use IPSet.Diff for SIGUSR1 decision logic

Signed-off-by: AkshatDudeja77 <akshat.dudeja77@gmail.com>

Author: AkshatDudeja77

cmd/compute-domain-daemon/main.go

@@ -359,18 +359,23 @@ func IMEXDaemonUpdateLoopWithIPs(ctx context.Context, controller *Controller, cl
 	}
 }
 
-func shouldSendSIGUSR1(oldIPs, newIPs map[string]struct{}, updated, fresh bool) bool {
+// shouldSendSIGUSR1 determines whether the IMEX daemon should be
+// signaled to re-resolve and reconnect to peers.
+//
+// updated indicates whether the DNS/IP mapping actually changed.
+// fresh indicates whether the IMEX daemon process was just started.
+//
+// The signal is sent only when:
+// - the mapping was updated,
+// - the process is not fresh, and
+// - at least one new IP (peer) was added.
+func shouldSendSIGUSR1(oldIPs, newIPs IPSet, updated, fresh bool) bool {
 	if !updated || fresh {
 		return false
 	}
 
-	for ip := range newIPs {
-		if _, existed := oldIPs[ip]; !existed {
-			return true
-		}
-	}
-
-	return false
+	added, _ := oldIPs.Diff(newIPs)
+	return len(added) > 0
 }
 
 // IMEXDaemonUpdateLoopWithDNSNames reacts to ComputeDomain status changes by
@@ -412,7 +417,7 @@ func IMEXDaemonUpdateLoopWithDNSNames(ctx context.Context, controller *Controlle
 			// - the process is fresh (has newly been started), or
 			// - this was a noop update, or
 			// - no new peers were added (i.e. the update only removes nodes or keeps the set unchanged).
-			if !shouldSendSIGUSR1(oldIPs, dnsNameManager.ipToDNSName, updated, fresh) {
+			if !shouldSendSIGUSR1(IPSet(oldIPs), IPSet(dnsNameManager.ipToDNSName), updated, fresh) {
 				break
 			}