You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
52 lines
984 B
52 lines
984 B
---
|
|
应用是怎么启用 binder 机制的？
|
|
---
|
|
|
|
1. 了解 binder 是用来干嘛的？
|
|
2. 应用里面哪些地方用到了 binder 机制？
|
|
3. 应用的大致启动流程是怎样的？
|
|
4. 一个进程是怎么启用 binder 机制的？
|
|
|
|
#### 什么时候支持 binder 机制的？
|
|
|
|
#### binder 启动时机
|
|
|
|
```java
|
|
// handleChildProc(...)
|
|
static void zygoteInit() {
|
|
commonInit();
|
|
nativeZygoteInit();
|
|
applicationInit(...);
|
|
}
|
|
```
|
|
|
|
```c
|
|
void nativeZygoteInit(...) {
|
|
gCurRuntime->onZygoteInit();
|
|
}
|
|
```
|
|
|
|
```c
|
|
virtual void onZygoteInit() {
|
|
sp<ProcessState> proc = ProcessState::self();
|
|
proc->startThreadPool();
|
|
}
|
|
```
|
|
|
|
```c
|
|
ProcessState::ProcessState()
|
|
// open_driver() 打开 "/dev/binder" 驱动
|
|
:mDriverFD(open_driver()), ... {
|
|
if(mDriverFD>=0) {
|
|
mVMStart = mmap(0, BINDER_VM_SIZE, PROT_READ, ..., mDriverFD, 0);
|
|
}
|
|
}
|
|
```
|
|
|
|
#### 怎么启用 Binder 机制？
|
|
|
|
1. 打开 binder 驱动
|
|
2. 映射内存，分配缓冲区
|
|
3. 注册 binder 线程
|
|
4. 进入 binder loop
|
|
|
|
|