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 * Copyright (c) 2009 Jeffrey Roberson <jeff@freebsd.org> 9 * All rights reserved. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. Neither the name of the author nor the names of any co-contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 /* 37 * This module provides MI support for per-cpu data. 38 * 39 * Each architecture determines the mapping of logical CPU IDs to physical 40 * CPUs. The requirements of this mapping are as follows: 41 * - Logical CPU IDs must reside in the range 0 ... MAXCPU - 1. 42 * - The mapping is not required to be dense. That is, there may be 43 * gaps in the mappings. 44 * - The platform sets the value of MAXCPU in <machine/param.h>. 45 * - It is suggested, but not required, that in the non-SMP case, the 46 * platform define MAXCPU to be 1 and define the logical ID of the 47 * sole CPU as 0. 48 */ 49 50 #include <sys/cdefs.h> 51 __FBSDID("$FreeBSD$"); 52 53 #include "opt_ddb.h" 54 55 #include <sys/param.h> 56 #include <sys/systm.h> 57 #include <sys/sysctl.h> 58 #include <sys/lock.h> 59 #include <sys/malloc.h> 60 #include <sys/pcpu.h> 61 #include <sys/proc.h> 62 #include <sys/smp.h> 63 #include <sys/sx.h> 64 #include <vm/uma.h> 65 #include <ddb/ddb.h> 66 67 static MALLOC_DEFINE(M_PCPU, "Per-cpu", "Per-cpu resource accouting."); 68 69 struct dpcpu_free { 70 uintptr_t df_start; 71 int df_len; 72 TAILQ_ENTRY(dpcpu_free) df_link; 73 }; 74 75 DPCPU_DEFINE_STATIC(char, modspace[DPCPU_MODMIN] __aligned(__alignof(void *))); 76 static TAILQ_HEAD(, dpcpu_free) dpcpu_head = TAILQ_HEAD_INITIALIZER(dpcpu_head); 77 static struct sx dpcpu_lock; 78 uintptr_t dpcpu_off[MAXCPU]; 79 struct pcpu *cpuid_to_pcpu[MAXCPU]; 80 struct cpuhead cpuhead = STAILQ_HEAD_INITIALIZER(cpuhead); 81 82 /* 83 * Initialize the MI portions of a struct pcpu. 84 */ 85 void 86 pcpu_init(struct pcpu *pcpu, int cpuid, size_t size) 87 { 88 89 bzero(pcpu, size); 90 KASSERT(cpuid >= 0 && cpuid < MAXCPU, 91 ("pcpu_init: invalid cpuid %d", cpuid)); 92 pcpu->pc_cpuid = cpuid; 93 cpuid_to_pcpu[cpuid] = pcpu; 94 STAILQ_INSERT_TAIL(&cpuhead, pcpu, pc_allcpu); 95 cpu_pcpu_init(pcpu, cpuid, size); 96 pcpu->pc_rm_queue.rmq_next = &pcpu->pc_rm_queue; 97 pcpu->pc_rm_queue.rmq_prev = &pcpu->pc_rm_queue; 98 } 99 100 void 101 dpcpu_init(void *dpcpu, int cpuid) 102 { 103 struct pcpu *pcpu; 104 105 pcpu = pcpu_find(cpuid); 106 pcpu->pc_dynamic = (uintptr_t)dpcpu - DPCPU_START; 107 108 /* 109 * Initialize defaults from our linker section. 110 */ 111 memcpy(dpcpu, (void *)DPCPU_START, DPCPU_BYTES); 112 113 /* 114 * Place it in the global pcpu offset array. 115 */ 116 dpcpu_off[cpuid] = pcpu->pc_dynamic; 117 } 118 119 static void 120 dpcpu_startup(void *dummy __unused) 121 { 122 struct dpcpu_free *df; 123 124 df = malloc(sizeof(*df), M_PCPU, M_WAITOK | M_ZERO); 125 df->df_start = (uintptr_t)&DPCPU_NAME(modspace); 126 df->df_len = DPCPU_MODMIN; 127 TAILQ_INSERT_HEAD(&dpcpu_head, df, df_link); 128 sx_init(&dpcpu_lock, "dpcpu alloc lock"); 129 } 130 SYSINIT(dpcpu, SI_SUB_KLD, SI_ORDER_FIRST, dpcpu_startup, NULL); 131 132 /* 133 * UMA_PCPU_ZONE zones, that are available for all kernel 134 * consumers. Right now 64 bit zone is used for counter(9) 135 * and int zone is used for mount point counters. 136 */ 137 138 uma_zone_t pcpu_zone_int; 139 uma_zone_t pcpu_zone_64; 140 141 static void 142 pcpu_zones_startup(void) 143 { 144 145 pcpu_zone_int = uma_zcreate("int pcpu", sizeof(int), 146 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_PCPU); 147 pcpu_zone_64 = uma_zcreate("64 pcpu", sizeof(uint64_t), 148 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_PCPU); 149 } 150 SYSINIT(pcpu_zones, SI_SUB_VM, SI_ORDER_ANY, pcpu_zones_startup, NULL); 151 152 /* 153 * First-fit extent based allocator for allocating space in the per-cpu 154 * region reserved for modules. This is only intended for use by the 155 * kernel linkers to place module linker sets. 156 */ 157 void * 158 dpcpu_alloc(int size) 159 { 160 struct dpcpu_free *df; 161 void *s; 162 163 s = NULL; 164 size = roundup2(size, sizeof(void *)); 165 sx_xlock(&dpcpu_lock); 166 TAILQ_FOREACH(df, &dpcpu_head, df_link) { 167 if (df->df_len < size) 168 continue; 169 if (df->df_len == size) { 170 s = (void *)df->df_start; 171 TAILQ_REMOVE(&dpcpu_head, df, df_link); 172 free(df, M_PCPU); 173 break; 174 } 175 s = (void *)df->df_start; 176 df->df_len -= size; 177 df->df_start = df->df_start + size; 178 break; 179 } 180 sx_xunlock(&dpcpu_lock); 181 182 return (s); 183 } 184 185 /* 186 * Free dynamic per-cpu space at module unload time. 187 */ 188 void 189 dpcpu_free(void *s, int size) 190 { 191 struct dpcpu_free *df; 192 struct dpcpu_free *dn; 193 uintptr_t start; 194 uintptr_t end; 195 196 size = roundup2(size, sizeof(void *)); 197 start = (uintptr_t)s; 198 end = start + size; 199 /* 200 * Free a region of space and merge it with as many neighbors as 201 * possible. Keeping the list sorted simplifies this operation. 202 */ 203 sx_xlock(&dpcpu_lock); 204 TAILQ_FOREACH(df, &dpcpu_head, df_link) { 205 if (df->df_start > end) 206 break; 207 /* 208 * If we expand at the end of an entry we may have to 209 * merge it with the one following it as well. 210 */ 211 if (df->df_start + df->df_len == start) { 212 df->df_len += size; 213 dn = TAILQ_NEXT(df, df_link); 214 if (df->df_start + df->df_len == dn->df_start) { 215 df->df_len += dn->df_len; 216 TAILQ_REMOVE(&dpcpu_head, dn, df_link); 217 free(dn, M_PCPU); 218 } 219 sx_xunlock(&dpcpu_lock); 220 return; 221 } 222 if (df->df_start == end) { 223 df->df_start = start; 224 df->df_len += size; 225 sx_xunlock(&dpcpu_lock); 226 return; 227 } 228 } 229 dn = malloc(sizeof(*df), M_PCPU, M_WAITOK | M_ZERO); 230 dn->df_start = start; 231 dn->df_len = size; 232 if (df) 233 TAILQ_INSERT_BEFORE(df, dn, df_link); 234 else 235 TAILQ_INSERT_TAIL(&dpcpu_head, dn, df_link); 236 sx_xunlock(&dpcpu_lock); 237 } 238 239 /* 240 * Initialize the per-cpu storage from an updated linker-set region. 241 */ 242 void 243 dpcpu_copy(void *s, int size) 244 { 245 #ifdef SMP 246 uintptr_t dpcpu; 247 int i; 248 249 CPU_FOREACH(i) { 250 dpcpu = dpcpu_off[i]; 251 if (dpcpu == 0) 252 continue; 253 memcpy((void *)(dpcpu + (uintptr_t)s), s, size); 254 } 255 #else 256 memcpy((void *)(dpcpu_off[0] + (uintptr_t)s), s, size); 257 #endif 258 } 259 260 /* 261 * Destroy a struct pcpu. 262 */ 263 void 264 pcpu_destroy(struct pcpu *pcpu) 265 { 266 267 STAILQ_REMOVE(&cpuhead, pcpu, pcpu, pc_allcpu); 268 cpuid_to_pcpu[pcpu->pc_cpuid] = NULL; 269 dpcpu_off[pcpu->pc_cpuid] = 0; 270 } 271 272 /* 273 * Locate a struct pcpu by cpu id. 274 */ 275 struct pcpu * 276 pcpu_find(u_int cpuid) 277 { 278 279 return (cpuid_to_pcpu[cpuid]); 280 } 281 282 int 283 sysctl_dpcpu_quad(SYSCTL_HANDLER_ARGS) 284 { 285 uintptr_t dpcpu; 286 int64_t count; 287 int i; 288 289 count = 0; 290 CPU_FOREACH(i) { 291 dpcpu = dpcpu_off[i]; 292 if (dpcpu == 0) 293 continue; 294 count += *(int64_t *)(dpcpu + (uintptr_t)arg1); 295 } 296 return (SYSCTL_OUT(req, &count, sizeof(count))); 297 } 298 299 int 300 sysctl_dpcpu_long(SYSCTL_HANDLER_ARGS) 301 { 302 uintptr_t dpcpu; 303 long count; 304 int i; 305 306 count = 0; 307 CPU_FOREACH(i) { 308 dpcpu = dpcpu_off[i]; 309 if (dpcpu == 0) 310 continue; 311 count += *(long *)(dpcpu + (uintptr_t)arg1); 312 } 313 return (SYSCTL_OUT(req, &count, sizeof(count))); 314 } 315 316 int 317 sysctl_dpcpu_int(SYSCTL_HANDLER_ARGS) 318 { 319 uintptr_t dpcpu; 320 int count; 321 int i; 322 323 count = 0; 324 CPU_FOREACH(i) { 325 dpcpu = dpcpu_off[i]; 326 if (dpcpu == 0) 327 continue; 328 count += *(int *)(dpcpu + (uintptr_t)arg1); 329 } 330 return (SYSCTL_OUT(req, &count, sizeof(count))); 331 } 332 333 #ifdef DDB 334 DB_SHOW_COMMAND(dpcpu_off, db_show_dpcpu_off) 335 { 336 int id; 337 338 CPU_FOREACH(id) { 339 db_printf("dpcpu_off[%2d] = 0x%jx (+ DPCPU_START = %p)\n", 340 id, (uintmax_t)dpcpu_off[id], 341 (void *)(uintptr_t)(dpcpu_off[id] + DPCPU_START)); 342 } 343 } 344 345 static void 346 show_pcpu(struct pcpu *pc) 347 { 348 struct thread *td; 349 350 db_printf("cpuid = %d\n", pc->pc_cpuid); 351 db_printf("dynamic pcpu = %p\n", (void *)pc->pc_dynamic); 352 db_printf("curthread = "); 353 td = pc->pc_curthread; 354 if (td != NULL) 355 db_printf("%p: pid %d tid %d \"%s\"\n", td, td->td_proc->p_pid, 356 td->td_tid, td->td_name); 357 else 358 db_printf("none\n"); 359 db_printf("curpcb = %p\n", pc->pc_curpcb); 360 db_printf("fpcurthread = "); 361 td = pc->pc_fpcurthread; 362 if (td != NULL) 363 db_printf("%p: pid %d \"%s\"\n", td, td->td_proc->p_pid, 364 td->td_name); 365 else 366 db_printf("none\n"); 367 db_printf("idlethread = "); 368 td = pc->pc_idlethread; 369 if (td != NULL) 370 db_printf("%p: tid %d \"%s\"\n", td, td->td_tid, td->td_name); 371 else 372 db_printf("none\n"); 373 db_show_mdpcpu(pc); 374 375 #ifdef VIMAGE 376 db_printf("curvnet = %p\n", pc->pc_curthread->td_vnet); 377 #endif 378 379 #ifdef WITNESS 380 db_printf("spin locks held:\n"); 381 witness_list_locks(&pc->pc_spinlocks, db_printf); 382 #endif 383 } 384 385 DB_SHOW_COMMAND(pcpu, db_show_pcpu) 386 { 387 struct pcpu *pc; 388 int id; 389 390 if (have_addr) 391 id = ((addr >> 4) % 16) * 10 + (addr % 16); 392 else 393 id = PCPU_GET(cpuid); 394 pc = pcpu_find(id); 395 if (pc == NULL) { 396 db_printf("CPU %d not found\n", id); 397 return; 398 } 399 show_pcpu(pc); 400 } 401 402 DB_SHOW_ALL_COMMAND(pcpu, db_show_cpu_all) 403 { 404 struct pcpu *pc; 405 int id; 406 407 db_printf("Current CPU: %d\n\n", PCPU_GET(cpuid)); 408 CPU_FOREACH(id) { 409 pc = pcpu_find(id); 410 if (pc != NULL) { 411 show_pcpu(pc); 412 db_printf("\n"); 413 } 414 } 415 } 416 DB_SHOW_ALIAS(allpcpu, db_show_cpu_all); 417 #endif 418