From c48a7aa27fd845362ceb166100734cb224ec520d Mon Sep 17 00:00:00 2001
From: Norman Feske <norman.feske@genode-labs.com>
Date: Thu, 16 May 2013 20:33:13 +0200
Subject: [PATCH] vancouver: Avoid busy startup synchronizations

---
 ports/src/vancouver/console.cc | 8 ++++++--
 ports/src/vancouver/console.h  | 1 +
 ports/src/vancouver/disk.cc    | 7 +++++--
 ports/src/vancouver/disk.h     | 1 +
 ports/src/vancouver/main.cc    | 6 ------
 5 files changed, 13 insertions(+), 10 deletions(-)

diff --git a/ports/src/vancouver/console.cc b/ports/src/vancouver/console.cc
index 9aef0e8a0..f7d9de7e7 100644
--- a/ports/src/vancouver/console.cc
+++ b/ports/src/vancouver/console.cc
@@ -34,7 +34,6 @@ extern char _binary_mono_tff_start;
 Font default_font(&_binary_mono_tff_start);
 
 extern Genode::Lock global_lock;
-extern bool console_init;
 
 using Genode::env;
 using Genode::Dataspace_client;
@@ -195,7 +194,8 @@ void Vancouver_console::entry()
 	unsigned unchanged = 0;
 	bool cmp_even = 1;
 
-	console_init = true;
+	_startup_lock.unlock();
+
 	while (1) {
 		while (!input.is_pending()) {
 
@@ -304,8 +304,12 @@ void Vancouver_console::entry()
 Vancouver_console::Vancouver_console(Motherboard &mb, Genode::size_t vm_fb_size,
                                      Genode::Dataspace_capability fb_ds)
 :
+	_startup_lock(Genode::Lock::LOCKED),
 	_vm_fb_size(vm_fb_size), _mb(mb), _fb_size(0), _pixels(0), _guest_fb(0),
 	_regs(0), _fb_ds(fb_ds)
 {
 	start();
+
+	/* shake hands with console thread */
+	_startup_lock.lock();
 }
diff --git a/ports/src/vancouver/console.h b/ports/src/vancouver/console.h
index a9e2a4363..a44259fb3 100644
--- a/ports/src/vancouver/console.h
+++ b/ports/src/vancouver/console.h
@@ -46,6 +46,7 @@ class Vancouver_console : public Thread<8192>, public StaticReceiver<Vancouver_c
 {
 	private:
 
+		Genode::Lock                 _startup_lock;
 		Motherboard                 &_mb;
 		short	                    *_pixels;
 		char 	                    *_guest_fb;
diff --git a/ports/src/vancouver/disk.cc b/ports/src/vancouver/disk.cc
index 1b254bca8..5809bd926 100644
--- a/ports/src/vancouver/disk.cc
+++ b/ports/src/vancouver/disk.cc
@@ -32,13 +32,13 @@
 static Genode::Native_utcb utcb_backup;
 
 extern Genode::Lock timeouts_lock;
-extern bool disk_init;
 
 
 Vancouver_disk::Vancouver_disk(Motherboard &mb,
                                char * backing_store_base,
                                char * backing_store_fb_base)
 :
+	_startup_lock(Genode::Lock::LOCKED),
 	_mb(mb), _backing_store_base(backing_store_base),
 	_backing_store_fb_base(backing_store_fb_base)
 {
@@ -47,6 +47,9 @@ Vancouver_disk::Vancouver_disk(Motherboard &mb,
 		_diskcon[i].blk_size = 0;
 	}
 	start();
+
+	/* shake hands with disk thread */
+	_startup_lock.lock();
 }
 
 
@@ -57,7 +60,7 @@ void Vancouver_disk::entry()
 	/* attach to disk bus */
 	_mb.bus_disk.add(this, receive_static<MessageDisk>);
 
-	disk_init = true;
+	_startup_lock.unlock();
 }
 
 
diff --git a/ports/src/vancouver/disk.h b/ports/src/vancouver/disk.h
index 348759936..5563b0d94 100644
--- a/ports/src/vancouver/disk.h
+++ b/ports/src/vancouver/disk.h
@@ -48,6 +48,7 @@ class Vancouver_disk : public Genode::Thread<8192>, public StaticReceiver<Vancou
 			Genode::size_t              blk_cnt;
 		} _diskcon[MAX_DISKS];
 
+		Genode::Lock _startup_lock;
 		Motherboard &_mb;
 		char        *_backing_store_base;
 		char        *_backing_store_fb_base;
diff --git a/ports/src/vancouver/main.cc b/ports/src/vancouver/main.cc
index 192f15b1f..5586d38f0 100644
--- a/ports/src/vancouver/main.cc
+++ b/ports/src/vancouver/main.cc
@@ -92,9 +92,6 @@ Genode::Lock *utcb_lock()
 Genode::Lock global_lock(Genode::Lock::LOCKED);
 Genode::Lock timeouts_lock(Genode::Lock::UNLOCKED);
 
-volatile bool console_init = false;
-volatile bool disk_init = false;
-
 
 /* timer service */
 using Genode::Thread;
@@ -1622,9 +1619,6 @@ int main(int argc, char **argv)
 	                     guest_memory.backing_store_local_base(),
 	                     guest_memory.backing_store_fb_local_base());
 
-	/* wait for services */
-	while (!console_init || !disk_init);
-
 	machine.setup_devices(Genode::config()->xml_node().sub_node("machine"));
 
 	Genode::printf("\n--- Booting VM ---\n");