 'lflow-cache/flush'
---
controller/lflow.c | 30 +++++++++++++++++-------------
controller/lflow.h | 4 +++-
controller/ovn-controller.8.xml | 5 +++++
controller/ovn-controller.c | 24 ++++++++++++++++++++----
tests/ovn.at | 2 +-
5 files changed, 46 insertions(+), 19 deletions(-)
diff --git a/controller/lflow.c b/controller/lflow.c
index 2b7d356..02a4480 100644
--- a/controller/lflow.c
+++ b/controller/lflow.c
@@ -1583,19 +1583,6 @@ lflow_run(struct lflow_ctx_in *l_ctx_in, struct
lflow_ctx_out *l_ctx_out)
{
COVERAGE_INC(lflow_run);
- /* when lflow_run is called, it's possible that some of the logical flows
- * are deleted. We need to delete the lflow cache for these
- * lflows (if present), otherwise, they will not be deleted at all. */
- if (l_ctx_out->lflow_cache_map) {
- const struct sbrec_logical_flow *lflow;
- SBREC_LOGICAL_FLOW_TABLE_FOR_EACH_TRACKED (lflow,
- l_ctx_in->logical_flow_table) {
- if (sbrec_logical_flow_is_deleted(lflow)) {
- lflow_cache_delete(l_ctx_out->lflow_cache_map, lflow);
- }
- }
- }
-
add_logical_flows(l_ctx_in, l_ctx_out);
add_neighbor_flows(l_ctx_in->sbrec_port_binding_by_name,
l_ctx_in->mac_binding_table, l_ctx_in->local_datapaths,
@@ -1604,6 +1591,23 @@ lflow_run(struct lflow_ctx_in *l_ctx_in, struct
lflow_ctx_out *l_ctx_out)
l_ctx_out->flow_table);
}
+/* Should be called at every ovn-controller iteration before IDL tracked
+ * changes are cleared to avoid maintaining cache entries for flows that
+ * don't exist anymore.
+ */
+void
+lflow_handle_cached_flows(struct hmap *lflow_cache_map,
+ const struct sbrec_logical_flow_table *flow_table)
+{
+ const struct sbrec_logical_flow *lflow;
+
+ SBREC_LOGICAL_FLOW_TABLE_FOR_EACH_TRACKED (lflow, flow_table) {
+ if (sbrec_logical_flow_is_deleted(lflow)) {
+ lflow_cache_delete(lflow_cache_map, lflow);
+ }
+ }
+}
+
void
lflow_destroy(void)
{
diff --git a/controller/lflow.h b/controller/lflow.h
index ba79cc3..cf4f0e8 100644
--- a/controller/lflow.h
+++ b/controller/lflow.h
@@ -156,7 +156,9 @@ struct lflow_ctx_out {
};
void lflow_init(void);
-void lflow_run(struct lflow_ctx_in *, struct lflow_ctx_out *);
+void lflow_run(struct lflow_ctx_in *, struct lflow_ctx_out *);
+void lflow_handle_cached_flows(struct hmap *lflow_cache,
+ const struct sbrec_logical_flow_table *);
bool lflow_handle_changed_flows(struct lflow_ctx_in *, struct lflow_ctx_out *);
bool lflow_handle_changed_ref(enum ref_type, const char *ref_name,
struct lflow_ctx_in *, struct lflow_ctx_out *,
diff --git a/controller/ovn-controller.8.xml b/controller/ovn-controller.8.xml
index 29833c7..23ceb86 100644
--- a/controller/ovn-controller.8.xml
+++ b/controller/ovn-controller.8.xml
@@ -544,6 +544,11 @@
end-to-end latency in a large scale environment. See
<code>ovn-nbctl</code>(8) for more details.
</dd>
+
+ <dt><code>lflow-cache/flush</code></dt>
+ <dd>
+ Flushes the <code>ovn-controller</code> logical flow cache.
+ </dd>
</dl>
</p>
diff --git a/controller/ovn-controller.c b/controller/ovn-controller.c
index ef3e0e9..0f54ccd 100644
--- a/controller/ovn-controller.c
+++ b/controller/ovn-controller.c
@@ -80,7 +80,7 @@ static unixctl_cb_func cluster_state_reset_cmd;
static unixctl_cb_func debug_pause_execution;
static unixctl_cb_func debug_resume_execution;
static unixctl_cb_func debug_status_execution;
-static unixctl_cb_func flush_lflow_cache;
+static unixctl_cb_func lflow_cache_flush_cmd;
static unixctl_cb_func debug_delay_nb_cfg_report;
#define DEFAULT_BRIDGE_NAME "br-int"
@@ -2666,7 +2666,12 @@ main(int argc, char *argv[])
unixctl_command_register("recompute", "", 0, 0, engine_recompute_cmd,
NULL);
- unixctl_command_register("flush-lflow-cache", "", 0, 0, flush_lflow_cache,
+ unixctl_command_register("lflow-cache/flush", "", 0, 0,
+ lflow_cache_flush_cmd,
+ &flow_output_data->pd);
+ /* Keep deprecated 'flush-lflow-cache' command for now. */
+ unixctl_command_register("flush-lflow-cache", "[deprecated]", 0, 0,
+ lflow_cache_flush_cmd,
&flow_output_data->pd);
bool reset_ovnsb_idl_min_index = false;
@@ -2773,6 +2778,16 @@ main(int argc, char *argv[])
if (ovsdb_idl_has_ever_connected(ovnsb_idl_loop.idl) &&
northd_version_match) {
+
+ /* Unconditionally remove all deleted lflows from the lflow
+ * cache.
+ */
+ if (flow_output_data && flow_output_data->pd.lflow_cache_enabled) {
+ lflow_handle_cached_flows(
+ &flow_output_data->pd.lflow_cache_map,
+ sbrec_logical_flow_table_get(ovnsb_idl_loop.idl));
+ }
+
/* Contains the transport zones that this Chassis belongs to */
struct sset transport_zones = SSET_INITIALIZER(&transport_zones);
sset_from_delimited_string(&transport_zones,
@@ -3253,8 +3268,9 @@ engine_recompute_cmd(struct unixctl_conn *conn
OVS_UNUSED, int argc OVS_UNUSED,
}
static void
-flush_lflow_cache(struct unixctl_conn *conn OVS_UNUSED, int argc OVS_UNUSED,
- const char *argv[] OVS_UNUSED, void *arg_)
+lflow_cache_flush_cmd(struct unixctl_conn *conn OVS_UNUSED,
+ int argc OVS_UNUSED, const char *argv[] OVS_UNUSED,
+ void *arg_)
{
VLOG_INFO("User triggered lflow cache flush.");
struct flow_output_persistent_data *fo_pd = arg_;
diff --git a/tests/ovn.at b/tests/ovn.at
index 377a84e..785514d 100644
--- a/tests/ovn.at
+++ b/tests/ovn.at
@@ -22322,7 +22322,7 @@ check ovn-nbctl acl-add pg0 to-lport 1002 "outport ==
@pg0 && ip4 && udp.dst >=
wait_conj_id_count 2 "6 1 tcp" "7 1 udp"
AS_BOX([Flush lflow cache.])
-as hv1 ovn-appctl -t ovn-controller flush-lflow-cache
+as hv1 ovn-appctl -t ovn-controller lflow-cache/flush
wait_conj_id_count 2 "2 1" "3 1"
AS_BOX([Disable lflow caching.])
_______________________________________________
dev mailing list
[email protected]
https://mail.openvswitch.org/mailman/listinfo/ovs-dev
