pespin has submitted this change. (
https://gerrit.osmocom.org/c/libosmo-sigtran/+/39391?usp=email )
Change subject: AS loadsharing: Implement AS loadshare, skip unavailable
AS/lset when choosing
......................................................................
AS loadsharing: Implement AS loadshare, skip unavailable AS/lset when choosing
Pick normal route containing destination AS/lset to serve a given
func(<OPC,DPC,SLS>)=eSLS on a round-robin base.
If normal route becomes unavailable, pick an alternative route in a
similar way. This alternative route will be used until itself becomes
unavailable or the normal route becomes available again.
Related: SYS#7112
Change-Id: I928fb1ef5db6922f1386a188e3fbf9e70780f25d
---
M src/osmo_ss7_combined_linkset.c
M src/osmo_ss7_hmrt.c
M src/ss7_combined_linkset.h
M src/xua_snm.c
M tests/ss7/ss7_test.c
M tests/vty/osmo_stp_route_prio.vty
6 files changed, 67 insertions(+), 21 deletions(-)
Approvals:
Jenkins Builder: Verified
pespin: Looks good to me, approved
osmith: Looks good to me, but someone else must approve
diff --git a/src/osmo_ss7_combined_linkset.c b/src/osmo_ss7_combined_linkset.c
index 90a54f6..99b0c79 100644
--- a/src/osmo_ss7_combined_linkset.c
+++ b/src/osmo_ss7_combined_linkset.c
@@ -49,6 +49,20 @@
* link set) or of an alternative link set (combined link set)."
*****************************************************************************/
+static inline struct llist_head *_ss7_llist_round_robin(struct llist_head
*list, void **state)
+{
+ struct llist_head *e = *state;
+ if (!e || e->next == list)
+ e = list;
+ e = e->next;
+ if (e == list)
+ e = NULL;
+ *state = e;
+ return e;
+}
+#define ss7_llist_round_robin(list, state, struct_type, entry_name) \
+ llist_entry(_ss7_llist_round_robin(list, state), struct_type,
entry_name)
+
/*! \brief Insert combined_link into its routing table
* \param[in] clset Combined link to be inserted into its routing table
* \returns 0 on success, negative on error
@@ -135,6 +149,14 @@
clset->esls_table[i].alt_rt = NULL;
}
+ /* Update round robin state */
+ if (rt == clset->last_route_roundrobin) {
+ ss7_llist_round_robin(&clset->routes,
&clset->last_route_roundrobin, struct osmo_ss7_route, list);
+ /* If there's only one left, remove state: */
+ if (rt == clset->last_route_roundrobin)
+ clset->last_route_roundrobin = NULL;
+ }
+
llist_del(&rt->list);
rt->clset = NULL;
clset->num_routes--;
@@ -172,6 +194,27 @@
return NULL;
}
+static struct osmo_ss7_route
*ss7_combined_linkset_select_route_roundrobin(struct osmo_ss7_combined_linkset
*clset)
+{
+ struct osmo_ss7_route *rt;
+ struct osmo_ss7_route *rt_found = NULL;
+ unsigned int i = 0;
+
+ while (i < clset->num_routes) {
+ i++;
+ rt = ss7_llist_round_robin(&clset->routes,
&clset->last_route_roundrobin, struct osmo_ss7_route, list);
+ if (ss7_route_is_available(rt)) {
+ rt_found = rt;
+ break;
+ }
+ }
+
+ if (!rt_found)
+ return NULL;
+
+ return rt_found;
+}
+
struct osmo_ss7_route *
ss7_combined_linkset_lookup_route(struct osmo_ss7_combined_linkset *clset,
const struct osmo_ss7_route_label *rtlabel)
{
@@ -192,20 +235,20 @@
return rt;
}
- /* TODO: Check if the AS/linkset in rt is actually UP and can be
- * used, otherwise start ITU Q.704 section 7 "forced rerouting"
prcoedure:
- * we need to pick a temporary dst (update the esls_table entry) while
the
- * original one is DOWN. */
+ /* No current route available, try to find a new current route: */
- /* We need to pick a new AS/linkset from the combined linkset and cache
- * it so it is always used for this eSLS: */
- /* FIXME: for now we simply take the first AS in the combined linksed,
to be improved later... */
- rt = llist_first_entry_or_null(&clset->routes, struct osmo_ss7_route,
list);
+ /* No normal route selected yet: */
+ if (!eslse->normal_rt) {
+ rt = ss7_combined_linkset_select_route_roundrobin(clset);
+ /* Either a normal route was selected or none found: */
+ eslse->normal_rt = rt;
+ return rt;
+ }
- /* TODO: here we'd need to actually check if dst AS/linkset in the route
- * is actually UP, otherwise pick next one in the roundrobin list... */
+ /* Normal route unavailable and no alternative route (or unavailable
too).
+ * start ITU Q.704 section 7 "forced rerouting" procedure: */
+ rt = ss7_combined_linkset_select_route_roundrobin(clset);
if (rt)
- clset->esls_table[esls].normal_rt = rt;
-
+ eslse->alt_rt = rt;
return rt;
}
diff --git a/src/osmo_ss7_hmrt.c b/src/osmo_ss7_hmrt.c
index 1e000b4..72d5adc 100644
--- a/src/osmo_ss7_hmrt.c
+++ b/src/osmo_ss7_hmrt.c
@@ -180,12 +180,6 @@
dpc, osmo_ss7_pointcode_print(inst,
dpc), rt_name);
}
- if (osmo_ss7_as_down(as)) {
- LOGP(DLSS7, LOGL_ERROR, "Unable to route HMRT
message: the AS %s is down\n",
- as->cfg.name);
- return -ENETDOWN;
- }
-
rate_ctr_inc2(as->ctrg, SS7_AS_CTR_TX_MSU_TOTAL);
switch (as->cfg.proto) {
diff --git a/src/ss7_combined_linkset.h b/src/ss7_combined_linkset.h
index e2f9c9d..b80a007 100644
--- a/src/ss7_combined_linkset.h
+++ b/src/ss7_combined_linkset.h
@@ -33,6 +33,7 @@
/*! list of \ref osmo_ss7_route */
struct llist_head routes;
unsigned int num_routes;
+ void *last_route_roundrobin;
struct {
uint32_t pc;
diff --git a/src/xua_snm.c b/src/xua_snm.c
index acdfe0c..1481178 100644
--- a/src/xua_snm.c
+++ b/src/xua_snm.c
@@ -347,7 +347,7 @@
.sls = 0,
};
- /* FIXME: don't just check for a route; but also check
if the route is "active" */
+ /* Check if there's an "active" route available: */
if (ss7_instance_lookup_route(s7i, &rtlabel))
is_available = true;
diff --git a/tests/ss7/ss7_test.c b/tests/ss7/ss7_test.c
index 95fa1b1..f61ee0a 100644
--- a/tests/ss7/ss7_test.c
+++ b/tests/ss7/ss7_test.c
@@ -154,6 +154,7 @@
{
struct osmo_ss7_route_table *rtbl;
struct osmo_ss7_linkset *lset_a, *lset_b;
+ struct osmo_ss7_link *l_a, *l_b;
struct osmo_ss7_route *rt, *rt12, *rtdef;
struct osmo_ss7_route_label route_label;
@@ -173,8 +174,15 @@
lset_a = ss7_linkset_find_or_create(s7i, "a", 100);
OSMO_ASSERT(lset_a);
+ l_a = ss7_link_find_or_create(lset_a, 0);
+ OSMO_ASSERT(l_a);
+ l_a->cfg.adm_state = OSMO_SS7_LS_ENABLED;
+
lset_b = ss7_linkset_find_or_create(s7i, "b", 200);
OSMO_ASSERT(lset_b);
+ l_b = ss7_link_find_or_create(lset_b, 0);
+ OSMO_ASSERT(l_b);
+ l_b->cfg.adm_state = OSMO_SS7_LS_ENABLED;
/* route with full mask */
route_label = RT_LABEL(0, 12, 0);
diff --git a/tests/vty/osmo_stp_route_prio.vty
b/tests/vty/osmo_stp_route_prio.vty
index 6f60d9a..2b7cec6 100644
--- a/tests/vty/osmo_stp_route_prio.vty
+++ b/tests/vty/osmo_stp_route_prio.vty
@@ -87,6 +87,6 @@
3.2.1/14 INACC 0 5 as2 UNAVAIL ? UNAVAIL
3.2.1/14 INACC 7 6 as1 UNAVAIL ? UNAVAIL
-OsmoSTP(config-cs7-rt)# ! NOW TEST LOOKUP WORKS AS DESIRED (as3 PICKED):
+OsmoSTP(config-cs7-rt)# ! NOW TEST LOOKUP FAILS AS EXPECTED (all route links
are down):
OsmoSTP(config-cs7-rt)# do show cs7 instance 0 route-lookup 3.2.1 from 0.0.1
sls 0
-pc=6161=3.2.1 mask=0x3fff=7.255.7 via AS as3 proto=m3ua
+No route found for label 'OPC=1=0.0.1,DPC=6161=3.2.1,SLS=0'
--
To view, visit https://gerrit.osmocom.org/c/libosmo-sigtran/+/39391?usp=email
To unsubscribe, or for help writing mail filters, visit
https://gerrit.osmocom.org/settings?usp=email
Gerrit-MessageType: merged
Gerrit-Project: libosmo-sigtran
Gerrit-Branch: master
Gerrit-Change-Id: I928fb1ef5db6922f1386a188e3fbf9e70780f25d
Gerrit-Change-Number: 39391
Gerrit-PatchSet: 11
Gerrit-Owner: pespin <[email protected]>
Gerrit-Reviewer: Jenkins Builder
Gerrit-Reviewer: osmith <[email protected]>
Gerrit-Reviewer: pespin <[email protected]>
Gerrit-CC: laforge <[email protected]>
