1 //===-- memprof_rtl.cpp --------------------------------------------------===//
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 is a part of MemProfiler, a memory profiler.
10 //
11 // Main file of the MemProf run-time library.
12 //===----------------------------------------------------------------------===//
13
14 #include "memprof_allocator.h"
15 #include "memprof_interceptors.h"
16 #include "memprof_interface_internal.h"
17 #include "memprof_internal.h"
18 #include "memprof_mapping.h"
19 #include "memprof_stack.h"
20 #include "memprof_stats.h"
21 #include "memprof_thread.h"
22 #include "sanitizer_common/sanitizer_atomic.h"
23 #include "sanitizer_common/sanitizer_flags.h"
24 #include "sanitizer_common/sanitizer_interface_internal.h"
25 #include "sanitizer_common/sanitizer_libc.h"
26 #include "sanitizer_common/sanitizer_symbolizer.h"
27
28 #include <time.h>
29
30 uptr __memprof_shadow_memory_dynamic_address; // Global interface symbol.
31
32 // Allow the user to specify a profile output file via the binary.
33 SANITIZER_WEAK_ATTRIBUTE char __memprof_profile_filename[1];
34
35 namespace __memprof {
36
MemprofDie()37 static void MemprofDie() {
38 static atomic_uint32_t num_calls;
39 if (atomic_fetch_add(&num_calls, 1, memory_order_relaxed) != 0) {
40 // Don't die twice - run a busy loop.
41 while (1) {
42 internal_sched_yield();
43 }
44 }
45 if (common_flags()->print_module_map >= 1)
46 DumpProcessMap();
47 if (flags()->unmap_shadow_on_exit) {
48 if (kHighShadowEnd)
49 UnmapOrDie((void *)kLowShadowBeg, kHighShadowEnd - kLowShadowBeg);
50 }
51 }
52
MemprofOnDeadlySignal(int signo,void * siginfo,void * context)53 static void MemprofOnDeadlySignal(int signo, void *siginfo, void *context) {
54 // We call StartReportDeadlySignal not HandleDeadlySignal so we get the
55 // deadly signal message to stderr but no writing to the profile output file
56 StartReportDeadlySignal();
57 __memprof_profile_dump();
58 Die();
59 }
60
CheckUnwind()61 static void CheckUnwind() {
62 GET_STACK_TRACE(kStackTraceMax, common_flags()->fast_unwind_on_check);
63 stack.Print();
64 }
65
66 // -------------------------- Globals --------------------- {{{1
67 int memprof_inited;
68 bool memprof_init_is_running;
69 int memprof_timestamp_inited;
70 long memprof_init_timestamp_s;
71
72 uptr kHighMemEnd;
73
74 // -------------------------- Run-time entry ------------------- {{{1
75 // exported functions
76
77 #define MEMPROF_MEMORY_ACCESS_CALLBACK_BODY() __memprof::RecordAccess(addr);
78
79 #define MEMPROF_MEMORY_ACCESS_CALLBACK(type) \
80 extern "C" NOINLINE INTERFACE_ATTRIBUTE void __memprof_##type(uptr addr) { \
81 MEMPROF_MEMORY_ACCESS_CALLBACK_BODY() \
82 }
83
84 MEMPROF_MEMORY_ACCESS_CALLBACK(load)
MEMPROF_MEMORY_ACCESS_CALLBACK(store)85 MEMPROF_MEMORY_ACCESS_CALLBACK(store)
86
87 // Force the linker to keep the symbols for various MemProf interface
88 // functions. We want to keep those in the executable in order to let the
89 // instrumented dynamic libraries access the symbol even if it is not used by
90 // the executable itself. This should help if the build system is removing dead
91 // code at link time.
92 static NOINLINE void force_interface_symbols() {
93 volatile int fake_condition = 0; // prevent dead condition elimination.
94 // clang-format off
95 switch (fake_condition) {
96 case 1: __memprof_record_access(nullptr); break;
97 case 2: __memprof_record_access_range(nullptr, 0); break;
98 }
99 // clang-format on
100 }
101
memprof_atexit()102 static void memprof_atexit() {
103 Printf("MemProfiler exit stats:\n");
104 __memprof_print_accumulated_stats();
105 }
106
InitializeHighMemEnd()107 static void InitializeHighMemEnd() {
108 kHighMemEnd = GetMaxUserVirtualAddress();
109 // Increase kHighMemEnd to make sure it's properly
110 // aligned together with kHighMemBeg:
111 kHighMemEnd |= (GetMmapGranularity() << SHADOW_SCALE) - 1;
112 }
113
PrintAddressSpaceLayout()114 void PrintAddressSpaceLayout() {
115 if (kHighMemBeg) {
116 Printf("|| `[%p, %p]` || HighMem ||\n", (void *)kHighMemBeg,
117 (void *)kHighMemEnd);
118 Printf("|| `[%p, %p]` || HighShadow ||\n", (void *)kHighShadowBeg,
119 (void *)kHighShadowEnd);
120 }
121 Printf("|| `[%p, %p]` || ShadowGap ||\n", (void *)kShadowGapBeg,
122 (void *)kShadowGapEnd);
123 if (kLowShadowBeg) {
124 Printf("|| `[%p, %p]` || LowShadow ||\n", (void *)kLowShadowBeg,
125 (void *)kLowShadowEnd);
126 Printf("|| `[%p, %p]` || LowMem ||\n", (void *)kLowMemBeg,
127 (void *)kLowMemEnd);
128 }
129 Printf("MemToShadow(shadow): %p %p", (void *)MEM_TO_SHADOW(kLowShadowBeg),
130 (void *)MEM_TO_SHADOW(kLowShadowEnd));
131 if (kHighMemBeg) {
132 Printf(" %p %p", (void *)MEM_TO_SHADOW(kHighShadowBeg),
133 (void *)MEM_TO_SHADOW(kHighShadowEnd));
134 }
135 Printf("\n");
136 Printf("malloc_context_size=%zu\n",
137 (uptr)common_flags()->malloc_context_size);
138
139 Printf("SHADOW_SCALE: %d\n", (int)SHADOW_SCALE);
140 Printf("SHADOW_GRANULARITY: %d\n", (int)SHADOW_GRANULARITY);
141 Printf("SHADOW_OFFSET: 0x%zx\n", (uptr)SHADOW_OFFSET);
142 CHECK(SHADOW_SCALE >= 3 && SHADOW_SCALE <= 7);
143 }
144
MemprofInitInternal()145 static void MemprofInitInternal() {
146 if (LIKELY(memprof_inited))
147 return;
148 SanitizerToolName = "MemProfiler";
149 CHECK(!memprof_init_is_running && "MemProf init calls itself!");
150 memprof_init_is_running = true;
151
152 CacheBinaryName();
153
154 // Initialize flags. This must be done early, because most of the
155 // initialization steps look at flags().
156 InitializeFlags();
157
158 AvoidCVE_2016_2143();
159
160 SetMallocContextSize(common_flags()->malloc_context_size);
161
162 InitializeHighMemEnd();
163
164 // Make sure we are not statically linked.
165 MemprofDoesNotSupportStaticLinkage();
166
167 // Install tool-specific callbacks in sanitizer_common.
168 AddDieCallback(MemprofDie);
169 SetCheckUnwindCallback(CheckUnwind);
170
171 // Use profile name specified via the binary itself if it exists, and hasn't
172 // been overrriden by a flag at runtime.
173 if (__memprof_profile_filename[0] != 0 && !common_flags()->log_path)
174 __sanitizer_set_report_path(__memprof_profile_filename);
175 else
176 __sanitizer_set_report_path(common_flags()->log_path);
177
178 __sanitizer::InitializePlatformEarly();
179
180 // Setup internal allocator callback.
181 SetLowLevelAllocateMinAlignment(SHADOW_GRANULARITY);
182
183 InitializeMemprofInterceptors();
184 CheckASLR();
185
186 ReplaceSystemMalloc();
187
188 DisableCoreDumperIfNecessary();
189
190 InitializeShadowMemory();
191
192 TSDInit(PlatformTSDDtor);
193 InstallDeadlySignalHandlers(MemprofOnDeadlySignal);
194
195 InitializeAllocator();
196
197 if (flags()->atexit)
198 Atexit(memprof_atexit);
199
200 InitializeCoverage(common_flags()->coverage, common_flags()->coverage_dir);
201
202 // interceptors
203 InitTlsSize();
204
205 // Create main thread.
206 MemprofThread *main_thread = CreateMainThread();
207 CHECK_EQ(0, main_thread->tid());
208 force_interface_symbols(); // no-op.
209 SanitizerInitializeUnwinder();
210
211 Symbolizer::LateInitialize();
212
213 VReport(1, "MemProfiler Init done\n");
214
215 memprof_init_is_running = false;
216 memprof_inited = 1;
217 }
218
MemprofInitTime()219 void MemprofInitTime() {
220 if (LIKELY(memprof_timestamp_inited))
221 return;
222 timespec ts;
223 clock_gettime(CLOCK_REALTIME, &ts);
224 memprof_init_timestamp_s = ts.tv_sec;
225 memprof_timestamp_inited = 1;
226 }
227
228 // Initialize as requested from some part of MemProf runtime library
229 // (interceptors, allocator, etc).
MemprofInitFromRtl()230 void MemprofInitFromRtl() { MemprofInitInternal(); }
231
232 #if MEMPROF_DYNAMIC
233 // Initialize runtime in case it's LD_PRELOAD-ed into uninstrumented executable
234 // (and thus normal initializers from .preinit_array or modules haven't run).
235
236 class MemprofInitializer {
237 public:
MemprofInitializer()238 MemprofInitializer() { MemprofInitFromRtl(); }
239 };
240
241 static MemprofInitializer memprof_initializer;
242 #endif // MEMPROF_DYNAMIC
243
244 } // namespace __memprof
245
246 // ---------------------- Interface ---------------- {{{1
247 using namespace __memprof;
248
249 // Initialize as requested from instrumented application code.
__memprof_init()250 void __memprof_init() {
251 MemprofInitTime();
252 MemprofInitInternal();
253 }
254
__memprof_preinit()255 void __memprof_preinit() { MemprofInitInternal(); }
256
__memprof_version_mismatch_check_v1()257 void __memprof_version_mismatch_check_v1() {}
258
__memprof_record_access(void const volatile * addr)259 void __memprof_record_access(void const volatile *addr) {
260 __memprof::RecordAccess((uptr)addr);
261 }
262
__memprof_record_access_range(void const volatile * addr,uptr size)263 void __memprof_record_access_range(void const volatile *addr, uptr size) {
264 for (uptr a = (uptr)addr; a < (uptr)addr + size; a += kWordSize)
265 __memprof::RecordAccess(a);
266 }
267
268 extern "C" SANITIZER_INTERFACE_ATTRIBUTE u16
__sanitizer_unaligned_load16(const uu16 * p)269 __sanitizer_unaligned_load16(const uu16 *p) {
270 __memprof_record_access(p);
271 return *p;
272 }
273
274 extern "C" SANITIZER_INTERFACE_ATTRIBUTE u32
__sanitizer_unaligned_load32(const uu32 * p)275 __sanitizer_unaligned_load32(const uu32 *p) {
276 __memprof_record_access(p);
277 return *p;
278 }
279
280 extern "C" SANITIZER_INTERFACE_ATTRIBUTE u64
__sanitizer_unaligned_load64(const uu64 * p)281 __sanitizer_unaligned_load64(const uu64 *p) {
282 __memprof_record_access(p);
283 return *p;
284 }
285
286 extern "C" SANITIZER_INTERFACE_ATTRIBUTE void
__sanitizer_unaligned_store16(uu16 * p,u16 x)287 __sanitizer_unaligned_store16(uu16 *p, u16 x) {
288 __memprof_record_access(p);
289 *p = x;
290 }
291
292 extern "C" SANITIZER_INTERFACE_ATTRIBUTE void
__sanitizer_unaligned_store32(uu32 * p,u32 x)293 __sanitizer_unaligned_store32(uu32 *p, u32 x) {
294 __memprof_record_access(p);
295 *p = x;
296 }
297
298 extern "C" SANITIZER_INTERFACE_ATTRIBUTE void
__sanitizer_unaligned_store64(uu64 * p,u64 x)299 __sanitizer_unaligned_store64(uu64 *p, u64 x) {
300 __memprof_record_access(p);
301 *p = x;
302 }
303