metrics: fix compilation for GOOS=js (#23449)

metrics/cputime_unix.go

@@ -0,0 +1,35 @@
+// Copyright 2018 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+// +build !windows,!js
+
+package metrics
+
+import (
+	syscall "golang.org/x/sys/unix"
+
+	"github.com/ethereum/go-ethereum/log"
+)
+
+// getProcessCPUTime retrieves the process' CPU time since program startup.
+func getProcessCPUTime() int64 {
+	var usage syscall.Rusage
+	if err := syscall.Getrusage(syscall.RUSAGE_SELF, &usage); err != nil {
+		log.Warn("Failed to retrieve CPU time", "err", err)
+		return 0
+	}
+	return int64(usage.Utime.Sec+usage.Stime.Sec)*100 + int64(usage.Utime.Usec+usage.Stime.Usec)/10000 //nolint:unconvert
+}