xref: /freebsd/sys/i386/include/pcpu.h (revision ee2ea5ceafed78a5bd9810beb9e3ca927180c226)
1 /*-
2  * Copyright (c) Peter Wemm <peter@netplex.com.au>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  */
28 
29 #ifndef _MACHINE_PCPU_H_
30 #define _MACHINE_PCPU_H_
31 
32 #ifdef _KERNEL
33 
34 #ifndef	__GNUC__
35 #error	gcc is required to use this file
36 #endif
37 
38 #include <machine/segments.h>
39 #include <machine/tss.h>
40 
41 /*
42  * The SMP parts are setup in pmap.c and locore.s for the BSP, and
43  * mp_machdep.c sets up the data for the AP's to "see" when they awake.
44  * The reason for doing it via a struct is so that an array of pointers
45  * to each CPU's data can be set up for things like "check curproc on all
46  * other processors"
47  */
48 #define	PCPU_MD_FIELDS							\
49 	struct	pcpu *pc_prvspace;		/* Self-reference */	\
50 	struct	i386tss pc_common_tss;					\
51 	struct	segment_descriptor pc_common_tssd;			\
52 	struct	segment_descriptor *pc_tss_gdt;				\
53 	int	pc_currentldt;						\
54 	u_int32_t pc_int_pending;	/* master int pending flag */   \
55 	u_int32_t pc_ipending;	/* pending slow interrupts */		\
56 	u_int32_t pc_fpending;	/* pending fast interrupts */		\
57 	u_int32_t pc_spending 	/* pending soft interrupts */
58 
59 /*
60  * Evaluates to the byte offset of the per-cpu variable name.
61  */
62 #define	__pcpu_offset(name)						\
63 	__offsetof(struct pcpu, name)
64 
65 /*
66  * Evaluates to the type of the per-cpu variable name.
67  */
68 #define	__pcpu_type(name)						\
69 	__typeof(((struct pcpu *)0)->name)
70 
71 /*
72  * Evaluates to the address of the per-cpu variable name.
73  */
74 #define	__PCPU_PTR(name) ({						\
75 	__pcpu_type(name) *__p;						\
76 									\
77 	__asm __volatile("movl %%fs:%1,%0; addl %2,%0"			\
78 	    : "=r" (__p)						\
79 	    : "m" (*(struct pcpu *)(__pcpu_offset(pc_prvspace))),	\
80 	      "i" (__pcpu_offset(name)));				\
81 									\
82 	__p;								\
83 })
84 
85 /*
86  * Evaluates to the value of the per-cpu variable name.
87  */
88 #define	__PCPU_GET(name) ({						\
89 	__pcpu_type(name) __result;					\
90 									\
91 	if (sizeof(__result) == 1) {					\
92 		u_char __b;						\
93 		__asm __volatile("movb %%fs:%1,%0"			\
94 		    : "=r" (__b)					\
95 		    : "m" (*(u_char *)(__pcpu_offset(name))));		\
96 		__result = *(__pcpu_type(name) *)&__b;			\
97 	} else if (sizeof(__result) == 2) {				\
98 		u_short __w;						\
99 		__asm __volatile("movw %%fs:%1,%0"			\
100 		    : "=r" (__w)					\
101 		    : "m" (*(u_short *)(__pcpu_offset(name))));		\
102 		__result = *(__pcpu_type(name) *)&__w;			\
103 	} else if (sizeof(__result) == 4) {				\
104 		u_int __i;						\
105 		__asm __volatile("movl %%fs:%1,%0"			\
106 		    : "=r" (__i)					\
107 		    : "m" (*(u_int *)(__pcpu_offset(name))));		\
108 		__result = *(__pcpu_type(name) *)&__i;			\
109 	} else {							\
110 		__result = *__PCPU_PTR(name);				\
111 	}								\
112 									\
113 	__result;							\
114 })
115 
116 /*
117  * Sets the value of the per-cpu variable name to value val.
118  */
119 #define	__PCPU_SET(name, val) ({					\
120 	__pcpu_type(name) __val = (val);				\
121 									\
122 	if (sizeof(__val) == 1) {					\
123 		u_char __b;						\
124 		__b = *(u_char *)&__val;				\
125 		__asm __volatile("movb %1,%%fs:%0"			\
126 		    : "=m" (*(u_char *)(__pcpu_offset(name)))		\
127 		    : "r" (__b));					\
128 	} else if (sizeof(__val) == 2) {				\
129 		u_short __w;						\
130 		__w = *(u_short *)&__val;				\
131 		__asm __volatile("movw %1,%%fs:%0"			\
132 		    : "=m" (*(u_short *)(__pcpu_offset(name)))		\
133 		    : "r" (__w));					\
134 	} else if (sizeof(__val) == 4) {				\
135 		u_int __i;						\
136 		__i = *(u_int *)&__val;					\
137 		__asm __volatile("movl %1,%%fs:%0"			\
138 		    : "=m" (*(u_int *)(__pcpu_offset(name)))		\
139 		    : "r" (__i));					\
140 	} else {							\
141 		*__PCPU_PTR(name) = __val;				\
142 	}								\
143 })
144 
145 #define	PCPU_GET(member)	__PCPU_GET(pc_ ## member)
146 #define	PCPU_PTR(member)	__PCPU_PTR(pc_ ## member)
147 #define	PCPU_SET(member, val)	__PCPU_SET(pc_ ## member, val)
148 
149 #endif	/* _KERNEL */
150 
151 #endif	/* ! _MACHINE_PCPU_H_ */
152