__syncthreads()在我有意使用线程丢弃的块中使用是否安全return?
文档说明__syncthreads() 必须由块中的每个线程调用,否则它将导致死锁,但实际上我从未经历过这样的行为.
示例代码:
__global__ void kernel(float* data, size_t size) {
// Drop excess threads if user put too many in kernel call.
// After the return, there are `size` active threads.
if (threadIdx.x >= size) {
return;
}
// ... do some work ...
__syncthreads(); // Is this safe?
// For the rest of the kernel, we need to drop one excess thread
// After the return, there are `size - 1` active threads …Run Code Online (Sandbox Code Playgroud)