pcpu.h revision 170291
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: head/sys/i386/include/pcpu.h 170291 2007-06-04 21:38:48Z attilio $
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
62extern 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
190static __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