1 /*
2  * Copyright (c) 2024 Huawei Device Co., Ltd.
3  * Licensed under the Apache License, Version 2.0 (the "License");
4  * you may not use this file except in compliance with the License.
5  * You may obtain a copy of the License at
6  *
7  * http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software
10  * distributed under the License is distributed on an "AS IS" BASIS,
11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12  * See the License for the specific language governing permissions and
13  * limitations under the License.
14  */
15 
16 #include "async_stack.h"
17 
18 #include <pthread.h>
19 #include <threads.h>
20 #include "dfx_param.h"
21 #include "unique_stack_table.h"
22 #include "fp_unwinder.h"
23 
24 #include "dfx_log.h"
25 
26 #if defined(__aarch64__)
27 static pthread_key_t g_stackidKey;
28 static bool g_init = false;
29 
30 extern "C" void SetAsyncStackCallbackFunc(void* func) __attribute__((weak));
InitAsyncStackInner(void)31 static void InitAsyncStackInner(void)
32 {
33     if (SetAsyncStackCallbackFunc == nullptr) {
34         LOGE("%s", "failed to init async stack, could not find SetAsyncStackCallbackFunc.");
35         return;
36     }
37 
38     // init unique stack table
39     if (!OHOS::HiviewDFX::UniqueStackTable::Instance()->Init()) {
40         LOGE("%s", "failed to init unique stack table?.");
41         return;
42     }
43 
44     if (pthread_key_create(&g_stackidKey, nullptr) == 0) {
45         g_init = true;
46     } else {
47         LOGE("%s", "failed to create key for stackId.");
48         return;
49     }
50 
51     // set callback for DfxSignalHandler to read stackId
52     SetAsyncStackCallbackFunc((void*)(&GetStackId));
53 }
54 
InitAsyncStack(void)55 static bool InitAsyncStack(void)
56 {
57     static once_flag onceFlag = ONCE_FLAG_INIT;
58     call_once(&onceFlag, InitAsyncStackInner);
59     return g_init;
60 }
61 #endif
62 
CollectAsyncStack(void)63 extern "C" uint64_t CollectAsyncStack(void)
64 {
65 #if defined(__aarch64__)
66     if (!InitAsyncStack()) {
67         return 0;
68     }
69     const int32_t maxSize = 16;
70     uintptr_t pcs[maxSize] = {0};
71     int32_t skipFrameNum = 2;
72     size_t sz = static_cast<size_t>(OHOS::HiviewDFX::FpUnwinder::Unwind(pcs, maxSize, skipFrameNum));
73     uint64_t stackId = 0;
74     auto stackIdPtr = reinterpret_cast<OHOS::HiviewDFX::StackId*>(&stackId);
75     OHOS::HiviewDFX::UniqueStackTable::Instance()->PutPcsInTable(stackIdPtr, pcs, sz);
76     return stackId;
77 #else
78     return 0;
79 #endif
80 }
81 
SetStackId(uint64_t stackId)82 extern "C" void SetStackId(uint64_t stackId)
83 {
84 #if defined(__aarch64__)
85     if (!InitAsyncStack()) {
86         return;
87     }
88     pthread_setspecific(g_stackidKey, reinterpret_cast<void *>(stackId));
89 #else
90     return;
91 #endif
92 }
93 
GetStackId()94 extern "C" uint64_t GetStackId()
95 {
96 #if defined(__aarch64__)
97     if (!InitAsyncStack()) {
98         return 0;
99     }
100     return reinterpret_cast<uint64_t>(pthread_getspecific(g_stackidKey));
101 #else
102     return 0;
103 #endif
104 }