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
|
/*
*
* Copyright 2018, The Android Open Source Project
*
* 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.
*/
#include "symbolizer.h"
#include <map>
#include <memory>
#include <unordered_map>
#include <android-base/logging.h>
#include "build_id.h"
#include "read_elf.h"
namespace perfprofd {
namespace {
struct SimpleperfSymbolizer : public Symbolizer {
// For simplicity, we assume non-overlapping symbols.
struct Symbol {
std::string name;
uint64_t length;
};
using SymbolMap = std::map<uint64_t, Symbol>;
std::string Decode(const std::string& dso, uint64_t address) override {
auto it = dsos.find(dso);
if (it == dsos.end()) {
LoadDso(dso);
it = dsos.find(dso);
DCHECK(it != dsos.end());
}
const SymbolMap& map = it->second;
if (map.empty()) {
return "";
}
auto upper_bound = map.upper_bound(address);
if (upper_bound == map.begin()) {
// Nope, not in the map.
return "";
}
upper_bound--;
if (upper_bound->first + upper_bound->second.length > address) {
// This element covers the given address, return its name.
return upper_bound->second.name;
}
return "";
}
void LoadDso(const std::string& dso) {
SymbolMap data;
auto callback = [&data](const ElfFileSymbol& sym) {
if (sym.is_func) {
Symbol symbol;
symbol.name = sym.name;
symbol.length = sym.len;
if (sym.len == 0) {
LOG(ERROR) << "Symbol size is zero for " << sym.name;
}
data.emplace(sym.vaddr, std::move(symbol));
}
};
ElfStatus status = ParseSymbolsFromElfFile(dso, BuildId(), callback);
if (status != ElfStatus::NO_ERROR) {
LOG(WARNING) << "Could not parse dso " << dso << ": " << status;
}
dsos.emplace(dso, std::move(data));
}
bool GetMinExecutableVAddr(const std::string& dso, uint64_t* addr) override {
ElfStatus status = ReadMinExecutableVirtualAddressFromElfFile(dso, BuildId(), addr);
return status == ElfStatus::NO_ERROR;
}
std::unordered_map<std::string, SymbolMap> dsos;
};
} // namespace
std::unique_ptr<Symbolizer> CreateELFSymbolizer() {
return std::unique_ptr<Symbolizer>(new SimpleperfSymbolizer());
}
} // namespace perfprofd
|
