#!/bin/sh # # $NetBSD: smtoff,v 1.4.2.2 2019/05/14 11:33:42 martin Exp $ # # Public Domain. # # PROVIDE: smtoff # REQUIRE: root bootconf mountcritlocal tty $_rc_subr_loaded . /etc/rc.subr name="smtoff" rcvar=$name start_cmd="smtoff_start" stop_cmd="smtoff_stop" # ------------------------------------------------------------------------------ # # The format of the output is: # # ... # cpu0: SMT ID 1 # ... # # Return the value. # GetSmtId() { cpuctl identify "$1" | while read cpuN smt id N junk do test -n "$junk" && continue case "${smt} ${id}" in 'SMT ID') case "$N" in [0-9]|[1-9][0-9]|[1-9][0-9]*[0-9]) printf %s "$N" return ;; esac ;; esac done } CountCPUs() { sysctl -n hw.ncpu } # ------------------------------------------------------------------------------ # # Disable SMT. We skip cpu0. # smtoff_start() { ncpus=$(CountCPUs) i=1 while [ "$i" -lt "$ncpus" ] do smtid=$(GetSmtId "$i" 2>/dev/null) case "$smtid" in '') # Didn't get the ID? Then maybe no SMT. ;; 0) # The first thread is never disabled. ;; *) cpuctl offline "$i" ;; esac i=$(($i+1)) done } # # Enable SMT. We basically turn on each CPU. # smtoff_stop() { ncpus=$(CountCPUs) i=1 while [ "$i" -lt "$ncpus" ] do cpuctl online "$i" i=$(($i+1)) done } load_rc_config $name run_rc_command "$1"