merged with fixes

internal/mtprotoedge/bulk_rpc_scheduler_test.go

@@ -0,0 +1,92 @@
+package mtprotoedge
+
+import (
+	"testing"
+	"time"
+)
+
+func TestBulkRPCSchedulerKeepsOverflowBehindGate(t *testing.T) {
+	scheduler := newBulkRPCScheduler(2)
+	first := scheduler.reserve()
+	second := scheduler.reserve()
+	third := scheduler.reserve()
+	woken := make(chan bool, 1)
+	third.subscribe(func(success bool) { woken <- success })
+	select {
+	case <-woken:
+		t.Fatal("overflow bulk handler became runnable before a slot was released")
+	default:
+	}
+	first.release()
+	select {
+	case success := <-woken:
+		if !success {
+			t.Fatal("overflow bulk handler was canceled instead of admitted")
+		}
+	case <-time.After(time.Second):
+		t.Fatal("overflow bulk handler did not become runnable")
+	}
+	second.release()
+	third.release()
+}
+
+func TestBulkRPCSchedulerCloseCancelsWaiters(t *testing.T) {
+	scheduler := newBulkRPCScheduler(1)
+	active := scheduler.reserve()
+	waiting := scheduler.reserve()
+	woken := make(chan bool, 1)
+	waiting.subscribe(func(success bool) { woken <- success })
+	scheduler.close()
+	select {
+	case success := <-woken:
+		if success {
+			t.Fatal("closed bulk scheduler granted a waiting handler")
+		}
+	case <-time.After(time.Second):
+		t.Fatal("closed bulk scheduler did not cancel waiter")
+	}
+	active.release()
+}
+
+func TestBulkRPCAdmissionDoesNotReserveGlobalSlotBeforeSessionCredit(t *testing.T) {
+	scheduler := newBulkRPCScheduler(1)
+	state := newOutboundStateWithLimits(newOutboundTrackedBudget(1<<20), 128, 1<<20)
+	state.bulkMax = 1
+	activeCredit := state.reserveBulkCredit()
+	waitingCredit := state.reserveBulkCredit()
+	admission := newBulkRPCAdmission(scheduler)
+	woken := make(chan bool, 1)
+	admission.subscribeAfter(waitingCredit.credit, func(success bool) { woken <- success })
+
+	scheduler.mu.Lock()
+	inUseBeforeCredit := scheduler.inUse
+	scheduler.mu.Unlock()
+	if inUseBeforeCredit != 0 {
+		t.Fatalf("credit-blocked request reserved %d global slots, want 0", inUseBeforeCredit)
+	}
+	select {
+	case <-woken:
+		t.Fatal("credit-blocked request became runnable")
+	default:
+	}
+
+	activeCredit.releaseIfOwned()
+	select {
+	case success := <-woken:
+		if !success {
+			t.Fatal("request was canceled after session credit became available")
+		}
+	case <-time.After(time.Second):
+		t.Fatal("request did not enter global scheduler after session credit")
+	}
+	scheduler.mu.Lock()
+	inUseAfterCredit := scheduler.inUse
+	scheduler.mu.Unlock()
+	if inUseAfterCredit != 1 {
+		t.Fatalf("admitted request reserved %d global slots, want 1", inUseAfterCredit)
+	}
+
+	admission.release()
+	waitingCredit.releaseIfOwned()
+	state.closeBulkWindow()
+}