diff --git a/go/pools/smartconnpool/waitlist.go b/go/pools/smartconnpool/waitlist.go index d4abeade0ac..633d330b7d0 100644 --- a/go/pools/smartconnpool/waitlist.go +++ b/go/pools/smartconnpool/waitlist.go @@ -88,11 +88,15 @@ func (wl *waitlist[C]) expire(force bool) { // or remove everything if force is true for e := wl.list.Front(); e != nil; e = e.Next() { if force || e.Value.ctx.Err() != nil { - wl.list.Remove(e) expired = append(expired, e) continue } } + // remove the expired waiters from the waitlist after traversing it + for _, e := range expired { + wl.list.Remove(e) + } + wl.mu.Unlock() // once all the expired waiters have been removed from the waitlist, wake them up one by one diff --git a/go/pools/smartconnpool/waitlist_test.go b/go/pools/smartconnpool/waitlist_test.go new file mode 100644 index 00000000000..59d5f677447 --- /dev/null +++ b/go/pools/smartconnpool/waitlist_test.go @@ -0,0 +1,65 @@ +/* +Copyright 2023 The Vitess Authors. + +Licensed under the Apache License, Version 2.0 (the "License"); +you may not use this file except in compliance with the License. +You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + +Unless required by applicable law or agreed to in writing, software +distributed under the License is distributed on an "AS IS" BASIS, +WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +See the License for the specific language governing permissions and +limitations under the License. +*/ + +package smartconnpool + +import ( + "context" + "sync/atomic" + "testing" + "time" + + "github.com/stretchr/testify/assert" +) + +func TestWaitlistExpireWithMultipleWaiters(t *testing.T) { + wait := waitlist[*TestConn]{} + wait.init() + + ctx, cancel := context.WithTimeout(context.Background(), 10*time.Millisecond) + defer cancel() + + waiterCount := 2 + expireCount := atomic.Int32{} + + for i := 0; i < waiterCount; i++ { + go func() { + _, err := wait.waitForConn(ctx, nil) + if err != nil { + expireCount.Add(1) + } + }() + } + + // Wait for the context to expire + <-ctx.Done() + + // Expire the waiters + wait.expire(false) + + // Wait for the notified goroutines to finish + timeout := time.After(1 * time.Second) + for expireCount.Load() != int32(waiterCount) { + select { + case <-timeout: + t.Fatalf("Timed out waiting for all waiters to expire. Wanted %d, got %d", waiterCount, expireCount.Load()) + case <-time.After(10 * time.Millisecond): + // try again + } + } + + assert.Equal(t, int32(waiterCount), expireCount.Load()) +}