1 /*-
2 * SPDX-License-Identifier: Beerware
3 *
4 * ----------------------------------------------------------------------------
5 * "THE BEER-WARE LICENSE" (Revision 42):
6 * <phk@FreeBSD.org> wrote this file. As long as you retain this notice you
7 * can do whatever you want with this stuff. If we meet some day, and you think
8 * this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp
9 * ----------------------------------------------------------------------------
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 #include <sys/queue.h>
21
22 /*
23 * Types of nodes in the topological tree.
24 */
25 typedef enum {
26 /* No node has this type; can be used in topo API calls. */
27 TOPO_TYPE_DUMMY,
28 /* Processing unit aka computing unit aka logical CPU. */
29 TOPO_TYPE_PU,
30 /* Physical subdivision of a package. */
31 TOPO_TYPE_CORE,
32 /* CPU L1/L2/L3 cache. */
33 TOPO_TYPE_CACHE,
34 /* Package aka chip, equivalent to socket. */
35 TOPO_TYPE_PKG,
36 /* NUMA node. */
37 TOPO_TYPE_NODE,
38 /* Other logical or physical grouping of PUs. */
39 /* E.g. PUs on the same dye, or PUs sharing an FPU. */
40 TOPO_TYPE_GROUP,
41 /* The whole system. */
42 TOPO_TYPE_SYSTEM
43 } topo_node_type;
44
45 /* Hardware indenitifier of a topology component. */
46 typedef unsigned int hwid_t;
47 /* Logical CPU idenitifier. */
48 typedef int cpuid_t;
49
50 /* A node in the topology. */
51 struct topo_node {
52 struct topo_node *parent;
53 TAILQ_HEAD(topo_children, topo_node) children;
54 TAILQ_ENTRY(topo_node) siblings;
55 cpuset_t cpuset;
56 topo_node_type type;
57 uintptr_t subtype;
58 hwid_t hwid;
59 cpuid_t id;
60 int nchildren;
61 int cpu_count;
62 };
63
64 /*
65 * Scheduling topology of a NUMA or SMP system.
66 *
67 * The top level topology is an array of pointers to groups. Each group
68 * contains a bitmask of cpus in its group or subgroups. It may also
69 * contain a pointer to an array of child groups.
70 *
71 * The bitmasks at non leaf groups may be used by consumers who support
72 * a smaller depth than the hardware provides.
73 *
74 * The topology may be omitted by systems where all CPUs are equal.
75 */
76
77 struct cpu_group {
78 struct cpu_group *cg_parent; /* Our parent group. */
79 struct cpu_group *cg_child; /* Optional children groups. */
80 cpuset_t cg_mask; /* Mask of cpus in this group. */
81 int32_t cg_count; /* Count of cpus in this group. */
82 int32_t cg_first; /* First cpu in this group. */
83 int32_t cg_last; /* Last cpu in this group. */
84 int16_t cg_children; /* Number of children groups. */
85 int8_t cg_level; /* Shared cache level. */
86 int8_t cg_flags; /* Traversal modifiers. */
87 };
88
89 typedef struct cpu_group *cpu_group_t;
90
91 /*
92 * Defines common resources for CPUs in the group. The highest level
93 * resource should be used when multiple are shared.
94 */
95 #define CG_SHARE_NONE 0
96 #define CG_SHARE_L1 1
97 #define CG_SHARE_L2 2
98 #define CG_SHARE_L3 3
99
100 #define MAX_CACHE_LEVELS CG_SHARE_L3
101
102 /*
103 * Behavior modifiers for load balancing and affinity.
104 */
105 #define CG_FLAG_HTT 0x01 /* Schedule the alternate core last. */
106 #define CG_FLAG_SMT 0x02 /* New age htt, less crippled. */
107 #define CG_FLAG_THREAD (CG_FLAG_HTT | CG_FLAG_SMT) /* Any threading. */
108 #define CG_FLAG_NODE 0x04 /* NUMA node. */
109
110 /*
111 * Convenience routines for building and traversing topologies.
112 */
113 #ifdef SMP
114 void topo_init_node(struct topo_node *node);
115 void topo_init_root(struct topo_node *root);
116 struct topo_node * topo_add_node_by_hwid(struct topo_node *parent, int hwid,
117 topo_node_type type, uintptr_t subtype);
118 struct topo_node * topo_find_node_by_hwid(struct topo_node *parent, int hwid,
119 topo_node_type type, uintptr_t subtype);
120 void topo_promote_child(struct topo_node *child);
121 struct topo_node * topo_next_node(struct topo_node *top,
122 struct topo_node *node);
123 struct topo_node * topo_next_nonchild_node(struct topo_node *top,
124 struct topo_node *node);
125 void topo_set_pu_id(struct topo_node *node, cpuid_t id);
126
127 enum topo_level {
128 TOPO_LEVEL_PKG = 0,
129 /*
130 * Some systems have useful sub-package core organizations. On these,
131 * a package has one or more subgroups. Each subgroup contains one or
132 * more cache groups (cores that share a last level cache).
133 */
134 TOPO_LEVEL_GROUP,
135 TOPO_LEVEL_CACHEGROUP,
136 TOPO_LEVEL_CORE,
137 TOPO_LEVEL_THREAD,
138 TOPO_LEVEL_COUNT /* Must be last */
139 };
140 struct topo_analysis {
141 int entities[TOPO_LEVEL_COUNT];
142 };
143 int topo_analyze(struct topo_node *topo_root, int all,
144 struct topo_analysis *results);
145
146 #define TOPO_FOREACH(i, root) \
147 for (i = root; i != NULL; i = topo_next_node(root, i))
148
149 struct cpu_group *smp_topo(void);
150 struct cpu_group *smp_topo_alloc(u_int count);
151 struct cpu_group *smp_topo_none(void);
152 struct cpu_group *smp_topo_1level(int l1share, int l1count, int l1flags);
153 struct cpu_group *smp_topo_2level(int l2share, int l2count, int l1share,
154 int l1count, int l1flags);
155 struct cpu_group *smp_topo_find(struct cpu_group *top, int cpu);
156
157 extern void (*cpustop_restartfunc)(void);
158 /* The suspend/resume cpusets are x86 only, but minimize ifdefs. */
159 extern volatile cpuset_t resuming_cpus; /* woken up cpus in suspend pen */
160 extern volatile cpuset_t started_cpus; /* cpus to let out of stop pen */
161 extern volatile cpuset_t stopped_cpus; /* cpus in stop pen */
162 extern volatile cpuset_t suspended_cpus; /* cpus [near] sleeping in susp pen */
163 extern volatile cpuset_t toresume_cpus; /* cpus to let out of suspend pen */
164 extern cpuset_t hlt_cpus_mask; /* XXX 'mask' is detail in old impl */
165 extern cpuset_t logical_cpus_mask;
166 #endif /* SMP */
167
168 extern u_int mp_maxid;
169 extern int mp_maxcpus;
170 extern int mp_ncores;
171 extern int mp_ncpus;
172 extern int smp_cpus;
173 extern volatile int smp_started;
174 extern int smp_threads_per_core;
175
176 extern cpuset_t all_cpus;
177 extern cpuset_t cpuset_domain[MAXMEMDOM]; /* CPUs in each NUMA domain. */
178
179 /*
180 * Macro allowing us to determine whether a CPU is absent at any given
181 * time, thus permitting us to configure sparse maps of cpuid-dependent
182 * (per-CPU) structures.
183 */
184 #define CPU_ABSENT(x_cpu) (!CPU_ISSET(x_cpu, &all_cpus))
185
186 /*
187 * Macros to iterate over non-absent CPUs. CPU_FOREACH() takes an
188 * integer iterator and iterates over the available set of CPUs.
189 * CPU_FIRST() returns the id of the first non-absent CPU. CPU_NEXT()
190 * returns the id of the next non-absent CPU. It will wrap back to
191 * CPU_FIRST() once the end of the list is reached. The iterators are
192 * currently implemented via inline functions.
193 */
194 #define CPU_FOREACH(i) \
195 for ((i) = 0; (i) <= mp_maxid; (i)++) \
196 if (!CPU_ABSENT((i)))
197
198 static __inline int
cpu_first(void)199 cpu_first(void)
200 {
201 int i;
202
203 for (i = 0;; i++)
204 if (!CPU_ABSENT(i))
205 return (i);
206 }
207
208 static __inline int
cpu_next(int i)209 cpu_next(int i)
210 {
211
212 for (;;) {
213 i++;
214 if (i > mp_maxid)
215 i = 0;
216 if (!CPU_ABSENT(i))
217 return (i);
218 }
219 }
220
221 #define CPU_FIRST() cpu_first()
222 #define CPU_NEXT(i) cpu_next((i))
223
224 #ifdef SMP
225 /*
226 * Machine dependent functions used to initialize MP support.
227 *
228 * The cpu_mp_probe() should check to see if MP support is present and return
229 * zero if it is not or non-zero if it is. If MP support is present, then
230 * cpu_mp_start() will be called so that MP can be enabled. This function
231 * should do things such as startup secondary processors. It should also
232 * setup mp_ncpus, all_cpus, and smp_cpus. It should also ensure that
233 * smp_started is initialized at the appropriate time.
234 * Once cpu_mp_start() returns, machine independent MP startup code will be
235 * executed and a simple message will be output to the console. Finally,
236 * cpu_mp_announce() will be called so that machine dependent messages about
237 * the MP support may be output to the console if desired.
238 *
239 * The cpu_setmaxid() function is called very early during the boot process
240 * so that the MD code may set mp_maxid to provide an upper bound on CPU IDs
241 * that other subsystems may use. If a platform is not able to determine
242 * the exact maximum ID that early, then it may set mp_maxid to MAXCPU - 1.
243 */
244 struct thread;
245
246 struct cpu_group *cpu_topo(void);
247 void cpu_mp_announce(void);
248 int cpu_mp_probe(void);
249 void cpu_mp_setmaxid(void);
250 void cpu_mp_start(void);
251
252 void forward_signal(struct thread *);
253 int restart_cpus(cpuset_t);
254 int stop_cpus(cpuset_t);
255 int stop_cpus_hard(cpuset_t);
256 #if defined(__amd64__) || defined(__i386__)
257 int suspend_cpus(cpuset_t);
258 int resume_cpus(cpuset_t);
259 #endif
260
261 void smp_rendezvous_action(void);
262 extern struct mtx smp_ipi_mtx;
263
264 #endif /* SMP */
265
266 int quiesce_all_cpus(const char *, int);
267 int quiesce_cpus(cpuset_t, const char *, int);
268 void quiesce_all_critical(void);
269 void cpus_fence_seq_cst(void);
270 void smp_no_rendezvous_barrier(void *);
271 void smp_rendezvous(void (*)(void *),
272 void (*)(void *),
273 void (*)(void *),
274 void *arg);
275 void smp_rendezvous_cpus(cpuset_t,
276 void (*)(void *),
277 void (*)(void *),
278 void (*)(void *),
279 void *arg);
280
281 struct smp_rendezvous_cpus_retry_arg {
282 cpuset_t cpus;
283 };
284 void smp_rendezvous_cpus_retry(cpuset_t,
285 void (*)(void *),
286 void (*)(void *),
287 void (*)(void *),
288 void (*)(void *, int),
289 struct smp_rendezvous_cpus_retry_arg *);
290
291 void smp_rendezvous_cpus_done(struct smp_rendezvous_cpus_retry_arg *);
292
293 #endif /* !LOCORE */
294 #endif /* _KERNEL */
295 #endif /* _SYS_SMP_H_ */
296