xref: /freebsd/sys/sys/pcpu.h (revision 95ee2897e98f5d444f26ed2334cc7c439f9c16c6)
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 
33 #ifndef _SYS_PCPU_H_
34 #define	_SYS_PCPU_H_
35 
36 #ifdef LOCORE
37 #error "no assembler-serviceable parts inside"
38 #endif
39 
40 #include <sys/param.h>
41 #include <sys/_cpuset.h>
42 #include <sys/_lock.h>
43 #include <sys/_mutex.h>
44 #include <sys/_sx.h>
45 #include <sys/queue.h>
46 #include <sys/_rmlock.h>
47 #include <sys/resource.h>
48 #include <machine/pcpu.h>
49 
50 #define	DPCPU_SETNAME		"set_pcpu"
51 #define	DPCPU_SYMPREFIX		"pcpu_entry_"
52 
53 #ifdef _KERNEL
54 
55 /*
56  * Define a set for pcpu data.
57  */
58 extern uintptr_t *__start_set_pcpu;
59 __GLOBL(__start_set_pcpu);
60 extern uintptr_t *__stop_set_pcpu;
61 __GLOBL(__stop_set_pcpu);
62 
63 /*
64  * Array of dynamic pcpu base offsets.  Indexed by id.
65  */
66 extern uintptr_t dpcpu_off[];
67 
68 /*
69  * Convenience defines.
70  */
71 #define	DPCPU_START		((uintptr_t)&__start_set_pcpu)
72 #define	DPCPU_STOP		((uintptr_t)&__stop_set_pcpu)
73 #define	DPCPU_BYTES		(DPCPU_STOP - DPCPU_START)
74 #define	DPCPU_MODMIN		2048
75 #define	DPCPU_SIZE		roundup2(DPCPU_BYTES, PAGE_SIZE)
76 #define	DPCPU_MODSIZE		(DPCPU_SIZE - (DPCPU_BYTES - DPCPU_MODMIN))
77 
78 /*
79  * Declaration and definition.
80  */
81 #define	DPCPU_NAME(n)		pcpu_entry_##n
82 #define	DPCPU_DECLARE(t, n)	extern t DPCPU_NAME(n)
83 /* struct _hack is to stop this from being used with the static keyword. */
84 #define	DPCPU_DEFINE(t, n)	\
85     struct _hack; t DPCPU_NAME(n) __section(DPCPU_SETNAME) __used
86 #if defined(KLD_MODULE) && (defined(__aarch64__) || defined(__riscv) \
87 		|| defined(__powerpc64__) || defined(__i386__))
88 /*
89  * On some architectures the compiler will use PC-relative load to
90  * find the address of DPCPU data with the static keyword. We then
91  * use this to find the offset of the data in a per-CPU region.
92  * This works for in the kernel as we can allocate the space ahead
93  * of time, however modules need to allocate a sepatate space and
94  * then use relocations to fix the address of the data. As
95  * PC-relative data doesn't have a relocation there is nothing for
96  * the kernel module linker to fix so data is accessed from the
97  * wrong location.
98  *
99  * This is a workaround until a better solution can be found.
100  *
101  * VNET_DEFINE_STATIC also has the same workaround.
102  */
103 #define	DPCPU_DEFINE_STATIC(t, n)	\
104     t DPCPU_NAME(n) __section(DPCPU_SETNAME) __used
105 #else
106 #define	DPCPU_DEFINE_STATIC(t, n)	\
107     static t DPCPU_NAME(n) __section(DPCPU_SETNAME) __used
108 #endif
109 
110 /*
111  * Accessors with a given base.
112  */
113 #define	_DPCPU_PTR(b, n)						\
114     (__typeof(DPCPU_NAME(n))*)((b) + (uintptr_t)&DPCPU_NAME(n))
115 #define	_DPCPU_GET(b, n)	(*_DPCPU_PTR(b, n))
116 #define	_DPCPU_SET(b, n, v)	(*_DPCPU_PTR(b, n) = v)
117 
118 /*
119  * Accessors for the current cpu.
120  */
121 #define	DPCPU_PTR(n)		_DPCPU_PTR(PCPU_GET(dynamic), n)
122 #define	DPCPU_GET(n)		(*DPCPU_PTR(n))
123 #define	DPCPU_SET(n, v)		(*DPCPU_PTR(n) = v)
124 
125 /*
126  * Accessors for remote cpus.
127  */
128 #define	DPCPU_ID_PTR(i, n)	_DPCPU_PTR(dpcpu_off[(i)], n)
129 #define	DPCPU_ID_GET(i, n)	(*DPCPU_ID_PTR(i, n))
130 #define	DPCPU_ID_SET(i, n, v)	(*DPCPU_ID_PTR(i, n) = v)
131 
132 /*
133  * Utility macros.
134  */
135 #define	DPCPU_SUM(n) __extension__					\
136 ({									\
137 	u_int _i;							\
138 	__typeof(*DPCPU_PTR(n)) sum;					\
139 									\
140 	sum = 0;							\
141 	CPU_FOREACH(_i) {						\
142 		sum += *DPCPU_ID_PTR(_i, n);				\
143 	}								\
144 	sum;								\
145 })
146 
147 #define	DPCPU_VARSUM(n, var) __extension__				\
148 ({									\
149 	u_int _i;							\
150 	__typeof((DPCPU_PTR(n))->var) sum;				\
151 									\
152 	sum = 0;							\
153 	CPU_FOREACH(_i) {						\
154 		sum += (DPCPU_ID_PTR(_i, n))->var;			\
155 	}								\
156 	sum;								\
157 })
158 
159 #define	DPCPU_ZERO(n) do {						\
160 	u_int _i;							\
161 									\
162 	CPU_FOREACH(_i) {						\
163 		bzero(DPCPU_ID_PTR(_i, n), sizeof(*DPCPU_PTR(n)));	\
164 	}								\
165 } while (0)
166 
167 #endif /* _KERNEL */
168 
169 /*
170  * This structure maps out the global data that needs to be kept on a
171  * per-cpu basis.  The members are accessed via the PCPU_GET/SET/PTR
172  * macros defined in <machine/pcpu.h>.  Machine dependent fields are
173  * defined in the PCPU_MD_FIELDS macro defined in <machine/pcpu.h>.
174  */
175 struct pcpu {
176 	struct thread	*pc_curthread;		/* Current thread */
177 	struct thread	*pc_idlethread;		/* Idle thread */
178 	struct thread	*pc_fpcurthread;	/* Fp state owner */
179 	struct thread	*pc_deadthread;		/* Zombie thread or NULL */
180 	struct pcb	*pc_curpcb;		/* Current pcb */
181 	void		*pc_sched;		/* Scheduler state */
182 	uint64_t	pc_switchtime;		/* cpu_ticks() at last csw */
183 	int		pc_switchticks;		/* `ticks' at last csw */
184 	u_int		pc_cpuid;		/* This cpu number */
185 	STAILQ_ENTRY(pcpu) pc_allcpu;
186 	struct lock_list_entry *pc_spinlocks;
187 	long		pc_cp_time[CPUSTATES];	/* statclock ticks */
188 	struct _device	*pc_device;		/* CPU device handle */
189 	void		*pc_netisr;		/* netisr SWI cookie */
190 	int8_t		pc_vfs_freevnodes;	/* freevnodes counter */
191 	char		pc_unused1[3];		/* unused pad */
192 	int		pc_domain;		/* Memory domain. */
193 	struct rm_queue	pc_rm_queue;		/* rmlock list of trackers */
194 	uintptr_t	pc_dynamic;		/* Dynamic per-cpu data area */
195 	uint64_t	pc_early_dummy_counter;	/* Startup time counter(9) */
196 	uintptr_t	pc_zpcpu_offset;	/* Offset into zpcpu allocs */
197 
198 	/*
199 	 * Keep MD fields last, so that CPU-specific variations on a
200 	 * single architecture don't result in offset variations of
201 	 * the machine-independent fields of the pcpu.  Even though
202 	 * the pcpu structure is private to the kernel, some ports
203 	 * (e.g., lsof, part of gtop) define _KERNEL and include this
204 	 * header.  While strictly speaking this is wrong, there's no
205 	 * reason not to keep the offsets of the MI fields constant
206 	 * if only to make kernel debugging easier.
207 	 */
208 	PCPU_MD_FIELDS;
209 } __aligned(CACHE_LINE_SIZE);
210 
211 #ifdef _KERNEL
212 
213 STAILQ_HEAD(cpuhead, pcpu);
214 
215 extern struct cpuhead cpuhead;
216 extern struct pcpu *cpuid_to_pcpu[];
217 
218 #define	curcpu		PCPU_GET(cpuid)
219 #define	curvidata	PCPU_GET(vidata)
220 
221 #define UMA_PCPU_ALLOC_SIZE		PAGE_SIZE
222 
223 #include <machine/pcpu_aux.h>
224 
225 #ifndef curthread
226 #define	curthread	PCPU_GET(curthread)
227 #endif
228 #define	curproc		(curthread->td_proc)
229 
230 #ifndef ZPCPU_ASSERT_PROTECTED
231 #define ZPCPU_ASSERT_PROTECTED() MPASS(curthread->td_critnest > 0)
232 #endif
233 
234 #ifndef zpcpu_offset_cpu
235 #define zpcpu_offset_cpu(cpu)	(UMA_PCPU_ALLOC_SIZE * cpu)
236 #endif
237 #ifndef zpcpu_offset
238 #define zpcpu_offset()		(PCPU_GET(zpcpu_offset))
239 #endif
240 
241 #ifndef zpcpu_base_to_offset
242 #define zpcpu_base_to_offset(base) (base)
243 #endif
244 #ifndef zpcpu_offset_to_base
245 #define zpcpu_offset_to_base(base) (base)
246 #endif
247 
248 /* Accessor to elements allocated via UMA_ZONE_PCPU zone. */
249 #define zpcpu_get(base) ({								\
250 	__typeof(base) _ptr = (void *)((char *)(base) + zpcpu_offset());		\
251 	_ptr;										\
252 })
253 
254 #define zpcpu_get_cpu(base, cpu) ({							\
255 	__typeof(base) _ptr = (void *)((char *)(base) +	zpcpu_offset_cpu(cpu));		\
256 	_ptr;										\
257 })
258 
259 /*
260  * This operation is NOT atomic and does not post any barriers.
261  * If you use this the assumption is that the target CPU will not
262  * be modifying this variable.
263  * If you need atomicity use xchg.
264  * */
265 #define zpcpu_replace(base, val) ({					\
266 	__typeof(val) *_ptr = zpcpu_get(base);				\
267 	__typeof(val) _old;						\
268 									\
269 	_old = *_ptr;							\
270 	*_ptr = val;							\
271 	_old;								\
272 })
273 
274 #define zpcpu_replace_cpu(base, val, cpu) ({				\
275 	__typeof(val) *_ptr = zpcpu_get_cpu(base, cpu);			\
276 	__typeof(val) _old;						\
277 									\
278 	_old = *_ptr;							\
279 	*_ptr = val;							\
280 	_old;								\
281 })
282 
283 #ifndef zpcpu_set_protected
284 #define zpcpu_set_protected(base, val) ({				\
285 	ZPCPU_ASSERT_PROTECTED();					\
286 	__typeof(val) *_ptr = zpcpu_get(base);				\
287 									\
288 	*_ptr = (val);							\
289 })
290 #endif
291 
292 #ifndef zpcpu_add_protected
293 #define zpcpu_add_protected(base, val) ({				\
294 	ZPCPU_ASSERT_PROTECTED();					\
295 	__typeof(val) *_ptr = zpcpu_get(base);				\
296 									\
297 	*_ptr += (val);							\
298 })
299 #endif
300 
301 #ifndef zpcpu_sub_protected
302 #define zpcpu_sub_protected(base, val) ({				\
303 	ZPCPU_ASSERT_PROTECTED();					\
304 	__typeof(val) *_ptr = zpcpu_get(base);				\
305 									\
306 	*_ptr -= (val);							\
307 })
308 #endif
309 
310 /*
311  * Machine dependent callouts.  cpu_pcpu_init() is responsible for
312  * initializing machine dependent fields of struct pcpu, and
313  * db_show_mdpcpu() is responsible for handling machine dependent
314  * fields for the DDB 'show pcpu' command.
315  */
316 void	cpu_pcpu_init(struct pcpu *pcpu, int cpuid, size_t size);
317 void	db_show_mdpcpu(struct pcpu *pcpu);
318 
319 void	*dpcpu_alloc(int size);
320 void	dpcpu_copy(void *s, int size);
321 void	dpcpu_free(void *s, int size);
322 void	dpcpu_init(void *dpcpu, int cpuid);
323 void	pcpu_destroy(struct pcpu *pcpu);
324 struct	pcpu *pcpu_find(u_int cpuid);
325 void	pcpu_init(struct pcpu *pcpu, int cpuid, size_t size);
326 
327 #endif /* _KERNEL */
328 
329 #endif /* !_SYS_PCPU_H_ */
330