sched: default thread attributes

This makes it easier to create a thread with no special properties.

core/sched.cc

@@ -86,12 +86,12 @@ void thread::yield()
 }
 
 thread::stack_info::stack_info()
-    : begin(), size()
+    : begin(malloc(65536)), size(65536), owned(true)
 {
 }
 
 thread::stack_info::stack_info(void* _begin, size_t _size)
-    : begin(_begin), size(_size)
+    : begin(_begin), size(_size), owned(false)
 {
     auto end = align_down(begin + size, 16);
     size = static_cast<char*>(end) - static_cast<char*>(begin);

drivers/virtio-blk.cc

@@ -98,10 +98,7 @@ struct driver virtio_blk_driver = {
                       sizeof(_config.capacity));
         debug(fmt("capacity of the device is %x") % (u64)_config.capacity);
 
-        void* stk1 = malloc(10000);
-        thread::attr attr;
-        attr.stack = {stk1, 10000};
-        thread* worker = new thread([this] { this->response_worker(); } , attr);
+        thread* worker = new thread([this] { this->response_worker(); });
         worker->wake(); // just to keep gcc happy about unused var
 
         _dev->add_dev_status(VIRTIO_CONFIG_S_DRIVER_OK);

drivers/virtio-vring.cc

@@ -44,11 +44,8 @@ namespace virtio {
         _avail_count = num;
 
         msix_isr_list* isrs = new msix_isr_list;
-        void* stk1 = malloc(10000);
         _callback = nullptr;
-        thread::attr attr;
-        attr.stack = {stk1, 10000};
-        thread* isr = new thread([this] { if (_callback) _callback(); }, attr);
+        thread* isr = new thread([this] { if (_callback) _callback(); });
 
         isrs->insert(std::make_pair(_q_index, isr));
         interrupt_manager::instance()->easy_register(_dev, *isrs);

include/sched.hh

@@ -52,15 +52,19 @@ private:
 
 class thread {
 public:
-    class attr;
     struct stack_info {
         stack_info();
         stack_info(void* begin, size_t size);
         void* begin;
         size_t size;
+        bool owned; // by thread
     };
+    struct attr {
+        stack_info stack;
+    };
+
 public:
-    explicit thread(std::function<void ()> func, attr attributes,
+    explicit thread(std::function<void ()> func, attr attributes = attr(),
             bool main = false);
     ~thread();
     template <class Pred>
@@ -109,10 +113,6 @@ public:
     bi::list_member_hook<> _thread_list_link;
 };
 
-struct thread::attr {
-    stack_info stack;
-};
-
 class timer_list {
 public:
     void fired();

loader.cc

@@ -121,11 +121,8 @@ void test_threads()
     test_threads_data tt;
     tt.main = thread::current();
     tt.t1ok = tt.t2ok = true;
-    thread::attr attr1, attr2;
-    attr1.stack = { new char[10000], 10000 };
-    attr2.stack = { new char[10000], 10000 };
-    tt.t1 = new thread([&] { test_thread_1(tt); }, attr1);
-    tt.t2 = new thread([&] { test_thread_2(tt); }, attr2);
+    tt.t1 = new thread([&] { test_thread_1(tt); });
+    tt.t2 = new thread([&] { test_thread_2(tt); });
     thread::wait_until([&] { return test_ctr >= 1000; });
     tt.t1->join();
     tt.t2->join();