sc_mutex.cc

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/*
 * Copyright 2018 Google, Inc.
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 * this software without specific prior written permission.
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#include "systemc/core/scheduler.hh"
#include "systemc/ext/channel/sc_mutex.hh"
#include "systemc/ext/core/sc_module.hh" // for sc_gen_unique_name
 
namespace sc_core
{
 
sc_mutex::sc_mutex() : sc_interface(), sc_mutex_if(),
        sc_object(sc_gen_unique_name("mutex"))
{}
 
sc_mutex::sc_mutex(const char *name) :
        sc_interface(), sc_mutex_if(), sc_object(name)
{}
 
int
sc_mutex::lock()
{
    while (trylock() == -1)
        wait(unlockEvent);
    return 0;
}
 
int
sc_mutex::trylock()
{
    if (holder.valid())
        return -1;
    holder = ::sc_gem5::scheduler.current();
    return 0;
}
 
int
sc_mutex::unlock()
{
    if (holder != ::sc_gem5::scheduler.current())
        return -1;
 
    holder = nullptr;
    unlockEvent.notify();
    return 0;
}
 
} // namespace sc_core