add ticketlock test for wait-free (failed, as expected)

[userspace-rcu.git] / ticketlock-testwait / refcount.spin.input

diff --git a/ticketlock-testwait/refcount.spin.input b/ticketlock-testwait/refcount.spin.input
new file mode 100644 (file)
index 0000000..d2a22d2
--- /dev/null
+++ b/ticketlock-testwait/refcount.spin.input
@@ -0,0 +1,114 @@
+#define refcount_gt_one (refcount > 1)
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Copyright (c) 2009 Mathieu Desnoyers
+ */
+
+/* 16 CPUs max (byte has 8 bits, divided in two) */
+
+#ifndef CONFIG_BITS_PER_BYTE
+#define BITS_PER_BYTE          8
+#else
+#define BITS_PER_BYTE          CONFIG_BITS_PER_BYTE
+#endif
+
+#define HBPB                   (BITS_PER_BYTE / 2)     /* 4 */
+#define HMASK                  ((1 << HBPB) - 1)       /* 0x0F */
+
+/* for byte type */
+#define LOW_HALF(val)          ((val) & HMASK)
+#define LOW_HALF_INC           1
+
+#define HIGH_HALF(val)         ((val) & (HMASK << HBPB))
+#define HIGH_HALF_INC          (1 << HBPB)
+
+byte lock = 0;
+byte refcount = 0;
+
+#define need_pause()   (_pid == 1)
+
+/*
+ * Test weak fairness by either not pausing or cycling for any number of
+ * steps, or forever.
+ * Models a slow thread. Should be added between each atomic steps.
+ * To test for wait-freedom (no starvation of a specific thread), add do_pause
+ * in threads other than the one we are checking for progress (and which
+ * contains the progress label).
+ * To test for lock-freedom (system-wide progress), add to all threads except
+ * one. All threads contain progress labels.
+ */
+inline do_pause()
+{
+       if
+       :: need_pause() ->
+               do
+               :: 1 ->
+                       if
+                       :: 1 -> skip;
+                       :: 1 -> break;
+                       fi;
+               od;
+       :: else ->
+               skip;
+       fi;
+}
+
+inline spin_lock(lock, ticket)
+{
+       atomic {
+               ticket = HIGH_HALF(lock) >> HBPB;
+               lock = lock + HIGH_HALF_INC;    /* overflow expected */
+       }
+
+       do
+       :: 1 ->
+               if
+               :: (LOW_HALF(lock) == ticket) ->
+                       break;
+               :: else ->
+                       skip;
+               fi;
+       od;
+}
+
+inline spin_unlock(lock)
+{
+       lock = HIGH_HALF(lock) | LOW_HALF(lock + LOW_HALF_INC);
+}
+
+proctype proc_X()
+{
+       byte ticket;
+
+       do
+       :: 1->
+               spin_lock(lock, ticket);
+progress:
+               refcount = refcount + 1;
+               do_pause();
+               refcount = refcount - 1;
+               spin_unlock(lock);
+       od;
+}
+
+init
+{
+       run proc_X();
+       run proc_X();
+       //run proc_X();
+       //run proc_X();
+       //run proc_X();
+}