Stefan Hajnoczi | 3f00971 | 2020-01-07 11:24:38 +0000 | [diff] [blame] | 1 | #!/usr/bin/env python3 |
Daniel P. Berrangé | 62dd104 | 2019-01-23 12:00:16 +0000 | [diff] [blame] | 2 | # -*- python -*- |
| 3 | # |
| 4 | # Copyright (C) 2019 Red Hat, Inc |
| 5 | # |
| 6 | # QEMU SystemTap Trace Tool |
| 7 | # |
| 8 | # This program is free software; you can redistribute it and/or modify |
| 9 | # it under the terms of the GNU General Public License as published by |
| 10 | # the Free Software Foundation; either version 2 of the License, or |
| 11 | # (at your option) any later version. |
| 12 | # |
| 13 | # This program is distributed in the hope that it will be useful, |
| 14 | # but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 16 | # GNU General Public License for more details. |
| 17 | # |
| 18 | # You should have received a copy of the GNU General Public License |
| 19 | # along with this program; if not, see <http://www.gnu.org/licenses/>. |
| 20 | |
Daniel P. Berrangé | 62dd104 | 2019-01-23 12:00:16 +0000 | [diff] [blame] | 21 | import argparse |
| 22 | import copy |
| 23 | import os.path |
| 24 | import re |
| 25 | import subprocess |
| 26 | import sys |
| 27 | |
| 28 | |
| 29 | def probe_prefix(binary): |
| 30 | dirname, filename = os.path.split(binary) |
| 31 | return re.sub("-", ".", filename) + ".log" |
| 32 | |
| 33 | |
| 34 | def which(binary): |
| 35 | for path in os.environ["PATH"].split(os.pathsep): |
| 36 | if os.path.exists(os.path.join(path, binary)): |
| 37 | return os.path.join(path, binary) |
| 38 | |
| 39 | print("Unable to find '%s' in $PATH" % binary) |
| 40 | sys.exit(1) |
| 41 | |
| 42 | |
| 43 | def tapset_dir(binary): |
| 44 | dirname, filename = os.path.split(binary) |
| 45 | if dirname == '': |
| 46 | thisfile = which(binary) |
| 47 | else: |
| 48 | thisfile = os.path.realpath(binary) |
| 49 | if not os.path.exists(thisfile): |
| 50 | print("Unable to find '%s'" % thisfile) |
| 51 | sys.exit(1) |
| 52 | |
| 53 | basedir = os.path.split(thisfile)[0] |
| 54 | tapset = os.path.join(basedir, "..", "share", "systemtap", "tapset") |
| 55 | return os.path.realpath(tapset) |
| 56 | |
| 57 | |
| 58 | def tapset_env(tapset_dir): |
| 59 | tenv = copy.copy(os.environ) |
| 60 | tenv["SYSTEMTAP_TAPSET"] = tapset_dir |
| 61 | return tenv |
| 62 | |
| 63 | def cmd_run(args): |
| 64 | prefix = probe_prefix(args.binary) |
| 65 | tapsets = tapset_dir(args.binary) |
| 66 | |
| 67 | if args.verbose: |
| 68 | print("Using tapset dir '%s' for binary '%s'" % (tapsets, args.binary)) |
| 69 | |
| 70 | probes = [] |
| 71 | for probe in args.probes: |
| 72 | probes.append("probe %s.%s {}" % (prefix, probe)) |
| 73 | if len(probes) == 0: |
| 74 | print("At least one probe pattern must be specified") |
| 75 | sys.exit(1) |
| 76 | |
| 77 | script = " ".join(probes) |
| 78 | if args.verbose: |
| 79 | print("Compiling script '%s'" % script) |
| 80 | script = """probe begin { print("Running script, <Ctrl>-c to quit\\n") } """ + script |
| 81 | |
| 82 | # We request an 8MB buffer, since the stap default 1MB buffer |
| 83 | # can be easily overflowed by frequently firing QEMU traces |
| 84 | stapargs = ["stap", "-s", "8"] |
| 85 | if args.pid is not None: |
| 86 | stapargs.extend(["-x", args.pid]) |
| 87 | stapargs.extend(["-e", script]) |
| 88 | subprocess.call(stapargs, env=tapset_env(tapsets)) |
| 89 | |
| 90 | |
| 91 | def cmd_list(args): |
| 92 | tapsets = tapset_dir(args.binary) |
| 93 | |
| 94 | if args.verbose: |
| 95 | print("Using tapset dir '%s' for binary '%s'" % (tapsets, args.binary)) |
| 96 | |
| 97 | def print_probes(verbose, name): |
| 98 | prefix = probe_prefix(args.binary) |
| 99 | offset = len(prefix) + 1 |
| 100 | script = prefix + "." + name |
| 101 | |
| 102 | if verbose: |
| 103 | print("Listing probes with name '%s'" % script) |
| 104 | proc = subprocess.Popen(["stap", "-l", script], |
Stefan Hajnoczi | 3f00971 | 2020-01-07 11:24:38 +0000 | [diff] [blame] | 105 | stdout=subprocess.PIPE, |
| 106 | universal_newlines=True, |
| 107 | env=tapset_env(tapsets)) |
Daniel P. Berrangé | 62dd104 | 2019-01-23 12:00:16 +0000 | [diff] [blame] | 108 | out, err = proc.communicate() |
| 109 | if proc.returncode != 0: |
| 110 | print("No probes found, are the tapsets installed in %s" % tapset_dir(args.binary)) |
| 111 | sys.exit(1) |
| 112 | |
| 113 | for line in out.splitlines(): |
| 114 | if line.startswith(prefix): |
| 115 | print("%s" % line[offset:]) |
| 116 | |
| 117 | if len(args.probes) == 0: |
| 118 | print_probes(args.verbose, "*") |
| 119 | else: |
| 120 | for probe in args.probes: |
| 121 | print_probes(args.verbose, probe) |
| 122 | |
| 123 | |
| 124 | def main(): |
| 125 | parser = argparse.ArgumentParser(description="QEMU SystemTap trace tool") |
| 126 | parser.add_argument("-v", "--verbose", help="Print verbose progress info", |
| 127 | action='store_true') |
| 128 | |
| 129 | subparser = parser.add_subparsers(help="commands") |
| 130 | subparser.required = True |
| 131 | subparser.dest = "command" |
| 132 | |
| 133 | runparser = subparser.add_parser("run", help="Run a trace session", |
| 134 | formatter_class=argparse.RawDescriptionHelpFormatter, |
| 135 | epilog=""" |
| 136 | |
| 137 | To watch all trace points on the qemu-system-x86_64 binary: |
| 138 | |
| 139 | %(argv0)s run qemu-system-x86_64 |
| 140 | |
| 141 | To only watch the trace points matching the qio* and qcrypto* patterns |
| 142 | |
| 143 | %(argv0)s run qemu-system-x86_64 'qio*' 'qcrypto*' |
| 144 | """ % {"argv0": sys.argv[0]}) |
| 145 | runparser.set_defaults(func=cmd_run) |
| 146 | runparser.add_argument("--pid", "-p", dest="pid", |
| 147 | help="Restrict tracing to a specific process ID") |
| 148 | runparser.add_argument("binary", help="QEMU system or user emulator binary") |
| 149 | runparser.add_argument("probes", help="Probe names or wildcards", |
| 150 | nargs=argparse.REMAINDER) |
| 151 | |
| 152 | listparser = subparser.add_parser("list", help="List probe points", |
| 153 | formatter_class=argparse.RawDescriptionHelpFormatter, |
| 154 | epilog=""" |
| 155 | |
| 156 | To list all trace points on the qemu-system-x86_64 binary: |
| 157 | |
| 158 | %(argv0)s list qemu-system-x86_64 |
| 159 | |
| 160 | To only list the trace points matching the qio* and qcrypto* patterns |
| 161 | |
| 162 | %(argv0)s list qemu-system-x86_64 'qio*' 'qcrypto*' |
| 163 | """ % {"argv0": sys.argv[0]}) |
| 164 | listparser.set_defaults(func=cmd_list) |
| 165 | listparser.add_argument("binary", help="QEMU system or user emulator binary") |
| 166 | listparser.add_argument("probes", help="Probe names or wildcards", |
| 167 | nargs=argparse.REMAINDER) |
| 168 | |
| 169 | args = parser.parse_args() |
| 170 | |
| 171 | args.func(args) |
| 172 | sys.exit(0) |
| 173 | |
| 174 | if __name__ == '__main__': |
| 175 | main() |