From db2ed21438470d92ff7c75d5c4f1856798bd899b Mon Sep 17 00:00:00 2001
From: chessman <eugene@datomia.com>
Date: Fri, 28 Jun 2019 19:56:14 +0300
Subject: [PATCH] remove task from PendingTasks queue

---
 pkg/port/iscsit/iscsid.go  | 30 +++++++++++++-----------------
 pkg/port/iscsit/session.go | 26 +++++++++++++++++++++++---
 2 files changed, 36 insertions(+), 20 deletions(-)

diff --git a/pkg/port/iscsit/iscsid.go b/pkg/port/iscsit/iscsid.go
index c8cd70e..117ab04 100644
--- a/pkg/port/iscsit/iscsid.go
+++ b/pkg/port/iscsit/iscsid.go
@@ -595,7 +595,9 @@ func (s *ISCSITargetDriver) scsiCommandHandler(conn *iscsiConnection) (err error
 				// prepare to receive more data
 				conn.session.ExpCmdSN += 1
 				task.state = taskPending
+				conn.session.PendingTasksMutex.Lock()
 				conn.session.PendingTasks.Push(task)
+				conn.session.PendingTasksMutex.Unlock()
 				conn.rxTask = task
 				if conn.session.SessionParam[ISCSI_PARAM_INITIAL_R2T_EN].Value == 1 {
 					iscsiExecR2T(conn)
@@ -638,12 +640,9 @@ func (s *ISCSITargetDriver) scsiCommandHandler(conn *iscsiConnection) (err error
 		}
 	case OpSCSIOut:
 		log.Debugf("iSCSI Data-out processing...")
-		var task *iscsiTask
-		for _, t := range conn.session.PendingTasks {
-			if t.tag == conn.req.TaskTag {
-				task = t
-			}
-		}
+		conn.session.PendingTasksMutex.RLock()
+		task := conn.session.PendingTasks.GetByTag(conn.req.TaskTag)
+		conn.session.PendingTasksMutex.RUnlock()
 		if task == nil {
 			err = fmt.Errorf("Cannot find iSCSI task with tag[%v]", conn.req.TaskTag)
 			log.Error(err)
@@ -679,6 +678,9 @@ func (s *ISCSITargetDriver) scsiCommandHandler(conn *iscsiConnection) (err error
 		} else {
 			conn.buildRespPackage(OpSCSIResp, task)
 			conn.rxTask = nil
+			conn.session.PendingTasksMutex.Lock()
+			conn.session.PendingTasks.RemoveByTag(conn.req.TaskTag)
+			conn.session.PendingTasksMutex.Unlock()
 		}
 	case OpNoopOut:
 		iscsiExecNoopOut(conn)
@@ -719,11 +721,12 @@ func (s *ISCSITargetDriver) iscsiTaskQueueHandler(task *iscsiTask) error {
 		if err := s.iscsiExecTask(task); err != nil {
 			log.Error(err)
 		}
-		if len(sess.PendingTasks) == 0 {
+		sess.PendingTasksMutex.Lock()
+		if sess.PendingTasks.Len() == 0 {
+			sess.PendingTasksMutex.Unlock()
 			return nil
 		}
-		sess.PendingTasksMutex.Lock()
-		task = sess.PendingTasks.Pop().(*iscsiTask)
+		task = sess.PendingTasks.Pop()
 		cmd = task.cmd
 		if cmd.CmdSN != cmdsn {
 			sess.PendingTasks.Push(task)
@@ -770,15 +773,8 @@ func (s *ISCSITargetDriver) iscsiExecTask(task *iscsiTask) error {
 		sess := task.conn.session
 		switch cmd.TaskFunc {
 		case ISCSI_TM_FUNC_ABORT_TASK:
-			var stask *iscsiTask
 			sess.PendingTasksMutex.Lock()
-			for i, t := range sess.PendingTasks {
-				if cmd.ReferencedTaskTag == t.tag {
-					stask = sess.PendingTasks[i]
-					sess.PendingTasks = append(sess.PendingTasks[:i], sess.PendingTasks[i+1:]...)
-					break
-				}
-			}
+			stask := sess.PendingTasks.RemoveByTag(cmd.ReferencedTaskTag)
 			sess.PendingTasksMutex.Unlock()
 			if stask == nil {
 				task.result = ISCSI_TMF_RSP_NO_TASK
diff --git a/pkg/port/iscsit/session.go b/pkg/port/iscsit/session.go
index 9dab09f..4c74463 100644
--- a/pkg/port/iscsit/session.go
+++ b/pkg/port/iscsit/session.go
@@ -273,12 +273,12 @@ func (tq taskQueue) Swap(i, j int) {
 	tq[i], tq[j] = tq[j], tq[i]
 }
 
-func (tq *taskQueue) Push(x interface{}) {
-	item := x.(*iscsiTask)
+func (tq *taskQueue) Push(x *iscsiTask) {
+	item := x
 	*tq = append(*tq, item)
 }
 
-func (tq *taskQueue) Pop() interface{} {
+func (tq *taskQueue) Pop() *iscsiTask {
 	old := *tq
 	n := len(old)
 	item := old[n-1]
@@ -286,6 +286,26 @@ func (tq *taskQueue) Pop() interface{} {
 	return item
 }
 
+func (tq taskQueue) GetByTag(tag uint32) *iscsiTask {
+	for _, t := range tq {
+		if t.tag == tag {
+			return t
+		}
+	}
+	return nil
+}
+
+func (tq *taskQueue) RemoveByTag(tag uint32) *iscsiTask {
+	old := *tq
+	for i, t := range old {
+		if t.tag == tag {
+			*tq = append(old[:i], old[i+1:]...)
+			return t
+		}
+	}
+	return nil
+}
+
 func (s *ISCSITargetDriver) LookupISCSISession(tgtName string, iniName string, isid uint64, tsih uint16, tpgt uint16) *ISCSISession {
 	var (
 		tgt  *ISCSITarget