Method Start

cmd/run/engine/engine.go:290–359

Start receives and handles intercepted syscalls until all processes exit.

()

// Start receives and handles intercepted syscalls until all processes exit.
func (e *Engine) Start() {
	N := runtime.NumCPU()

	var wg sync.WaitGroup
	slog.Debug("starting parallel receive-dispatch-handle loop", "workers", N)
	defer slog.Debug("finished parallel receive-dispatch-handle loop")

	failed := make(chan *seccomp.Notif, N)
	ch := make(chan *seccomp.Notif, N)
	for i := 0; i < N; i++ {
		wg.Add(1)
		go func() {
			defer wg.Done()

			// TODO: sched_setaffinity to lock to CPU here? It'd be nice to have the
			// system call handler run on the same CPU as the tracee process that is
			// executing the system call.
			runtime.LockOSThread()
			defer runtime.UnlockOSThread()

			defer e.panicGuard(ch, failed)

			var pending *seccomp.Notif
			defer func() {
				if pending != nil {
					failed <- pending
				}
			}()

			for n := range ch {
				if n == nil {
					break
				}

				pending = n
				if e.inPanic.Load() {
					return
				}
				e.handle(n)
				pending = nil
			}
		}()
	}

dispatch:
	for e.countRunning() > 0 {
		n, errno := e.seccomp.Receive()
		switch errno {
		case 0:
			ch <- n
		case unix.ENOENT:
			// The target was killed by a signal or its syscall was interrupted by a
			// signal handler.
			continue
		case unix.EBADF:
			// The seccomp listener file descriptor was closed.
			break dispatch
		default: