rust/src/rt/rust_scheduler.cpp
2012-04-07 19:56:41 -07:00

161 lines
3.6 KiB
C++

#include "rust_globals.h"
#include "rust_scheduler.h"
#include "rust_task.h"
#include "rust_util.h"
#include "rust_sched_launcher.h"
rust_scheduler::rust_scheduler(rust_kernel *kernel,
size_t num_threads,
rust_sched_id id,
bool allow_exit,
rust_sched_launcher_factory *launchfac) :
kernel(kernel),
live_threads(num_threads),
live_tasks(0),
cur_thread(0),
may_exit(allow_exit),
num_threads(num_threads),
id(id)
{
create_task_threads(launchfac);
}
rust_scheduler::~rust_scheduler() {
destroy_task_threads();
}
rust_sched_launcher *
rust_scheduler::create_task_thread(rust_sched_launcher_factory *launchfac,
int id) {
rust_sched_launcher *thread = launchfac->create(this, id);
KLOG(kernel, kern, "created task thread: " PTR ", id: %d",
thread, id);
return thread;
}
void
rust_scheduler::destroy_task_thread(rust_sched_launcher *thread) {
KLOG(kernel, kern, "deleting task thread: " PTR, thread);
delete thread;
}
void
rust_scheduler::create_task_threads(rust_sched_launcher_factory *launchfac) {
KLOG(kernel, kern, "Using %d scheduler threads.", num_threads);
for(size_t i = 0; i < num_threads; ++i) {
threads.push(create_task_thread(launchfac, i));
}
}
void
rust_scheduler::destroy_task_threads() {
for(size_t i = 0; i < num_threads; ++i) {
destroy_task_thread(threads[i]);
}
}
void
rust_scheduler::start_task_threads()
{
for(size_t i = 0; i < num_threads; ++i) {
rust_sched_launcher *thread = threads[i];
thread->start();
}
}
void
rust_scheduler::join_task_threads()
{
for(size_t i = 0; i < num_threads; ++i) {
rust_sched_launcher *thread = threads[i];
thread->join();
}
}
void
rust_scheduler::kill_all_tasks() {
for(size_t i = 0; i < num_threads; ++i) {
rust_sched_launcher *thread = threads[i];
thread->get_loop()->kill_all_tasks();
}
}
rust_task *
rust_scheduler::create_task(rust_task *spawner, const char *name) {
size_t thread_no;
{
scoped_lock with(lock);
live_tasks++;
thread_no = cur_thread++;
if (cur_thread >= num_threads)
cur_thread = 0;
}
kernel->register_task();
rust_sched_launcher *thread = threads[thread_no];
return thread->get_loop()->create_task(spawner, name);
}
void
rust_scheduler::release_task() {
bool need_exit = false;
{
scoped_lock with(lock);
live_tasks--;
if (live_tasks == 0 && may_exit) {
need_exit = true;
}
}
kernel->unregister_task();
if (need_exit) {
exit();
}
}
void
rust_scheduler::exit() {
// Take a copy of num_threads. After the last thread exits this
// scheduler will get destroyed, and our fields will cease to exist.
size_t current_num_threads = num_threads;
for(size_t i = 0; i < current_num_threads; ++i) {
threads[i]->get_loop()->exit();
}
}
size_t
rust_scheduler::number_of_threads() {
return num_threads;
}
void
rust_scheduler::release_task_thread() {
uintptr_t new_live_threads;
{
scoped_lock with(lock);
new_live_threads = --live_threads;
}
if (new_live_threads == 0) {
kernel->release_scheduler_id(id);
}
}
void
rust_scheduler::allow_exit() {
bool need_exit = false;
{
scoped_lock with(lock);
may_exit = true;
need_exit = live_tasks == 0;
}
if (need_exit) {
exit();
}
}
void
rust_scheduler::disallow_exit() {
scoped_lock with(lock);
may_exit = false;
}