feat: Detect clock source (#923)

src/proc.sh

@@ -9,6 +9,23 @@ set -Eeuo pipefail
 : "${CPU_MODEL:=""}"
 : "${DEF_MODEL:="qemu64"}"
 
+CLOCKSOURCE="tsc"
+[[ "${ARCH,,}" == "arm64" ]] && CLOCKSOURCE="arch_sys_counter"
+CLOCK="/sys/devices/system/clocksource/clocksource0/current_clocksource"
+
+if [ ! -f "$CLOCK" ]; then
+  warn "file \"$CLOCK\" cannot not found?"
+else
+  result=$(<"$CLOCK")
+  case "${result,,}" in
+    "${CLOCKSOURCE,,}" ) ;;
+    "kvm-clock" ) info "Nested KVM virtualization detected.." ;;
+    "hyperv_clocksource_tsc_page" ) info "Nested Hyper-V virtualization detected.." ;;
+    "hpet" ) warn "unsupported clock source detected: '$result'. Please set host clock source to '$CLOCKSOURCE'" ;;
+    *) warn "unexpected clock source detected: '$result'. Please set host clock source to '$CLOCKSOURCE'" ;;
+  esac
+fi
+
 if [[ "${ARCH,,}" != "amd64" ]]; then
   KVM="N"
   warn "your CPU architecture is ${ARCH^^} and cannot provide KVM acceleration for x64 instructions, this will cause a major loss of performance."
@@ -47,7 +64,6 @@ fi
 if [[ "$KVM" != [Nn]* ]]; then
 
   CPU_FEATURES="kvm=on,l3-cache=on,+hypervisor"
-  CLOCK="/sys/devices/system/clocksource/clocksource0/current_clocksource"
   KVM_OPTS=",accel=kvm -enable-kvm -global kvm-pit.lost_tick_policy=discard"
 
   if ! grep -qw "sse4_2" <<< "$flags"; then
@@ -61,15 +77,6 @@ if [[ "$KVM" != [Nn]* ]]; then
     CPU_FEATURES+=",migratable=no"
   fi
 
-  if [ -f "$CLOCK" ]; then
-    CLOCK=$(<"$CLOCK")
-    if [[ "${CLOCK,,}" != "tsc" ]]; then
-      warn "unexpected clocksource: $CLOCK"
-    fi
-  else
-    warn "file \"$CLOCK\" cannot not found?"
-  fi
-
   if grep -qw "svm" <<< "$flags"; then
 
     # AMD processor
@@ -127,7 +134,7 @@ else
 fi
 
 if [ -z "$HOST_CPU" ]; then
-  HOST_CPU=$(lscpu | grep -m 1 'Model name' | cut -f 2 -d ":" | awk '{$1=$1}1' | sed 's# @.*##g' | sed s/"(R)"//g | sed 's/[^[:alnum:] ]\+/ /g' | sed 's/  */ /g')
+  [[ "${CPU,,}" != "unknown" ]] && HOST_CPU="$CPU"
 fi
 
 if [ -n "$HOST_CPU" ]; then