aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorAlexander Couzens <lynxis@fe80.eu>2021-02-15 01:07:45 +0100
committerlynxis lazus <lynxis@fe80.eu>2021-02-19 10:41:50 +0000
commitd8a8d980535468d1f8642cdcf796b2d675c7b8df (patch)
tree771285fa22866d4470ee16488e27356201a7e273
parentbf5d0dbdec94f58bdbedadd92db7111e51fa7053 (diff)
gprs_ns2: implement a simple load sharing for UDP
Implement the load sharing based on modulo of the LSP. As long the gprs_ns2 doesn't support the resource distribution function (48.016 ยง 4.4a) this simple approach is good enought. Fixes: OS#4836 Change-Id: I8c2fe5d647694886ac600470fca6ea5d5d210a85
-rw-r--r--src/gb/gprs_ns2.c41
-rw-r--r--tests/gb/gprs_ns2_test.c94
-rw-r--r--tests/gb/gprs_ns2_test.ok8
3 files changed, 142 insertions, 1 deletions
diff --git a/src/gb/gprs_ns2.c b/src/gb/gprs_ns2.c
index bc4db53e..e2907343 100644
--- a/src/gb/gprs_ns2.c
+++ b/src/gb/gprs_ns2.c
@@ -384,6 +384,45 @@ static struct gprs_ns2_vc *ns2_load_sharing_modulor(
return NULL;
}
+/* 4.4.2 Load Sharing function for the IP Sub-Network
+ *
+ * Implement a simple approach for UDP load sharing of data weight based on the modulo of the lsp.
+ *
+ * E.g. 3 NSVC: 1st weight 5, 2nd weight 3, 3rd weight 1, lsp = 3.
+ * sum all weights = 9
+ * target_weight = lsp % sum = 3
+ *
+ * 1st NSVC will be the target for 0-4
+ * 2nd NSVC will be the target for 5-7
+ * 3rd NSVC will be the target for 8
+ *
+ * The 1st NSVC will be used.
+ * E.g. lsp = 7. The 2nd NSVC will used.
+ */
+static struct gprs_ns2_vc *ns2_load_sharing_weight_modulo(
+ struct gprs_ns2_nse *nse,
+ uint16_t bvci,
+ uint32_t load_selector)
+{
+ struct gprs_ns2_vc *tmp;
+ uint32_t mod;
+ uint32_t i = 0;
+
+ if (nse->nsvc_count == 0)
+ return NULL;
+
+ mod = (bvci + load_selector) % nse->sum_data_weight;
+ llist_for_each_entry(tmp, &nse->nsvc, list) {
+ if (!ns2_vc_is_unblocked(tmp))
+ continue;
+ if (i == mod || mod < i + tmp->data_weight)
+ return tmp;
+ i += tmp->data_weight;
+ }
+
+ return NULL;
+}
+
/* pick the first available data NSVC - no load sharing */
struct gprs_ns2_vc *ns2_load_sharing_first(struct gprs_ns2_nse *nse)
{
@@ -421,7 +460,7 @@ static struct gprs_ns2_vc *ns2_load_sharing(
nsvc = ns2_load_sharing_signal(nse);
} else {
/* data with load sharing parameter */
- nsvc = ns2_load_sharing_first(nse);
+ nsvc = ns2_load_sharing_weight_modulo(nse, bvci, link_selector);
}
break;
}
diff --git a/tests/gb/gprs_ns2_test.c b/tests/gb/gprs_ns2_test.c
index 6d71a8c6..d8ed06fa 100644
--- a/tests/gb/gprs_ns2_test.c
+++ b/tests/gb/gprs_ns2_test.c
@@ -60,6 +60,18 @@ static int ns_prim_cb(struct osmo_prim_hdr *oph, void *ctx)
return 0;
}
+static int gp_send_to_ns(struct gprs_ns2_inst *nsi, struct msgb *msg, uint16_t nsei, uint16_t bvci, uint32_t lsp)
+{
+ struct osmo_gprs_ns2_prim nsp = {};
+ nsp.nsei = nsei;
+ nsp.bvci = bvci;
+ nsp.u.unitdata.link_selector = lsp;
+ osmo_prim_init(&nsp.oph, SAP_NS, GPRS_NS2_PRIM_UNIT_DATA,
+ PRIM_OP_REQUEST, msg);
+ return gprs_ns2_recv_prim(nsi, &nsp.oph);
+}
+
+
static struct msgb *get_pdu(struct gprs_ns2_vc_bind *bind, enum ns_pdu_type pdu_type)
{
struct gprs_ns_hdr *nsh;
@@ -88,6 +100,12 @@ static bool find_pdu(struct gprs_ns2_vc_bind *bind, enum ns_pdu_type pdu_type)
return false;
}
+static unsigned int count_pdus(struct gprs_ns2_vc_bind *bind)
+{
+ struct osmo_wqueue *queue = bind->priv;
+ return llist_count(&queue->msg_queue);
+}
+
static void clear_pdus(struct gprs_ns2_vc_bind *bind)
{
struct osmo_wqueue *queue = bind->priv;
@@ -370,6 +388,81 @@ void test_unitdata(void *ctx)
printf("--- Finish unitdata test\n");
}
+void test_unitdata_weights(void *ctx)
+{
+ struct gprs_ns2_inst *nsi;
+ struct gprs_ns2_vc_bind *bind[3];
+ struct gprs_ns2_vc_bind *loopbind;
+ struct gprs_ns2_nse *nse;
+ struct gprs_ns2_vc *nsvc[3];
+ struct gprs_ns2_vc *loop[3];
+
+ struct msgb *msg, *other;
+ char idbuf[32];
+ int i;
+
+ printf("--- Testing unitdata weight test\n");
+ osmo_wqueue_clear(unitdata);
+ printf("---- Create NSE + Binds\n");
+ nsi = gprs_ns2_instantiate(ctx, ns_prim_cb, NULL);
+ bind[0] = dummy_bind(nsi, "bblock1");
+ bind[1] = dummy_bind(nsi, "bblock2");
+ bind[2] = dummy_bind(nsi, "bblock3");
+ loopbind = loopback_bind(nsi, "loopback");
+ nse = gprs_ns2_create_nse(nsi, 1004, GPRS_NS2_LL_UDP, GPRS_NS2_DIALECT_STATIC_ALIVE);
+ OSMO_ASSERT(nse);
+
+ /* data weights are
+ * nsvc[0] = 1
+ * nsvc[1] = 2
+ * nsvc[2] = 3
+ */
+ for (i = 0; i < 3; i++) {
+ printf("---- Create NSVC[%d]\n", i);
+ snprintf(idbuf, sizeof(idbuf), "NSE%05u-dummy-%i", nse->nsei, i);
+ nsvc[i] = ns2_vc_alloc(bind[i], nse, false, GPRS_NS2_VC_MODE_ALIVE, idbuf);
+ loop[i] = loopback_nsvc(loopbind, nsvc[i]);
+ OSMO_ASSERT(nsvc[i]);
+ nsvc[i]->data_weight = i + 1;
+ ns2_vc_fsm_start(nsvc[i]);
+ OSMO_ASSERT(!ns2_vc_is_unblocked(nsvc[i]));
+ ns2_tx_alive_ack(loop[i]);
+ OSMO_ASSERT(ns2_vc_is_unblocked(nsvc[i]));
+ }
+
+ /* all nsvcs are alive */
+ printf("---- Send UNITDATA to all NSVCs\n");
+ for (i = 0; i < 3; i++) {
+ msg = generate_unitdata("test_unitdata_weight");
+ ns2_recv_vc(nsvc[i], msg);
+ other = msgb_dequeue(&unitdata->msg_queue);
+ OSMO_ASSERT(msg == other);
+ other = msgb_dequeue(&unitdata->msg_queue);
+ OSMO_ASSERT(NULL == other);
+ msgb_free(msg);
+ }
+
+ /* nsvc[1] should be still good */
+ printf("---- Send BSSGP data to the NSE to test unitdata over NSVC[1]\n");
+ for (i = 0; i < 3; i++)
+ clear_pdus(bind[i]);
+
+ for (i = 0; i < 12; i++) {
+ msg = generate_unitdata("test_unitdata_weight2");
+ gp_send_to_ns(nsi, msg, 1004, 1, i + 1);
+ }
+
+ for (i = 0; i < 3; i++)
+ fprintf(stderr, "count_pdus(bind[%d]) = %d\n", i, count_pdus(bind[i]));
+
+ for (i = 0; i < 3; i++) {
+ OSMO_ASSERT(count_pdus(bind[i]) == nsvc[i]->data_weight * 2);
+ }
+
+ gprs_ns2_free(nsi);
+ printf("--- Finish unitdata weight test\n");
+}
+
void test_mtu(void *ctx)
{
struct gprs_ns2_inst *nsi;
@@ -440,6 +533,7 @@ int main(int argc, char **argv)
test_nse_transfer_cap(ctx);
test_block_unblock_nsvc(ctx);
test_unitdata(ctx);
+ test_unitdata_weights(ctx);
test_mtu(ctx);
printf("===== NS2 protocol test END\n\n");
diff --git a/tests/gb/gprs_ns2_test.ok b/tests/gb/gprs_ns2_test.ok
index f40579f3..40a1528b 100644
--- a/tests/gb/gprs_ns2_test.ok
+++ b/tests/gb/gprs_ns2_test.ok
@@ -20,6 +20,14 @@
---- Try to receive over blocked NSVC[0]
---- Receive over NSVC[1]
--- Finish unitdata test
+--- Testing unitdata weight test
+---- Create NSE + Binds
+---- Create NSVC[0]
+---- Create NSVC[1]
+---- Create NSVC[2]
+---- Send UNITDATA to all NSVCs
+---- Send BSSGP data to the NSE to test unitdata over NSVC[1]
+--- Finish unitdata weight test
--- Testing mtu test
---- Create NSE + Binds
---- Create NSVC[0]