rt: Extract rust_sched_launcher from rust_task_thread

rust_sched_launcher is actually responsible for setting up the thread and
starting the loop. There will be other implementations that do not actually
set up a new thread, in order to support scheduling tasks on the main OS
thread.

mk/rt.mk

@@ -51,6 +51,7 @@ RUNTIME_CS_$(1) := \
               rt/rust_run_program.cpp \
               rt/rust_env.cpp \
               rt/rust_task_thread.cpp \
+              rt/rust_sched_launcher.cpp \
               rt/rust_scheduler.cpp \
               rt/rust_task.cpp \
               rt/rust_stack.cpp \

src/rt/rust_sched_launcher.cpp

@@ -0,0 +1,16 @@
+#include "rust_sched_launcher.h"
+#include "rust_scheduler.h"
+
+const size_t SCHED_STACK_SIZE = 1024*100;
+
+rust_sched_launcher::rust_sched_launcher(rust_scheduler *sched,
+                                         rust_srv *srv, int id)
+    : rust_thread(SCHED_STACK_SIZE),
+      kernel(sched->kernel),
+      thread(sched, srv, id) {
+}
+
+void
+rust_sched_launcher::run() {
+    thread.start_main_loop();
+}

src/rt/rust_sched_launcher.h

@@ -0,0 +1,29 @@
+#ifndef RUST_SCHED_LAUNCHER_H
+#define RUST_SCHED_LAUNCHER_H
+
+#include "rust_internal.h"
+#include "sync/rust_thread.h"
+
+#ifndef _WIN32
+#include <pthread.h>
+#else
+#include <windows.h>
+#endif
+
+class rust_sched_launcher
+  : public kernel_owned<rust_sched_launcher>,
+    public rust_thread {
+public:
+    rust_kernel *kernel;
+
+private:
+    rust_task_thread thread;
+
+public:
+    rust_sched_launcher(rust_scheduler *sched, rust_srv *srv, int id);
+
+    virtual void run();
+    rust_task_thread *get_loop() { return &thread; }
+};
+
+#endif // RUST_SCHED_LAUNCHER_H

src/rt/rust_scheduler.cpp

@@ -1,5 +1,6 @@
 #include "rust_scheduler.h"
 #include "rust_util.h"
+#include "rust_sched_launcher.h"
 
 rust_scheduler::rust_scheduler(rust_kernel *kernel,
 			       rust_srv *srv,
@@ -21,21 +22,20 @@ rust_scheduler::~rust_scheduler() {
     destroy_task_threads();
 }
 
-rust_task_thread *
+rust_sched_launcher *
 rust_scheduler::create_task_thread(int id) {
     rust_srv *srv = this->srv->clone();
-    rust_task_thread *thread =
-        new (kernel, "rust_task_thread") rust_task_thread(this, srv, id);
-    KLOG(kernel, kern, "created task thread: " PTR ", id: %d, index: %d",
-          thread, id, thread->list_index);
+    rust_sched_launcher *thread =
+        new (kernel, "rust_sched_launcher") rust_sched_launcher(this, srv, id);
+    KLOG(kernel, kern, "created task thread: " PTR ", id: %d",
+          thread, id);
     return thread;
 }
 
 void
-rust_scheduler::destroy_task_thread(rust_task_thread *thread) {
-    KLOG(kernel, kern, "deleting task thread: " PTR ", name: %s, index: %d",
-        thread, thread->name, thread->list_index);
-    rust_srv *srv = thread->srv;
+rust_scheduler::destroy_task_thread(rust_sched_launcher *thread) {
+    KLOG(kernel, kern, "deleting task thread: " PTR, thread);
+    rust_srv *srv = thread->get_loop()->srv;
     delete thread;
     delete srv;
 }
@@ -60,7 +60,7 @@ void
 rust_scheduler::start_task_threads()
 {
     for(size_t i = 0; i < num_threads; ++i) {
-        rust_task_thread *thread = threads[i];
+        rust_sched_launcher *thread = threads[i];
         thread->start();
     }
 }
@@ -69,7 +69,7 @@ void
 rust_scheduler::join_task_threads()
 {
     for(size_t i = 0; i < num_threads; ++i) {
-        rust_task_thread *thread = threads[i];
+        rust_sched_launcher *thread = threads[i];
         thread->join();
     }
 }
@@ -77,8 +77,8 @@ rust_scheduler::join_task_threads()
 void
 rust_scheduler::kill_all_tasks() {
     for(size_t i = 0; i < num_threads; ++i) {
-        rust_task_thread *thread = threads[i];
-        thread->kill_all_tasks();
+        rust_sched_launcher *thread = threads[i];
+        thread->get_loop()->kill_all_tasks();
     }
 }
 
@@ -92,8 +92,8 @@ rust_scheduler::create_task(rust_task *spawner, const char *name) {
         if (cur_thread >= num_threads)
             cur_thread = 0;
     }
-    rust_task_thread *thread = threads[thread_no];
-    return thread->create_task(spawner, name);
+    rust_sched_launcher *thread = threads[thread_no];
+    return thread->get_loop()->create_task(spawner, name);
 }
 
 void
@@ -118,7 +118,7 @@ rust_scheduler::exit() {
     // 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]->exit();
+        threads[i]->get_loop()->exit();
     }
 }
 

src/rt/rust_scheduler.h

@@ -3,6 +3,8 @@
 
 #include "rust_internal.h"
 
+class rust_sched_launcher;
+
 class rust_scheduler : public kernel_owned<rust_scheduler> {
     // FIXME: Make these private
 public:
@@ -17,7 +19,7 @@ private:
     // When this hits zero we'll tell the threads to exit
     uintptr_t live_tasks;
 
-    array_list<rust_task_thread *> threads;
+    array_list<rust_sched_launcher *> threads;
     const size_t num_threads;
     size_t cur_thread;
 
@@ -26,8 +28,8 @@ private:
     void create_task_threads();
     void destroy_task_threads();
 
-    rust_task_thread *create_task_thread(int id);
-    void destroy_task_thread(rust_task_thread *thread);
+    rust_sched_launcher *create_task_thread(int id);
+    void destroy_task_thread(rust_sched_launcher *thread);
 
     void exit();
 

src/rt/rust_task_thread.cpp

@@ -13,7 +13,6 @@ pthread_key_t rust_task_thread::task_key;
 DWORD rust_task_thread::task_key;
 #endif
 
-const size_t SCHED_STACK_SIZE = 1024*100;
 const size_t C_STACK_SIZE = 1024*1024;
 
 bool rust_task_thread::tls_initialized = false;
@@ -21,7 +20,6 @@ bool rust_task_thread::tls_initialized = false;
 rust_task_thread::rust_task_thread(rust_scheduler *sched,
                                    rust_srv *srv,
                                    int id) :
-    rust_thread(SCHED_STACK_SIZE),
     _log(srv, this),
     id(id),
     should_exit(false),
@@ -256,6 +254,8 @@ rust_task_thread::start_main_loop() {
         destroy_stack(kernel->region(), cached_c_stack);
         cached_c_stack = NULL;
     }
+
+    sched->release_task_thread();
 }
 
 rust_task *
@@ -327,11 +327,6 @@ rust_task_thread::transition(rust_task *task,
     lock.signal();
 }
 
-void rust_task_thread::run() {
-    this->start_main_loop();
-    sched->release_task_thread();
-}
-
 #ifndef _WIN32
 void
 rust_task_thread::init_tls() {

src/rt/rust_task_thread.h

@@ -2,16 +2,9 @@
 #define RUST_TASK_THREAD_H
 
 #include "rust_internal.h"
-#include "sync/rust_thread.h"
 #include "rust_stack.h"
 #include "context.h"
 
-#ifndef _WIN32
-#include <pthread.h>
-#else
-#include <windows.h>
-#endif
-
 enum rust_task_state {
     task_state_newborn,
     task_state_running,
@@ -21,8 +14,7 @@ enum rust_task_state {
 
 typedef indexed_list<rust_task> rust_task_list;
 
-struct rust_task_thread : public kernel_owned<rust_task_thread>,
-                        rust_thread
+struct rust_task_thread
 {
 private:
 
@@ -75,6 +67,7 @@ public:
 
     randctx rctx;
 
+    // FIXME: Neither of these are used
     int32_t list_index;
     const char *const name;
 
@@ -103,8 +96,6 @@ public:
                     rust_task_state src, rust_task_state dst,
                     rust_cond *cond, const char* cond_name);
 
-    virtual void run();
-
     void init_tls();
     void place_task_in_tls(rust_task *task);