Single Task
Contents
tf::
Run a Task with a Single Thread
You can create a task to run a kernel function just once, i.e., using one GPU thread. This is handy when you want to set up a single or a few global variables that do not need multiple threads and will be used by multiple kernels afterwards. The following example creates a single-task kernel that sets gpu_variable
to 1.
sycl::queue queue; int* gpu_variable = sycl::malloc_shared<int>(1, queue); tf::Task = taskflow.emplace_on([&] (tf::syclFlow& sf) { // create a single task to set the gpu_variable to 1 tf::syclTask set_var = sf.single_task( [gpu_variable] () { *gpu_variable = 1; } ); // create one kernel task that needs access to gpu_variable tf::syclTask kernel1 = sf.parallel_for( sycl::range<1>(N), [=] (sycl::id<1> id) { data1[id] *= gpu_variable; } ); set_par.precede(kernel1); }, queue);