msrcount.bt

#!/usr/bin/env bpftrace
#
# This tool shows MSR writes/reads count by MSR address
#
# This can help in diagnose when see a lot of MSR reads/writes
# during profiling.
#
# Copyright 2020 Aleksei Zakharov
# Licensed under the Apache License, Version 2.0 (the "License")

BEGIN
{
	printf("Tracing write/read msr...\n");
}

tracepoint:msr:write_msr
{
	@w[args->msr]=count();
}

tracepoint:msr:read_msr
{
	@r[args->msr]=count();
}

i:s:1
{
	printf("MSR_WRITE:\n");
	print(@w);
	clear(@w);
	printf("MSR_READ:\n");
	print(@r);
	clear(@r);
}

END
{
	clear(@w);
	clear(@r);
}