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/9/sys/sys/smp.h 235796 2012-05-22 17:44:01Z iwasaki $
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
34 struct 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
44 typedef 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
66 struct cpu_group *smp_topo(void);
67 struct cpu_group *smp_topo_none(void);
68 struct cpu_group *smp_topo_1level(int l1share, int l1count, int l1flags);
69 struct cpu_group *smp_topo_2level(int l2share, int l2count, int l1share,
70 int l1count, int l1flags);
71 struct cpu_group *smp_topo_find(struct cpu_group *top, int cpu);
72
73 extern void (*cpustop_restartfunc)(void);
74 extern int smp_active;
75 extern int smp_cpus;
76 extern volatile cpuset_t started_cpus;
77 extern volatile cpuset_t stopped_cpus;
78 extern cpuset_t hlt_cpus_mask;
79 extern cpuset_t logical_cpus_mask;
80 #endif /* SMP */
81
82 extern u_int mp_maxid;
83 extern int mp_maxcpus;
84 extern int mp_ncpus;
85 extern volatile int smp_started;
86
87 extern 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
108 static __inline int
cpu_first(void)109 cpu_first(void)
110 {
111 int i;
112
113 for (i = 0;; i++)
114 if (!CPU_ABSENT(i))
115 return (i);
116 }
117
118 static __inline int
cpu_next(int i)119 cpu_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_active and smp_started are 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 */
154 struct thread;
155
156 struct cpu_group *cpu_topo(void);
157 void cpu_mp_announce(void);
158 int cpu_mp_probe(void);
159 void cpu_mp_setmaxid(void);
160 void cpu_mp_start(void);
161
162 void forward_signal(struct thread *);
163 int restart_cpus(cpuset_t);
164 int stop_cpus(cpuset_t);
165 int stop_cpus_hard(cpuset_t);
166 #if defined(__amd64__) || defined(__i386__)
167 int suspend_cpus(cpuset_t);
168 #endif
169 void smp_rendezvous_action(void);
170 extern struct mtx smp_ipi_mtx;
171
172 #endif /* SMP */
173 void smp_no_rendevous_barrier(void *);
174 void smp_rendezvous(void (*)(void *),
175 void (*)(void *),
176 void (*)(void *),
177 void *arg);
178 void smp_rendezvous_cpus(cpuset_t,
179 void (*)(void *),
180 void (*)(void *),
181 void (*)(void *),
182 void *arg);
183 #endif /* !LOCORE */
184 #endif /* _KERNEL */
185 #endif /* _SYS_SMP_H_ */
186