1 | //===-- OProfileJITEventListener.cpp - Tell OProfile about JITted code ----===// |
2 | // |
3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
4 | // See https://llvm.org/LICENSE.txt for license information. |
5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
6 | // |
7 | //===----------------------------------------------------------------------===// |
8 | // |
9 | // This file defines a JITEventListener object that uses OProfileWrapper to tell |
10 | // oprofile about JITted functions, including source line information. |
11 | // |
12 | //===----------------------------------------------------------------------===// |
13 | |
14 | #include "llvm-c/ExecutionEngine.h" |
15 | #include "llvm/CodeGen/MachineFunction.h" |
16 | #include "llvm/Config/config.h" |
17 | #include "llvm/DebugInfo/DWARF/DWARFContext.h" |
18 | #include "llvm/ExecutionEngine/JITEventListener.h" |
19 | #include "llvm/ExecutionEngine/OProfileWrapper.h" |
20 | #include "llvm/ExecutionEngine/RuntimeDyld.h" |
21 | #include "llvm/IR/DebugInfo.h" |
22 | #include "llvm/IR/Function.h" |
23 | #include "llvm/Object/ObjectFile.h" |
24 | #include "llvm/Object/SymbolSize.h" |
25 | #include "llvm/Support/Debug.h" |
26 | #include "llvm/Support/Errno.h" |
27 | #include "llvm/Support/raw_ostream.h" |
28 | #include <dirent.h> |
29 | #include <fcntl.h> |
30 | |
31 | using namespace llvm; |
32 | using namespace llvm::object; |
33 | |
34 | #define DEBUG_TYPE "oprofile-jit-event-listener" |
35 | |
36 | namespace { |
37 | |
38 | class OProfileJITEventListener : public JITEventListener { |
39 | std::unique_ptr<OProfileWrapper> Wrapper; |
40 | |
41 | void initialize(); |
42 | std::map<ObjectKey, OwningBinary<ObjectFile>> DebugObjects; |
43 | |
44 | public: |
45 | OProfileJITEventListener(std::unique_ptr<OProfileWrapper> LibraryWrapper) |
46 | : Wrapper(std::move(LibraryWrapper)) { |
47 | initialize(); |
48 | } |
49 | |
50 | ~OProfileJITEventListener(); |
51 | |
52 | void notifyObjectLoaded(ObjectKey Key, const ObjectFile &Obj, |
53 | const RuntimeDyld::LoadedObjectInfo &L) override; |
54 | |
55 | void notifyFreeingObject(ObjectKey Key) override; |
56 | }; |
57 | |
58 | void OProfileJITEventListener::initialize() { |
59 | if (!Wrapper->op_open_agent()) { |
60 | const std::string err_str = sys::StrError(); |
61 | LLVM_DEBUG(dbgs() << "Failed to connect to OProfile agent: " << err_str |
62 | << "\n" ); |
63 | } else { |
64 | LLVM_DEBUG(dbgs() << "Connected to OProfile agent.\n" ); |
65 | } |
66 | } |
67 | |
68 | OProfileJITEventListener::~OProfileJITEventListener() { |
69 | if (Wrapper->isAgentAvailable()) { |
70 | if (Wrapper->op_close_agent() == -1) { |
71 | const std::string err_str = sys::StrError(); |
72 | LLVM_DEBUG(dbgs() << "Failed to disconnect from OProfile agent: " |
73 | << err_str << "\n" ); |
74 | } else { |
75 | LLVM_DEBUG(dbgs() << "Disconnected from OProfile agent.\n" ); |
76 | } |
77 | } |
78 | } |
79 | |
80 | void OProfileJITEventListener::notifyObjectLoaded( |
81 | ObjectKey Key, const ObjectFile &Obj, |
82 | const RuntimeDyld::LoadedObjectInfo &L) { |
83 | if (!Wrapper->isAgentAvailable()) { |
84 | return; |
85 | } |
86 | |
87 | OwningBinary<ObjectFile> DebugObjOwner = L.getObjectForDebug(Obj); |
88 | const ObjectFile &DebugObj = *DebugObjOwner.getBinary(); |
89 | std::unique_ptr<DIContext> Context = DWARFContext::create(Obj: DebugObj); |
90 | |
91 | // Use symbol info to iterate functions in the object. |
92 | for (const std::pair<SymbolRef, uint64_t> &P : computeSymbolSizes(O: DebugObj)) { |
93 | SymbolRef Sym = P.first; |
94 | if (!Sym.getType() || *Sym.getType() != SymbolRef::ST_Function) |
95 | continue; |
96 | |
97 | Expected<StringRef> NameOrErr = Sym.getName(); |
98 | if (!NameOrErr) |
99 | continue; |
100 | StringRef Name = *NameOrErr; |
101 | Expected<uint64_t> AddrOrErr = Sym.getAddress(); |
102 | if (!AddrOrErr) |
103 | continue; |
104 | uint64_t Addr = *AddrOrErr; |
105 | uint64_t Size = P.second; |
106 | |
107 | if (Wrapper->op_write_native_code(name: Name.data(), addr: Addr, code: (void *)Addr, size: Size) == |
108 | -1) { |
109 | LLVM_DEBUG(dbgs() << "Failed to tell OProfile about native function " |
110 | << Name << " at [" << (void *)Addr << "-" |
111 | << ((char *)Addr + Size) << "]\n" ); |
112 | continue; |
113 | } |
114 | |
115 | DILineInfoTable Lines = Context->getLineInfoForAddressRange(Addr, Size); |
116 | size_t i = 0; |
117 | size_t num_entries = Lines.size(); |
118 | struct debug_line_info *debug_line; |
119 | debug_line = (struct debug_line_info *)calloc( |
120 | num_entries, sizeof(struct debug_line_info)); |
121 | |
122 | for (auto& It : Lines) { |
123 | debug_line[i].vma = (unsigned long)It.first; |
124 | debug_line[i].lineno = It.second.Line; |
125 | debug_line[i].filename = |
126 | const_cast<char *>(Lines.front().second.FileName.c_str()); |
127 | ++i; |
128 | } |
129 | |
130 | if (Wrapper->op_write_debug_line_info(code: (void *)Addr, num_entries, |
131 | info: debug_line) == -1) { |
132 | LLVM_DEBUG(dbgs() << "Failed to tell OProfiler about debug object at [" |
133 | << (void *)Addr << "-" << ((char *)Addr + Size) |
134 | << "]\n" ); |
135 | continue; |
136 | } |
137 | } |
138 | |
139 | DebugObjects[Key] = std::move(DebugObjOwner); |
140 | } |
141 | |
142 | void OProfileJITEventListener::notifyFreeingObject(ObjectKey Key) { |
143 | if (Wrapper->isAgentAvailable()) { |
144 | |
145 | // If there was no agent registered when the original object was loaded then |
146 | // we won't have created a debug object for it, so bail out. |
147 | if (DebugObjects.find(x: Key) == DebugObjects.end()) |
148 | return; |
149 | |
150 | const ObjectFile &DebugObj = *DebugObjects[Key].getBinary(); |
151 | |
152 | // Use symbol info to iterate functions in the object. |
153 | for (symbol_iterator I = DebugObj.symbol_begin(), |
154 | E = DebugObj.symbol_end(); |
155 | I != E; ++I) { |
156 | if (I->getType() && *I->getType() == SymbolRef::ST_Function) { |
157 | Expected<uint64_t> AddrOrErr = I->getAddress(); |
158 | if (!AddrOrErr) |
159 | continue; |
160 | uint64_t Addr = *AddrOrErr; |
161 | |
162 | if (Wrapper->op_unload_native_code(addr: Addr) == -1) { |
163 | LLVM_DEBUG( |
164 | dbgs() |
165 | << "Failed to tell OProfile about unload of native function at " |
166 | << (void *)Addr << "\n" ); |
167 | continue; |
168 | } |
169 | } |
170 | } |
171 | } |
172 | |
173 | DebugObjects.erase(x: Key); |
174 | } |
175 | |
176 | } // anonymous namespace. |
177 | |
178 | namespace llvm { |
179 | JITEventListener *JITEventListener::createOProfileJITEventListener() { |
180 | return new OProfileJITEventListener(std::make_unique<OProfileWrapper>()); |
181 | } |
182 | |
183 | } // namespace llvm |
184 | |
185 | LLVMJITEventListenerRef LLVMCreateOProfileJITEventListener(void) |
186 | { |
187 | return wrap(P: JITEventListener::createOProfileJITEventListener()); |
188 | } |
189 | |