aboutsummaryrefslogtreecommitdiffstats
path: root/src/vpp-api/python/vpp_papi/vpp_stats.py
blob: b407b56a85f90ec27bb3aabfc5675b9b6d726238 (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
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
#!/usr/bin/env python3
#
# Copyright (c) 2021 Cisco and/or its affiliates.
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at:
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#

'''
This module implement Python access to the VPP statistics segment. It
accesses the data structures directly in shared memory.
VPP uses optimistic locking, so data structures may change underneath
us while we are reading. Data is copied out and it's important to
spend as little time as possible "holding the lock".

Counters are stored in VPP as a two dimensional array.
Index by thread and index (typically sw_if_index).
Simple counters count only packets, Combined counters count packets
and octets.

Counters can be accessed in either dimension.
stat['/if/rx'] - returns 2D lists
stat['/if/rx'][0] - returns counters for all interfaces for thread 0
stat['/if/rx'][0][1] - returns counter for interface 1 on thread 0
stat['/if/rx'][0][1]['packets'] - returns the packet counter
                                  for interface 1 on thread 0
stat['/if/rx'][:, 1] - returns the counters for interface 1 on all threads
stat['/if/rx'][:, 1].packets() - returns the packet counters for
                                 interface 1 on all threads
stat['/if/rx'][:, 1].sum_packets() - returns the sum of packet counters for
                                     interface 1 on all threads
stat['/if/rx-miss'][:, 1].sum() - returns the sum of packet counters for
                                  interface 1 on all threads for simple counters
'''

import os
import socket
import array
import mmap
from struct import Struct
import time
import unittest
import re

def recv_fd(sock):
    '''Get file descriptor for memory map'''
    fds = array.array("i")   # Array of ints
    _, ancdata, _, _ = sock.recvmsg(0, socket.CMSG_LEN(4))
    for cmsg_level, cmsg_type, cmsg_data in ancdata:
        if cmsg_level == socket.SOL_SOCKET and cmsg_type == socket.SCM_RIGHTS:
            fds.frombytes(cmsg_data[:len(cmsg_data) - (len(cmsg_data) % fds.itemsize)])
    return list(fds)[0]

VEC_LEN_FMT = Struct('I')
def get_vec_len(stats, vector_offset):
    '''Equivalent to VPP vec_len()'''
    return VEC_LEN_FMT.unpack_from(stats.statseg, vector_offset - 8)[0]

def get_string(stats, ptr):
    '''Get a string from a VPP vector'''
    namevector = ptr - stats.base
    namevectorlen = get_vec_len(stats, namevector)
    if namevector + namevectorlen >= stats.size:
        raise IOError('String overruns stats segment')
    return stats.statseg[namevector:namevector+namevectorlen-1].decode('ascii')


class StatsVector:
    '''A class representing a VPP vector'''

    def __init__(self, stats, ptr, fmt):
        self.vec_start = ptr - stats.base
        self.vec_len = get_vec_len(stats, ptr - stats.base)
        self.struct = Struct(fmt)
        self.fmtlen = len(fmt)
        self.elementsize = self.struct.size
        self.statseg = stats.statseg
        self.stats = stats

        if self.vec_start + self.vec_len * self.elementsize >= stats.size:
            raise IOError('Vector overruns stats segment')

    def __iter__(self):
        with self.stats.lock:
            return self.struct.iter_unpack(self.statseg[self.vec_start:self.vec_start +
                                                        self.elementsize*self.vec_len])

    def __getitem__(self, index):
        if index > self.vec_len:
            raise IOError('Index beyond end of vector')
        with self.stats.lock:
            if self.fmtlen == 1:
                return self.struct.unpack_from(self.statseg, self.vec_start +
                                               (index * self.elementsize))[0]
            return self.struct.unpack_from(self.statseg, self.vec_start +
                                           (index * self.elementsize))

class VPPStats():
    '''Main class implementing Python access to the VPP statistics segment'''
    # pylint: disable=too-many-instance-attributes
    shared_headerfmt = Struct('QPQQPP')
    default_socketname = '/run/vpp/stats.sock'

    def __init__(self, socketname=default_socketname, timeout=10):
        self.socketname = socketname
        self.timeout = timeout
        self.directory = {}
        self.lock = StatsLock(self)
        self.connected = False
        self.size = 0
        self.last_epoch = 0
        self.error_vectors = 0
        self.statseg = 0

    def connect(self):
        '''Connect to stats segment'''
        if self.connected:
            return
        sock = socket.socket(socket.AF_UNIX, socket.SOCK_SEQPACKET)
        sock.connect(self.socketname)

        mfd = recv_fd(sock)
        sock.close()

        stat_result = os.fstat(mfd)
        self.statseg = mmap.mmap(mfd, stat_result.st_size, mmap.PROT_READ, mmap.MAP_SHARED)
        os.close(mfd)

        self.size = stat_result.st_size
        if self.version != 2:
            raise Exception('Incompatbile stat segment version {}'
                            .format(self.version))

        self.refresh()
        self.connected = True

    def disconnect(self):
        '''Disconnect from stats segment'''
        if self.connected:
            self.statseg.close()
            self.connected = False

    @property
    def version(self):
        '''Get version of stats segment'''
        return self.shared_headerfmt.unpack_from(self.statseg)[0]

    @property
    def base(self):
        '''Get base pointer of stats segment'''
        return self.shared_headerfmt.unpack_from(self.statseg)[1]

    @property
    def epoch(self):
        '''Get current epoch value from stats segment'''
        return self.shared_headerfmt.unpack_from(self.statseg)[2]

    @property
    def in_progress(self):
        '''Get value of in_progress from stats segment'''
        return self.shared_headerfmt.unpack_from(self.statseg)[3]

    @property
    def directory_vector(self):
        '''Get pointer of directory vector'''
        return self.shared_headerfmt.unpack_from(self.statseg)[4]

    @property
    def error_vector(self):
        '''Get pointer of error vector'''
        return self.shared_headerfmt.unpack_from(self.statseg)[5]

    elementfmt = 'IQ128s'

    def refresh(self, blocking=True):
        '''Refresh directory vector cache (epoch changed)'''
        directory = {}
        directory_by_idx = {}
        while True:
            try:
                with self.lock:
                    self.last_epoch = self.epoch
                    for i, direntry in enumerate(StatsVector(self, self.directory_vector, self.elementfmt)):
                        path_raw = direntry[2].find(b'\x00')
                        path = direntry[2][:path_raw].decode('ascii')
                        directory[path] = StatsEntry(direntry[0], direntry[1])
                        directory_by_idx[i] = path
                    self.directory = directory
                    self.directory_by_idx = directory_by_idx

                    # Cache the error index vectors
                    self.error_vectors = []
                    for threads in StatsVector(self, self.error_vector, 'P'):
                        self.error_vectors.append(StatsVector(self, threads[0], 'Q'))
                # Return statement must be outside the lock block to be sure
                # lock.release is executed
                return
            except IOError:
                if not blocking:
                    raise

    def __getitem__(self, item, blocking=True):
        if not self.connected:
            self.connect()
        while True:
            try:
                if self.last_epoch != self.epoch:
                    self.refresh(blocking)
                with self.lock:
                    result = self.directory[item].get_counter(self)
                # Return statement must be outside the lock block to be sure
                # lock.release is executed
                return result
            except IOError:
                if not blocking:
                    raise

    def __iter__(self):
        return iter(self.directory.items())

    def set_errors(self, blocking=True):
        '''Return dictionary of error counters > 0'''
        if not self.connected:
            self.connect()

        errors = {k:v for k, v in self.directory.items() if k.startswith("/err/")}
        result = {}
        while True:
            try:
                if self.last_epoch != self.epoch:
                    self.refresh(blocking)
                with self.lock:
                    for k, entry in errors.items():
                        total = 0
                        i = entry.value
                        for per_thread in self.error_vectors:
                            total += per_thread[i]
                        if total:
                            result[k] = total
                return result
            except IOError:
                if not blocking:
                    raise

    def set_errors_str(self, blocking=True):
        '''Return all errors counters > 0 pretty printed'''
        error_string = ['ERRORS:']
        error_counters = self.set_errors(blocking)
        for k in sorted(error_counters):
            error_string.append('{:<60}{:>10}'.format(k, error_counters[k]))
        return '%s\n' % '\n'.join(error_string)

    def get_counter(self, name, blocking=True):
        '''Alternative call to __getitem__'''
        return self.__getitem__(name, blocking)

    def get_err_counter(self, name, blocking=True):
        '''Return a single value (sum of all threads)'''
        if not self.connected:
            self.connect()
        if name.startswith("/err/"):
            while True:
                try:
                    if self.last_epoch != self.epoch:
                        self.refresh(blocking)
                    with self.lock:
                        result =  sum(self.directory[name].get_counter(self))
                    # Return statement must be outside the lock block to be sure
                    # lock.release is executed
                    return result
                except IOError:
                    if not blocking:
                        raise

    def ls(self, patterns):
        '''Returns list of counters matching pattern'''
        # pylint: disable=invalid-name
        if not self.connected:
            self.connect()
        if not isinstance(patterns, list):
            patterns = [patterns]
        regex = [re.compile(i) for i in patterns]
        return [k for k, v in self.directory.items()
                if any(re.match(pattern, k) for pattern in regex)]

    def dump(self, counters, blocking=True):
        '''Given a list of counters return a dictionary of results'''
        if not self.connected:
            self.connect()
        result = {}
        for cnt in counters:
            result[cnt] = self.__getitem__(cnt,blocking)
        return result

class StatsLock():
    '''Stat segment optimistic locking'''

    def __init__(self, stats):
        self.stats = stats
        self.epoch = 0

    def __enter__(self):
        acquired = self.acquire(blocking=True)
        assert acquired, "Lock wasn't acquired, but blocking=True"
        return self

    def __exit__(self, exc_type=None, exc_value=None, traceback=None):
        self.release()

    def acquire(self, blocking=True, timeout=-1):
        '''Acquire the lock. Await in progress to go false. Record epoch.'''
        self.epoch = self.stats.epoch
        if timeout > 0:
            start = time.monotonic()
        while self.stats.in_progress:
            if not blocking:
                time.sleep(0.01)
                if timeout > 0:
                    if start + time.monotonic() > timeout:
                        return False
        return True

    def release(self):
        '''Check if data read while locked is valid'''
        if self.stats.in_progress or self.stats.epoch != self.epoch:
            raise IOError('Optimistic lock failed, retry')

    def locked(self):
        '''Not used'''


class StatsCombinedList(list):
    '''Column slicing for Combined counters list'''

    def __getitem__(self, item):
        '''Supports partial numpy style 2d support. Slice by column [:,1]'''
        if isinstance(item, int):
            return list.__getitem__(self, item)
        return CombinedList([row[item[1]] for row in self])

class CombinedList(list):
    '''Combined Counters 2-dimensional by thread by index of packets/octets'''

    def packets(self):
        '''Return column (2nd dimension). Packets for all threads'''
        return [pair[0] for pair in self]

    def octets(self):
        '''Return column (2nd dimension). Octets for all threads'''
        return [pair[1] for pair in self]

    def sum_packets(self):
        '''Return column (2nd dimension). Sum of all packets for all threads'''
        return sum(self.packets())

    def sum_octets(self):
        '''Return column (2nd dimension). Sum of all octets for all threads'''
        return sum(self.octets())

class StatsTuple(tuple):
    '''A Combined vector tuple (packets, octets)'''
    def __init__(self, data):
        self.dictionary = {'packets': data[0], 'bytes': data[1]}
        super().__init__()

    def __repr__(self):
        return dict.__repr__(self.dictionary)

    def __getitem__(self, item):
        if isinstance(item, int):
            return tuple.__getitem__(self, item)
        if item == 'packets':
            return tuple.__getitem__(self, 0)
        return tuple.__getitem__(self, 1)

class StatsSimpleList(list):
    '''Simple Counters 2-dimensional by thread by index of packets'''

    def __getitem__(self, item):
        '''Supports partial numpy style 2d support. Slice by column [:,1]'''
        if isinstance(item, int):
            return list.__getitem__(self, item)
        return SimpleList([row[item[1]] for row in self])

class SimpleList(list):
    '''Simple counter'''

    def sum(self):
        '''Sum the vector'''
        return sum(self)

class StatsEntry():
    '''An individual stats entry'''
    # pylint: disable=unused-argument,no-self-use

    def __init__(self, stattype, statvalue):
        self.type = stattype
        self.value = statvalue

        if stattype == 1:
            self.function = self.scalar
        elif stattype == 2:
            self.function = self.simple
        elif stattype == 3:
            self.function = self.combined
        elif stattype == 4:
            self.function = self.error
        elif stattype == 5:
            self.function = self.name
        elif stattype == 7:
            self.function = self.symlink
        else:
            self.function = self.illegal

    def illegal(self, stats):
        '''Invalid or unknown counter type'''
        return None

    def scalar(self, stats):
        '''Scalar counter'''
        return self.value

    def simple(self, stats):
        '''Simple counter'''
        counter = StatsSimpleList()
        for threads in StatsVector(stats, self.value, 'P'):
            clist = [v[0] for v in StatsVector(stats, threads[0], 'Q')]
            counter.append(clist)
        return counter

    def combined(self, stats):
        '''Combined counter'''
        counter = StatsCombinedList()
        for threads in StatsVector(stats, self.value, 'P'):
            clist = [StatsTuple(cnt) for cnt in StatsVector(stats, threads[0], 'QQ')]
            counter.append(clist)
        return counter

    def error(self, stats):
        '''Error counter'''
        counter = SimpleList()
        for clist in stats.error_vectors:
            counter.append(clist[self.value])
        return counter

    def name(self, stats):
        '''Name counter'''
        counter = []
        for name in StatsVector(stats, self.value, 'P'):
            if name[0]:
                counter.append(get_string(stats, name[0]))
        return counter

    SYMLINK_FMT1 = Struct('II')
    SYMLINK_FMT2 = Struct('Q')
    def symlink(self, stats):
        '''Symlink counter'''
        b = self.SYMLINK_FMT2.pack(self.value)
        index1, index2 = self.SYMLINK_FMT1.unpack(b)
        name = stats.directory_by_idx[index1]
        return stats[name][:,index2]

    def get_counter(self, stats):
        '''Return a list of counters'''
        if stats:
            return self.function(stats)

class TestStats(unittest.TestCase):
    '''Basic statseg tests'''

    def setUp(self):
        '''Connect to statseg'''
        self.stat = VPPStats()
        self.stat.connect()
        self.profile = cProfile.Profile()
        self.profile.enable()

    def tearDown(self):
        '''Disconnect from statseg'''
        self.stat.disconnect()
        profile = Stats(self.profile)
        profile.strip_dirs()
        profile.sort_stats('cumtime')
        profile.print_stats()
        print("\n--->>>")

    def test_counters(self):
        '''Test access to statseg'''

        print('/err/abf-input-ip4/missed', self.stat['/err/abf-input-ip4/missed'])
        print('/sys/heartbeat', self.stat['/sys/heartbeat'])
        print('/if/names', self.stat['/if/names'])
        print('/if/rx-miss', self.stat['/if/rx-miss'])
        print('/if/rx-miss', self.stat['/if/rx-miss'][1])
        print('/nat44-ed/out2in/slowpath/drops', self.stat['/nat44-ed/out2in/slowpath/drops'])
        print('Set Errors', self.stat.set_errors())
        with self.assertRaises(KeyError):
            print('NO SUCH COUNTER', self.stat['foobar'])
        print('/if/rx', self.stat.get_counter('/if/rx'))
        print('/err/ethernet-input/no error',
              self.stat.get_err_counter('/err/ethernet-input/no error'))

    def test_column(self):
        '''Test column slicing'''

        print('/if/rx-miss', self.stat['/if/rx-miss'])
        print('/if/rx', self.stat['/if/rx'])  # All interfaces for thread #1
        print('/if/rx thread #1', self.stat['/if/rx'][0])  # All interfaces for thread #1
        print('/if/rx thread #1, interface #1',
              self.stat['/if/rx'][0][1])  # All interfaces for thread #1
        print('/if/rx if_index #1', self.stat['/if/rx'][:, 1])
        print('/if/rx if_index #1 packets', self.stat['/if/rx'][:, 1].packets())
        print('/if/rx if_index #1 packets', self.stat['/if/rx'][:, 1].sum_packets())
        print('/if/rx if_index #1 packets', self.stat['/if/rx'][:, 1].octets())
        print('/if/rx-miss', self.stat['/if/rx-miss'])
        print('/if/rx-miss if_index #1 packets', self.stat['/if/rx-miss'][:, 1].sum())
        print('/if/rx if_index #1 packets', self.stat['/if/rx'][0][1]['packets'])

    def test_error(self):
        '''Test the error vector'''

        print('/err/ethernet-input', self.stat['/err/ethernet-input/no error'])
        print('/err/nat44-ei-ha/pkts-processed', self.stat['/err/nat44-ei-ha/pkts-processed'])
        print('/err/ethernet-input', self.stat.get_err_counter('/err/ethernet-input/no error'))
        print('/err/ethernet-input', self.stat['/err/ethernet-input/no error'].sum())

    def test_nat44(self):
        '''Test the nat counters'''

        print('/nat44-ei/ha/del-event-recv', self.stat['/nat44-ei/ha/del-event-recv'])
        print('/err/nat44-ei-ha/pkts-processed', self.stat['/err/nat44-ei-ha/pkts-processed'].sum())

    def test_legacy(self):
        '''Legacy interface'''
        directory = self.stat.ls(["^/if", "/err/ip4-input", "/sys/node/ip4-input"])
        data = self.stat.dump(directory)
        print(data)
        print('Looking up sys node')
        directory = self.stat.ls(["^/sys/node"])
        print('Dumping sys node')
        data = self.stat.dump(directory)
        print(data)
        directory = self.stat.ls(["^/foobar"])
        data = self.stat.dump(directory)
        print(data)

    def test_sys_nodes(self):
        '''Test /sys/nodes'''
        counters = self.stat.ls('^/sys/node')
        print('COUNTERS:', counters)
        print('/sys/node', self.stat.dump(counters))
        print('/net/route/to', self.stat['/net/route/to'])

    def test_symlink(self):
        '''Symbolic links'''
        print('/interface/local0/rx', self.stat['/interfaces/local0/rx'])
        print('/sys/nodes/unix-epoll-input', self.stat['/nodes/unix-epoll-input/calls'])

if __name__ == '__main__':
    import cProfile
    from pstats import Stats

    unittest.main()