//
//	func semacreate(mp *m)
//		Create a semaphore for mp, if it does not already have one.
//
//	func semasleep(ns int64) int32
//		If ns < 0, acquire m's semaphore and return 0.
//		If ns >= 0, try to acquire m's semaphore for at most ns nanoseconds.
//		Return 0 if the semaphore was acquired, -1 if interrupted or timed out.
//
//	func semawakeup(mp *m)
//		Wake up mp, which is or will soon be sleeping on its semaphore.

			t.Fatalf("expected 3 mounts, got %d", len(mounts))
		}
		mp := mountInfo{"/dev/0", "/path/to/0", "type0", []string{"flags"}, "0", "0"}
		if !mountPointsEqual(mounts[0], mp) {
			t.Errorf("got unexpected MountPoint[0]: %#v", mounts[0])
		}
		mp = mountInfo{"/dev/1", "/path/to/1", "type1", []string{"flags"}, "1", "1"}
		if !mountPointsEqual(mounts[1], mp) {
			t.Errorf("got unexpected mountInfo[1]: %#v", mounts[1])
		}

// a non-zero byte to w, WaitForSigusr1 returns immediately with -1, -1.
func WaitForSigusr1(r, w int32, ready func(mp *M)) (int64, int64) {
	lockOSThread()
	// Make sure we can receive SIGUSR1.
	unblocksig(_SIGUSR1)

	waitForSigusr1.rdpipe = r
	waitForSigusr1.wrpipe = w

	mp := getg().m
	testSigusr1 = waitForSigusr1Callback
	ready(mp)

	// Wait for the signal. We use a pipe rather than a note
	// because write is always async-signal-safe.

		id := scheduleTimeoutEvent(delay)
		mp := acquirem()
		notes[n] = gp
		notesWithTimeout[n] = noteWithTimeout{gp: gp, deadline: deadline}
		releasem(mp)

		gopark(nil, nil, waitReasonSleep, traceBlockSleep, 1)

		clearTimeoutEvent(id) // note might have woken early, clear timeout

		mp = acquirem()
		delete(notes, n)
		delete(notesWithTimeout, n)
		releasem(mp)

		return n.key == note_woken
	}

		panic(fmt.Sprintf("unexpected f2 size == %d, want %d", got, want))
	}

	type mypair struct {
		f1 int32
		f2 int64
	}
	mp := mypair(p)
	if mp.f1 != 1 || mp.f2 != 2 {
		panic(fmt.Sprintf("mp == %#v, want %#v", mp, mypair{1, 2}))
	}

	return traceWriter{traceLocker: traceLocker{gen: gen}, traceBuf: buf}
}

// end writes the buffer back into the m.
func (w traceWriter) end() {
	if w.mp == nil {
		// Tolerate a nil mp. It makes code that creates traceWriters directly
		// less error-prone.
		return
	}
	w.mp.trace.buf[w.gen%2] = w.traceBuf
}

// ensure makes sure that at least maxSize bytes are available to write.
//
// Returns whether the buffer was flushed.

	mp := getg().m
	c := &mp.chacha8
	for {
		// Note: c.Next is marked nosplit,
		// so we don't need to use mp.locks
		// on the fast path, which is that the
		// first attempt succeeds.
		x, ok := c.Next()
		if ok {
			return x
		}
		mp.locks++ // hold m even though c.Refill may do stack split checks
		c.Refill()
		mp.locks--
	}
}

	onlyOnce sync.Once
}

func (f *leaderMetricsFactory) setProvider(mp MetricsProvider) {
	f.onlyOnce.Do(func() {
		f.metricsProvider = mp
	})
}

func (f *leaderMetricsFactory) newLeaderMetrics() leaderMetricsAdapter {
	mp := f.metricsProvider
	if mp == (noopMetricsProvider{}) {
		return noMetrics{}
	}
	return &defaultLeaderMetrics{
		leader: mp.NewLeaderMetric(),
	}
}

	"unsafe"
)

func lwp_mcontext_init(mc *mcontextt, stk unsafe.Pointer, mp *m, gp *g, fn uintptr) {
	// Machine dependent mcontext initialisation for LWP.
	mc.__gregs[_REG_ELR] = uint64(abi.FuncPCABI0(lwp_tramp))
	mc.__gregs[_REG_X31] = uint64(uintptr(stk))
	mc.__gregs[_REG_X0] = uint64(uintptr(unsafe.Pointer(mp)))
	mc.__gregs[_REG_X1] = uint64(uintptr(unsafe.Pointer(mp.g0)))
	mc.__gregs[_REG_X2] = uint64(fn)
}

//go:nosplit

// profiling buffer. It is called from a signal handler, so is limited in what
// it can do. mp must be the thread that is currently stopped in a signal.
func traceCPUSample(gp *g, mp *m, pp *p, stk []uintptr) {
	if !traceEnabled() {
		// Tracing is usually turned off; don't spend time acquiring the signal
		// lock unless it's active.
		return
	}
	if mp == nil {
		// Drop samples that don't have an identifiable thread. We can't render