text: /*-
   * Copyright (c) Peter Wemm <peter@netplex.com.au>
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   *
   * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   *
   * $FreeBSD: src/sys/i386/include/pcpu.h,v 1.35 2002/10/01 14:01:58 phk Exp $
   */
  
  #ifndef _MACHINE_PCPU_H_
  #define _MACHINE_PCPU_H_
  
  #ifdef _KERNEL
  
  #include <machine/segments.h>
  #include <machine/tss.h>
  
  /*
   * The SMP parts are setup in pmap.c and locore.s for the BSP, and
   * mp_machdep.c sets up the data for the AP's to "see" when they awake.
   * The reason for doing it via a struct is so that an array of pointers
   * to each CPU's data can be set up for things like "check curproc on all
   * other processors"
   */
  #define	PCPU_MD_FIELDS							\
  	struct	pcpu *pc_prvspace;		/* Self-reference */	\
  	struct	i386tss pc_common_tss;					\
  	struct	segment_descriptor pc_common_tssd;			\
  	struct	segment_descriptor *pc_tss_gdt;				\
  	int	pc_currentldt;						\
  	u_int32_t pc_int_pending;	/* master int pending flag */   \
  	u_int32_t pc_ipending;	/* pending slow interrupts */		\
  	u_int32_t pc_fpending;	/* pending fast interrupts */		\
  	u_int32_t pc_spending 	/* pending soft interrupts */
  
  #if defined(lint)
   
  extern struct pcpu *pcpup;
   
  #define PCPU_GET(member)        (pcpup->pc_ ## member)
  #define PCPU_PTR(member)        (&pcpup->pc_ ## member)
  #define PCPU_SET(member,value)  (pcpup->pc_ ## member = (value))
   
  #elif defined(__GNUC__)
  
  /*
   * Evaluates to the byte offset of the per-cpu variable name.
   */
  #define	__pcpu_offset(name)						\
  	__offsetof(struct pcpu, name)
  
  /*
   * Evaluates to the type of the per-cpu variable name.
   */
  #define	__pcpu_type(name)						\
  	__typeof(((struct pcpu *)0)->name)
  
  /*
   * Evaluates to the address of the per-cpu variable name.
   */
  #define	__PCPU_PTR(name) ({						\
  	__pcpu_type(name) *__p;						\
  									\
  	__asm __volatile("movl %%fs:%1,%0; addl %2,%0"			\
  	    : "=r" (__p)						\
  	    : "m" (*(struct pcpu *)(__pcpu_offset(pc_prvspace))),	\
  	      "i" (__pcpu_offset(name)));				\
  									\
  	__p;								\
  })
  
  /*
   * Evaluates to the value of the per-cpu variable name.
   */
  #define	__PCPU_GET(name) ({						\
  	__pcpu_type(name) __result;					\
  									\
  	if (sizeof(__result) == 1) {					\
  		u_char __b;						\
  		__asm __volatile("movb %%fs:%1,%0"			\
  		    : "=r" (__b)					\
  		    : "m" (*(u_char *)(__pcpu_offset(name))));		\
  		__result = *(__pcpu_type(name) *)&__b;			\
  	} else if (sizeof(__result) == 2) {				\
  		u_short __w;						\
  		__asm __volatile("movw %%fs:%1,%0"			\
  		    : "=r" (__w)					\
  		    : "m" (*(u_short *)(__pcpu_offset(name))));		\
  		__result = *(__pcpu_type(name) *)&__w;			\
  	} else if (sizeof(__result) == 4) {				\
  		u_int __i;						\
  		__asm __volatile("movl %%fs:%1,%0"			\
  		    : "=r" (__i)					\
  		    : "m" (*(u_int *)(__pcpu_offset(name))));		\
  		__result = *(__pcpu_type(name) *)&__i;			\
  	} else {							\
  		__result = *__PCPU_PTR(name);				\
  	}								\
  									\
  	__result;							\
  })
  
  /*
   * Sets the value of the per-cpu variable name to value val.
   */
  #define	__PCPU_SET(name, val) ({					\
  	__pcpu_type(name) __val = (val);				\
  									\
  	if (sizeof(__val) == 1) {					\
  		u_char __b;						\
  		__b = *(u_char *)&__val;				\
  		__asm __volatile("movb %1,%%fs:%0"			\
  		    : "=m" (*(u_char *)(__pcpu_offset(name)))		\
  		    : "r" (__b));					\
  	} else if (sizeof(__val) == 2) {				\
  		u_short __w;						\
  		__w = *(u_short *)&__val;				\
  		__asm __volatile("movw %1,%%fs:%0"			\
  		    : "=m" (*(u_short *)(__pcpu_offset(name)))		\
  		    : "r" (__w));					\
  	} else if (sizeof(__val) == 4) {				\
  		u_int __i;						\
  		__i = *(u_int *)&__val;					\
  		__asm __volatile("movl %1,%%fs:%0"			\
  		    : "=m" (*(u_int *)(__pcpu_offset(name)))		\
  		    : "r" (__i));					\
  	} else {							\
  		*__PCPU_PTR(name) = __val;				\
  	}								\
  })
  
  #define	PCPU_GET(member)	__PCPU_GET(pc_ ## member)
  #define	PCPU_PTR(member)	__PCPU_PTR(pc_ ## member)
  #define	PCPU_SET(member, val)	__PCPU_SET(pc_ ## member, val)
  
  #else
  #error gcc or lint is required to use this file
  #endif
  
  #endif	/* _KERNEL */
  
  #endif	/* ! _MACHINE_PCPU_H_ */
  