xref: /llvm-project/compiler-rt/lib/rtsan/rtsan_context.cpp (revision e069434afcd21911ad36c55971bb8f754854c09f)
1 //===--- rtsan_context.cpp - Realtime Sanitizer -----------------*- C++ -*-===//
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 //===----------------------------------------------------------------------===//
10 
11 #include "rtsan/rtsan_context.h"
12 #include "rtsan/rtsan.h"
13 
14 #include "sanitizer_common/sanitizer_allocator_internal.h"
15 
16 #include <new>
17 #include <pthread.h>
18 
19 using namespace __sanitizer;
20 using namespace __rtsan;
21 
22 static pthread_key_t context_key;
23 static pthread_once_t key_once = PTHREAD_ONCE_INIT;
24 
25 // InternalFree cannot be passed directly to pthread_key_create
26 // because it expects a signature with only one arg
27 static void InternalFreeWrapper(void *ptr) { __sanitizer::InternalFree(ptr); }
28 
29 static __rtsan::Context &GetContextForThisThreadImpl() {
30   auto MakeThreadLocalContextKey = []() {
31     CHECK_EQ(pthread_key_create(&context_key, InternalFreeWrapper), 0);
32   };
33 
34   pthread_once(&key_once, MakeThreadLocalContextKey);
35   Context *current_thread_context =
36       static_cast<Context *>(pthread_getspecific(context_key));
37   if (current_thread_context == nullptr) {
38     current_thread_context =
39         static_cast<Context *>(InternalAlloc(sizeof(Context)));
40     new (current_thread_context) Context();
41     pthread_setspecific(context_key, current_thread_context);
42   }
43 
44   return *current_thread_context;
45 }
46 
47 __rtsan::Context::Context() = default;
48 
49 void __rtsan::Context::RealtimePush() { realtime_depth_++; }
50 
51 void __rtsan::Context::RealtimePop() { realtime_depth_--; }
52 
53 void __rtsan::Context::BypassPush() { bypass_depth_++; }
54 
55 void __rtsan::Context::BypassPop() { bypass_depth_--; }
56 
57 bool __rtsan::Context::InRealtimeContext() const { return realtime_depth_ > 0; }
58 
59 bool __rtsan::Context::IsBypassed() const { return bypass_depth_ > 0; }
60 
61 Context &__rtsan::GetContextForThisThread() {
62   return GetContextForThisThreadImpl();
63 }
64