xref: /illumos-gate/usr/src/uts/intel/asm/thread.h (revision b808966a)

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 * Copyright 2014 Nexenta Systems, Inc.  All rights reserved.
 */

#ifndef _ASM_THREAD_H
#define	_ASM_THREAD_H

#include <sys/ccompile.h>
#include <sys/types.h>

#ifdef	__cplusplus
extern "C" {
#endif

#if !defined(__lint) && defined(__GNUC__)

struct _kthread;

/*
 * 0x10 is offsetof(struct cpu, cpu_thread)
 * 0x18 is the same thing for the _LP64 version.
 * (It's also the value of CPU_THREAD in assym.h)
 * Yuck.
 */

extern __GNU_INLINE struct _kthread
*threadp(void)
{
	struct _kthread *__value;

#if defined(__amd64)
	__asm__ __volatile__(
	    "movq %%gs:0x18,%0"		/* CPU_THREAD */
	    : "=r" (__value));
#elif defined(__i386)
	__asm__ __volatile__(
	    "movl %%gs:0x10,%0"		/* CPU_THREAD */
	    : "=r" (__value));
#else
#error	"port me"
#endif
	return (__value);
}

#endif	/* !__lint && __GNUC__ */

#ifdef	__cplusplus
}
#endif

#endif	/* _ASM_THREAD_H */