xref: /freebsd/sys/amd64/include/pcpu.h (revision f0cfa1b168014f56c02b83e5f28412cc5f78d117)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) Peter Wemm <peter@netplex.com.au>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  * $FreeBSD$
29  */
30 
31 #ifndef _MACHINE_PCPU_H_
32 #define	_MACHINE_PCPU_H_
33 
34 #ifndef _SYS_CDEFS_H_
35 #error "sys/cdefs.h is a prerequisite for this file"
36 #endif
37 
38 /*
39  * The SMP parts are setup in pmap.c and locore.s for the BSP, and
40  * mp_machdep.c sets up the data for the AP's to "see" when they awake.
41  * The reason for doing it via a struct is so that an array of pointers
42  * to each CPU's data can be set up for things like "check curproc on all
43  * other processors"
44  */
45 #define	PCPU_MD_FIELDS							\
46 	char	pc_monitorbuf[128] __aligned(128); /* cache line */	\
47 	struct	pcpu *pc_prvspace;	/* Self-reference */		\
48 	struct	pmap *pc_curpmap;					\
49 	struct	amd64tss *pc_tssp;	/* TSS segment active on CPU */	\
50 	struct	amd64tss *pc_commontssp;/* Common TSS for the CPU */	\
51 	register_t pc_rsp0;						\
52 	register_t pc_scratch_rsp;	/* User %rsp in syscall */	\
53 	u_int	pc_apic_id;						\
54 	u_int   pc_acpi_id;		/* ACPI CPU id */		\
55 	/* Pointer to the CPU %fs descriptor */				\
56 	struct user_segment_descriptor	*pc_fs32p;			\
57 	/* Pointer to the CPU %gs descriptor */				\
58 	struct user_segment_descriptor	*pc_gs32p;			\
59 	/* Pointer to the CPU LDT descriptor */				\
60 	struct system_segment_descriptor *pc_ldt;			\
61 	/* Pointer to the CPU TSS descriptor */				\
62 	struct system_segment_descriptor *pc_tss;			\
63 	uint64_t	pc_pm_save_cnt;					\
64 	u_int	pc_cmci_mask;		/* MCx banks for CMCI */	\
65 	uint64_t pc_dbreg[16];		/* ddb debugging regs */	\
66 	int pc_dbreg_cmd;		/* ddb debugging reg cmd */	\
67 	u_int	pc_vcpu_id;		/* Xen vCPU ID */		\
68 	uint32_t pc_pcid_next;						\
69 	uint32_t pc_pcid_gen;						\
70 	uint32_t pc_smp_tlb_done;	/* TLB op acknowledgement */	\
71 	char	__pad[384]		/* be divisor of PAGE_SIZE	\
72 					   after cache alignment */
73 
74 #define	PC_DBREG_CMD_NONE	0
75 #define	PC_DBREG_CMD_LOAD	1
76 
77 #ifdef _KERNEL
78 
79 #if defined(__GNUCLIKE_ASM) && defined(__GNUCLIKE___TYPEOF)
80 
81 /*
82  * Evaluates to the byte offset of the per-cpu variable name.
83  */
84 #define	__pcpu_offset(name)						\
85 	__offsetof(struct pcpu, name)
86 
87 /*
88  * Evaluates to the type of the per-cpu variable name.
89  */
90 #define	__pcpu_type(name)						\
91 	__typeof(((struct pcpu *)0)->name)
92 
93 /*
94  * Evaluates to the address of the per-cpu variable name.
95  */
96 #define	__PCPU_PTR(name) __extension__ ({				\
97 	__pcpu_type(name) *__p;						\
98 									\
99 	__asm __volatile("movq %%gs:%1,%0; addq %2,%0"			\
100 	    : "=r" (__p)						\
101 	    : "m" (*(struct pcpu *)(__pcpu_offset(pc_prvspace))),	\
102 	      "i" (__pcpu_offset(name)));				\
103 									\
104 	__p;								\
105 })
106 
107 /*
108  * Evaluates to the value of the per-cpu variable name.
109  */
110 #define	__PCPU_GET(name) __extension__ ({				\
111 	__pcpu_type(name) __res;					\
112 	struct __s {							\
113 		u_char	__b[MIN(sizeof(__pcpu_type(name)), 8)];		\
114 	} __s;								\
115 									\
116 	if (sizeof(__res) == 1 || sizeof(__res) == 2 ||			\
117 	    sizeof(__res) == 4 || sizeof(__res) == 8) {			\
118 		__asm __volatile("mov %%gs:%1,%0"			\
119 		    : "=r" (__s)					\
120 		    : "m" (*(struct __s *)(__pcpu_offset(name))));	\
121 		*(struct __s *)(void *)&__res = __s;			\
122 	} else {							\
123 		__res = *__PCPU_PTR(name);				\
124 	}								\
125 	__res;								\
126 })
127 
128 /*
129  * Adds the value to the per-cpu counter name.  The implementation
130  * must be atomic with respect to interrupts.
131  */
132 #define	__PCPU_ADD(name, val) do {					\
133 	__pcpu_type(name) __val;					\
134 	struct __s {							\
135 		u_char	__b[MIN(sizeof(__pcpu_type(name)), 8)];		\
136 	} __s;								\
137 									\
138 	__val = (val);							\
139 	if (sizeof(__val) == 1 || sizeof(__val) == 2 ||			\
140 	    sizeof(__val) == 4 || sizeof(__val) == 8) {			\
141 		__s = *(struct __s *)(void *)&__val;			\
142 		__asm __volatile("add %1,%%gs:%0"			\
143 		    : "=m" (*(struct __s *)(__pcpu_offset(name)))	\
144 		    : "r" (__s));					\
145 	} else								\
146 		*__PCPU_PTR(name) += __val;				\
147 } while (0)
148 
149 /*
150  * Increments the value of the per-cpu counter name.  The implementation
151  * must be atomic with respect to interrupts.
152  */
153 #define	__PCPU_INC(name) do {						\
154 	CTASSERT(sizeof(__pcpu_type(name)) == 1 ||			\
155 	    sizeof(__pcpu_type(name)) == 2 ||				\
156 	    sizeof(__pcpu_type(name)) == 4 ||				\
157 	    sizeof(__pcpu_type(name)) == 8);				\
158 	if (sizeof(__pcpu_type(name)) == 1) {				\
159 		__asm __volatile("incb %%gs:%0"				\
160 		    : "=m" (*(__pcpu_type(name) *)(__pcpu_offset(name)))\
161 		    : "m" (*(__pcpu_type(name) *)(__pcpu_offset(name))));\
162 	} else if (sizeof(__pcpu_type(name)) == 2) {			\
163 		__asm __volatile("incw %%gs:%0"				\
164 		    : "=m" (*(__pcpu_type(name) *)(__pcpu_offset(name)))\
165 		    : "m" (*(__pcpu_type(name) *)(__pcpu_offset(name))));\
166 	} else if (sizeof(__pcpu_type(name)) == 4) {			\
167 		__asm __volatile("incl %%gs:%0"				\
168 		    : "=m" (*(__pcpu_type(name) *)(__pcpu_offset(name)))\
169 		    : "m" (*(__pcpu_type(name) *)(__pcpu_offset(name))));\
170 	} else if (sizeof(__pcpu_type(name)) == 8) {			\
171 		__asm __volatile("incq %%gs:%0"				\
172 		    : "=m" (*(__pcpu_type(name) *)(__pcpu_offset(name)))\
173 		    : "m" (*(__pcpu_type(name) *)(__pcpu_offset(name))));\
174 	}								\
175 } while (0)
176 
177 /*
178  * Sets the value of the per-cpu variable name to value val.
179  */
180 #define	__PCPU_SET(name, val) {						\
181 	__pcpu_type(name) __val;					\
182 	struct __s {							\
183 		u_char	__b[MIN(sizeof(__pcpu_type(name)), 8)];		\
184 	} __s;								\
185 									\
186 	__val = (val);							\
187 	if (sizeof(__val) == 1 || sizeof(__val) == 2 ||			\
188 	    sizeof(__val) == 4 || sizeof(__val) == 8) {			\
189 		__s = *(struct __s *)(void *)&__val;			\
190 		__asm __volatile("mov %1,%%gs:%0"			\
191 		    : "=m" (*(struct __s *)(__pcpu_offset(name)))	\
192 		    : "r" (__s));					\
193 	} else {							\
194 		*__PCPU_PTR(name) = __val;				\
195 	}								\
196 }
197 
198 #define	get_pcpu() __extension__ ({					\
199 	struct pcpu *__pc;						\
200 									\
201 	__asm __volatile("movq %%gs:%1,%0"				\
202 	    : "=r" (__pc)						\
203 	    : "m" (*(struct pcpu *)(__pcpu_offset(pc_prvspace))));	\
204 	__pc;								\
205 })
206 
207 #define	PCPU_GET(member)	__PCPU_GET(pc_ ## member)
208 #define	PCPU_ADD(member, val)	__PCPU_ADD(pc_ ## member, val)
209 #define	PCPU_INC(member)	__PCPU_INC(pc_ ## member)
210 #define	PCPU_PTR(member)	__PCPU_PTR(pc_ ## member)
211 #define	PCPU_SET(member, val)	__PCPU_SET(pc_ ## member, val)
212 
213 #define	OFFSETOF_CURTHREAD	0
214 #ifdef __clang__
215 #pragma clang diagnostic push
216 #pragma clang diagnostic ignored "-Wnull-dereference"
217 #endif
218 static __inline __pure2 struct thread *
219 __curthread(void)
220 {
221 	struct thread *td;
222 
223 	__asm("movq %%gs:%1,%0" : "=r" (td)
224 	    : "m" (*(char *)OFFSETOF_CURTHREAD));
225 	return (td);
226 }
227 #ifdef __clang__
228 #pragma clang diagnostic pop
229 #endif
230 #define	curthread		(__curthread())
231 
232 #define	OFFSETOF_CURPCB		32
233 static __inline __pure2 struct pcb *
234 __curpcb(void)
235 {
236 	struct pcb *pcb;
237 
238 	__asm("movq %%gs:%1,%0" : "=r" (pcb) : "m" (*(char *)OFFSETOF_CURPCB));
239 	return (pcb);
240 }
241 #define	curpcb		(__curpcb())
242 
243 #define	IS_BSP()	(PCPU_GET(cpuid) == 0)
244 
245 #else /* !__GNUCLIKE_ASM || !__GNUCLIKE___TYPEOF */
246 
247 #error "this file needs to be ported to your compiler"
248 
249 #endif /* __GNUCLIKE_ASM && __GNUCLIKE___TYPEOF */
250 
251 #endif /* _KERNEL */
252 
253 #endif /* !_MACHINE_PCPU_H_ */
254