NOP-In/response timeouts improvements

git-svn-id: http://svn.code.sf.net/p/scst/svn/trunk@3411 d57e44dd-8a1f-0410-8b47-8ef2f437770f

iscsi-scst/README

@@ -294,20 +294,20 @@ Each target subdirectory contains the following entries:
  - QueuedCommands - defines maximum number of commands queued to any
    session of this target. Default is 32 commands.
 
- - RspTimeout - defines the maximum time in seconds a command can wait for
-   response from initiator, otherwise the corresponding connection will
-   be closed. For performance reasons it is implemented as a timer,
-   which once in RspTimeout time checks the oldest command waiting for
-   response and, if it's older than RspTimeout, then it closes the
-   connection. Hence, a stalled connection will be closed in time
-   between RspTimeout and 2*RspTimeout. Default is 30 seconds.
-
  - NopInInterval - defines interval between NOP-In requests, which the
    target will send on idle connections to check if the initiator is
    still alive. If there is no NOP-Out reply from the initiator in
    RspTimeout time, the corresponding connection will be closed. Default
    is 30 seconds. If it's set to 0, then NOP-In requests are disabled.
 
+ - NopInTimeout - defines the maximum time in seconds a NOP-In request
+   can wait for response from initiator, otherwise the corresponding
+   connection will be closed. Default is 30 seconds.
+
+ - RspTimeout - defines the maximum time in seconds a command can wait for
+   response from initiator, otherwise the corresponding connection will
+   be closed. Default is 90 seconds.
+
  - enabled - using this attribute you can enable or disable iSCSI-SCST
    accept new connections to this target. It allows to finish
    configuring it before it starts accepting new connections. 0 by

iscsi-scst/README_in-tree

@@ -136,20 +136,20 @@ Each target subdirectory contains the following entries:
  - QueuedCommands - defines maximum number of commands queued to any
    session of this target. Default is 32 commands.
 
- - RspTimeout - defines the maximum time in seconds a command can wait for
-   response from initiator, otherwise the corresponding connection will
-   be closed. For performance reasons it is implemented as a timer,
-   which once in RspTimeout time checks the oldest command waiting for
-   response and, if it's older than RspTimeout, then it closes the
-   connection. Hence, a stalled connection will be closed in time
-   between RspTimeout and 2*RspTimeout. Default is 30 seconds.
-
  - NopInInterval - defines interval between NOP-In requests, which the
    target will send on idle connections to check if the initiator is
    still alive. If there is no NOP-Out reply from the initiator in
    RspTimeout time, the corresponding connection will be closed. Default
    is 30 seconds. If it's set to 0, then NOP-In requests are disabled.
 
+ - NopInTimeout - defines the maximum time in seconds a NOP-In request
+   can wait for response from initiator, otherwise the corresponding
+   connection will be closed. Default is 30 seconds.
+
+ - RspTimeout - defines the maximum time in seconds a command can wait for
+   response from initiator, otherwise the corresponding connection will
+   be closed. Default is 90 seconds.
+
  - enabled - using this attribute you can enable or disable iSCSI-SCST
    accept new connections to this target. It allows to finish
    configuring it before it starts accepting new connections. 0 by

iscsi-scst/include/iscsi_scst.h

@@ -70,6 +70,7 @@ enum {
 	key_queued_cmnds,
 	key_rsp_timeout,
 	key_nop_in_interval,
+	key_nop_in_timeout,
 	key_max_sessions,
 	target_key_last,
 };
@@ -187,7 +188,7 @@ struct iscsi_kern_initiator_info {
 #define	MIN_NR_QUEUED_CMNDS	1
 #define	MAX_NR_QUEUED_CMNDS	256
 
-#define DEFAULT_RSP_TIMEOUT	30
+#define DEFAULT_RSP_TIMEOUT	90
 #define MIN_RSP_TIMEOUT		2
 #define MAX_RSP_TIMEOUT		65535
 
@@ -195,6 +196,10 @@ struct iscsi_kern_initiator_info {
 #define MIN_NOP_IN_INTERVAL	0
 #define MAX_NOP_IN_INTERVAL	65535
 
+#define DEFAULT_NOP_IN_TIMEOUT  30
+#define MIN_NOP_IN_TIMEOUT	2
+#define MAX_NOP_IN_TIMEOUT	65535
+
 #define NETLINK_ISCSI_SCST	25
 
 #define REGISTER_USERD		_IOWR('s', 0, struct iscsi_kern_register_info)

iscsi-scst/kernel/conn.c

@@ -530,14 +530,14 @@ static void conn_rsp_timer_fn(unsigned long arg)
 		cmnd = list_entry(conn->write_timeout_list.next,
 				struct iscsi_cmnd, write_timeout_list_entry);
 
-		timeout_time = j + conn->rsp_timeout + ISCSI_ADD_SCHED_TIME;
+		timeout_time = j + iscsi_get_timeout(cmnd) + ISCSI_ADD_SCHED_TIME;
 
-		if (unlikely(time_after_eq(j, cmnd->write_start +
-						conn->rsp_timeout))) {
+		if (unlikely(time_after_eq(j, iscsi_get_timeout_time(cmnd)))) {
 			if (!conn->closing) {
-				PRINT_ERROR("Timeout sending data/waiting "
+				PRINT_ERROR("Timeout %ld sec sending data/waiting "
 					"for reply to/from initiator "
 					"%s (SID %llx), closing connection",
+					iscsi_get_timeout(cmnd)/HZ,
 					conn->session->initiator_name,
 					(long long unsigned int)
 						conn->session->sid);
@@ -883,8 +883,9 @@ static int iscsi_conn_alloc(struct iscsi_session *session,
 		conn);
 #endif
 	conn->last_rcv_time = jiffies;
-	conn->rsp_timeout = session->tgt_params.rsp_timeout * HZ;
+	conn->data_rsp_timeout = session->tgt_params.rsp_timeout * HZ;
 	conn->nop_in_interval = session->tgt_params.nop_in_interval * HZ;
+	conn->nop_in_timeout = session->tgt_params.nop_in_timeout * HZ;
 	if (conn->nop_in_interval > 0) {
 		TRACE_DBG("Schedule Nop-In work for conn %p", conn);
 		schedule_delayed_work(&conn->nop_in_delayed_work,

iscsi-scst/kernel/iscsi.h

@@ -63,6 +63,7 @@ struct iscsi_tgt_params {
 	int queued_cmnds;
 	unsigned int rsp_timeout;
 	unsigned int nop_in_interval;
+	unsigned int nop_in_timeout;
 };
 
 struct iscsi_thread {
@@ -213,7 +214,7 @@ struct iscsi_conn {
 
 	/* Protected by write_list_lock */
 	struct timer_list rsp_timer;
-	unsigned int rsp_timeout; /* in jiffies */
+	unsigned int data_rsp_timeout; /* in jiffies */
 
 	/*
 	 * All 2 protected by wr_lock. Modified independently to the
@@ -303,6 +304,7 @@ struct iscsi_conn {
 	struct work_struct nop_in_delayed_work;
 #endif
 	unsigned int nop_in_interval; /* in jiffies */
+	unsigned int nop_in_timeout; /* in jiffies */
 	struct list_head nop_req_list;
 	spinlock_t nop_req_list_lock;
 	u32 nop_in_ttt;
@@ -750,6 +752,17 @@ static inline void cmd_del_from_rx_ddigest_list(struct iscsi_cmnd *cmnd)
 #endif
 }
 
+static inline unsigned long iscsi_get_timeout(struct iscsi_cmnd *req)
+{
+	return (cmnd_opcode(req) == ISCSI_OP_NOP_OUT) ?
+			req->conn->nop_in_timeout : req->conn->data_rsp_timeout;
+}
+
+static inline unsigned long iscsi_get_timeout_time(struct iscsi_cmnd *req)
+{
+	return req->write_start + iscsi_get_timeout(req);
+}
+
 static inline int test_write_ready(struct iscsi_conn *conn)
 {
 	/*

iscsi-scst/kernel/nthread.c

@@ -1217,8 +1217,32 @@ void req_add_to_write_timeout_list(struct iscsi_cmnd *req)
 	req->on_write_timeout_list = 1;
 	req->write_start = jiffies;
 
-	list_add_tail(&req->write_timeout_list_entry,
-		&conn->write_timeout_list);
+	if (unlikely(cmnd_opcode(req) == ISCSI_OP_NOP_OUT)) {
+		unsigned long req_tt = iscsi_get_timeout_time(req);
+		struct iscsi_cmnd *r;
+		bool inserted = false;
+		list_for_each_entry(r, &conn->write_timeout_list,
+					write_timeout_list_entry) {
+			unsigned long tt = iscsi_get_timeout_time(r);
+			if (time_after(tt, req_tt)) {
+				TRACE_DBG("Add NOP IN req %p (tt %ld) before "
+					"req %p (tt %ld)", req, req_tt, r, tt);
+				list_add_tail(&req->write_timeout_list_entry,
+					&r->write_timeout_list_entry);
+				inserted = true;
+				break;
+			} else
+				TRACE_DBG("Skipping op %x req %p (tt %ld)",
+					cmnd_opcode(r), r, tt);
+		}
+		if (!inserted) {
+			TRACE_DBG("Add NOP IN req %p in the tail", req);
+			list_add_tail(&req->write_timeout_list_entry,
+				&conn->write_timeout_list);
+		}
+	} else
+		list_add_tail(&req->write_timeout_list_entry,
+			&conn->write_timeout_list);
 
 	if (!timer_pending(&conn->rsp_timer)) {
 		unsigned long timeout_time;
@@ -1227,11 +1251,11 @@ void req_add_to_write_timeout_list(struct iscsi_cmnd *req)
 					&req->prelim_compl_flags))) {
 			set_conn_tm_active = true;
 			timeout_time = req->write_start +
-					ISCSI_TM_DATA_WAIT_TIMEOUT +
-					ISCSI_ADD_SCHED_TIME;
+					ISCSI_TM_DATA_WAIT_TIMEOUT;
 		} else
-			timeout_time = req->write_start +
-				conn->rsp_timeout + ISCSI_ADD_SCHED_TIME;
+			timeout_time = iscsi_get_timeout_time(req);
+
+		timeout_time += ISCSI_ADD_SCHED_TIME;
 
 		TRACE_DBG("Starting timer on %ld (con %p, write_start %ld)",
 			timeout_time, conn, req->write_start);

iscsi-scst/kernel/param.c

@@ -204,6 +204,8 @@ static void tgt_params_check(struct iscsi_session *session,
 		MAX_RSP_TIMEOUT);
 	CHECK_PARAM(info, iparams, nop_in_interval, MIN_NOP_IN_INTERVAL,
 		MAX_NOP_IN_INTERVAL);
+	CHECK_PARAM(info, iparams, nop_in_timeout, MIN_NOP_IN_TIMEOUT,
+		MAX_NOP_IN_TIMEOUT);
 	return;
 }
 
@@ -222,16 +224,19 @@ static int iscsi_tgt_params_set(struct iscsi_session *session,
 		SET_PARAM(params, info, iparams, queued_cmnds);
 		SET_PARAM(params, info, iparams, rsp_timeout);
 		SET_PARAM(params, info, iparams, nop_in_interval);
+		SET_PARAM(params, info, iparams, nop_in_timeout);
 
 		PRINT_INFO("Target parameters set for session %llx: "
 			"QueuedCommands %d, Response timeout %d, Nop-In "
-			"interval %d", session->sid, params->queued_cmnds,
-			params->rsp_timeout, params->nop_in_interval);
+			"interval %d, Nop-In timeout %d", session->sid,
+			params->queued_cmnds, params->rsp_timeout,
+			params->nop_in_interval, params->nop_in_timeout);
 
 		list_for_each_entry(conn, &session->conn_list,
 					conn_list_entry) {
-			conn->rsp_timeout = session->tgt_params.rsp_timeout * HZ;
+			conn->data_rsp_timeout = session->tgt_params.rsp_timeout * HZ;
 			conn->nop_in_interval = session->tgt_params.nop_in_interval * HZ;
+			conn->nop_in_timeout = session->tgt_params.nop_in_timeout * HZ;
 			spin_lock_bh(&conn->conn_thr_pool->rd_lock);
 			if (!conn->closing && (conn->nop_in_interval > 0)) {
 				TRACE_DBG("Schedule Nop-In work for conn %p", conn);
@@ -244,6 +249,7 @@ static int iscsi_tgt_params_set(struct iscsi_session *session,
 		GET_PARAM(params, info, iparams, queued_cmnds);
 		GET_PARAM(params, info, iparams, rsp_timeout);
 		GET_PARAM(params, info, iparams, nop_in_interval);
+		GET_PARAM(params, info, iparams, nop_in_timeout);
 	}
 
 	return 0;

iscsi-scst/usr/param.c

@@ -350,6 +350,7 @@ struct iscsi_key target_keys[] = {
 	{"QueuedCommands", SET_KEY_VALUES(NR_QUEUED_CMNDS), 1, &minimum_ops},
 	{"RspTimeout", SET_KEY_VALUES(RSP_TIMEOUT), 1, &minimum_ops},
 	{"NopInInterval", SET_KEY_VALUES(NOP_IN_INTERVAL), 1, &minimum_ops},
+	{"NopInTimeout", SET_KEY_VALUES(NOP_IN_TIMEOUT), 1, &minimum_ops},
 	{"MaxSessions", 0, 0, 0, 65535, 1, &minimum_ops},
 	{NULL,},
 };