name : kvm-get-cpus-script.sh #!/bin/sh # SPDX-License-Identifier: GPL-2.0+ # # Create an awk script that takes as input numbers of CPUs and outputs # lists of CPUs, one per line in both cases. # # Usage: kvm-get-cpus-script.sh /path/to/cpu/arrays /path/to/put/script [ /path/to/state ] # # The CPU arrays are output by kvm-assign-cpus.sh, and are valid awk # statements initializing the variables describing the system's topology. # # The optional state is input by this script (if the file exists and is # non-empty), and can also be output by this script. cpuarrays="${1-/sys/devices/system/node}" scriptfile="${2}" statefile="${3}" if ! test -f "$cpuarrays" then echo "File not found: $cpuarrays" 1>&2 exit 1 fi scriptdir="`dirname "$scriptfile"`" if ! test -d "$scriptdir" || ! test -x "$scriptdir" || ! test -w "$scriptdir" then echo "Directory not usable for script output: $scriptdir" exit 1 fi cat << '___EOF___' > "$scriptfile" BEGIN { ___EOF___ cat "$cpuarrays" >> "$scriptfile" if test -r "$statefile" then cat "$statefile" >> "$scriptfile" fi cat << '___EOF___' >> "$scriptfile" } # Do we have the system architecture to guide CPU affinity? function gotcpus() { return numnodes != ""; } # Return a comma-separated list of the next n CPUs. function nextcpus(n, i, s) { for (i = 0; i < n; i++) { if (nodecpus[curnode] == "") curnode = 0; if (cpu[curnode][curcpu[curnode]] == "") curcpu[curnode] = 0; if (s != "") s = s ","; s = s cpu[curnode][curcpu[curnode]]; curcpu[curnode]++; curnode++ } return s; } # Dump out the current node/CPU state so that a later invocation of this # script can continue where this one left off. Of course, this only works # when a state file was specified and where there was valid sysfs state. # Returns 1 if the state was dumped, 0 otherwise. # # Dumping the state for one system configuration and loading it into # another isn't likely to do what you want, whatever that might be. function dumpcpustate( i, fn) { ___EOF___ echo ' fn = "'"$statefile"'";' >> $scriptfile cat << '___EOF___' >> "$scriptfile" if (fn != "" && gotcpus()) { print "curnode = " curnode ";" > fn; for (i = 0; i < numnodes; i++) if (curcpu[i] != "") print "curcpu[" i "] = " curcpu[i] ";" >> fn; return 1; } if (fn != "") print "# No CPU state to dump." > fn; return 0; } ___EOF___