--- /dev/null
+# 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) Mathieu Desnoyers, 2009
+#
+# Authors: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
+
+#CFLAGS=-DSAFETY
+#CFLAGS=-DHASH64 -DREACH
+CFLAGS=-DHASH64
+
+#try pan -i to get the smallest trace.
+
+SPINFILE=futex.spin
+SPINFILE_FAIR=futex.spin
+
+default:
+ make futex_progress | tee futex_progress.log
+ make futex_progress_no_wake | tee futex_progress_no_wake.log
+ make futex_progress_late_dec | tee futex_progress_late_dec.log
+ make asserts | tee asserts.log
+ make summary
+
+#show trail : spin -v -t -N pan.ltl input.spin
+# after each individual make.
+
+summary:
+ @echo
+ @echo "Verification summary"
+ @grep error *.log
+
+asserts: clean
+ cat DEFINES > .input.spin
+ cat ${SPINFILE} >> .input.spin
+ rm -f .input.spin.trail
+ spin -a -X .input.spin
+ gcc -w ${CFLAGS} -DSAFETY -o pan pan.c
+ ./pan -v -c1 -X -m10000000 -w19
+ cp .input.spin $@.spin.input
+ -cp .input.spin.trail $@.spin.input.trail
+
+futex_progress: clean futex_ltl run_weak_fair
+ cp .input.spin $@.spin.input
+ -cp .input.spin.trail $@.spin.input.trail
+
+futex_progress_no_wake: clean futex_ltl futex_progress_no_wake_define run_weak_fair
+ cp .input.spin $@.spin.input
+ -cp .input.spin.trail $@.spin.input.trail
+
+futex_progress_no_wake_define:
+ cp futex_progress_no_wake.define .input.define
+
+futex_progress_late_dec: clean futex_ltl futex_progress_late_dec_define run_weak_fair
+ cp .input.spin $@.spin.input
+ -cp .input.spin.trail $@.spin.input.trail
+
+futex_progress_late_dec_define:
+ cp futex_progress_late_dec.define .input.define
+
+futex_ltl:
+ touch .input.define
+ cat DEFINES > pan.ltl
+ cat .input.define >> pan.ltl
+ spin -f "!(`cat futex.ltl | grep -v ^//`)" >> pan.ltl
+
+run: pan
+ ./pan -a -v -c1 -X -m10000000 -w19
+
+pan: pan.c
+ gcc -w ${CFLAGS} -o pan pan.c
+
+pan.c: pan.ltl ${SPINFILE}
+ cat DEFINES > .input.spin
+ cat .input.define >> .input.spin
+ cat ${SPINFILE} >> .input.spin
+ rm -f .input.spin.trail
+ spin -a -X -N pan.ltl .input.spin
+
+run_weak_fair: pan_fair
+ ./pan_fair -a -f -v -c1 -X -m10000000 -w20
+
+pan_fair: pan_fair.c
+ gcc -w ${CFLAGS} -o pan_fair pan_fair.c
+
+pan_fair.c: pan.ltl ${SPINFILE_FAIR}
+ cat DEFINES > .input.spin
+ cat .input.define >> .input.spin
+ cat ${SPINFILE_FAIR} >> .input.spin
+ rm -f .input.spin.trail
+ spin -a -X -N pan.ltl .input.spin
+ mv pan.c pan_fair.c
+
+.PHONY: clean default distclean summary
+clean:
+ rm -f pan* trail.out .input.spin* *.spin.trail .input.define
+distclean:
+ rm -f *.trail *.input *.log
--- /dev/null
+/*
+ * futex.spin: Promela code to validate n wakers to 1 waiter futex
+ * wakeup algorithm.
+ *
+ * In this model, waker threads unconditionally wake the waiter if it
+ * needs to be awakened. We guarantee that the waiter will never wait
+ * forever if it needs to be awakened, even if the waker is inactive
+ * after requiring the wakeup.
+ *
+ * Algorithm verified :
+ *
+ * queue = 0;
+ * futex = 0;
+ * futex_wake = 0;
+ *
+ * n wakers (2 loops)
+ *
+ * queue = 1;
+ * if (futex == -1) {
+ * futex = 0;
+ * futex_wake = 1;
+ * }
+ *
+ * 1 waiter
+ *
+ * while (1) {
+ * progress:
+ * futex = -1;
+ * if (queue == 1) {
+ * futex = 0;
+ * } else {
+ * if (futex == -1) {
+ * futex_wake = (futex == -1 ? 0 : 1); (atomic)
+ * while (futex_wake == 0) { };
+ * }
+ * queue = 0;
+ * }
+ *
+ * if queue = 1, then !_np
+ *
+ * By testing progress, i.e. [] <> ((!np_) || (!queue_has_entry)), we
+ * check that we can never block forever if there is an entry in the
+ * queue.
+ *
+ * The waker performs only 2 loops (and NOT an infinite number of loops)
+ * because we really want to see what happens when the waker stops
+ * enqueuing.
+ *
+ * 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
+ */
+
+#define get_pid() (_pid)
+
+int queue[2] = 0;
+int futex = 0;
+int futex_wake = 0;
+
+active [2] proctype waker()
+{
+ assert(get_pid() < 2);
+
+ /* loop 1 */
+ queue[get_pid()] = 1;
+
+ if
+ :: (futex == -1) ->
+ futex = 0;
+ futex_wake = 1;
+ :: else ->
+ skip;
+ fi;
+
+ /* loop 2 */
+ queue[get_pid()] = 1;
+
+ if
+ :: (futex == -1) ->
+ futex = 0;
+ futex_wake = 1;
+ :: else ->
+ skip;
+ fi;
+
+#ifdef INJ_QUEUE_NO_WAKE
+ /* loop 3 */
+ queue[get_pid()] = 1;
+#endif
+}
+
+
+active proctype waiter()
+{
+ do
+ :: 1 ->
+#ifndef INJ_LATE_DEC
+ futex = -1;
+#endif
+
+ if
+ :: (queue[0] == 1 || queue[1] == 1) ->
+#ifndef INJ_LATE_DEC
+ futex = 0;
+#endif
+ skip;
+ :: else ->
+#ifdef INJ_LATE_DEC
+ futex = -1;
+#endif
+ if
+ :: (futex == -1) ->
+ atomic {
+ if
+ :: (futex == -1) ->
+ futex_wake = 0;
+ :: else ->
+ futex_wake = 1;
+ fi;
+ }
+ /* block */
+ do
+ :: 1 ->
+ if
+ :: (futex_wake == 0) ->
+ skip;
+ :: else ->
+ break;
+ fi;
+ od;
+ :: else ->
+ skip;
+ fi;
+ fi;
+progress: /* Progress on dequeue */
+ queue[0] = 0;
+ queue[1] = 0;
+ od;
+
+}
projects / urcu.git / commitdiff
