| #!/usr/bin/python |
| # -*- python -*- |
| # |
| # Copyright (C) 2019 Red Hat, Inc |
| # |
| # QEMU SystemTap Trace Tool |
| # |
| # This program is free software; you can redistribute it and/or modify |
| # it under the terms of the GNU General Public License as published by |
| # the Free Software Foundation; either version 2 of the License, or |
| # (at your option) any later version. |
| # |
| # This program is distributed in the hope that it will be useful, |
| # but WITHOUT ANY WARRANTY; without even the implied warranty of |
| # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| # GNU General Public License for more details. |
| # |
| # You should have received a copy of the GNU General Public License |
| # along with this program; if not, see <http://www.gnu.org/licenses/>. |
| |
| from __future__ import print_function |
| |
| import argparse |
| import copy |
| import os.path |
| import re |
| import subprocess |
| import sys |
| |
| |
| def probe_prefix(binary): |
| dirname, filename = os.path.split(binary) |
| return re.sub("-", ".", filename) + ".log" |
| |
| |
| def which(binary): |
| for path in os.environ["PATH"].split(os.pathsep): |
| if os.path.exists(os.path.join(path, binary)): |
| return os.path.join(path, binary) |
| |
| print("Unable to find '%s' in $PATH" % binary) |
| sys.exit(1) |
| |
| |
| def tapset_dir(binary): |
| dirname, filename = os.path.split(binary) |
| if dirname == '': |
| thisfile = which(binary) |
| else: |
| thisfile = os.path.realpath(binary) |
| if not os.path.exists(thisfile): |
| print("Unable to find '%s'" % thisfile) |
| sys.exit(1) |
| |
| basedir = os.path.split(thisfile)[0] |
| tapset = os.path.join(basedir, "..", "share", "systemtap", "tapset") |
| return os.path.realpath(tapset) |
| |
| |
| def tapset_env(tapset_dir): |
| tenv = copy.copy(os.environ) |
| tenv["SYSTEMTAP_TAPSET"] = tapset_dir |
| return tenv |
| |
| def cmd_run(args): |
| prefix = probe_prefix(args.binary) |
| tapsets = tapset_dir(args.binary) |
| |
| if args.verbose: |
| print("Using tapset dir '%s' for binary '%s'" % (tapsets, args.binary)) |
| |
| probes = [] |
| for probe in args.probes: |
| probes.append("probe %s.%s {}" % (prefix, probe)) |
| if len(probes) == 0: |
| print("At least one probe pattern must be specified") |
| sys.exit(1) |
| |
| script = " ".join(probes) |
| if args.verbose: |
| print("Compiling script '%s'" % script) |
| script = """probe begin { print("Running script, <Ctrl>-c to quit\\n") } """ + script |
| |
| # We request an 8MB buffer, since the stap default 1MB buffer |
| # can be easily overflowed by frequently firing QEMU traces |
| stapargs = ["stap", "-s", "8"] |
| if args.pid is not None: |
| stapargs.extend(["-x", args.pid]) |
| stapargs.extend(["-e", script]) |
| subprocess.call(stapargs, env=tapset_env(tapsets)) |
| |
| |
| def cmd_list(args): |
| tapsets = tapset_dir(args.binary) |
| |
| if args.verbose: |
| print("Using tapset dir '%s' for binary '%s'" % (tapsets, args.binary)) |
| |
| def print_probes(verbose, name): |
| prefix = probe_prefix(args.binary) |
| offset = len(prefix) + 1 |
| script = prefix + "." + name |
| |
| if verbose: |
| print("Listing probes with name '%s'" % script) |
| proc = subprocess.Popen(["stap", "-l", script], |
| stdout=subprocess.PIPE, env=tapset_env(tapsets)) |
| out, err = proc.communicate() |
| if proc.returncode != 0: |
| print("No probes found, are the tapsets installed in %s" % tapset_dir(args.binary)) |
| sys.exit(1) |
| |
| for line in out.splitlines(): |
| if line.startswith(prefix): |
| print("%s" % line[offset:]) |
| |
| if len(args.probes) == 0: |
| print_probes(args.verbose, "*") |
| else: |
| for probe in args.probes: |
| print_probes(args.verbose, probe) |
| |
| |
| def main(): |
| parser = argparse.ArgumentParser(description="QEMU SystemTap trace tool") |
| parser.add_argument("-v", "--verbose", help="Print verbose progress info", |
| action='store_true') |
| |
| subparser = parser.add_subparsers(help="commands") |
| subparser.required = True |
| subparser.dest = "command" |
| |
| runparser = subparser.add_parser("run", help="Run a trace session", |
| formatter_class=argparse.RawDescriptionHelpFormatter, |
| epilog=""" |
| |
| To watch all trace points on the qemu-system-x86_64 binary: |
| |
| %(argv0)s run qemu-system-x86_64 |
| |
| To only watch the trace points matching the qio* and qcrypto* patterns |
| |
| %(argv0)s run qemu-system-x86_64 'qio*' 'qcrypto*' |
| """ % {"argv0": sys.argv[0]}) |
| runparser.set_defaults(func=cmd_run) |
| runparser.add_argument("--pid", "-p", dest="pid", |
| help="Restrict tracing to a specific process ID") |
| runparser.add_argument("binary", help="QEMU system or user emulator binary") |
| runparser.add_argument("probes", help="Probe names or wildcards", |
| nargs=argparse.REMAINDER) |
| |
| listparser = subparser.add_parser("list", help="List probe points", |
| formatter_class=argparse.RawDescriptionHelpFormatter, |
| epilog=""" |
| |
| To list all trace points on the qemu-system-x86_64 binary: |
| |
| %(argv0)s list qemu-system-x86_64 |
| |
| To only list the trace points matching the qio* and qcrypto* patterns |
| |
| %(argv0)s list qemu-system-x86_64 'qio*' 'qcrypto*' |
| """ % {"argv0": sys.argv[0]}) |
| listparser.set_defaults(func=cmd_list) |
| listparser.add_argument("binary", help="QEMU system or user emulator binary") |
| listparser.add_argument("probes", help="Probe names or wildcards", |
| nargs=argparse.REMAINDER) |
| |
| args = parser.parse_args() |
| |
| args.func(args) |
| sys.exit(0) |
| |
| if __name__ == '__main__': |
| main() |