store/tikv: remove use of fastrand (#22543)

Signed-off-by: disksing <i@disksing.com>

store/tikv/backoff.go

@@ -17,6 +17,7 @@ import (
 	"context"
 	"fmt"
 	"math"
+	"math/rand"
 	"strings"
 	"sync/atomic"
 	"time"
@@ -27,7 +28,6 @@ import (
 	"github.com/pingcap/tidb/kv"
 	"github.com/pingcap/tidb/metrics"
 	"github.com/pingcap/tidb/util/execdetails"
-	"github.com/pingcap/tidb/util/fastrand"
 	"github.com/pingcap/tidb/util/logutil"
 	"github.com/prometheus/client_golang/prometheus"
 	"go.uber.org/zap"
@@ -94,12 +94,12 @@ func NewBackoffFn(base, cap, jitter int) func(ctx context.Context, maxSleepMs in
 			sleep = expo(base, cap, attempts)
 		case FullJitter:
 			v := expo(base, cap, attempts)
-			sleep = int(fastrand.Uint32N(uint32(v)))
+			sleep = rand.Intn(v)
 		case EqualJitter:
 			v := expo(base, cap, attempts)
-			sleep = v/2 + int(fastrand.Uint32N(uint32(v/2)))
+			sleep = v/2 + rand.Intn(v/2)
 		case DecorrJitter:
-			sleep = int(math.Min(float64(cap), float64(base+int(fastrand.Uint32N(uint32(lastSleep*3-base))))))
+			sleep = int(math.Min(float64(cap), float64(base+rand.Intn(lastSleep*3-base))))
 		}
 		logutil.BgLogger().Debug("backoff",
 			zap.Int("base", base),

store/tikv/kv.go

@@ -35,7 +35,6 @@ import (
 	"github.com/pingcap/tidb/store/tikv/oracle/oracles"
 	"github.com/pingcap/tidb/store/tikv/tikvrpc"
 	"github.com/pingcap/tidb/util/execdetails"
-	"github.com/pingcap/tidb/util/fastrand"
 	"github.com/pingcap/tidb/util/logutil"
 	pd "github.com/tikv/pd/client"
 	"go.etcd.io/etcd/clientv3"
@@ -212,7 +211,7 @@ func newTikvStore(uuid string, pdClient pd.Client, spkv SafePointKV, client Clie
 		safePoint:       0,
 		spTime:          time.Now(),
 		closed:          make(chan struct{}),
-		replicaReadSeed: fastrand.Uint32(),
+		replicaReadSeed: rand.Uint32(),
 		memCache:        kv.NewCacheDB(),
 	}
 	store.lockResolver = newLockResolver(store)