git:master:f900e332: dispatcher: round robin with overload control algorithm - sr-dev

7 Jun 2024

Module: kamailio
Branch: master
Commit: f900e3325eb80ce8a266663e5fc251537436d449
URL: https://github.com/kamailio/kamailio/commit/f900e3325eb80ce8a266663e5fc25153...
Author: Daniel-Constantin Mierla miconda@gmail.com
Committer: Daniel-Constantin Mierla miconda@gmail.com
Date: 2024-06-07T07:44:33+02:00
dispatcher: round robin with overload control algorithm
---
Modified: src/modules/dispatcher/dispatch.c
---
Diff:  https://github.com/kamailio/kamailio/commit/f900e3325eb80ce8a266663e5fc25153...
Patch: https://github.com/kamailio/kamailio/commit/f900e3325eb80ce8a266663e5fc25153...
---

diff --git a/src/modules/dispatcher/dispatch.c b/src/modules/dispatcher/dispatch.c
index 8a225f35418..02e1f6e4a83 100644
--- a/src/modules/dispatcher/dispatch.c
+++ b/src/modules/dispatcher/dispatch.c
@@ -421,6 +421,25 @@ void ds_oc_prepare(ds_dest_t *dp)
    shuffle_uint100array(dp->ocdist);
 }
+/**
+ *
+ */
+static inline int ds_oc_skip(ds_set_t *dsg, int alg, int n)
+{
+	int ret = 0;
+
+	if(alg != DS_ALG_OVERLOAD) {
+		return 0;
+	}
+
+	if(dsg->dlist[n].ocdist[dsg->dlist[n].ocidx] == 1) {
+		ret = 0;
+	}
+	dsg->dlist[n].ocidx = (dsg->dlist[n].ocidx + 1) % 100;
+
+	return ret;
+}
+
 /**
  *
  */
@@ -2556,6 +2575,14 @@ int ds_manage_routes(sip_msg_t *msg, ds_select_state_t *rstate)
    			return -1;
    		xavp_filled = 1;
    		break;
+		case DS_ALG_OVERLOAD: /* 14 - round robin with overload control */
+			lock_get(&idx->lock);
+			hash = idx->last;
+			idx->last = (idx->last + 1) % idx->nr;
+			vlast = idx->last;
+			lock_release(&idx->lock);
+			ulast = 1;
+			break;
    	default:
    		LM_WARN("algo %d not implemented - using first entry...\n",
    				rstate->alg);
@@ -2571,7 +2598,9 @@ int ds_manage_routes(sip_msg_t *msg, ds_select_state_t *rstate)
    i = hash;
/* if selected address is inactive, find next active */
-	while(!xavp_filled && ds_skip_dst(idx->dlist[i].flags)) {
+	while(!xavp_filled
+			&& (ds_skip_dst(idx->dlist[i].flags)
+					|| ds_oc_skip(idx, rstate->alg, i))) {
    	if(ds_use_default != 0 && idx->nr != 1)
    		i = (i + 1) % (idx->nr - 1);
    	else
@@ -2580,7 +2609,8 @@ int ds_manage_routes(sip_msg_t *msg, ds_select_state_t *rstate)
    		/* back to start -- looks like no active dst */
    		if(ds_use_default != 0) {
    			i = idx->nr - 1;
-				if(ds_skip_dst(idx->dlist[i].flags))
+				if(ds_skip_dst(idx->dlist[i].flags)
+						|| ds_oc_skip(idx, rstate->alg, i))
    				return -1;
    			break;
    		} else {

    