fix setioprio on mac

bootstrapper/internal/etcdio/etcdio.go

@@ -16,8 +16,6 @@ import (
 	"path"
 	"strconv"
 	"time"
-
-	"golang.org/x/sys/unix"
 )
 
 var (
@@ -97,7 +95,7 @@ func (c *Client) setIOPriority() error {
 	prioVal := ((targetClass & ioPrioClassMask) << ioPrioClassShift) | (targetPrio & ioPrioPrioMask)
 
 	// see https://man7.org/linux/man-pages/man2/ioprio_set.2.html
-	ret, _, errno := unix.Syscall(unix.SYS_IOPRIO_SET, ioPrioWhoProcess, uintptr(pid), uintptr(prioVal))
+	ret, _, errno := setioprio(ioPrioWhoProcess, uintptr(pid), uintptr(prioVal))
 	if ret != 0 {
 		return fmt.Errorf("setting I/O priority for etcd: %w", errno)
 	}

bootstrapper/internal/etcdio/setioprio_cross.go

@@ -0,0 +1,17 @@
+//go:build !linux
+
+/*
+Copyright (c) Edgeless Systems GmbH
+
+SPDX-License-Identifier: AGPL-3.0-only
+*/
+
+package etcdio
+
+import (
+	"syscall"
+)
+
+func setioprio(_, _, _ uintptr) (uintptr, uintptr, syscall.Errno) {
+	panic("setioprio not implemented on non-Linux platforms")
+}

bootstrapper/internal/etcdio/setioprio_linux.go

@@ -0,0 +1,19 @@
+//go:build linux
+
+/*
+Copyright (c) Edgeless Systems GmbH
+
+SPDX-License-Identifier: AGPL-3.0-only
+*/
+
+package etcdio
+
+import (
+	"syscall"
+
+	"golang.org/x/sys/unix"
+)
+
+func setioprio(ioPrioWhoProcess, pid, prioVal uintptr) (uintptr, uintptr, syscall.Errno) {
+	return unix.Syscall(unix.SYS_IOPRIO_SET, ioPrioWhoProcess, pid, prioVal)
+}