RecordData.cpp revision 7bd01783a830f72c1245c262a7fd9a199e90aed1 
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 "debug_disable.h"
44#include "debug_log.h"
45#include "DebugData.h"
46#include "RecordData.h"
47
48RecordEntry::RecordEntry() : tid_(gettid()) {
49}
50
51std::string ThreadCompleteEntry::GetString() const {
52  return android::base::StringPrintf("%d: thread_done 0x0\n", tid_);
53}
54
55AllocEntry::AllocEntry(void* pointer) : pointer_(pointer) {
56}
57
58MallocEntry::MallocEntry(void* pointer, size_t size) : AllocEntry(pointer), size_(size) {
59}
60
61std::string MallocEntry::GetString() const {
62  return android::base::StringPrintf("%d: malloc %p %zu\n", tid_, pointer_, size_);
63}
64
65FreeEntry::FreeEntry(void* pointer) : AllocEntry(pointer) {
66}
67
68std::string FreeEntry::GetString() const {
69  return android::base::StringPrintf("%d: free %p\n", tid_, pointer_);
70}
71
72CallocEntry::CallocEntry(void* pointer, size_t nmemb, size_t size)
73    : MallocEntry(pointer, size), nmemb_(nmemb) {
74}
75
76std::string CallocEntry::GetString() const {
77  return android::base::StringPrintf("%d: calloc %p %zu %zu\n", tid_, pointer_, nmemb_, size_);
78}
79
80ReallocEntry::ReallocEntry(void* pointer, size_t size, void* old_pointer)
81    : MallocEntry(pointer, size), old_pointer_(old_pointer) {
82}
83
84std::string ReallocEntry::GetString() const {
85  return android::base::StringPrintf("%d: realloc %p %p %zu\n", tid_, pointer_,
86                                     old_pointer_, size_);
87}
88
89// posix_memalign, memalgin, pvalloc, valloc all recorded with this class.
90MemalignEntry::MemalignEntry(void* pointer, size_t size, size_t alignment)
91    : MallocEntry(pointer, size), alignment_(alignment) {
92}
93
94std::string MemalignEntry::GetString() const {
95  return android::base::StringPrintf("%d: memalign %p %zu %zu\n", tid_, pointer_,
96                                     alignment_, size_);
97}
98
99struct ThreadData {
100  ThreadData(RecordData* record_data, ThreadCompleteEntry* entry) : record_data(record_data), entry(entry) {}
101  RecordData* record_data;
102  ThreadCompleteEntry* entry;
103  size_t count = 0;
104};
105
106static void ThreadKeyDelete(void* data) {
107  ThreadData* thread_data = reinterpret_cast<ThreadData*>(data);
108
109  thread_data->count++;
110
111  // This should be the last time we are called.
112  if (thread_data->count == 4) {
113    ScopedDisableDebugCalls disable;
114
115    thread_data->record_data->AddEntryOnly(thread_data->entry);
116    delete thread_data;
117  } else {
118    pthread_setspecific(thread_data->record_data->key(), data);
119  }
120}
121
122static void RecordDump(int, siginfo_t*, void*) {
123  // It's not necessarily safe to do the dump here, instead wait for the
124  // next allocation call to do the dump.
125  g_debug->record->SetToDump();
126}
127
128void RecordData::Dump() {
129  std::lock_guard<std::mutex> lock(dump_lock_);
130
131  // Make it so that no more entries can be added while dumping.
132  unsigned int last_entry_index = cur_index_.exchange(static_cast<unsigned int>(num_entries_));
133  if (dump_ == false) {
134    // Multiple Dump() calls from different threads, and we lost. Do nothing.
135    return;
136  }
137
138  // cur_index_ keeps getting incremented even if we hit the num_entries_.
139  // If that happens, cap the entries to dump by num_entries_.
140  if (last_entry_index > num_entries_) {
141    last_entry_index = num_entries_;
142  }
143
144  int dump_fd = open(dump_file_.c_str(), O_WRONLY | O_CREAT | O_TRUNC | O_CLOEXEC | O_NOFOLLOW,
145                     0755);
146  if (dump_fd != -1) {
147    for (size_t i = 0; i < last_entry_index; i++) {
148      std::string line = entries_[i]->GetString();
149      ssize_t bytes = write(dump_fd, line.c_str(), line.length());
150      if (bytes == -1 || static_cast<size_t>(bytes) != line.length()) {
151        error_log("Failed to write record alloc information: %s", strerror(errno));
152        // Free all of the rest of the errors, we don't have any way
153        // to dump a partial list of the entries.
154        for (i++; i < last_entry_index; i++) {
155          delete entries_[i];
156          entries_[i] = nullptr;
157        }
158        break;
159      }
160      delete entries_[i];
161      entries_[i] = nullptr;
162    }
163    close(dump_fd);
164
165    // Mark the entries dumped.
166    cur_index_ = 0U;
167  } else {
168    error_log("Cannot create record alloc file %s: %s", dump_file_.c_str(), strerror(errno));
169    // Since we couldn't create the file, reset the entries dumped back
170    // to the original value.
171    cur_index_ = last_entry_index;
172  }
173
174  dump_ = false;
175}
176
177RecordData::RecordData() {
178  pthread_key_create(&key_, ThreadKeyDelete);
179}
180
181bool RecordData::Initialize(const Config& config) {
182  struct sigaction dump_act;
183  memset(&dump_act, 0, sizeof(dump_act));
184
185  dump_act.sa_sigaction = RecordDump;
186  dump_act.sa_flags = SA_RESTART | SA_SIGINFO | SA_ONSTACK;
187  sigemptyset(&dump_act.sa_mask);
188  if (sigaction(config.record_allocs_signal, &dump_act, nullptr) != 0) {
189    error_log("Unable to set up record dump signal function: %s", strerror(errno));
190    return false;
191  }
192  pthread_setspecific(key_, nullptr);
193
194  info_log("%s: Run: 'kill -%d %d' to dump the allocation records.", getprogname(),
195           config.record_allocs_signal, getpid());
196
197  num_entries_ = config.record_allocs_num_entries;
198  entries_ = new const RecordEntry*[num_entries_];
199  cur_index_ = 0;
200  dump_ = false;
201  dump_file_ = config.record_allocs_file;
202
203  return true;
204}
205
206RecordData::~RecordData() {
207  delete [] entries_;
208  pthread_key_delete(key_);
209}
210
211void RecordData::AddEntryOnly(const RecordEntry* entry) {
212  unsigned int entry_index = cur_index_.fetch_add(1);
213  if (entry_index < num_entries_) {
214    entries_[entry_index] = entry;
215  }
216}
217
218void RecordData::AddEntry(const RecordEntry* entry) {
219  void* data = pthread_getspecific(key_);
220  if (data == nullptr) {
221    ThreadData* thread_data = new ThreadData(this, new ThreadCompleteEntry());
222    pthread_setspecific(key_, thread_data);
223  }
224
225  AddEntryOnly(entry);
226
227  // Check to see if it's time to dump the entries.
228  if (dump_) {
229    Dump();
230  }
231}
232