txn: get txn status does not block if txn not found (pingcap#15300)

Afee2019 · Mar 12, 2020 · 35468b1 · 35468b1
1 parent d7a8eab
commit 35468b1
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Showing 2 changed files with 48 additions and 0 deletions.
diff --git a/session/pessimistic_test.go b/session/pessimistic_test.go
@@ -1096,3 +1096,40 @@ func (s *testPessimisticSuite) TestBatchPointGetLockIndex(c *C) {
 	tk.MustExec("rollback")
 	tk2.MustExec("rollback")
 }
+
+func (s *testPessimisticSuite) TestRollbackWakeupBlockedTxn(c *C) {
+	tk := testkit.NewTestKitWithInit(c, s.store)
+	tk2 := testkit.NewTestKitWithInit(c, s.store)
+	tk2.MustExec("use test")
+	tk.MustExec("use test")
+	tk.MustExec("drop table if exists t1")
+	tk.MustExec("create table t1 (c1 int primary key, c2 int, c3 int, unique key uk(c2))")
+	tk.MustExec("insert into t1 values (1, 1, 1)")
+	tk.MustExec("insert into t1 values (5, 5, 5)")
+	tk.MustExec("insert into t1 values (10, 10, 10)")
+
+	c.Assert(failpoint.Enable("github.com/pingcap/tidb/store/tikv/txnExpireRetTTL", "return"), IsNil)
+	c.Assert(failpoint.Enable("github.com/pingcap/tidb/store/tikv/getTxnStatusDelay", "return"), IsNil)
+	tk.MustExec("begin pessimistic")
+	tk2.MustExec("set innodb_lock_wait_timeout = 1")
+	tk2.MustExec("begin pessimistic")
+	tk.MustExec("update t1 set c3 = c3 + 1")
+	errCh := make(chan error)
+	go func() {
+		var err error
+		defer func() {
+			errCh <- err
+		}()
+		_, err = tk2.Exec("update t1 set c3 = 100 where c1 = 1")
+		if err != nil {
+			return
+		}
+	}()
+	time.Sleep(time.Millisecond * 30)
+	tk.MustExec("rollback")
+	err := <-errCh
+	c.Assert(err, IsNil)
+	tk2.MustExec("rollback")
+	c.Assert(failpoint.Disable("github.com/pingcap/tidb/store/tikv/txnExpireRetTTL"), IsNil)
+	c.Assert(failpoint.Disable("github.com/pingcap/tidb/store/tikv/getTxnStatusDelay"), IsNil)
+}
diff --git a/store/tikv/lock_resolver.go b/store/tikv/lock_resolver.go
@@ -432,6 +432,9 @@ func (lr *LockResolver) getTxnStatusFromLock(bo *Backoffer, l *Lock, callerStart
 	}
 
 	rollbackIfNotExist := false
+	failpoint.Inject("getTxnStatusDelay", func() {
+		time.Sleep(100 * time.Millisecond)
+	})
 	for {
 		status, err = lr.getTxnStatus(bo, l.TxnID, l.Primary, callerStartTS, currentTS, rollbackIfNotExist)
 		if err == nil {
@@ -460,9 +463,17 @@ func (lr *LockResolver) getTxnStatusFromLock(bo *Backoffer, l *Lock, callerStart
 				zap.Uint64("CallerStartTs", callerStartTS),
 				zap.Stringer("lock str", l))
 			if l.LockType == kvrpcpb.Op_PessimisticLock {
+				failpoint.Inject("txnExpireRetTTL", func() {
+					failpoint.Return(TxnStatus{l.TTL, 0, kvrpcpb.Action_NoAction},
+						errors.New("error txn not found and lock expired"))
+				})
 				return TxnStatus{}, nil
 			}
 			rollbackIfNotExist = true
+		} else {
+			if l.LockType == kvrpcpb.Op_PessimisticLock {
+				return TxnStatus{ttl: l.TTL}, nil
+			}
 		}
 	}
 }