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