From: Vincent Hanquez <vincent.hanquez@eu.citrix.com>
Date: Wed, 12 Aug 2009 12:53:33 +0000 (+0100)
Subject: add a main monitor thread that control the quit functionality.
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=18d9ad10f079a3f6f9355a3bdab241cc964b948e;p=xenclient%2Ftoolstack.git

add a main monitor thread that control the quit functionality.

also add the skeleton for starting a dbus monitor where to receive RPCs.
---

diff --git a/xenvm/vmstate.ml b/xenvm/vmstate.ml
index 9af2ca7..1283c2b 100644
--- a/xenvm/vmstate.ml
+++ b/xenvm/vmstate.ml
@@ -39,8 +39,19 @@ type locks = {
 	l_start: Mutex.t;
 }
 
+type monitor_state = {
+	monitor_use_dbus: bool;
+	monitor_use_json: bool;
+	mutable monitor_json_quit: bool;
+	mutable monitor_dbus_quit: bool;
+}
+
 type vm_state = {
 	vm_uuid: string;
+	vm_monitors: monitor_state;
+	quit_mutex: Mutex.t;
+	quit_condition: Condition.t;
+	mutable quit_requested: bool;
 	mutable vm_config_path: string;
 	mutable vm_arch: Domain.domarch;
 	mutable vm_domid: int;
@@ -57,6 +68,15 @@ type vm_state = {
 let state_init uuid config_path cfg =
 	{
 		vm_uuid = uuid;
+		vm_monitors = {
+			monitor_use_dbus = false;
+			monitor_use_json = true;
+			monitor_json_quit = false;
+			monitor_dbus_quit = false;
+		};
+		quit_mutex = Mutex.create ();
+		quit_condition = Condition.create ();
+		quit_requested = false;
 		vm_config_path = config_path;
 		vm_arch = if cfg.hvm then Domain.Arch_HVM else Domain.Arch_native;
 		vm_domid = (-1);
diff --git a/xenvm/xenvm.ml b/xenvm/xenvm.ml
index 1ec82ba..cd4a127 100644
--- a/xenvm/xenvm.ml
+++ b/xenvm/xenvm.ml
@@ -27,6 +27,13 @@ let thread_create f x =
 	let (_: Thread.t) = Thread.create f x in
 	()
 
+let notify_quit state =
+	Mutex.lock state.quit_mutex;
+	state.quit_requested <- true;
+	Condition.signal state.quit_condition;
+	Mutex.unlock state.quit_mutex;
+	()
+
 let string_of_exn exn =
 	match exn with
 	| Hotplug.Device_timeout dev ->
@@ -393,7 +400,7 @@ let reread_config state path =
 	let cfg = Config.of_file state.vm_uuid (fun errors -> ()) path in
 	state.vm_next_cfg <- Some cfg
 
-let do_task quit state (task, args) =
+let do_task state (task, args) =
 	let optional_arg default f args s =
 		try f args s with Tasks.Argument_not_found _ -> default
 		in
@@ -405,7 +412,7 @@ let do_task quit state (task, args) =
 	(*maybe assert_vmstate task_vmstate_required;*)
 	match task with
 	| Tasks.Quit ->
-		quit := true; Xenvmlib.Ok
+		notify_quit state; Xenvmlib.Ok
 	| Tasks.Help ->
 		do_help ();
 	| Tasks.Destroy -> with_xcs (fun xc xs -> Vmact.stop_vm xc xs state); Xenvmlib.Ok
@@ -500,18 +507,11 @@ let do_task quit state (task, args) =
 		reread_config state path;
 		Xenvmlib.Ok
 
-let monitor_rpc socket state =
-	let read_config_noexn state path =
-		try reread_config state path
-		with exn ->
-			info "receive exception reading config file ignoring: %s"
-			     (string_of_exn exn)
-		in
+let monitor_rpc_json socket state =
 	let assert_vmstate expected =
 		if expected <> state.vm_lifestate then
 			raise (Vmact.Vm_bad_state (expected, state.vm_lifestate));
 		in
-	let quit = ref false in
 	let connections = ref [] in
 
 	let reply_error con error =
@@ -538,7 +538,7 @@ let monitor_rpc socket state =
 			let reply_id = match rpc.Jsonrpc.request_id with Some id -> id | None -> Json.Int 0L in
 			let reply =
 				try
-					let r = do_task quit state (task, params) in
+					let r = do_task state (task, params) in
 					match r with
 					| Xenvmlib.Ok -> Jsonrpc.response_make_success reply_id Json.Null
 					| Xenvmlib.Msg msg -> Jsonrpc.response_make_success reply_id (Json.String msg)
@@ -614,10 +614,7 @@ let monitor_rpc socket state =
 		)
 		in
 
-	Sys.set_signal Sys.sigint (Sys.Signal_handle (fun i -> quit := true));
-	Sys.set_signal Sys.sighup (Sys.Signal_handle (fun i -> read_config_noexn state None));
-
-	while not !quit
+	while not state.vm_monitors.monitor_json_quit
 	do
 		let has_work = List.fold_left (fun acc con -> acc || con_has_work con) false !connections in
 		let timeout = if has_work then 0. else 1. in
@@ -651,6 +648,9 @@ let monitor_rpc socket state =
 		)
 	)
 
+let monitor_rpc_dbus state =
+	()
+
 (*
  * Monitor is in charge of 2 things: listen to VM requests, and listen to user queries.
  * - vm requests are: spontaneous shutdown and reboot
@@ -658,7 +658,28 @@ let monitor_rpc socket state =
  *)
 let monitor socket state =
 	thread_create monitor_vm state;
-	monitor_rpc socket state
+	if state.vm_monitors.monitor_use_json then
+		thread_create (monitor_rpc_json socket) state;
+	if state.vm_monitors.monitor_use_dbus then
+		thread_create monitor_rpc_dbus state;
+
+	let read_config_noexn state path =
+		try reread_config state path
+		with exn ->
+			info "receive exception reading config file ignoring: %s"
+			     (string_of_exn exn)
+		in
+
+	Sys.set_signal Sys.sigint (Sys.Signal_handle (fun i -> notify_quit state));
+	Sys.set_signal Sys.sighup (Sys.Signal_handle (fun i -> read_config_noexn state None));
+
+	Mutex.lock state.quit_mutex;
+	while not state.quit_requested do
+		Condition.wait state.quit_condition state.quit_mutex;
+	done;
+	Mutex.unlock state.quit_mutex;
+	Thread.delay 0.5; (* give time for others threads to finish what they are doing .. *)
+	exit 0
 
 (*********
 let do_snapshot .. =