1 // Copyright 2013 The Go Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style 3 // license that can be found in the LICENSE file. 4 5 package runtime 6 7 func checkgoarm() { 8 // TODO(minux): FP checks like in os_linux_arm.go. 9 10 // osinit not called yet, so ncpu not set: must use getncpu directly. 11 if getncpu() > 1 && goarm < 7 { 12 print("runtime: this system has multiple CPUs and must use\n") 13 print("atomic synchronization instructions. Recompile using GOARM=7.\n") 14 exit(1) 15 } 16 } 17 18 //go:nosplit 19 func cputicks() int64 { 20 // Currently cputicks() is used in blocking profiler and to seed runtime·fastrand(). 21 // runtime·nanotime() is a poor approximation of CPU ticks that is enough for the profiler. 22 // TODO: need more entropy to better seed fastrand. 23 return nanotime() 24 } 25