genode/repos/base-nova/include/base/sleep.h

/*
 * \brief  Lay back and relax
 * \author Norman Feske
 * \author Alexander Boettcher
 * \date   2010-02-01
 */

/*
 * Copyright (C) 2010-2013 Genode Labs GmbH
 *
 * This file is part of the Genode OS framework, which is distributed
 * under the terms of the GNU General Public License version 2.
 */

#ifndef _INCLUDE__BASE__SLEEP_H_
#define _INCLUDE__BASE__SLEEP_H_

/* Genode includes */
#include <base/thread.h>

/* NOVA includes */
#include <nova/syscalls.h>
#include <nova/util.h>

namespace Genode {

	__attribute__((noreturn)) inline void sleep_forever()
	{
		using namespace Nova;

		Thread_base *myself = Thread_base::myself();
		addr_t sem = myself ? myself->tid().exc_pt_sel + SM_SEL_EC : SM_SEL_EC;

		while (1) {
			if (Nova::sm_ctrl(sem, SEMAPHORE_DOWNZERO))
				nova_die();
		}
	}
}

#endif /* _INCLUDE__BASE__SLEEP_H_ */
Imported Genode release 11.11 2011-12-22 15:19:25 +00:00			`/*`
			`* \brief Lay back and relax`
			`* \author Norman Feske`
NOVA: create sm solely in core Any kernel objects are now created solely by core - namely pt, ec, sm and sc. 2012-08-01 14:16:51 +00:00			`* \author Alexander Boettcher`
Imported Genode release 11.11 2011-12-22 15:19:25 +00:00			`* \date 2010-02-01`
			`*/`

			`/*`
Update copyright headers to 2013 2013-01-10 20:44:47 +00:00			`* Copyright (C) 2010-2013 Genode Labs GmbH`
Imported Genode release 11.11 2011-12-22 15:19:25 +00:00			`*`
			`* This file is part of the Genode OS framework, which is distributed`
			`* under the terms of the GNU General Public License version 2.`
			`*/`

			`#ifndef _INCLUDE__BASE__SLEEP_H_`
			`#define _INCLUDE__BASE__SLEEP_H_`

			`/* Genode includes */`
			`#include <base/thread.h>`

			`/* NOVA includes */`
			`#include <nova/syscalls.h>`
NOVA: let thread die if SM cap is invalid Patch prevents following bugs: * In sleep_forever the thread return from semaphore down if cap is revoked during destruction of a thread. This causes an endless loop consuming time not available for other threads. * In lock_helper and cap_sel_alloc the thread return from the lock() method even if the semaphore down call failed because of an revoked semaphore. This lead to the situation that a thread subject to de-construction returns from the lock method, but not holding the lock, entering the critical section and modifying state inside the critical section. Another thread in parallel already in the critical section or entering the critical section also modifies the state. This lead to curious bugs ... * thread_nova, thread_start, irq_session Detect early bugs if the SM is gone unexpectedly where it should never happen. 2012-08-03 08:56:08 +00:00			`#include <nova/util.h>`
Imported Genode release 11.11 2011-12-22 15:19:25 +00:00
			`namespace Genode {`

			`__attribute__((noreturn)) inline void sleep_forever()`
			`{`
NOVA: create sm solely in core Any kernel objects are now created solely by core - namely pt, ec, sm and sc. 2012-08-01 14:16:51 +00:00			`using namespace Nova;`

			`Thread_base *myself = Thread_base::myself();`
NOVA: don't use externals in sleep forever Not required. 2012-08-09 12:03:24 +00:00			`addr_t sem = myself ? myself->tid().exc_pt_sel + SM_SEL_EC : SM_SEL_EC;`

NOVA: let thread die if SM cap is invalid Patch prevents following bugs: * In sleep_forever the thread return from semaphore down if cap is revoked during destruction of a thread. This causes an endless loop consuming time not available for other threads. * In lock_helper and cap_sel_alloc the thread return from the lock() method even if the semaphore down call failed because of an revoked semaphore. This lead to the situation that a thread subject to de-construction returns from the lock method, but not holding the lock, entering the critical section and modifying state inside the critical section. Another thread in parallel already in the critical section or entering the critical section also modifies the state. This lead to curious bugs ... * thread_nova, thread_start, irq_session Detect early bugs if the SM is gone unexpectedly where it should never happen. 2012-08-03 08:56:08 +00:00			`while (1) {`
			`if (Nova::sm_ctrl(sem, SEMAPHORE_DOWNZERO))`
			`nova_die();`
			`}`
Imported Genode release 11.11 2011-12-22 15:19:25 +00:00			`}`
			`}`

			`#endif /* _INCLUDE__BASE__SLEEP_H_ */`