trace = traceAcquire()
	}

	// mp.curg is now a real goroutine.
	casgstatus(mp.curg, _Gdead, _Gsyscall)
	sched.ngsys.Add(-1)

	if !signal {
		if trace.ok() {
			trace.GoCreateSyscall(mp.curg)
			traceRelease(trace)
		}
	}
	mp.isExtraInSig = signal
}

// Acquire an extra m and bind it to the C thread when a pthread key has been created.
//
//go:nosplit