From: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Date: Sat, 26 Sep 2009 12:19:26 +0000 (-0400)
Subject: Add multiple reader queues to futex model
X-Git-Tag: v0.1~26
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=29f38067765e2d60bbf9bebcf6b7d3084b8bdec0;p=userspace-rcu.git

Add multiple reader queues to futex model

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
---

diff --git a/formal-model/futex-wakeup/DEFINES b/formal-model/futex-wakeup/DEFINES
index 7c9a54f..e328b55 100644
--- a/formal-model/futex-wakeup/DEFINES
+++ b/formal-model/futex-wakeup/DEFINES
@@ -1 +1 @@
-#define queue_has_entry	(queue == 1)
+#define queue_has_entry	(queue[0] == 1 || queue[1] == 1)
diff --git a/formal-model/futex-wakeup/futex.spin b/formal-model/futex-wakeup/futex.spin
index 1cb6442..5459a53 100644
--- a/formal-model/futex-wakeup/futex.spin
+++ b/formal-model/futex-wakeup/futex.spin
@@ -46,12 +46,16 @@
  * Copyright (c) 2009 Mathieu Desnoyers
  */
 
-int queue = 0;
+#define get_pid()       (_pid)
+
+int queue[2] = 0;
 int fut = 0;
 
-active proctype waker()
+active [2] proctype waker()
 {
-	queue = 1;
+	assert(get_pid() < 2);
+
+	queue[get_pid()] = 1;
 
 	if
 	:: (fut == -1) ->
@@ -60,7 +64,7 @@ active proctype waker()
 		skip;
 	fi;
 
-	queue = 1;
+	queue[get_pid()] = 1;
 
 	if
 	:: (fut == -1) ->
@@ -70,7 +74,7 @@ active proctype waker()
 	fi;
 
 #ifdef INJ_QUEUE_NO_WAKE
-	queue = 1;
+	queue[get_pid()] = 1;
 #endif
 }
 
@@ -83,7 +87,7 @@ active proctype waiter()
 		fut = fut - 1;
 #endif
 		if
-		:: (queue == 1) ->
+		:: (queue[0] == 1 || queue[1] == 1) ->
 #ifndef INJ_LATE_DEC
 			fut = 0;
 #endif
@@ -108,6 +112,13 @@ active proctype waiter()
 			fi;
 		fi;
 progress:
-		queue = 0;
+		if
+		:: queue[0] == 1 ->
+			queue[0] = 0;
+		fi;
+		if
+		:: queue[1] == 1 ->
+			queue[1] = 0;
+		fi;
 	od;
 }