UniTO/anno3/vpc/consegne/3/dekker_WN.smv
Francesco Mecca 9147d35cea host up
2020-05-21 13:57:43 +02:00

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MODULE main
VAR
turn: 1..2;
wantP: boolean;
wantQ: boolean;
p: process proc(turn, 1, 2, wantP, wantQ);
q: process proc(turn, 2, 1, wantQ, wantP);
ASSIGN
init(turn) := 1;
init(wantP) := FALSE;
init(wantQ) := FALSE;
CTLSPEC -- mutual exclusion
AG !(p.state = critical & q.state = critical)
CTLSPEC -- no deadlock
AG ((p.state = await | q.state = await) -> AF(p.state = critical | q.state = critical));
CTLSPEC -- no starvation
AG (p.state = await -> AF(p.state = critical));
CTLSPEC -- no starvation
AG (q.state = await -> AF(q.state = critical));
LTLSPEC -- mutual exclusion
G !(p.state = critical & q.state = critical)
LTLSPEC -- no deadlock
G ((p.state = await | q.state = await) -> F(p.state = critical | q.state = critical));
LTLSPEC -- no starvation
G (p.state = await -> F(p.state = critical));
LTLSPEC -- no starvation
G (q.state = await -> F(q.state = critical));
MODULE proc(turn, ID, otherID, mine, other)
VAR
state: {local, set_true, while, loop_set_false, await, loop_set_true, critical, switch_turn, set_false};
ASSIGN
init(state) := local;
next(state) := case
state = local: {local, set_true};
state = set_true: while;
state = while & other = FALSE: critical;
state = critical: switch_turn;
state = switch_turn: set_false;
state = set_false: local;
-- while loop
state = while & other = TRUE & turn = ID: while;
state = while & other = TRUE & turn = otherID: loop_set_false;
state = loop_set_false: await;
state = await & turn = otherID: await;
state = await & turn = ID: loop_set_true;
state = loop_set_true: while;
esac;
next(turn) := case
state = switch_turn: otherID;
TRUE: turn;
esac;
next(mine) := case -- change want{P,Q}
state = set_true: TRUE;
state = loop_set_true: TRUE;
state = set_false: FALSE;
state = loop_set_false: FALSE;
TRUE: mine;
esac;
FAIRNESS running