1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  * Copyright 2014 Nexenta Systems, Inc.  All rights reserved.
  26  */
  27 
  28 #ifndef _ASM_THREAD_H
  29 #define _ASM_THREAD_H
  30 
  31 #include <sys/ccompile.h>
  32 #include <sys/types.h>
  33 
  34 #ifdef  __cplusplus
  35 extern "C" {
  36 #endif
  37 
  38 #if !defined(__lint) && defined(__GNUC__)
  39 
  40 struct _kthread;
  41 
  42 /*
  43  * 0x10 is offsetof(struct cpu, cpu_thread)
  44  * 0x18 is the same thing for the _LP64 version.
  45  * (It's also the value of CPU_THREAD in assym.h)
  46  * Yuck.
  47  */
  48 
  49 extern __GNU_INLINE struct _kthread
  50 *threadp(void)
  51 {
  52         struct _kthread *__value;
  53 
  54 #if defined(__amd64)
  55         __asm__ __volatile__(
  56             "movq %%gs:0x18,%0"         /* CPU_THREAD */
  57             : "=r" (__value));
  58 #elif defined(__i386)
  59         __asm__ __volatile__(
  60             "movl %%gs:0x10,%0"         /* CPU_THREAD */
  61             : "=r" (__value));
  62 #else
  63 #error  "port me"
  64 #endif
  65         return (__value);
  66 }
  67 
  68 #endif  /* !__lint && __GNUC__ */
  69 
  70 #ifdef  __cplusplus
  71 }
  72 #endif
  73 
  74 #endif  /* _ASM_THREAD_H */