#! /usr/bin/env stap
# traceio.stp
# Copyright (C) 2007 Red Hat, Inc., Eugene Teo <eteo@redhat.com>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 2 as
# published by the Free Software Foundation.
#

global reads, writes, total_io

probe kernel.function("vfs_read").return {
	reads[execname()] += $return
}

probe kernel.function("vfs_write").return {
	writes[execname()] += $return
}

probe timer.s(1) {
	foreach (p in reads)
		total_io[p] += reads[p]
	foreach (p in writes)
		total_io[p] += writes[p]
	foreach(p in total_io- limit 10)
		printf("%15s r: %8d KiB w: %8d KiB\n",
			p, reads[p]/1024,
			writes[p]/1024)
		printf("\n")
	# Note we don't zero out reads, writes and total_io,
	# so the values are cumulative since the script started.
}