feat: check kill signal in 2pc committer (#1084)

Signed-off-by: ekexium <eke@fastmail.com>
Co-authored-by: disksing <i@disksing.com>

error/error.go

@@ -64,13 +64,13 @@ var (
 	// ErrTiFlashServerTimeout is the error when tiflash server is timeout.
 	ErrTiFlashServerTimeout = errors.New("tiflash server timeout")
 	// ErrQueryInterrupted is the error when the query is interrupted.
-	ErrQueryInterrupted = errors.New("query interruppted")
+	ErrQueryInterrupted = errors.New("query interrupted")
 	// ErrTiKVStaleCommand is the error that the command is stale in tikv.
 	ErrTiKVStaleCommand = errors.New("tikv stale command")
 	// ErrTiKVMaxTimestampNotSynced is the error that tikv's max timestamp is not synced.
 	ErrTiKVMaxTimestampNotSynced = errors.New("tikv max timestamp not synced")
 	// ErrLockAcquireFailAndNoWaitSet is the error that acquire the lock failed while no wait is setted.
-	ErrLockAcquireFailAndNoWaitSet = errors.New("lock acquired failed and no wait is setted")
+	ErrLockAcquireFailAndNoWaitSet = errors.New("lock acquired failed and no wait is set")
 	// ErrResolveLockTimeout is the error that resolve lock timeout.
 	ErrResolveLockTimeout = errors.New("resolve lock timeout")
 	// ErrLockWaitTimeout is the error that wait for the lock is timeout.

txnkv/transaction/2pc.go

@@ -1048,7 +1048,27 @@ func (c *twoPhaseCommitter) doActionOnGroupMutations(bo *retry.Backoffer, action
 }
 
 // doActionOnBatches does action to batches in parallel.
-func (c *twoPhaseCommitter) doActionOnBatches(bo *retry.Backoffer, action twoPhaseCommitAction, batches []batchMutations) error {
+func (c *twoPhaseCommitter) doActionOnBatches(
+	bo *retry.Backoffer, action twoPhaseCommitAction,
+	batches []batchMutations,
+) error {
+	// killSignal should never be nil for TiDB
+	if c.txn != nil && c.txn.vars != nil && c.txn.vars.Killed != nil {
+		// Do not reset the killed flag here. Let the upper layer reset the flag.
+		// Before it resets, any request is considered valid to be killed.
+		status := atomic.LoadUint32(c.txn.vars.Killed)
+		if status != 0 {
+			logutil.BgLogger().Info(
+				"query is killed", zap.Uint32(
+					"signal",
+					status,
+				),
+			)
+			// TODO: There might be various signals besides a query interruption,
+			// but we are unable to differentiate them, because the definition is in TiDB.
+			return errors.WithStack(tikverr.ErrQueryInterrupted)
+		}
+	}
 	if len(batches) == 0 {
 		return nil
 	}

txnkv/transaction/pessimistic.go

@@ -214,18 +214,6 @@ func (action actionPessimisticLock) handleSingleBatch(
 				return nil
 			}
 		}
-
-		// Handle the killed flag when waiting for the pessimistic lock.
-		// When a txn runs into LockKeys() and backoff here, it has no chance to call
-		// executor.Next() and check the killed flag.
-		if action.Killed != nil {
-			// Do not reset the killed flag here!
-			// actionPessimisticLock runs on each region parallelly, we have to consider that
-			// the error may be dropped.
-			if atomic.LoadUint32(action.Killed) == 1 {
-				return errors.WithStack(tikverr.ErrQueryInterrupted)
-			}
-		}
 	}
 }
 

txnkv/transaction/txn.go

@@ -1111,12 +1111,6 @@ func (txn *KVTxn) lockKeys(ctx context.Context, lockCtx *tikv.LockCtx, fn func()
 			lockCtx.Stats.Mu.BackoffTypes = append(lockCtx.Stats.Mu.BackoffTypes, bo.GetTypes()...)
 			lockCtx.Stats.Mu.Unlock()
 		}
-		if lockCtx.Killed != nil {
-			// If the kill signal is received during waiting for pessimisticLock,
-			// pessimisticLockKeys would handle the error but it doesn't reset the flag.
-			// We need to reset the killed flag here.
-			atomic.CompareAndSwapUint32(lockCtx.Killed, 1, 0)
-		}
 		if txn.IsInAggressiveLockingMode() {
 			if txn.aggressiveLockingContext.maxLockedWithConflictTS < lockCtx.MaxLockedWithConflictTS {
 				txn.aggressiveLockingContext.maxLockedWithConflictTS = lockCtx.MaxLockedWithConflictTS