diff --git a/vendor/go.uber.org/atomic/int64.go b/vendor/go.uber.org/atomic/int64.go
new file mode 100644
index 0000000..2bcbbfa
--- /dev/null
+++ b/vendor/go.uber.org/atomic/int64.go
@@ -0,0 +1,102 @@
+// @generated Code generated by gen-atomicint.
+
+// Copyright (c) 2020 Uber Technologies, Inc.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+package atomic
+
+import (
+	"encoding/json"
+	"strconv"
+	"sync/atomic"
+)
+
+// Int64 is an atomic wrapper around int64.
+type Int64 struct {
+	_ nocmp // disallow non-atomic comparison
+
+	v int64
+}
+
+// NewInt64 creates a new Int64.
+func NewInt64(i int64) *Int64 {
+	return &Int64{v: i}
+}
+
+// Load atomically loads the wrapped value.
+func (i *Int64) Load() int64 {
+	return atomic.LoadInt64(&i.v)
+}
+
+// Add atomically adds to the wrapped int64 and returns the new value.
+func (i *Int64) Add(n int64) int64 {
+	return atomic.AddInt64(&i.v, n)
+}
+
+// Sub atomically subtracts from the wrapped int64 and returns the new value.
+func (i *Int64) Sub(n int64) int64 {
+	return atomic.AddInt64(&i.v, -n)
+}
+
+// Inc atomically increments the wrapped int64 and returns the new value.
+func (i *Int64) Inc() int64 {
+	return i.Add(1)
+}
+
+// Dec atomically decrements the wrapped int64 and returns the new value.
+func (i *Int64) Dec() int64 {
+	return i.Sub(1)
+}
+
+// CAS is an atomic compare-and-swap.
+func (i *Int64) CAS(old, new int64) bool {
+	return atomic.CompareAndSwapInt64(&i.v, old, new)
+}
+
+// Store atomically stores the passed value.
+func (i *Int64) Store(n int64) {
+	atomic.StoreInt64(&i.v, n)
+}
+
+// Swap atomically swaps the wrapped int64 and returns the old value.
+func (i *Int64) Swap(n int64) int64 {
+	return atomic.SwapInt64(&i.v, n)
+}
+
+// MarshalJSON encodes the wrapped int64 into JSON.
+func (i *Int64) MarshalJSON() ([]byte, error) {
+	return json.Marshal(i.Load())
+}
+
+// UnmarshalJSON decodes JSON into the wrapped int64.
+func (i *Int64) UnmarshalJSON(b []byte) error {
+	var v int64
+	if err := json.Unmarshal(b, &v); err != nil {
+		return err
+	}
+	i.Store(v)
+	return nil
+}
+
+// String encodes the wrapped value as a string.
+func (i *Int64) String() string {
+	v := i.Load()
+	return strconv.FormatInt(int64(v), 10)
+}