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Diffstat (limited to '063wait.cc')
| -rw-r--r-- | 063wait.cc | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/063wait.cc b/063wait.cc new file mode 100644 index 00000000..ef3d30e5 --- /dev/null +++ b/063wait.cc @@ -0,0 +1,167 @@ +//: Routines can be put in a 'waiting' state, from which it will be ready to +//: run again when a specific memory location changes its value. This is mu's +//: basic technique for orchestrating the order in which different routines +//: operate. + +:(scenario wait_for_location) +recipe f1 [ + 1:number <- copy 0 + start-running f2:recipe + wait-for-location 1:number + # now wait for f2 to run and modify location 1 before using its value + 2:number <- copy 1:number +] +recipe f2 [ + 1:number <- copy 34 +] +# if we got the synchronization wrong we'd be storing 0 in location 2 ++mem: storing 34 in location 2 + +//: define the new state that all routines can be in + +:(before "End routine States") +WAITING, +:(before "End routine Fields") +// only if state == WAITING +long long int waiting_on_location; +int old_value_of_waiting_location; +:(before "End routine Constructor") +waiting_on_location = old_value_of_waiting_location = 0; + +//: primitive recipe to put routines in that state + +:(before "End Primitive Recipe Declarations") +WAIT_FOR_LOCATION, +:(before "End Primitive Recipe Numbers") +put(Recipe_ordinal, "wait-for-location", WAIT_FOR_LOCATION); +:(before "End Primitive Recipe Checks") +case WAIT_FOR_LOCATION: { + break; +} +:(before "End Primitive Recipe Implementations") +case WAIT_FOR_LOCATION: { + reagent loc = current_instruction().ingredients.at(0); + canonize(loc); + Current_routine->state = WAITING; + Current_routine->waiting_on_location = loc.value; + Current_routine->old_value_of_waiting_location = get_or_insert(Memory, loc.value); + trace(9998, "run") << "waiting for location " << loc.value << " to change from " << no_scientific(get_or_insert(Memory, loc.value)) << end(); + break; +} + +//: scheduler tweak to get routines out of that state + +:(before "End Scheduler State Transitions") +for (long long int i = 0; i < SIZE(Routines); ++i) { + if (Routines.at(i)->state != WAITING) continue; + if (Routines.at(i)->waiting_on_location && + get_or_insert(Memory, Routines.at(i)->waiting_on_location) != Routines.at(i)->old_value_of_waiting_location) { + trace(9999, "schedule") << "waking up routine\n" << end(); + Routines.at(i)->state = RUNNING; + Routines.at(i)->waiting_on_location = Routines.at(i)->old_value_of_waiting_location = 0; + } +} + +//: also allow waiting on a routine to stop running + +:(scenario wait_for_routine) +recipe f1 [ + 1:number <- copy 0 + 12:number/routine <- start-running f2:recipe + wait-for-routine 12:number/routine + # now wait for f2 to run and modify location 1 before using its value + 3:number <- copy 1:number +] +recipe f2 [ + 1:number <- copy 34 +] ++schedule: f1 ++run: waiting for routine 2 ++schedule: f2 ++schedule: waking up routine 1 ++schedule: f1 +# if we got the synchronization wrong we'd be storing 0 in location 3 ++mem: storing 34 in location 3 + +:(before "End routine Fields") +// only if state == WAITING +long long int waiting_on_routine; +:(before "End routine Constructor") +waiting_on_routine = 0; + +:(before "End Primitive Recipe Declarations") +WAIT_FOR_ROUTINE, +:(before "End Primitive Recipe Numbers") +put(Recipe_ordinal, "wait-for-routine", WAIT_FOR_ROUTINE); +:(before "End Primitive Recipe Checks") +case WAIT_FOR_ROUTINE: { + if (SIZE(inst.ingredients) != 1) { + raise_error << maybe(get(Recipe, r).name) << "'wait-for-routine' requires exactly one ingredient, but got " << inst.to_string() << '\n' << end(); + break; + } + if (!is_mu_number(inst.ingredients.at(0))) { + raise_error << maybe(get(Recipe, r).name) << "first ingredient of 'wait-for-routine' should be a routine id generated by 'start-running', but got " << inst.ingredients.at(0).original_string << '\n' << end(); + break; + } + break; +} +:(before "End Primitive Recipe Implementations") +case WAIT_FOR_ROUTINE: { + if (ingredients.at(0).at(0) == Current_routine->id) { + raise_error << maybe(current_recipe_name()) << "routine can't wait for itself! " << current_instruction().to_string() << '\n' << end(); + break; + } + Current_routine->state = WAITING; + Current_routine->waiting_on_routine = ingredients.at(0).at(0); + trace(9998, "run") << "waiting for routine " << ingredients.at(0).at(0) << end(); + break; +} + +:(before "End Scheduler State Transitions") +// Wake up any routines waiting for other routines to go to sleep. +// Important: this must come after the scheduler loop above giving routines +// waiting for locations to change a chance to wake up. +for (long long int i = 0; i < SIZE(Routines); ++i) { + if (Routines.at(i)->state != WAITING) continue; + if (!Routines.at(i)->waiting_on_routine) continue; + long long int id = Routines.at(i)->waiting_on_routine; + assert(id != Routines.at(i)->id); // routine can't wait on itself + for (long long int j = 0; j < SIZE(Routines); ++j) { + if (Routines.at(j)->id == id && Routines.at(j)->state != RUNNING) { + trace(9999, "schedule") << "waking up routine " << Routines.at(i)->id << end(); + Routines.at(i)->state = RUNNING; + Routines.at(i)->waiting_on_routine = 0; + } + } +} + +:(before "End Primitive Recipe Declarations") +SWITCH, +:(before "End Primitive Recipe Numbers") +put(Recipe_ordinal, "switch", SWITCH); +:(before "End Primitive Recipe Checks") +case SWITCH: { + break; +} +:(before "End Primitive Recipe Implementations") +case SWITCH: { + long long int id = some_other_running_routine(); + if (id) { + assert(id != Current_routine->id); + Current_routine->state = WAITING; + Current_routine->waiting_on_routine = id; + } + break; +} + +:(code) +long long int some_other_running_routine() { + for (long long int i = 0; i < SIZE(Routines); ++i) { + if (i == Current_routine_index) continue; + assert(Routines.at(i) != Current_routine); + assert(Routines.at(i)->id != Current_routine->id); + if (Routines.at(i)->state == RUNNING) + return Routines.at(i)->id; + } + return 0; +} |