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 #include "ffrt_async_stack.h"
16 
17 #include <cstdlib>
18 #include <mutex>
19 
20 #include <dlfcn.h>
21 
22 #include "dfx/log/ffrt_log_api.h"
23 
24 using FFRTSetStackIdFunc = void(*)(uint64_t stackId);
25 using FFRTCollectAsyncStackFunc = uint64_t(*)();
26 namespace {
27     FFRTCollectAsyncStackFunc g_collectAsyncStackFunc = nullptr;
28     FFRTSetStackIdFunc g_setStackIdFunc = nullptr;
29     void* g_asyncStackLibHandle = nullptr;
30     bool g_enabledFFRTAsyncStack = false;
31 }
32 
LoadDfxAsyncStackLib()33 static void LoadDfxAsyncStackLib()
34 {
35     const char* debuggableEnv = getenv("HAP_DEBUGGABLE");
36     if ((debuggableEnv == nullptr) || (strcmp(debuggableEnv, "true") != 0)) {
37         return;
38     }
39 
40     // if async stack is not enabled, the lib should not be unloaded
41     g_asyncStackLibHandle = dlopen("libasync_stack.z.so", RTLD_NOW);
42     if (g_asyncStackLibHandle == nullptr) {
43         return;
44     }
45 
46     g_collectAsyncStackFunc = reinterpret_cast<FFRTCollectAsyncStackFunc>(dlsym(g_asyncStackLibHandle,
47                                                                                 "CollectAsyncStack"));
48     if (g_collectAsyncStackFunc == nullptr) {
49         dlclose(g_asyncStackLibHandle);
50         g_asyncStackLibHandle = nullptr;
51         return;
52     }
53 
54     g_setStackIdFunc = reinterpret_cast<FFRTSetStackIdFunc>(dlsym(g_asyncStackLibHandle, "SetStackId"));
55     if (g_setStackIdFunc == nullptr) {
56         g_collectAsyncStackFunc = nullptr;
57         dlclose(g_asyncStackLibHandle);
58         g_asyncStackLibHandle = nullptr;
59         return;
60     }
61 
62     g_enabledFFRTAsyncStack = true;
63 }
64 
IsFFRTAsyncStackEnabled()65 static bool IsFFRTAsyncStackEnabled()
66 {
67     static std::once_flag onceFlag;
68     std::call_once(onceFlag, LoadDfxAsyncStackLib);
69     return g_enabledFFRTAsyncStack;
70 }
71 
72 namespace ffrt {
FFRTCollectAsyncStack(void)73 uint64_t FFRTCollectAsyncStack(void)
74 {
75     if (IsFFRTAsyncStackEnabled() &&
76         (g_collectAsyncStackFunc != nullptr)) {
77         return g_collectAsyncStackFunc();
78     }
79 
80     return 0;
81 }
82 
FFRTSetStackId(uint64_t stackId)83 void FFRTSetStackId(uint64_t stackId)
84 {
85     if (IsFFRTAsyncStackEnabled() &&
86         (g_setStackIdFunc != nullptr)) {
87         return g_setStackIdFunc(stackId);
88     }
89 }
90 
CloseAsyncStackLibHandle()91 void CloseAsyncStackLibHandle()
92 {
93     if (g_asyncStackLibHandle != nullptr) {
94         dlclose(g_asyncStackLibHandle);
95         g_asyncStackLibHandle = nullptr;
96     }
97 }
98 }