xref: /freebsd/contrib/llvm-project/compiler-rt/lib/asan/asan_stats.cpp (revision fe75646a0234a261c0013bf1840fdac4acaf0cec)
1 //===-- asan_stats.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 AddressSanitizer, an address sanity checker.
10 //
11 // Code related to statistics collected by AddressSanitizer.
12 //===----------------------------------------------------------------------===//
13 #include "asan_interceptors.h"
14 #include "asan_internal.h"
15 #include "asan_stats.h"
16 #include "asan_thread.h"
17 #include "sanitizer_common/sanitizer_allocator_interface.h"
18 #include "sanitizer_common/sanitizer_mutex.h"
19 #include "sanitizer_common/sanitizer_stackdepot.h"
20 
21 namespace __asan {
22 
23 AsanStats::AsanStats() {
24   Clear();
25 }
26 
27 void AsanStats::Clear() {
28   CHECK(REAL(memset));
29   REAL(memset)(this, 0, sizeof(AsanStats));
30 }
31 
32 static void PrintMallocStatsArray(const char *prefix,
33                                   uptr (&array)[kNumberOfSizeClasses]) {
34   Printf("%s", prefix);
35   for (uptr i = 0; i < kNumberOfSizeClasses; i++) {
36     if (!array[i]) continue;
37     Printf("%zu:%zu; ", i, array[i]);
38   }
39   Printf("\n");
40 }
41 
42 void AsanStats::Print() {
43   Printf("Stats: %zuM malloced (%zuM for red zones) by %zu calls\n",
44              malloced>>20, malloced_redzones>>20, mallocs);
45   Printf("Stats: %zuM realloced by %zu calls\n", realloced>>20, reallocs);
46   Printf("Stats: %zuM freed by %zu calls\n", freed>>20, frees);
47   Printf("Stats: %zuM really freed by %zu calls\n",
48              really_freed>>20, real_frees);
49   Printf("Stats: %zuM (%zuM-%zuM) mmaped; %zu maps, %zu unmaps\n",
50              (mmaped-munmaped)>>20, mmaped>>20, munmaped>>20,
51              mmaps, munmaps);
52 
53   PrintMallocStatsArray("  mallocs by size class: ", malloced_by_size);
54   Printf("Stats: malloc large: %zu\n", malloc_large);
55 }
56 
57 void AsanStats::MergeFrom(const AsanStats *stats) {
58   uptr *dst_ptr = reinterpret_cast<uptr*>(this);
59   const uptr *src_ptr = reinterpret_cast<const uptr*>(stats);
60   uptr num_fields = sizeof(*this) / sizeof(uptr);
61   for (uptr i = 0; i < num_fields; i++)
62     dst_ptr[i] += src_ptr[i];
63 }
64 
65 static Mutex print_lock;
66 
67 static AsanStats unknown_thread_stats(LINKER_INITIALIZED);
68 static AsanStats dead_threads_stats(LINKER_INITIALIZED);
69 static Mutex dead_threads_stats_lock;
70 // Required for malloc_zone_statistics() on OS X. This can't be stored in
71 // per-thread AsanStats.
72 static uptr max_malloced_memory;
73 
74 static void MergeThreadStats(ThreadContextBase *tctx_base, void *arg) {
75   AsanStats *accumulated_stats = reinterpret_cast<AsanStats*>(arg);
76   AsanThreadContext *tctx = static_cast<AsanThreadContext*>(tctx_base);
77   if (AsanThread *t = tctx->thread)
78     accumulated_stats->MergeFrom(&t->stats());
79 }
80 
81 static void GetAccumulatedStats(AsanStats *stats) {
82   stats->Clear();
83   {
84     ThreadRegistryLock l(&asanThreadRegistry());
85     asanThreadRegistry()
86         .RunCallbackForEachThreadLocked(MergeThreadStats, stats);
87   }
88   stats->MergeFrom(&unknown_thread_stats);
89   {
90     Lock lock(&dead_threads_stats_lock);
91     stats->MergeFrom(&dead_threads_stats);
92   }
93   // This is not very accurate: we may miss allocation peaks that happen
94   // between two updates of accumulated_stats_. For more accurate bookkeeping
95   // the maximum should be updated on every malloc(), which is unacceptable.
96   if (max_malloced_memory < stats->malloced) {
97     max_malloced_memory = stats->malloced;
98   }
99 }
100 
101 void FlushToDeadThreadStats(AsanStats *stats) {
102   Lock lock(&dead_threads_stats_lock);
103   dead_threads_stats.MergeFrom(stats);
104   stats->Clear();
105 }
106 
107 void FillMallocStatistics(AsanMallocStats *malloc_stats) {
108   AsanStats stats;
109   GetAccumulatedStats(&stats);
110   malloc_stats->blocks_in_use = stats.mallocs;
111   malloc_stats->size_in_use = stats.malloced;
112   malloc_stats->max_size_in_use = max_malloced_memory;
113   malloc_stats->size_allocated = stats.mmaped;
114 }
115 
116 AsanStats &GetCurrentThreadStats() {
117   AsanThread *t = GetCurrentThread();
118   return (t) ? t->stats() : unknown_thread_stats;
119 }
120 
121 static void PrintAccumulatedStats() {
122   AsanStats stats;
123   GetAccumulatedStats(&stats);
124   // Use lock to keep reports from mixing up.
125   Lock lock(&print_lock);
126   stats.Print();
127   StackDepotStats stack_depot_stats = StackDepotGetStats();
128   Printf("Stats: StackDepot: %zd ids; %zdM allocated\n",
129          stack_depot_stats.n_uniq_ids, stack_depot_stats.allocated >> 20);
130   PrintInternalAllocatorStats();
131 }
132 
133 }  // namespace __asan
134 
135 // ---------------------- Interface ---------------- {{{1
136 using namespace __asan;
137 
138 uptr __sanitizer_get_current_allocated_bytes() {
139   AsanStats stats;
140   GetAccumulatedStats(&stats);
141   uptr malloced = stats.malloced;
142   uptr freed = stats.freed;
143   // Return sane value if malloced < freed due to racy
144   // way we update accumulated stats.
145   return (malloced > freed) ? malloced - freed : 1;
146 }
147 
148 uptr __sanitizer_get_heap_size() {
149   AsanStats stats;
150   GetAccumulatedStats(&stats);
151   return stats.mmaped - stats.munmaped;
152 }
153 
154 uptr __sanitizer_get_free_bytes() {
155   AsanStats stats;
156   GetAccumulatedStats(&stats);
157   uptr total_free = stats.mmaped
158                   - stats.munmaped
159                   + stats.really_freed;
160   uptr total_used = stats.malloced
161                   + stats.malloced_redzones;
162   // Return sane value if total_free < total_used due to racy
163   // way we update accumulated stats.
164   return (total_free > total_used) ? total_free - total_used : 1;
165 }
166 
167 uptr __sanitizer_get_unmapped_bytes() {
168   return 0;
169 }
170 
171 void __asan_print_accumulated_stats() {
172   PrintAccumulatedStats();
173 }
174