1 /* Copyright (c) 2019-2022. The SimGrid Team. All rights reserved. */
3 /* This program is free software; you can redistribute it and/or modify it
4 * under the terms of the license (GNU LGPL) which comes with this package. */
6 #ifndef SIMGRID_MC_SIMCALL_OBSERVER_HPP
7 #define SIMGRID_MC_SIMCALL_OBSERVER_HPP
9 #include "simgrid/forward.h"
10 #include "src/mc/transition/Transition.hpp"
11 #include "xbt/asserts.h"
19 class SimcallObserver {
20 ActorImpl* const issuer_;
23 explicit SimcallObserver(ActorImpl* issuer) : issuer_(issuer) {}
24 ActorImpl* get_issuer() const { return issuer_; }
25 /** Whether this transition can currently be taken without blocking.
27 * For example, a mutex_lock is not enabled when the mutex is not free.
28 * A comm_receive is not enabled before the corresponding send has been issued.
30 virtual bool is_enabled() { return true; }
32 /** Returns the amount of time that this transition can be used.
34 * If it's 0, the transition is not enabled.
35 * If it's 1 (as with send/wait), there is no need to fork the state space exploration on this point.
36 * If it's more than one (as with mc_random or waitany), we need to consider this transition several times to start
39 virtual int get_max_consider() { return 1; }
41 /** Prepares the simcall to be used.
43 * For most simcalls, this does nothing. Once enabled, there is nothing to do to prepare a send().
45 * It is useful only for the simcalls that can be used several times, such as waitany() or random().
46 * For them, prepare() selects the right outcome for the time being considered.
48 * The first time a simcall is considered, times_considered is 0, not 1.
50 virtual void prepare(int times_considered)
51 { /* Nothing to do by default */
54 /** Computes the dependency relation */
55 virtual bool depends(SimcallObserver* other);
57 /** Serialize to the given string buffer */
58 virtual void serialize(std::stringstream& stream) const;
60 /** Some simcalls may only be observable under some conditions.
61 * Most simcalls are not visible from the MC because they don't have an observer at all. */
62 virtual bool is_visible() const { return true; }
65 template <class T> class ResultingSimcall : public SimcallObserver {
69 ResultingSimcall() = default;
70 ResultingSimcall(ActorImpl* actor, T default_result) : SimcallObserver(actor), result_(default_result) {}
71 void set_result(T res) { result_ = res; }
72 T get_result() const { return result_; }
75 class RandomSimcall : public SimcallObserver {
81 RandomSimcall(ActorImpl* actor, int min, int max) : SimcallObserver(actor), min_(min), max_(max)
83 xbt_assert(min < max);
85 void serialize(std::stringstream& stream) const override;
86 int get_max_consider() override;
87 void prepare(int times_considered) override;
88 int get_value() const { return next_value_; }
89 bool depends(SimcallObserver* other) override;
92 class ConditionWaitSimcall : public ResultingSimcall<bool> {
93 activity::ConditionVariableImpl* const cond_;
94 activity::MutexImpl* const mutex_;
95 const double timeout_;
98 ConditionWaitSimcall(ActorImpl* actor, activity::ConditionVariableImpl* cond, activity::MutexImpl* mutex,
99 double timeout = -1.0)
100 : ResultingSimcall(actor, false), cond_(cond), mutex_(mutex), timeout_(timeout)
103 bool is_enabled() override;
104 bool is_visible() const override { return false; }
105 activity::ConditionVariableImpl* get_cond() const { return cond_; }
106 activity::MutexImpl* get_mutex() const { return mutex_; }
107 double get_timeout() const { return timeout_; }
110 class SemAcquireSimcall : public ResultingSimcall<bool> {
111 activity::SemaphoreImpl* const sem_;
112 const double timeout_;
115 SemAcquireSimcall(ActorImpl* actor, activity::SemaphoreImpl* sem, double timeout = -1.0)
116 : ResultingSimcall(actor, false), sem_(sem), timeout_(timeout)
119 bool is_enabled() override;
120 bool is_visible() const override { return false; }
121 activity::SemaphoreImpl* get_sem() const { return sem_; }
122 double get_timeout() const { return timeout_; }
126 } // namespace kernel
127 } // namespace simgrid