forked from iovisor/bcc
-
Notifications
You must be signed in to change notification settings - Fork 0
/
BPF.cc
798 lines (692 loc) · 26.1 KB
/
BPF.cc
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
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
/*
* Copyright (c) 2016 Facebook, Inc.
*
* 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
*
* https://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.
*/
#include <linux/bpf.h>
#include <linux/perf_event.h>
#include <unistd.h>
#include <cstdio>
#include <cstring>
#include <exception>
#include <iostream>
#include <memory>
#include <sstream>
#include <utility>
#include <vector>
#include "bcc_exception.h"
#include "bcc_syms.h"
#include "bpf_module.h"
#include "common.h"
#include "libbpf.h"
#include "perf_reader.h"
#include "syms.h"
#include "table_storage.h"
#include "usdt.h"
#include "BPF.h"
namespace ebpf {
std::string uint_to_hex(uint64_t value) {
std::stringstream ss;
ss << std::hex << value;
return ss.str();
}
std::string sanitize_str(std::string str, bool (*validator)(char),
char replacement = '_') {
for (size_t i = 0; i < str.length(); i++)
if (!validator(str[i]))
str[i] = replacement;
return str;
}
StatusTuple BPF::init(const std::string& bpf_program,
const std::vector<std::string>& cflags,
const std::vector<USDT>& usdt) {
std::string all_bpf_program;
usdt_.reserve(usdt.size());
for (const auto& u : usdt) {
usdt_.emplace_back(u);
}
for (auto& u : usdt_) {
TRY2(u.init());
all_bpf_program += u.program_text_;
}
auto flags_len = cflags.size();
const char* flags[flags_len];
for (size_t i = 0; i < flags_len; i++)
flags[i] = cflags[i].c_str();
all_bpf_program += bpf_program;
if (bpf_module_->load_string(all_bpf_program, flags, flags_len) != 0)
return StatusTuple(-1, "Unable to initialize BPF program");
return StatusTuple(0);
};
BPF::~BPF() {
auto res = detach_all();
if (res.code() != 0)
std::cerr << "Failed to detach all probes on destruction: " << std::endl
<< res.msg() << std::endl;
}
StatusTuple BPF::detach_all() {
bool has_error = false;
std::string error_msg;
for (auto& it : kprobes_) {
auto res = detach_kprobe_event(it.first, it.second);
if (res.code() != 0) {
error_msg += "Failed to detach kprobe event " + it.first + ": ";
error_msg += res.msg() + "\n";
has_error = true;
}
}
for (auto& it : uprobes_) {
auto res = detach_uprobe_event(it.first, it.second);
if (res.code() != 0) {
error_msg += "Failed to detach uprobe event " + it.first + ": ";
error_msg += res.msg() + "\n";
has_error = true;
}
}
for (auto& it : tracepoints_) {
auto res = detach_tracepoint_event(it.first, it.second);
if (res.code() != 0) {
error_msg += "Failed to detach Tracepoint " + it.first + ": ";
error_msg += res.msg() + "\n";
has_error = true;
}
}
for (auto& it : perf_buffers_) {
auto res = it.second->close_all_cpu();
if (res.code() != 0) {
error_msg += "Failed to close perf buffer " + it.first + ": ";
error_msg += res.msg() + "\n";
has_error = true;
}
delete it.second;
}
for (auto& it : perf_event_arrays_) {
auto res = it.second->close_all_cpu();
if (res.code() != 0) {
error_msg += "Failed to close perf event array " + it.first + ": ";
error_msg += res.msg() + "\n";
has_error = true;
}
delete it.second;
}
for (auto& it : perf_events_) {
auto res = detach_perf_event_all_cpu(it.second);
if (res.code() != 0) {
error_msg += res.msg() + "\n";
has_error = true;
}
}
for (auto& it : funcs_) {
int res = close(it.second);
if (res != 0) {
error_msg += "Failed to unload BPF program for " + it.first + ": ";
error_msg += std::string(std::strerror(errno)) + "\n";
has_error = true;
}
}
if (has_error)
return StatusTuple(-1, error_msg);
else
return StatusTuple(0);
}
StatusTuple BPF::attach_kprobe(const std::string& kernel_func,
const std::string& probe_func,
uint64_t kernel_func_offset,
bpf_probe_attach_type attach_type) {
std::string probe_event = get_kprobe_event(kernel_func, attach_type);
if (kprobes_.find(probe_event) != kprobes_.end())
return StatusTuple(-1, "kprobe %s already attached", probe_event.c_str());
int probe_fd;
TRY2(load_func(probe_func, BPF_PROG_TYPE_KPROBE, probe_fd));
int res_fd = bpf_attach_kprobe(probe_fd, attach_type, probe_event.c_str(),
kernel_func.c_str(), kernel_func_offset);
if (res_fd < 0) {
TRY2(unload_func(probe_func));
return StatusTuple(-1, "Unable to attach %skprobe for %s using %s",
attach_type_debug(attach_type).c_str(),
kernel_func.c_str(), probe_func.c_str());
}
open_probe_t p = {};
p.perf_event_fd = res_fd;
p.func = probe_func;
kprobes_[probe_event] = std::move(p);
return StatusTuple(0);
}
StatusTuple BPF::attach_uprobe(const std::string& binary_path,
const std::string& symbol,
const std::string& probe_func,
uint64_t symbol_addr,
bpf_probe_attach_type attach_type, pid_t pid) {
std::string module;
uint64_t offset;
TRY2(check_binary_symbol(binary_path, symbol, symbol_addr, module, offset));
std::string probe_event = get_uprobe_event(module, offset, attach_type, pid);
if (uprobes_.find(probe_event) != uprobes_.end())
return StatusTuple(-1, "uprobe %s already attached", probe_event.c_str());
int probe_fd;
TRY2(load_func(probe_func, BPF_PROG_TYPE_KPROBE, probe_fd));
int res_fd = bpf_attach_uprobe(probe_fd, attach_type, probe_event.c_str(),
binary_path.c_str(), offset, pid);
if (res_fd < 0) {
TRY2(unload_func(probe_func));
return StatusTuple(
-1,
"Unable to attach %suprobe for binary %s symbol %s addr %lx using %s\n",
attach_type_debug(attach_type).c_str(), binary_path.c_str(),
symbol.c_str(), symbol_addr, probe_func.c_str());
}
open_probe_t p = {};
p.perf_event_fd = res_fd;
p.func = probe_func;
uprobes_[probe_event] = std::move(p);
return StatusTuple(0);
}
StatusTuple BPF::attach_usdt(const USDT& usdt, pid_t pid) {
for (const auto& u : usdt_) {
if (u == usdt) {
auto& probe = *static_cast<::USDT::Probe*>(u.probe_.get());
if (!probe.enable(u.probe_func_))
return StatusTuple(-1, "Unable to enable USDT " + u.print_name());
bool failed = false;
std::string err_msg;
int cnt = 0;
for (const auto& loc : probe.locations_) {
auto res = attach_uprobe(loc.bin_path_, std::string(), u.probe_func_,
loc.address_, BPF_PROBE_ENTRY, pid);
if (res.code() != 0) {
failed = true;
err_msg += "USDT " + u.print_name() + " at " + loc.bin_path_ +
" address " + std::to_string(loc.address_);
err_msg += ": " + res.msg() + "\n";
break;
}
cnt++;
}
if (failed) {
for (int i = 0; i < cnt; i++) {
auto res =
detach_uprobe(probe.locations_[i].bin_path_, std::string(),
probe.locations_[i].address_, BPF_PROBE_ENTRY, pid);
if (res.code() != 0)
err_msg += "During clean up: " + res.msg() + "\n";
}
return StatusTuple(-1, err_msg);
} else {
return StatusTuple(0);
}
}
}
return StatusTuple(-1, "USDT %s not found", usdt.print_name().c_str());
}
StatusTuple BPF::attach_tracepoint(const std::string& tracepoint,
const std::string& probe_func) {
if (tracepoints_.find(tracepoint) != tracepoints_.end())
return StatusTuple(-1, "Tracepoint %s already attached",
tracepoint.c_str());
auto pos = tracepoint.find(":");
if ((pos == std::string::npos) || (pos != tracepoint.rfind(":")))
return StatusTuple(-1, "Unable to parse Tracepoint %s", tracepoint.c_str());
std::string tp_category = tracepoint.substr(0, pos);
std::string tp_name = tracepoint.substr(pos + 1);
int probe_fd;
TRY2(load_func(probe_func, BPF_PROG_TYPE_TRACEPOINT, probe_fd));
int res_fd =
bpf_attach_tracepoint(probe_fd, tp_category.c_str(), tp_name.c_str());
if (res_fd < 0) {
TRY2(unload_func(probe_func));
return StatusTuple(-1, "Unable to attach Tracepoint %s using %s",
tracepoint.c_str(), probe_func.c_str());
}
open_probe_t p = {};
p.perf_event_fd = res_fd;
p.func = probe_func;
tracepoints_[tracepoint] = std::move(p);
return StatusTuple(0);
}
StatusTuple BPF::attach_perf_event(uint32_t ev_type, uint32_t ev_config,
const std::string& probe_func,
uint64_t sample_period, uint64_t sample_freq,
pid_t pid, int cpu, int group_fd) {
auto ev_pair = std::make_pair(ev_type, ev_config);
if (perf_events_.find(ev_pair) != perf_events_.end())
return StatusTuple(-1, "Perf event type %d config %d already attached",
ev_type, ev_config);
int probe_fd;
TRY2(load_func(probe_func, BPF_PROG_TYPE_PERF_EVENT, probe_fd));
std::vector<int> cpus;
if (cpu >= 0)
cpus.push_back(cpu);
else
cpus = get_online_cpus();
auto fds = new std::vector<std::pair<int, int>>();
fds->reserve(cpus.size());
for (int i : cpus) {
int fd = bpf_attach_perf_event(probe_fd, ev_type, ev_config, sample_period,
sample_freq, pid, i, group_fd);
if (fd < 0) {
for (const auto& it : *fds)
close(it.second);
delete fds;
TRY2(unload_func(probe_func));
return StatusTuple(-1, "Failed to attach perf event type %d config %d",
ev_type, ev_config);
}
fds->emplace_back(i, fd);
}
open_probe_t p = {};
p.func = probe_func;
p.per_cpu_fd = fds;
perf_events_[ev_pair] = std::move(p);
return StatusTuple(0);
}
StatusTuple BPF::attach_perf_event_raw(void* perf_event_attr,
const std::string& probe_func, pid_t pid,
int cpu, int group_fd,
unsigned long extra_flags) {
auto attr = static_cast<struct perf_event_attr*>(perf_event_attr);
auto ev_pair = std::make_pair(attr->type, attr->config);
if (perf_events_.find(ev_pair) != perf_events_.end())
return StatusTuple(-1, "Perf event type %d config %d already attached",
attr->type, attr->config);
int probe_fd;
TRY2(load_func(probe_func, BPF_PROG_TYPE_PERF_EVENT, probe_fd));
std::vector<int> cpus;
if (cpu >= 0)
cpus.push_back(cpu);
else
cpus = get_online_cpus();
auto fds = new std::vector<std::pair<int, int>>();
fds->reserve(cpus.size());
for (int i : cpus) {
int fd = bpf_attach_perf_event_raw(probe_fd, attr, pid, i, group_fd,
extra_flags);
if (fd < 0) {
for (const auto& it : *fds)
close(it.second);
delete fds;
TRY2(unload_func(probe_func));
return StatusTuple(-1, "Failed to attach perf event type %d config %d",
attr->type, attr->config);
}
fds->emplace_back(i, fd);
}
open_probe_t p = {};
p.func = probe_func;
p.per_cpu_fd = fds;
perf_events_[ev_pair] = std::move(p);
return StatusTuple(0);
}
StatusTuple BPF::detach_kprobe(const std::string& kernel_func,
bpf_probe_attach_type attach_type) {
std::string event = get_kprobe_event(kernel_func, attach_type);
auto it = kprobes_.find(event);
if (it == kprobes_.end())
return StatusTuple(-1, "No open %skprobe for %s",
attach_type_debug(attach_type).c_str(),
kernel_func.c_str());
TRY2(detach_kprobe_event(it->first, it->second));
kprobes_.erase(it);
return StatusTuple(0);
}
StatusTuple BPF::detach_uprobe(const std::string& binary_path,
const std::string& symbol, uint64_t symbol_addr,
bpf_probe_attach_type attach_type, pid_t pid) {
std::string module;
uint64_t offset;
TRY2(check_binary_symbol(binary_path, symbol, symbol_addr, module, offset));
std::string event = get_uprobe_event(module, offset, attach_type, pid);
auto it = uprobes_.find(event);
if (it == uprobes_.end())
return StatusTuple(-1, "No open %suprobe for binary %s symbol %s addr %lx",
attach_type_debug(attach_type).c_str(),
binary_path.c_str(), symbol.c_str(), symbol_addr);
TRY2(detach_uprobe_event(it->first, it->second));
uprobes_.erase(it);
return StatusTuple(0);
}
StatusTuple BPF::detach_usdt(const USDT& usdt, pid_t pid) {
for (const auto& u : usdt_) {
if (u == usdt) {
auto& probe = *static_cast<::USDT::Probe*>(u.probe_.get());
bool failed = false;
std::string err_msg;
for (const auto& loc : probe.locations_) {
auto res = detach_uprobe(loc.bin_path_, std::string(), loc.address_,
BPF_PROBE_ENTRY, pid);
if (res.code() != 0) {
failed = true;
err_msg += "USDT " + u.print_name() + " at " + loc.bin_path_ +
" address " + std::to_string(loc.address_);
err_msg += ": " + res.msg() + "\n";
}
}
if (!probe.disable()) {
failed = true;
err_msg += "Unable to disable USDT " + u.print_name();
}
if (failed)
return StatusTuple(-1, err_msg);
else
return StatusTuple(0);
}
}
return StatusTuple(-1, "USDT %s not found", usdt.print_name().c_str());
}
StatusTuple BPF::detach_tracepoint(const std::string& tracepoint) {
auto it = tracepoints_.find(tracepoint);
if (it == tracepoints_.end())
return StatusTuple(-1, "No open Tracepoint %s", tracepoint.c_str());
TRY2(detach_tracepoint_event(it->first, it->second));
tracepoints_.erase(it);
return StatusTuple(0);
}
StatusTuple BPF::detach_perf_event(uint32_t ev_type, uint32_t ev_config) {
auto it = perf_events_.find(std::make_pair(ev_type, ev_config));
if (it == perf_events_.end())
return StatusTuple(-1, "Perf Event type %d config %d not attached", ev_type,
ev_config);
TRY2(detach_perf_event_all_cpu(it->second));
perf_events_.erase(it);
return StatusTuple(0);
}
StatusTuple BPF::detach_perf_event_raw(void* perf_event_attr) {
auto attr = static_cast<struct perf_event_attr*>(perf_event_attr);
return detach_perf_event(attr->type, attr->config);
}
StatusTuple BPF::open_perf_event(const std::string& name, uint32_t type,
uint64_t config) {
if (perf_event_arrays_.find(name) == perf_event_arrays_.end()) {
TableStorage::iterator it;
if (!bpf_module_->table_storage().Find(Path({bpf_module_->id(), name}), it))
return StatusTuple(-1, "open_perf_event: unable to find table_storage %s",
name.c_str());
perf_event_arrays_[name] = new BPFPerfEventArray(it->second);
}
auto table = perf_event_arrays_[name];
TRY2(table->open_all_cpu(type, config));
return StatusTuple(0);
}
StatusTuple BPF::close_perf_event(const std::string& name) {
auto it = perf_event_arrays_.find(name);
if (it == perf_event_arrays_.end())
return StatusTuple(-1, "Perf Event for %s not open", name.c_str());
TRY2(it->second->close_all_cpu());
return StatusTuple(0);
}
StatusTuple BPF::open_perf_buffer(const std::string& name,
perf_reader_raw_cb cb,
perf_reader_lost_cb lost_cb, void* cb_cookie,
int page_cnt) {
if (perf_buffers_.find(name) == perf_buffers_.end()) {
TableStorage::iterator it;
if (!bpf_module_->table_storage().Find(Path({bpf_module_->id(), name}), it))
return StatusTuple(-1,
"open_perf_buffer: unable to find table_storage %s",
name.c_str());
perf_buffers_[name] = new BPFPerfBuffer(it->second);
}
if ((page_cnt & (page_cnt - 1)) != 0)
return StatusTuple(-1, "open_perf_buffer page_cnt must be a power of two");
auto table = perf_buffers_[name];
TRY2(table->open_all_cpu(cb, lost_cb, cb_cookie, page_cnt));
return StatusTuple(0);
}
StatusTuple BPF::close_perf_buffer(const std::string& name) {
auto it = perf_buffers_.find(name);
if (it == perf_buffers_.end())
return StatusTuple(-1, "Perf buffer for %s not open", name.c_str());
TRY2(it->second->close_all_cpu());
return StatusTuple(0);
}
BPFPerfBuffer* BPF::get_perf_buffer(const std::string& name) {
auto it = perf_buffers_.find(name);
return (it == perf_buffers_.end()) ? nullptr : it->second;
}
int BPF::poll_perf_buffer(const std::string& name, int timeout_ms) {
auto it = perf_buffers_.find(name);
if (it == perf_buffers_.end())
return -1;
return it->second->poll(timeout_ms);
}
StatusTuple BPF::load_func(const std::string& func_name, bpf_prog_type type,
int& fd) {
if (funcs_.find(func_name) != funcs_.end()) {
fd = funcs_[func_name];
return StatusTuple(0);
}
uint8_t* func_start = bpf_module_->function_start(func_name);
if (!func_start)
return StatusTuple(-1, "Can't find start of function %s",
func_name.c_str());
size_t func_size = bpf_module_->function_size(func_name);
int log_level = 0;
if (flag_ & DEBUG_BPF_REGISTER_STATE)
log_level = 2;
else if (flag_ & DEBUG_BPF)
log_level = 1;
fd = bpf_prog_load(type, func_name.c_str(),
reinterpret_cast<struct bpf_insn*>(func_start), func_size,
bpf_module_->license(), bpf_module_->kern_version(),
log_level, nullptr, 0);
if (fd < 0)
return StatusTuple(-1, "Failed to load %s: %d", func_name.c_str(), fd);
bpf_module_->annotate_prog_tag(
func_name, fd, reinterpret_cast<struct bpf_insn*>(func_start), func_size);
funcs_[func_name] = fd;
return StatusTuple(0);
}
StatusTuple BPF::unload_func(const std::string& func_name) {
auto it = funcs_.find(func_name);
if (it == funcs_.end())
return StatusTuple(0);
int res = close(it->second);
if (res != 0)
return StatusTuple(-1, "Can't close FD for %s: %d", it->first.c_str(), res);
funcs_.erase(it);
return StatusTuple(0);
}
std::string BPF::get_syscall_fnname(const std::string& name) {
if (syscall_prefix_ == nullptr) {
KSyms ksym;
uint64_t addr;
if (ksym.resolve_name(nullptr, "sys_bpf", &addr))
syscall_prefix_.reset(new std::string("sys_"));
else if (ksym.resolve_name(nullptr, "__x64_sys_bpf", &addr))
syscall_prefix_.reset(new std::string("__x64_sys_"));
else
syscall_prefix_.reset(new std::string());
}
return *syscall_prefix_ + name;
}
StatusTuple BPF::check_binary_symbol(const std::string& binary_path,
const std::string& symbol,
uint64_t symbol_addr,
std::string& module_res,
uint64_t& offset_res) {
bcc_symbol output;
int res = bcc_resolve_symname(binary_path.c_str(), symbol.c_str(),
symbol_addr, -1, nullptr, &output);
if (res < 0)
return StatusTuple(
-1, "Unable to find offset for binary %s symbol %s address %lx",
binary_path.c_str(), symbol.c_str(), symbol_addr);
if (output.module) {
module_res = output.module;
::free(const_cast<char*>(output.module));
} else {
module_res = "";
}
offset_res = output.offset;
return StatusTuple(0);
}
std::string BPF::get_kprobe_event(const std::string& kernel_func,
bpf_probe_attach_type type) {
std::string res = attach_type_prefix(type) + "_";
res += sanitize_str(kernel_func, &BPF::kprobe_event_validator);
return res;
}
BPFProgTable BPF::get_prog_table(const std::string& name) {
TableStorage::iterator it;
if (bpf_module_->table_storage().Find(Path({bpf_module_->id(), name}), it))
return BPFProgTable(it->second);
return BPFProgTable({});
}
BPFCgroupArray BPF::get_cgroup_array(const std::string& name) {
TableStorage::iterator it;
if (bpf_module_->table_storage().Find(Path({bpf_module_->id(), name}), it))
return BPFCgroupArray(it->second);
return BPFCgroupArray({});
}
BPFStackTable BPF::get_stack_table(const std::string& name, bool use_debug_file,
bool check_debug_file_crc) {
TableStorage::iterator it;
if (bpf_module_->table_storage().Find(Path({bpf_module_->id(), name}), it))
return BPFStackTable(it->second, use_debug_file, check_debug_file_crc);
return BPFStackTable({}, use_debug_file, check_debug_file_crc);
}
std::string BPF::get_uprobe_event(const std::string& binary_path,
uint64_t offset, bpf_probe_attach_type type,
pid_t pid) {
std::string res = attach_type_prefix(type) + "_";
res += sanitize_str(binary_path, &BPF::uprobe_path_validator);
res += "_0x" + uint_to_hex(offset);
if (pid != -1)
res += "_" + std::to_string(pid);
return res;
}
StatusTuple BPF::detach_kprobe_event(const std::string& event,
open_probe_t& attr) {
bpf_close_perf_event_fd(attr.perf_event_fd);
TRY2(unload_func(attr.func));
if (bpf_detach_kprobe(event.c_str()) < 0)
return StatusTuple(-1, "Unable to detach kprobe %s", event.c_str());
return StatusTuple(0);
}
StatusTuple BPF::detach_uprobe_event(const std::string& event,
open_probe_t& attr) {
bpf_close_perf_event_fd(attr.perf_event_fd);
TRY2(unload_func(attr.func));
if (bpf_detach_uprobe(event.c_str()) < 0)
return StatusTuple(-1, "Unable to detach uprobe %s", event.c_str());
return StatusTuple(0);
}
StatusTuple BPF::detach_tracepoint_event(const std::string& tracepoint,
open_probe_t& attr) {
bpf_close_perf_event_fd(attr.perf_event_fd);
TRY2(unload_func(attr.func));
// TODO: bpf_detach_tracepoint currently does nothing.
return StatusTuple(0);
}
StatusTuple BPF::detach_perf_event_all_cpu(open_probe_t& attr) {
bool has_error = false;
std::string err_msg;
for (const auto& it : *attr.per_cpu_fd) {
int res = bpf_close_perf_event_fd(it.second);
if (res != 0) {
has_error = true;
err_msg += "Failed to close perf event FD " + std::to_string(it.second) +
" For CPU " + std::to_string(it.first) + ": ";
err_msg += std::string(std::strerror(errno)) + "\n";
}
}
delete attr.per_cpu_fd;
TRY2(unload_func(attr.func));
if (has_error)
return StatusTuple(-1, err_msg);
return StatusTuple(0);
}
USDT::USDT(const std::string& binary_path, const std::string& provider,
const std::string& name, const std::string& probe_func)
: initialized_(false),
binary_path_(binary_path),
pid_(-1),
provider_(provider),
name_(name),
probe_func_(probe_func) {}
USDT::USDT(pid_t pid, const std::string& provider, const std::string& name,
const std::string& probe_func)
: initialized_(false),
binary_path_(),
pid_(pid),
provider_(provider),
name_(name),
probe_func_(probe_func) {}
USDT::USDT(const std::string& binary_path, pid_t pid,
const std::string& provider, const std::string& name,
const std::string& probe_func)
: initialized_(false),
binary_path_(binary_path),
pid_(pid),
provider_(provider),
name_(name),
probe_func_(probe_func) {}
USDT::USDT(const USDT& usdt)
: initialized_(false),
binary_path_(usdt.binary_path_),
pid_(usdt.pid_),
provider_(usdt.provider_),
name_(usdt.name_),
probe_func_(usdt.probe_func_) {}
USDT::USDT(USDT&& usdt) noexcept
: initialized_(usdt.initialized_),
binary_path_(std::move(usdt.binary_path_)),
pid_(usdt.pid_),
provider_(std::move(usdt.provider_)),
name_(std::move(usdt.name_)),
probe_func_(std::move(usdt.probe_func_)),
probe_(std::move(usdt.probe_)),
program_text_(std::move(usdt.program_text_)) {
usdt.initialized_ = false;
}
bool USDT::operator==(const USDT& other) const {
return (provider_ == other.provider_) && (name_ == other.name_) &&
(binary_path_ == other.binary_path_) && (pid_ == other.pid_) &&
(probe_func_ == other.probe_func_);
}
StatusTuple USDT::init() {
std::unique_ptr<::USDT::Context> ctx;
if (!binary_path_.empty() && pid_ > 0)
ctx.reset(new ::USDT::Context(pid_, binary_path_));
else if (!binary_path_.empty())
ctx.reset(new ::USDT::Context(binary_path_));
else if (pid_ > 0)
ctx.reset(new ::USDT::Context(pid_));
else
return StatusTuple(-1, "No valid Binary Path or PID provided");
if (!ctx->loaded())
return StatusTuple(-1, "Unable to load USDT " + print_name());
auto deleter = [](void* probe) { delete static_cast<::USDT::Probe*>(probe); };
for (auto& p : ctx->probes_) {
if (p->provider_ == provider_ && p->name_ == name_) {
// Take ownership of the probe that we are interested in, and avoid it
// being destrcuted when we destruct the USDT::Context instance
probe_ = std::unique_ptr<void, std::function<void(void*)>>(p.release(),
deleter);
p.swap(ctx->probes_.back());
ctx->probes_.pop_back();
break;
}
}
if (!probe_)
return StatusTuple(-1, "Unable to find USDT " + print_name());
ctx.reset(nullptr);
auto& probe = *static_cast<::USDT::Probe*>(probe_.get());
std::ostringstream stream;
if (!probe.usdt_getarg(stream, probe_func_))
return StatusTuple(
-1, "Unable to generate program text for USDT " + print_name());
program_text_ = ::USDT::USDT_PROGRAM_HEADER + stream.str();
initialized_ = true;
return StatusTuple(0);
}
} // namespace ebpf