error_code sys_lwmutex_trylock(ppu_thread& ppu, vm::ptr<sys_lwmutex_t> lwmutex)
{
sysPrxForUser.trace("sys_lwmutex_trylock(lwmutex=*0x%x)", lwmutex);
if (g_cfg.core.hle_lwmutex)
{
return sys_mutex_trylock(ppu, lwmutex->sleep_queue);
}
const be_t<u32> tid(ppu.id);
// try to lock lightweight mutex
const be_t<u32> old_owner = lwmutex->vars.owner.compare_and_swap(lwmutex_free, tid);
if (old_owner == lwmutex_free)
{
// locking succeeded
return CELL_OK;
}
if (old_owner == tid)
{
// recursive locking
if ((lwmutex->attribute & SYS_SYNC_RECURSIVE) == 0)
{
// if not recursive
return CELL_EDEADLK;
}
if (lwmutex->recursive_count == -1)
{
// if recursion limit reached
return CELL_EKRESOURCE;
}
// recursive locking succeeded
lwmutex->recursive_count++;
_mm_mfence();
return CELL_OK;
}
if (old_owner == lwmutex_dead)
{
// invalid or deleted mutex
return CELL_EINVAL;
}
if (old_owner == lwmutex_reserved)
{
// should be locked by the syscall
const error_code res = _sys_lwmutex_trylock(lwmutex->sleep_queue);
if (res == CELL_OK)
{
// locking succeeded
auto old = lwmutex->vars.owner.exchange(tid);
if (old != lwmutex_reserved)
{
fmt::throw_exception("Locking failed (lwmutex=*0x%x, owner=0x%x)" HERE, lwmutex, old);
}
}
return res;
}
// locked by another thread
return not_an_error(CELL_EBUSY);
}
s32 sys_lwmutex_trylock(PPUThread& CPU, vm::ptr<sys_lwmutex_t> lwmutex)
{
sysPrxForUser.Log("sys_lwmutex_trylock(lwmutex=*0x%x)", lwmutex);
const be_t<u32> tid = be_t<u32>::make(CPU.GetId());
// try to lock lightweight mutex
const be_t<u32> old_owner = lwmutex->owner.compare_and_swap(lwmutex::free, tid);
if (old_owner.data() == se32(lwmutex_free))
{
// locking succeeded
return CELL_OK;
}
if (old_owner.data() == tid.data())
{
// recursive locking
if ((lwmutex->attribute.data() & se32(SYS_SYNC_RECURSIVE)) == 0)
{
// if not recursive
return CELL_EDEADLK;
}
if (lwmutex->recursive_count.data() == -1)
{
// if recursion limit reached
return CELL_EKRESOURCE;
}
// recursive locking succeeded
lwmutex->recursive_count++;
lwmutex->lock_var.read_sync();
return CELL_OK;
}
if (old_owner.data() == se32(lwmutex_dead))
{
// invalid or deleted mutex
return CELL_EINVAL;
}
if (old_owner.data() == se32(lwmutex_reserved))
{
// should be locked by the syscall
const s32 res = _sys_lwmutex_trylock(lwmutex->sleep_queue);
if (res == CELL_OK)
{
// locking succeeded
auto old = lwmutex->owner.exchange(tid);
if (old.data() != se32(lwmutex_reserved) && !Emu.IsStopped())
{
sysPrxForUser.Fatal("sys_lwmutex_trylock(lwmutex=*0x%x): locking failed (owner=0x%x)", lwmutex, old);
}
}
return res;
}
// locked by another thread
return CELL_EBUSY;
}