xref: /freebsd/sys/sys/pcpu.h (revision 2b833162)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 2001 Wind River Systems, Inc.
5  * All rights reserved.
6  * Written by: John Baldwin <jhb@FreeBSD.org>
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the author nor the names of any co-contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  *
32  * $FreeBSD$
33  */
34 
35 #ifndef _SYS_PCPU_H_
36 #define	_SYS_PCPU_H_
37 
38 #ifdef LOCORE
39 #error "no assembler-serviceable parts inside"
40 #endif
41 
42 #include <sys/param.h>
43 #include <sys/_cpuset.h>
44 #include <sys/_lock.h>
45 #include <sys/_mutex.h>
46 #include <sys/_sx.h>
47 #include <sys/queue.h>
48 #include <sys/_rmlock.h>
49 #include <sys/resource.h>
50 #include <machine/pcpu.h>
51 
52 #define	DPCPU_SETNAME		"set_pcpu"
53 #define	DPCPU_SYMPREFIX		"pcpu_entry_"
54 
55 #ifdef _KERNEL
56 
57 /*
58  * Define a set for pcpu data.
59  */
60 extern uintptr_t *__start_set_pcpu;
61 __GLOBL(__start_set_pcpu);
62 extern uintptr_t *__stop_set_pcpu;
63 __GLOBL(__stop_set_pcpu);
64 
65 /*
66  * Array of dynamic pcpu base offsets.  Indexed by id.
67  */
68 extern uintptr_t dpcpu_off[];
69 
70 /*
71  * Convenience defines.
72  */
73 #define	DPCPU_START		((uintptr_t)&__start_set_pcpu)
74 #define	DPCPU_STOP		((uintptr_t)&__stop_set_pcpu)
75 #define	DPCPU_BYTES		(DPCPU_STOP - DPCPU_START)
76 #define	DPCPU_MODMIN		2048
77 #define	DPCPU_SIZE		roundup2(DPCPU_BYTES, PAGE_SIZE)
78 #define	DPCPU_MODSIZE		(DPCPU_SIZE - (DPCPU_BYTES - DPCPU_MODMIN))
79 
80 /*
81  * Declaration and definition.
82  */
83 #define	DPCPU_NAME(n)		pcpu_entry_##n
84 #define	DPCPU_DECLARE(t, n)	extern t DPCPU_NAME(n)
85 /* struct _hack is to stop this from being used with the static keyword. */
86 #define	DPCPU_DEFINE(t, n)	\
87     struct _hack; t DPCPU_NAME(n) __section(DPCPU_SETNAME) __used
88 #if defined(KLD_MODULE) && (defined(__aarch64__) || defined(__riscv) \
89 		|| defined(__powerpc64__))
90 /*
91  * On some architectures the compiler will use PC-relative load to
92  * find the address of DPCPU data with the static keyword. We then
93  * use this to find the offset of the data in a per-CPU region.
94  * This works for in the kernel as we can allocate the space ahead
95  * of time, however modules need to allocate a sepatate space and
96  * then use relocations to fix the address of the data. As
97  * PC-relative data doesn't have a relocation there is nothing for
98  * the kernel module linker to fix so data is accessed from the
99  * wrong location.
100  *
101  * This is a workaround until a better solution can be found.
102  *
103  * VNET_DEFINE_STATIC also has the same workaround.
104  */
105 #define	DPCPU_DEFINE_STATIC(t, n)	\
106     t DPCPU_NAME(n) __section(DPCPU_SETNAME) __used
107 #else
108 #define	DPCPU_DEFINE_STATIC(t, n)	\
109     static t DPCPU_NAME(n) __section(DPCPU_SETNAME) __used
110 #endif
111 
112 /*
113  * Accessors with a given base.
114  */
115 #define	_DPCPU_PTR(b, n)						\
116     (__typeof(DPCPU_NAME(n))*)((b) + (uintptr_t)&DPCPU_NAME(n))
117 #define	_DPCPU_GET(b, n)	(*_DPCPU_PTR(b, n))
118 #define	_DPCPU_SET(b, n, v)	(*_DPCPU_PTR(b, n) = v)
119 
120 /*
121  * Accessors for the current cpu.
122  */
123 #define	DPCPU_PTR(n)		_DPCPU_PTR(PCPU_GET(dynamic), n)
124 #define	DPCPU_GET(n)		(*DPCPU_PTR(n))
125 #define	DPCPU_SET(n, v)		(*DPCPU_PTR(n) = v)
126 
127 /*
128  * Accessors for remote cpus.
129  */
130 #define	DPCPU_ID_PTR(i, n)	_DPCPU_PTR(dpcpu_off[(i)], n)
131 #define	DPCPU_ID_GET(i, n)	(*DPCPU_ID_PTR(i, n))
132 #define	DPCPU_ID_SET(i, n, v)	(*DPCPU_ID_PTR(i, n) = v)
133 
134 /*
135  * Utility macros.
136  */
137 #define	DPCPU_SUM(n) __extension__					\
138 ({									\
139 	u_int _i;							\
140 	__typeof(*DPCPU_PTR(n)) sum;					\
141 									\
142 	sum = 0;							\
143 	CPU_FOREACH(_i) {						\
144 		sum += *DPCPU_ID_PTR(_i, n);				\
145 	}								\
146 	sum;								\
147 })
148 
149 #define	DPCPU_VARSUM(n, var) __extension__				\
150 ({									\
151 	u_int _i;							\
152 	__typeof((DPCPU_PTR(n))->var) sum;				\
153 									\
154 	sum = 0;							\
155 	CPU_FOREACH(_i) {						\
156 		sum += (DPCPU_ID_PTR(_i, n))->var;			\
157 	}								\
158 	sum;								\
159 })
160 
161 #define	DPCPU_ZERO(n) do {						\
162 	u_int _i;							\
163 									\
164 	CPU_FOREACH(_i) {						\
165 		bzero(DPCPU_ID_PTR(_i, n), sizeof(*DPCPU_PTR(n)));	\
166 	}								\
167 } while (0)
168 
169 #endif /* _KERNEL */
170 
171 /*
172  * This structure maps out the global data that needs to be kept on a
173  * per-cpu basis.  The members are accessed via the PCPU_GET/SET/PTR
174  * macros defined in <machine/pcpu.h>.  Machine dependent fields are
175  * defined in the PCPU_MD_FIELDS macro defined in <machine/pcpu.h>.
176  */
177 struct pcpu {
178 	struct thread	*pc_curthread;		/* Current thread */
179 	struct thread	*pc_idlethread;		/* Idle thread */
180 	struct thread	*pc_fpcurthread;	/* Fp state owner */
181 	struct thread	*pc_deadthread;		/* Zombie thread or NULL */
182 	struct pcb	*pc_curpcb;		/* Current pcb */
183 	void		*pc_sched;		/* Scheduler state */
184 	uint64_t	pc_switchtime;		/* cpu_ticks() at last csw */
185 	int		pc_switchticks;		/* `ticks' at last csw */
186 	u_int		pc_cpuid;		/* This cpu number */
187 	STAILQ_ENTRY(pcpu) pc_allcpu;
188 	struct lock_list_entry *pc_spinlocks;
189 	long		pc_cp_time[CPUSTATES];	/* statclock ticks */
190 	struct _device	*pc_device;		/* CPU device handle */
191 	void		*pc_netisr;		/* netisr SWI cookie */
192 	int8_t		pc_vfs_freevnodes;	/* freevnodes counter */
193 	char		pc_unused1[3];		/* unused pad */
194 	int		pc_domain;		/* Memory domain. */
195 	struct rm_queue	pc_rm_queue;		/* rmlock list of trackers */
196 	uintptr_t	pc_dynamic;		/* Dynamic per-cpu data area */
197 	uint64_t	pc_early_dummy_counter;	/* Startup time counter(9) */
198 	uintptr_t	pc_zpcpu_offset;	/* Offset into zpcpu allocs */
199 
200 	/*
201 	 * Keep MD fields last, so that CPU-specific variations on a
202 	 * single architecture don't result in offset variations of
203 	 * the machine-independent fields of the pcpu.  Even though
204 	 * the pcpu structure is private to the kernel, some ports
205 	 * (e.g., lsof, part of gtop) define _KERNEL and include this
206 	 * header.  While strictly speaking this is wrong, there's no
207 	 * reason not to keep the offsets of the MI fields constant
208 	 * if only to make kernel debugging easier.
209 	 */
210 	PCPU_MD_FIELDS;
211 } __aligned(CACHE_LINE_SIZE);
212 
213 #ifdef _KERNEL
214 
215 STAILQ_HEAD(cpuhead, pcpu);
216 
217 extern struct cpuhead cpuhead;
218 extern struct pcpu *cpuid_to_pcpu[];
219 
220 #define	curcpu		PCPU_GET(cpuid)
221 #define	curvidata	PCPU_GET(vidata)
222 
223 #define UMA_PCPU_ALLOC_SIZE		PAGE_SIZE
224 
225 #include <machine/pcpu_aux.h>
226 
227 #ifndef curthread
228 #define	curthread	PCPU_GET(curthread)
229 #endif
230 #define	curproc		(curthread->td_proc)
231 
232 #ifndef ZPCPU_ASSERT_PROTECTED
233 #define ZPCPU_ASSERT_PROTECTED() MPASS(curthread->td_critnest > 0)
234 #endif
235 
236 #ifndef zpcpu_offset_cpu
237 #define zpcpu_offset_cpu(cpu)	(UMA_PCPU_ALLOC_SIZE * cpu)
238 #endif
239 #ifndef zpcpu_offset
240 #define zpcpu_offset()		(PCPU_GET(zpcpu_offset))
241 #endif
242 
243 #ifndef zpcpu_base_to_offset
244 #define zpcpu_base_to_offset(base) (base)
245 #endif
246 #ifndef zpcpu_offset_to_base
247 #define zpcpu_offset_to_base(base) (base)
248 #endif
249 
250 /* Accessor to elements allocated via UMA_ZONE_PCPU zone. */
251 #define zpcpu_get(base) ({								\
252 	__typeof(base) _ptr = (void *)((char *)(base) + zpcpu_offset());		\
253 	_ptr;										\
254 })
255 
256 #define zpcpu_get_cpu(base, cpu) ({							\
257 	__typeof(base) _ptr = (void *)((char *)(base) +	zpcpu_offset_cpu(cpu));		\
258 	_ptr;										\
259 })
260 
261 /*
262  * This operation is NOT atomic and does not post any barriers.
263  * If you use this the assumption is that the target CPU will not
264  * be modifying this variable.
265  * If you need atomicity use xchg.
266  * */
267 #define zpcpu_replace(base, val) ({					\
268 	__typeof(val) *_ptr = zpcpu_get(base);				\
269 	__typeof(val) _old;						\
270 									\
271 	_old = *_ptr;							\
272 	*_ptr = val;							\
273 	_old;								\
274 })
275 
276 #define zpcpu_replace_cpu(base, val, cpu) ({				\
277 	__typeof(val) *_ptr = zpcpu_get_cpu(base, cpu);			\
278 	__typeof(val) _old;						\
279 									\
280 	_old = *_ptr;							\
281 	*_ptr = val;							\
282 	_old;								\
283 })
284 
285 #ifndef zpcpu_set_protected
286 #define zpcpu_set_protected(base, val) ({				\
287 	ZPCPU_ASSERT_PROTECTED();					\
288 	__typeof(val) *_ptr = zpcpu_get(base);				\
289 									\
290 	*_ptr = (val);							\
291 })
292 #endif
293 
294 #ifndef zpcpu_add_protected
295 #define zpcpu_add_protected(base, val) ({				\
296 	ZPCPU_ASSERT_PROTECTED();					\
297 	__typeof(val) *_ptr = zpcpu_get(base);				\
298 									\
299 	*_ptr += (val);							\
300 })
301 #endif
302 
303 #ifndef zpcpu_sub_protected
304 #define zpcpu_sub_protected(base, val) ({				\
305 	ZPCPU_ASSERT_PROTECTED();					\
306 	__typeof(val) *_ptr = zpcpu_get(base);				\
307 									\
308 	*_ptr -= (val);							\
309 })
310 #endif
311 
312 /*
313  * Machine dependent callouts.  cpu_pcpu_init() is responsible for
314  * initializing machine dependent fields of struct pcpu, and
315  * db_show_mdpcpu() is responsible for handling machine dependent
316  * fields for the DDB 'show pcpu' command.
317  */
318 void	cpu_pcpu_init(struct pcpu *pcpu, int cpuid, size_t size);
319 void	db_show_mdpcpu(struct pcpu *pcpu);
320 
321 void	*dpcpu_alloc(int size);
322 void	dpcpu_copy(void *s, int size);
323 void	dpcpu_free(void *s, int size);
324 void	dpcpu_init(void *dpcpu, int cpuid);
325 void	pcpu_destroy(struct pcpu *pcpu);
326 struct	pcpu *pcpu_find(u_int cpuid);
327 void	pcpu_init(struct pcpu *pcpu, int cpuid, size_t size);
328 
329 #endif /* _KERNEL */
330 
331 #endif /* !_SYS_PCPU_H_ */
332