irm: Revise naming API

This revises the naming API to treat names (or reg_name in the source)
as first-class citizens of the architecture. This is more in line with
the way they are described in the article.

Operations have been added to create/destroy names independently of
registering. This was previously done only as part of register, and
there was no way to delete a name from the IRMd.  The create call now
allows specifying a policy for load-balancing incoming flows for a
name. The default is the new round-robin load-balancer, the previous
behaviour is still available as a spillover load-balancer.

The register calls will still create a name if it doesn't exist, with
the default round-robin load-balancer.

The tools now have a "name" section, so the format is now

irm name <operation> <name> ...

Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks>
Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>

1 files changed, 20 insertions, 3 deletions

diff --git a/src/irmd/registry.c b/src/irmd/registry.c
index ef0bc8cc..66cc5af3 100644
--- a/src/irmd/registry.c
+++ b/src/irmd/registry.c
@@ -32,7 +32,6 @@
 
 #include <ouroboros/errno.h>
 #include <ouroboros/logs.h>
-#include <ouroboros/irm.h>
 #include <ouroboros/time_utils.h>
 
 #include "registry.h"
@@ -72,7 +71,8 @@ static int reg_entry_init(struct reg_entry * e,
         list_head_init(&e->reg_progs);
         list_head_init(&e->reg_pids);
 
-        e->name = name;
+        e->name   = name;
+        e->pol_lb = 0;
 
         if (pthread_condattr_init(&cattr))
                 goto fail_cattr;
@@ -286,7 +286,17 @@ int reg_entry_add_pid(struct reg_entry * e,
 
         i->pid = pid;
 
-        list_add(&i->next, &e->reg_pids);
+        /* load balancing policy assigns queue order for this process. */
+        switch(e->pol_lb) {
+        case LB_RR:    /* Round robin policy. */
+                list_add_tail(&i->next, &e->reg_pids);
+                break;
+        case LB_SPILL: /* Keep accepting flows on the current process */
+                list_add(&i->next, &e->reg_pids);
+                break;
+        default:
+                assert(false);
+        };
 
         if (e->state == REG_NAME_IDLE ||
             e->state == REG_NAME_AUTO_ACCEPT ||
@@ -300,6 +310,13 @@ int reg_entry_add_pid(struct reg_entry * e,
         return 0;
 }
 
+void reg_entry_set_policy(struct reg_entry * e,
+                          enum pol_balance   p)
+{
+        e->pol_lb = p;
+}
+
+
 static void reg_entry_check_state(struct reg_entry * e)
 {
         assert(e);