1 /*
2  * Copyright (C) 2016 The Android Open Source Project
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  *  * Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  *  * Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in
12  *    the documentation and/or other materials provided with the
13  *    distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
18  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
19  * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
25  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <errno.h>
30 #include <fcntl.h>
31 #include <pthread.h>
32 #include <stdatomic.h>
33 #include <stdint.h>
34 #include <stdio.h>
35 #include <stdlib.h>
36 #include <sys/types.h>
37 
38 #include <mutex>
39 
40 #include <android-base/stringprintf.h>
41 
42 #include "Config.h"
43 #include "DebugData.h"
44 #include "RecordData.h"
45 #include "debug_disable.h"
46 #include "debug_log.h"
47 
RecordEntry()48 RecordEntry::RecordEntry() : tid_(gettid()) {
49 }
50 
GetString() const51 std::string ThreadCompleteEntry::GetString() const {
52   return android::base::StringPrintf("%d: thread_done 0x0\n", tid_);
53 }
54 
AllocEntry(void * pointer)55 AllocEntry::AllocEntry(void* pointer) : pointer_(pointer) {}
56 
MallocEntry(void * pointer,size_t size)57 MallocEntry::MallocEntry(void* pointer, size_t size) : AllocEntry(pointer), size_(size) {}
58 
GetString() const59 std::string MallocEntry::GetString() const {
60   return android::base::StringPrintf("%d: malloc %p %zu\n", tid_, pointer_, size_);
61 }
62 
FreeEntry(void * pointer)63 FreeEntry::FreeEntry(void* pointer) : AllocEntry(pointer) {}
64 
GetString() const65 std::string FreeEntry::GetString() const {
66   return android::base::StringPrintf("%d: free %p\n", tid_, pointer_);
67 }
68 
CallocEntry(void * pointer,size_t nmemb,size_t size)69 CallocEntry::CallocEntry(void* pointer, size_t nmemb, size_t size)
70     : MallocEntry(pointer, size), nmemb_(nmemb) {}
71 
GetString() const72 std::string CallocEntry::GetString() const {
73   return android::base::StringPrintf("%d: calloc %p %zu %zu\n", tid_, pointer_, nmemb_, size_);
74 }
75 
ReallocEntry(void * pointer,size_t size,void * old_pointer)76 ReallocEntry::ReallocEntry(void* pointer, size_t size, void* old_pointer)
77     : MallocEntry(pointer, size), old_pointer_(old_pointer) {}
78 
GetString() const79 std::string ReallocEntry::GetString() const {
80   return android::base::StringPrintf("%d: realloc %p %p %zu\n", tid_, pointer_, old_pointer_, size_);
81 }
82 
83 // aligned_alloc, posix_memalign, memalign, pvalloc, valloc all recorded with this class.
MemalignEntry(void * pointer,size_t size,size_t alignment)84 MemalignEntry::MemalignEntry(void* pointer, size_t size, size_t alignment)
85     : MallocEntry(pointer, size), alignment_(alignment) {}
86 
GetString() const87 std::string MemalignEntry::GetString() const {
88   return android::base::StringPrintf("%d: memalign %p %zu %zu\n", tid_, pointer_, alignment_, size_);
89 }
90 
91 struct ThreadData {
ThreadDataThreadData92   ThreadData(RecordData* record_data, ThreadCompleteEntry* entry)
93       : record_data(record_data), entry(entry) {}
94   RecordData* record_data;
95   ThreadCompleteEntry* entry;
96   size_t count = 0;
97 };
98 
ThreadKeyDelete(void * data)99 static void ThreadKeyDelete(void* data) {
100   ThreadData* thread_data = reinterpret_cast<ThreadData*>(data);
101 
102   thread_data->count++;
103 
104   // This should be the last time we are called.
105   if (thread_data->count == 4) {
106     ScopedDisableDebugCalls disable;
107 
108     thread_data->record_data->AddEntryOnly(thread_data->entry);
109     delete thread_data;
110   } else {
111     pthread_setspecific(thread_data->record_data->key(), data);
112   }
113 }
114 
RecordDump(int,siginfo_t *,void *)115 static void RecordDump(int, siginfo_t*, void*) {
116   // It's not necessarily safe to do the dump here, instead wait for the
117   // next allocation call to do the dump.
118   g_debug->record->SetToDump();
119 }
120 
Dump()121 void RecordData::Dump() {
122   std::lock_guard<std::mutex> lock(dump_lock_);
123 
124   // Make it so that no more entries can be added while dumping.
125   unsigned int last_entry_index = cur_index_.exchange(static_cast<unsigned int>(num_entries_));
126   if (dump_ == false) {
127     // Multiple Dump() calls from different threads, and we lost. Do nothing.
128     return;
129   }
130 
131   // cur_index_ keeps getting incremented even if we hit the num_entries_.
132   // If that happens, cap the entries to dump by num_entries_.
133   if (last_entry_index > num_entries_) {
134     last_entry_index = num_entries_;
135   }
136 
137   int dump_fd =
138       open(dump_file_.c_str(), O_WRONLY | O_CREAT | O_TRUNC | O_CLOEXEC | O_NOFOLLOW, 0755);
139   if (dump_fd != -1) {
140     for (size_t i = 0; i < last_entry_index; i++) {
141       std::string line = entries_[i]->GetString();
142       ssize_t bytes = write(dump_fd, line.c_str(), line.length());
143       if (bytes == -1 || static_cast<size_t>(bytes) != line.length()) {
144         error_log("Failed to write record alloc information: %s", strerror(errno));
145         // Free all of the rest of the errors, we don't have any way
146         // to dump a partial list of the entries.
147         for (i++; i < last_entry_index; i++) {
148           delete entries_[i];
149           entries_[i] = nullptr;
150         }
151         break;
152       }
153       delete entries_[i];
154       entries_[i] = nullptr;
155     }
156     close(dump_fd);
157 
158     // Mark the entries dumped.
159     cur_index_ = 0U;
160   } else {
161     error_log("Cannot create record alloc file %s: %s", dump_file_.c_str(), strerror(errno));
162     // Since we couldn't create the file, reset the entries dumped back
163     // to the original value.
164     cur_index_ = last_entry_index;
165   }
166 
167   dump_ = false;
168 }
169 
RecordData()170 RecordData::RecordData() {
171   pthread_key_create(&key_, ThreadKeyDelete);
172 }
173 
Initialize(const Config & config)174 bool RecordData::Initialize(const Config& config) {
175   struct sigaction64 dump_act = {};
176   dump_act.sa_sigaction = RecordDump;
177   dump_act.sa_flags = SA_RESTART | SA_SIGINFO | SA_ONSTACK;
178   if (sigaction64(config.record_allocs_signal(), &dump_act, nullptr) != 0) {
179     error_log("Unable to set up record dump signal function: %s", strerror(errno));
180     return false;
181   }
182   pthread_setspecific(key_, nullptr);
183 
184   if (config.options() & VERBOSE) {
185     info_log("%s: Run: 'kill -%d %d' to dump the allocation records.", getprogname(),
186              config.record_allocs_signal(), getpid());
187   }
188 
189   num_entries_ = config.record_allocs_num_entries();
190   entries_ = new const RecordEntry*[num_entries_];
191   cur_index_ = 0;
192   dump_ = false;
193   dump_file_ = config.record_allocs_file();
194 
195   return true;
196 }
197 
~RecordData()198 RecordData::~RecordData() {
199   delete[] entries_;
200   pthread_key_delete(key_);
201 }
202 
AddEntryOnly(const RecordEntry * entry)203 void RecordData::AddEntryOnly(const RecordEntry* entry) {
204   unsigned int entry_index = cur_index_.fetch_add(1);
205   if (entry_index < num_entries_) {
206     entries_[entry_index] = entry;
207   }
208 }
209 
AddEntry(const RecordEntry * entry)210 void RecordData::AddEntry(const RecordEntry* entry) {
211   void* data = pthread_getspecific(key_);
212   if (data == nullptr) {
213     ThreadData* thread_data = new ThreadData(this, new ThreadCompleteEntry());
214     pthread_setspecific(key_, thread_data);
215   }
216 
217   AddEntryOnly(entry);
218 
219   // Check to see if it's time to dump the entries.
220   if (dump_) {
221     Dump();
222   }
223 }
224