1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2003-2008 Joseph Koshy 5 * Copyright (c) 2007 The FreeBSD Foundation 6 * Copyright (c) 2018 Matthew Macy 7 * All rights reserved. 8 * 9 * Portions of this software were developed by A. Joseph Koshy under 10 * sponsorship from the FreeBSD Foundation and Google, Inc. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 */ 34 35 #include <sys/cdefs.h> 36 __FBSDID("$FreeBSD$"); 37 38 #include <sys/param.h> 39 #include <sys/eventhandler.h> 40 #include <sys/gtaskqueue.h> 41 #include <sys/jail.h> 42 #include <sys/kernel.h> 43 #include <sys/kthread.h> 44 #include <sys/limits.h> 45 #include <sys/lock.h> 46 #include <sys/malloc.h> 47 #include <sys/module.h> 48 #include <sys/mount.h> 49 #include <sys/mutex.h> 50 #include <sys/pmc.h> 51 #include <sys/pmckern.h> 52 #include <sys/pmclog.h> 53 #include <sys/priv.h> 54 #include <sys/proc.h> 55 #include <sys/queue.h> 56 #include <sys/resourcevar.h> 57 #include <sys/rwlock.h> 58 #include <sys/sched.h> 59 #include <sys/signalvar.h> 60 #include <sys/smp.h> 61 #include <sys/sx.h> 62 #include <sys/sysctl.h> 63 #include <sys/sysent.h> 64 #include <sys/systm.h> 65 #include <sys/vnode.h> 66 67 #include <sys/linker.h> /* needs to be after <sys/malloc.h> */ 68 69 #include <machine/atomic.h> 70 #include <machine/md_var.h> 71 72 #include <vm/vm.h> 73 #include <vm/vm_extern.h> 74 #include <vm/pmap.h> 75 #include <vm/vm_map.h> 76 #include <vm/vm_object.h> 77 78 #include "hwpmc_soft.h" 79 80 #ifdef NUMA 81 #define NDOMAINS vm_ndomains 82 #else 83 #define NDOMAINS 1 84 #define malloc_domain(size, type, domain, flags) malloc((size), (type), (flags)) 85 #define free_domain(addr, type) free(addr, type) 86 #endif 87 88 /* 89 * Types 90 */ 91 92 enum pmc_flags { 93 PMC_FLAG_NONE = 0x00, /* do nothing */ 94 PMC_FLAG_REMOVE = 0x01, /* atomically remove entry from hash */ 95 PMC_FLAG_ALLOCATE = 0x02, /* add entry to hash if not found */ 96 PMC_FLAG_NOWAIT = 0x04, /* do not wait for mallocs */ 97 }; 98 99 /* 100 * The offset in sysent where the syscall is allocated. 101 */ 102 103 static int pmc_syscall_num = NO_SYSCALL; 104 struct pmc_cpu **pmc_pcpu; /* per-cpu state */ 105 pmc_value_t *pmc_pcpu_saved; /* saved PMC values: CSW handling */ 106 107 #define PMC_PCPU_SAVED(C,R) pmc_pcpu_saved[(R) + md->pmd_npmc*(C)] 108 109 struct mtx_pool *pmc_mtxpool; 110 static int *pmc_pmcdisp; /* PMC row dispositions */ 111 112 #define PMC_ROW_DISP_IS_FREE(R) (pmc_pmcdisp[(R)] == 0) 113 #define PMC_ROW_DISP_IS_THREAD(R) (pmc_pmcdisp[(R)] > 0) 114 #define PMC_ROW_DISP_IS_STANDALONE(R) (pmc_pmcdisp[(R)] < 0) 115 116 #define PMC_MARK_ROW_FREE(R) do { \ 117 pmc_pmcdisp[(R)] = 0; \ 118 } while (0) 119 120 #define PMC_MARK_ROW_STANDALONE(R) do { \ 121 KASSERT(pmc_pmcdisp[(R)] <= 0, ("[pmc,%d] row disposition error", \ 122 __LINE__)); \ 123 atomic_add_int(&pmc_pmcdisp[(R)], -1); \ 124 KASSERT(pmc_pmcdisp[(R)] >= (-pmc_cpu_max_active()), \ 125 ("[pmc,%d] row disposition error", __LINE__)); \ 126 } while (0) 127 128 #define PMC_UNMARK_ROW_STANDALONE(R) do { \ 129 atomic_add_int(&pmc_pmcdisp[(R)], 1); \ 130 KASSERT(pmc_pmcdisp[(R)] <= 0, ("[pmc,%d] row disposition error", \ 131 __LINE__)); \ 132 } while (0) 133 134 #define PMC_MARK_ROW_THREAD(R) do { \ 135 KASSERT(pmc_pmcdisp[(R)] >= 0, ("[pmc,%d] row disposition error", \ 136 __LINE__)); \ 137 atomic_add_int(&pmc_pmcdisp[(R)], 1); \ 138 } while (0) 139 140 #define PMC_UNMARK_ROW_THREAD(R) do { \ 141 atomic_add_int(&pmc_pmcdisp[(R)], -1); \ 142 KASSERT(pmc_pmcdisp[(R)] >= 0, ("[pmc,%d] row disposition error", \ 143 __LINE__)); \ 144 } while (0) 145 146 147 /* various event handlers */ 148 static eventhandler_tag pmc_exit_tag, pmc_fork_tag, pmc_kld_load_tag, 149 pmc_kld_unload_tag; 150 151 /* Module statistics */ 152 struct pmc_driverstats pmc_stats; 153 154 155 /* Machine/processor dependent operations */ 156 static struct pmc_mdep *md; 157 158 /* 159 * Hash tables mapping owner processes and target threads to PMCs. 160 */ 161 162 struct mtx pmc_processhash_mtx; /* spin mutex */ 163 static u_long pmc_processhashmask; 164 static LIST_HEAD(pmc_processhash, pmc_process) *pmc_processhash; 165 166 /* 167 * Hash table of PMC owner descriptors. This table is protected by 168 * the shared PMC "sx" lock. 169 */ 170 171 static u_long pmc_ownerhashmask; 172 static LIST_HEAD(pmc_ownerhash, pmc_owner) *pmc_ownerhash; 173 174 /* 175 * List of PMC owners with system-wide sampling PMCs. 176 */ 177 178 static CK_LIST_HEAD(, pmc_owner) pmc_ss_owners; 179 180 /* 181 * List of free thread entries. This is protected by the spin 182 * mutex. 183 */ 184 static struct mtx pmc_threadfreelist_mtx; /* spin mutex */ 185 static LIST_HEAD(, pmc_thread) pmc_threadfreelist; 186 static int pmc_threadfreelist_entries=0; 187 #define THREADENTRY_SIZE \ 188 (sizeof(struct pmc_thread) + (md->pmd_npmc * sizeof(struct pmc_threadpmcstate))) 189 190 /* 191 * Task to free thread descriptors 192 */ 193 static struct grouptask free_gtask; 194 195 /* 196 * A map of row indices to classdep structures. 197 */ 198 static struct pmc_classdep **pmc_rowindex_to_classdep; 199 200 /* 201 * Prototypes 202 */ 203 204 #ifdef HWPMC_DEBUG 205 static int pmc_debugflags_sysctl_handler(SYSCTL_HANDLER_ARGS); 206 static int pmc_debugflags_parse(char *newstr, char *fence); 207 #endif 208 209 static int load(struct module *module, int cmd, void *arg); 210 static int pmc_add_sample(int ring, struct pmc *pm, struct trapframe *tf); 211 static void pmc_add_thread_descriptors_from_proc(struct proc *p, 212 struct pmc_process *pp); 213 static int pmc_attach_process(struct proc *p, struct pmc *pm); 214 static struct pmc *pmc_allocate_pmc_descriptor(void); 215 static struct pmc_owner *pmc_allocate_owner_descriptor(struct proc *p); 216 static int pmc_attach_one_process(struct proc *p, struct pmc *pm); 217 static int pmc_can_allocate_rowindex(struct proc *p, unsigned int ri, 218 int cpu); 219 static int pmc_can_attach(struct pmc *pm, struct proc *p); 220 static void pmc_capture_user_callchain(int cpu, int soft, struct trapframe *tf); 221 static void pmc_cleanup(void); 222 static int pmc_detach_process(struct proc *p, struct pmc *pm); 223 static int pmc_detach_one_process(struct proc *p, struct pmc *pm, 224 int flags); 225 static void pmc_destroy_owner_descriptor(struct pmc_owner *po); 226 static void pmc_destroy_pmc_descriptor(struct pmc *pm); 227 static void pmc_destroy_process_descriptor(struct pmc_process *pp); 228 static struct pmc_owner *pmc_find_owner_descriptor(struct proc *p); 229 static int pmc_find_pmc(pmc_id_t pmcid, struct pmc **pm); 230 static struct pmc *pmc_find_pmc_descriptor_in_process(struct pmc_owner *po, 231 pmc_id_t pmc); 232 static struct pmc_process *pmc_find_process_descriptor(struct proc *p, 233 uint32_t mode); 234 static struct pmc_thread *pmc_find_thread_descriptor(struct pmc_process *pp, 235 struct thread *td, uint32_t mode); 236 static void pmc_force_context_switch(void); 237 static void pmc_link_target_process(struct pmc *pm, 238 struct pmc_process *pp); 239 static void pmc_log_all_process_mappings(struct pmc_owner *po); 240 static void pmc_log_kernel_mappings(struct pmc *pm); 241 static void pmc_log_process_mappings(struct pmc_owner *po, struct proc *p); 242 static void pmc_maybe_remove_owner(struct pmc_owner *po); 243 static void pmc_process_csw_in(struct thread *td); 244 static void pmc_process_csw_out(struct thread *td); 245 static void pmc_process_exit(void *arg, struct proc *p); 246 static void pmc_process_fork(void *arg, struct proc *p1, 247 struct proc *p2, int n); 248 static void pmc_process_samples(int cpu, int soft); 249 static void pmc_release_pmc_descriptor(struct pmc *pmc); 250 static void pmc_process_thread_add(struct thread *td); 251 static void pmc_process_thread_delete(struct thread *td); 252 static void pmc_process_thread_userret(struct thread *td); 253 static void pmc_remove_owner(struct pmc_owner *po); 254 static void pmc_remove_process_descriptor(struct pmc_process *pp); 255 static void pmc_restore_cpu_binding(struct pmc_binding *pb); 256 static void pmc_save_cpu_binding(struct pmc_binding *pb); 257 static void pmc_select_cpu(int cpu); 258 static int pmc_start(struct pmc *pm); 259 static int pmc_stop(struct pmc *pm); 260 static int pmc_syscall_handler(struct thread *td, void *syscall_args); 261 static struct pmc_thread *pmc_thread_descriptor_pool_alloc(void); 262 static void pmc_thread_descriptor_pool_drain(void); 263 static void pmc_thread_descriptor_pool_free(struct pmc_thread *pt); 264 static void pmc_unlink_target_process(struct pmc *pmc, 265 struct pmc_process *pp); 266 static int generic_switch_in(struct pmc_cpu *pc, struct pmc_process *pp); 267 static int generic_switch_out(struct pmc_cpu *pc, struct pmc_process *pp); 268 static struct pmc_mdep *pmc_generic_cpu_initialize(void); 269 static void pmc_generic_cpu_finalize(struct pmc_mdep *md); 270 static void pmc_post_callchain_callback(void); 271 static void pmc_process_threadcreate(struct thread *td); 272 static void pmc_process_threadexit(struct thread *td); 273 static void pmc_process_proccreate(struct proc *p); 274 static void pmc_process_allproc(struct pmc *pm); 275 276 /* 277 * Kernel tunables and sysctl(8) interface. 278 */ 279 280 SYSCTL_DECL(_kern_hwpmc); 281 SYSCTL_NODE(_kern_hwpmc, OID_AUTO, stats, CTLFLAG_RW, 0, "HWPMC stats"); 282 283 284 /* Stats. */ 285 SYSCTL_COUNTER_U64(_kern_hwpmc_stats, OID_AUTO, intr_ignored, CTLFLAG_RW, 286 &pmc_stats.pm_intr_ignored, "# of interrupts ignored"); 287 SYSCTL_COUNTER_U64(_kern_hwpmc_stats, OID_AUTO, intr_processed, CTLFLAG_RW, 288 &pmc_stats.pm_intr_processed, "# of interrupts processed"); 289 SYSCTL_COUNTER_U64(_kern_hwpmc_stats, OID_AUTO, intr_bufferfull, CTLFLAG_RW, 290 &pmc_stats.pm_intr_bufferfull, "# of interrupts where buffer was full"); 291 SYSCTL_COUNTER_U64(_kern_hwpmc_stats, OID_AUTO, syscalls, CTLFLAG_RW, 292 &pmc_stats.pm_syscalls, "# of syscalls"); 293 SYSCTL_COUNTER_U64(_kern_hwpmc_stats, OID_AUTO, syscall_errors, CTLFLAG_RW, 294 &pmc_stats.pm_syscall_errors, "# of syscall_errors"); 295 SYSCTL_COUNTER_U64(_kern_hwpmc_stats, OID_AUTO, buffer_requests, CTLFLAG_RW, 296 &pmc_stats.pm_buffer_requests, "# of buffer requests"); 297 SYSCTL_COUNTER_U64(_kern_hwpmc_stats, OID_AUTO, buffer_requests_failed, CTLFLAG_RW, 298 &pmc_stats.pm_buffer_requests_failed, "# of buffer requests which failed"); 299 SYSCTL_COUNTER_U64(_kern_hwpmc_stats, OID_AUTO, log_sweeps, CTLFLAG_RW, 300 &pmc_stats.pm_log_sweeps, "# of ?"); 301 SYSCTL_COUNTER_U64(_kern_hwpmc_stats, OID_AUTO, merges, CTLFLAG_RW, 302 &pmc_stats.pm_merges, "# of times kernel stack was found for user trace"); 303 SYSCTL_COUNTER_U64(_kern_hwpmc_stats, OID_AUTO, overwrites, CTLFLAG_RW, 304 &pmc_stats.pm_overwrites, "# of times a sample was overwritten before being logged"); 305 306 static int pmc_callchaindepth = PMC_CALLCHAIN_DEPTH; 307 SYSCTL_INT(_kern_hwpmc, OID_AUTO, callchaindepth, CTLFLAG_RDTUN, 308 &pmc_callchaindepth, 0, "depth of call chain records"); 309 310 char pmc_cpuid[64]; 311 SYSCTL_STRING(_kern_hwpmc, OID_AUTO, cpuid, CTLFLAG_RD, 312 pmc_cpuid, 0, "cpu version string"); 313 #ifdef HWPMC_DEBUG 314 struct pmc_debugflags pmc_debugflags = PMC_DEBUG_DEFAULT_FLAGS; 315 char pmc_debugstr[PMC_DEBUG_STRSIZE]; 316 TUNABLE_STR(PMC_SYSCTL_NAME_PREFIX "debugflags", pmc_debugstr, 317 sizeof(pmc_debugstr)); 318 SYSCTL_PROC(_kern_hwpmc, OID_AUTO, debugflags, 319 CTLTYPE_STRING | CTLFLAG_RWTUN | CTLFLAG_NOFETCH, 320 0, 0, pmc_debugflags_sysctl_handler, "A", "debug flags"); 321 #endif 322 323 324 /* 325 * kern.hwpmc.hashrows -- determines the number of rows in the 326 * of the hash table used to look up threads 327 */ 328 329 static int pmc_hashsize = PMC_HASH_SIZE; 330 SYSCTL_INT(_kern_hwpmc, OID_AUTO, hashsize, CTLFLAG_RDTUN, 331 &pmc_hashsize, 0, "rows in hash tables"); 332 333 /* 334 * kern.hwpmc.nsamples --- number of PC samples/callchain stacks per CPU 335 */ 336 337 static int pmc_nsamples = PMC_NSAMPLES; 338 SYSCTL_INT(_kern_hwpmc, OID_AUTO, nsamples, CTLFLAG_RDTUN, 339 &pmc_nsamples, 0, "number of PC samples per CPU"); 340 341 342 /* 343 * kern.hwpmc.mtxpoolsize -- number of mutexes in the mutex pool. 344 */ 345 346 static int pmc_mtxpool_size = PMC_MTXPOOL_SIZE; 347 SYSCTL_INT(_kern_hwpmc, OID_AUTO, mtxpoolsize, CTLFLAG_RDTUN, 348 &pmc_mtxpool_size, 0, "size of spin mutex pool"); 349 350 351 /* 352 * kern.hwpmc.threadfreelist_entries -- number of free entries 353 */ 354 355 SYSCTL_INT(_kern_hwpmc, OID_AUTO, threadfreelist_entries, CTLFLAG_RD, 356 &pmc_threadfreelist_entries, 0, "number of avalable thread entries"); 357 358 359 /* 360 * kern.hwpmc.threadfreelist_max -- maximum number of free entries 361 */ 362 363 static int pmc_threadfreelist_max = PMC_THREADLIST_MAX; 364 SYSCTL_INT(_kern_hwpmc, OID_AUTO, threadfreelist_max, CTLFLAG_RW, 365 &pmc_threadfreelist_max, 0, 366 "maximum number of available thread entries before freeing some"); 367 368 369 /* 370 * security.bsd.unprivileged_syspmcs -- allow non-root processes to 371 * allocate system-wide PMCs. 372 * 373 * Allowing unprivileged processes to allocate system PMCs is convenient 374 * if system-wide measurements need to be taken concurrently with other 375 * per-process measurements. This feature is turned off by default. 376 */ 377 378 static int pmc_unprivileged_syspmcs = 0; 379 SYSCTL_INT(_security_bsd, OID_AUTO, unprivileged_syspmcs, CTLFLAG_RWTUN, 380 &pmc_unprivileged_syspmcs, 0, 381 "allow unprivileged process to allocate system PMCs"); 382 383 /* 384 * Hash function. Discard the lower 2 bits of the pointer since 385 * these are always zero for our uses. The hash multiplier is 386 * round((2^LONG_BIT) * ((sqrt(5)-1)/2)). 387 */ 388 389 #if LONG_BIT == 64 390 #define _PMC_HM 11400714819323198486u 391 #elif LONG_BIT == 32 392 #define _PMC_HM 2654435769u 393 #else 394 #error Must know the size of 'long' to compile 395 #endif 396 397 #define PMC_HASH_PTR(P,M) ((((unsigned long) (P) >> 2) * _PMC_HM) & (M)) 398 399 /* 400 * Syscall structures 401 */ 402 403 /* The `sysent' for the new syscall */ 404 static struct sysent pmc_sysent = { 405 .sy_narg = 2, 406 .sy_call = pmc_syscall_handler, 407 }; 408 409 static struct syscall_module_data pmc_syscall_mod = { 410 .chainevh = load, 411 .chainarg = NULL, 412 .offset = &pmc_syscall_num, 413 .new_sysent = &pmc_sysent, 414 .old_sysent = { .sy_narg = 0, .sy_call = NULL }, 415 .flags = SY_THR_STATIC_KLD, 416 }; 417 418 static moduledata_t pmc_mod = { 419 .name = PMC_MODULE_NAME, 420 .evhand = syscall_module_handler, 421 .priv = &pmc_syscall_mod, 422 }; 423 424 #ifdef EARLY_AP_STARTUP 425 DECLARE_MODULE(pmc, pmc_mod, SI_SUB_SYSCALLS, SI_ORDER_ANY); 426 #else 427 DECLARE_MODULE(pmc, pmc_mod, SI_SUB_SMP, SI_ORDER_ANY); 428 #endif 429 MODULE_VERSION(pmc, PMC_VERSION); 430 431 #ifdef HWPMC_DEBUG 432 enum pmc_dbgparse_state { 433 PMCDS_WS, /* in whitespace */ 434 PMCDS_MAJOR, /* seen a major keyword */ 435 PMCDS_MINOR 436 }; 437 438 static int 439 pmc_debugflags_parse(char *newstr, char *fence) 440 { 441 char c, *p, *q; 442 struct pmc_debugflags *tmpflags; 443 int error, found, *newbits, tmp; 444 size_t kwlen; 445 446 tmpflags = malloc(sizeof(*tmpflags), M_PMC, M_WAITOK|M_ZERO); 447 448 p = newstr; 449 error = 0; 450 451 for (; p < fence && (c = *p); p++) { 452 453 /* skip white space */ 454 if (c == ' ' || c == '\t') 455 continue; 456 457 /* look for a keyword followed by "=" */ 458 for (q = p; p < fence && (c = *p) && c != '='; p++) 459 ; 460 if (c != '=') { 461 error = EINVAL; 462 goto done; 463 } 464 465 kwlen = p - q; 466 newbits = NULL; 467 468 /* lookup flag group name */ 469 #define DBG_SET_FLAG_MAJ(S,F) \ 470 if (kwlen == sizeof(S)-1 && strncmp(q, S, kwlen) == 0) \ 471 newbits = &tmpflags->pdb_ ## F; 472 473 DBG_SET_FLAG_MAJ("cpu", CPU); 474 DBG_SET_FLAG_MAJ("csw", CSW); 475 DBG_SET_FLAG_MAJ("logging", LOG); 476 DBG_SET_FLAG_MAJ("module", MOD); 477 DBG_SET_FLAG_MAJ("md", MDP); 478 DBG_SET_FLAG_MAJ("owner", OWN); 479 DBG_SET_FLAG_MAJ("pmc", PMC); 480 DBG_SET_FLAG_MAJ("process", PRC); 481 DBG_SET_FLAG_MAJ("sampling", SAM); 482 483 if (newbits == NULL) { 484 error = EINVAL; 485 goto done; 486 } 487 488 p++; /* skip the '=' */ 489 490 /* Now parse the individual flags */ 491 tmp = 0; 492 newflag: 493 for (q = p; p < fence && (c = *p); p++) 494 if (c == ' ' || c == '\t' || c == ',') 495 break; 496 497 /* p == fence or c == ws or c == "," or c == 0 */ 498 499 if ((kwlen = p - q) == 0) { 500 *newbits = tmp; 501 continue; 502 } 503 504 found = 0; 505 #define DBG_SET_FLAG_MIN(S,F) \ 506 if (kwlen == sizeof(S)-1 && strncmp(q, S, kwlen) == 0) \ 507 tmp |= found = (1 << PMC_DEBUG_MIN_ ## F) 508 509 /* a '*' denotes all possible flags in the group */ 510 if (kwlen == 1 && *q == '*') 511 tmp = found = ~0; 512 /* look for individual flag names */ 513 DBG_SET_FLAG_MIN("allocaterow", ALR); 514 DBG_SET_FLAG_MIN("allocate", ALL); 515 DBG_SET_FLAG_MIN("attach", ATT); 516 DBG_SET_FLAG_MIN("bind", BND); 517 DBG_SET_FLAG_MIN("config", CFG); 518 DBG_SET_FLAG_MIN("exec", EXC); 519 DBG_SET_FLAG_MIN("exit", EXT); 520 DBG_SET_FLAG_MIN("find", FND); 521 DBG_SET_FLAG_MIN("flush", FLS); 522 DBG_SET_FLAG_MIN("fork", FRK); 523 DBG_SET_FLAG_MIN("getbuf", GTB); 524 DBG_SET_FLAG_MIN("hook", PMH); 525 DBG_SET_FLAG_MIN("init", INI); 526 DBG_SET_FLAG_MIN("intr", INT); 527 DBG_SET_FLAG_MIN("linktarget", TLK); 528 DBG_SET_FLAG_MIN("mayberemove", OMR); 529 DBG_SET_FLAG_MIN("ops", OPS); 530 DBG_SET_FLAG_MIN("read", REA); 531 DBG_SET_FLAG_MIN("register", REG); 532 DBG_SET_FLAG_MIN("release", REL); 533 DBG_SET_FLAG_MIN("remove", ORM); 534 DBG_SET_FLAG_MIN("sample", SAM); 535 DBG_SET_FLAG_MIN("scheduleio", SIO); 536 DBG_SET_FLAG_MIN("select", SEL); 537 DBG_SET_FLAG_MIN("signal", SIG); 538 DBG_SET_FLAG_MIN("swi", SWI); 539 DBG_SET_FLAG_MIN("swo", SWO); 540 DBG_SET_FLAG_MIN("start", STA); 541 DBG_SET_FLAG_MIN("stop", STO); 542 DBG_SET_FLAG_MIN("syscall", PMS); 543 DBG_SET_FLAG_MIN("unlinktarget", TUL); 544 DBG_SET_FLAG_MIN("write", WRI); 545 if (found == 0) { 546 /* unrecognized flag name */ 547 error = EINVAL; 548 goto done; 549 } 550 551 if (c == 0 || c == ' ' || c == '\t') { /* end of flag group */ 552 *newbits = tmp; 553 continue; 554 } 555 556 p++; 557 goto newflag; 558 } 559 560 /* save the new flag set */ 561 bcopy(tmpflags, &pmc_debugflags, sizeof(pmc_debugflags)); 562 563 done: 564 free(tmpflags, M_PMC); 565 return error; 566 } 567 568 static int 569 pmc_debugflags_sysctl_handler(SYSCTL_HANDLER_ARGS) 570 { 571 char *fence, *newstr; 572 int error; 573 unsigned int n; 574 575 (void) arg1; (void) arg2; /* unused parameters */ 576 577 n = sizeof(pmc_debugstr); 578 newstr = malloc(n, M_PMC, M_WAITOK|M_ZERO); 579 (void) strlcpy(newstr, pmc_debugstr, n); 580 581 error = sysctl_handle_string(oidp, newstr, n, req); 582 583 /* if there is a new string, parse and copy it */ 584 if (error == 0 && req->newptr != NULL) { 585 fence = newstr + (n < req->newlen ? n : req->newlen + 1); 586 if ((error = pmc_debugflags_parse(newstr, fence)) == 0) 587 (void) strlcpy(pmc_debugstr, newstr, 588 sizeof(pmc_debugstr)); 589 } 590 591 free(newstr, M_PMC); 592 593 return error; 594 } 595 #endif 596 597 /* 598 * Map a row index to a classdep structure and return the adjusted row 599 * index for the PMC class index. 600 */ 601 static struct pmc_classdep * 602 pmc_ri_to_classdep(struct pmc_mdep *md, int ri, int *adjri) 603 { 604 struct pmc_classdep *pcd; 605 606 (void) md; 607 608 KASSERT(ri >= 0 && ri < md->pmd_npmc, 609 ("[pmc,%d] illegal row-index %d", __LINE__, ri)); 610 611 pcd = pmc_rowindex_to_classdep[ri]; 612 613 KASSERT(pcd != NULL, 614 ("[pmc,%d] ri %d null pcd", __LINE__, ri)); 615 616 *adjri = ri - pcd->pcd_ri; 617 618 KASSERT(*adjri >= 0 && *adjri < pcd->pcd_num, 619 ("[pmc,%d] adjusted row-index %d", __LINE__, *adjri)); 620 621 return (pcd); 622 } 623 624 /* 625 * Concurrency Control 626 * 627 * The driver manages the following data structures: 628 * 629 * - target process descriptors, one per target process 630 * - owner process descriptors (and attached lists), one per owner process 631 * - lookup hash tables for owner and target processes 632 * - PMC descriptors (and attached lists) 633 * - per-cpu hardware state 634 * - the 'hook' variable through which the kernel calls into 635 * this module 636 * - the machine hardware state (managed by the MD layer) 637 * 638 * These data structures are accessed from: 639 * 640 * - thread context-switch code 641 * - interrupt handlers (possibly on multiple cpus) 642 * - kernel threads on multiple cpus running on behalf of user 643 * processes doing system calls 644 * - this driver's private kernel threads 645 * 646 * = Locks and Locking strategy = 647 * 648 * The driver uses four locking strategies for its operation: 649 * 650 * - The global SX lock "pmc_sx" is used to protect internal 651 * data structures. 652 * 653 * Calls into the module by syscall() start with this lock being 654 * held in exclusive mode. Depending on the requested operation, 655 * the lock may be downgraded to 'shared' mode to allow more 656 * concurrent readers into the module. Calls into the module from 657 * other parts of the kernel acquire the lock in shared mode. 658 * 659 * This SX lock is held in exclusive mode for any operations that 660 * modify the linkages between the driver's internal data structures. 661 * 662 * The 'pmc_hook' function pointer is also protected by this lock. 663 * It is only examined with the sx lock held in exclusive mode. The 664 * kernel module is allowed to be unloaded only with the sx lock held 665 * in exclusive mode. In normal syscall handling, after acquiring the 666 * pmc_sx lock we first check that 'pmc_hook' is non-null before 667 * proceeding. This prevents races between the thread unloading the module 668 * and other threads seeking to use the module. 669 * 670 * - Lookups of target process structures and owner process structures 671 * cannot use the global "pmc_sx" SX lock because these lookups need 672 * to happen during context switches and in other critical sections 673 * where sleeping is not allowed. We protect these lookup tables 674 * with their own private spin-mutexes, "pmc_processhash_mtx" and 675 * "pmc_ownerhash_mtx". 676 * 677 * - Interrupt handlers work in a lock free manner. At interrupt 678 * time, handlers look at the PMC pointer (phw->phw_pmc) configured 679 * when the PMC was started. If this pointer is NULL, the interrupt 680 * is ignored after updating driver statistics. We ensure that this 681 * pointer is set (using an atomic operation if necessary) before the 682 * PMC hardware is started. Conversely, this pointer is unset atomically 683 * only after the PMC hardware is stopped. 684 * 685 * We ensure that everything needed for the operation of an 686 * interrupt handler is available without it needing to acquire any 687 * locks. We also ensure that a PMC's software state is destroyed only 688 * after the PMC is taken off hardware (on all CPUs). 689 * 690 * - Context-switch handling with process-private PMCs needs more 691 * care. 692 * 693 * A given process may be the target of multiple PMCs. For example, 694 * PMCATTACH and PMCDETACH may be requested by a process on one CPU 695 * while the target process is running on another. A PMC could also 696 * be getting released because its owner is exiting. We tackle 697 * these situations in the following manner: 698 * 699 * - each target process structure 'pmc_process' has an array 700 * of 'struct pmc *' pointers, one for each hardware PMC. 701 * 702 * - At context switch IN time, each "target" PMC in RUNNING state 703 * gets started on hardware and a pointer to each PMC is copied into 704 * the per-cpu phw array. The 'runcount' for the PMC is 705 * incremented. 706 * 707 * - At context switch OUT time, all process-virtual PMCs are stopped 708 * on hardware. The saved value is added to the PMCs value field 709 * only if the PMC is in a non-deleted state (the PMCs state could 710 * have changed during the current time slice). 711 * 712 * Note that since in-between a switch IN on a processor and a switch 713 * OUT, the PMC could have been released on another CPU. Therefore 714 * context switch OUT always looks at the hardware state to turn 715 * OFF PMCs and will update a PMC's saved value only if reachable 716 * from the target process record. 717 * 718 * - OP PMCRELEASE could be called on a PMC at any time (the PMC could 719 * be attached to many processes at the time of the call and could 720 * be active on multiple CPUs). 721 * 722 * We prevent further scheduling of the PMC by marking it as in 723 * state 'DELETED'. If the runcount of the PMC is non-zero then 724 * this PMC is currently running on a CPU somewhere. The thread 725 * doing the PMCRELEASE operation waits by repeatedly doing a 726 * pause() till the runcount comes to zero. 727 * 728 * The contents of a PMC descriptor (struct pmc) are protected using 729 * a spin-mutex. In order to save space, we use a mutex pool. 730 * 731 * In terms of lock types used by witness(4), we use: 732 * - Type "pmc-sx", used by the global SX lock. 733 * - Type "pmc-sleep", for sleep mutexes used by logger threads. 734 * - Type "pmc-per-proc", for protecting PMC owner descriptors. 735 * - Type "pmc-leaf", used for all other spin mutexes. 736 */ 737 738 /* 739 * save the cpu binding of the current kthread 740 */ 741 742 static void 743 pmc_save_cpu_binding(struct pmc_binding *pb) 744 { 745 PMCDBG0(CPU,BND,2, "save-cpu"); 746 thread_lock(curthread); 747 pb->pb_bound = sched_is_bound(curthread); 748 pb->pb_cpu = curthread->td_oncpu; 749 thread_unlock(curthread); 750 PMCDBG1(CPU,BND,2, "save-cpu cpu=%d", pb->pb_cpu); 751 } 752 753 /* 754 * restore the cpu binding of the current thread 755 */ 756 757 static void 758 pmc_restore_cpu_binding(struct pmc_binding *pb) 759 { 760 PMCDBG2(CPU,BND,2, "restore-cpu curcpu=%d restore=%d", 761 curthread->td_oncpu, pb->pb_cpu); 762 thread_lock(curthread); 763 if (pb->pb_bound) 764 sched_bind(curthread, pb->pb_cpu); 765 else 766 sched_unbind(curthread); 767 thread_unlock(curthread); 768 PMCDBG0(CPU,BND,2, "restore-cpu done"); 769 } 770 771 /* 772 * move execution over the specified cpu and bind it there. 773 */ 774 775 static void 776 pmc_select_cpu(int cpu) 777 { 778 KASSERT(cpu >= 0 && cpu < pmc_cpu_max(), 779 ("[pmc,%d] bad cpu number %d", __LINE__, cpu)); 780 781 /* Never move to an inactive CPU. */ 782 KASSERT(pmc_cpu_is_active(cpu), ("[pmc,%d] selecting inactive " 783 "CPU %d", __LINE__, cpu)); 784 785 PMCDBG1(CPU,SEL,2, "select-cpu cpu=%d", cpu); 786 thread_lock(curthread); 787 sched_bind(curthread, cpu); 788 thread_unlock(curthread); 789 790 KASSERT(curthread->td_oncpu == cpu, 791 ("[pmc,%d] CPU not bound [cpu=%d, curr=%d]", __LINE__, 792 cpu, curthread->td_oncpu)); 793 794 PMCDBG1(CPU,SEL,2, "select-cpu cpu=%d ok", cpu); 795 } 796 797 /* 798 * Force a context switch. 799 * 800 * We do this by pause'ing for 1 tick -- invoking mi_switch() is not 801 * guaranteed to force a context switch. 802 */ 803 804 static void 805 pmc_force_context_switch(void) 806 { 807 808 pause("pmcctx", 1); 809 } 810 811 uint64_t 812 pmc_rdtsc(void) 813 { 814 #if defined(__i386__) || defined(__amd64__) 815 if (__predict_true(amd_feature & AMDID_RDTSCP)) 816 return rdtscp(); 817 else 818 return rdtsc(); 819 #else 820 return get_cyclecount(); 821 #endif 822 } 823 824 /* 825 * Get the file name for an executable. This is a simple wrapper 826 * around vn_fullpath(9). 827 */ 828 829 static void 830 pmc_getfilename(struct vnode *v, char **fullpath, char **freepath) 831 { 832 833 *fullpath = "unknown"; 834 *freepath = NULL; 835 vn_fullpath(curthread, v, fullpath, freepath); 836 } 837 838 /* 839 * remove an process owning PMCs 840 */ 841 842 void 843 pmc_remove_owner(struct pmc_owner *po) 844 { 845 struct pmc *pm, *tmp; 846 847 sx_assert(&pmc_sx, SX_XLOCKED); 848 849 PMCDBG1(OWN,ORM,1, "remove-owner po=%p", po); 850 851 /* Remove descriptor from the owner hash table */ 852 LIST_REMOVE(po, po_next); 853 854 /* release all owned PMC descriptors */ 855 LIST_FOREACH_SAFE(pm, &po->po_pmcs, pm_next, tmp) { 856 PMCDBG1(OWN,ORM,2, "pmc=%p", pm); 857 KASSERT(pm->pm_owner == po, 858 ("[pmc,%d] owner %p != po %p", __LINE__, pm->pm_owner, po)); 859 860 pmc_release_pmc_descriptor(pm); /* will unlink from the list */ 861 pmc_destroy_pmc_descriptor(pm); 862 } 863 864 KASSERT(po->po_sscount == 0, 865 ("[pmc,%d] SS count not zero", __LINE__)); 866 KASSERT(LIST_EMPTY(&po->po_pmcs), 867 ("[pmc,%d] PMC list not empty", __LINE__)); 868 869 /* de-configure the log file if present */ 870 if (po->po_flags & PMC_PO_OWNS_LOGFILE) 871 pmclog_deconfigure_log(po); 872 } 873 874 /* 875 * remove an owner process record if all conditions are met. 876 */ 877 878 static void 879 pmc_maybe_remove_owner(struct pmc_owner *po) 880 { 881 882 PMCDBG1(OWN,OMR,1, "maybe-remove-owner po=%p", po); 883 884 /* 885 * Remove owner record if 886 * - this process does not own any PMCs 887 * - this process has not allocated a system-wide sampling buffer 888 */ 889 890 if (LIST_EMPTY(&po->po_pmcs) && 891 ((po->po_flags & PMC_PO_OWNS_LOGFILE) == 0)) { 892 pmc_remove_owner(po); 893 pmc_destroy_owner_descriptor(po); 894 } 895 } 896 897 /* 898 * Add an association between a target process and a PMC. 899 */ 900 901 static void 902 pmc_link_target_process(struct pmc *pm, struct pmc_process *pp) 903 { 904 int ri; 905 struct pmc_target *pt; 906 #ifdef INVARIANTS 907 struct pmc_thread *pt_td; 908 #endif 909 910 sx_assert(&pmc_sx, SX_XLOCKED); 911 912 KASSERT(pm != NULL && pp != NULL, 913 ("[pmc,%d] Null pm %p or pp %p", __LINE__, pm, pp)); 914 KASSERT(PMC_IS_VIRTUAL_MODE(PMC_TO_MODE(pm)), 915 ("[pmc,%d] Attaching a non-process-virtual pmc=%p to pid=%d", 916 __LINE__, pm, pp->pp_proc->p_pid)); 917 KASSERT(pp->pp_refcnt >= 0 && pp->pp_refcnt <= ((int) md->pmd_npmc - 1), 918 ("[pmc,%d] Illegal reference count %d for process record %p", 919 __LINE__, pp->pp_refcnt, (void *) pp)); 920 921 ri = PMC_TO_ROWINDEX(pm); 922 923 PMCDBG3(PRC,TLK,1, "link-target pmc=%p ri=%d pmc-process=%p", 924 pm, ri, pp); 925 926 #ifdef HWPMC_DEBUG 927 LIST_FOREACH(pt, &pm->pm_targets, pt_next) 928 if (pt->pt_process == pp) 929 KASSERT(0, ("[pmc,%d] pp %p already in pmc %p targets", 930 __LINE__, pp, pm)); 931 #endif 932 933 pt = malloc(sizeof(struct pmc_target), M_PMC, M_WAITOK|M_ZERO); 934 pt->pt_process = pp; 935 936 LIST_INSERT_HEAD(&pm->pm_targets, pt, pt_next); 937 938 atomic_store_rel_ptr((uintptr_t *)&pp->pp_pmcs[ri].pp_pmc, 939 (uintptr_t)pm); 940 941 if (pm->pm_owner->po_owner == pp->pp_proc) 942 pm->pm_flags |= PMC_F_ATTACHED_TO_OWNER; 943 944 /* 945 * Initialize the per-process values at this row index. 946 */ 947 pp->pp_pmcs[ri].pp_pmcval = PMC_TO_MODE(pm) == PMC_MODE_TS ? 948 pm->pm_sc.pm_reloadcount : 0; 949 950 pp->pp_refcnt++; 951 952 #ifdef INVARIANTS 953 /* Confirm that the per-thread values at this row index are cleared. */ 954 if (PMC_TO_MODE(pm) == PMC_MODE_TS) { 955 mtx_lock_spin(pp->pp_tdslock); 956 LIST_FOREACH(pt_td, &pp->pp_tds, pt_next) { 957 KASSERT(pt_td->pt_pmcs[ri].pt_pmcval == (pmc_value_t) 0, 958 ("[pmc,%d] pt_pmcval not cleared for pid=%d at " 959 "ri=%d", __LINE__, pp->pp_proc->p_pid, ri)); 960 } 961 mtx_unlock_spin(pp->pp_tdslock); 962 } 963 #endif 964 } 965 966 /* 967 * Removes the association between a target process and a PMC. 968 */ 969 970 static void 971 pmc_unlink_target_process(struct pmc *pm, struct pmc_process *pp) 972 { 973 int ri; 974 struct proc *p; 975 struct pmc_target *ptgt; 976 struct pmc_thread *pt; 977 978 sx_assert(&pmc_sx, SX_XLOCKED); 979 980 KASSERT(pm != NULL && pp != NULL, 981 ("[pmc,%d] Null pm %p or pp %p", __LINE__, pm, pp)); 982 983 KASSERT(pp->pp_refcnt >= 1 && pp->pp_refcnt <= (int) md->pmd_npmc, 984 ("[pmc,%d] Illegal ref count %d on process record %p", 985 __LINE__, pp->pp_refcnt, (void *) pp)); 986 987 ri = PMC_TO_ROWINDEX(pm); 988 989 PMCDBG3(PRC,TUL,1, "unlink-target pmc=%p ri=%d pmc-process=%p", 990 pm, ri, pp); 991 992 KASSERT(pp->pp_pmcs[ri].pp_pmc == pm, 993 ("[pmc,%d] PMC ri %d mismatch pmc %p pp->[ri] %p", __LINE__, 994 ri, pm, pp->pp_pmcs[ri].pp_pmc)); 995 996 pp->pp_pmcs[ri].pp_pmc = NULL; 997 pp->pp_pmcs[ri].pp_pmcval = (pmc_value_t) 0; 998 999 /* Clear the per-thread values at this row index. */ 1000 if (PMC_TO_MODE(pm) == PMC_MODE_TS) { 1001 mtx_lock_spin(pp->pp_tdslock); 1002 LIST_FOREACH(pt, &pp->pp_tds, pt_next) 1003 pt->pt_pmcs[ri].pt_pmcval = (pmc_value_t) 0; 1004 mtx_unlock_spin(pp->pp_tdslock); 1005 } 1006 1007 /* Remove owner-specific flags */ 1008 if (pm->pm_owner->po_owner == pp->pp_proc) { 1009 pp->pp_flags &= ~PMC_PP_ENABLE_MSR_ACCESS; 1010 pm->pm_flags &= ~PMC_F_ATTACHED_TO_OWNER; 1011 } 1012 1013 pp->pp_refcnt--; 1014 1015 /* Remove the target process from the PMC structure */ 1016 LIST_FOREACH(ptgt, &pm->pm_targets, pt_next) 1017 if (ptgt->pt_process == pp) 1018 break; 1019 1020 KASSERT(ptgt != NULL, ("[pmc,%d] process %p (pp: %p) not found " 1021 "in pmc %p", __LINE__, pp->pp_proc, pp, pm)); 1022 1023 LIST_REMOVE(ptgt, pt_next); 1024 free(ptgt, M_PMC); 1025 1026 /* if the PMC now lacks targets, send the owner a SIGIO */ 1027 if (LIST_EMPTY(&pm->pm_targets)) { 1028 p = pm->pm_owner->po_owner; 1029 PROC_LOCK(p); 1030 kern_psignal(p, SIGIO); 1031 PROC_UNLOCK(p); 1032 1033 PMCDBG2(PRC,SIG,2, "signalling proc=%p signal=%d", p, 1034 SIGIO); 1035 } 1036 } 1037 1038 /* 1039 * Check if PMC 'pm' may be attached to target process 't'. 1040 */ 1041 1042 static int 1043 pmc_can_attach(struct pmc *pm, struct proc *t) 1044 { 1045 struct proc *o; /* pmc owner */ 1046 struct ucred *oc, *tc; /* owner, target credentials */ 1047 int decline_attach, i; 1048 1049 /* 1050 * A PMC's owner can always attach that PMC to itself. 1051 */ 1052 1053 if ((o = pm->pm_owner->po_owner) == t) 1054 return 0; 1055 1056 PROC_LOCK(o); 1057 oc = o->p_ucred; 1058 crhold(oc); 1059 PROC_UNLOCK(o); 1060 1061 PROC_LOCK(t); 1062 tc = t->p_ucred; 1063 crhold(tc); 1064 PROC_UNLOCK(t); 1065 1066 /* 1067 * The effective uid of the PMC owner should match at least one 1068 * of the {effective,real,saved} uids of the target process. 1069 */ 1070 1071 decline_attach = oc->cr_uid != tc->cr_uid && 1072 oc->cr_uid != tc->cr_svuid && 1073 oc->cr_uid != tc->cr_ruid; 1074 1075 /* 1076 * Every one of the target's group ids, must be in the owner's 1077 * group list. 1078 */ 1079 for (i = 0; !decline_attach && i < tc->cr_ngroups; i++) 1080 decline_attach = !groupmember(tc->cr_groups[i], oc); 1081 1082 /* check the read and saved gids too */ 1083 if (decline_attach == 0) 1084 decline_attach = !groupmember(tc->cr_rgid, oc) || 1085 !groupmember(tc->cr_svgid, oc); 1086 1087 crfree(tc); 1088 crfree(oc); 1089 1090 return !decline_attach; 1091 } 1092 1093 /* 1094 * Attach a process to a PMC. 1095 */ 1096 1097 static int 1098 pmc_attach_one_process(struct proc *p, struct pmc *pm) 1099 { 1100 int ri, error; 1101 char *fullpath, *freepath; 1102 struct pmc_process *pp; 1103 1104 sx_assert(&pmc_sx, SX_XLOCKED); 1105 1106 PMCDBG5(PRC,ATT,2, "attach-one pm=%p ri=%d proc=%p (%d, %s)", pm, 1107 PMC_TO_ROWINDEX(pm), p, p->p_pid, p->p_comm); 1108 1109 /* 1110 * Locate the process descriptor corresponding to process 'p', 1111 * allocating space as needed. 1112 * 1113 * Verify that rowindex 'pm_rowindex' is free in the process 1114 * descriptor. 1115 * 1116 * If not, allocate space for a descriptor and link the 1117 * process descriptor and PMC. 1118 */ 1119 ri = PMC_TO_ROWINDEX(pm); 1120 1121 /* mark process as using HWPMCs */ 1122 PROC_LOCK(p); 1123 p->p_flag |= P_HWPMC; 1124 PROC_UNLOCK(p); 1125 1126 if ((pp = pmc_find_process_descriptor(p, PMC_FLAG_ALLOCATE)) == NULL) { 1127 error = ENOMEM; 1128 goto fail; 1129 } 1130 1131 if (pp->pp_pmcs[ri].pp_pmc == pm) {/* already present at slot [ri] */ 1132 error = EEXIST; 1133 goto fail; 1134 } 1135 1136 if (pp->pp_pmcs[ri].pp_pmc != NULL) { 1137 error = EBUSY; 1138 goto fail; 1139 } 1140 1141 pmc_link_target_process(pm, pp); 1142 1143 if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)) && 1144 (pm->pm_flags & PMC_F_ATTACHED_TO_OWNER) == 0) 1145 pm->pm_flags |= PMC_F_NEEDS_LOGFILE; 1146 1147 pm->pm_flags |= PMC_F_ATTACH_DONE; /* mark as attached */ 1148 1149 /* issue an attach event to a configured log file */ 1150 if (pm->pm_owner->po_flags & PMC_PO_OWNS_LOGFILE) { 1151 if (p->p_flag & P_KPROC) { 1152 fullpath = kernelname; 1153 freepath = NULL; 1154 } else { 1155 pmc_getfilename(p->p_textvp, &fullpath, &freepath); 1156 pmclog_process_pmcattach(pm, p->p_pid, fullpath); 1157 } 1158 free(freepath, M_TEMP); 1159 if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm))) 1160 pmc_log_process_mappings(pm->pm_owner, p); 1161 } 1162 1163 return (0); 1164 fail: 1165 PROC_LOCK(p); 1166 p->p_flag &= ~P_HWPMC; 1167 PROC_UNLOCK(p); 1168 return (error); 1169 } 1170 1171 /* 1172 * Attach a process and optionally its children 1173 */ 1174 1175 static int 1176 pmc_attach_process(struct proc *p, struct pmc *pm) 1177 { 1178 int error; 1179 struct proc *top; 1180 1181 sx_assert(&pmc_sx, SX_XLOCKED); 1182 1183 PMCDBG5(PRC,ATT,1, "attach pm=%p ri=%d proc=%p (%d, %s)", pm, 1184 PMC_TO_ROWINDEX(pm), p, p->p_pid, p->p_comm); 1185 1186 1187 /* 1188 * If this PMC successfully allowed a GETMSR operation 1189 * in the past, disallow further ATTACHes. 1190 */ 1191 1192 if ((pm->pm_flags & PMC_PP_ENABLE_MSR_ACCESS) != 0) 1193 return EPERM; 1194 1195 if ((pm->pm_flags & PMC_F_DESCENDANTS) == 0) 1196 return pmc_attach_one_process(p, pm); 1197 1198 /* 1199 * Traverse all child processes, attaching them to 1200 * this PMC. 1201 */ 1202 1203 sx_slock(&proctree_lock); 1204 1205 top = p; 1206 1207 for (;;) { 1208 if ((error = pmc_attach_one_process(p, pm)) != 0) 1209 break; 1210 if (!LIST_EMPTY(&p->p_children)) 1211 p = LIST_FIRST(&p->p_children); 1212 else for (;;) { 1213 if (p == top) 1214 goto done; 1215 if (LIST_NEXT(p, p_sibling)) { 1216 p = LIST_NEXT(p, p_sibling); 1217 break; 1218 } 1219 p = p->p_pptr; 1220 } 1221 } 1222 1223 if (error) 1224 (void) pmc_detach_process(top, pm); 1225 1226 done: 1227 sx_sunlock(&proctree_lock); 1228 return error; 1229 } 1230 1231 /* 1232 * Detach a process from a PMC. If there are no other PMCs tracking 1233 * this process, remove the process structure from its hash table. If 1234 * 'flags' contains PMC_FLAG_REMOVE, then free the process structure. 1235 */ 1236 1237 static int 1238 pmc_detach_one_process(struct proc *p, struct pmc *pm, int flags) 1239 { 1240 int ri; 1241 struct pmc_process *pp; 1242 1243 sx_assert(&pmc_sx, SX_XLOCKED); 1244 1245 KASSERT(pm != NULL, 1246 ("[pmc,%d] null pm pointer", __LINE__)); 1247 1248 ri = PMC_TO_ROWINDEX(pm); 1249 1250 PMCDBG6(PRC,ATT,2, "detach-one pm=%p ri=%d proc=%p (%d, %s) flags=0x%x", 1251 pm, ri, p, p->p_pid, p->p_comm, flags); 1252 1253 if ((pp = pmc_find_process_descriptor(p, 0)) == NULL) 1254 return ESRCH; 1255 1256 if (pp->pp_pmcs[ri].pp_pmc != pm) 1257 return EINVAL; 1258 1259 pmc_unlink_target_process(pm, pp); 1260 1261 /* Issue a detach entry if a log file is configured */ 1262 if (pm->pm_owner->po_flags & PMC_PO_OWNS_LOGFILE) 1263 pmclog_process_pmcdetach(pm, p->p_pid); 1264 1265 /* 1266 * If there are no PMCs targeting this process, we remove its 1267 * descriptor from the target hash table and unset the P_HWPMC 1268 * flag in the struct proc. 1269 */ 1270 KASSERT(pp->pp_refcnt >= 0 && pp->pp_refcnt <= (int) md->pmd_npmc, 1271 ("[pmc,%d] Illegal refcnt %d for process struct %p", 1272 __LINE__, pp->pp_refcnt, pp)); 1273 1274 if (pp->pp_refcnt != 0) /* still a target of some PMC */ 1275 return 0; 1276 1277 pmc_remove_process_descriptor(pp); 1278 1279 if (flags & PMC_FLAG_REMOVE) 1280 pmc_destroy_process_descriptor(pp); 1281 1282 PROC_LOCK(p); 1283 p->p_flag &= ~P_HWPMC; 1284 PROC_UNLOCK(p); 1285 1286 return 0; 1287 } 1288 1289 /* 1290 * Detach a process and optionally its descendants from a PMC. 1291 */ 1292 1293 static int 1294 pmc_detach_process(struct proc *p, struct pmc *pm) 1295 { 1296 struct proc *top; 1297 1298 sx_assert(&pmc_sx, SX_XLOCKED); 1299 1300 PMCDBG5(PRC,ATT,1, "detach pm=%p ri=%d proc=%p (%d, %s)", pm, 1301 PMC_TO_ROWINDEX(pm), p, p->p_pid, p->p_comm); 1302 1303 if ((pm->pm_flags & PMC_F_DESCENDANTS) == 0) 1304 return pmc_detach_one_process(p, pm, PMC_FLAG_REMOVE); 1305 1306 /* 1307 * Traverse all children, detaching them from this PMC. We 1308 * ignore errors since we could be detaching a PMC from a 1309 * partially attached proc tree. 1310 */ 1311 1312 sx_slock(&proctree_lock); 1313 1314 top = p; 1315 1316 for (;;) { 1317 (void) pmc_detach_one_process(p, pm, PMC_FLAG_REMOVE); 1318 1319 if (!LIST_EMPTY(&p->p_children)) 1320 p = LIST_FIRST(&p->p_children); 1321 else for (;;) { 1322 if (p == top) 1323 goto done; 1324 if (LIST_NEXT(p, p_sibling)) { 1325 p = LIST_NEXT(p, p_sibling); 1326 break; 1327 } 1328 p = p->p_pptr; 1329 } 1330 } 1331 1332 done: 1333 sx_sunlock(&proctree_lock); 1334 1335 if (LIST_EMPTY(&pm->pm_targets)) 1336 pm->pm_flags &= ~PMC_F_ATTACH_DONE; 1337 1338 return 0; 1339 } 1340 1341 1342 /* 1343 * Thread context switch IN 1344 */ 1345 1346 static void 1347 pmc_process_csw_in(struct thread *td) 1348 { 1349 int cpu; 1350 unsigned int adjri, ri; 1351 struct pmc *pm; 1352 struct proc *p; 1353 struct pmc_cpu *pc; 1354 struct pmc_hw *phw; 1355 pmc_value_t newvalue; 1356 struct pmc_process *pp; 1357 struct pmc_thread *pt; 1358 struct pmc_classdep *pcd; 1359 1360 p = td->td_proc; 1361 pt = NULL; 1362 if ((pp = pmc_find_process_descriptor(p, PMC_FLAG_NONE)) == NULL) 1363 return; 1364 1365 KASSERT(pp->pp_proc == td->td_proc, 1366 ("[pmc,%d] not my thread state", __LINE__)); 1367 1368 critical_enter(); /* no preemption from this point */ 1369 1370 cpu = PCPU_GET(cpuid); /* td->td_oncpu is invalid */ 1371 1372 PMCDBG5(CSW,SWI,1, "cpu=%d proc=%p (%d, %s) pp=%p", cpu, p, 1373 p->p_pid, p->p_comm, pp); 1374 1375 KASSERT(cpu >= 0 && cpu < pmc_cpu_max(), 1376 ("[pmc,%d] weird CPU id %d", __LINE__, cpu)); 1377 1378 pc = pmc_pcpu[cpu]; 1379 1380 for (ri = 0; ri < md->pmd_npmc; ri++) { 1381 1382 if ((pm = pp->pp_pmcs[ri].pp_pmc) == NULL) 1383 continue; 1384 1385 KASSERT(PMC_IS_VIRTUAL_MODE(PMC_TO_MODE(pm)), 1386 ("[pmc,%d] Target PMC in non-virtual mode (%d)", 1387 __LINE__, PMC_TO_MODE(pm))); 1388 1389 KASSERT(PMC_TO_ROWINDEX(pm) == ri, 1390 ("[pmc,%d] Row index mismatch pmc %d != ri %d", 1391 __LINE__, PMC_TO_ROWINDEX(pm), ri)); 1392 1393 /* 1394 * Only PMCs that are marked as 'RUNNING' need 1395 * be placed on hardware. 1396 */ 1397 1398 if (pm->pm_state != PMC_STATE_RUNNING) 1399 continue; 1400 1401 /* increment PMC runcount */ 1402 counter_u64_add(pm->pm_runcount, 1); 1403 1404 /* configure the HWPMC we are going to use. */ 1405 pcd = pmc_ri_to_classdep(md, ri, &adjri); 1406 pcd->pcd_config_pmc(cpu, adjri, pm); 1407 1408 phw = pc->pc_hwpmcs[ri]; 1409 1410 KASSERT(phw != NULL, 1411 ("[pmc,%d] null hw pointer", __LINE__)); 1412 1413 KASSERT(phw->phw_pmc == pm, 1414 ("[pmc,%d] hw->pmc %p != pmc %p", __LINE__, 1415 phw->phw_pmc, pm)); 1416 1417 /* 1418 * Write out saved value and start the PMC. 1419 * 1420 * Sampling PMCs use a per-thread value, while 1421 * counting mode PMCs use a per-pmc value that is 1422 * inherited across descendants. 1423 */ 1424 if (PMC_TO_MODE(pm) == PMC_MODE_TS) { 1425 if (pt == NULL) 1426 pt = pmc_find_thread_descriptor(pp, td, 1427 PMC_FLAG_NONE); 1428 1429 KASSERT(pt != NULL, 1430 ("[pmc,%d] No thread found for td=%p", __LINE__, 1431 td)); 1432 1433 mtx_pool_lock_spin(pmc_mtxpool, pm); 1434 1435 /* 1436 * If we have a thread descriptor, use the per-thread 1437 * counter in the descriptor. If not, we will use 1438 * a per-process counter. 1439 * 1440 * TODO: Remove the per-process "safety net" once 1441 * we have thoroughly tested that we don't hit the 1442 * above assert. 1443 */ 1444 if (pt != NULL) { 1445 if (pt->pt_pmcs[ri].pt_pmcval > 0) 1446 newvalue = pt->pt_pmcs[ri].pt_pmcval; 1447 else 1448 newvalue = pm->pm_sc.pm_reloadcount; 1449 } else { 1450 /* 1451 * Use the saved value calculated after the most 1452 * recent time a thread using the shared counter 1453 * switched out. Reset the saved count in case 1454 * another thread from this process switches in 1455 * before any threads switch out. 1456 */ 1457 1458 newvalue = pp->pp_pmcs[ri].pp_pmcval; 1459 pp->pp_pmcs[ri].pp_pmcval = 1460 pm->pm_sc.pm_reloadcount; 1461 } 1462 mtx_pool_unlock_spin(pmc_mtxpool, pm); 1463 KASSERT(newvalue > 0 && newvalue <= 1464 pm->pm_sc.pm_reloadcount, 1465 ("[pmc,%d] pmcval outside of expected range cpu=%d " 1466 "ri=%d pmcval=%jx pm_reloadcount=%jx", __LINE__, 1467 cpu, ri, newvalue, pm->pm_sc.pm_reloadcount)); 1468 } else { 1469 KASSERT(PMC_TO_MODE(pm) == PMC_MODE_TC, 1470 ("[pmc,%d] illegal mode=%d", __LINE__, 1471 PMC_TO_MODE(pm))); 1472 mtx_pool_lock_spin(pmc_mtxpool, pm); 1473 newvalue = PMC_PCPU_SAVED(cpu, ri) = 1474 pm->pm_gv.pm_savedvalue; 1475 mtx_pool_unlock_spin(pmc_mtxpool, pm); 1476 } 1477 1478 PMCDBG3(CSW,SWI,1,"cpu=%d ri=%d new=%jd", cpu, ri, newvalue); 1479 1480 pcd->pcd_write_pmc(cpu, adjri, newvalue); 1481 1482 /* If a sampling mode PMC, reset stalled state. */ 1483 if (PMC_TO_MODE(pm) == PMC_MODE_TS) 1484 pm->pm_pcpu_state[cpu].pps_stalled = 0; 1485 1486 /* Indicate that we desire this to run. */ 1487 pm->pm_pcpu_state[cpu].pps_cpustate = 1; 1488 1489 /* Start the PMC. */ 1490 pcd->pcd_start_pmc(cpu, adjri); 1491 } 1492 1493 /* 1494 * perform any other architecture/cpu dependent thread 1495 * switch-in actions. 1496 */ 1497 1498 (void) (*md->pmd_switch_in)(pc, pp); 1499 1500 critical_exit(); 1501 1502 } 1503 1504 /* 1505 * Thread context switch OUT. 1506 */ 1507 1508 static void 1509 pmc_process_csw_out(struct thread *td) 1510 { 1511 int cpu; 1512 int64_t tmp; 1513 struct pmc *pm; 1514 struct proc *p; 1515 enum pmc_mode mode; 1516 struct pmc_cpu *pc; 1517 pmc_value_t newvalue; 1518 unsigned int adjri, ri; 1519 struct pmc_process *pp; 1520 struct pmc_thread *pt = NULL; 1521 struct pmc_classdep *pcd; 1522 1523 1524 /* 1525 * Locate our process descriptor; this may be NULL if 1526 * this process is exiting and we have already removed 1527 * the process from the target process table. 1528 * 1529 * Note that due to kernel preemption, multiple 1530 * context switches may happen while the process is 1531 * exiting. 1532 * 1533 * Note also that if the target process cannot be 1534 * found we still need to deconfigure any PMCs that 1535 * are currently running on hardware. 1536 */ 1537 1538 p = td->td_proc; 1539 pp = pmc_find_process_descriptor(p, PMC_FLAG_NONE); 1540 1541 /* 1542 * save PMCs 1543 */ 1544 1545 critical_enter(); 1546 1547 cpu = PCPU_GET(cpuid); /* td->td_oncpu is invalid */ 1548 1549 PMCDBG5(CSW,SWO,1, "cpu=%d proc=%p (%d, %s) pp=%p", cpu, p, 1550 p->p_pid, p->p_comm, pp); 1551 1552 KASSERT(cpu >= 0 && cpu < pmc_cpu_max(), 1553 ("[pmc,%d weird CPU id %d", __LINE__, cpu)); 1554 1555 pc = pmc_pcpu[cpu]; 1556 1557 /* 1558 * When a PMC gets unlinked from a target PMC, it will 1559 * be removed from the target's pp_pmc[] array. 1560 * 1561 * However, on a MP system, the target could have been 1562 * executing on another CPU at the time of the unlink. 1563 * So, at context switch OUT time, we need to look at 1564 * the hardware to determine if a PMC is scheduled on 1565 * it. 1566 */ 1567 1568 for (ri = 0; ri < md->pmd_npmc; ri++) { 1569 1570 pcd = pmc_ri_to_classdep(md, ri, &adjri); 1571 pm = NULL; 1572 (void) (*pcd->pcd_get_config)(cpu, adjri, &pm); 1573 1574 if (pm == NULL) /* nothing at this row index */ 1575 continue; 1576 1577 mode = PMC_TO_MODE(pm); 1578 if (!PMC_IS_VIRTUAL_MODE(mode)) 1579 continue; /* not a process virtual PMC */ 1580 1581 KASSERT(PMC_TO_ROWINDEX(pm) == ri, 1582 ("[pmc,%d] ri mismatch pmc(%d) ri(%d)", 1583 __LINE__, PMC_TO_ROWINDEX(pm), ri)); 1584 1585 /* 1586 * Change desired state, and then stop if not stalled. 1587 * This two-step dance should avoid race conditions where 1588 * an interrupt re-enables the PMC after this code has 1589 * already checked the pm_stalled flag. 1590 */ 1591 pm->pm_pcpu_state[cpu].pps_cpustate = 0; 1592 if (pm->pm_pcpu_state[cpu].pps_stalled == 0) 1593 pcd->pcd_stop_pmc(cpu, adjri); 1594 1595 /* reduce this PMC's runcount */ 1596 counter_u64_add(pm->pm_runcount, -1); 1597 1598 /* 1599 * If this PMC is associated with this process, 1600 * save the reading. 1601 */ 1602 1603 if (pm->pm_state != PMC_STATE_DELETED && pp != NULL && 1604 pp->pp_pmcs[ri].pp_pmc != NULL) { 1605 KASSERT(pm == pp->pp_pmcs[ri].pp_pmc, 1606 ("[pmc,%d] pm %p != pp_pmcs[%d] %p", __LINE__, 1607 pm, ri, pp->pp_pmcs[ri].pp_pmc)); 1608 1609 KASSERT(pp->pp_refcnt > 0, 1610 ("[pmc,%d] pp refcnt = %d", __LINE__, 1611 pp->pp_refcnt)); 1612 1613 pcd->pcd_read_pmc(cpu, adjri, &newvalue); 1614 1615 if (mode == PMC_MODE_TS) { 1616 PMCDBG3(CSW,SWO,1,"cpu=%d ri=%d val=%jd (samp)", 1617 cpu, ri, newvalue); 1618 1619 if (pt == NULL) 1620 pt = pmc_find_thread_descriptor(pp, td, 1621 PMC_FLAG_NONE); 1622 1623 KASSERT(pt != NULL, 1624 ("[pmc,%d] No thread found for td=%p", 1625 __LINE__, td)); 1626 1627 mtx_pool_lock_spin(pmc_mtxpool, pm); 1628 1629 /* 1630 * If we have a thread descriptor, save the 1631 * per-thread counter in the descriptor. If not, 1632 * we will update the per-process counter. 1633 * 1634 * TODO: Remove the per-process "safety net" 1635 * once we have thoroughly tested that we 1636 * don't hit the above assert. 1637 */ 1638 if (pt != NULL) 1639 pt->pt_pmcs[ri].pt_pmcval = newvalue; 1640 else { 1641 /* 1642 * For sampling process-virtual PMCs, 1643 * newvalue is the number of events to 1644 * be seen until the next sampling 1645 * interrupt. We can just add the events 1646 * left from this invocation to the 1647 * counter, then adjust in case we 1648 * overflow our range. 1649 * 1650 * (Recall that we reload the counter 1651 * every time we use it.) 1652 */ 1653 pp->pp_pmcs[ri].pp_pmcval += newvalue; 1654 if (pp->pp_pmcs[ri].pp_pmcval > 1655 pm->pm_sc.pm_reloadcount) 1656 pp->pp_pmcs[ri].pp_pmcval -= 1657 pm->pm_sc.pm_reloadcount; 1658 } 1659 mtx_pool_unlock_spin(pmc_mtxpool, pm); 1660 } else { 1661 tmp = newvalue - PMC_PCPU_SAVED(cpu,ri); 1662 1663 PMCDBG3(CSW,SWO,1,"cpu=%d ri=%d tmp=%jd (count)", 1664 cpu, ri, tmp); 1665 1666 /* 1667 * For counting process-virtual PMCs, 1668 * we expect the count to be 1669 * increasing monotonically, modulo a 64 1670 * bit wraparound. 1671 */ 1672 KASSERT(tmp >= 0, 1673 ("[pmc,%d] negative increment cpu=%d " 1674 "ri=%d newvalue=%jx saved=%jx " 1675 "incr=%jx", __LINE__, cpu, ri, 1676 newvalue, PMC_PCPU_SAVED(cpu,ri), tmp)); 1677 1678 mtx_pool_lock_spin(pmc_mtxpool, pm); 1679 pm->pm_gv.pm_savedvalue += tmp; 1680 pp->pp_pmcs[ri].pp_pmcval += tmp; 1681 mtx_pool_unlock_spin(pmc_mtxpool, pm); 1682 1683 if (pm->pm_flags & PMC_F_LOG_PROCCSW) 1684 pmclog_process_proccsw(pm, pp, tmp, td); 1685 } 1686 } 1687 1688 /* mark hardware as free */ 1689 pcd->pcd_config_pmc(cpu, adjri, NULL); 1690 } 1691 1692 /* 1693 * perform any other architecture/cpu dependent thread 1694 * switch out functions. 1695 */ 1696 1697 (void) (*md->pmd_switch_out)(pc, pp); 1698 1699 critical_exit(); 1700 } 1701 1702 /* 1703 * A new thread for a process. 1704 */ 1705 static void 1706 pmc_process_thread_add(struct thread *td) 1707 { 1708 struct pmc_process *pmc; 1709 1710 pmc = pmc_find_process_descriptor(td->td_proc, PMC_FLAG_NONE); 1711 if (pmc != NULL) 1712 pmc_find_thread_descriptor(pmc, td, PMC_FLAG_ALLOCATE); 1713 } 1714 1715 /* 1716 * A thread delete for a process. 1717 */ 1718 static void 1719 pmc_process_thread_delete(struct thread *td) 1720 { 1721 struct pmc_process *pmc; 1722 1723 pmc = pmc_find_process_descriptor(td->td_proc, PMC_FLAG_NONE); 1724 if (pmc != NULL) 1725 pmc_thread_descriptor_pool_free(pmc_find_thread_descriptor(pmc, 1726 td, PMC_FLAG_REMOVE)); 1727 } 1728 1729 /* 1730 * A userret() call for a thread. 1731 */ 1732 static void 1733 pmc_process_thread_userret(struct thread *td) 1734 { 1735 sched_pin(); 1736 pmc_capture_user_callchain(curcpu, PMC_UR, td->td_frame); 1737 sched_unpin(); 1738 } 1739 1740 /* 1741 * A mapping change for a process. 1742 */ 1743 1744 static void 1745 pmc_process_mmap(struct thread *td, struct pmckern_map_in *pkm) 1746 { 1747 int ri; 1748 pid_t pid; 1749 char *fullpath, *freepath; 1750 const struct pmc *pm; 1751 struct pmc_owner *po; 1752 const struct pmc_process *pp; 1753 1754 freepath = fullpath = NULL; 1755 MPASS(!in_epoch()); 1756 pmc_getfilename((struct vnode *) pkm->pm_file, &fullpath, &freepath); 1757 1758 pid = td->td_proc->p_pid; 1759 1760 epoch_enter_preempt(global_epoch_preempt); 1761 /* Inform owners of all system-wide sampling PMCs. */ 1762 CK_LIST_FOREACH(po, &pmc_ss_owners, po_ssnext) 1763 if (po->po_flags & PMC_PO_OWNS_LOGFILE) 1764 pmclog_process_map_in(po, pid, pkm->pm_address, fullpath); 1765 1766 if ((pp = pmc_find_process_descriptor(td->td_proc, 0)) == NULL) 1767 goto done; 1768 1769 /* 1770 * Inform sampling PMC owners tracking this process. 1771 */ 1772 for (ri = 0; ri < md->pmd_npmc; ri++) 1773 if ((pm = pp->pp_pmcs[ri].pp_pmc) != NULL && 1774 PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm))) 1775 pmclog_process_map_in(pm->pm_owner, 1776 pid, pkm->pm_address, fullpath); 1777 1778 done: 1779 if (freepath) 1780 free(freepath, M_TEMP); 1781 epoch_exit_preempt(global_epoch_preempt); 1782 } 1783 1784 1785 /* 1786 * Log an munmap request. 1787 */ 1788 1789 static void 1790 pmc_process_munmap(struct thread *td, struct pmckern_map_out *pkm) 1791 { 1792 int ri; 1793 pid_t pid; 1794 struct pmc_owner *po; 1795 const struct pmc *pm; 1796 const struct pmc_process *pp; 1797 1798 pid = td->td_proc->p_pid; 1799 1800 epoch_enter_preempt(global_epoch_preempt); 1801 CK_LIST_FOREACH(po, &pmc_ss_owners, po_ssnext) 1802 if (po->po_flags & PMC_PO_OWNS_LOGFILE) 1803 pmclog_process_map_out(po, pid, pkm->pm_address, 1804 pkm->pm_address + pkm->pm_size); 1805 epoch_exit_preempt(global_epoch_preempt); 1806 1807 if ((pp = pmc_find_process_descriptor(td->td_proc, 0)) == NULL) 1808 return; 1809 1810 for (ri = 0; ri < md->pmd_npmc; ri++) 1811 if ((pm = pp->pp_pmcs[ri].pp_pmc) != NULL && 1812 PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm))) 1813 pmclog_process_map_out(pm->pm_owner, pid, 1814 pkm->pm_address, pkm->pm_address + pkm->pm_size); 1815 } 1816 1817 /* 1818 * Log mapping information about the kernel. 1819 */ 1820 1821 static void 1822 pmc_log_kernel_mappings(struct pmc *pm) 1823 { 1824 struct pmc_owner *po; 1825 struct pmckern_map_in *km, *kmbase; 1826 1827 MPASS(in_epoch() || sx_xlocked(&pmc_sx)); 1828 KASSERT(PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)), 1829 ("[pmc,%d] non-sampling PMC (%p) desires mapping information", 1830 __LINE__, (void *) pm)); 1831 1832 po = pm->pm_owner; 1833 1834 if (po->po_flags & PMC_PO_INITIAL_MAPPINGS_DONE) 1835 return; 1836 if (PMC_TO_MODE(pm) == PMC_MODE_SS) 1837 pmc_process_allproc(pm); 1838 /* 1839 * Log the current set of kernel modules. 1840 */ 1841 kmbase = linker_hwpmc_list_objects(); 1842 for (km = kmbase; km->pm_file != NULL; km++) { 1843 PMCDBG2(LOG,REG,1,"%s %p", (char *) km->pm_file, 1844 (void *) km->pm_address); 1845 pmclog_process_map_in(po, (pid_t) -1, km->pm_address, 1846 km->pm_file); 1847 } 1848 free(kmbase, M_LINKER); 1849 1850 po->po_flags |= PMC_PO_INITIAL_MAPPINGS_DONE; 1851 } 1852 1853 /* 1854 * Log the mappings for a single process. 1855 */ 1856 1857 static void 1858 pmc_log_process_mappings(struct pmc_owner *po, struct proc *p) 1859 { 1860 vm_map_t map; 1861 struct vnode *vp; 1862 struct vmspace *vm; 1863 vm_map_entry_t entry; 1864 vm_offset_t last_end; 1865 u_int last_timestamp; 1866 struct vnode *last_vp; 1867 vm_offset_t start_addr; 1868 vm_object_t obj, lobj, tobj; 1869 char *fullpath, *freepath; 1870 1871 last_vp = NULL; 1872 last_end = (vm_offset_t) 0; 1873 fullpath = freepath = NULL; 1874 1875 if ((vm = vmspace_acquire_ref(p)) == NULL) 1876 return; 1877 1878 map = &vm->vm_map; 1879 vm_map_lock_read(map); 1880 1881 for (entry = map->header.next; entry != &map->header; entry = entry->next) { 1882 1883 if (entry == NULL) { 1884 PMCDBG2(LOG,OPS,2, "hwpmc: vm_map entry unexpectedly " 1885 "NULL! pid=%d vm_map=%p\n", p->p_pid, map); 1886 break; 1887 } 1888 1889 /* 1890 * We only care about executable map entries. 1891 */ 1892 if ((entry->eflags & MAP_ENTRY_IS_SUB_MAP) || 1893 !(entry->protection & VM_PROT_EXECUTE) || 1894 (entry->object.vm_object == NULL)) { 1895 continue; 1896 } 1897 1898 obj = entry->object.vm_object; 1899 VM_OBJECT_RLOCK(obj); 1900 1901 /* 1902 * Walk the backing_object list to find the base 1903 * (non-shadowed) vm_object. 1904 */ 1905 for (lobj = tobj = obj; tobj != NULL; tobj = tobj->backing_object) { 1906 if (tobj != obj) 1907 VM_OBJECT_RLOCK(tobj); 1908 if (lobj != obj) 1909 VM_OBJECT_RUNLOCK(lobj); 1910 lobj = tobj; 1911 } 1912 1913 /* 1914 * At this point lobj is the base vm_object and it is locked. 1915 */ 1916 if (lobj == NULL) { 1917 PMCDBG3(LOG,OPS,2, "hwpmc: lobj unexpectedly NULL! pid=%d " 1918 "vm_map=%p vm_obj=%p\n", p->p_pid, map, obj); 1919 VM_OBJECT_RUNLOCK(obj); 1920 continue; 1921 } 1922 1923 vp = vm_object_vnode(lobj); 1924 if (vp == NULL) { 1925 if (lobj != obj) 1926 VM_OBJECT_RUNLOCK(lobj); 1927 VM_OBJECT_RUNLOCK(obj); 1928 continue; 1929 } 1930 1931 /* 1932 * Skip contiguous regions that point to the same 1933 * vnode, so we don't emit redundant MAP-IN 1934 * directives. 1935 */ 1936 if (entry->start == last_end && vp == last_vp) { 1937 last_end = entry->end; 1938 if (lobj != obj) 1939 VM_OBJECT_RUNLOCK(lobj); 1940 VM_OBJECT_RUNLOCK(obj); 1941 continue; 1942 } 1943 1944 /* 1945 * We don't want to keep the proc's vm_map or this 1946 * vm_object locked while we walk the pathname, since 1947 * vn_fullpath() can sleep. However, if we drop the 1948 * lock, it's possible for concurrent activity to 1949 * modify the vm_map list. To protect against this, 1950 * we save the vm_map timestamp before we release the 1951 * lock, and check it after we reacquire the lock 1952 * below. 1953 */ 1954 start_addr = entry->start; 1955 last_end = entry->end; 1956 last_timestamp = map->timestamp; 1957 vm_map_unlock_read(map); 1958 1959 vref(vp); 1960 if (lobj != obj) 1961 VM_OBJECT_RUNLOCK(lobj); 1962 1963 VM_OBJECT_RUNLOCK(obj); 1964 1965 freepath = NULL; 1966 pmc_getfilename(vp, &fullpath, &freepath); 1967 last_vp = vp; 1968 1969 vrele(vp); 1970 1971 vp = NULL; 1972 pmclog_process_map_in(po, p->p_pid, start_addr, fullpath); 1973 if (freepath) 1974 free(freepath, M_TEMP); 1975 1976 vm_map_lock_read(map); 1977 1978 /* 1979 * If our saved timestamp doesn't match, this means 1980 * that the vm_map was modified out from under us and 1981 * we can't trust our current "entry" pointer. Do a 1982 * new lookup for this entry. If there is no entry 1983 * for this address range, vm_map_lookup_entry() will 1984 * return the previous one, so we always want to go to 1985 * entry->next on the next loop iteration. 1986 * 1987 * There is an edge condition here that can occur if 1988 * there is no entry at or before this address. In 1989 * this situation, vm_map_lookup_entry returns 1990 * &map->header, which would cause our loop to abort 1991 * without processing the rest of the map. However, 1992 * in practice this will never happen for process 1993 * vm_map. This is because the executable's text 1994 * segment is the first mapping in the proc's address 1995 * space, and this mapping is never removed until the 1996 * process exits, so there will always be a non-header 1997 * entry at or before the requested address for 1998 * vm_map_lookup_entry to return. 1999 */ 2000 if (map->timestamp != last_timestamp) 2001 vm_map_lookup_entry(map, last_end - 1, &entry); 2002 } 2003 2004 vm_map_unlock_read(map); 2005 vmspace_free(vm); 2006 return; 2007 } 2008 2009 /* 2010 * Log mappings for all processes in the system. 2011 */ 2012 2013 static void 2014 pmc_log_all_process_mappings(struct pmc_owner *po) 2015 { 2016 struct proc *p, *top; 2017 2018 sx_assert(&pmc_sx, SX_XLOCKED); 2019 2020 if ((p = pfind(1)) == NULL) 2021 panic("[pmc,%d] Cannot find init", __LINE__); 2022 2023 PROC_UNLOCK(p); 2024 2025 sx_slock(&proctree_lock); 2026 2027 top = p; 2028 2029 for (;;) { 2030 pmc_log_process_mappings(po, p); 2031 if (!LIST_EMPTY(&p->p_children)) 2032 p = LIST_FIRST(&p->p_children); 2033 else for (;;) { 2034 if (p == top) 2035 goto done; 2036 if (LIST_NEXT(p, p_sibling)) { 2037 p = LIST_NEXT(p, p_sibling); 2038 break; 2039 } 2040 p = p->p_pptr; 2041 } 2042 } 2043 done: 2044 sx_sunlock(&proctree_lock); 2045 } 2046 2047 /* 2048 * The 'hook' invoked from the kernel proper 2049 */ 2050 2051 2052 #ifdef HWPMC_DEBUG 2053 const char *pmc_hooknames[] = { 2054 /* these strings correspond to PMC_FN_* in <sys/pmckern.h> */ 2055 "", 2056 "EXEC", 2057 "CSW-IN", 2058 "CSW-OUT", 2059 "SAMPLE", 2060 "UNUSED1", 2061 "UNUSED2", 2062 "MMAP", 2063 "MUNMAP", 2064 "CALLCHAIN-NMI", 2065 "CALLCHAIN-SOFT", 2066 "SOFTSAMPLING", 2067 "THR-CREATE", 2068 "THR-EXIT", 2069 "THR-USERRET", 2070 "THR-CREATE-LOG", 2071 "THR-EXIT-LOG", 2072 "PROC-CREATE-LOG" 2073 }; 2074 #endif 2075 2076 static int 2077 pmc_hook_handler(struct thread *td, int function, void *arg) 2078 { 2079 int cpu; 2080 2081 PMCDBG4(MOD,PMH,1, "hook td=%p func=%d \"%s\" arg=%p", td, function, 2082 pmc_hooknames[function], arg); 2083 2084 switch (function) 2085 { 2086 2087 /* 2088 * Process exec() 2089 */ 2090 2091 case PMC_FN_PROCESS_EXEC: 2092 { 2093 char *fullpath, *freepath; 2094 unsigned int ri; 2095 int is_using_hwpmcs; 2096 struct pmc *pm; 2097 struct proc *p; 2098 struct pmc_owner *po; 2099 struct pmc_process *pp; 2100 struct pmckern_procexec *pk; 2101 2102 sx_assert(&pmc_sx, SX_XLOCKED); 2103 2104 p = td->td_proc; 2105 pmc_getfilename(p->p_textvp, &fullpath, &freepath); 2106 2107 pk = (struct pmckern_procexec *) arg; 2108 2109 epoch_enter_preempt(global_epoch_preempt); 2110 /* Inform owners of SS mode PMCs of the exec event. */ 2111 CK_LIST_FOREACH(po, &pmc_ss_owners, po_ssnext) 2112 if (po->po_flags & PMC_PO_OWNS_LOGFILE) 2113 pmclog_process_procexec(po, PMC_ID_INVALID, 2114 p->p_pid, pk->pm_entryaddr, fullpath); 2115 epoch_exit_preempt(global_epoch_preempt); 2116 2117 PROC_LOCK(p); 2118 is_using_hwpmcs = p->p_flag & P_HWPMC; 2119 PROC_UNLOCK(p); 2120 2121 if (!is_using_hwpmcs) { 2122 if (freepath) 2123 free(freepath, M_TEMP); 2124 break; 2125 } 2126 2127 /* 2128 * PMCs are not inherited across an exec(): remove any 2129 * PMCs that this process is the owner of. 2130 */ 2131 2132 if ((po = pmc_find_owner_descriptor(p)) != NULL) { 2133 pmc_remove_owner(po); 2134 pmc_destroy_owner_descriptor(po); 2135 } 2136 2137 /* 2138 * If the process being exec'ed is not the target of any 2139 * PMC, we are done. 2140 */ 2141 if ((pp = pmc_find_process_descriptor(p, 0)) == NULL) { 2142 if (freepath) 2143 free(freepath, M_TEMP); 2144 break; 2145 } 2146 2147 /* 2148 * Log the exec event to all monitoring owners. Skip 2149 * owners who have already received the event because 2150 * they had system sampling PMCs active. 2151 */ 2152 for (ri = 0; ri < md->pmd_npmc; ri++) 2153 if ((pm = pp->pp_pmcs[ri].pp_pmc) != NULL) { 2154 po = pm->pm_owner; 2155 if (po->po_sscount == 0 && 2156 po->po_flags & PMC_PO_OWNS_LOGFILE) 2157 pmclog_process_procexec(po, pm->pm_id, 2158 p->p_pid, pk->pm_entryaddr, 2159 fullpath); 2160 } 2161 2162 if (freepath) 2163 free(freepath, M_TEMP); 2164 2165 2166 PMCDBG4(PRC,EXC,1, "exec proc=%p (%d, %s) cred-changed=%d", 2167 p, p->p_pid, p->p_comm, pk->pm_credentialschanged); 2168 2169 if (pk->pm_credentialschanged == 0) /* no change */ 2170 break; 2171 2172 /* 2173 * If the newly exec()'ed process has a different credential 2174 * than before, allow it to be the target of a PMC only if 2175 * the PMC's owner has sufficient privilege. 2176 */ 2177 2178 for (ri = 0; ri < md->pmd_npmc; ri++) 2179 if ((pm = pp->pp_pmcs[ri].pp_pmc) != NULL) 2180 if (pmc_can_attach(pm, td->td_proc) != 0) 2181 pmc_detach_one_process(td->td_proc, 2182 pm, PMC_FLAG_NONE); 2183 2184 KASSERT(pp->pp_refcnt >= 0 && pp->pp_refcnt <= (int) md->pmd_npmc, 2185 ("[pmc,%d] Illegal ref count %d on pp %p", __LINE__, 2186 pp->pp_refcnt, pp)); 2187 2188 /* 2189 * If this process is no longer the target of any 2190 * PMCs, we can remove the process entry and free 2191 * up space. 2192 */ 2193 2194 if (pp->pp_refcnt == 0) { 2195 pmc_remove_process_descriptor(pp); 2196 pmc_destroy_process_descriptor(pp); 2197 break; 2198 } 2199 2200 } 2201 break; 2202 2203 case PMC_FN_CSW_IN: 2204 pmc_process_csw_in(td); 2205 break; 2206 2207 case PMC_FN_CSW_OUT: 2208 pmc_process_csw_out(td); 2209 break; 2210 2211 /* 2212 * Process accumulated PC samples. 2213 * 2214 * This function is expected to be called by hardclock() for 2215 * each CPU that has accumulated PC samples. 2216 * 2217 * This function is to be executed on the CPU whose samples 2218 * are being processed. 2219 */ 2220 case PMC_FN_DO_SAMPLES: 2221 2222 /* 2223 * Clear the cpu specific bit in the CPU mask before 2224 * do the rest of the processing. If the NMI handler 2225 * gets invoked after the "atomic_clear_int()" call 2226 * below but before "pmc_process_samples()" gets 2227 * around to processing the interrupt, then we will 2228 * come back here at the next hardclock() tick (and 2229 * may find nothing to do if "pmc_process_samples()" 2230 * had already processed the interrupt). We don't 2231 * lose the interrupt sample. 2232 */ 2233 DPCPU_SET(pmc_sampled, 0); 2234 cpu = PCPU_GET(cpuid); 2235 pmc_process_samples(cpu, PMC_HR); 2236 pmc_process_samples(cpu, PMC_SR); 2237 pmc_process_samples(cpu, PMC_UR); 2238 break; 2239 2240 case PMC_FN_MMAP: 2241 pmc_process_mmap(td, (struct pmckern_map_in *) arg); 2242 break; 2243 2244 case PMC_FN_MUNMAP: 2245 MPASS(in_epoch() || sx_xlocked(&pmc_sx)); 2246 pmc_process_munmap(td, (struct pmckern_map_out *) arg); 2247 break; 2248 2249 case PMC_FN_PROC_CREATE_LOG: 2250 pmc_process_proccreate((struct proc *)arg); 2251 break; 2252 2253 case PMC_FN_USER_CALLCHAIN: 2254 /* 2255 * Record a call chain. 2256 */ 2257 KASSERT(td == curthread, ("[pmc,%d] td != curthread", 2258 __LINE__)); 2259 2260 pmc_capture_user_callchain(PCPU_GET(cpuid), PMC_HR, 2261 (struct trapframe *) arg); 2262 2263 KASSERT(td->td_pinned == 1, 2264 ("[pmc,%d] invalid td_pinned value", __LINE__)); 2265 sched_unpin(); /* Can migrate safely now. */ 2266 2267 td->td_pflags &= ~TDP_CALLCHAIN; 2268 break; 2269 2270 case PMC_FN_USER_CALLCHAIN_SOFT: 2271 /* 2272 * Record a call chain. 2273 */ 2274 KASSERT(td == curthread, ("[pmc,%d] td != curthread", 2275 __LINE__)); 2276 2277 cpu = PCPU_GET(cpuid); 2278 pmc_capture_user_callchain(cpu, PMC_SR, 2279 (struct trapframe *) arg); 2280 2281 KASSERT(td->td_pinned == 1, 2282 ("[pmc,%d] invalid td_pinned value", __LINE__)); 2283 2284 sched_unpin(); /* Can migrate safely now. */ 2285 2286 td->td_pflags &= ~TDP_CALLCHAIN; 2287 break; 2288 2289 case PMC_FN_SOFT_SAMPLING: 2290 /* 2291 * Call soft PMC sampling intr. 2292 */ 2293 pmc_soft_intr((struct pmckern_soft *) arg); 2294 break; 2295 2296 case PMC_FN_THR_CREATE: 2297 pmc_process_thread_add(td); 2298 pmc_process_threadcreate(td); 2299 break; 2300 2301 case PMC_FN_THR_CREATE_LOG: 2302 pmc_process_threadcreate(td); 2303 break; 2304 2305 case PMC_FN_THR_EXIT: 2306 KASSERT(td == curthread, ("[pmc,%d] td != curthread", 2307 __LINE__)); 2308 pmc_process_thread_delete(td); 2309 pmc_process_threadexit(td); 2310 break; 2311 case PMC_FN_THR_EXIT_LOG: 2312 pmc_process_threadexit(td); 2313 break; 2314 case PMC_FN_THR_USERRET: 2315 KASSERT(td == curthread, ("[pmc,%d] td != curthread", 2316 __LINE__)); 2317 pmc_process_thread_userret(td); 2318 break; 2319 2320 default: 2321 #ifdef HWPMC_DEBUG 2322 KASSERT(0, ("[pmc,%d] unknown hook %d\n", __LINE__, function)); 2323 #endif 2324 break; 2325 2326 } 2327 2328 return 0; 2329 } 2330 2331 /* 2332 * allocate a 'struct pmc_owner' descriptor in the owner hash table. 2333 */ 2334 2335 static struct pmc_owner * 2336 pmc_allocate_owner_descriptor(struct proc *p) 2337 { 2338 uint32_t hindex; 2339 struct pmc_owner *po; 2340 struct pmc_ownerhash *poh; 2341 2342 hindex = PMC_HASH_PTR(p, pmc_ownerhashmask); 2343 poh = &pmc_ownerhash[hindex]; 2344 2345 /* allocate space for N pointers and one descriptor struct */ 2346 po = malloc(sizeof(struct pmc_owner), M_PMC, M_WAITOK|M_ZERO); 2347 po->po_owner = p; 2348 LIST_INSERT_HEAD(poh, po, po_next); /* insert into hash table */ 2349 2350 TAILQ_INIT(&po->po_logbuffers); 2351 mtx_init(&po->po_mtx, "pmc-owner-mtx", "pmc-per-proc", MTX_SPIN); 2352 2353 PMCDBG4(OWN,ALL,1, "allocate-owner proc=%p (%d, %s) pmc-owner=%p", 2354 p, p->p_pid, p->p_comm, po); 2355 2356 return po; 2357 } 2358 2359 static void 2360 pmc_destroy_owner_descriptor(struct pmc_owner *po) 2361 { 2362 2363 PMCDBG4(OWN,REL,1, "destroy-owner po=%p proc=%p (%d, %s)", 2364 po, po->po_owner, po->po_owner->p_pid, po->po_owner->p_comm); 2365 2366 mtx_destroy(&po->po_mtx); 2367 free(po, M_PMC); 2368 } 2369 2370 /* 2371 * Allocate a thread descriptor from the free pool. 2372 * 2373 * NOTE: This *can* return NULL. 2374 */ 2375 static struct pmc_thread * 2376 pmc_thread_descriptor_pool_alloc(void) 2377 { 2378 struct pmc_thread *pt; 2379 2380 mtx_lock_spin(&pmc_threadfreelist_mtx); 2381 if ((pt = LIST_FIRST(&pmc_threadfreelist)) != NULL) { 2382 LIST_REMOVE(pt, pt_next); 2383 pmc_threadfreelist_entries--; 2384 } 2385 mtx_unlock_spin(&pmc_threadfreelist_mtx); 2386 2387 return (pt); 2388 } 2389 2390 /* 2391 * Add a thread descriptor to the free pool. We use this instead of free() 2392 * to maintain a cache of free entries. Additionally, we can safely call 2393 * this function when we cannot call free(), such as in a critical section. 2394 * 2395 */ 2396 static void 2397 pmc_thread_descriptor_pool_free(struct pmc_thread *pt) 2398 { 2399 2400 if (pt == NULL) 2401 return; 2402 2403 memset(pt, 0, THREADENTRY_SIZE); 2404 mtx_lock_spin(&pmc_threadfreelist_mtx); 2405 LIST_INSERT_HEAD(&pmc_threadfreelist, pt, pt_next); 2406 pmc_threadfreelist_entries++; 2407 if (pmc_threadfreelist_entries > pmc_threadfreelist_max) 2408 GROUPTASK_ENQUEUE(&free_gtask); 2409 mtx_unlock_spin(&pmc_threadfreelist_mtx); 2410 } 2411 2412 /* 2413 * A callout to manage the free list. 2414 */ 2415 static void 2416 pmc_thread_descriptor_pool_free_task(void *arg __unused) 2417 { 2418 struct pmc_thread *pt; 2419 LIST_HEAD(, pmc_thread) tmplist; 2420 int delta; 2421 2422 LIST_INIT(&tmplist); 2423 /* Determine what changes, if any, we need to make. */ 2424 mtx_lock_spin(&pmc_threadfreelist_mtx); 2425 delta = pmc_threadfreelist_entries - pmc_threadfreelist_max; 2426 while (delta > 0 && 2427 (pt = LIST_FIRST(&pmc_threadfreelist)) != NULL) { 2428 delta--; 2429 LIST_REMOVE(pt, pt_next); 2430 LIST_INSERT_HEAD(&tmplist, pt, pt_next); 2431 } 2432 mtx_unlock_spin(&pmc_threadfreelist_mtx); 2433 2434 /* If there are entries to free, free them. */ 2435 while (!LIST_EMPTY(&tmplist)) { 2436 pt = LIST_FIRST(&tmplist); 2437 LIST_REMOVE(pt, pt_next); 2438 free(pt, M_PMC); 2439 } 2440 } 2441 2442 /* 2443 * Drain the thread free pool, freeing all allocations. 2444 */ 2445 static void 2446 pmc_thread_descriptor_pool_drain() 2447 { 2448 struct pmc_thread *pt, *next; 2449 2450 LIST_FOREACH_SAFE(pt, &pmc_threadfreelist, pt_next, next) { 2451 LIST_REMOVE(pt, pt_next); 2452 free(pt, M_PMC); 2453 } 2454 } 2455 2456 /* 2457 * find the descriptor corresponding to thread 'td', adding or removing it 2458 * as specified by 'mode'. 2459 * 2460 * Note that this supports additional mode flags in addition to those 2461 * supported by pmc_find_process_descriptor(): 2462 * PMC_FLAG_NOWAIT: Causes the function to not wait for mallocs. 2463 * This makes it safe to call while holding certain other locks. 2464 */ 2465 2466 static struct pmc_thread * 2467 pmc_find_thread_descriptor(struct pmc_process *pp, struct thread *td, 2468 uint32_t mode) 2469 { 2470 struct pmc_thread *pt = NULL, *ptnew = NULL; 2471 int wait_flag; 2472 2473 KASSERT(td != NULL, ("[pmc,%d] called to add NULL td", __LINE__)); 2474 2475 /* 2476 * Pre-allocate memory in the PMC_FLAG_ALLOCATE case prior to 2477 * acquiring the lock. 2478 */ 2479 if (mode & PMC_FLAG_ALLOCATE) { 2480 if ((ptnew = pmc_thread_descriptor_pool_alloc()) == NULL) { 2481 wait_flag = M_WAITOK; 2482 if ((mode & PMC_FLAG_NOWAIT) || in_epoch()) 2483 wait_flag = M_NOWAIT; 2484 2485 ptnew = malloc(THREADENTRY_SIZE, M_PMC, 2486 wait_flag|M_ZERO); 2487 } 2488 } 2489 2490 mtx_lock_spin(pp->pp_tdslock); 2491 2492 LIST_FOREACH(pt, &pp->pp_tds, pt_next) 2493 if (pt->pt_td == td) 2494 break; 2495 2496 if ((mode & PMC_FLAG_REMOVE) && pt != NULL) 2497 LIST_REMOVE(pt, pt_next); 2498 2499 if ((mode & PMC_FLAG_ALLOCATE) && pt == NULL && ptnew != NULL) { 2500 pt = ptnew; 2501 ptnew = NULL; 2502 pt->pt_td = td; 2503 LIST_INSERT_HEAD(&pp->pp_tds, pt, pt_next); 2504 } 2505 2506 mtx_unlock_spin(pp->pp_tdslock); 2507 2508 if (ptnew != NULL) { 2509 free(ptnew, M_PMC); 2510 } 2511 2512 return pt; 2513 } 2514 2515 /* 2516 * Try to add thread descriptors for each thread in a process. 2517 */ 2518 2519 static void 2520 pmc_add_thread_descriptors_from_proc(struct proc *p, struct pmc_process *pp) 2521 { 2522 struct thread *curtd; 2523 struct pmc_thread **tdlist; 2524 int i, tdcnt, tdlistsz; 2525 2526 KASSERT(!PROC_LOCKED(p), ("[pmc,%d] proc unexpectedly locked", 2527 __LINE__)); 2528 tdcnt = 32; 2529 restart: 2530 tdlistsz = roundup2(tdcnt, 32); 2531 2532 tdcnt = 0; 2533 tdlist = malloc(sizeof(struct pmc_thread*) * tdlistsz, M_TEMP, M_WAITOK); 2534 2535 PROC_LOCK(p); 2536 FOREACH_THREAD_IN_PROC(p, curtd) 2537 tdcnt++; 2538 if (tdcnt >= tdlistsz) { 2539 PROC_UNLOCK(p); 2540 free(tdlist, M_TEMP); 2541 goto restart; 2542 } 2543 /* 2544 * Try to add each thread to the list without sleeping. If unable, 2545 * add to a queue to retry after dropping the process lock. 2546 */ 2547 tdcnt = 0; 2548 FOREACH_THREAD_IN_PROC(p, curtd) { 2549 tdlist[tdcnt] = pmc_find_thread_descriptor(pp, curtd, 2550 PMC_FLAG_ALLOCATE|PMC_FLAG_NOWAIT); 2551 if (tdlist[tdcnt] == NULL) { 2552 PROC_UNLOCK(p); 2553 for (i = 0; i <= tdcnt; i++) 2554 pmc_thread_descriptor_pool_free(tdlist[i]); 2555 free(tdlist, M_TEMP); 2556 goto restart; 2557 } 2558 tdcnt++; 2559 } 2560 PROC_UNLOCK(p); 2561 free(tdlist, M_TEMP); 2562 } 2563 2564 /* 2565 * find the descriptor corresponding to process 'p', adding or removing it 2566 * as specified by 'mode'. 2567 */ 2568 2569 static struct pmc_process * 2570 pmc_find_process_descriptor(struct proc *p, uint32_t mode) 2571 { 2572 uint32_t hindex; 2573 struct pmc_process *pp, *ppnew; 2574 struct pmc_processhash *pph; 2575 2576 hindex = PMC_HASH_PTR(p, pmc_processhashmask); 2577 pph = &pmc_processhash[hindex]; 2578 2579 ppnew = NULL; 2580 2581 /* 2582 * Pre-allocate memory in the PMC_FLAG_ALLOCATE case since we 2583 * cannot call malloc(9) once we hold a spin lock. 2584 */ 2585 if (mode & PMC_FLAG_ALLOCATE) 2586 ppnew = malloc(sizeof(struct pmc_process) + md->pmd_npmc * 2587 sizeof(struct pmc_targetstate), M_PMC, M_WAITOK|M_ZERO); 2588 2589 mtx_lock_spin(&pmc_processhash_mtx); 2590 LIST_FOREACH(pp, pph, pp_next) 2591 if (pp->pp_proc == p) 2592 break; 2593 2594 if ((mode & PMC_FLAG_REMOVE) && pp != NULL) 2595 LIST_REMOVE(pp, pp_next); 2596 2597 if ((mode & PMC_FLAG_ALLOCATE) && pp == NULL && 2598 ppnew != NULL) { 2599 ppnew->pp_proc = p; 2600 LIST_INIT(&ppnew->pp_tds); 2601 ppnew->pp_tdslock = mtx_pool_find(pmc_mtxpool, ppnew); 2602 LIST_INSERT_HEAD(pph, ppnew, pp_next); 2603 mtx_unlock_spin(&pmc_processhash_mtx); 2604 pp = ppnew; 2605 ppnew = NULL; 2606 2607 /* Add thread descriptors for this process' current threads. */ 2608 pmc_add_thread_descriptors_from_proc(p, pp); 2609 } 2610 else 2611 mtx_unlock_spin(&pmc_processhash_mtx); 2612 2613 if (ppnew != NULL) 2614 free(ppnew, M_PMC); 2615 2616 return pp; 2617 } 2618 2619 /* 2620 * remove a process descriptor from the process hash table. 2621 */ 2622 2623 static void 2624 pmc_remove_process_descriptor(struct pmc_process *pp) 2625 { 2626 KASSERT(pp->pp_refcnt == 0, 2627 ("[pmc,%d] Removing process descriptor %p with count %d", 2628 __LINE__, pp, pp->pp_refcnt)); 2629 2630 mtx_lock_spin(&pmc_processhash_mtx); 2631 LIST_REMOVE(pp, pp_next); 2632 mtx_unlock_spin(&pmc_processhash_mtx); 2633 } 2634 2635 /* 2636 * destroy a process descriptor. 2637 */ 2638 2639 static void 2640 pmc_destroy_process_descriptor(struct pmc_process *pp) 2641 { 2642 struct pmc_thread *pmc_td; 2643 2644 while ((pmc_td = LIST_FIRST(&pp->pp_tds)) != NULL) { 2645 LIST_REMOVE(pmc_td, pt_next); 2646 pmc_thread_descriptor_pool_free(pmc_td); 2647 } 2648 free(pp, M_PMC); 2649 } 2650 2651 2652 /* 2653 * find an owner descriptor corresponding to proc 'p' 2654 */ 2655 2656 static struct pmc_owner * 2657 pmc_find_owner_descriptor(struct proc *p) 2658 { 2659 uint32_t hindex; 2660 struct pmc_owner *po; 2661 struct pmc_ownerhash *poh; 2662 2663 hindex = PMC_HASH_PTR(p, pmc_ownerhashmask); 2664 poh = &pmc_ownerhash[hindex]; 2665 2666 po = NULL; 2667 LIST_FOREACH(po, poh, po_next) 2668 if (po->po_owner == p) 2669 break; 2670 2671 PMCDBG5(OWN,FND,1, "find-owner proc=%p (%d, %s) hindex=0x%x -> " 2672 "pmc-owner=%p", p, p->p_pid, p->p_comm, hindex, po); 2673 2674 return po; 2675 } 2676 2677 /* 2678 * pmc_allocate_pmc_descriptor 2679 * 2680 * Allocate a pmc descriptor and initialize its 2681 * fields. 2682 */ 2683 2684 static struct pmc * 2685 pmc_allocate_pmc_descriptor(void) 2686 { 2687 struct pmc *pmc; 2688 2689 pmc = malloc(sizeof(struct pmc), M_PMC, M_WAITOK|M_ZERO); 2690 pmc->pm_runcount = counter_u64_alloc(M_WAITOK); 2691 pmc->pm_pcpu_state = malloc(sizeof(struct pmc_pcpu_state)*mp_ncpus, M_PMC, M_WAITOK|M_ZERO); 2692 PMCDBG1(PMC,ALL,1, "allocate-pmc -> pmc=%p", pmc); 2693 2694 return pmc; 2695 } 2696 2697 /* 2698 * Destroy a pmc descriptor. 2699 */ 2700 2701 static void 2702 pmc_destroy_pmc_descriptor(struct pmc *pm) 2703 { 2704 2705 KASSERT(pm->pm_state == PMC_STATE_DELETED || 2706 pm->pm_state == PMC_STATE_FREE, 2707 ("[pmc,%d] destroying non-deleted PMC", __LINE__)); 2708 KASSERT(LIST_EMPTY(&pm->pm_targets), 2709 ("[pmc,%d] destroying pmc with targets", __LINE__)); 2710 KASSERT(pm->pm_owner == NULL, 2711 ("[pmc,%d] destroying pmc attached to an owner", __LINE__)); 2712 KASSERT(counter_u64_fetch(pm->pm_runcount) == 0, 2713 ("[pmc,%d] pmc has non-zero run count %ld", __LINE__, 2714 (unsigned long)counter_u64_fetch(pm->pm_runcount))); 2715 2716 counter_u64_free(pm->pm_runcount); 2717 free(pm->pm_pcpu_state, M_PMC); 2718 free(pm, M_PMC); 2719 } 2720 2721 static void 2722 pmc_wait_for_pmc_idle(struct pmc *pm) 2723 { 2724 #ifdef HWPMC_DEBUG 2725 volatile int maxloop; 2726 2727 maxloop = 100 * pmc_cpu_max(); 2728 #endif 2729 /* 2730 * Loop (with a forced context switch) till the PMC's runcount 2731 * comes down to zero. 2732 */ 2733 pmclog_flush(pm->pm_owner, 1); 2734 while (counter_u64_fetch(pm->pm_runcount) > 0) { 2735 pmclog_flush(pm->pm_owner, 1); 2736 #ifdef HWPMC_DEBUG 2737 maxloop--; 2738 KASSERT(maxloop > 0, 2739 ("[pmc,%d] (ri%d, rc%ld) waiting too long for " 2740 "pmc to be free", __LINE__, 2741 PMC_TO_ROWINDEX(pm), (unsigned long)counter_u64_fetch(pm->pm_runcount))); 2742 #endif 2743 pmc_force_context_switch(); 2744 } 2745 } 2746 2747 /* 2748 * This function does the following things: 2749 * 2750 * - detaches the PMC from hardware 2751 * - unlinks all target threads that were attached to it 2752 * - removes the PMC from its owner's list 2753 * - destroys the PMC private mutex 2754 * 2755 * Once this function completes, the given pmc pointer can be freed by 2756 * calling pmc_destroy_pmc_descriptor(). 2757 */ 2758 2759 static void 2760 pmc_release_pmc_descriptor(struct pmc *pm) 2761 { 2762 enum pmc_mode mode; 2763 struct pmc_hw *phw; 2764 u_int adjri, ri, cpu; 2765 struct pmc_owner *po; 2766 struct pmc_binding pb; 2767 struct pmc_process *pp; 2768 struct pmc_classdep *pcd; 2769 struct pmc_target *ptgt, *tmp; 2770 2771 sx_assert(&pmc_sx, SX_XLOCKED); 2772 2773 KASSERT(pm, ("[pmc,%d] null pmc", __LINE__)); 2774 2775 ri = PMC_TO_ROWINDEX(pm); 2776 pcd = pmc_ri_to_classdep(md, ri, &adjri); 2777 mode = PMC_TO_MODE(pm); 2778 2779 PMCDBG3(PMC,REL,1, "release-pmc pmc=%p ri=%d mode=%d", pm, ri, 2780 mode); 2781 2782 /* 2783 * First, we take the PMC off hardware. 2784 */ 2785 cpu = 0; 2786 if (PMC_IS_SYSTEM_MODE(mode)) { 2787 2788 /* 2789 * A system mode PMC runs on a specific CPU. Switch 2790 * to this CPU and turn hardware off. 2791 */ 2792 pmc_save_cpu_binding(&pb); 2793 2794 cpu = PMC_TO_CPU(pm); 2795 2796 pmc_select_cpu(cpu); 2797 2798 /* switch off non-stalled CPUs */ 2799 pm->pm_pcpu_state[cpu].pps_cpustate = 0; 2800 if (pm->pm_state == PMC_STATE_RUNNING && 2801 pm->pm_pcpu_state[cpu].pps_stalled == 0) { 2802 2803 phw = pmc_pcpu[cpu]->pc_hwpmcs[ri]; 2804 2805 KASSERT(phw->phw_pmc == pm, 2806 ("[pmc, %d] pmc ptr ri(%d) hw(%p) pm(%p)", 2807 __LINE__, ri, phw->phw_pmc, pm)); 2808 PMCDBG2(PMC,REL,2, "stopping cpu=%d ri=%d", cpu, ri); 2809 2810 critical_enter(); 2811 pcd->pcd_stop_pmc(cpu, adjri); 2812 critical_exit(); 2813 } 2814 2815 PMCDBG2(PMC,REL,2, "decfg cpu=%d ri=%d", cpu, ri); 2816 2817 critical_enter(); 2818 pcd->pcd_config_pmc(cpu, adjri, NULL); 2819 critical_exit(); 2820 2821 /* adjust the global and process count of SS mode PMCs */ 2822 if (mode == PMC_MODE_SS && pm->pm_state == PMC_STATE_RUNNING) { 2823 po = pm->pm_owner; 2824 po->po_sscount--; 2825 if (po->po_sscount == 0) { 2826 atomic_subtract_rel_int(&pmc_ss_count, 1); 2827 CK_LIST_REMOVE(po, po_ssnext); 2828 epoch_wait_preempt(global_epoch_preempt); 2829 } 2830 } 2831 2832 pm->pm_state = PMC_STATE_DELETED; 2833 2834 pmc_restore_cpu_binding(&pb); 2835 2836 /* 2837 * We could have references to this PMC structure in 2838 * the per-cpu sample queues. Wait for the queue to 2839 * drain. 2840 */ 2841 pmc_wait_for_pmc_idle(pm); 2842 2843 } else if (PMC_IS_VIRTUAL_MODE(mode)) { 2844 2845 /* 2846 * A virtual PMC could be running on multiple CPUs at 2847 * a given instant. 2848 * 2849 * By marking its state as DELETED, we ensure that 2850 * this PMC is never further scheduled on hardware. 2851 * 2852 * Then we wait till all CPUs are done with this PMC. 2853 */ 2854 pm->pm_state = PMC_STATE_DELETED; 2855 2856 2857 /* Wait for the PMCs runcount to come to zero. */ 2858 pmc_wait_for_pmc_idle(pm); 2859 2860 /* 2861 * At this point the PMC is off all CPUs and cannot be 2862 * freshly scheduled onto a CPU. It is now safe to 2863 * unlink all targets from this PMC. If a 2864 * process-record's refcount falls to zero, we remove 2865 * it from the hash table. The module-wide SX lock 2866 * protects us from races. 2867 */ 2868 LIST_FOREACH_SAFE(ptgt, &pm->pm_targets, pt_next, tmp) { 2869 pp = ptgt->pt_process; 2870 pmc_unlink_target_process(pm, pp); /* frees 'ptgt' */ 2871 2872 PMCDBG1(PMC,REL,3, "pp->refcnt=%d", pp->pp_refcnt); 2873 2874 /* 2875 * If the target process record shows that no 2876 * PMCs are attached to it, reclaim its space. 2877 */ 2878 2879 if (pp->pp_refcnt == 0) { 2880 pmc_remove_process_descriptor(pp); 2881 pmc_destroy_process_descriptor(pp); 2882 } 2883 } 2884 2885 cpu = curthread->td_oncpu; /* setup cpu for pmd_release() */ 2886 2887 } 2888 2889 /* 2890 * Release any MD resources 2891 */ 2892 (void) pcd->pcd_release_pmc(cpu, adjri, pm); 2893 2894 /* 2895 * Update row disposition 2896 */ 2897 2898 if (PMC_IS_SYSTEM_MODE(PMC_TO_MODE(pm))) 2899 PMC_UNMARK_ROW_STANDALONE(ri); 2900 else 2901 PMC_UNMARK_ROW_THREAD(ri); 2902 2903 /* unlink from the owner's list */ 2904 if (pm->pm_owner) { 2905 LIST_REMOVE(pm, pm_next); 2906 pm->pm_owner = NULL; 2907 } 2908 } 2909 2910 /* 2911 * Register an owner and a pmc. 2912 */ 2913 2914 static int 2915 pmc_register_owner(struct proc *p, struct pmc *pmc) 2916 { 2917 struct pmc_owner *po; 2918 2919 sx_assert(&pmc_sx, SX_XLOCKED); 2920 2921 if ((po = pmc_find_owner_descriptor(p)) == NULL) 2922 if ((po = pmc_allocate_owner_descriptor(p)) == NULL) 2923 return ENOMEM; 2924 2925 KASSERT(pmc->pm_owner == NULL, 2926 ("[pmc,%d] attempting to own an initialized PMC", __LINE__)); 2927 pmc->pm_owner = po; 2928 2929 LIST_INSERT_HEAD(&po->po_pmcs, pmc, pm_next); 2930 2931 PROC_LOCK(p); 2932 p->p_flag |= P_HWPMC; 2933 PROC_UNLOCK(p); 2934 2935 if (po->po_flags & PMC_PO_OWNS_LOGFILE) 2936 pmclog_process_pmcallocate(pmc); 2937 2938 PMCDBG2(PMC,REG,1, "register-owner pmc-owner=%p pmc=%p", 2939 po, pmc); 2940 2941 return 0; 2942 } 2943 2944 /* 2945 * Return the current row disposition: 2946 * == 0 => FREE 2947 * > 0 => PROCESS MODE 2948 * < 0 => SYSTEM MODE 2949 */ 2950 2951 int 2952 pmc_getrowdisp(int ri) 2953 { 2954 return pmc_pmcdisp[ri]; 2955 } 2956 2957 /* 2958 * Check if a PMC at row index 'ri' can be allocated to the current 2959 * process. 2960 * 2961 * Allocation can fail if: 2962 * - the current process is already being profiled by a PMC at index 'ri', 2963 * attached to it via OP_PMCATTACH. 2964 * - the current process has already allocated a PMC at index 'ri' 2965 * via OP_ALLOCATE. 2966 */ 2967 2968 static int 2969 pmc_can_allocate_rowindex(struct proc *p, unsigned int ri, int cpu) 2970 { 2971 enum pmc_mode mode; 2972 struct pmc *pm; 2973 struct pmc_owner *po; 2974 struct pmc_process *pp; 2975 2976 PMCDBG5(PMC,ALR,1, "can-allocate-rowindex proc=%p (%d, %s) ri=%d " 2977 "cpu=%d", p, p->p_pid, p->p_comm, ri, cpu); 2978 2979 /* 2980 * We shouldn't have already allocated a process-mode PMC at 2981 * row index 'ri'. 2982 * 2983 * We shouldn't have allocated a system-wide PMC on the same 2984 * CPU and same RI. 2985 */ 2986 if ((po = pmc_find_owner_descriptor(p)) != NULL) 2987 LIST_FOREACH(pm, &po->po_pmcs, pm_next) { 2988 if (PMC_TO_ROWINDEX(pm) == ri) { 2989 mode = PMC_TO_MODE(pm); 2990 if (PMC_IS_VIRTUAL_MODE(mode)) 2991 return EEXIST; 2992 if (PMC_IS_SYSTEM_MODE(mode) && 2993 (int) PMC_TO_CPU(pm) == cpu) 2994 return EEXIST; 2995 } 2996 } 2997 2998 /* 2999 * We also shouldn't be the target of any PMC at this index 3000 * since otherwise a PMC_ATTACH to ourselves will fail. 3001 */ 3002 if ((pp = pmc_find_process_descriptor(p, 0)) != NULL) 3003 if (pp->pp_pmcs[ri].pp_pmc) 3004 return EEXIST; 3005 3006 PMCDBG4(PMC,ALR,2, "can-allocate-rowindex proc=%p (%d, %s) ri=%d ok", 3007 p, p->p_pid, p->p_comm, ri); 3008 3009 return 0; 3010 } 3011 3012 /* 3013 * Check if a given PMC at row index 'ri' can be currently used in 3014 * mode 'mode'. 3015 */ 3016 3017 static int 3018 pmc_can_allocate_row(int ri, enum pmc_mode mode) 3019 { 3020 enum pmc_disp disp; 3021 3022 sx_assert(&pmc_sx, SX_XLOCKED); 3023 3024 PMCDBG2(PMC,ALR,1, "can-allocate-row ri=%d mode=%d", ri, mode); 3025 3026 if (PMC_IS_SYSTEM_MODE(mode)) 3027 disp = PMC_DISP_STANDALONE; 3028 else 3029 disp = PMC_DISP_THREAD; 3030 3031 /* 3032 * check disposition for PMC row 'ri': 3033 * 3034 * Expected disposition Row-disposition Result 3035 * 3036 * STANDALONE STANDALONE or FREE proceed 3037 * STANDALONE THREAD fail 3038 * THREAD THREAD or FREE proceed 3039 * THREAD STANDALONE fail 3040 */ 3041 3042 if (!PMC_ROW_DISP_IS_FREE(ri) && 3043 !(disp == PMC_DISP_THREAD && PMC_ROW_DISP_IS_THREAD(ri)) && 3044 !(disp == PMC_DISP_STANDALONE && PMC_ROW_DISP_IS_STANDALONE(ri))) 3045 return EBUSY; 3046 3047 /* 3048 * All OK 3049 */ 3050 3051 PMCDBG2(PMC,ALR,2, "can-allocate-row ri=%d mode=%d ok", ri, mode); 3052 3053 return 0; 3054 3055 } 3056 3057 /* 3058 * Find a PMC descriptor with user handle 'pmcid' for thread 'td'. 3059 */ 3060 3061 static struct pmc * 3062 pmc_find_pmc_descriptor_in_process(struct pmc_owner *po, pmc_id_t pmcid) 3063 { 3064 struct pmc *pm; 3065 3066 KASSERT(PMC_ID_TO_ROWINDEX(pmcid) < md->pmd_npmc, 3067 ("[pmc,%d] Illegal pmc index %d (max %d)", __LINE__, 3068 PMC_ID_TO_ROWINDEX(pmcid), md->pmd_npmc)); 3069 3070 LIST_FOREACH(pm, &po->po_pmcs, pm_next) 3071 if (pm->pm_id == pmcid) 3072 return pm; 3073 3074 return NULL; 3075 } 3076 3077 static int 3078 pmc_find_pmc(pmc_id_t pmcid, struct pmc **pmc) 3079 { 3080 3081 struct pmc *pm, *opm; 3082 struct pmc_owner *po; 3083 struct pmc_process *pp; 3084 3085 PMCDBG1(PMC,FND,1, "find-pmc id=%d", pmcid); 3086 if (PMC_ID_TO_ROWINDEX(pmcid) >= md->pmd_npmc) 3087 return (EINVAL); 3088 3089 if ((po = pmc_find_owner_descriptor(curthread->td_proc)) == NULL) { 3090 /* 3091 * In case of PMC_F_DESCENDANTS child processes we will not find 3092 * the current process in the owners hash list. Find the owner 3093 * process first and from there lookup the po. 3094 */ 3095 if ((pp = pmc_find_process_descriptor(curthread->td_proc, 3096 PMC_FLAG_NONE)) == NULL) { 3097 return ESRCH; 3098 } else { 3099 opm = pp->pp_pmcs[PMC_ID_TO_ROWINDEX(pmcid)].pp_pmc; 3100 if (opm == NULL) 3101 return ESRCH; 3102 if ((opm->pm_flags & (PMC_F_ATTACHED_TO_OWNER| 3103 PMC_F_DESCENDANTS)) != (PMC_F_ATTACHED_TO_OWNER| 3104 PMC_F_DESCENDANTS)) 3105 return ESRCH; 3106 po = opm->pm_owner; 3107 } 3108 } 3109 3110 if ((pm = pmc_find_pmc_descriptor_in_process(po, pmcid)) == NULL) 3111 return EINVAL; 3112 3113 PMCDBG2(PMC,FND,2, "find-pmc id=%d -> pmc=%p", pmcid, pm); 3114 3115 *pmc = pm; 3116 return 0; 3117 } 3118 3119 /* 3120 * Start a PMC. 3121 */ 3122 3123 static int 3124 pmc_start(struct pmc *pm) 3125 { 3126 enum pmc_mode mode; 3127 struct pmc_owner *po; 3128 struct pmc_binding pb; 3129 struct pmc_classdep *pcd; 3130 int adjri, error, cpu, ri; 3131 3132 KASSERT(pm != NULL, 3133 ("[pmc,%d] null pm", __LINE__)); 3134 3135 mode = PMC_TO_MODE(pm); 3136 ri = PMC_TO_ROWINDEX(pm); 3137 pcd = pmc_ri_to_classdep(md, ri, &adjri); 3138 3139 error = 0; 3140 3141 PMCDBG3(PMC,OPS,1, "start pmc=%p mode=%d ri=%d", pm, mode, ri); 3142 3143 po = pm->pm_owner; 3144 3145 /* 3146 * Disallow PMCSTART if a logfile is required but has not been 3147 * configured yet. 3148 */ 3149 if ((pm->pm_flags & PMC_F_NEEDS_LOGFILE) && 3150 (po->po_flags & PMC_PO_OWNS_LOGFILE) == 0) 3151 return (EDOOFUS); /* programming error */ 3152 3153 /* 3154 * If this is a sampling mode PMC, log mapping information for 3155 * the kernel modules that are currently loaded. 3156 */ 3157 if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm))) 3158 pmc_log_kernel_mappings(pm); 3159 3160 if (PMC_IS_VIRTUAL_MODE(mode)) { 3161 3162 /* 3163 * If a PMCATTACH has never been done on this PMC, 3164 * attach it to its owner process. 3165 */ 3166 3167 if (LIST_EMPTY(&pm->pm_targets)) 3168 error = (pm->pm_flags & PMC_F_ATTACH_DONE) ? ESRCH : 3169 pmc_attach_process(po->po_owner, pm); 3170 3171 /* 3172 * If the PMC is attached to its owner, then force a context 3173 * switch to ensure that the MD state gets set correctly. 3174 */ 3175 3176 if (error == 0) { 3177 pm->pm_state = PMC_STATE_RUNNING; 3178 if (pm->pm_flags & PMC_F_ATTACHED_TO_OWNER) 3179 pmc_force_context_switch(); 3180 } 3181 3182 return (error); 3183 } 3184 3185 3186 /* 3187 * A system-wide PMC. 3188 * 3189 * Add the owner to the global list if this is a system-wide 3190 * sampling PMC. 3191 */ 3192 3193 if (mode == PMC_MODE_SS) { 3194 /* 3195 * Log mapping information for all existing processes in the 3196 * system. Subsequent mappings are logged as they happen; 3197 * see pmc_process_mmap(). 3198 */ 3199 if (po->po_logprocmaps == 0) { 3200 pmc_log_all_process_mappings(po); 3201 po->po_logprocmaps = 1; 3202 } 3203 po->po_sscount++; 3204 if (po->po_sscount == 1) { 3205 atomic_add_rel_int(&pmc_ss_count, 1); 3206 CK_LIST_INSERT_HEAD(&pmc_ss_owners, po, po_ssnext); 3207 PMCDBG1(PMC,OPS,1, "po=%p in global list", po); 3208 } 3209 } 3210 3211 /* 3212 * Move to the CPU associated with this 3213 * PMC, and start the hardware. 3214 */ 3215 3216 pmc_save_cpu_binding(&pb); 3217 3218 cpu = PMC_TO_CPU(pm); 3219 3220 if (!pmc_cpu_is_active(cpu)) 3221 return (ENXIO); 3222 3223 pmc_select_cpu(cpu); 3224 3225 /* 3226 * global PMCs are configured at allocation time 3227 * so write out the initial value and start the PMC. 3228 */ 3229 3230 pm->pm_state = PMC_STATE_RUNNING; 3231 3232 critical_enter(); 3233 if ((error = pcd->pcd_write_pmc(cpu, adjri, 3234 PMC_IS_SAMPLING_MODE(mode) ? 3235 pm->pm_sc.pm_reloadcount : 3236 pm->pm_sc.pm_initial)) == 0) { 3237 /* If a sampling mode PMC, reset stalled state. */ 3238 if (PMC_IS_SAMPLING_MODE(mode)) 3239 pm->pm_pcpu_state[cpu].pps_stalled = 0; 3240 3241 /* Indicate that we desire this to run. Start it. */ 3242 pm->pm_pcpu_state[cpu].pps_cpustate = 1; 3243 error = pcd->pcd_start_pmc(cpu, adjri); 3244 } 3245 critical_exit(); 3246 3247 pmc_restore_cpu_binding(&pb); 3248 3249 return (error); 3250 } 3251 3252 /* 3253 * Stop a PMC. 3254 */ 3255 3256 static int 3257 pmc_stop(struct pmc *pm) 3258 { 3259 struct pmc_owner *po; 3260 struct pmc_binding pb; 3261 struct pmc_classdep *pcd; 3262 int adjri, cpu, error, ri; 3263 3264 KASSERT(pm != NULL, ("[pmc,%d] null pmc", __LINE__)); 3265 3266 PMCDBG3(PMC,OPS,1, "stop pmc=%p mode=%d ri=%d", pm, 3267 PMC_TO_MODE(pm), PMC_TO_ROWINDEX(pm)); 3268 3269 pm->pm_state = PMC_STATE_STOPPED; 3270 3271 /* 3272 * If the PMC is a virtual mode one, changing the state to 3273 * non-RUNNING is enough to ensure that the PMC never gets 3274 * scheduled. 3275 * 3276 * If this PMC is current running on a CPU, then it will 3277 * handled correctly at the time its target process is context 3278 * switched out. 3279 */ 3280 3281 if (PMC_IS_VIRTUAL_MODE(PMC_TO_MODE(pm))) 3282 return 0; 3283 3284 /* 3285 * A system-mode PMC. Move to the CPU associated with 3286 * this PMC, and stop the hardware. We update the 3287 * 'initial count' so that a subsequent PMCSTART will 3288 * resume counting from the current hardware count. 3289 */ 3290 3291 pmc_save_cpu_binding(&pb); 3292 3293 cpu = PMC_TO_CPU(pm); 3294 3295 KASSERT(cpu >= 0 && cpu < pmc_cpu_max(), 3296 ("[pmc,%d] illegal cpu=%d", __LINE__, cpu)); 3297 3298 if (!pmc_cpu_is_active(cpu)) 3299 return ENXIO; 3300 3301 pmc_select_cpu(cpu); 3302 3303 ri = PMC_TO_ROWINDEX(pm); 3304 pcd = pmc_ri_to_classdep(md, ri, &adjri); 3305 3306 pm->pm_pcpu_state[cpu].pps_cpustate = 0; 3307 critical_enter(); 3308 if ((error = pcd->pcd_stop_pmc(cpu, adjri)) == 0) 3309 error = pcd->pcd_read_pmc(cpu, adjri, &pm->pm_sc.pm_initial); 3310 critical_exit(); 3311 3312 pmc_restore_cpu_binding(&pb); 3313 3314 po = pm->pm_owner; 3315 3316 /* remove this owner from the global list of SS PMC owners */ 3317 if (PMC_TO_MODE(pm) == PMC_MODE_SS) { 3318 po->po_sscount--; 3319 if (po->po_sscount == 0) { 3320 atomic_subtract_rel_int(&pmc_ss_count, 1); 3321 CK_LIST_REMOVE(po, po_ssnext); 3322 epoch_wait_preempt(global_epoch_preempt); 3323 PMCDBG1(PMC,OPS,2,"po=%p removed from global list", po); 3324 } 3325 } 3326 3327 return (error); 3328 } 3329 3330 static struct pmc_classdep * 3331 pmc_class_to_classdep(enum pmc_class class) 3332 { 3333 int n; 3334 3335 for (n = 0; n < md->pmd_nclass; n++) 3336 if (md->pmd_classdep[n].pcd_class == class) 3337 return (&md->pmd_classdep[n]); 3338 return (NULL); 3339 } 3340 3341 #if defined(HWPMC_DEBUG) && defined(KTR) 3342 static const char *pmc_op_to_name[] = { 3343 #undef __PMC_OP 3344 #define __PMC_OP(N, D) #N , 3345 __PMC_OPS() 3346 NULL 3347 }; 3348 #endif 3349 3350 /* 3351 * The syscall interface 3352 */ 3353 3354 #define PMC_GET_SX_XLOCK(...) do { \ 3355 sx_xlock(&pmc_sx); \ 3356 if (pmc_hook == NULL) { \ 3357 sx_xunlock(&pmc_sx); \ 3358 return __VA_ARGS__; \ 3359 } \ 3360 } while (0) 3361 3362 #define PMC_DOWNGRADE_SX() do { \ 3363 sx_downgrade(&pmc_sx); \ 3364 is_sx_downgraded = 1; \ 3365 } while (0) 3366 3367 static int 3368 pmc_syscall_handler(struct thread *td, void *syscall_args) 3369 { 3370 int error, is_sx_downgraded, op; 3371 struct pmc_syscall_args *c; 3372 void *pmclog_proc_handle; 3373 void *arg; 3374 3375 c = (struct pmc_syscall_args *)syscall_args; 3376 op = c->pmop_code; 3377 arg = c->pmop_data; 3378 /* PMC isn't set up yet */ 3379 if (pmc_hook == NULL) 3380 return (EINVAL); 3381 if (op == PMC_OP_CONFIGURELOG) { 3382 /* 3383 * We cannot create the logging process inside 3384 * pmclog_configure_log() because there is a LOR 3385 * between pmc_sx and process structure locks. 3386 * Instead, pre-create the process and ignite the loop 3387 * if everything is fine, otherwise direct the process 3388 * to exit. 3389 */ 3390 error = pmclog_proc_create(td, &pmclog_proc_handle); 3391 if (error != 0) 3392 goto done_syscall; 3393 } 3394 3395 PMC_GET_SX_XLOCK(ENOSYS); 3396 is_sx_downgraded = 0; 3397 PMCDBG3(MOD,PMS,1, "syscall op=%d \"%s\" arg=%p", op, 3398 pmc_op_to_name[op], arg); 3399 3400 error = 0; 3401 counter_u64_add(pmc_stats.pm_syscalls, 1); 3402 3403 switch (op) { 3404 3405 3406 /* 3407 * Configure a log file. 3408 * 3409 * XXX This OP will be reworked. 3410 */ 3411 3412 case PMC_OP_CONFIGURELOG: 3413 { 3414 struct proc *p; 3415 struct pmc *pm; 3416 struct pmc_owner *po; 3417 struct pmc_op_configurelog cl; 3418 3419 if ((error = copyin(arg, &cl, sizeof(cl))) != 0) { 3420 pmclog_proc_ignite(pmclog_proc_handle, NULL); 3421 break; 3422 } 3423 3424 /* mark this process as owning a log file */ 3425 p = td->td_proc; 3426 if ((po = pmc_find_owner_descriptor(p)) == NULL) 3427 if ((po = pmc_allocate_owner_descriptor(p)) == NULL) { 3428 pmclog_proc_ignite(pmclog_proc_handle, NULL); 3429 error = ENOMEM; 3430 break; 3431 } 3432 3433 /* 3434 * If a valid fd was passed in, try to configure that, 3435 * otherwise if 'fd' was less than zero and there was 3436 * a log file configured, flush its buffers and 3437 * de-configure it. 3438 */ 3439 if (cl.pm_logfd >= 0) { 3440 error = pmclog_configure_log(md, po, cl.pm_logfd); 3441 pmclog_proc_ignite(pmclog_proc_handle, error == 0 ? 3442 po : NULL); 3443 } else if (po->po_flags & PMC_PO_OWNS_LOGFILE) { 3444 pmclog_proc_ignite(pmclog_proc_handle, NULL); 3445 error = pmclog_close(po); 3446 if (error == 0) { 3447 LIST_FOREACH(pm, &po->po_pmcs, pm_next) 3448 if (pm->pm_flags & PMC_F_NEEDS_LOGFILE && 3449 pm->pm_state == PMC_STATE_RUNNING) 3450 pmc_stop(pm); 3451 error = pmclog_deconfigure_log(po); 3452 } 3453 } else { 3454 pmclog_proc_ignite(pmclog_proc_handle, NULL); 3455 error = EINVAL; 3456 } 3457 } 3458 break; 3459 3460 /* 3461 * Flush a log file. 3462 */ 3463 3464 case PMC_OP_FLUSHLOG: 3465 { 3466 struct pmc_owner *po; 3467 3468 sx_assert(&pmc_sx, SX_XLOCKED); 3469 3470 if ((po = pmc_find_owner_descriptor(td->td_proc)) == NULL) { 3471 error = EINVAL; 3472 break; 3473 } 3474 3475 error = pmclog_flush(po, 0); 3476 } 3477 break; 3478 3479 /* 3480 * Close a log file. 3481 */ 3482 3483 case PMC_OP_CLOSELOG: 3484 { 3485 struct pmc_owner *po; 3486 3487 sx_assert(&pmc_sx, SX_XLOCKED); 3488 3489 if ((po = pmc_find_owner_descriptor(td->td_proc)) == NULL) { 3490 error = EINVAL; 3491 break; 3492 } 3493 3494 error = pmclog_close(po); 3495 } 3496 break; 3497 3498 /* 3499 * Retrieve hardware configuration. 3500 */ 3501 3502 case PMC_OP_GETCPUINFO: /* CPU information */ 3503 { 3504 struct pmc_op_getcpuinfo gci; 3505 struct pmc_classinfo *pci; 3506 struct pmc_classdep *pcd; 3507 int cl; 3508 3509 gci.pm_cputype = md->pmd_cputype; 3510 gci.pm_ncpu = pmc_cpu_max(); 3511 gci.pm_npmc = md->pmd_npmc; 3512 gci.pm_nclass = md->pmd_nclass; 3513 pci = gci.pm_classes; 3514 pcd = md->pmd_classdep; 3515 for (cl = 0; cl < md->pmd_nclass; cl++, pci++, pcd++) { 3516 pci->pm_caps = pcd->pcd_caps; 3517 pci->pm_class = pcd->pcd_class; 3518 pci->pm_width = pcd->pcd_width; 3519 pci->pm_num = pcd->pcd_num; 3520 } 3521 error = copyout(&gci, arg, sizeof(gci)); 3522 } 3523 break; 3524 3525 /* 3526 * Retrieve soft events list. 3527 */ 3528 case PMC_OP_GETDYNEVENTINFO: 3529 { 3530 enum pmc_class cl; 3531 enum pmc_event ev; 3532 struct pmc_op_getdyneventinfo *gei; 3533 struct pmc_dyn_event_descr dev; 3534 struct pmc_soft *ps; 3535 uint32_t nevent; 3536 3537 sx_assert(&pmc_sx, SX_LOCKED); 3538 3539 gei = (struct pmc_op_getdyneventinfo *) arg; 3540 3541 if ((error = copyin(&gei->pm_class, &cl, sizeof(cl))) != 0) 3542 break; 3543 3544 /* Only SOFT class is dynamic. */ 3545 if (cl != PMC_CLASS_SOFT) { 3546 error = EINVAL; 3547 break; 3548 } 3549 3550 nevent = 0; 3551 for (ev = PMC_EV_SOFT_FIRST; (int)ev <= PMC_EV_SOFT_LAST; ev++) { 3552 ps = pmc_soft_ev_acquire(ev); 3553 if (ps == NULL) 3554 continue; 3555 bcopy(&ps->ps_ev, &dev, sizeof(dev)); 3556 pmc_soft_ev_release(ps); 3557 3558 error = copyout(&dev, 3559 &gei->pm_events[nevent], 3560 sizeof(struct pmc_dyn_event_descr)); 3561 if (error != 0) 3562 break; 3563 nevent++; 3564 } 3565 if (error != 0) 3566 break; 3567 3568 error = copyout(&nevent, &gei->pm_nevent, 3569 sizeof(nevent)); 3570 } 3571 break; 3572 3573 /* 3574 * Get module statistics 3575 */ 3576 3577 case PMC_OP_GETDRIVERSTATS: 3578 { 3579 struct pmc_op_getdriverstats gms; 3580 #define CFETCH(a, b, field) a.field = counter_u64_fetch(b.field) 3581 CFETCH(gms, pmc_stats, pm_intr_ignored); 3582 CFETCH(gms, pmc_stats, pm_intr_processed); 3583 CFETCH(gms, pmc_stats, pm_intr_bufferfull); 3584 CFETCH(gms, pmc_stats, pm_syscalls); 3585 CFETCH(gms, pmc_stats, pm_syscall_errors); 3586 CFETCH(gms, pmc_stats, pm_buffer_requests); 3587 CFETCH(gms, pmc_stats, pm_buffer_requests_failed); 3588 CFETCH(gms, pmc_stats, pm_log_sweeps); 3589 #undef CFETCH 3590 error = copyout(&gms, arg, sizeof(gms)); 3591 } 3592 break; 3593 3594 3595 /* 3596 * Retrieve module version number 3597 */ 3598 3599 case PMC_OP_GETMODULEVERSION: 3600 { 3601 uint32_t cv, modv; 3602 3603 /* retrieve the client's idea of the ABI version */ 3604 if ((error = copyin(arg, &cv, sizeof(uint32_t))) != 0) 3605 break; 3606 /* don't service clients newer than our driver */ 3607 modv = PMC_VERSION; 3608 if ((cv & 0xFFFF0000) > (modv & 0xFFFF0000)) { 3609 error = EPROGMISMATCH; 3610 break; 3611 } 3612 error = copyout(&modv, arg, sizeof(int)); 3613 } 3614 break; 3615 3616 3617 /* 3618 * Retrieve the state of all the PMCs on a given 3619 * CPU. 3620 */ 3621 3622 case PMC_OP_GETPMCINFO: 3623 { 3624 int ari; 3625 struct pmc *pm; 3626 size_t pmcinfo_size; 3627 uint32_t cpu, n, npmc; 3628 struct pmc_owner *po; 3629 struct pmc_binding pb; 3630 struct pmc_classdep *pcd; 3631 struct pmc_info *p, *pmcinfo; 3632 struct pmc_op_getpmcinfo *gpi; 3633 3634 PMC_DOWNGRADE_SX(); 3635 3636 gpi = (struct pmc_op_getpmcinfo *) arg; 3637 3638 if ((error = copyin(&gpi->pm_cpu, &cpu, sizeof(cpu))) != 0) 3639 break; 3640 3641 if (cpu >= pmc_cpu_max()) { 3642 error = EINVAL; 3643 break; 3644 } 3645 3646 if (!pmc_cpu_is_active(cpu)) { 3647 error = ENXIO; 3648 break; 3649 } 3650 3651 /* switch to CPU 'cpu' */ 3652 pmc_save_cpu_binding(&pb); 3653 pmc_select_cpu(cpu); 3654 3655 npmc = md->pmd_npmc; 3656 3657 pmcinfo_size = npmc * sizeof(struct pmc_info); 3658 pmcinfo = malloc(pmcinfo_size, M_PMC, M_WAITOK); 3659 3660 p = pmcinfo; 3661 3662 for (n = 0; n < md->pmd_npmc; n++, p++) { 3663 3664 pcd = pmc_ri_to_classdep(md, n, &ari); 3665 3666 KASSERT(pcd != NULL, 3667 ("[pmc,%d] null pcd ri=%d", __LINE__, n)); 3668 3669 if ((error = pcd->pcd_describe(cpu, ari, p, &pm)) != 0) 3670 break; 3671 3672 if (PMC_ROW_DISP_IS_STANDALONE(n)) 3673 p->pm_rowdisp = PMC_DISP_STANDALONE; 3674 else if (PMC_ROW_DISP_IS_THREAD(n)) 3675 p->pm_rowdisp = PMC_DISP_THREAD; 3676 else 3677 p->pm_rowdisp = PMC_DISP_FREE; 3678 3679 p->pm_ownerpid = -1; 3680 3681 if (pm == NULL) /* no PMC associated */ 3682 continue; 3683 3684 po = pm->pm_owner; 3685 3686 KASSERT(po->po_owner != NULL, 3687 ("[pmc,%d] pmc_owner had a null proc pointer", 3688 __LINE__)); 3689 3690 p->pm_ownerpid = po->po_owner->p_pid; 3691 p->pm_mode = PMC_TO_MODE(pm); 3692 p->pm_event = pm->pm_event; 3693 p->pm_flags = pm->pm_flags; 3694 3695 if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm))) 3696 p->pm_reloadcount = 3697 pm->pm_sc.pm_reloadcount; 3698 } 3699 3700 pmc_restore_cpu_binding(&pb); 3701 3702 /* now copy out the PMC info collected */ 3703 if (error == 0) 3704 error = copyout(pmcinfo, &gpi->pm_pmcs, pmcinfo_size); 3705 3706 free(pmcinfo, M_PMC); 3707 } 3708 break; 3709 3710 3711 /* 3712 * Set the administrative state of a PMC. I.e. whether 3713 * the PMC is to be used or not. 3714 */ 3715 3716 case PMC_OP_PMCADMIN: 3717 { 3718 int cpu, ri; 3719 enum pmc_state request; 3720 struct pmc_cpu *pc; 3721 struct pmc_hw *phw; 3722 struct pmc_op_pmcadmin pma; 3723 struct pmc_binding pb; 3724 3725 sx_assert(&pmc_sx, SX_XLOCKED); 3726 3727 KASSERT(td == curthread, 3728 ("[pmc,%d] td != curthread", __LINE__)); 3729 3730 error = priv_check(td, PRIV_PMC_MANAGE); 3731 if (error) 3732 break; 3733 3734 if ((error = copyin(arg, &pma, sizeof(pma))) != 0) 3735 break; 3736 3737 cpu = pma.pm_cpu; 3738 3739 if (cpu < 0 || cpu >= (int) pmc_cpu_max()) { 3740 error = EINVAL; 3741 break; 3742 } 3743 3744 if (!pmc_cpu_is_active(cpu)) { 3745 error = ENXIO; 3746 break; 3747 } 3748 3749 request = pma.pm_state; 3750 3751 if (request != PMC_STATE_DISABLED && 3752 request != PMC_STATE_FREE) { 3753 error = EINVAL; 3754 break; 3755 } 3756 3757 ri = pma.pm_pmc; /* pmc id == row index */ 3758 if (ri < 0 || ri >= (int) md->pmd_npmc) { 3759 error = EINVAL; 3760 break; 3761 } 3762 3763 /* 3764 * We can't disable a PMC with a row-index allocated 3765 * for process virtual PMCs. 3766 */ 3767 3768 if (PMC_ROW_DISP_IS_THREAD(ri) && 3769 request == PMC_STATE_DISABLED) { 3770 error = EBUSY; 3771 break; 3772 } 3773 3774 /* 3775 * otherwise, this PMC on this CPU is either free or 3776 * in system-wide mode. 3777 */ 3778 3779 pmc_save_cpu_binding(&pb); 3780 pmc_select_cpu(cpu); 3781 3782 pc = pmc_pcpu[cpu]; 3783 phw = pc->pc_hwpmcs[ri]; 3784 3785 /* 3786 * XXX do we need some kind of 'forced' disable? 3787 */ 3788 3789 if (phw->phw_pmc == NULL) { 3790 if (request == PMC_STATE_DISABLED && 3791 (phw->phw_state & PMC_PHW_FLAG_IS_ENABLED)) { 3792 phw->phw_state &= ~PMC_PHW_FLAG_IS_ENABLED; 3793 PMC_MARK_ROW_STANDALONE(ri); 3794 } else if (request == PMC_STATE_FREE && 3795 (phw->phw_state & PMC_PHW_FLAG_IS_ENABLED) == 0) { 3796 phw->phw_state |= PMC_PHW_FLAG_IS_ENABLED; 3797 PMC_UNMARK_ROW_STANDALONE(ri); 3798 } 3799 /* other cases are a no-op */ 3800 } else 3801 error = EBUSY; 3802 3803 pmc_restore_cpu_binding(&pb); 3804 } 3805 break; 3806 3807 3808 /* 3809 * Allocate a PMC. 3810 */ 3811 3812 case PMC_OP_PMCALLOCATE: 3813 { 3814 int adjri, n; 3815 u_int cpu; 3816 uint32_t caps; 3817 struct pmc *pmc; 3818 enum pmc_mode mode; 3819 struct pmc_hw *phw; 3820 struct pmc_binding pb; 3821 struct pmc_classdep *pcd; 3822 struct pmc_op_pmcallocate pa; 3823 3824 if ((error = copyin(arg, &pa, sizeof(pa))) != 0) 3825 break; 3826 3827 caps = pa.pm_caps; 3828 mode = pa.pm_mode; 3829 cpu = pa.pm_cpu; 3830 3831 if ((mode != PMC_MODE_SS && mode != PMC_MODE_SC && 3832 mode != PMC_MODE_TS && mode != PMC_MODE_TC) || 3833 (cpu != (u_int) PMC_CPU_ANY && cpu >= pmc_cpu_max())) { 3834 error = EINVAL; 3835 break; 3836 } 3837 3838 /* 3839 * Virtual PMCs should only ask for a default CPU. 3840 * System mode PMCs need to specify a non-default CPU. 3841 */ 3842 3843 if ((PMC_IS_VIRTUAL_MODE(mode) && cpu != (u_int) PMC_CPU_ANY) || 3844 (PMC_IS_SYSTEM_MODE(mode) && cpu == (u_int) PMC_CPU_ANY)) { 3845 error = EINVAL; 3846 break; 3847 } 3848 3849 /* 3850 * Check that an inactive CPU is not being asked for. 3851 */ 3852 3853 if (PMC_IS_SYSTEM_MODE(mode) && !pmc_cpu_is_active(cpu)) { 3854 error = ENXIO; 3855 break; 3856 } 3857 3858 /* 3859 * Refuse an allocation for a system-wide PMC if this 3860 * process has been jailed, or if this process lacks 3861 * super-user credentials and the sysctl tunable 3862 * 'security.bsd.unprivileged_syspmcs' is zero. 3863 */ 3864 3865 if (PMC_IS_SYSTEM_MODE(mode)) { 3866 if (jailed(curthread->td_ucred)) { 3867 error = EPERM; 3868 break; 3869 } 3870 if (!pmc_unprivileged_syspmcs) { 3871 error = priv_check(curthread, 3872 PRIV_PMC_SYSTEM); 3873 if (error) 3874 break; 3875 } 3876 } 3877 3878 /* 3879 * Look for valid values for 'pm_flags' 3880 */ 3881 3882 if ((pa.pm_flags & ~(PMC_F_DESCENDANTS | PMC_F_LOG_PROCCSW | 3883 PMC_F_LOG_PROCEXIT | PMC_F_CALLCHAIN | 3884 PMC_F_USERCALLCHAIN)) != 0) { 3885 error = EINVAL; 3886 break; 3887 } 3888 3889 /* PMC_F_USERCALLCHAIN is only valid with PMC_F_CALLCHAIN */ 3890 if ((pa.pm_flags & (PMC_F_CALLCHAIN | PMC_F_USERCALLCHAIN)) == 3891 PMC_F_USERCALLCHAIN) { 3892 error = EINVAL; 3893 break; 3894 } 3895 3896 /* PMC_F_USERCALLCHAIN is only valid for sampling mode */ 3897 if (pa.pm_flags & PMC_F_USERCALLCHAIN && 3898 mode != PMC_MODE_TS && mode != PMC_MODE_SS) { 3899 error = EINVAL; 3900 break; 3901 } 3902 3903 /* process logging options are not allowed for system PMCs */ 3904 if (PMC_IS_SYSTEM_MODE(mode) && (pa.pm_flags & 3905 (PMC_F_LOG_PROCCSW | PMC_F_LOG_PROCEXIT))) { 3906 error = EINVAL; 3907 break; 3908 } 3909 3910 /* 3911 * All sampling mode PMCs need to be able to interrupt the 3912 * CPU. 3913 */ 3914 if (PMC_IS_SAMPLING_MODE(mode)) 3915 caps |= PMC_CAP_INTERRUPT; 3916 3917 /* A valid class specifier should have been passed in. */ 3918 pcd = pmc_class_to_classdep(pa.pm_class); 3919 if (pcd == NULL) { 3920 error = EINVAL; 3921 break; 3922 } 3923 3924 /* The requested PMC capabilities should be feasible. */ 3925 if ((pcd->pcd_caps & caps) != caps) { 3926 error = EOPNOTSUPP; 3927 break; 3928 } 3929 3930 PMCDBG4(PMC,ALL,2, "event=%d caps=0x%x mode=%d cpu=%d", 3931 pa.pm_ev, caps, mode, cpu); 3932 3933 pmc = pmc_allocate_pmc_descriptor(); 3934 pmc->pm_id = PMC_ID_MAKE_ID(cpu,pa.pm_mode,pa.pm_class, 3935 PMC_ID_INVALID); 3936 pmc->pm_event = pa.pm_ev; 3937 pmc->pm_state = PMC_STATE_FREE; 3938 pmc->pm_caps = caps; 3939 pmc->pm_flags = pa.pm_flags; 3940 3941 /* XXX set lower bound on sampling for process counters */ 3942 if (PMC_IS_SAMPLING_MODE(mode)) 3943 pmc->pm_sc.pm_reloadcount = pa.pm_count; 3944 else 3945 pmc->pm_sc.pm_initial = pa.pm_count; 3946 3947 /* switch thread to CPU 'cpu' */ 3948 pmc_save_cpu_binding(&pb); 3949 3950 #define PMC_IS_SHAREABLE_PMC(cpu, n) \ 3951 (pmc_pcpu[(cpu)]->pc_hwpmcs[(n)]->phw_state & \ 3952 PMC_PHW_FLAG_IS_SHAREABLE) 3953 #define PMC_IS_UNALLOCATED(cpu, n) \ 3954 (pmc_pcpu[(cpu)]->pc_hwpmcs[(n)]->phw_pmc == NULL) 3955 3956 if (PMC_IS_SYSTEM_MODE(mode)) { 3957 pmc_select_cpu(cpu); 3958 for (n = pcd->pcd_ri; n < (int) md->pmd_npmc; n++) { 3959 pcd = pmc_ri_to_classdep(md, n, &adjri); 3960 if (pmc_can_allocate_row(n, mode) == 0 && 3961 pmc_can_allocate_rowindex( 3962 curthread->td_proc, n, cpu) == 0 && 3963 (PMC_IS_UNALLOCATED(cpu, n) || 3964 PMC_IS_SHAREABLE_PMC(cpu, n)) && 3965 pcd->pcd_allocate_pmc(cpu, adjri, pmc, 3966 &pa) == 0) 3967 break; 3968 } 3969 } else { 3970 /* Process virtual mode */ 3971 for (n = pcd->pcd_ri; n < (int) md->pmd_npmc; n++) { 3972 pcd = pmc_ri_to_classdep(md, n, &adjri); 3973 if (pmc_can_allocate_row(n, mode) == 0 && 3974 pmc_can_allocate_rowindex( 3975 curthread->td_proc, n, 3976 PMC_CPU_ANY) == 0 && 3977 pcd->pcd_allocate_pmc(curthread->td_oncpu, 3978 adjri, pmc, &pa) == 0) 3979 break; 3980 } 3981 } 3982 3983 #undef PMC_IS_UNALLOCATED 3984 #undef PMC_IS_SHAREABLE_PMC 3985 3986 pmc_restore_cpu_binding(&pb); 3987 3988 if (n == (int) md->pmd_npmc) { 3989 pmc_destroy_pmc_descriptor(pmc); 3990 pmc = NULL; 3991 error = EINVAL; 3992 break; 3993 } 3994 3995 /* Fill in the correct value in the ID field */ 3996 pmc->pm_id = PMC_ID_MAKE_ID(cpu,mode,pa.pm_class,n); 3997 3998 PMCDBG5(PMC,ALL,2, "ev=%d class=%d mode=%d n=%d -> pmcid=%x", 3999 pmc->pm_event, pa.pm_class, mode, n, pmc->pm_id); 4000 4001 /* Process mode PMCs with logging enabled need log files */ 4002 if (pmc->pm_flags & (PMC_F_LOG_PROCEXIT | PMC_F_LOG_PROCCSW)) 4003 pmc->pm_flags |= PMC_F_NEEDS_LOGFILE; 4004 4005 /* All system mode sampling PMCs require a log file */ 4006 if (PMC_IS_SAMPLING_MODE(mode) && PMC_IS_SYSTEM_MODE(mode)) 4007 pmc->pm_flags |= PMC_F_NEEDS_LOGFILE; 4008 4009 /* 4010 * Configure global pmc's immediately 4011 */ 4012 4013 if (PMC_IS_SYSTEM_MODE(PMC_TO_MODE(pmc))) { 4014 4015 pmc_save_cpu_binding(&pb); 4016 pmc_select_cpu(cpu); 4017 4018 phw = pmc_pcpu[cpu]->pc_hwpmcs[n]; 4019 pcd = pmc_ri_to_classdep(md, n, &adjri); 4020 4021 if ((phw->phw_state & PMC_PHW_FLAG_IS_ENABLED) == 0 || 4022 (error = pcd->pcd_config_pmc(cpu, adjri, pmc)) != 0) { 4023 (void) pcd->pcd_release_pmc(cpu, adjri, pmc); 4024 pmc_destroy_pmc_descriptor(pmc); 4025 pmc = NULL; 4026 pmc_restore_cpu_binding(&pb); 4027 error = EPERM; 4028 break; 4029 } 4030 4031 pmc_restore_cpu_binding(&pb); 4032 } 4033 4034 pmc->pm_state = PMC_STATE_ALLOCATED; 4035 pmc->pm_class = pa.pm_class; 4036 4037 /* 4038 * mark row disposition 4039 */ 4040 4041 if (PMC_IS_SYSTEM_MODE(mode)) 4042 PMC_MARK_ROW_STANDALONE(n); 4043 else 4044 PMC_MARK_ROW_THREAD(n); 4045 4046 /* 4047 * Register this PMC with the current thread as its owner. 4048 */ 4049 4050 if ((error = 4051 pmc_register_owner(curthread->td_proc, pmc)) != 0) { 4052 pmc_release_pmc_descriptor(pmc); 4053 pmc_destroy_pmc_descriptor(pmc); 4054 pmc = NULL; 4055 break; 4056 } 4057 4058 4059 /* 4060 * Return the allocated index. 4061 */ 4062 4063 pa.pm_pmcid = pmc->pm_id; 4064 4065 error = copyout(&pa, arg, sizeof(pa)); 4066 } 4067 break; 4068 4069 4070 /* 4071 * Attach a PMC to a process. 4072 */ 4073 4074 case PMC_OP_PMCATTACH: 4075 { 4076 struct pmc *pm; 4077 struct proc *p; 4078 struct pmc_op_pmcattach a; 4079 4080 sx_assert(&pmc_sx, SX_XLOCKED); 4081 4082 if ((error = copyin(arg, &a, sizeof(a))) != 0) 4083 break; 4084 4085 if (a.pm_pid < 0) { 4086 error = EINVAL; 4087 break; 4088 } else if (a.pm_pid == 0) 4089 a.pm_pid = td->td_proc->p_pid; 4090 4091 if ((error = pmc_find_pmc(a.pm_pmc, &pm)) != 0) 4092 break; 4093 4094 if (PMC_IS_SYSTEM_MODE(PMC_TO_MODE(pm))) { 4095 error = EINVAL; 4096 break; 4097 } 4098 4099 /* PMCs may be (re)attached only when allocated or stopped */ 4100 if (pm->pm_state == PMC_STATE_RUNNING) { 4101 error = EBUSY; 4102 break; 4103 } else if (pm->pm_state != PMC_STATE_ALLOCATED && 4104 pm->pm_state != PMC_STATE_STOPPED) { 4105 error = EINVAL; 4106 break; 4107 } 4108 4109 /* lookup pid */ 4110 if ((p = pfind(a.pm_pid)) == NULL) { 4111 error = ESRCH; 4112 break; 4113 } 4114 4115 /* 4116 * Ignore processes that are working on exiting. 4117 */ 4118 if (p->p_flag & P_WEXIT) { 4119 error = ESRCH; 4120 PROC_UNLOCK(p); /* pfind() returns a locked process */ 4121 break; 4122 } 4123 4124 /* 4125 * we are allowed to attach a PMC to a process if 4126 * we can debug it. 4127 */ 4128 error = p_candebug(curthread, p); 4129 4130 PROC_UNLOCK(p); 4131 4132 if (error == 0) 4133 error = pmc_attach_process(p, pm); 4134 } 4135 break; 4136 4137 4138 /* 4139 * Detach an attached PMC from a process. 4140 */ 4141 4142 case PMC_OP_PMCDETACH: 4143 { 4144 struct pmc *pm; 4145 struct proc *p; 4146 struct pmc_op_pmcattach a; 4147 4148 if ((error = copyin(arg, &a, sizeof(a))) != 0) 4149 break; 4150 4151 if (a.pm_pid < 0) { 4152 error = EINVAL; 4153 break; 4154 } else if (a.pm_pid == 0) 4155 a.pm_pid = td->td_proc->p_pid; 4156 4157 if ((error = pmc_find_pmc(a.pm_pmc, &pm)) != 0) 4158 break; 4159 4160 if ((p = pfind(a.pm_pid)) == NULL) { 4161 error = ESRCH; 4162 break; 4163 } 4164 4165 /* 4166 * Treat processes that are in the process of exiting 4167 * as if they were not present. 4168 */ 4169 4170 if (p->p_flag & P_WEXIT) 4171 error = ESRCH; 4172 4173 PROC_UNLOCK(p); /* pfind() returns a locked process */ 4174 4175 if (error == 0) 4176 error = pmc_detach_process(p, pm); 4177 } 4178 break; 4179 4180 4181 /* 4182 * Retrieve the MSR number associated with the counter 4183 * 'pmc_id'. This allows processes to directly use RDPMC 4184 * instructions to read their PMCs, without the overhead of a 4185 * system call. 4186 */ 4187 4188 case PMC_OP_PMCGETMSR: 4189 { 4190 int adjri, ri; 4191 struct pmc *pm; 4192 struct pmc_target *pt; 4193 struct pmc_op_getmsr gm; 4194 struct pmc_classdep *pcd; 4195 4196 PMC_DOWNGRADE_SX(); 4197 4198 if ((error = copyin(arg, &gm, sizeof(gm))) != 0) 4199 break; 4200 4201 if ((error = pmc_find_pmc(gm.pm_pmcid, &pm)) != 0) 4202 break; 4203 4204 /* 4205 * The allocated PMC has to be a process virtual PMC, 4206 * i.e., of type MODE_T[CS]. Global PMCs can only be 4207 * read using the PMCREAD operation since they may be 4208 * allocated on a different CPU than the one we could 4209 * be running on at the time of the RDPMC instruction. 4210 * 4211 * The GETMSR operation is not allowed for PMCs that 4212 * are inherited across processes. 4213 */ 4214 4215 if (!PMC_IS_VIRTUAL_MODE(PMC_TO_MODE(pm)) || 4216 (pm->pm_flags & PMC_F_DESCENDANTS)) { 4217 error = EINVAL; 4218 break; 4219 } 4220 4221 /* 4222 * It only makes sense to use a RDPMC (or its 4223 * equivalent instruction on non-x86 architectures) on 4224 * a process that has allocated and attached a PMC to 4225 * itself. Conversely the PMC is only allowed to have 4226 * one process attached to it -- its owner. 4227 */ 4228 4229 if ((pt = LIST_FIRST(&pm->pm_targets)) == NULL || 4230 LIST_NEXT(pt, pt_next) != NULL || 4231 pt->pt_process->pp_proc != pm->pm_owner->po_owner) { 4232 error = EINVAL; 4233 break; 4234 } 4235 4236 ri = PMC_TO_ROWINDEX(pm); 4237 pcd = pmc_ri_to_classdep(md, ri, &adjri); 4238 4239 /* PMC class has no 'GETMSR' support */ 4240 if (pcd->pcd_get_msr == NULL) { 4241 error = ENOSYS; 4242 break; 4243 } 4244 4245 if ((error = (*pcd->pcd_get_msr)(adjri, &gm.pm_msr)) < 0) 4246 break; 4247 4248 if ((error = copyout(&gm, arg, sizeof(gm))) < 0) 4249 break; 4250 4251 /* 4252 * Mark our process as using MSRs. Update machine 4253 * state using a forced context switch. 4254 */ 4255 4256 pt->pt_process->pp_flags |= PMC_PP_ENABLE_MSR_ACCESS; 4257 pmc_force_context_switch(); 4258 4259 } 4260 break; 4261 4262 /* 4263 * Release an allocated PMC 4264 */ 4265 4266 case PMC_OP_PMCRELEASE: 4267 { 4268 pmc_id_t pmcid; 4269 struct pmc *pm; 4270 struct pmc_owner *po; 4271 struct pmc_op_simple sp; 4272 4273 /* 4274 * Find PMC pointer for the named PMC. 4275 * 4276 * Use pmc_release_pmc_descriptor() to switch off the 4277 * PMC, remove all its target threads, and remove the 4278 * PMC from its owner's list. 4279 * 4280 * Remove the owner record if this is the last PMC 4281 * owned. 4282 * 4283 * Free up space. 4284 */ 4285 4286 if ((error = copyin(arg, &sp, sizeof(sp))) != 0) 4287 break; 4288 4289 pmcid = sp.pm_pmcid; 4290 4291 if ((error = pmc_find_pmc(pmcid, &pm)) != 0) 4292 break; 4293 4294 po = pm->pm_owner; 4295 pmc_release_pmc_descriptor(pm); 4296 pmc_maybe_remove_owner(po); 4297 pmc_destroy_pmc_descriptor(pm); 4298 } 4299 break; 4300 4301 4302 /* 4303 * Read and/or write a PMC. 4304 */ 4305 4306 case PMC_OP_PMCRW: 4307 { 4308 int adjri; 4309 struct pmc *pm; 4310 uint32_t cpu, ri; 4311 pmc_value_t oldvalue; 4312 struct pmc_binding pb; 4313 struct pmc_op_pmcrw prw; 4314 struct pmc_classdep *pcd; 4315 struct pmc_op_pmcrw *pprw; 4316 4317 PMC_DOWNGRADE_SX(); 4318 4319 if ((error = copyin(arg, &prw, sizeof(prw))) != 0) 4320 break; 4321 4322 ri = 0; 4323 PMCDBG2(PMC,OPS,1, "rw id=%d flags=0x%x", prw.pm_pmcid, 4324 prw.pm_flags); 4325 4326 /* must have at least one flag set */ 4327 if ((prw.pm_flags & (PMC_F_OLDVALUE|PMC_F_NEWVALUE)) == 0) { 4328 error = EINVAL; 4329 break; 4330 } 4331 4332 /* locate pmc descriptor */ 4333 if ((error = pmc_find_pmc(prw.pm_pmcid, &pm)) != 0) 4334 break; 4335 4336 /* Can't read a PMC that hasn't been started. */ 4337 if (pm->pm_state != PMC_STATE_ALLOCATED && 4338 pm->pm_state != PMC_STATE_STOPPED && 4339 pm->pm_state != PMC_STATE_RUNNING) { 4340 error = EINVAL; 4341 break; 4342 } 4343 4344 /* writing a new value is allowed only for 'STOPPED' pmcs */ 4345 if (pm->pm_state == PMC_STATE_RUNNING && 4346 (prw.pm_flags & PMC_F_NEWVALUE)) { 4347 error = EBUSY; 4348 break; 4349 } 4350 4351 if (PMC_IS_VIRTUAL_MODE(PMC_TO_MODE(pm))) { 4352 4353 /* 4354 * If this PMC is attached to its owner (i.e., 4355 * the process requesting this operation) and 4356 * is running, then attempt to get an 4357 * upto-date reading from hardware for a READ. 4358 * Writes are only allowed when the PMC is 4359 * stopped, so only update the saved value 4360 * field. 4361 * 4362 * If the PMC is not running, or is not 4363 * attached to its owner, read/write to the 4364 * savedvalue field. 4365 */ 4366 4367 ri = PMC_TO_ROWINDEX(pm); 4368 pcd = pmc_ri_to_classdep(md, ri, &adjri); 4369 4370 mtx_pool_lock_spin(pmc_mtxpool, pm); 4371 cpu = curthread->td_oncpu; 4372 4373 if (prw.pm_flags & PMC_F_OLDVALUE) { 4374 if ((pm->pm_flags & PMC_F_ATTACHED_TO_OWNER) && 4375 (pm->pm_state == PMC_STATE_RUNNING)) 4376 error = (*pcd->pcd_read_pmc)(cpu, adjri, 4377 &oldvalue); 4378 else 4379 oldvalue = pm->pm_gv.pm_savedvalue; 4380 } 4381 if (prw.pm_flags & PMC_F_NEWVALUE) 4382 pm->pm_gv.pm_savedvalue = prw.pm_value; 4383 4384 mtx_pool_unlock_spin(pmc_mtxpool, pm); 4385 4386 } else { /* System mode PMCs */ 4387 cpu = PMC_TO_CPU(pm); 4388 ri = PMC_TO_ROWINDEX(pm); 4389 pcd = pmc_ri_to_classdep(md, ri, &adjri); 4390 4391 if (!pmc_cpu_is_active(cpu)) { 4392 error = ENXIO; 4393 break; 4394 } 4395 4396 /* move this thread to CPU 'cpu' */ 4397 pmc_save_cpu_binding(&pb); 4398 pmc_select_cpu(cpu); 4399 4400 critical_enter(); 4401 /* save old value */ 4402 if (prw.pm_flags & PMC_F_OLDVALUE) 4403 if ((error = (*pcd->pcd_read_pmc)(cpu, adjri, 4404 &oldvalue))) 4405 goto error; 4406 /* write out new value */ 4407 if (prw.pm_flags & PMC_F_NEWVALUE) 4408 error = (*pcd->pcd_write_pmc)(cpu, adjri, 4409 prw.pm_value); 4410 error: 4411 critical_exit(); 4412 pmc_restore_cpu_binding(&pb); 4413 if (error) 4414 break; 4415 } 4416 4417 pprw = (struct pmc_op_pmcrw *) arg; 4418 4419 #ifdef HWPMC_DEBUG 4420 if (prw.pm_flags & PMC_F_NEWVALUE) 4421 PMCDBG3(PMC,OPS,2, "rw id=%d new %jx -> old %jx", 4422 ri, prw.pm_value, oldvalue); 4423 else if (prw.pm_flags & PMC_F_OLDVALUE) 4424 PMCDBG2(PMC,OPS,2, "rw id=%d -> old %jx", ri, oldvalue); 4425 #endif 4426 4427 /* return old value if requested */ 4428 if (prw.pm_flags & PMC_F_OLDVALUE) 4429 if ((error = copyout(&oldvalue, &pprw->pm_value, 4430 sizeof(prw.pm_value)))) 4431 break; 4432 4433 } 4434 break; 4435 4436 4437 /* 4438 * Set the sampling rate for a sampling mode PMC and the 4439 * initial count for a counting mode PMC. 4440 */ 4441 4442 case PMC_OP_PMCSETCOUNT: 4443 { 4444 struct pmc *pm; 4445 struct pmc_op_pmcsetcount sc; 4446 4447 PMC_DOWNGRADE_SX(); 4448 4449 if ((error = copyin(arg, &sc, sizeof(sc))) != 0) 4450 break; 4451 4452 if ((error = pmc_find_pmc(sc.pm_pmcid, &pm)) != 0) 4453 break; 4454 4455 if (pm->pm_state == PMC_STATE_RUNNING) { 4456 error = EBUSY; 4457 break; 4458 } 4459 4460 if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm))) 4461 pm->pm_sc.pm_reloadcount = sc.pm_count; 4462 else 4463 pm->pm_sc.pm_initial = sc.pm_count; 4464 } 4465 break; 4466 4467 4468 /* 4469 * Start a PMC. 4470 */ 4471 4472 case PMC_OP_PMCSTART: 4473 { 4474 pmc_id_t pmcid; 4475 struct pmc *pm; 4476 struct pmc_op_simple sp; 4477 4478 sx_assert(&pmc_sx, SX_XLOCKED); 4479 4480 if ((error = copyin(arg, &sp, sizeof(sp))) != 0) 4481 break; 4482 4483 pmcid = sp.pm_pmcid; 4484 4485 if ((error = pmc_find_pmc(pmcid, &pm)) != 0) 4486 break; 4487 4488 KASSERT(pmcid == pm->pm_id, 4489 ("[pmc,%d] pmcid %x != id %x", __LINE__, 4490 pm->pm_id, pmcid)); 4491 4492 if (pm->pm_state == PMC_STATE_RUNNING) /* already running */ 4493 break; 4494 else if (pm->pm_state != PMC_STATE_STOPPED && 4495 pm->pm_state != PMC_STATE_ALLOCATED) { 4496 error = EINVAL; 4497 break; 4498 } 4499 4500 error = pmc_start(pm); 4501 } 4502 break; 4503 4504 4505 /* 4506 * Stop a PMC. 4507 */ 4508 4509 case PMC_OP_PMCSTOP: 4510 { 4511 pmc_id_t pmcid; 4512 struct pmc *pm; 4513 struct pmc_op_simple sp; 4514 4515 PMC_DOWNGRADE_SX(); 4516 4517 if ((error = copyin(arg, &sp, sizeof(sp))) != 0) 4518 break; 4519 4520 pmcid = sp.pm_pmcid; 4521 4522 /* 4523 * Mark the PMC as inactive and invoke the MD stop 4524 * routines if needed. 4525 */ 4526 4527 if ((error = pmc_find_pmc(pmcid, &pm)) != 0) 4528 break; 4529 4530 KASSERT(pmcid == pm->pm_id, 4531 ("[pmc,%d] pmc id %x != pmcid %x", __LINE__, 4532 pm->pm_id, pmcid)); 4533 4534 if (pm->pm_state == PMC_STATE_STOPPED) /* already stopped */ 4535 break; 4536 else if (pm->pm_state != PMC_STATE_RUNNING) { 4537 error = EINVAL; 4538 break; 4539 } 4540 4541 error = pmc_stop(pm); 4542 } 4543 break; 4544 4545 4546 /* 4547 * Write a user supplied value to the log file. 4548 */ 4549 4550 case PMC_OP_WRITELOG: 4551 { 4552 struct pmc_op_writelog wl; 4553 struct pmc_owner *po; 4554 4555 PMC_DOWNGRADE_SX(); 4556 4557 if ((error = copyin(arg, &wl, sizeof(wl))) != 0) 4558 break; 4559 4560 if ((po = pmc_find_owner_descriptor(td->td_proc)) == NULL) { 4561 error = EINVAL; 4562 break; 4563 } 4564 4565 if ((po->po_flags & PMC_PO_OWNS_LOGFILE) == 0) { 4566 error = EINVAL; 4567 break; 4568 } 4569 4570 error = pmclog_process_userlog(po, &wl); 4571 } 4572 break; 4573 4574 4575 default: 4576 error = EINVAL; 4577 break; 4578 } 4579 4580 if (is_sx_downgraded) 4581 sx_sunlock(&pmc_sx); 4582 else 4583 sx_xunlock(&pmc_sx); 4584 done_syscall: 4585 if (error) 4586 counter_u64_add(pmc_stats.pm_syscall_errors, 1); 4587 4588 return (error); 4589 } 4590 4591 /* 4592 * Helper functions 4593 */ 4594 4595 4596 /* 4597 * Mark the thread as needing callchain capture and post an AST. The 4598 * actual callchain capture will be done in a context where it is safe 4599 * to take page faults. 4600 */ 4601 4602 static void 4603 pmc_post_callchain_callback(void) 4604 { 4605 struct thread *td; 4606 4607 td = curthread; 4608 4609 /* 4610 * If there is multiple PMCs for the same interrupt ignore new post 4611 */ 4612 if (td->td_pflags & TDP_CALLCHAIN) 4613 return; 4614 4615 /* 4616 * Mark this thread as needing callchain capture. 4617 * `td->td_pflags' will be safe to touch because this thread 4618 * was in user space when it was interrupted. 4619 */ 4620 td->td_pflags |= TDP_CALLCHAIN; 4621 4622 /* 4623 * Don't let this thread migrate between CPUs until callchain 4624 * capture completes. 4625 */ 4626 sched_pin(); 4627 4628 return; 4629 } 4630 4631 /* 4632 * Find a free slot in the per-cpu array of samples and capture the 4633 * current callchain there. If a sample was successfully added, a bit 4634 * is set in mask 'pmc_cpumask' denoting that the DO_SAMPLES hook 4635 * needs to be invoked from the clock handler. 4636 * 4637 * This function is meant to be called from an NMI handler. It cannot 4638 * use any of the locking primitives supplied by the OS. 4639 */ 4640 4641 static int 4642 pmc_add_sample(int ring, struct pmc *pm, struct trapframe *tf) 4643 { 4644 int error, cpu, callchaindepth, inuserspace; 4645 struct thread *td; 4646 struct pmc_sample *ps; 4647 struct pmc_samplebuffer *psb; 4648 4649 error = 0; 4650 4651 /* 4652 * Allocate space for a sample buffer. 4653 */ 4654 cpu = curcpu; 4655 psb = pmc_pcpu[cpu]->pc_sb[ring]; 4656 inuserspace = TRAPF_USERMODE(tf); 4657 ps = psb->ps_write; 4658 if (ps->ps_nsamples == PMC_SAMPLE_INUSE) { 4659 counter_u64_add(ps->ps_pmc->pm_runcount, -1); 4660 counter_u64_add(pmc_stats.pm_overwrites, 1); 4661 ps->ps_nsamples = 0; 4662 } else if (ps->ps_nsamples) { /* in use, reader hasn't caught up */ 4663 pm->pm_pcpu_state[cpu].pps_stalled = 1; 4664 counter_u64_add(pmc_stats.pm_intr_bufferfull, 1); 4665 PMCDBG6(SAM,INT,1,"(spc) cpu=%d pm=%p tf=%p um=%d wr=%d rd=%d", 4666 cpu, pm, (void *) tf, inuserspace, 4667 (int) (psb->ps_write - psb->ps_samples), 4668 (int) (psb->ps_read - psb->ps_samples)); 4669 callchaindepth = 1; 4670 error = ENOMEM; 4671 goto done; 4672 } 4673 4674 /* Fill in entry. */ 4675 PMCDBG6(SAM,INT,1,"cpu=%d pm=%p tf=%p um=%d wr=%d rd=%d", cpu, pm, 4676 (void *) tf, inuserspace, 4677 (int) (psb->ps_write - psb->ps_samples), 4678 (int) (psb->ps_read - psb->ps_samples)); 4679 4680 KASSERT(counter_u64_fetch(pm->pm_runcount) >= 0, 4681 ("[pmc,%d] pm=%p runcount %ld", __LINE__, (void *) pm, 4682 (unsigned long)counter_u64_fetch(pm->pm_runcount))); 4683 4684 counter_u64_add(pm->pm_runcount, 1); /* hold onto PMC */ 4685 4686 td = curthread; 4687 ps->ps_pmc = pm; 4688 ps->ps_td = td; 4689 ps->ps_pid = td->td_proc->p_pid; 4690 ps->ps_tid = td->td_tid; 4691 ps->ps_tsc = pmc_rdtsc(); 4692 4693 ps->ps_cpu = cpu; 4694 ps->ps_flags = inuserspace ? PMC_CC_F_USERSPACE : 0; 4695 4696 callchaindepth = (pm->pm_flags & PMC_F_CALLCHAIN) ? 4697 pmc_callchaindepth : 1; 4698 4699 if (callchaindepth == 1) 4700 ps->ps_pc[0] = PMC_TRAPFRAME_TO_PC(tf); 4701 else { 4702 /* 4703 * Kernel stack traversals can be done immediately, 4704 * while we defer to an AST for user space traversals. 4705 */ 4706 if (!inuserspace) { 4707 callchaindepth = 4708 pmc_save_kernel_callchain(ps->ps_pc, 4709 callchaindepth, tf); 4710 } else { 4711 pmc_post_callchain_callback(); 4712 callchaindepth = PMC_SAMPLE_INUSE; 4713 } 4714 } 4715 4716 ps->ps_nsamples = callchaindepth; /* mark entry as in use */ 4717 if (ring == PMC_UR) { 4718 ps->ps_nsamples_actual = callchaindepth; /* mark entry as in use */ 4719 ps->ps_nsamples = PMC_SAMPLE_INUSE; 4720 } else 4721 ps->ps_nsamples = callchaindepth; /* mark entry as in use */ 4722 /* increment write pointer, modulo ring buffer size */ 4723 ps++; 4724 if (ps == psb->ps_fence) 4725 psb->ps_write = psb->ps_samples; 4726 else 4727 psb->ps_write = ps; 4728 4729 done: 4730 /* mark CPU as needing processing */ 4731 if (callchaindepth != PMC_SAMPLE_INUSE) 4732 DPCPU_SET(pmc_sampled, 1); 4733 4734 return (error); 4735 } 4736 4737 /* 4738 * Interrupt processing. 4739 * 4740 * This function is meant to be called from an NMI handler. It cannot 4741 * use any of the locking primitives supplied by the OS. 4742 */ 4743 4744 int 4745 pmc_process_interrupt(int ring, struct pmc *pm, struct trapframe *tf) 4746 { 4747 struct thread *td; 4748 4749 td = curthread; 4750 if ((pm->pm_flags & PMC_F_USERCALLCHAIN) && 4751 (td->td_proc->p_flag & P_KPROC) == 0 && 4752 !TRAPF_USERMODE(tf)) { 4753 atomic_add_int(&td->td_pmcpend, 1); 4754 return (pmc_add_sample(PMC_UR, pm, tf)); 4755 } 4756 return (pmc_add_sample(ring, pm, tf)); 4757 } 4758 4759 /* 4760 * Capture a user call chain. This function will be called from ast() 4761 * before control returns to userland and before the process gets 4762 * rescheduled. 4763 */ 4764 4765 static void 4766 pmc_capture_user_callchain(int cpu, int ring, struct trapframe *tf) 4767 { 4768 struct pmc *pm; 4769 struct thread *td; 4770 struct pmc_sample *ps, *ps_end; 4771 struct pmc_samplebuffer *psb; 4772 int nsamples, nrecords, pass; 4773 #ifdef INVARIANTS 4774 int ncallchains; 4775 int nfree; 4776 #endif 4777 4778 psb = pmc_pcpu[cpu]->pc_sb[ring]; 4779 td = curthread; 4780 4781 KASSERT(td->td_pflags & TDP_CALLCHAIN, 4782 ("[pmc,%d] Retrieving callchain for thread that doesn't want it", 4783 __LINE__)); 4784 4785 #ifdef INVARIANTS 4786 ncallchains = 0; 4787 nfree = 0; 4788 #endif 4789 nrecords = INT_MAX; 4790 pass = 0; 4791 restart: 4792 if (ring == PMC_UR) 4793 nrecords = atomic_readandclear_32(&td->td_pmcpend); 4794 4795 /* 4796 * Iterate through all deferred callchain requests. 4797 * Walk from the current read pointer to the current 4798 * write pointer. 4799 */ 4800 4801 ps = psb->ps_read; 4802 ps_end = psb->ps_write; 4803 do { 4804 #ifdef INVARIANTS 4805 if (ps->ps_nsamples == PMC_SAMPLE_FREE) { 4806 nfree++; 4807 goto next; 4808 } 4809 4810 if ((ps->ps_pmc == NULL) || 4811 (ps->ps_pmc->pm_state != PMC_STATE_RUNNING)) 4812 nfree++; 4813 #endif 4814 if (ps->ps_nsamples != PMC_SAMPLE_INUSE) 4815 goto next; 4816 if (ps->ps_td != td) 4817 goto next; 4818 4819 KASSERT(ps->ps_cpu == cpu, 4820 ("[pmc,%d] cpu mismatch ps_cpu=%d pcpu=%d", __LINE__, 4821 ps->ps_cpu, PCPU_GET(cpuid))); 4822 4823 pm = ps->ps_pmc; 4824 4825 KASSERT(pm->pm_flags & PMC_F_CALLCHAIN, 4826 ("[pmc,%d] Retrieving callchain for PMC that doesn't " 4827 "want it", __LINE__)); 4828 4829 KASSERT(counter_u64_fetch(pm->pm_runcount) > 0, 4830 ("[pmc,%d] runcount %ld", __LINE__, (unsigned long)counter_u64_fetch(pm->pm_runcount))); 4831 4832 if (ring == PMC_UR) { 4833 nsamples = ps->ps_nsamples_actual; 4834 counter_u64_add(pmc_stats.pm_merges, 1); 4835 } else 4836 nsamples = 0; 4837 4838 /* 4839 * Retrieve the callchain and mark the sample buffer 4840 * as 'processable' by the timer tick sweep code. 4841 */ 4842 4843 #ifdef INVARIANTS 4844 ncallchains++; 4845 #endif 4846 4847 if (__predict_true(nsamples < pmc_callchaindepth - 1)) 4848 nsamples += pmc_save_user_callchain(ps->ps_pc + nsamples, 4849 pmc_callchaindepth - nsamples - 1, tf); 4850 wmb(); 4851 ps->ps_nsamples = nsamples; 4852 if (nrecords-- == 1) 4853 break; 4854 next: 4855 /* increment the pointer, modulo sample ring size */ 4856 if (++ps == psb->ps_fence) 4857 ps = psb->ps_samples; 4858 } while (ps != ps_end); 4859 if (__predict_false(ring == PMC_UR && td->td_pmcpend)) { 4860 if (pass == 0) { 4861 pass = 1; 4862 goto restart; 4863 } 4864 /* only collect samples for this part once */ 4865 td->td_pmcpend = 0; 4866 } 4867 4868 #ifdef INVARIANTS 4869 if (ring == PMC_HR) 4870 KASSERT(ncallchains > 0 || nfree > 0, 4871 ("[pmc,%d] cpu %d didn't find a sample to collect", __LINE__, 4872 cpu)); 4873 #endif 4874 4875 /* mark CPU as needing processing */ 4876 DPCPU_SET(pmc_sampled, 1); 4877 } 4878 4879 4880 static void 4881 pmc_flush_ring(int cpu, int ring) 4882 { 4883 struct pmc *pm; 4884 struct pmc_sample *ps; 4885 struct pmc_samplebuffer *psb; 4886 int n; 4887 4888 psb = pmc_pcpu[cpu]->pc_sb[ring]; 4889 4890 for (n = 0; n < pmc_nsamples; n++) { /* bound on #iterations */ 4891 4892 ps = psb->ps_read; 4893 if (ps->ps_nsamples == PMC_SAMPLE_FREE) 4894 goto next; 4895 pm = ps->ps_pmc; 4896 counter_u64_add(pm->pm_runcount, -1); 4897 ps->ps_nsamples = PMC_SAMPLE_FREE; 4898 /* increment read pointer, modulo sample size */ 4899 next: 4900 if (++ps == psb->ps_fence) 4901 psb->ps_read = psb->ps_samples; 4902 else 4903 psb->ps_read = ps; 4904 } 4905 } 4906 4907 void 4908 pmc_flush_samples(int cpu) 4909 { 4910 int n; 4911 4912 for (n = 0; n < PMC_NUM_SR; n++) 4913 pmc_flush_ring(cpu, n); 4914 } 4915 4916 4917 /* 4918 * Process saved PC samples. 4919 */ 4920 4921 static void 4922 pmc_process_samples(int cpu, int ring) 4923 { 4924 struct pmc *pm; 4925 int adjri, n; 4926 struct thread *td; 4927 struct pmc_owner *po; 4928 struct pmc_sample *ps; 4929 struct pmc_classdep *pcd; 4930 struct pmc_samplebuffer *psb; 4931 4932 KASSERT(PCPU_GET(cpuid) == cpu, 4933 ("[pmc,%d] not on the correct CPU pcpu=%d cpu=%d", __LINE__, 4934 PCPU_GET(cpuid), cpu)); 4935 4936 psb = pmc_pcpu[cpu]->pc_sb[ring]; 4937 4938 for (n = 0; n < pmc_nsamples; n++) { /* bound on #iterations */ 4939 4940 ps = psb->ps_read; 4941 if (ps->ps_nsamples == PMC_SAMPLE_FREE) 4942 break; 4943 4944 pm = ps->ps_pmc; 4945 4946 KASSERT(counter_u64_fetch(pm->pm_runcount) > 0, 4947 ("[pmc,%d] pm=%p runcount %ld", __LINE__, (void *) pm, 4948 (unsigned long)counter_u64_fetch(pm->pm_runcount))); 4949 4950 po = pm->pm_owner; 4951 4952 KASSERT(PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)), 4953 ("[pmc,%d] pmc=%p non-sampling mode=%d", __LINE__, 4954 pm, PMC_TO_MODE(pm))); 4955 4956 /* Ignore PMCs that have been switched off */ 4957 if (pm->pm_state != PMC_STATE_RUNNING) 4958 goto entrydone; 4959 4960 /* If there is a pending AST wait for completion */ 4961 if (ps->ps_nsamples == PMC_SAMPLE_INUSE) { 4962 /* Need a rescan at a later time. */ 4963 DPCPU_SET(pmc_sampled, 1); 4964 break; 4965 } 4966 4967 PMCDBG6(SAM,OPS,1,"cpu=%d pm=%p n=%d fl=%x wr=%d rd=%d", cpu, 4968 pm, ps->ps_nsamples, ps->ps_flags, 4969 (int) (psb->ps_write - psb->ps_samples), 4970 (int) (psb->ps_read - psb->ps_samples)); 4971 4972 /* 4973 * If this is a process-mode PMC that is attached to 4974 * its owner, and if the PC is in user mode, update 4975 * profiling statistics like timer-based profiling 4976 * would have done. 4977 * 4978 * Otherwise, this is either a sampling-mode PMC that 4979 * is attached to a different process than its owner, 4980 * or a system-wide sampling PMC. Dispatch a log 4981 * entry to the PMC's owner process. 4982 */ 4983 if (pm->pm_flags & PMC_F_ATTACHED_TO_OWNER) { 4984 if (ps->ps_flags & PMC_CC_F_USERSPACE) { 4985 td = FIRST_THREAD_IN_PROC(po->po_owner); 4986 addupc_intr(td, ps->ps_pc[0], 1); 4987 } 4988 } else 4989 pmclog_process_callchain(pm, ps); 4990 4991 entrydone: 4992 ps->ps_nsamples = 0; /* mark entry as free */ 4993 counter_u64_add(pm->pm_runcount, -1); 4994 4995 /* increment read pointer, modulo sample size */ 4996 if (++ps == psb->ps_fence) 4997 psb->ps_read = psb->ps_samples; 4998 else 4999 psb->ps_read = ps; 5000 } 5001 5002 counter_u64_add(pmc_stats.pm_log_sweeps, 1); 5003 5004 /* Do not re-enable stalled PMCs if we failed to process any samples */ 5005 if (n == 0) 5006 return; 5007 5008 /* 5009 * Restart any stalled sampling PMCs on this CPU. 5010 * 5011 * If the NMI handler sets the pm_stalled field of a PMC after 5012 * the check below, we'll end up processing the stalled PMC at 5013 * the next hardclock tick. 5014 */ 5015 for (n = 0; n < md->pmd_npmc; n++) { 5016 pcd = pmc_ri_to_classdep(md, n, &adjri); 5017 KASSERT(pcd != NULL, 5018 ("[pmc,%d] null pcd ri=%d", __LINE__, n)); 5019 (void) (*pcd->pcd_get_config)(cpu,adjri,&pm); 5020 5021 if (pm == NULL || /* !cfg'ed */ 5022 pm->pm_state != PMC_STATE_RUNNING || /* !active */ 5023 !PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)) || /* !sampling */ 5024 !pm->pm_pcpu_state[cpu].pps_cpustate || /* !desired */ 5025 !pm->pm_pcpu_state[cpu].pps_stalled) /* !stalled */ 5026 continue; 5027 5028 pm->pm_pcpu_state[cpu].pps_stalled = 0; 5029 (*pcd->pcd_start_pmc)(cpu, adjri); 5030 } 5031 } 5032 5033 /* 5034 * Event handlers. 5035 */ 5036 5037 /* 5038 * Handle a process exit. 5039 * 5040 * Remove this process from all hash tables. If this process 5041 * owned any PMCs, turn off those PMCs and deallocate them, 5042 * removing any associations with target processes. 5043 * 5044 * This function will be called by the last 'thread' of a 5045 * process. 5046 * 5047 * XXX This eventhandler gets called early in the exit process. 5048 * Consider using a 'hook' invocation from thread_exit() or equivalent 5049 * spot. Another negative is that kse_exit doesn't seem to call 5050 * exit1() [??]. 5051 * 5052 */ 5053 5054 static void 5055 pmc_process_exit(void *arg __unused, struct proc *p) 5056 { 5057 struct pmc *pm; 5058 int adjri, cpu; 5059 unsigned int ri; 5060 int is_using_hwpmcs; 5061 struct pmc_owner *po; 5062 struct pmc_process *pp; 5063 struct pmc_classdep *pcd; 5064 pmc_value_t newvalue, tmp; 5065 5066 PROC_LOCK(p); 5067 is_using_hwpmcs = p->p_flag & P_HWPMC; 5068 PROC_UNLOCK(p); 5069 5070 /* 5071 * Log a sysexit event to all SS PMC owners. 5072 */ 5073 epoch_enter_preempt(global_epoch_preempt); 5074 CK_LIST_FOREACH(po, &pmc_ss_owners, po_ssnext) 5075 if (po->po_flags & PMC_PO_OWNS_LOGFILE) 5076 pmclog_process_sysexit(po, p->p_pid); 5077 epoch_exit_preempt(global_epoch_preempt); 5078 5079 if (!is_using_hwpmcs) 5080 return; 5081 5082 PMC_GET_SX_XLOCK(); 5083 PMCDBG3(PRC,EXT,1,"process-exit proc=%p (%d, %s)", p, p->p_pid, 5084 p->p_comm); 5085 5086 /* 5087 * Since this code is invoked by the last thread in an exiting 5088 * process, we would have context switched IN at some prior 5089 * point. However, with PREEMPTION, kernel mode context 5090 * switches may happen any time, so we want to disable a 5091 * context switch OUT till we get any PMCs targeting this 5092 * process off the hardware. 5093 * 5094 * We also need to atomically remove this process' 5095 * entry from our target process hash table, using 5096 * PMC_FLAG_REMOVE. 5097 */ 5098 PMCDBG3(PRC,EXT,1, "process-exit proc=%p (%d, %s)", p, p->p_pid, 5099 p->p_comm); 5100 5101 critical_enter(); /* no preemption */ 5102 5103 cpu = curthread->td_oncpu; 5104 5105 if ((pp = pmc_find_process_descriptor(p, 5106 PMC_FLAG_REMOVE)) != NULL) { 5107 5108 PMCDBG2(PRC,EXT,2, 5109 "process-exit proc=%p pmc-process=%p", p, pp); 5110 5111 /* 5112 * The exiting process could the target of 5113 * some PMCs which will be running on 5114 * currently executing CPU. 5115 * 5116 * We need to turn these PMCs off like we 5117 * would do at context switch OUT time. 5118 */ 5119 for (ri = 0; ri < md->pmd_npmc; ri++) { 5120 5121 /* 5122 * Pick up the pmc pointer from hardware 5123 * state similar to the CSW_OUT code. 5124 */ 5125 pm = NULL; 5126 5127 pcd = pmc_ri_to_classdep(md, ri, &adjri); 5128 5129 (void) (*pcd->pcd_get_config)(cpu, adjri, &pm); 5130 5131 PMCDBG2(PRC,EXT,2, "ri=%d pm=%p", ri, pm); 5132 5133 if (pm == NULL || 5134 !PMC_IS_VIRTUAL_MODE(PMC_TO_MODE(pm))) 5135 continue; 5136 5137 PMCDBG4(PRC,EXT,2, "ppmcs[%d]=%p pm=%p " 5138 "state=%d", ri, pp->pp_pmcs[ri].pp_pmc, 5139 pm, pm->pm_state); 5140 5141 KASSERT(PMC_TO_ROWINDEX(pm) == ri, 5142 ("[pmc,%d] ri mismatch pmc(%d) ri(%d)", 5143 __LINE__, PMC_TO_ROWINDEX(pm), ri)); 5144 5145 KASSERT(pm == pp->pp_pmcs[ri].pp_pmc, 5146 ("[pmc,%d] pm %p != pp_pmcs[%d] %p", 5147 __LINE__, pm, ri, pp->pp_pmcs[ri].pp_pmc)); 5148 5149 KASSERT(counter_u64_fetch(pm->pm_runcount) > 0, 5150 ("[pmc,%d] bad runcount ri %d rc %ld", 5151 __LINE__, ri, (unsigned long)counter_u64_fetch(pm->pm_runcount))); 5152 5153 /* 5154 * Change desired state, and then stop if not 5155 * stalled. This two-step dance should avoid 5156 * race conditions where an interrupt re-enables 5157 * the PMC after this code has already checked 5158 * the pm_stalled flag. 5159 */ 5160 if (pm->pm_pcpu_state[cpu].pps_cpustate) { 5161 pm->pm_pcpu_state[cpu].pps_cpustate = 0; 5162 if (!pm->pm_pcpu_state[cpu].pps_stalled) { 5163 (void) pcd->pcd_stop_pmc(cpu, adjri); 5164 5165 if (PMC_TO_MODE(pm) == PMC_MODE_TC) { 5166 pcd->pcd_read_pmc(cpu, adjri, 5167 &newvalue); 5168 tmp = newvalue - 5169 PMC_PCPU_SAVED(cpu,ri); 5170 5171 mtx_pool_lock_spin(pmc_mtxpool, 5172 pm); 5173 pm->pm_gv.pm_savedvalue += tmp; 5174 pp->pp_pmcs[ri].pp_pmcval += 5175 tmp; 5176 mtx_pool_unlock_spin( 5177 pmc_mtxpool, pm); 5178 } 5179 } 5180 } 5181 5182 counter_u64_add(pm->pm_runcount, -1); 5183 5184 KASSERT((int) counter_u64_fetch(pm->pm_runcount) >= 0, 5185 ("[pmc,%d] runcount is %d", __LINE__, ri)); 5186 5187 (void) pcd->pcd_config_pmc(cpu, adjri, NULL); 5188 } 5189 5190 /* 5191 * Inform the MD layer of this pseudo "context switch 5192 * out" 5193 */ 5194 (void) md->pmd_switch_out(pmc_pcpu[cpu], pp); 5195 5196 critical_exit(); /* ok to be pre-empted now */ 5197 5198 /* 5199 * Unlink this process from the PMCs that are 5200 * targeting it. This will send a signal to 5201 * all PMC owner's whose PMCs are orphaned. 5202 * 5203 * Log PMC value at exit time if requested. 5204 */ 5205 for (ri = 0; ri < md->pmd_npmc; ri++) 5206 if ((pm = pp->pp_pmcs[ri].pp_pmc) != NULL) { 5207 if (pm->pm_flags & PMC_F_NEEDS_LOGFILE && 5208 PMC_IS_COUNTING_MODE(PMC_TO_MODE(pm))) 5209 pmclog_process_procexit(pm, pp); 5210 pmc_unlink_target_process(pm, pp); 5211 } 5212 free(pp, M_PMC); 5213 5214 } else 5215 critical_exit(); /* pp == NULL */ 5216 5217 5218 /* 5219 * If the process owned PMCs, free them up and free up 5220 * memory. 5221 */ 5222 if ((po = pmc_find_owner_descriptor(p)) != NULL) { 5223 pmc_remove_owner(po); 5224 pmc_destroy_owner_descriptor(po); 5225 } 5226 5227 sx_xunlock(&pmc_sx); 5228 } 5229 5230 /* 5231 * Handle a process fork. 5232 * 5233 * If the parent process 'p1' is under HWPMC monitoring, then copy 5234 * over any attached PMCs that have 'do_descendants' semantics. 5235 */ 5236 5237 static void 5238 pmc_process_fork(void *arg __unused, struct proc *p1, struct proc *newproc, 5239 int flags) 5240 { 5241 int is_using_hwpmcs; 5242 unsigned int ri; 5243 uint32_t do_descendants; 5244 struct pmc *pm; 5245 struct pmc_owner *po; 5246 struct pmc_process *ppnew, *ppold; 5247 5248 (void) flags; /* unused parameter */ 5249 5250 PROC_LOCK(p1); 5251 is_using_hwpmcs = p1->p_flag & P_HWPMC; 5252 PROC_UNLOCK(p1); 5253 5254 /* 5255 * If there are system-wide sampling PMCs active, we need to 5256 * log all fork events to their owner's logs. 5257 */ 5258 epoch_enter_preempt(global_epoch_preempt); 5259 CK_LIST_FOREACH(po, &pmc_ss_owners, po_ssnext) 5260 if (po->po_flags & PMC_PO_OWNS_LOGFILE) { 5261 pmclog_process_procfork(po, p1->p_pid, newproc->p_pid); 5262 pmclog_process_proccreate(po, newproc, 1); 5263 } 5264 epoch_exit_preempt(global_epoch_preempt); 5265 5266 if (!is_using_hwpmcs) 5267 return; 5268 5269 PMC_GET_SX_XLOCK(); 5270 PMCDBG4(PMC,FRK,1, "process-fork proc=%p (%d, %s) -> %p", p1, 5271 p1->p_pid, p1->p_comm, newproc); 5272 5273 /* 5274 * If the parent process (curthread->td_proc) is a 5275 * target of any PMCs, look for PMCs that are to be 5276 * inherited, and link these into the new process 5277 * descriptor. 5278 */ 5279 if ((ppold = pmc_find_process_descriptor(curthread->td_proc, 5280 PMC_FLAG_NONE)) == NULL) 5281 goto done; /* nothing to do */ 5282 5283 do_descendants = 0; 5284 for (ri = 0; ri < md->pmd_npmc; ri++) 5285 if ((pm = ppold->pp_pmcs[ri].pp_pmc) != NULL) 5286 do_descendants |= pm->pm_flags & PMC_F_DESCENDANTS; 5287 if (do_descendants == 0) /* nothing to do */ 5288 goto done; 5289 5290 /* 5291 * Now mark the new process as being tracked by this driver. 5292 */ 5293 PROC_LOCK(newproc); 5294 newproc->p_flag |= P_HWPMC; 5295 PROC_UNLOCK(newproc); 5296 5297 /* allocate a descriptor for the new process */ 5298 if ((ppnew = pmc_find_process_descriptor(newproc, 5299 PMC_FLAG_ALLOCATE)) == NULL) 5300 goto done; 5301 5302 /* 5303 * Run through all PMCs that were targeting the old process 5304 * and which specified F_DESCENDANTS and attach them to the 5305 * new process. 5306 * 5307 * Log the fork event to all owners of PMCs attached to this 5308 * process, if not already logged. 5309 */ 5310 for (ri = 0; ri < md->pmd_npmc; ri++) 5311 if ((pm = ppold->pp_pmcs[ri].pp_pmc) != NULL && 5312 (pm->pm_flags & PMC_F_DESCENDANTS)) { 5313 pmc_link_target_process(pm, ppnew); 5314 po = pm->pm_owner; 5315 if (po->po_sscount == 0 && 5316 po->po_flags & PMC_PO_OWNS_LOGFILE) 5317 pmclog_process_procfork(po, p1->p_pid, 5318 newproc->p_pid); 5319 } 5320 5321 done: 5322 sx_xunlock(&pmc_sx); 5323 } 5324 5325 static void 5326 pmc_process_threadcreate(struct thread *td) 5327 { 5328 struct pmc_owner *po; 5329 5330 epoch_enter_preempt(global_epoch_preempt); 5331 CK_LIST_FOREACH(po, &pmc_ss_owners, po_ssnext) 5332 if (po->po_flags & PMC_PO_OWNS_LOGFILE) 5333 pmclog_process_threadcreate(po, td, 1); 5334 epoch_exit_preempt(global_epoch_preempt); 5335 } 5336 5337 static void 5338 pmc_process_threadexit(struct thread *td) 5339 { 5340 struct pmc_owner *po; 5341 5342 epoch_enter_preempt(global_epoch_preempt); 5343 CK_LIST_FOREACH(po, &pmc_ss_owners, po_ssnext) 5344 if (po->po_flags & PMC_PO_OWNS_LOGFILE) 5345 pmclog_process_threadexit(po, td); 5346 epoch_exit_preempt(global_epoch_preempt); 5347 } 5348 5349 static void 5350 pmc_process_proccreate(struct proc *p) 5351 { 5352 struct pmc_owner *po; 5353 5354 epoch_enter_preempt(global_epoch_preempt); 5355 CK_LIST_FOREACH(po, &pmc_ss_owners, po_ssnext) 5356 if (po->po_flags & PMC_PO_OWNS_LOGFILE) 5357 pmclog_process_proccreate(po, p, 1 /* sync */); 5358 epoch_exit_preempt(global_epoch_preempt); 5359 } 5360 5361 static void 5362 pmc_process_allproc(struct pmc *pm) 5363 { 5364 struct pmc_owner *po; 5365 struct thread *td; 5366 struct proc *p; 5367 5368 po = pm->pm_owner; 5369 if ((po->po_flags & PMC_PO_OWNS_LOGFILE) == 0) 5370 return; 5371 sx_slock(&allproc_lock); 5372 FOREACH_PROC_IN_SYSTEM(p) { 5373 pmclog_process_proccreate(po, p, 0 /* sync */); 5374 PROC_LOCK(p); 5375 FOREACH_THREAD_IN_PROC(p, td) 5376 pmclog_process_threadcreate(po, td, 0 /* sync */); 5377 PROC_UNLOCK(p); 5378 } 5379 sx_sunlock(&allproc_lock); 5380 pmclog_flush(po, 0); 5381 } 5382 5383 static void 5384 pmc_kld_load(void *arg __unused, linker_file_t lf) 5385 { 5386 struct pmc_owner *po; 5387 5388 /* 5389 * Notify owners of system sampling PMCs about KLD operations. 5390 */ 5391 epoch_enter_preempt(global_epoch_preempt); 5392 CK_LIST_FOREACH(po, &pmc_ss_owners, po_ssnext) 5393 if (po->po_flags & PMC_PO_OWNS_LOGFILE) 5394 pmclog_process_map_in(po, (pid_t) -1, 5395 (uintfptr_t) lf->address, lf->filename); 5396 epoch_exit_preempt(global_epoch_preempt); 5397 5398 /* 5399 * TODO: Notify owners of (all) process-sampling PMCs too. 5400 */ 5401 } 5402 5403 static void 5404 pmc_kld_unload(void *arg __unused, const char *filename __unused, 5405 caddr_t address, size_t size) 5406 { 5407 struct pmc_owner *po; 5408 5409 epoch_enter_preempt(global_epoch_preempt); 5410 CK_LIST_FOREACH(po, &pmc_ss_owners, po_ssnext) 5411 if (po->po_flags & PMC_PO_OWNS_LOGFILE) 5412 pmclog_process_map_out(po, (pid_t) -1, 5413 (uintfptr_t) address, (uintfptr_t) address + size); 5414 epoch_exit_preempt(global_epoch_preempt); 5415 5416 /* 5417 * TODO: Notify owners of process-sampling PMCs. 5418 */ 5419 } 5420 5421 /* 5422 * initialization 5423 */ 5424 static const char * 5425 pmc_name_of_pmcclass(enum pmc_class class) 5426 { 5427 5428 switch (class) { 5429 #undef __PMC_CLASS 5430 #define __PMC_CLASS(S,V,D) \ 5431 case PMC_CLASS_##S: \ 5432 return #S; 5433 __PMC_CLASSES(); 5434 default: 5435 return ("<unknown>"); 5436 } 5437 } 5438 5439 /* 5440 * Base class initializer: allocate structure and set default classes. 5441 */ 5442 struct pmc_mdep * 5443 pmc_mdep_alloc(int nclasses) 5444 { 5445 struct pmc_mdep *md; 5446 int n; 5447 5448 /* SOFT + md classes */ 5449 n = 1 + nclasses; 5450 md = malloc(sizeof(struct pmc_mdep) + n * 5451 sizeof(struct pmc_classdep), M_PMC, M_WAITOK|M_ZERO); 5452 md->pmd_nclass = n; 5453 5454 /* Add base class. */ 5455 pmc_soft_initialize(md); 5456 return md; 5457 } 5458 5459 void 5460 pmc_mdep_free(struct pmc_mdep *md) 5461 { 5462 pmc_soft_finalize(md); 5463 free(md, M_PMC); 5464 } 5465 5466 static int 5467 generic_switch_in(struct pmc_cpu *pc, struct pmc_process *pp) 5468 { 5469 (void) pc; (void) pp; 5470 5471 return (0); 5472 } 5473 5474 static int 5475 generic_switch_out(struct pmc_cpu *pc, struct pmc_process *pp) 5476 { 5477 (void) pc; (void) pp; 5478 5479 return (0); 5480 } 5481 5482 static struct pmc_mdep * 5483 pmc_generic_cpu_initialize(void) 5484 { 5485 struct pmc_mdep *md; 5486 5487 md = pmc_mdep_alloc(0); 5488 5489 md->pmd_cputype = PMC_CPU_GENERIC; 5490 5491 md->pmd_pcpu_init = NULL; 5492 md->pmd_pcpu_fini = NULL; 5493 md->pmd_switch_in = generic_switch_in; 5494 md->pmd_switch_out = generic_switch_out; 5495 5496 return (md); 5497 } 5498 5499 static void 5500 pmc_generic_cpu_finalize(struct pmc_mdep *md) 5501 { 5502 (void) md; 5503 } 5504 5505 5506 static int 5507 pmc_initialize(void) 5508 { 5509 int c, cpu, error, n, ri; 5510 unsigned int maxcpu, domain; 5511 struct pcpu *pc; 5512 struct pmc_binding pb; 5513 struct pmc_sample *ps; 5514 struct pmc_classdep *pcd; 5515 struct pmc_samplebuffer *sb; 5516 5517 md = NULL; 5518 error = 0; 5519 5520 pmc_stats.pm_intr_ignored = counter_u64_alloc(M_WAITOK); 5521 pmc_stats.pm_intr_processed = counter_u64_alloc(M_WAITOK); 5522 pmc_stats.pm_intr_bufferfull = counter_u64_alloc(M_WAITOK); 5523 pmc_stats.pm_syscalls = counter_u64_alloc(M_WAITOK); 5524 pmc_stats.pm_syscall_errors = counter_u64_alloc(M_WAITOK); 5525 pmc_stats.pm_buffer_requests = counter_u64_alloc(M_WAITOK); 5526 pmc_stats.pm_buffer_requests_failed = counter_u64_alloc(M_WAITOK); 5527 pmc_stats.pm_log_sweeps = counter_u64_alloc(M_WAITOK); 5528 pmc_stats.pm_merges = counter_u64_alloc(M_WAITOK); 5529 pmc_stats.pm_overwrites = counter_u64_alloc(M_WAITOK); 5530 5531 #ifdef HWPMC_DEBUG 5532 /* parse debug flags first */ 5533 if (TUNABLE_STR_FETCH(PMC_SYSCTL_NAME_PREFIX "debugflags", 5534 pmc_debugstr, sizeof(pmc_debugstr))) 5535 pmc_debugflags_parse(pmc_debugstr, 5536 pmc_debugstr+strlen(pmc_debugstr)); 5537 #endif 5538 5539 PMCDBG1(MOD,INI,0, "PMC Initialize (version %x)", PMC_VERSION); 5540 5541 /* check kernel version */ 5542 if (pmc_kernel_version != PMC_VERSION) { 5543 if (pmc_kernel_version == 0) 5544 printf("hwpmc: this kernel has not been compiled with " 5545 "'options HWPMC_HOOKS'.\n"); 5546 else 5547 printf("hwpmc: kernel version (0x%x) does not match " 5548 "module version (0x%x).\n", pmc_kernel_version, 5549 PMC_VERSION); 5550 return EPROGMISMATCH; 5551 } 5552 5553 /* 5554 * check sysctl parameters 5555 */ 5556 5557 if (pmc_hashsize <= 0) { 5558 (void) printf("hwpmc: tunable \"hashsize\"=%d must be " 5559 "greater than zero.\n", pmc_hashsize); 5560 pmc_hashsize = PMC_HASH_SIZE; 5561 } 5562 5563 if (pmc_nsamples <= 0 || pmc_nsamples > 65535) { 5564 (void) printf("hwpmc: tunable \"nsamples\"=%d out of " 5565 "range.\n", pmc_nsamples); 5566 pmc_nsamples = PMC_NSAMPLES; 5567 } 5568 5569 if (pmc_callchaindepth <= 0 || 5570 pmc_callchaindepth > PMC_CALLCHAIN_DEPTH_MAX) { 5571 (void) printf("hwpmc: tunable \"callchaindepth\"=%d out of " 5572 "range - using %d.\n", pmc_callchaindepth, 5573 PMC_CALLCHAIN_DEPTH_MAX); 5574 pmc_callchaindepth = PMC_CALLCHAIN_DEPTH_MAX; 5575 } 5576 5577 md = pmc_md_initialize(); 5578 if (md == NULL) { 5579 /* Default to generic CPU. */ 5580 md = pmc_generic_cpu_initialize(); 5581 if (md == NULL) 5582 return (ENOSYS); 5583 } 5584 5585 KASSERT(md->pmd_nclass >= 1 && md->pmd_npmc >= 1, 5586 ("[pmc,%d] no classes or pmcs", __LINE__)); 5587 5588 /* Compute the map from row-indices to classdep pointers. */ 5589 pmc_rowindex_to_classdep = malloc(sizeof(struct pmc_classdep *) * 5590 md->pmd_npmc, M_PMC, M_WAITOK|M_ZERO); 5591 5592 for (n = 0; n < md->pmd_npmc; n++) 5593 pmc_rowindex_to_classdep[n] = NULL; 5594 for (ri = c = 0; c < md->pmd_nclass; c++) { 5595 pcd = &md->pmd_classdep[c]; 5596 for (n = 0; n < pcd->pcd_num; n++, ri++) 5597 pmc_rowindex_to_classdep[ri] = pcd; 5598 } 5599 5600 KASSERT(ri == md->pmd_npmc, 5601 ("[pmc,%d] npmc miscomputed: ri=%d, md->npmc=%d", __LINE__, 5602 ri, md->pmd_npmc)); 5603 5604 maxcpu = pmc_cpu_max(); 5605 5606 /* allocate space for the per-cpu array */ 5607 pmc_pcpu = malloc(maxcpu * sizeof(struct pmc_cpu *), M_PMC, 5608 M_WAITOK|M_ZERO); 5609 5610 /* per-cpu 'saved values' for managing process-mode PMCs */ 5611 pmc_pcpu_saved = malloc(sizeof(pmc_value_t) * maxcpu * md->pmd_npmc, 5612 M_PMC, M_WAITOK); 5613 5614 /* Perform CPU-dependent initialization. */ 5615 pmc_save_cpu_binding(&pb); 5616 error = 0; 5617 for (cpu = 0; error == 0 && cpu < maxcpu; cpu++) { 5618 if (!pmc_cpu_is_active(cpu)) 5619 continue; 5620 pmc_select_cpu(cpu); 5621 pmc_pcpu[cpu] = malloc(sizeof(struct pmc_cpu) + 5622 md->pmd_npmc * sizeof(struct pmc_hw *), M_PMC, 5623 M_WAITOK|M_ZERO); 5624 if (md->pmd_pcpu_init) 5625 error = md->pmd_pcpu_init(md, cpu); 5626 for (n = 0; error == 0 && n < md->pmd_nclass; n++) 5627 error = md->pmd_classdep[n].pcd_pcpu_init(md, cpu); 5628 } 5629 pmc_restore_cpu_binding(&pb); 5630 5631 if (error) 5632 return (error); 5633 5634 /* allocate space for the sample array */ 5635 for (cpu = 0; cpu < maxcpu; cpu++) { 5636 if (!pmc_cpu_is_active(cpu)) 5637 continue; 5638 pc = pcpu_find(cpu); 5639 domain = pc->pc_domain; 5640 sb = malloc_domain(sizeof(struct pmc_samplebuffer) + 5641 pmc_nsamples * sizeof(struct pmc_sample), M_PMC, domain, 5642 M_WAITOK|M_ZERO); 5643 sb->ps_read = sb->ps_write = sb->ps_samples; 5644 sb->ps_fence = sb->ps_samples + pmc_nsamples; 5645 5646 KASSERT(pmc_pcpu[cpu] != NULL, 5647 ("[pmc,%d] cpu=%d Null per-cpu data", __LINE__, cpu)); 5648 5649 sb->ps_callchains = malloc_domain(pmc_callchaindepth * pmc_nsamples * 5650 sizeof(uintptr_t), M_PMC, domain, M_WAITOK|M_ZERO); 5651 5652 for (n = 0, ps = sb->ps_samples; n < pmc_nsamples; n++, ps++) 5653 ps->ps_pc = sb->ps_callchains + 5654 (n * pmc_callchaindepth); 5655 5656 pmc_pcpu[cpu]->pc_sb[PMC_HR] = sb; 5657 5658 sb = malloc_domain(sizeof(struct pmc_samplebuffer) + 5659 pmc_nsamples * sizeof(struct pmc_sample), M_PMC, domain, 5660 M_WAITOK|M_ZERO); 5661 sb->ps_read = sb->ps_write = sb->ps_samples; 5662 sb->ps_fence = sb->ps_samples + pmc_nsamples; 5663 5664 KASSERT(pmc_pcpu[cpu] != NULL, 5665 ("[pmc,%d] cpu=%d Null per-cpu data", __LINE__, cpu)); 5666 5667 sb->ps_callchains = malloc_domain(pmc_callchaindepth * pmc_nsamples * 5668 sizeof(uintptr_t), M_PMC, domain, M_WAITOK|M_ZERO); 5669 5670 for (n = 0, ps = sb->ps_samples; n < pmc_nsamples; n++, ps++) 5671 ps->ps_pc = sb->ps_callchains + 5672 (n * pmc_callchaindepth); 5673 5674 pmc_pcpu[cpu]->pc_sb[PMC_SR] = sb; 5675 5676 sb = malloc_domain(sizeof(struct pmc_samplebuffer) + 5677 pmc_nsamples * sizeof(struct pmc_sample), M_PMC, domain, 5678 M_WAITOK|M_ZERO); 5679 sb->ps_read = sb->ps_write = sb->ps_samples; 5680 sb->ps_fence = sb->ps_samples + pmc_nsamples; 5681 5682 KASSERT(pmc_pcpu[cpu] != NULL, 5683 ("[pmc,%d] cpu=%d Null per-cpu data", __LINE__, cpu)); 5684 5685 sb->ps_callchains = malloc_domain(pmc_callchaindepth * pmc_nsamples * 5686 sizeof(uintptr_t), M_PMC, domain, M_WAITOK|M_ZERO); 5687 5688 for (n = 0, ps = sb->ps_samples; n < pmc_nsamples; n++, ps++) 5689 ps->ps_pc = sb->ps_callchains + 5690 (n * pmc_callchaindepth); 5691 5692 pmc_pcpu[cpu]->pc_sb[PMC_UR] = sb; 5693 } 5694 5695 /* allocate space for the row disposition array */ 5696 pmc_pmcdisp = malloc(sizeof(enum pmc_mode) * md->pmd_npmc, 5697 M_PMC, M_WAITOK|M_ZERO); 5698 5699 /* mark all PMCs as available */ 5700 for (n = 0; n < (int) md->pmd_npmc; n++) 5701 PMC_MARK_ROW_FREE(n); 5702 5703 /* allocate thread hash tables */ 5704 pmc_ownerhash = hashinit(pmc_hashsize, M_PMC, 5705 &pmc_ownerhashmask); 5706 5707 pmc_processhash = hashinit(pmc_hashsize, M_PMC, 5708 &pmc_processhashmask); 5709 mtx_init(&pmc_processhash_mtx, "pmc-process-hash", "pmc-leaf", 5710 MTX_SPIN); 5711 5712 CK_LIST_INIT(&pmc_ss_owners); 5713 pmc_ss_count = 0; 5714 5715 /* allocate a pool of spin mutexes */ 5716 pmc_mtxpool = mtx_pool_create("pmc-leaf", pmc_mtxpool_size, 5717 MTX_SPIN); 5718 5719 PMCDBG4(MOD,INI,1, "pmc_ownerhash=%p, mask=0x%lx " 5720 "targethash=%p mask=0x%lx", pmc_ownerhash, pmc_ownerhashmask, 5721 pmc_processhash, pmc_processhashmask); 5722 5723 /* Initialize a spin mutex for the thread free list. */ 5724 mtx_init(&pmc_threadfreelist_mtx, "pmc-threadfreelist", "pmc-leaf", 5725 MTX_SPIN); 5726 5727 /* 5728 * Initialize the callout to monitor the thread free list. 5729 * This callout will also handle the initial population of the list. 5730 */ 5731 taskqgroup_config_gtask_init(NULL, &free_gtask, pmc_thread_descriptor_pool_free_task, "thread descriptor pool free task"); 5732 5733 /* register process {exit,fork,exec} handlers */ 5734 pmc_exit_tag = EVENTHANDLER_REGISTER(process_exit, 5735 pmc_process_exit, NULL, EVENTHANDLER_PRI_ANY); 5736 pmc_fork_tag = EVENTHANDLER_REGISTER(process_fork, 5737 pmc_process_fork, NULL, EVENTHANDLER_PRI_ANY); 5738 5739 /* register kld event handlers */ 5740 pmc_kld_load_tag = EVENTHANDLER_REGISTER(kld_load, pmc_kld_load, 5741 NULL, EVENTHANDLER_PRI_ANY); 5742 pmc_kld_unload_tag = EVENTHANDLER_REGISTER(kld_unload, pmc_kld_unload, 5743 NULL, EVENTHANDLER_PRI_ANY); 5744 5745 /* initialize logging */ 5746 pmclog_initialize(); 5747 5748 /* set hook functions */ 5749 pmc_intr = md->pmd_intr; 5750 wmb(); 5751 pmc_hook = pmc_hook_handler; 5752 5753 if (error == 0) { 5754 printf(PMC_MODULE_NAME ":"); 5755 for (n = 0; n < (int) md->pmd_nclass; n++) { 5756 pcd = &md->pmd_classdep[n]; 5757 printf(" %s/%d/%d/0x%b", 5758 pmc_name_of_pmcclass(pcd->pcd_class), 5759 pcd->pcd_num, 5760 pcd->pcd_width, 5761 pcd->pcd_caps, 5762 "\20" 5763 "\1INT\2USR\3SYS\4EDG\5THR" 5764 "\6REA\7WRI\10INV\11QUA\12PRC" 5765 "\13TAG\14CSC"); 5766 } 5767 printf("\n"); 5768 } 5769 5770 return (error); 5771 } 5772 5773 /* prepare to be unloaded */ 5774 static void 5775 pmc_cleanup(void) 5776 { 5777 int c, cpu; 5778 unsigned int maxcpu; 5779 struct pmc_ownerhash *ph; 5780 struct pmc_owner *po, *tmp; 5781 struct pmc_binding pb; 5782 #ifdef HWPMC_DEBUG 5783 struct pmc_processhash *prh; 5784 #endif 5785 5786 PMCDBG0(MOD,INI,0, "cleanup"); 5787 5788 /* switch off sampling */ 5789 CPU_FOREACH(cpu) 5790 DPCPU_ID_SET(cpu, pmc_sampled, 0); 5791 pmc_intr = NULL; 5792 5793 sx_xlock(&pmc_sx); 5794 if (pmc_hook == NULL) { /* being unloaded already */ 5795 sx_xunlock(&pmc_sx); 5796 return; 5797 } 5798 5799 pmc_hook = NULL; /* prevent new threads from entering module */ 5800 5801 /* deregister event handlers */ 5802 EVENTHANDLER_DEREGISTER(process_fork, pmc_fork_tag); 5803 EVENTHANDLER_DEREGISTER(process_exit, pmc_exit_tag); 5804 EVENTHANDLER_DEREGISTER(kld_load, pmc_kld_load_tag); 5805 EVENTHANDLER_DEREGISTER(kld_unload, pmc_kld_unload_tag); 5806 5807 /* send SIGBUS to all owner threads, free up allocations */ 5808 if (pmc_ownerhash) 5809 for (ph = pmc_ownerhash; 5810 ph <= &pmc_ownerhash[pmc_ownerhashmask]; 5811 ph++) { 5812 LIST_FOREACH_SAFE(po, ph, po_next, tmp) { 5813 pmc_remove_owner(po); 5814 5815 /* send SIGBUS to owner processes */ 5816 PMCDBG3(MOD,INI,2, "cleanup signal proc=%p " 5817 "(%d, %s)", po->po_owner, 5818 po->po_owner->p_pid, 5819 po->po_owner->p_comm); 5820 5821 PROC_LOCK(po->po_owner); 5822 kern_psignal(po->po_owner, SIGBUS); 5823 PROC_UNLOCK(po->po_owner); 5824 5825 pmc_destroy_owner_descriptor(po); 5826 } 5827 } 5828 5829 /* reclaim allocated data structures */ 5830 mtx_destroy(&pmc_threadfreelist_mtx); 5831 pmc_thread_descriptor_pool_drain(); 5832 5833 if (pmc_mtxpool) 5834 mtx_pool_destroy(&pmc_mtxpool); 5835 5836 mtx_destroy(&pmc_processhash_mtx); 5837 taskqgroup_config_gtask_deinit(&free_gtask); 5838 if (pmc_processhash) { 5839 #ifdef HWPMC_DEBUG 5840 struct pmc_process *pp; 5841 5842 PMCDBG0(MOD,INI,3, "destroy process hash"); 5843 for (prh = pmc_processhash; 5844 prh <= &pmc_processhash[pmc_processhashmask]; 5845 prh++) 5846 LIST_FOREACH(pp, prh, pp_next) 5847 PMCDBG1(MOD,INI,3, "pid=%d", pp->pp_proc->p_pid); 5848 #endif 5849 5850 hashdestroy(pmc_processhash, M_PMC, pmc_processhashmask); 5851 pmc_processhash = NULL; 5852 } 5853 5854 if (pmc_ownerhash) { 5855 PMCDBG0(MOD,INI,3, "destroy owner hash"); 5856 hashdestroy(pmc_ownerhash, M_PMC, pmc_ownerhashmask); 5857 pmc_ownerhash = NULL; 5858 } 5859 5860 KASSERT(CK_LIST_EMPTY(&pmc_ss_owners), 5861 ("[pmc,%d] Global SS owner list not empty", __LINE__)); 5862 KASSERT(pmc_ss_count == 0, 5863 ("[pmc,%d] Global SS count not empty", __LINE__)); 5864 5865 /* do processor and pmc-class dependent cleanup */ 5866 maxcpu = pmc_cpu_max(); 5867 5868 PMCDBG0(MOD,INI,3, "md cleanup"); 5869 if (md) { 5870 pmc_save_cpu_binding(&pb); 5871 for (cpu = 0; cpu < maxcpu; cpu++) { 5872 PMCDBG2(MOD,INI,1,"pmc-cleanup cpu=%d pcs=%p", 5873 cpu, pmc_pcpu[cpu]); 5874 if (!pmc_cpu_is_active(cpu) || pmc_pcpu[cpu] == NULL) 5875 continue; 5876 pmc_select_cpu(cpu); 5877 for (c = 0; c < md->pmd_nclass; c++) 5878 md->pmd_classdep[c].pcd_pcpu_fini(md, cpu); 5879 if (md->pmd_pcpu_fini) 5880 md->pmd_pcpu_fini(md, cpu); 5881 } 5882 5883 if (md->pmd_cputype == PMC_CPU_GENERIC) 5884 pmc_generic_cpu_finalize(md); 5885 else 5886 pmc_md_finalize(md); 5887 5888 pmc_mdep_free(md); 5889 md = NULL; 5890 pmc_restore_cpu_binding(&pb); 5891 } 5892 5893 /* Free per-cpu descriptors. */ 5894 for (cpu = 0; cpu < maxcpu; cpu++) { 5895 if (!pmc_cpu_is_active(cpu)) 5896 continue; 5897 KASSERT(pmc_pcpu[cpu]->pc_sb[PMC_HR] != NULL, 5898 ("[pmc,%d] Null hw cpu sample buffer cpu=%d", __LINE__, 5899 cpu)); 5900 KASSERT(pmc_pcpu[cpu]->pc_sb[PMC_SR] != NULL, 5901 ("[pmc,%d] Null sw cpu sample buffer cpu=%d", __LINE__, 5902 cpu)); 5903 KASSERT(pmc_pcpu[cpu]->pc_sb[PMC_UR] != NULL, 5904 ("[pmc,%d] Null userret cpu sample buffer cpu=%d", __LINE__, 5905 cpu)); 5906 free_domain(pmc_pcpu[cpu]->pc_sb[PMC_HR]->ps_callchains, M_PMC); 5907 free_domain(pmc_pcpu[cpu]->pc_sb[PMC_HR], M_PMC); 5908 free_domain(pmc_pcpu[cpu]->pc_sb[PMC_SR]->ps_callchains, M_PMC); 5909 free_domain(pmc_pcpu[cpu]->pc_sb[PMC_SR], M_PMC); 5910 free_domain(pmc_pcpu[cpu]->pc_sb[PMC_UR]->ps_callchains, M_PMC); 5911 free_domain(pmc_pcpu[cpu]->pc_sb[PMC_UR], M_PMC); 5912 free_domain(pmc_pcpu[cpu], M_PMC); 5913 } 5914 5915 free(pmc_pcpu, M_PMC); 5916 pmc_pcpu = NULL; 5917 5918 free(pmc_pcpu_saved, M_PMC); 5919 pmc_pcpu_saved = NULL; 5920 5921 if (pmc_pmcdisp) { 5922 free(pmc_pmcdisp, M_PMC); 5923 pmc_pmcdisp = NULL; 5924 } 5925 5926 if (pmc_rowindex_to_classdep) { 5927 free(pmc_rowindex_to_classdep, M_PMC); 5928 pmc_rowindex_to_classdep = NULL; 5929 } 5930 5931 pmclog_shutdown(); 5932 counter_u64_free(pmc_stats.pm_intr_ignored); 5933 counter_u64_free(pmc_stats.pm_intr_processed); 5934 counter_u64_free(pmc_stats.pm_intr_bufferfull); 5935 counter_u64_free(pmc_stats.pm_syscalls); 5936 counter_u64_free(pmc_stats.pm_syscall_errors); 5937 counter_u64_free(pmc_stats.pm_buffer_requests); 5938 counter_u64_free(pmc_stats.pm_buffer_requests_failed); 5939 counter_u64_free(pmc_stats.pm_log_sweeps); 5940 counter_u64_free(pmc_stats.pm_merges); 5941 counter_u64_free(pmc_stats.pm_overwrites); 5942 sx_xunlock(&pmc_sx); /* we are done */ 5943 } 5944 5945 /* 5946 * The function called at load/unload. 5947 */ 5948 5949 static int 5950 load (struct module *module __unused, int cmd, void *arg __unused) 5951 { 5952 int error; 5953 5954 error = 0; 5955 5956 switch (cmd) { 5957 case MOD_LOAD : 5958 /* initialize the subsystem */ 5959 error = pmc_initialize(); 5960 if (error != 0) 5961 break; 5962 PMCDBG2(MOD,INI,1, "syscall=%d maxcpu=%d", 5963 pmc_syscall_num, pmc_cpu_max()); 5964 break; 5965 5966 5967 case MOD_UNLOAD : 5968 case MOD_SHUTDOWN: 5969 pmc_cleanup(); 5970 PMCDBG0(MOD,INI,1, "unloaded"); 5971 break; 5972 5973 default : 5974 error = EINVAL; /* XXX should panic(9) */ 5975 break; 5976 } 5977 5978 return error; 5979 } 5980