xref: /freebsd/sys/i386/include/pcpu.h (revision 1e413cf93298b5b97441a21d9a50fdcd0ee9945e)
1 /*-
2  * Copyright (c) Peter Wemm
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 #ifndef _SYS_CDEFS_H_
33 #error "sys/cdefs.h is a prerequisite for this file"
34 #endif
35 
36 #ifdef _KERNEL
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	pmap *pc_curpmap;					\
51 	struct	i386tss pc_common_tss;					\
52 	struct	segment_descriptor pc_common_tssd;			\
53 	struct	segment_descriptor *pc_tss_gdt;				\
54 	struct	segment_descriptor *pc_fsgs_gdt;			\
55 	int	pc_currentldt;						\
56 	u_int   pc_acpi_id;		/* ACPI CPU id */		\
57 	u_int	pc_apic_id;						\
58 	int	pc_private_tss		/* Flag indicating private tss */
59 
60 #ifdef lint
61 
62 extern struct pcpu *pcpup;
63 
64 #define	PCPU_GET(member)	(pcpup->pc_ ## member)
65 #define	PCPU_ADD(member, val)	(pcpu->pc_ ## member += (val))
66 #define	PCPU_INC(member)	PCPU_ADD(member, 1)
67 #define	PCPU_PTR(member)	(&pcpup->pc_ ## member)
68 #define	PCPU_SET(member, val)	(pcpup->pc_ ## member = (val))
69 
70 #elif defined(__GNUCLIKE_ASM) && defined(__GNUCLIKE___TYPEOF)
71 
72 /*
73  * Evaluates to the byte offset of the per-cpu variable name.
74  */
75 #define	__pcpu_offset(name)						\
76 	__offsetof(struct pcpu, name)
77 
78 /*
79  * Evaluates to the type of the per-cpu variable name.
80  */
81 #define	__pcpu_type(name)						\
82 	__typeof(((struct pcpu *)0)->name)
83 
84 /*
85  * Evaluates to the address of the per-cpu variable name.
86  */
87 #define	__PCPU_PTR(name) __extension__ ({				\
88 	__pcpu_type(name) *__p;						\
89 									\
90 	__asm __volatile("movl %%fs:%1,%0; addl %2,%0"			\
91 	    : "=r" (__p)						\
92 	    : "m" (*(struct pcpu *)(__pcpu_offset(pc_prvspace))),	\
93 	      "i" (__pcpu_offset(name)));				\
94 									\
95 	__p;								\
96 })
97 
98 /*
99  * Evaluates to the value of the per-cpu variable name.
100  */
101 #define	__PCPU_GET(name) __extension__ ({				\
102 	__pcpu_type(name) __res;					\
103 	struct __s {							\
104 		u_char	__b[MIN(sizeof(__pcpu_type(name)), 4)];		\
105 	} __s;								\
106 									\
107 	if (sizeof(__res) == 1 || sizeof(__res) == 2 ||			\
108 	    sizeof(__res) == 4) {					\
109 		__asm __volatile("mov %%fs:%1,%0"			\
110 		    : "=r" (__s)					\
111 		    : "m" (*(struct __s *)(__pcpu_offset(name))));	\
112 		*(struct __s *)(void *)&__res = __s;			\
113 	} else {							\
114 		__res = *__PCPU_PTR(name);				\
115 	}								\
116 	__res;								\
117 })
118 
119 /*
120  * Adds a value of the per-cpu counter name.  The implementation
121  * must be atomic with respect to interrupts.
122  */
123 #define	__PCPU_ADD(name, val) do {					\
124 	__pcpu_type(name) __val;					\
125 	struct __s {							\
126 		u_char	__b[MIN(sizeof(__pcpu_type(name)), 4)];		\
127 	} __s;								\
128 									\
129 	__val = (val);							\
130 	if (sizeof(__val) == 1 || sizeof(__val) == 2 ||			\
131 	    sizeof(__val) == 4) {					\
132 		__s = *(struct __s *)(void *)&__val;			\
133 		__asm __volatile("add %1,%%fs:%0"			\
134 		    : "=m" (*(struct __s *)(__pcpu_offset(name)))	\
135 		    : "r" (__s));					\
136 	} else								\
137 		*__PCPU_PTR(name) += __val;				\
138 } while (0)
139 
140 /*
141  * Increments the value of the per-cpu counter name.  The implementation
142  * must be atomic with respect to interrupts.
143  */
144 #define	__PCPU_INC(name) do {						\
145 	CTASSERT(sizeof(__pcpu_type(name)) == 1 ||			\
146 	    sizeof(__pcpu_type(name)) == 2 ||				\
147 	    sizeof(__pcpu_type(name)) == 4);				\
148 	if (sizeof(__pcpu_type(name)) == 1) {				\
149 		__asm __volatile("incb %%fs:%0"				\
150 		    : "=m" (*(__pcpu_type(name) *)(__pcpu_offset(name)))\
151 		    : "m" (*(__pcpu_type(name) *)(__pcpu_offset(name))));\
152 	} else if (sizeof(__pcpu_type(name)) == 2) {			\
153 		__asm __volatile("incw %%fs:%0"				\
154 		    : "=m" (*(__pcpu_type(name) *)(__pcpu_offset(name)))\
155 		    : "m" (*(__pcpu_type(name) *)(__pcpu_offset(name))));\
156 	} else if (sizeof(__pcpu_type(name)) == 4) {			\
157 		__asm __volatile("incl %%fs:%0"				\
158 		    : "=m" (*(__pcpu_type(name) *)(__pcpu_offset(name)))\
159 		    : "m" (*(__pcpu_type(name) *)(__pcpu_offset(name))));\
160 	}								\
161 } while (0)
162 
163 /*
164  * Sets the value of the per-cpu variable name to value val.
165  */
166 #define	__PCPU_SET(name, val) {						\
167 	__pcpu_type(name) __val;					\
168 	struct __s {							\
169 		u_char	__b[MIN(sizeof(__pcpu_type(name)), 4)];		\
170 	} __s;								\
171 									\
172 	__val = (val);							\
173 	if (sizeof(__val) == 1 || sizeof(__val) == 2 ||			\
174 	    sizeof(__val) == 4) {					\
175 		__s = *(struct __s *)(void *)&__val;			\
176 		__asm __volatile("mov %1,%%fs:%0"			\
177 		    : "=m" (*(struct __s *)(__pcpu_offset(name)))	\
178 		    : "r" (__s));					\
179 	} else {							\
180 		*__PCPU_PTR(name) = __val;				\
181 	}								\
182 }
183 
184 #define	PCPU_GET(member)	__PCPU_GET(pc_ ## member)
185 #define	PCPU_ADD(member, val)	__PCPU_ADD(pc_ ## member, val)
186 #define	PCPU_INC(member)	__PCPU_INC(pc_ ## member)
187 #define	PCPU_PTR(member)	__PCPU_PTR(pc_ ## member)
188 #define	PCPU_SET(member, val)	__PCPU_SET(pc_ ## member, val)
189 
190 static __inline struct thread *
191 __curthread(void)
192 {
193 	struct thread *td;
194 
195 	__asm __volatile("movl %%fs:0,%0" : "=r" (td));
196 	return (td);
197 }
198 #define	curthread		(__curthread())
199 
200 #else /* !lint || defined(__GNUCLIKE_ASM) && defined(__GNUCLIKE___TYPEOF) */
201 
202 #error "this file needs to be ported to your compiler"
203 
204 #endif /* lint, etc. */
205 
206 #endif /* _KERNEL */
207 
208 #endif /* !_MACHINE_PCPU_H_ */
209