smp.h revision 265606 
1/*-
2 * ----------------------------------------------------------------------------
3 * "THE BEER-WARE LICENSE" (Revision 42):
4 * <phk@FreeBSD.org> wrote this file.  As long as you retain this notice you
5 * can do whatever you want with this stuff. If we meet some day, and you think
6 * this stuff is worth it, you can buy me a beer in return.   Poul-Henning Kamp
7 * ----------------------------------------------------------------------------
8 *
9 * $FreeBSD: stable/10/sys/sys/smp.h 265606 2014-05-07 20:28:27Z scottl $
10 */
11
12#ifndef _SYS_SMP_H_
13#define _SYS_SMP_H_
14
15#ifdef _KERNEL
16
17#ifndef LOCORE
18
19#include <sys/cpuset.h>
20
21/*
22 * Topology of a NUMA or HTT system.
23 *
24 * The top level topology is an array of pointers to groups.  Each group
25 * contains a bitmask of cpus in its group or subgroups.  It may also
26 * contain a pointer to an array of child groups.
27 *
28 * The bitmasks at non leaf groups may be used by consumers who support
29 * a smaller depth than the hardware provides.
30 *
31 * The topology may be omitted by systems where all CPUs are equal.
32 */
33
34struct cpu_group {
35	struct cpu_group *cg_parent;	/* Our parent group. */
36	struct cpu_group *cg_child;	/* Optional children groups. */
37	cpuset_t	cg_mask;	/* Mask of cpus in this group. */
38	int32_t		cg_count;	/* Count of cpus in this group. */
39	int16_t		cg_children;	/* Number of children groups. */
40	int8_t		cg_level;	/* Shared cache level. */
41	int8_t		cg_flags;	/* Traversal modifiers. */
42};
43
44typedef struct cpu_group *cpu_group_t;
45
46/*
47 * Defines common resources for CPUs in the group.  The highest level
48 * resource should be used when multiple are shared.
49 */
50#define	CG_SHARE_NONE	0
51#define	CG_SHARE_L1	1
52#define	CG_SHARE_L2	2
53#define	CG_SHARE_L3	3
54
55/*
56 * Behavior modifiers for load balancing and affinity.
57 */
58#define	CG_FLAG_HTT	0x01		/* Schedule the alternate core last. */
59#define	CG_FLAG_SMT	0x02		/* New age htt, less crippled. */
60#define	CG_FLAG_THREAD	(CG_FLAG_HTT | CG_FLAG_SMT)	/* Any threading. */
61
62/*
63 * Convenience routines for building topologies.
64 */
65#ifdef SMP
66struct cpu_group *smp_topo(void);
67struct cpu_group *smp_topo_none(void);
68struct cpu_group *smp_topo_1level(int l1share, int l1count, int l1flags);
69struct cpu_group *smp_topo_2level(int l2share, int l2count, int l1share,
70    int l1count, int l1flags);
71struct cpu_group *smp_topo_find(struct cpu_group *top, int cpu);
72
73extern void (*cpustop_restartfunc)(void);
74extern int smp_cpus;
75extern volatile cpuset_t started_cpus;
76extern volatile cpuset_t stopped_cpus;
77extern volatile cpuset_t suspended_cpus;
78extern cpuset_t hlt_cpus_mask;
79extern cpuset_t logical_cpus_mask;
80#endif /* SMP */
81
82extern u_int mp_maxid;
83extern int mp_maxcpus;
84extern int mp_ncpus;
85extern volatile int smp_started;
86
87extern cpuset_t all_cpus;
88
89/*
90 * Macro allowing us to determine whether a CPU is absent at any given
91 * time, thus permitting us to configure sparse maps of cpuid-dependent
92 * (per-CPU) structures.
93 */
94#define	CPU_ABSENT(x_cpu)	(!CPU_ISSET(x_cpu, &all_cpus))
95
96/*
97 * Macros to iterate over non-absent CPUs.  CPU_FOREACH() takes an
98 * integer iterator and iterates over the available set of CPUs.
99 * CPU_FIRST() returns the id of the first non-absent CPU.  CPU_NEXT()
100 * returns the id of the next non-absent CPU.  It will wrap back to
101 * CPU_FIRST() once the end of the list is reached.  The iterators are
102 * currently implemented via inline functions.
103 */
104#define	CPU_FOREACH(i)							\
105	for ((i) = 0; (i) <= mp_maxid; (i)++)				\
106		if (!CPU_ABSENT((i)))
107
108static __inline int
109cpu_first(void)
110{
111	int i;
112
113	for (i = 0;; i++)
114		if (!CPU_ABSENT(i))
115			return (i);
116}
117
118static __inline int
119cpu_next(int i)
120{
121
122	for (;;) {
123		i++;
124		if (i > mp_maxid)
125			i = 0;
126		if (!CPU_ABSENT(i))
127			return (i);
128	}
129}
130
131#define	CPU_FIRST()	cpu_first()
132#define	CPU_NEXT(i)	cpu_next((i))
133
134#ifdef SMP
135/*
136 * Machine dependent functions used to initialize MP support.
137 *
138 * The cpu_mp_probe() should check to see if MP support is present and return
139 * zero if it is not or non-zero if it is.  If MP support is present, then
140 * cpu_mp_start() will be called so that MP can be enabled.  This function
141 * should do things such as startup secondary processors.  It should also
142 * setup mp_ncpus, all_cpus, and smp_cpus.  It should also ensure that
143 * smp_started is initialized at the appropriate time.
144 * Once cpu_mp_start() returns, machine independent MP startup code will be
145 * executed and a simple message will be output to the console.  Finally,
146 * cpu_mp_announce() will be called so that machine dependent messages about
147 * the MP support may be output to the console if desired.
148 *
149 * The cpu_setmaxid() function is called very early during the boot process
150 * so that the MD code may set mp_maxid to provide an upper bound on CPU IDs
151 * that other subsystems may use.  If a platform is not able to determine
152 * the exact maximum ID that early, then it may set mp_maxid to MAXCPU - 1.
153 */
154struct thread;
155
156struct cpu_group *cpu_topo(void);
157void	cpu_mp_announce(void);
158int	cpu_mp_probe(void);
159void	cpu_mp_setmaxid(void);
160void	cpu_mp_start(void);
161
162void	forward_signal(struct thread *);
163int	restart_cpus(cpuset_t);
164int	stop_cpus(cpuset_t);
165int	stop_cpus_hard(cpuset_t);
166#if defined(__amd64__) || defined(__i386__)
167int	suspend_cpus(cpuset_t);
168int	resume_cpus(cpuset_t);
169#endif
170
171void	smp_rendezvous_action(void);
172extern	struct mtx smp_ipi_mtx;
173
174#endif /* SMP */
175
176int	quiesce_all_cpus(const char *, int);
177int	quiesce_cpus(cpuset_t, const char *, int);
178void	smp_no_rendevous_barrier(void *);
179void	smp_rendezvous(void (*)(void *),
180		       void (*)(void *),
181		       void (*)(void *),
182		       void *arg);
183void	smp_rendezvous_cpus(cpuset_t,
184		       void (*)(void *),
185		       void (*)(void *),
186		       void (*)(void *),
187		       void *arg);
188#endif /* !LOCORE */
189#endif /* _KERNEL */
190#endif /* _SYS_SMP_H_ */
191