summaryrefslogtreecommitdiffstats
path: root/scripts/crosstap
blob: 40856bc208d5e38ab639a5dc6e1742f7033aff3a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
#!/usr/bin/env python3
#
# Build a systemtap script for a given image, kernel
#
# Effectively script extracts needed information from set of
# 'bitbake -e' commands and contructs proper invocation of stap on
# host to build systemtap script for a given target.
#
# By default script will compile scriptname.ko that could be copied
# to taget and activated with 'staprun scriptname.ko' command. Or if
# --remote user@hostname option is specified script will build, load
# execute script on target.
#
# This script is very similar and inspired by crosstap shell script.
# The major difference that this script supports user-land related
# systemtap script, whereas crosstap could deal only with scripts
# related to kernel.
#
# Copyright (c) 2018, Cisco Systems.
#
# SPDX-License-Identifier: GPL-2.0-only
#

import sys
import re
import subprocess
import os
import optparse

class Stap(object):
    def __init__(self, script, module, remote):
        self.script = script
        self.module = module
        self.remote = remote
        self.stap = None
        self.sysroot = None
        self.runtime = None
        self.tapset = None
        self.arch = None
        self.cross_compile = None
        self.kernel_release = None
        self.target_path = None
        self.target_ld_library_path = None

        if not self.remote:
            if not self.module:
                # derive module name from script
                self.module = os.path.basename(self.script)
                if self.module[-4:] == ".stp":
                    self.module = self.module[:-4]
                    # replace - if any with _
                    self.module = self.module.replace("-", "_")

    def command(self, args):
        ret = []
        ret.append(self.stap)

        if self.remote:
            ret.append("--remote")
            ret.append(self.remote)
        else:
            ret.append("-p4")
            ret.append("-m")
            ret.append(self.module)

        ret.append("-a")
        ret.append(self.arch)

        ret.append("-B")
        ret.append("CROSS_COMPILE=" + self.cross_compile)

        ret.append("-r")
        ret.append(self.kernel_release)

        ret.append("-I")
        ret.append(self.tapset)

        ret.append("-R")
        ret.append(self.runtime)

        if self.sysroot:
            ret.append("--sysroot")
            ret.append(self.sysroot)

            ret.append("--sysenv=PATH=" + self.target_path)
            ret.append("--sysenv=LD_LIBRARY_PATH=" + self.target_ld_library_path)

        ret = ret + args

        ret.append(self.script)
        return ret

    def additional_environment(self):
        ret = {}
        ret["SYSTEMTAP_DEBUGINFO_PATH"] = "+:.debug:build"
        return ret

    def environment(self):
        ret = os.environ.copy()
        additional = self.additional_environment()
        for e in additional:
            ret[e] = additional[e]
        return ret

    def display_command(self, args):
        additional_env = self.additional_environment()
        command = self.command(args)

        print("#!/bin/sh")
        for e in additional_env:
            print("export %s=\"%s\"" % (e, additional_env[e]))
        print(" ".join(command))

class BitbakeEnvInvocationException(Exception):
    def __init__(self, message):
        self.message = message

class BitbakeEnv(object):
    BITBAKE="bitbake"

    def __init__(self, package):
        self.package = package
        self.cmd = BitbakeEnv.BITBAKE + " -e " + self.package
        self.popen = subprocess.Popen(self.cmd, shell=True,
                                      stdout=subprocess.PIPE,
                                      stderr=subprocess.STDOUT)
        self.__lines = self.popen.stdout.readlines()
        self.popen.wait()

        self.lines = []
        for line in self.__lines:
                self.lines.append(line.decode('utf-8'))

    def get_vars(self, vars):
        if self.popen.returncode:
            raise BitbakeEnvInvocationException(
                "\nFailed to execute '" + self.cmd +
                "' with the following message:\n" +
                ''.join(self.lines))

        search_patterns = []
        retdict = {}
        for var in vars:
            # regular not exported variable
            rexpr = "^" + var + "=\"(.*)\""
            re_compiled = re.compile(rexpr)
            search_patterns.append((var, re_compiled))

            # exported variable
            rexpr = "^export " + var + "=\"(.*)\""
            re_compiled = re.compile(rexpr)
            search_patterns.append((var, re_compiled))

            for line in self.lines:
                for var, rexpr in search_patterns:
                    m = rexpr.match(line)
                    if m:
                        value = m.group(1)
                        retdict[var] = value

        # fill variables values in order how they were requested
        ret = []
        for var in vars:
            ret.append(retdict.get(var))

        # if it is single value list return it as scalar, not the list
        if len(ret) == 1:
            ret = ret[0]

        return ret

class ParamDiscovery(object):
    SYMBOLS_CHECK_MESSAGE = """
WARNING: image '%s' does not have dbg-pkgs IMAGE_FEATURES enabled and no
"image-combined-dbg" in inherited classes is specified. As result the image
does not have symbols for user-land processes DWARF based probes. Consider
adding 'dbg-pkgs' to EXTRA_IMAGE_FEATURES or adding "image-combined-dbg" to
USER_CLASSES. I.e add this line 'USER_CLASSES += "image-combined-dbg"' to
local.conf file.

Or you may use IMAGE_GEN_DEBUGFS="1" option, and then after build you need
recombine/unpack image and image-dbg tarballs and pass resulting dir location
with --sysroot option.
"""

    def __init__(self, image):
        self.image = image

        self.image_rootfs = None
        self.image_features = None
        self.image_gen_debugfs = None
        self.inherit = None
        self.base_bindir = None
        self.base_sbindir = None
        self.base_libdir = None
        self.bindir = None
        self.sbindir = None
        self.libdir = None

        self.staging_bindir_toolchain = None
        self.target_prefix = None
        self.target_arch = None
        self.target_kernel_builddir = None

        self.staging_dir_native = None

        self.image_combined_dbg = False

    def discover(self):
        if self.image:
            benv_image = BitbakeEnv(self.image)
            (self.image_rootfs,
             self.image_features,
             self.image_gen_debugfs,
             self.inherit,
             self.base_bindir,
             self.base_sbindir,
             self.base_libdir,
             self.bindir,
             self.sbindir,
             self.libdir
            ) = benv_image.get_vars(
                 ("IMAGE_ROOTFS",
                  "IMAGE_FEATURES",
                  "IMAGE_GEN_DEBUGFS",
                  "INHERIT",
                  "base_bindir",
                  "base_sbindir",
                  "base_libdir",
                  "bindir",
                  "sbindir",
                  "libdir"
                  ))

        benv_kernel = BitbakeEnv("virtual/kernel")
        (self.staging_bindir_toolchain,
         self.target_prefix,
         self.target_arch,
         self.target_kernel_builddir
        ) = benv_kernel.get_vars(
             ("STAGING_BINDIR_TOOLCHAIN",
              "TARGET_PREFIX",
              "TRANSLATED_TARGET_ARCH",
              "B"
            ))

        benv_systemtap = BitbakeEnv("systemtap-native")
        (self.staging_dir_native
        ) = benv_systemtap.get_vars(["STAGING_DIR_NATIVE"])

        if self.inherit:
            if "image-combined-dbg" in self.inherit.split():
                self.image_combined_dbg = True

    def check(self, sysroot_option):
        ret = True
        if self.image_rootfs:
            sysroot = self.image_rootfs
            if not os.path.isdir(self.image_rootfs):
                print("ERROR: Cannot find '" + sysroot +
                      "' directory. Was '" + self.image + "' image built?")
                ret = False

        stap = self.staging_dir_native + "/usr/bin/stap"
        if not os.path.isfile(stap):
            print("ERROR: Cannot find '" + stap +
                  "'. Was 'systemtap-native' built?")
            ret = False

        if not os.path.isdir(self.target_kernel_builddir):
            print("ERROR: Cannot find '" + self.target_kernel_builddir +
                  "' directory. Was 'kernel/virtual' built?")
            ret = False

        if not sysroot_option and self.image_rootfs:
            dbg_pkgs_found = False

            if self.image_features:
                image_features = self.image_features.split()
                if "dbg-pkgs" in image_features:
                    dbg_pkgs_found = True

            if not dbg_pkgs_found \
               and not self.image_combined_dbg:
                print(ParamDiscovery.SYMBOLS_CHECK_MESSAGE % (self.image))

        if not ret:
            print("")

        return ret

    def __map_systemtap_arch(self):
        a = self.target_arch
        ret = a
        if   re.match('(athlon|x86.64)$', a):
            ret = 'x86_64'
        elif re.match('i.86$', a):
            ret = 'i386'
        elif re.match('arm$', a):
            ret = 'arm'
        elif re.match('aarch64$', a):
            ret = 'arm64'
        elif re.match('mips(isa|)(32|64|)(r6|)(el|)$', a):
            ret = 'mips'
        elif re.match('p(pc|owerpc)(|64)', a):
            ret = 'powerpc'
        return ret

    def fill_stap(self, stap):
        stap.stap = self.staging_dir_native + "/usr/bin/stap"
        if not stap.sysroot:
            if self.image_rootfs:
                if self.image_combined_dbg:
                    stap.sysroot = self.image_rootfs + "-dbg"
                else:
                    stap.sysroot = self.image_rootfs
        stap.runtime = self.staging_dir_native + "/usr/share/systemtap/runtime"
        stap.tapset = self.staging_dir_native + "/usr/share/systemtap/tapset"
        stap.arch = self.__map_systemtap_arch()
        stap.cross_compile = self.staging_bindir_toolchain + "/" + \
                             self.target_prefix
        stap.kernel_release = self.target_kernel_builddir

        # do we have standard that tells in which order these need to appear
        target_path = []
        if self.sbindir:
            target_path.append(self.sbindir)
        if self.bindir:
            target_path.append(self.bindir)
        if self.base_sbindir:
            target_path.append(self.base_sbindir)
        if self.base_bindir:
            target_path.append(self.base_bindir)
        stap.target_path = ":".join(target_path)

        target_ld_library_path = []
        if self.libdir:
            target_ld_library_path.append(self.libdir)
        if self.base_libdir:
            target_ld_library_path.append(self.base_libdir)
        stap.target_ld_library_path = ":".join(target_ld_library_path)


def main():
    usage = """usage: %prog -s <systemtap-script> [options] [-- [systemtap options]]

%prog cross compile given SystemTap script against given image, kernel

It needs to run in environtment set for bitbake - it uses bitbake -e
invocations to retrieve information to construct proper stap cross build
invocation arguments. It assumes that systemtap-native is built in given
bitbake workspace.

Anything after -- option is passed directly to stap.

Legacy script invocation style supported but depreciated:
  %prog <user@hostname> <sytemtap-script> [systemtap options]

To enable most out of systemtap the following site.conf or local.conf
configuration is recommended:

# enables symbol + target binaries rootfs-dbg in workspace
IMAGE_GEN_DEBUGFS = "1"
IMAGE_FSTYPES_DEBUGFS = "tar.bz2"
USER_CLASSES += "image-combined-dbg"

# enables kernel debug symbols
KERNEL_EXTRA_FEATURES_append = " features/debug/debug-kernel.scc"

# minimal, just run-time systemtap configuration in target image
PACKAGECONFIG_pn-systemtap = "monitor"

# add systemtap run-time into target image if it is not there yet
IMAGE_INSTALL_append = " systemtap"
"""
    option_parser = optparse.OptionParser(usage=usage)

    option_parser.add_option("-s", "--script", dest="script",
                             help="specify input script FILE name",
                             metavar="FILE")

    option_parser.add_option("-i", "--image", dest="image",
                             help="specify image name for which script should be compiled")

    option_parser.add_option("-r", "--remote", dest="remote",
                             help="specify username@hostname of remote target to run script "
                             "optional, it assumes that remote target can be accessed through ssh")

    option_parser.add_option("-m", "--module", dest="module",
                             help="specify module name, optional, has effect only if --remote is not used, "
                             "if not specified module name will be derived from passed script name")

    option_parser.add_option("-y", "--sysroot", dest="sysroot",
                             help="explicitely specify image sysroot location. May need to use it in case "
                             "when IMAGE_GEN_DEBUGFS=\"1\" option is used and recombined with symbols "
                             "in different location",
                             metavar="DIR")

    option_parser.add_option("-o", "--out", dest="out",
                             action="store_true",
                             help="output shell script that equvivalent invocation of this script with "
                             "given set of arguments, in given bitbake environment. It could be stored in "
                             "separate shell script and could be repeated without incuring bitbake -e "
                             "invocation overhead",
                             default=False)

    option_parser.add_option("-d", "--debug", dest="debug",
                             action="store_true",
                             help="enable debug output. Use this option to see resulting stap invocation",
                             default=False)

    # is invocation follow syntax from orignal crosstap shell script
    legacy_args = False

    # check if we called the legacy way
    if len(sys.argv) >= 3:
        if sys.argv[1].find("@") != -1 and os.path.exists(sys.argv[2]):
            legacy_args = True

            # fill options values for legacy invocation case
            options = optparse.Values
            options.script = sys.argv[2]
            options.remote = sys.argv[1]
            options.image = None
            options.module = None
            options.sysroot = None
            options.out = None
            options.debug = None
            remaining_args = sys.argv[3:]

    if not legacy_args:
        (options, remaining_args) = option_parser.parse_args()

    if not options.script or not os.path.exists(options.script):
        print("'-s FILE' option is missing\n")
        option_parser.print_help()
    else:
        stap = Stap(options.script, options.module, options.remote)
        discovery = ParamDiscovery(options.image)
        discovery.discover()
        if not discovery.check(options.sysroot):
            option_parser.print_help()
        else:
            stap.sysroot = options.sysroot
            discovery.fill_stap(stap)

            if options.out:
                stap.display_command(remaining_args)
            else:
                cmd = stap.command(remaining_args)
                env = stap.environment()

                if options.debug:
                    print(" ".join(cmd))

                os.execve(cmd[0], cmd, env)

main()