xref: /llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_stackdepot.cpp (revision bf18253b0ee543f98119e5ab6a5b57d05c24d314)
1 //===-- sanitizer_stackdepot.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 shared between AddressSanitizer and ThreadSanitizer
10 // run-time libraries.
11 //===----------------------------------------------------------------------===//
12 
13 #include "sanitizer_stackdepot.h"
14 
15 #include "sanitizer_common.h"
16 #include "sanitizer_hash.h"
17 #include "sanitizer_stack_store.h"
18 #include "sanitizer_stackdepotbase.h"
19 
20 namespace __sanitizer {
21 
22 struct StackDepotNode {
23   using hash_type = u64;
24   hash_type stack_hash;
25   u32 link;
26   StackStore::Id store_id;
27 
28   static const u32 kTabSizeLog = SANITIZER_ANDROID ? 16 : 20;
29 
30   typedef StackTrace args_type;
31   bool eq(hash_type hash, const args_type &args) const {
32     return hash == stack_hash;
33   }
34   static uptr allocated();
35   static hash_type hash(const args_type &args) {
36     MurMur2Hash64Builder H(args.size * sizeof(uptr));
37     for (uptr i = 0; i < args.size; i++) H.add(args.trace[i]);
38     H.add(args.tag);
39     return H.get();
40   }
41   static bool is_valid(const args_type &args) {
42     return args.size > 0 && args.trace;
43   }
44   void store(u32 id, const args_type &args, hash_type hash);
45   args_type load(u32 id) const;
46   static StackDepotHandle get_handle(u32 id);
47 
48   typedef StackDepotHandle handle_type;
49 };
50 
51 static StackStore stackStore;
52 
53 // FIXME(dvyukov): this single reserved bit is used in TSan.
54 typedef StackDepotBase<StackDepotNode, 1, StackDepotNode::kTabSizeLog>
55     StackDepot;
56 static StackDepot theDepot;
57 // Keep mutable data out of frequently access nodes to improve caching
58 // efficiency.
59 static TwoLevelMap<atomic_uint32_t, StackDepot::kNodesSize1,
60                    StackDepot::kNodesSize2>
61     useCounts;
62 
63 int StackDepotHandle::use_count() const {
64   return atomic_load_relaxed(&useCounts[id_]);
65 }
66 
67 void StackDepotHandle::inc_use_count_unsafe() {
68   atomic_fetch_add(&useCounts[id_], 1, memory_order_relaxed);
69 }
70 
71 uptr StackDepotNode::allocated() {
72   return stackStore.Allocated() + useCounts.MemoryUsage();
73 }
74 
75 static void CompressStackStore() {
76   u64 start = MonotonicNanoTime();
77   uptr diff = stackStore.Pack(static_cast<StackStore::Compression>(
78       common_flags()->compress_stack_depot));
79   if (!diff)
80     return;
81   u64 finish = MonotonicNanoTime();
82   uptr total = stackStore.Allocated();
83   VPrintf(1, "%s: StackDepot released %zu KiB out of %zu KiB in %llu ms\n",
84           SanitizerToolName, diff >> 10, total >> 10,
85           (finish - start) / 1000000);
86 }
87 
88 void StackDepotNode::store(u32 id, const args_type &args, hash_type hash) {
89   stack_hash = hash;
90   uptr pack = 0;
91   store_id = stackStore.Store(args, &pack);
92   if (pack && common_flags()->compress_stack_depot)
93     CompressStackStore();
94 }
95 
96 StackDepotNode::args_type StackDepotNode::load(u32 id) const {
97   if (!store_id)
98     return {};
99   return stackStore.Load(store_id);
100 }
101 
102 StackDepotStats StackDepotGetStats() { return theDepot.GetStats(); }
103 
104 u32 StackDepotPut(StackTrace stack) { return theDepot.Put(stack); }
105 
106 StackDepotHandle StackDepotPut_WithHandle(StackTrace stack) {
107   return StackDepotNode::get_handle(theDepot.Put(stack));
108 }
109 
110 StackTrace StackDepotGet(u32 id) {
111   return theDepot.Get(id);
112 }
113 
114 void StackDepotLockAll() {
115   theDepot.LockAll();
116 }
117 
118 void StackDepotUnlockAll() {
119   theDepot.UnlockAll();
120 }
121 
122 void StackDepotPrintAll() {
123 #if !SANITIZER_GO
124   theDepot.PrintAll();
125 #endif
126 }
127 
128 StackDepotHandle StackDepotNode::get_handle(u32 id) {
129   return StackDepotHandle(&theDepot.nodes[id], id);
130 }
131 
132 void StackDepotTestOnlyUnmap() {
133   theDepot.TestOnlyUnmap();
134   stackStore.TestOnlyUnmap();
135 }
136 
137 } // namespace __sanitizer
138