xref: /freebsd/sys/i386/include/pcpu.h (revision f4b37ed0f8b307b1f3f0f630ca725d68f1dff30d)
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 #include <machine/segments.h>
37 #include <machine/tss.h>
38 
39 /*
40  * The SMP parts are setup in pmap.c and locore.s for the BSP, and
41  * mp_machdep.c sets up the data for the AP's to "see" when they awake.
42  * The reason for doing it via a struct is so that an array of pointers
43  * to each CPU's data can be set up for things like "check curproc on all
44  * other processors"
45  */
46 
47 #define	PCPU_MD_FIELDS							\
48 	char	pc_monitorbuf[128] __aligned(128); /* cache line */	\
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 	u_int	pc_cmci_mask;		/* MCx banks for CMCI */	\
60 	u_int	pc_vcpu_id;		/* Xen vCPU ID */		\
61 	char	__pad[233]
62 
63 #ifdef _KERNEL
64 
65 #ifdef lint
66 
67 extern struct pcpu *pcpup;
68 
69 #define	PCPU_GET(member)	(pcpup->pc_ ## member)
70 #define	PCPU_ADD(member, val)	(pcpup->pc_ ## member += (val))
71 #define	PCPU_INC(member)	PCPU_ADD(member, 1)
72 #define	PCPU_PTR(member)	(&pcpup->pc_ ## member)
73 #define	PCPU_SET(member, val)	(pcpup->pc_ ## member = (val))
74 
75 #elif defined(__GNUCLIKE_ASM) && defined(__GNUCLIKE___TYPEOF)
76 
77 /*
78  * Evaluates to the byte offset of the per-cpu variable name.
79  */
80 #define	__pcpu_offset(name)						\
81 	__offsetof(struct pcpu, name)
82 
83 /*
84  * Evaluates to the type of the per-cpu variable name.
85  */
86 #define	__pcpu_type(name)						\
87 	__typeof(((struct pcpu *)0)->name)
88 
89 /*
90  * Evaluates to the address of the per-cpu variable name.
91  */
92 #define	__PCPU_PTR(name) __extension__ ({				\
93 	__pcpu_type(name) *__p;						\
94 									\
95 	__asm __volatile("movl %%fs:%1,%0; addl %2,%0"			\
96 	    : "=r" (__p)						\
97 	    : "m" (*(struct pcpu *)(__pcpu_offset(pc_prvspace))),	\
98 	      "i" (__pcpu_offset(name)));				\
99 									\
100 	__p;								\
101 })
102 
103 /*
104  * Evaluates to the value of the per-cpu variable name.
105  */
106 #define	__PCPU_GET(name) __extension__ ({				\
107 	__pcpu_type(name) __res;					\
108 	struct __s {							\
109 		u_char	__b[MIN(sizeof(__res), 4)];			\
110 	} __s;								\
111 									\
112 	if (sizeof(__res) == 1 || sizeof(__res) == 2 ||			\
113 	    sizeof(__res) == 4) {					\
114 		__asm __volatile("mov %%fs:%1,%0"			\
115 		    : "=r" (__s)					\
116 		    : "m" (*(struct __s *)(__pcpu_offset(name))));	\
117 		*(struct __s *)(void *)&__res = __s;			\
118 	} else {							\
119 		__res = *__PCPU_PTR(name);				\
120 	}								\
121 	__res;								\
122 })
123 
124 /*
125  * Adds a value of the per-cpu counter name.  The implementation
126  * must be atomic with respect to interrupts.
127  */
128 #define	__PCPU_ADD(name, val) do {					\
129 	__pcpu_type(name) __val;					\
130 	struct __s {							\
131 		u_char	__b[MIN(sizeof(__val), 4)];			\
132 	} __s;								\
133 									\
134 	__val = (val);							\
135 	if (sizeof(__val) == 1 || sizeof(__val) == 2 ||			\
136 	    sizeof(__val) == 4) {					\
137 		__s = *(struct __s *)(void *)&__val;			\
138 		__asm __volatile("add %1,%%fs:%0"			\
139 		    : "=m" (*(struct __s *)(__pcpu_offset(name)))	\
140 		    : "r" (__s));					\
141 	} else								\
142 		*__PCPU_PTR(name) += __val;				\
143 } while (0)
144 
145 /*
146  * Increments the value of the per-cpu counter name.  The implementation
147  * must be atomic with respect to interrupts.
148  */
149 #define	__PCPU_INC(name) do {						\
150 	CTASSERT(sizeof(__pcpu_type(name)) == 1 ||			\
151 	    sizeof(__pcpu_type(name)) == 2 ||				\
152 	    sizeof(__pcpu_type(name)) == 4);				\
153 	if (sizeof(__pcpu_type(name)) == 1) {				\
154 		__asm __volatile("incb %%fs:%0"				\
155 		    : "=m" (*(__pcpu_type(name) *)(__pcpu_offset(name)))\
156 		    : "m" (*(__pcpu_type(name) *)(__pcpu_offset(name))));\
157 	} else if (sizeof(__pcpu_type(name)) == 2) {			\
158 		__asm __volatile("incw %%fs:%0"				\
159 		    : "=m" (*(__pcpu_type(name) *)(__pcpu_offset(name)))\
160 		    : "m" (*(__pcpu_type(name) *)(__pcpu_offset(name))));\
161 	} else if (sizeof(__pcpu_type(name)) == 4) {			\
162 		__asm __volatile("incl %%fs:%0"				\
163 		    : "=m" (*(__pcpu_type(name) *)(__pcpu_offset(name)))\
164 		    : "m" (*(__pcpu_type(name) *)(__pcpu_offset(name))));\
165 	}								\
166 } while (0)
167 
168 /*
169  * Sets the value of the per-cpu variable name to value val.
170  */
171 #define	__PCPU_SET(name, val) do {					\
172 	__pcpu_type(name) __val;					\
173 	struct __s {							\
174 		u_char	__b[MIN(sizeof(__val), 4)];			\
175 	} __s;								\
176 									\
177 	__val = (val);							\
178 	if (sizeof(__val) == 1 || sizeof(__val) == 2 ||			\
179 	    sizeof(__val) == 4) {					\
180 		__s = *(struct __s *)(void *)&__val;			\
181 		__asm __volatile("mov %1,%%fs:%0"			\
182 		    : "=m" (*(struct __s *)(__pcpu_offset(name)))	\
183 		    : "r" (__s));					\
184 	} else {							\
185 		*__PCPU_PTR(name) = __val;				\
186 	}								\
187 } while (0)
188 
189 #define	PCPU_GET(member)	__PCPU_GET(pc_ ## member)
190 #define	PCPU_ADD(member, val)	__PCPU_ADD(pc_ ## member, val)
191 #define	PCPU_INC(member)	__PCPU_INC(pc_ ## member)
192 #define	PCPU_PTR(member)	__PCPU_PTR(pc_ ## member)
193 #define	PCPU_SET(member, val)	__PCPU_SET(pc_ ## member, val)
194 
195 #define	OFFSETOF_CURTHREAD	0
196 #ifdef __clang__
197 #pragma clang diagnostic push
198 #pragma clang diagnostic ignored "-Wnull-dereference"
199 #endif
200 static __inline __pure2 struct thread *
201 __curthread(void)
202 {
203 	struct thread *td;
204 
205 	__asm("movl %%fs:%1,%0" : "=r" (td)
206 	    : "m" (*(char *)OFFSETOF_CURTHREAD));
207 	return (td);
208 }
209 #ifdef __clang__
210 #pragma clang diagnostic pop
211 #endif
212 #define	curthread		(__curthread())
213 
214 #define	OFFSETOF_CURPCB		16
215 static __inline __pure2 struct pcb *
216 __curpcb(void)
217 {
218 	struct pcb *pcb;
219 
220 	__asm("movl %%fs:%1,%0" : "=r" (pcb) : "m" (*(char *)OFFSETOF_CURPCB));
221 	return (pcb);
222 }
223 #define	curpcb		(__curpcb())
224 
225 #else /* !lint || defined(__GNUCLIKE_ASM) && defined(__GNUCLIKE___TYPEOF) */
226 
227 #error "this file needs to be ported to your compiler"
228 
229 #endif /* lint, etc. */
230 
231 #endif /* _KERNEL */
232 
233 #endif /* !_MACHINE_PCPU_H_ */
234