1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2003-2008 Joseph Koshy 5 * Copyright (c) 2007 The FreeBSD Foundation 6 * Copyright (c) 2018 Matthew Macy 7 * All rights reserved. 8 * 9 * Portions of this software were developed by A. Joseph Koshy under 10 * sponsorship from the FreeBSD Foundation and Google, Inc. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 */ 34 35 #include <sys/cdefs.h> 36 __FBSDID("$FreeBSD$"); 37 38 #include <sys/param.h> 39 #include <sys/eventhandler.h> 40 #include <sys/gtaskqueue.h> 41 #include <sys/jail.h> 42 #include <sys/kernel.h> 43 #include <sys/kthread.h> 44 #include <sys/limits.h> 45 #include <sys/lock.h> 46 #include <sys/malloc.h> 47 #include <sys/module.h> 48 #include <sys/mount.h> 49 #include <sys/mutex.h> 50 #include <sys/pmc.h> 51 #include <sys/pmckern.h> 52 #include <sys/pmclog.h> 53 #include <sys/priv.h> 54 #include <sys/proc.h> 55 #include <sys/queue.h> 56 #include <sys/resourcevar.h> 57 #include <sys/rwlock.h> 58 #include <sys/sched.h> 59 #include <sys/signalvar.h> 60 #include <sys/smp.h> 61 #include <sys/sx.h> 62 #include <sys/sysctl.h> 63 #include <sys/sysent.h> 64 #include <sys/systm.h> 65 #include <sys/vnode.h> 66 67 #include <sys/linker.h> /* needs to be after <sys/malloc.h> */ 68 69 #include <machine/atomic.h> 70 #include <machine/md_var.h> 71 72 #include <vm/vm.h> 73 #include <vm/vm_extern.h> 74 #include <vm/pmap.h> 75 #include <vm/vm_map.h> 76 #include <vm/vm_object.h> 77 78 #include "hwpmc_soft.h" 79 80 #ifdef NUMA 81 #define NDOMAINS vm_ndomains 82 #else 83 #define NDOMAINS 1 84 #define malloc_domain(size, type, domain, flags) malloc((size), (type), (flags)) 85 #define free_domain(addr, type) free(addr, type) 86 #endif 87 88 #define PMC_EPOCH_ENTER() struct epoch_tracker pmc_et; epoch_enter_preempt(global_epoch_preempt, &pmc_et) 89 #define PMC_EPOCH_EXIT() epoch_exit_preempt(global_epoch_preempt, &pmc_et) 90 91 /* 92 * Types 93 */ 94 95 enum pmc_flags { 96 PMC_FLAG_NONE = 0x00, /* do nothing */ 97 PMC_FLAG_REMOVE = 0x01, /* atomically remove entry from hash */ 98 PMC_FLAG_ALLOCATE = 0x02, /* add entry to hash if not found */ 99 PMC_FLAG_NOWAIT = 0x04, /* do not wait for mallocs */ 100 }; 101 102 /* 103 * The offset in sysent where the syscall is allocated. 104 */ 105 106 static int pmc_syscall_num = NO_SYSCALL; 107 struct pmc_cpu **pmc_pcpu; /* per-cpu state */ 108 pmc_value_t *pmc_pcpu_saved; /* saved PMC values: CSW handling */ 109 110 #define PMC_PCPU_SAVED(C,R) pmc_pcpu_saved[(R) + md->pmd_npmc*(C)] 111 112 struct mtx_pool *pmc_mtxpool; 113 static int *pmc_pmcdisp; /* PMC row dispositions */ 114 115 #define PMC_ROW_DISP_IS_FREE(R) (pmc_pmcdisp[(R)] == 0) 116 #define PMC_ROW_DISP_IS_THREAD(R) (pmc_pmcdisp[(R)] > 0) 117 #define PMC_ROW_DISP_IS_STANDALONE(R) (pmc_pmcdisp[(R)] < 0) 118 119 #define PMC_MARK_ROW_FREE(R) do { \ 120 pmc_pmcdisp[(R)] = 0; \ 121 } while (0) 122 123 #define PMC_MARK_ROW_STANDALONE(R) do { \ 124 KASSERT(pmc_pmcdisp[(R)] <= 0, ("[pmc,%d] row disposition error", \ 125 __LINE__)); \ 126 atomic_add_int(&pmc_pmcdisp[(R)], -1); \ 127 KASSERT(pmc_pmcdisp[(R)] >= (-pmc_cpu_max_active()), \ 128 ("[pmc,%d] row disposition error", __LINE__)); \ 129 } while (0) 130 131 #define PMC_UNMARK_ROW_STANDALONE(R) do { \ 132 atomic_add_int(&pmc_pmcdisp[(R)], 1); \ 133 KASSERT(pmc_pmcdisp[(R)] <= 0, ("[pmc,%d] row disposition error", \ 134 __LINE__)); \ 135 } while (0) 136 137 #define PMC_MARK_ROW_THREAD(R) do { \ 138 KASSERT(pmc_pmcdisp[(R)] >= 0, ("[pmc,%d] row disposition error", \ 139 __LINE__)); \ 140 atomic_add_int(&pmc_pmcdisp[(R)], 1); \ 141 } while (0) 142 143 #define PMC_UNMARK_ROW_THREAD(R) do { \ 144 atomic_add_int(&pmc_pmcdisp[(R)], -1); \ 145 KASSERT(pmc_pmcdisp[(R)] >= 0, ("[pmc,%d] row disposition error", \ 146 __LINE__)); \ 147 } while (0) 148 149 150 /* various event handlers */ 151 static eventhandler_tag pmc_exit_tag, pmc_fork_tag, pmc_kld_load_tag, 152 pmc_kld_unload_tag; 153 154 /* Module statistics */ 155 struct pmc_driverstats pmc_stats; 156 157 158 /* Machine/processor dependent operations */ 159 static struct pmc_mdep *md; 160 161 /* 162 * Hash tables mapping owner processes and target threads to PMCs. 163 */ 164 165 struct mtx pmc_processhash_mtx; /* spin mutex */ 166 static u_long pmc_processhashmask; 167 static LIST_HEAD(pmc_processhash, pmc_process) *pmc_processhash; 168 169 /* 170 * Hash table of PMC owner descriptors. This table is protected by 171 * the shared PMC "sx" lock. 172 */ 173 174 static u_long pmc_ownerhashmask; 175 static LIST_HEAD(pmc_ownerhash, pmc_owner) *pmc_ownerhash; 176 177 /* 178 * List of PMC owners with system-wide sampling PMCs. 179 */ 180 181 static CK_LIST_HEAD(, pmc_owner) pmc_ss_owners; 182 183 /* 184 * List of free thread entries. This is protected by the spin 185 * mutex. 186 */ 187 static struct mtx pmc_threadfreelist_mtx; /* spin mutex */ 188 static LIST_HEAD(, pmc_thread) pmc_threadfreelist; 189 static int pmc_threadfreelist_entries=0; 190 #define THREADENTRY_SIZE \ 191 (sizeof(struct pmc_thread) + (md->pmd_npmc * sizeof(struct pmc_threadpmcstate))) 192 193 /* 194 * Task to free thread descriptors 195 */ 196 static struct grouptask free_gtask; 197 198 /* 199 * A map of row indices to classdep structures. 200 */ 201 static struct pmc_classdep **pmc_rowindex_to_classdep; 202 203 /* 204 * Prototypes 205 */ 206 207 #ifdef HWPMC_DEBUG 208 static int pmc_debugflags_sysctl_handler(SYSCTL_HANDLER_ARGS); 209 static int pmc_debugflags_parse(char *newstr, char *fence); 210 #endif 211 212 static int load(struct module *module, int cmd, void *arg); 213 static int pmc_add_sample(int ring, struct pmc *pm, struct trapframe *tf); 214 static void pmc_add_thread_descriptors_from_proc(struct proc *p, 215 struct pmc_process *pp); 216 static int pmc_attach_process(struct proc *p, struct pmc *pm); 217 static struct pmc *pmc_allocate_pmc_descriptor(void); 218 static struct pmc_owner *pmc_allocate_owner_descriptor(struct proc *p); 219 static int pmc_attach_one_process(struct proc *p, struct pmc *pm); 220 static int pmc_can_allocate_rowindex(struct proc *p, unsigned int ri, 221 int cpu); 222 static int pmc_can_attach(struct pmc *pm, struct proc *p); 223 static void pmc_capture_user_callchain(int cpu, int soft, struct trapframe *tf); 224 static void pmc_cleanup(void); 225 static int pmc_detach_process(struct proc *p, struct pmc *pm); 226 static int pmc_detach_one_process(struct proc *p, struct pmc *pm, 227 int flags); 228 static void pmc_destroy_owner_descriptor(struct pmc_owner *po); 229 static void pmc_destroy_pmc_descriptor(struct pmc *pm); 230 static void pmc_destroy_process_descriptor(struct pmc_process *pp); 231 static struct pmc_owner *pmc_find_owner_descriptor(struct proc *p); 232 static int pmc_find_pmc(pmc_id_t pmcid, struct pmc **pm); 233 static struct pmc *pmc_find_pmc_descriptor_in_process(struct pmc_owner *po, 234 pmc_id_t pmc); 235 static struct pmc_process *pmc_find_process_descriptor(struct proc *p, 236 uint32_t mode); 237 static struct pmc_thread *pmc_find_thread_descriptor(struct pmc_process *pp, 238 struct thread *td, uint32_t mode); 239 static void pmc_force_context_switch(void); 240 static void pmc_link_target_process(struct pmc *pm, 241 struct pmc_process *pp); 242 static void pmc_log_all_process_mappings(struct pmc_owner *po); 243 static void pmc_log_kernel_mappings(struct pmc *pm); 244 static void pmc_log_process_mappings(struct pmc_owner *po, struct proc *p); 245 static void pmc_maybe_remove_owner(struct pmc_owner *po); 246 static void pmc_process_csw_in(struct thread *td); 247 static void pmc_process_csw_out(struct thread *td); 248 static void pmc_process_exit(void *arg, struct proc *p); 249 static void pmc_process_fork(void *arg, struct proc *p1, 250 struct proc *p2, int n); 251 static void pmc_process_samples(int cpu, int soft); 252 static void pmc_release_pmc_descriptor(struct pmc *pmc); 253 static void pmc_process_thread_add(struct thread *td); 254 static void pmc_process_thread_delete(struct thread *td); 255 static void pmc_process_thread_userret(struct thread *td); 256 static void pmc_remove_owner(struct pmc_owner *po); 257 static void pmc_remove_process_descriptor(struct pmc_process *pp); 258 static void pmc_restore_cpu_binding(struct pmc_binding *pb); 259 static void pmc_save_cpu_binding(struct pmc_binding *pb); 260 static void pmc_select_cpu(int cpu); 261 static int pmc_start(struct pmc *pm); 262 static int pmc_stop(struct pmc *pm); 263 static int pmc_syscall_handler(struct thread *td, void *syscall_args); 264 static struct pmc_thread *pmc_thread_descriptor_pool_alloc(void); 265 static void pmc_thread_descriptor_pool_drain(void); 266 static void pmc_thread_descriptor_pool_free(struct pmc_thread *pt); 267 static void pmc_unlink_target_process(struct pmc *pmc, 268 struct pmc_process *pp); 269 static int generic_switch_in(struct pmc_cpu *pc, struct pmc_process *pp); 270 static int generic_switch_out(struct pmc_cpu *pc, struct pmc_process *pp); 271 static struct pmc_mdep *pmc_generic_cpu_initialize(void); 272 static void pmc_generic_cpu_finalize(struct pmc_mdep *md); 273 static void pmc_post_callchain_callback(void); 274 static void pmc_process_threadcreate(struct thread *td); 275 static void pmc_process_threadexit(struct thread *td); 276 static void pmc_process_proccreate(struct proc *p); 277 static void pmc_process_allproc(struct pmc *pm); 278 279 /* 280 * Kernel tunables and sysctl(8) interface. 281 */ 282 283 SYSCTL_DECL(_kern_hwpmc); 284 SYSCTL_NODE(_kern_hwpmc, OID_AUTO, stats, CTLFLAG_RW, 0, "HWPMC stats"); 285 286 287 /* Stats. */ 288 SYSCTL_COUNTER_U64(_kern_hwpmc_stats, OID_AUTO, intr_ignored, CTLFLAG_RW, 289 &pmc_stats.pm_intr_ignored, "# of interrupts ignored"); 290 SYSCTL_COUNTER_U64(_kern_hwpmc_stats, OID_AUTO, intr_processed, CTLFLAG_RW, 291 &pmc_stats.pm_intr_processed, "# of interrupts processed"); 292 SYSCTL_COUNTER_U64(_kern_hwpmc_stats, OID_AUTO, intr_bufferfull, CTLFLAG_RW, 293 &pmc_stats.pm_intr_bufferfull, "# of interrupts where buffer was full"); 294 SYSCTL_COUNTER_U64(_kern_hwpmc_stats, OID_AUTO, syscalls, CTLFLAG_RW, 295 &pmc_stats.pm_syscalls, "# of syscalls"); 296 SYSCTL_COUNTER_U64(_kern_hwpmc_stats, OID_AUTO, syscall_errors, CTLFLAG_RW, 297 &pmc_stats.pm_syscall_errors, "# of syscall_errors"); 298 SYSCTL_COUNTER_U64(_kern_hwpmc_stats, OID_AUTO, buffer_requests, CTLFLAG_RW, 299 &pmc_stats.pm_buffer_requests, "# of buffer requests"); 300 SYSCTL_COUNTER_U64(_kern_hwpmc_stats, OID_AUTO, buffer_requests_failed, CTLFLAG_RW, 301 &pmc_stats.pm_buffer_requests_failed, "# of buffer requests which failed"); 302 SYSCTL_COUNTER_U64(_kern_hwpmc_stats, OID_AUTO, log_sweeps, CTLFLAG_RW, 303 &pmc_stats.pm_log_sweeps, "# of ?"); 304 SYSCTL_COUNTER_U64(_kern_hwpmc_stats, OID_AUTO, merges, CTLFLAG_RW, 305 &pmc_stats.pm_merges, "# of times kernel stack was found for user trace"); 306 SYSCTL_COUNTER_U64(_kern_hwpmc_stats, OID_AUTO, overwrites, CTLFLAG_RW, 307 &pmc_stats.pm_overwrites, "# of times a sample was overwritten before being logged"); 308 309 static int pmc_callchaindepth = PMC_CALLCHAIN_DEPTH; 310 SYSCTL_INT(_kern_hwpmc, OID_AUTO, callchaindepth, CTLFLAG_RDTUN, 311 &pmc_callchaindepth, 0, "depth of call chain records"); 312 313 char pmc_cpuid[64]; 314 SYSCTL_STRING(_kern_hwpmc, OID_AUTO, cpuid, CTLFLAG_RD, 315 pmc_cpuid, 0, "cpu version string"); 316 #ifdef HWPMC_DEBUG 317 struct pmc_debugflags pmc_debugflags = PMC_DEBUG_DEFAULT_FLAGS; 318 char pmc_debugstr[PMC_DEBUG_STRSIZE]; 319 TUNABLE_STR(PMC_SYSCTL_NAME_PREFIX "debugflags", pmc_debugstr, 320 sizeof(pmc_debugstr)); 321 SYSCTL_PROC(_kern_hwpmc, OID_AUTO, debugflags, 322 CTLTYPE_STRING | CTLFLAG_RWTUN | CTLFLAG_NOFETCH, 323 0, 0, pmc_debugflags_sysctl_handler, "A", "debug flags"); 324 #endif 325 326 327 /* 328 * kern.hwpmc.hashrows -- determines the number of rows in the 329 * of the hash table used to look up threads 330 */ 331 332 static int pmc_hashsize = PMC_HASH_SIZE; 333 SYSCTL_INT(_kern_hwpmc, OID_AUTO, hashsize, CTLFLAG_RDTUN, 334 &pmc_hashsize, 0, "rows in hash tables"); 335 336 /* 337 * kern.hwpmc.nsamples --- number of PC samples/callchain stacks per CPU 338 */ 339 340 static int pmc_nsamples = PMC_NSAMPLES; 341 SYSCTL_INT(_kern_hwpmc, OID_AUTO, nsamples, CTLFLAG_RDTUN, 342 &pmc_nsamples, 0, "number of PC samples per CPU"); 343 344 345 /* 346 * kern.hwpmc.mtxpoolsize -- number of mutexes in the mutex pool. 347 */ 348 349 static int pmc_mtxpool_size = PMC_MTXPOOL_SIZE; 350 SYSCTL_INT(_kern_hwpmc, OID_AUTO, mtxpoolsize, CTLFLAG_RDTUN, 351 &pmc_mtxpool_size, 0, "size of spin mutex pool"); 352 353 354 /* 355 * kern.hwpmc.threadfreelist_entries -- number of free entries 356 */ 357 358 SYSCTL_INT(_kern_hwpmc, OID_AUTO, threadfreelist_entries, CTLFLAG_RD, 359 &pmc_threadfreelist_entries, 0, "number of avalable thread entries"); 360 361 362 /* 363 * kern.hwpmc.threadfreelist_max -- maximum number of free entries 364 */ 365 366 static int pmc_threadfreelist_max = PMC_THREADLIST_MAX; 367 SYSCTL_INT(_kern_hwpmc, OID_AUTO, threadfreelist_max, CTLFLAG_RW, 368 &pmc_threadfreelist_max, 0, 369 "maximum number of available thread entries before freeing some"); 370 371 372 /* 373 * security.bsd.unprivileged_syspmcs -- allow non-root processes to 374 * allocate system-wide PMCs. 375 * 376 * Allowing unprivileged processes to allocate system PMCs is convenient 377 * if system-wide measurements need to be taken concurrently with other 378 * per-process measurements. This feature is turned off by default. 379 */ 380 381 static int pmc_unprivileged_syspmcs = 0; 382 SYSCTL_INT(_security_bsd, OID_AUTO, unprivileged_syspmcs, CTLFLAG_RWTUN, 383 &pmc_unprivileged_syspmcs, 0, 384 "allow unprivileged process to allocate system PMCs"); 385 386 /* 387 * Hash function. Discard the lower 2 bits of the pointer since 388 * these are always zero for our uses. The hash multiplier is 389 * round((2^LONG_BIT) * ((sqrt(5)-1)/2)). 390 */ 391 392 #if LONG_BIT == 64 393 #define _PMC_HM 11400714819323198486u 394 #elif LONG_BIT == 32 395 #define _PMC_HM 2654435769u 396 #else 397 #error Must know the size of 'long' to compile 398 #endif 399 400 #define PMC_HASH_PTR(P,M) ((((unsigned long) (P) >> 2) * _PMC_HM) & (M)) 401 402 /* 403 * Syscall structures 404 */ 405 406 /* The `sysent' for the new syscall */ 407 static struct sysent pmc_sysent = { 408 .sy_narg = 2, 409 .sy_call = pmc_syscall_handler, 410 }; 411 412 static struct syscall_module_data pmc_syscall_mod = { 413 .chainevh = load, 414 .chainarg = NULL, 415 .offset = &pmc_syscall_num, 416 .new_sysent = &pmc_sysent, 417 .old_sysent = { .sy_narg = 0, .sy_call = NULL }, 418 .flags = SY_THR_STATIC_KLD, 419 }; 420 421 static moduledata_t pmc_mod = { 422 .name = PMC_MODULE_NAME, 423 .evhand = syscall_module_handler, 424 .priv = &pmc_syscall_mod, 425 }; 426 427 #ifdef EARLY_AP_STARTUP 428 DECLARE_MODULE(pmc, pmc_mod, SI_SUB_SYSCALLS, SI_ORDER_ANY); 429 #else 430 DECLARE_MODULE(pmc, pmc_mod, SI_SUB_SMP, SI_ORDER_ANY); 431 #endif 432 MODULE_VERSION(pmc, PMC_VERSION); 433 434 #ifdef HWPMC_DEBUG 435 enum pmc_dbgparse_state { 436 PMCDS_WS, /* in whitespace */ 437 PMCDS_MAJOR, /* seen a major keyword */ 438 PMCDS_MINOR 439 }; 440 441 static int 442 pmc_debugflags_parse(char *newstr, char *fence) 443 { 444 char c, *p, *q; 445 struct pmc_debugflags *tmpflags; 446 int error, found, *newbits, tmp; 447 size_t kwlen; 448 449 tmpflags = malloc(sizeof(*tmpflags), M_PMC, M_WAITOK|M_ZERO); 450 451 p = newstr; 452 error = 0; 453 454 for (; p < fence && (c = *p); p++) { 455 456 /* skip white space */ 457 if (c == ' ' || c == '\t') 458 continue; 459 460 /* look for a keyword followed by "=" */ 461 for (q = p; p < fence && (c = *p) && c != '='; p++) 462 ; 463 if (c != '=') { 464 error = EINVAL; 465 goto done; 466 } 467 468 kwlen = p - q; 469 newbits = NULL; 470 471 /* lookup flag group name */ 472 #define DBG_SET_FLAG_MAJ(S,F) \ 473 if (kwlen == sizeof(S)-1 && strncmp(q, S, kwlen) == 0) \ 474 newbits = &tmpflags->pdb_ ## F; 475 476 DBG_SET_FLAG_MAJ("cpu", CPU); 477 DBG_SET_FLAG_MAJ("csw", CSW); 478 DBG_SET_FLAG_MAJ("logging", LOG); 479 DBG_SET_FLAG_MAJ("module", MOD); 480 DBG_SET_FLAG_MAJ("md", MDP); 481 DBG_SET_FLAG_MAJ("owner", OWN); 482 DBG_SET_FLAG_MAJ("pmc", PMC); 483 DBG_SET_FLAG_MAJ("process", PRC); 484 DBG_SET_FLAG_MAJ("sampling", SAM); 485 486 if (newbits == NULL) { 487 error = EINVAL; 488 goto done; 489 } 490 491 p++; /* skip the '=' */ 492 493 /* Now parse the individual flags */ 494 tmp = 0; 495 newflag: 496 for (q = p; p < fence && (c = *p); p++) 497 if (c == ' ' || c == '\t' || c == ',') 498 break; 499 500 /* p == fence or c == ws or c == "," or c == 0 */ 501 502 if ((kwlen = p - q) == 0) { 503 *newbits = tmp; 504 continue; 505 } 506 507 found = 0; 508 #define DBG_SET_FLAG_MIN(S,F) \ 509 if (kwlen == sizeof(S)-1 && strncmp(q, S, kwlen) == 0) \ 510 tmp |= found = (1 << PMC_DEBUG_MIN_ ## F) 511 512 /* a '*' denotes all possible flags in the group */ 513 if (kwlen == 1 && *q == '*') 514 tmp = found = ~0; 515 /* look for individual flag names */ 516 DBG_SET_FLAG_MIN("allocaterow", ALR); 517 DBG_SET_FLAG_MIN("allocate", ALL); 518 DBG_SET_FLAG_MIN("attach", ATT); 519 DBG_SET_FLAG_MIN("bind", BND); 520 DBG_SET_FLAG_MIN("config", CFG); 521 DBG_SET_FLAG_MIN("exec", EXC); 522 DBG_SET_FLAG_MIN("exit", EXT); 523 DBG_SET_FLAG_MIN("find", FND); 524 DBG_SET_FLAG_MIN("flush", FLS); 525 DBG_SET_FLAG_MIN("fork", FRK); 526 DBG_SET_FLAG_MIN("getbuf", GTB); 527 DBG_SET_FLAG_MIN("hook", PMH); 528 DBG_SET_FLAG_MIN("init", INI); 529 DBG_SET_FLAG_MIN("intr", INT); 530 DBG_SET_FLAG_MIN("linktarget", TLK); 531 DBG_SET_FLAG_MIN("mayberemove", OMR); 532 DBG_SET_FLAG_MIN("ops", OPS); 533 DBG_SET_FLAG_MIN("read", REA); 534 DBG_SET_FLAG_MIN("register", REG); 535 DBG_SET_FLAG_MIN("release", REL); 536 DBG_SET_FLAG_MIN("remove", ORM); 537 DBG_SET_FLAG_MIN("sample", SAM); 538 DBG_SET_FLAG_MIN("scheduleio", SIO); 539 DBG_SET_FLAG_MIN("select", SEL); 540 DBG_SET_FLAG_MIN("signal", SIG); 541 DBG_SET_FLAG_MIN("swi", SWI); 542 DBG_SET_FLAG_MIN("swo", SWO); 543 DBG_SET_FLAG_MIN("start", STA); 544 DBG_SET_FLAG_MIN("stop", STO); 545 DBG_SET_FLAG_MIN("syscall", PMS); 546 DBG_SET_FLAG_MIN("unlinktarget", TUL); 547 DBG_SET_FLAG_MIN("write", WRI); 548 if (found == 0) { 549 /* unrecognized flag name */ 550 error = EINVAL; 551 goto done; 552 } 553 554 if (c == 0 || c == ' ' || c == '\t') { /* end of flag group */ 555 *newbits = tmp; 556 continue; 557 } 558 559 p++; 560 goto newflag; 561 } 562 563 /* save the new flag set */ 564 bcopy(tmpflags, &pmc_debugflags, sizeof(pmc_debugflags)); 565 566 done: 567 free(tmpflags, M_PMC); 568 return error; 569 } 570 571 static int 572 pmc_debugflags_sysctl_handler(SYSCTL_HANDLER_ARGS) 573 { 574 char *fence, *newstr; 575 int error; 576 unsigned int n; 577 578 (void) arg1; (void) arg2; /* unused parameters */ 579 580 n = sizeof(pmc_debugstr); 581 newstr = malloc(n, M_PMC, M_WAITOK|M_ZERO); 582 (void) strlcpy(newstr, pmc_debugstr, n); 583 584 error = sysctl_handle_string(oidp, newstr, n, req); 585 586 /* if there is a new string, parse and copy it */ 587 if (error == 0 && req->newptr != NULL) { 588 fence = newstr + (n < req->newlen ? n : req->newlen + 1); 589 if ((error = pmc_debugflags_parse(newstr, fence)) == 0) 590 (void) strlcpy(pmc_debugstr, newstr, 591 sizeof(pmc_debugstr)); 592 } 593 594 free(newstr, M_PMC); 595 596 return error; 597 } 598 #endif 599 600 /* 601 * Map a row index to a classdep structure and return the adjusted row 602 * index for the PMC class index. 603 */ 604 static struct pmc_classdep * 605 pmc_ri_to_classdep(struct pmc_mdep *md, int ri, int *adjri) 606 { 607 struct pmc_classdep *pcd; 608 609 (void) md; 610 611 KASSERT(ri >= 0 && ri < md->pmd_npmc, 612 ("[pmc,%d] illegal row-index %d", __LINE__, ri)); 613 614 pcd = pmc_rowindex_to_classdep[ri]; 615 616 KASSERT(pcd != NULL, 617 ("[pmc,%d] ri %d null pcd", __LINE__, ri)); 618 619 *adjri = ri - pcd->pcd_ri; 620 621 KASSERT(*adjri >= 0 && *adjri < pcd->pcd_num, 622 ("[pmc,%d] adjusted row-index %d", __LINE__, *adjri)); 623 624 return (pcd); 625 } 626 627 /* 628 * Concurrency Control 629 * 630 * The driver manages the following data structures: 631 * 632 * - target process descriptors, one per target process 633 * - owner process descriptors (and attached lists), one per owner process 634 * - lookup hash tables for owner and target processes 635 * - PMC descriptors (and attached lists) 636 * - per-cpu hardware state 637 * - the 'hook' variable through which the kernel calls into 638 * this module 639 * - the machine hardware state (managed by the MD layer) 640 * 641 * These data structures are accessed from: 642 * 643 * - thread context-switch code 644 * - interrupt handlers (possibly on multiple cpus) 645 * - kernel threads on multiple cpus running on behalf of user 646 * processes doing system calls 647 * - this driver's private kernel threads 648 * 649 * = Locks and Locking strategy = 650 * 651 * The driver uses four locking strategies for its operation: 652 * 653 * - The global SX lock "pmc_sx" is used to protect internal 654 * data structures. 655 * 656 * Calls into the module by syscall() start with this lock being 657 * held in exclusive mode. Depending on the requested operation, 658 * the lock may be downgraded to 'shared' mode to allow more 659 * concurrent readers into the module. Calls into the module from 660 * other parts of the kernel acquire the lock in shared mode. 661 * 662 * This SX lock is held in exclusive mode for any operations that 663 * modify the linkages between the driver's internal data structures. 664 * 665 * The 'pmc_hook' function pointer is also protected by this lock. 666 * It is only examined with the sx lock held in exclusive mode. The 667 * kernel module is allowed to be unloaded only with the sx lock held 668 * in exclusive mode. In normal syscall handling, after acquiring the 669 * pmc_sx lock we first check that 'pmc_hook' is non-null before 670 * proceeding. This prevents races between the thread unloading the module 671 * and other threads seeking to use the module. 672 * 673 * - Lookups of target process structures and owner process structures 674 * cannot use the global "pmc_sx" SX lock because these lookups need 675 * to happen during context switches and in other critical sections 676 * where sleeping is not allowed. We protect these lookup tables 677 * with their own private spin-mutexes, "pmc_processhash_mtx" and 678 * "pmc_ownerhash_mtx". 679 * 680 * - Interrupt handlers work in a lock free manner. At interrupt 681 * time, handlers look at the PMC pointer (phw->phw_pmc) configured 682 * when the PMC was started. If this pointer is NULL, the interrupt 683 * is ignored after updating driver statistics. We ensure that this 684 * pointer is set (using an atomic operation if necessary) before the 685 * PMC hardware is started. Conversely, this pointer is unset atomically 686 * only after the PMC hardware is stopped. 687 * 688 * We ensure that everything needed for the operation of an 689 * interrupt handler is available without it needing to acquire any 690 * locks. We also ensure that a PMC's software state is destroyed only 691 * after the PMC is taken off hardware (on all CPUs). 692 * 693 * - Context-switch handling with process-private PMCs needs more 694 * care. 695 * 696 * A given process may be the target of multiple PMCs. For example, 697 * PMCATTACH and PMCDETACH may be requested by a process on one CPU 698 * while the target process is running on another. A PMC could also 699 * be getting released because its owner is exiting. We tackle 700 * these situations in the following manner: 701 * 702 * - each target process structure 'pmc_process' has an array 703 * of 'struct pmc *' pointers, one for each hardware PMC. 704 * 705 * - At context switch IN time, each "target" PMC in RUNNING state 706 * gets started on hardware and a pointer to each PMC is copied into 707 * the per-cpu phw array. The 'runcount' for the PMC is 708 * incremented. 709 * 710 * - At context switch OUT time, all process-virtual PMCs are stopped 711 * on hardware. The saved value is added to the PMCs value field 712 * only if the PMC is in a non-deleted state (the PMCs state could 713 * have changed during the current time slice). 714 * 715 * Note that since in-between a switch IN on a processor and a switch 716 * OUT, the PMC could have been released on another CPU. Therefore 717 * context switch OUT always looks at the hardware state to turn 718 * OFF PMCs and will update a PMC's saved value only if reachable 719 * from the target process record. 720 * 721 * - OP PMCRELEASE could be called on a PMC at any time (the PMC could 722 * be attached to many processes at the time of the call and could 723 * be active on multiple CPUs). 724 * 725 * We prevent further scheduling of the PMC by marking it as in 726 * state 'DELETED'. If the runcount of the PMC is non-zero then 727 * this PMC is currently running on a CPU somewhere. The thread 728 * doing the PMCRELEASE operation waits by repeatedly doing a 729 * pause() till the runcount comes to zero. 730 * 731 * The contents of a PMC descriptor (struct pmc) are protected using 732 * a spin-mutex. In order to save space, we use a mutex pool. 733 * 734 * In terms of lock types used by witness(4), we use: 735 * - Type "pmc-sx", used by the global SX lock. 736 * - Type "pmc-sleep", for sleep mutexes used by logger threads. 737 * - Type "pmc-per-proc", for protecting PMC owner descriptors. 738 * - Type "pmc-leaf", used for all other spin mutexes. 739 */ 740 741 /* 742 * save the cpu binding of the current kthread 743 */ 744 745 static void 746 pmc_save_cpu_binding(struct pmc_binding *pb) 747 { 748 PMCDBG0(CPU,BND,2, "save-cpu"); 749 thread_lock(curthread); 750 pb->pb_bound = sched_is_bound(curthread); 751 pb->pb_cpu = curthread->td_oncpu; 752 thread_unlock(curthread); 753 PMCDBG1(CPU,BND,2, "save-cpu cpu=%d", pb->pb_cpu); 754 } 755 756 /* 757 * restore the cpu binding of the current thread 758 */ 759 760 static void 761 pmc_restore_cpu_binding(struct pmc_binding *pb) 762 { 763 PMCDBG2(CPU,BND,2, "restore-cpu curcpu=%d restore=%d", 764 curthread->td_oncpu, pb->pb_cpu); 765 thread_lock(curthread); 766 if (pb->pb_bound) 767 sched_bind(curthread, pb->pb_cpu); 768 else 769 sched_unbind(curthread); 770 thread_unlock(curthread); 771 PMCDBG0(CPU,BND,2, "restore-cpu done"); 772 } 773 774 /* 775 * move execution over the specified cpu and bind it there. 776 */ 777 778 static void 779 pmc_select_cpu(int cpu) 780 { 781 KASSERT(cpu >= 0 && cpu < pmc_cpu_max(), 782 ("[pmc,%d] bad cpu number %d", __LINE__, cpu)); 783 784 /* Never move to an inactive CPU. */ 785 KASSERT(pmc_cpu_is_active(cpu), ("[pmc,%d] selecting inactive " 786 "CPU %d", __LINE__, cpu)); 787 788 PMCDBG1(CPU,SEL,2, "select-cpu cpu=%d", cpu); 789 thread_lock(curthread); 790 sched_bind(curthread, cpu); 791 thread_unlock(curthread); 792 793 KASSERT(curthread->td_oncpu == cpu, 794 ("[pmc,%d] CPU not bound [cpu=%d, curr=%d]", __LINE__, 795 cpu, curthread->td_oncpu)); 796 797 PMCDBG1(CPU,SEL,2, "select-cpu cpu=%d ok", cpu); 798 } 799 800 /* 801 * Force a context switch. 802 * 803 * We do this by pause'ing for 1 tick -- invoking mi_switch() is not 804 * guaranteed to force a context switch. 805 */ 806 807 static void 808 pmc_force_context_switch(void) 809 { 810 811 pause("pmcctx", 1); 812 } 813 814 uint64_t 815 pmc_rdtsc(void) 816 { 817 #if defined(__i386__) || defined(__amd64__) 818 if (__predict_true(amd_feature & AMDID_RDTSCP)) 819 return rdtscp(); 820 else 821 return rdtsc(); 822 #else 823 return get_cyclecount(); 824 #endif 825 } 826 827 /* 828 * Get the file name for an executable. This is a simple wrapper 829 * around vn_fullpath(9). 830 */ 831 832 static void 833 pmc_getfilename(struct vnode *v, char **fullpath, char **freepath) 834 { 835 836 *fullpath = "unknown"; 837 *freepath = NULL; 838 vn_fullpath(curthread, v, fullpath, freepath); 839 } 840 841 /* 842 * remove an process owning PMCs 843 */ 844 845 void 846 pmc_remove_owner(struct pmc_owner *po) 847 { 848 struct pmc *pm, *tmp; 849 850 sx_assert(&pmc_sx, SX_XLOCKED); 851 852 PMCDBG1(OWN,ORM,1, "remove-owner po=%p", po); 853 854 /* Remove descriptor from the owner hash table */ 855 LIST_REMOVE(po, po_next); 856 857 /* release all owned PMC descriptors */ 858 LIST_FOREACH_SAFE(pm, &po->po_pmcs, pm_next, tmp) { 859 PMCDBG1(OWN,ORM,2, "pmc=%p", pm); 860 KASSERT(pm->pm_owner == po, 861 ("[pmc,%d] owner %p != po %p", __LINE__, pm->pm_owner, po)); 862 863 pmc_release_pmc_descriptor(pm); /* will unlink from the list */ 864 pmc_destroy_pmc_descriptor(pm); 865 } 866 867 KASSERT(po->po_sscount == 0, 868 ("[pmc,%d] SS count not zero", __LINE__)); 869 KASSERT(LIST_EMPTY(&po->po_pmcs), 870 ("[pmc,%d] PMC list not empty", __LINE__)); 871 872 /* de-configure the log file if present */ 873 if (po->po_flags & PMC_PO_OWNS_LOGFILE) 874 pmclog_deconfigure_log(po); 875 } 876 877 /* 878 * remove an owner process record if all conditions are met. 879 */ 880 881 static void 882 pmc_maybe_remove_owner(struct pmc_owner *po) 883 { 884 885 PMCDBG1(OWN,OMR,1, "maybe-remove-owner po=%p", po); 886 887 /* 888 * Remove owner record if 889 * - this process does not own any PMCs 890 * - this process has not allocated a system-wide sampling buffer 891 */ 892 893 if (LIST_EMPTY(&po->po_pmcs) && 894 ((po->po_flags & PMC_PO_OWNS_LOGFILE) == 0)) { 895 pmc_remove_owner(po); 896 pmc_destroy_owner_descriptor(po); 897 } 898 } 899 900 /* 901 * Add an association between a target process and a PMC. 902 */ 903 904 static void 905 pmc_link_target_process(struct pmc *pm, struct pmc_process *pp) 906 { 907 int ri; 908 struct pmc_target *pt; 909 #ifdef INVARIANTS 910 struct pmc_thread *pt_td; 911 #endif 912 913 sx_assert(&pmc_sx, SX_XLOCKED); 914 915 KASSERT(pm != NULL && pp != NULL, 916 ("[pmc,%d] Null pm %p or pp %p", __LINE__, pm, pp)); 917 KASSERT(PMC_IS_VIRTUAL_MODE(PMC_TO_MODE(pm)), 918 ("[pmc,%d] Attaching a non-process-virtual pmc=%p to pid=%d", 919 __LINE__, pm, pp->pp_proc->p_pid)); 920 KASSERT(pp->pp_refcnt >= 0 && pp->pp_refcnt <= ((int) md->pmd_npmc - 1), 921 ("[pmc,%d] Illegal reference count %d for process record %p", 922 __LINE__, pp->pp_refcnt, (void *) pp)); 923 924 ri = PMC_TO_ROWINDEX(pm); 925 926 PMCDBG3(PRC,TLK,1, "link-target pmc=%p ri=%d pmc-process=%p", 927 pm, ri, pp); 928 929 #ifdef HWPMC_DEBUG 930 LIST_FOREACH(pt, &pm->pm_targets, pt_next) 931 if (pt->pt_process == pp) 932 KASSERT(0, ("[pmc,%d] pp %p already in pmc %p targets", 933 __LINE__, pp, pm)); 934 #endif 935 936 pt = malloc(sizeof(struct pmc_target), M_PMC, M_WAITOK|M_ZERO); 937 pt->pt_process = pp; 938 939 LIST_INSERT_HEAD(&pm->pm_targets, pt, pt_next); 940 941 atomic_store_rel_ptr((uintptr_t *)&pp->pp_pmcs[ri].pp_pmc, 942 (uintptr_t)pm); 943 944 if (pm->pm_owner->po_owner == pp->pp_proc) 945 pm->pm_flags |= PMC_F_ATTACHED_TO_OWNER; 946 947 /* 948 * Initialize the per-process values at this row index. 949 */ 950 pp->pp_pmcs[ri].pp_pmcval = PMC_TO_MODE(pm) == PMC_MODE_TS ? 951 pm->pm_sc.pm_reloadcount : 0; 952 953 pp->pp_refcnt++; 954 955 #ifdef INVARIANTS 956 /* Confirm that the per-thread values at this row index are cleared. */ 957 if (PMC_TO_MODE(pm) == PMC_MODE_TS) { 958 mtx_lock_spin(pp->pp_tdslock); 959 LIST_FOREACH(pt_td, &pp->pp_tds, pt_next) { 960 KASSERT(pt_td->pt_pmcs[ri].pt_pmcval == (pmc_value_t) 0, 961 ("[pmc,%d] pt_pmcval not cleared for pid=%d at " 962 "ri=%d", __LINE__, pp->pp_proc->p_pid, ri)); 963 } 964 mtx_unlock_spin(pp->pp_tdslock); 965 } 966 #endif 967 } 968 969 /* 970 * Removes the association between a target process and a PMC. 971 */ 972 973 static void 974 pmc_unlink_target_process(struct pmc *pm, struct pmc_process *pp) 975 { 976 int ri; 977 struct proc *p; 978 struct pmc_target *ptgt; 979 struct pmc_thread *pt; 980 981 sx_assert(&pmc_sx, SX_XLOCKED); 982 983 KASSERT(pm != NULL && pp != NULL, 984 ("[pmc,%d] Null pm %p or pp %p", __LINE__, pm, pp)); 985 986 KASSERT(pp->pp_refcnt >= 1 && pp->pp_refcnt <= (int) md->pmd_npmc, 987 ("[pmc,%d] Illegal ref count %d on process record %p", 988 __LINE__, pp->pp_refcnt, (void *) pp)); 989 990 ri = PMC_TO_ROWINDEX(pm); 991 992 PMCDBG3(PRC,TUL,1, "unlink-target pmc=%p ri=%d pmc-process=%p", 993 pm, ri, pp); 994 995 KASSERT(pp->pp_pmcs[ri].pp_pmc == pm, 996 ("[pmc,%d] PMC ri %d mismatch pmc %p pp->[ri] %p", __LINE__, 997 ri, pm, pp->pp_pmcs[ri].pp_pmc)); 998 999 pp->pp_pmcs[ri].pp_pmc = NULL; 1000 pp->pp_pmcs[ri].pp_pmcval = (pmc_value_t) 0; 1001 1002 /* Clear the per-thread values at this row index. */ 1003 if (PMC_TO_MODE(pm) == PMC_MODE_TS) { 1004 mtx_lock_spin(pp->pp_tdslock); 1005 LIST_FOREACH(pt, &pp->pp_tds, pt_next) 1006 pt->pt_pmcs[ri].pt_pmcval = (pmc_value_t) 0; 1007 mtx_unlock_spin(pp->pp_tdslock); 1008 } 1009 1010 /* Remove owner-specific flags */ 1011 if (pm->pm_owner->po_owner == pp->pp_proc) { 1012 pp->pp_flags &= ~PMC_PP_ENABLE_MSR_ACCESS; 1013 pm->pm_flags &= ~PMC_F_ATTACHED_TO_OWNER; 1014 } 1015 1016 pp->pp_refcnt--; 1017 1018 /* Remove the target process from the PMC structure */ 1019 LIST_FOREACH(ptgt, &pm->pm_targets, pt_next) 1020 if (ptgt->pt_process == pp) 1021 break; 1022 1023 KASSERT(ptgt != NULL, ("[pmc,%d] process %p (pp: %p) not found " 1024 "in pmc %p", __LINE__, pp->pp_proc, pp, pm)); 1025 1026 LIST_REMOVE(ptgt, pt_next); 1027 free(ptgt, M_PMC); 1028 1029 /* if the PMC now lacks targets, send the owner a SIGIO */ 1030 if (LIST_EMPTY(&pm->pm_targets)) { 1031 p = pm->pm_owner->po_owner; 1032 PROC_LOCK(p); 1033 kern_psignal(p, SIGIO); 1034 PROC_UNLOCK(p); 1035 1036 PMCDBG2(PRC,SIG,2, "signalling proc=%p signal=%d", p, 1037 SIGIO); 1038 } 1039 } 1040 1041 /* 1042 * Check if PMC 'pm' may be attached to target process 't'. 1043 */ 1044 1045 static int 1046 pmc_can_attach(struct pmc *pm, struct proc *t) 1047 { 1048 struct proc *o; /* pmc owner */ 1049 struct ucred *oc, *tc; /* owner, target credentials */ 1050 int decline_attach, i; 1051 1052 /* 1053 * A PMC's owner can always attach that PMC to itself. 1054 */ 1055 1056 if ((o = pm->pm_owner->po_owner) == t) 1057 return 0; 1058 1059 PROC_LOCK(o); 1060 oc = o->p_ucred; 1061 crhold(oc); 1062 PROC_UNLOCK(o); 1063 1064 PROC_LOCK(t); 1065 tc = t->p_ucred; 1066 crhold(tc); 1067 PROC_UNLOCK(t); 1068 1069 /* 1070 * The effective uid of the PMC owner should match at least one 1071 * of the {effective,real,saved} uids of the target process. 1072 */ 1073 1074 decline_attach = oc->cr_uid != tc->cr_uid && 1075 oc->cr_uid != tc->cr_svuid && 1076 oc->cr_uid != tc->cr_ruid; 1077 1078 /* 1079 * Every one of the target's group ids, must be in the owner's 1080 * group list. 1081 */ 1082 for (i = 0; !decline_attach && i < tc->cr_ngroups; i++) 1083 decline_attach = !groupmember(tc->cr_groups[i], oc); 1084 1085 /* check the read and saved gids too */ 1086 if (decline_attach == 0) 1087 decline_attach = !groupmember(tc->cr_rgid, oc) || 1088 !groupmember(tc->cr_svgid, oc); 1089 1090 crfree(tc); 1091 crfree(oc); 1092 1093 return !decline_attach; 1094 } 1095 1096 /* 1097 * Attach a process to a PMC. 1098 */ 1099 1100 static int 1101 pmc_attach_one_process(struct proc *p, struct pmc *pm) 1102 { 1103 int ri, error; 1104 char *fullpath, *freepath; 1105 struct pmc_process *pp; 1106 1107 sx_assert(&pmc_sx, SX_XLOCKED); 1108 1109 PMCDBG5(PRC,ATT,2, "attach-one pm=%p ri=%d proc=%p (%d, %s)", pm, 1110 PMC_TO_ROWINDEX(pm), p, p->p_pid, p->p_comm); 1111 1112 /* 1113 * Locate the process descriptor corresponding to process 'p', 1114 * allocating space as needed. 1115 * 1116 * Verify that rowindex 'pm_rowindex' is free in the process 1117 * descriptor. 1118 * 1119 * If not, allocate space for a descriptor and link the 1120 * process descriptor and PMC. 1121 */ 1122 ri = PMC_TO_ROWINDEX(pm); 1123 1124 /* mark process as using HWPMCs */ 1125 PROC_LOCK(p); 1126 p->p_flag |= P_HWPMC; 1127 PROC_UNLOCK(p); 1128 1129 if ((pp = pmc_find_process_descriptor(p, PMC_FLAG_ALLOCATE)) == NULL) { 1130 error = ENOMEM; 1131 goto fail; 1132 } 1133 1134 if (pp->pp_pmcs[ri].pp_pmc == pm) {/* already present at slot [ri] */ 1135 error = EEXIST; 1136 goto fail; 1137 } 1138 1139 if (pp->pp_pmcs[ri].pp_pmc != NULL) { 1140 error = EBUSY; 1141 goto fail; 1142 } 1143 1144 pmc_link_target_process(pm, pp); 1145 1146 if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)) && 1147 (pm->pm_flags & PMC_F_ATTACHED_TO_OWNER) == 0) 1148 pm->pm_flags |= PMC_F_NEEDS_LOGFILE; 1149 1150 pm->pm_flags |= PMC_F_ATTACH_DONE; /* mark as attached */ 1151 1152 /* issue an attach event to a configured log file */ 1153 if (pm->pm_owner->po_flags & PMC_PO_OWNS_LOGFILE) { 1154 if (p->p_flag & P_KPROC) { 1155 fullpath = kernelname; 1156 freepath = NULL; 1157 } else { 1158 pmc_getfilename(p->p_textvp, &fullpath, &freepath); 1159 pmclog_process_pmcattach(pm, p->p_pid, fullpath); 1160 } 1161 free(freepath, M_TEMP); 1162 if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm))) 1163 pmc_log_process_mappings(pm->pm_owner, p); 1164 } 1165 1166 return (0); 1167 fail: 1168 PROC_LOCK(p); 1169 p->p_flag &= ~P_HWPMC; 1170 PROC_UNLOCK(p); 1171 return (error); 1172 } 1173 1174 /* 1175 * Attach a process and optionally its children 1176 */ 1177 1178 static int 1179 pmc_attach_process(struct proc *p, struct pmc *pm) 1180 { 1181 int error; 1182 struct proc *top; 1183 1184 sx_assert(&pmc_sx, SX_XLOCKED); 1185 1186 PMCDBG5(PRC,ATT,1, "attach pm=%p ri=%d proc=%p (%d, %s)", pm, 1187 PMC_TO_ROWINDEX(pm), p, p->p_pid, p->p_comm); 1188 1189 1190 /* 1191 * If this PMC successfully allowed a GETMSR operation 1192 * in the past, disallow further ATTACHes. 1193 */ 1194 1195 if ((pm->pm_flags & PMC_PP_ENABLE_MSR_ACCESS) != 0) 1196 return EPERM; 1197 1198 if ((pm->pm_flags & PMC_F_DESCENDANTS) == 0) 1199 return pmc_attach_one_process(p, pm); 1200 1201 /* 1202 * Traverse all child processes, attaching them to 1203 * this PMC. 1204 */ 1205 1206 sx_slock(&proctree_lock); 1207 1208 top = p; 1209 1210 for (;;) { 1211 if ((error = pmc_attach_one_process(p, pm)) != 0) 1212 break; 1213 if (!LIST_EMPTY(&p->p_children)) 1214 p = LIST_FIRST(&p->p_children); 1215 else for (;;) { 1216 if (p == top) 1217 goto done; 1218 if (LIST_NEXT(p, p_sibling)) { 1219 p = LIST_NEXT(p, p_sibling); 1220 break; 1221 } 1222 p = p->p_pptr; 1223 } 1224 } 1225 1226 if (error) 1227 (void) pmc_detach_process(top, pm); 1228 1229 done: 1230 sx_sunlock(&proctree_lock); 1231 return error; 1232 } 1233 1234 /* 1235 * Detach a process from a PMC. If there are no other PMCs tracking 1236 * this process, remove the process structure from its hash table. If 1237 * 'flags' contains PMC_FLAG_REMOVE, then free the process structure. 1238 */ 1239 1240 static int 1241 pmc_detach_one_process(struct proc *p, struct pmc *pm, int flags) 1242 { 1243 int ri; 1244 struct pmc_process *pp; 1245 1246 sx_assert(&pmc_sx, SX_XLOCKED); 1247 1248 KASSERT(pm != NULL, 1249 ("[pmc,%d] null pm pointer", __LINE__)); 1250 1251 ri = PMC_TO_ROWINDEX(pm); 1252 1253 PMCDBG6(PRC,ATT,2, "detach-one pm=%p ri=%d proc=%p (%d, %s) flags=0x%x", 1254 pm, ri, p, p->p_pid, p->p_comm, flags); 1255 1256 if ((pp = pmc_find_process_descriptor(p, 0)) == NULL) 1257 return ESRCH; 1258 1259 if (pp->pp_pmcs[ri].pp_pmc != pm) 1260 return EINVAL; 1261 1262 pmc_unlink_target_process(pm, pp); 1263 1264 /* Issue a detach entry if a log file is configured */ 1265 if (pm->pm_owner->po_flags & PMC_PO_OWNS_LOGFILE) 1266 pmclog_process_pmcdetach(pm, p->p_pid); 1267 1268 /* 1269 * If there are no PMCs targeting this process, we remove its 1270 * descriptor from the target hash table and unset the P_HWPMC 1271 * flag in the struct proc. 1272 */ 1273 KASSERT(pp->pp_refcnt >= 0 && pp->pp_refcnt <= (int) md->pmd_npmc, 1274 ("[pmc,%d] Illegal refcnt %d for process struct %p", 1275 __LINE__, pp->pp_refcnt, pp)); 1276 1277 if (pp->pp_refcnt != 0) /* still a target of some PMC */ 1278 return 0; 1279 1280 pmc_remove_process_descriptor(pp); 1281 1282 if (flags & PMC_FLAG_REMOVE) 1283 pmc_destroy_process_descriptor(pp); 1284 1285 PROC_LOCK(p); 1286 p->p_flag &= ~P_HWPMC; 1287 PROC_UNLOCK(p); 1288 1289 return 0; 1290 } 1291 1292 /* 1293 * Detach a process and optionally its descendants from a PMC. 1294 */ 1295 1296 static int 1297 pmc_detach_process(struct proc *p, struct pmc *pm) 1298 { 1299 struct proc *top; 1300 1301 sx_assert(&pmc_sx, SX_XLOCKED); 1302 1303 PMCDBG5(PRC,ATT,1, "detach pm=%p ri=%d proc=%p (%d, %s)", pm, 1304 PMC_TO_ROWINDEX(pm), p, p->p_pid, p->p_comm); 1305 1306 if ((pm->pm_flags & PMC_F_DESCENDANTS) == 0) 1307 return pmc_detach_one_process(p, pm, PMC_FLAG_REMOVE); 1308 1309 /* 1310 * Traverse all children, detaching them from this PMC. We 1311 * ignore errors since we could be detaching a PMC from a 1312 * partially attached proc tree. 1313 */ 1314 1315 sx_slock(&proctree_lock); 1316 1317 top = p; 1318 1319 for (;;) { 1320 (void) pmc_detach_one_process(p, pm, PMC_FLAG_REMOVE); 1321 1322 if (!LIST_EMPTY(&p->p_children)) 1323 p = LIST_FIRST(&p->p_children); 1324 else for (;;) { 1325 if (p == top) 1326 goto done; 1327 if (LIST_NEXT(p, p_sibling)) { 1328 p = LIST_NEXT(p, p_sibling); 1329 break; 1330 } 1331 p = p->p_pptr; 1332 } 1333 } 1334 1335 done: 1336 sx_sunlock(&proctree_lock); 1337 1338 if (LIST_EMPTY(&pm->pm_targets)) 1339 pm->pm_flags &= ~PMC_F_ATTACH_DONE; 1340 1341 return 0; 1342 } 1343 1344 1345 /* 1346 * Thread context switch IN 1347 */ 1348 1349 static void 1350 pmc_process_csw_in(struct thread *td) 1351 { 1352 int cpu; 1353 unsigned int adjri, ri; 1354 struct pmc *pm; 1355 struct proc *p; 1356 struct pmc_cpu *pc; 1357 struct pmc_hw *phw; 1358 pmc_value_t newvalue; 1359 struct pmc_process *pp; 1360 struct pmc_thread *pt; 1361 struct pmc_classdep *pcd; 1362 1363 p = td->td_proc; 1364 pt = NULL; 1365 if ((pp = pmc_find_process_descriptor(p, PMC_FLAG_NONE)) == NULL) 1366 return; 1367 1368 KASSERT(pp->pp_proc == td->td_proc, 1369 ("[pmc,%d] not my thread state", __LINE__)); 1370 1371 critical_enter(); /* no preemption from this point */ 1372 1373 cpu = PCPU_GET(cpuid); /* td->td_oncpu is invalid */ 1374 1375 PMCDBG5(CSW,SWI,1, "cpu=%d proc=%p (%d, %s) pp=%p", cpu, p, 1376 p->p_pid, p->p_comm, pp); 1377 1378 KASSERT(cpu >= 0 && cpu < pmc_cpu_max(), 1379 ("[pmc,%d] weird CPU id %d", __LINE__, cpu)); 1380 1381 pc = pmc_pcpu[cpu]; 1382 1383 for (ri = 0; ri < md->pmd_npmc; ri++) { 1384 1385 if ((pm = pp->pp_pmcs[ri].pp_pmc) == NULL) 1386 continue; 1387 1388 KASSERT(PMC_IS_VIRTUAL_MODE(PMC_TO_MODE(pm)), 1389 ("[pmc,%d] Target PMC in non-virtual mode (%d)", 1390 __LINE__, PMC_TO_MODE(pm))); 1391 1392 KASSERT(PMC_TO_ROWINDEX(pm) == ri, 1393 ("[pmc,%d] Row index mismatch pmc %d != ri %d", 1394 __LINE__, PMC_TO_ROWINDEX(pm), ri)); 1395 1396 /* 1397 * Only PMCs that are marked as 'RUNNING' need 1398 * be placed on hardware. 1399 */ 1400 1401 if (pm->pm_state != PMC_STATE_RUNNING) 1402 continue; 1403 1404 /* increment PMC runcount */ 1405 counter_u64_add(pm->pm_runcount, 1); 1406 1407 /* configure the HWPMC we are going to use. */ 1408 pcd = pmc_ri_to_classdep(md, ri, &adjri); 1409 pcd->pcd_config_pmc(cpu, adjri, pm); 1410 1411 phw = pc->pc_hwpmcs[ri]; 1412 1413 KASSERT(phw != NULL, 1414 ("[pmc,%d] null hw pointer", __LINE__)); 1415 1416 KASSERT(phw->phw_pmc == pm, 1417 ("[pmc,%d] hw->pmc %p != pmc %p", __LINE__, 1418 phw->phw_pmc, pm)); 1419 1420 /* 1421 * Write out saved value and start the PMC. 1422 * 1423 * Sampling PMCs use a per-thread value, while 1424 * counting mode PMCs use a per-pmc value that is 1425 * inherited across descendants. 1426 */ 1427 if (PMC_TO_MODE(pm) == PMC_MODE_TS) { 1428 if (pt == NULL) 1429 pt = pmc_find_thread_descriptor(pp, td, 1430 PMC_FLAG_NONE); 1431 1432 KASSERT(pt != NULL, 1433 ("[pmc,%d] No thread found for td=%p", __LINE__, 1434 td)); 1435 1436 mtx_pool_lock_spin(pmc_mtxpool, pm); 1437 1438 /* 1439 * If we have a thread descriptor, use the per-thread 1440 * counter in the descriptor. If not, we will use 1441 * a per-process counter. 1442 * 1443 * TODO: Remove the per-process "safety net" once 1444 * we have thoroughly tested that we don't hit the 1445 * above assert. 1446 */ 1447 if (pt != NULL) { 1448 if (pt->pt_pmcs[ri].pt_pmcval > 0) 1449 newvalue = pt->pt_pmcs[ri].pt_pmcval; 1450 else 1451 newvalue = pm->pm_sc.pm_reloadcount; 1452 } else { 1453 /* 1454 * Use the saved value calculated after the most 1455 * recent time a thread using the shared counter 1456 * switched out. Reset the saved count in case 1457 * another thread from this process switches in 1458 * before any threads switch out. 1459 */ 1460 1461 newvalue = pp->pp_pmcs[ri].pp_pmcval; 1462 pp->pp_pmcs[ri].pp_pmcval = 1463 pm->pm_sc.pm_reloadcount; 1464 } 1465 mtx_pool_unlock_spin(pmc_mtxpool, pm); 1466 KASSERT(newvalue > 0 && newvalue <= 1467 pm->pm_sc.pm_reloadcount, 1468 ("[pmc,%d] pmcval outside of expected range cpu=%d " 1469 "ri=%d pmcval=%jx pm_reloadcount=%jx", __LINE__, 1470 cpu, ri, newvalue, pm->pm_sc.pm_reloadcount)); 1471 } else { 1472 KASSERT(PMC_TO_MODE(pm) == PMC_MODE_TC, 1473 ("[pmc,%d] illegal mode=%d", __LINE__, 1474 PMC_TO_MODE(pm))); 1475 mtx_pool_lock_spin(pmc_mtxpool, pm); 1476 newvalue = PMC_PCPU_SAVED(cpu, ri) = 1477 pm->pm_gv.pm_savedvalue; 1478 mtx_pool_unlock_spin(pmc_mtxpool, pm); 1479 } 1480 1481 PMCDBG3(CSW,SWI,1,"cpu=%d ri=%d new=%jd", cpu, ri, newvalue); 1482 1483 pcd->pcd_write_pmc(cpu, adjri, newvalue); 1484 1485 /* If a sampling mode PMC, reset stalled state. */ 1486 if (PMC_TO_MODE(pm) == PMC_MODE_TS) 1487 pm->pm_pcpu_state[cpu].pps_stalled = 0; 1488 1489 /* Indicate that we desire this to run. */ 1490 pm->pm_pcpu_state[cpu].pps_cpustate = 1; 1491 1492 /* Start the PMC. */ 1493 pcd->pcd_start_pmc(cpu, adjri); 1494 } 1495 1496 /* 1497 * perform any other architecture/cpu dependent thread 1498 * switch-in actions. 1499 */ 1500 1501 (void) (*md->pmd_switch_in)(pc, pp); 1502 1503 critical_exit(); 1504 1505 } 1506 1507 /* 1508 * Thread context switch OUT. 1509 */ 1510 1511 static void 1512 pmc_process_csw_out(struct thread *td) 1513 { 1514 int cpu; 1515 int64_t tmp; 1516 struct pmc *pm; 1517 struct proc *p; 1518 enum pmc_mode mode; 1519 struct pmc_cpu *pc; 1520 pmc_value_t newvalue; 1521 unsigned int adjri, ri; 1522 struct pmc_process *pp; 1523 struct pmc_thread *pt = NULL; 1524 struct pmc_classdep *pcd; 1525 1526 1527 /* 1528 * Locate our process descriptor; this may be NULL if 1529 * this process is exiting and we have already removed 1530 * the process from the target process table. 1531 * 1532 * Note that due to kernel preemption, multiple 1533 * context switches may happen while the process is 1534 * exiting. 1535 * 1536 * Note also that if the target process cannot be 1537 * found we still need to deconfigure any PMCs that 1538 * are currently running on hardware. 1539 */ 1540 1541 p = td->td_proc; 1542 pp = pmc_find_process_descriptor(p, PMC_FLAG_NONE); 1543 1544 /* 1545 * save PMCs 1546 */ 1547 1548 critical_enter(); 1549 1550 cpu = PCPU_GET(cpuid); /* td->td_oncpu is invalid */ 1551 1552 PMCDBG5(CSW,SWO,1, "cpu=%d proc=%p (%d, %s) pp=%p", cpu, p, 1553 p->p_pid, p->p_comm, pp); 1554 1555 KASSERT(cpu >= 0 && cpu < pmc_cpu_max(), 1556 ("[pmc,%d weird CPU id %d", __LINE__, cpu)); 1557 1558 pc = pmc_pcpu[cpu]; 1559 1560 /* 1561 * When a PMC gets unlinked from a target PMC, it will 1562 * be removed from the target's pp_pmc[] array. 1563 * 1564 * However, on a MP system, the target could have been 1565 * executing on another CPU at the time of the unlink. 1566 * So, at context switch OUT time, we need to look at 1567 * the hardware to determine if a PMC is scheduled on 1568 * it. 1569 */ 1570 1571 for (ri = 0; ri < md->pmd_npmc; ri++) { 1572 1573 pcd = pmc_ri_to_classdep(md, ri, &adjri); 1574 pm = NULL; 1575 (void) (*pcd->pcd_get_config)(cpu, adjri, &pm); 1576 1577 if (pm == NULL) /* nothing at this row index */ 1578 continue; 1579 1580 mode = PMC_TO_MODE(pm); 1581 if (!PMC_IS_VIRTUAL_MODE(mode)) 1582 continue; /* not a process virtual PMC */ 1583 1584 KASSERT(PMC_TO_ROWINDEX(pm) == ri, 1585 ("[pmc,%d] ri mismatch pmc(%d) ri(%d)", 1586 __LINE__, PMC_TO_ROWINDEX(pm), ri)); 1587 1588 /* 1589 * Change desired state, and then stop if not stalled. 1590 * This two-step dance should avoid race conditions where 1591 * an interrupt re-enables the PMC after this code has 1592 * already checked the pm_stalled flag. 1593 */ 1594 pm->pm_pcpu_state[cpu].pps_cpustate = 0; 1595 if (pm->pm_pcpu_state[cpu].pps_stalled == 0) 1596 pcd->pcd_stop_pmc(cpu, adjri); 1597 1598 /* reduce this PMC's runcount */ 1599 counter_u64_add(pm->pm_runcount, -1); 1600 1601 /* 1602 * If this PMC is associated with this process, 1603 * save the reading. 1604 */ 1605 1606 if (pm->pm_state != PMC_STATE_DELETED && pp != NULL && 1607 pp->pp_pmcs[ri].pp_pmc != NULL) { 1608 KASSERT(pm == pp->pp_pmcs[ri].pp_pmc, 1609 ("[pmc,%d] pm %p != pp_pmcs[%d] %p", __LINE__, 1610 pm, ri, pp->pp_pmcs[ri].pp_pmc)); 1611 1612 KASSERT(pp->pp_refcnt > 0, 1613 ("[pmc,%d] pp refcnt = %d", __LINE__, 1614 pp->pp_refcnt)); 1615 1616 pcd->pcd_read_pmc(cpu, adjri, &newvalue); 1617 1618 if (mode == PMC_MODE_TS) { 1619 PMCDBG3(CSW,SWO,1,"cpu=%d ri=%d val=%jd (samp)", 1620 cpu, ri, newvalue); 1621 1622 if (pt == NULL) 1623 pt = pmc_find_thread_descriptor(pp, td, 1624 PMC_FLAG_NONE); 1625 1626 KASSERT(pt != NULL, 1627 ("[pmc,%d] No thread found for td=%p", 1628 __LINE__, td)); 1629 1630 mtx_pool_lock_spin(pmc_mtxpool, pm); 1631 1632 /* 1633 * If we have a thread descriptor, save the 1634 * per-thread counter in the descriptor. If not, 1635 * we will update the per-process counter. 1636 * 1637 * TODO: Remove the per-process "safety net" 1638 * once we have thoroughly tested that we 1639 * don't hit the above assert. 1640 */ 1641 if (pt != NULL) 1642 pt->pt_pmcs[ri].pt_pmcval = newvalue; 1643 else { 1644 /* 1645 * For sampling process-virtual PMCs, 1646 * newvalue is the number of events to 1647 * be seen until the next sampling 1648 * interrupt. We can just add the events 1649 * left from this invocation to the 1650 * counter, then adjust in case we 1651 * overflow our range. 1652 * 1653 * (Recall that we reload the counter 1654 * every time we use it.) 1655 */ 1656 pp->pp_pmcs[ri].pp_pmcval += newvalue; 1657 if (pp->pp_pmcs[ri].pp_pmcval > 1658 pm->pm_sc.pm_reloadcount) 1659 pp->pp_pmcs[ri].pp_pmcval -= 1660 pm->pm_sc.pm_reloadcount; 1661 } 1662 mtx_pool_unlock_spin(pmc_mtxpool, pm); 1663 } else { 1664 tmp = newvalue - PMC_PCPU_SAVED(cpu,ri); 1665 1666 PMCDBG3(CSW,SWO,1,"cpu=%d ri=%d tmp=%jd (count)", 1667 cpu, ri, tmp); 1668 1669 /* 1670 * For counting process-virtual PMCs, 1671 * we expect the count to be 1672 * increasing monotonically, modulo a 64 1673 * bit wraparound. 1674 */ 1675 KASSERT(tmp >= 0, 1676 ("[pmc,%d] negative increment cpu=%d " 1677 "ri=%d newvalue=%jx saved=%jx " 1678 "incr=%jx", __LINE__, cpu, ri, 1679 newvalue, PMC_PCPU_SAVED(cpu,ri), tmp)); 1680 1681 mtx_pool_lock_spin(pmc_mtxpool, pm); 1682 pm->pm_gv.pm_savedvalue += tmp; 1683 pp->pp_pmcs[ri].pp_pmcval += tmp; 1684 mtx_pool_unlock_spin(pmc_mtxpool, pm); 1685 1686 if (pm->pm_flags & PMC_F_LOG_PROCCSW) 1687 pmclog_process_proccsw(pm, pp, tmp, td); 1688 } 1689 } 1690 1691 /* mark hardware as free */ 1692 pcd->pcd_config_pmc(cpu, adjri, NULL); 1693 } 1694 1695 /* 1696 * perform any other architecture/cpu dependent thread 1697 * switch out functions. 1698 */ 1699 1700 (void) (*md->pmd_switch_out)(pc, pp); 1701 1702 critical_exit(); 1703 } 1704 1705 /* 1706 * A new thread for a process. 1707 */ 1708 static void 1709 pmc_process_thread_add(struct thread *td) 1710 { 1711 struct pmc_process *pmc; 1712 1713 pmc = pmc_find_process_descriptor(td->td_proc, PMC_FLAG_NONE); 1714 if (pmc != NULL) 1715 pmc_find_thread_descriptor(pmc, td, PMC_FLAG_ALLOCATE); 1716 } 1717 1718 /* 1719 * A thread delete for a process. 1720 */ 1721 static void 1722 pmc_process_thread_delete(struct thread *td) 1723 { 1724 struct pmc_process *pmc; 1725 1726 pmc = pmc_find_process_descriptor(td->td_proc, PMC_FLAG_NONE); 1727 if (pmc != NULL) 1728 pmc_thread_descriptor_pool_free(pmc_find_thread_descriptor(pmc, 1729 td, PMC_FLAG_REMOVE)); 1730 } 1731 1732 /* 1733 * A userret() call for a thread. 1734 */ 1735 static void 1736 pmc_process_thread_userret(struct thread *td) 1737 { 1738 sched_pin(); 1739 pmc_capture_user_callchain(curcpu, PMC_UR, td->td_frame); 1740 sched_unpin(); 1741 } 1742 1743 /* 1744 * A mapping change for a process. 1745 */ 1746 1747 static void 1748 pmc_process_mmap(struct thread *td, struct pmckern_map_in *pkm) 1749 { 1750 int ri; 1751 pid_t pid; 1752 char *fullpath, *freepath; 1753 const struct pmc *pm; 1754 struct pmc_owner *po; 1755 const struct pmc_process *pp; 1756 1757 freepath = fullpath = NULL; 1758 MPASS(!in_epoch(global_epoch_preempt)); 1759 pmc_getfilename((struct vnode *) pkm->pm_file, &fullpath, &freepath); 1760 1761 pid = td->td_proc->p_pid; 1762 1763 PMC_EPOCH_ENTER(); 1764 /* Inform owners of all system-wide sampling PMCs. */ 1765 CK_LIST_FOREACH(po, &pmc_ss_owners, po_ssnext) 1766 if (po->po_flags & PMC_PO_OWNS_LOGFILE) 1767 pmclog_process_map_in(po, pid, pkm->pm_address, fullpath); 1768 1769 if ((pp = pmc_find_process_descriptor(td->td_proc, 0)) == NULL) 1770 goto done; 1771 1772 /* 1773 * Inform sampling PMC owners tracking this process. 1774 */ 1775 for (ri = 0; ri < md->pmd_npmc; ri++) 1776 if ((pm = pp->pp_pmcs[ri].pp_pmc) != NULL && 1777 PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm))) 1778 pmclog_process_map_in(pm->pm_owner, 1779 pid, pkm->pm_address, fullpath); 1780 1781 done: 1782 if (freepath) 1783 free(freepath, M_TEMP); 1784 PMC_EPOCH_EXIT(); 1785 } 1786 1787 1788 /* 1789 * Log an munmap request. 1790 */ 1791 1792 static void 1793 pmc_process_munmap(struct thread *td, struct pmckern_map_out *pkm) 1794 { 1795 int ri; 1796 pid_t pid; 1797 struct pmc_owner *po; 1798 const struct pmc *pm; 1799 const struct pmc_process *pp; 1800 1801 pid = td->td_proc->p_pid; 1802 1803 PMC_EPOCH_ENTER(); 1804 CK_LIST_FOREACH(po, &pmc_ss_owners, po_ssnext) 1805 if (po->po_flags & PMC_PO_OWNS_LOGFILE) 1806 pmclog_process_map_out(po, pid, pkm->pm_address, 1807 pkm->pm_address + pkm->pm_size); 1808 PMC_EPOCH_EXIT(); 1809 1810 if ((pp = pmc_find_process_descriptor(td->td_proc, 0)) == NULL) 1811 return; 1812 1813 for (ri = 0; ri < md->pmd_npmc; ri++) 1814 if ((pm = pp->pp_pmcs[ri].pp_pmc) != NULL && 1815 PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm))) 1816 pmclog_process_map_out(pm->pm_owner, pid, 1817 pkm->pm_address, pkm->pm_address + pkm->pm_size); 1818 } 1819 1820 /* 1821 * Log mapping information about the kernel. 1822 */ 1823 1824 static void 1825 pmc_log_kernel_mappings(struct pmc *pm) 1826 { 1827 struct pmc_owner *po; 1828 struct pmckern_map_in *km, *kmbase; 1829 1830 MPASS(in_epoch(global_epoch_preempt) || sx_xlocked(&pmc_sx)); 1831 KASSERT(PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)), 1832 ("[pmc,%d] non-sampling PMC (%p) desires mapping information", 1833 __LINE__, (void *) pm)); 1834 1835 po = pm->pm_owner; 1836 1837 if (po->po_flags & PMC_PO_INITIAL_MAPPINGS_DONE) 1838 return; 1839 if (PMC_TO_MODE(pm) == PMC_MODE_SS) 1840 pmc_process_allproc(pm); 1841 /* 1842 * Log the current set of kernel modules. 1843 */ 1844 kmbase = linker_hwpmc_list_objects(); 1845 for (km = kmbase; km->pm_file != NULL; km++) { 1846 PMCDBG2(LOG,REG,1,"%s %p", (char *) km->pm_file, 1847 (void *) km->pm_address); 1848 pmclog_process_map_in(po, (pid_t) -1, km->pm_address, 1849 km->pm_file); 1850 } 1851 free(kmbase, M_LINKER); 1852 1853 po->po_flags |= PMC_PO_INITIAL_MAPPINGS_DONE; 1854 } 1855 1856 /* 1857 * Log the mappings for a single process. 1858 */ 1859 1860 static void 1861 pmc_log_process_mappings(struct pmc_owner *po, struct proc *p) 1862 { 1863 vm_map_t map; 1864 struct vnode *vp; 1865 struct vmspace *vm; 1866 vm_map_entry_t entry; 1867 vm_offset_t last_end; 1868 u_int last_timestamp; 1869 struct vnode *last_vp; 1870 vm_offset_t start_addr; 1871 vm_object_t obj, lobj, tobj; 1872 char *fullpath, *freepath; 1873 1874 last_vp = NULL; 1875 last_end = (vm_offset_t) 0; 1876 fullpath = freepath = NULL; 1877 1878 if ((vm = vmspace_acquire_ref(p)) == NULL) 1879 return; 1880 1881 map = &vm->vm_map; 1882 vm_map_lock_read(map); 1883 1884 for (entry = map->header.next; entry != &map->header; entry = entry->next) { 1885 1886 if (entry == NULL) { 1887 PMCDBG2(LOG,OPS,2, "hwpmc: vm_map entry unexpectedly " 1888 "NULL! pid=%d vm_map=%p\n", p->p_pid, map); 1889 break; 1890 } 1891 1892 /* 1893 * We only care about executable map entries. 1894 */ 1895 if ((entry->eflags & MAP_ENTRY_IS_SUB_MAP) || 1896 !(entry->protection & VM_PROT_EXECUTE) || 1897 (entry->object.vm_object == NULL)) { 1898 continue; 1899 } 1900 1901 obj = entry->object.vm_object; 1902 VM_OBJECT_RLOCK(obj); 1903 1904 /* 1905 * Walk the backing_object list to find the base 1906 * (non-shadowed) vm_object. 1907 */ 1908 for (lobj = tobj = obj; tobj != NULL; tobj = tobj->backing_object) { 1909 if (tobj != obj) 1910 VM_OBJECT_RLOCK(tobj); 1911 if (lobj != obj) 1912 VM_OBJECT_RUNLOCK(lobj); 1913 lobj = tobj; 1914 } 1915 1916 /* 1917 * At this point lobj is the base vm_object and it is locked. 1918 */ 1919 if (lobj == NULL) { 1920 PMCDBG3(LOG,OPS,2, "hwpmc: lobj unexpectedly NULL! pid=%d " 1921 "vm_map=%p vm_obj=%p\n", p->p_pid, map, obj); 1922 VM_OBJECT_RUNLOCK(obj); 1923 continue; 1924 } 1925 1926 vp = vm_object_vnode(lobj); 1927 if (vp == NULL) { 1928 if (lobj != obj) 1929 VM_OBJECT_RUNLOCK(lobj); 1930 VM_OBJECT_RUNLOCK(obj); 1931 continue; 1932 } 1933 1934 /* 1935 * Skip contiguous regions that point to the same 1936 * vnode, so we don't emit redundant MAP-IN 1937 * directives. 1938 */ 1939 if (entry->start == last_end && vp == last_vp) { 1940 last_end = entry->end; 1941 if (lobj != obj) 1942 VM_OBJECT_RUNLOCK(lobj); 1943 VM_OBJECT_RUNLOCK(obj); 1944 continue; 1945 } 1946 1947 /* 1948 * We don't want to keep the proc's vm_map or this 1949 * vm_object locked while we walk the pathname, since 1950 * vn_fullpath() can sleep. However, if we drop the 1951 * lock, it's possible for concurrent activity to 1952 * modify the vm_map list. To protect against this, 1953 * we save the vm_map timestamp before we release the 1954 * lock, and check it after we reacquire the lock 1955 * below. 1956 */ 1957 start_addr = entry->start; 1958 last_end = entry->end; 1959 last_timestamp = map->timestamp; 1960 vm_map_unlock_read(map); 1961 1962 vref(vp); 1963 if (lobj != obj) 1964 VM_OBJECT_RUNLOCK(lobj); 1965 1966 VM_OBJECT_RUNLOCK(obj); 1967 1968 freepath = NULL; 1969 pmc_getfilename(vp, &fullpath, &freepath); 1970 last_vp = vp; 1971 1972 vrele(vp); 1973 1974 vp = NULL; 1975 pmclog_process_map_in(po, p->p_pid, start_addr, fullpath); 1976 if (freepath) 1977 free(freepath, M_TEMP); 1978 1979 vm_map_lock_read(map); 1980 1981 /* 1982 * If our saved timestamp doesn't match, this means 1983 * that the vm_map was modified out from under us and 1984 * we can't trust our current "entry" pointer. Do a 1985 * new lookup for this entry. If there is no entry 1986 * for this address range, vm_map_lookup_entry() will 1987 * return the previous one, so we always want to go to 1988 * entry->next on the next loop iteration. 1989 * 1990 * There is an edge condition here that can occur if 1991 * there is no entry at or before this address. In 1992 * this situation, vm_map_lookup_entry returns 1993 * &map->header, which would cause our loop to abort 1994 * without processing the rest of the map. However, 1995 * in practice this will never happen for process 1996 * vm_map. This is because the executable's text 1997 * segment is the first mapping in the proc's address 1998 * space, and this mapping is never removed until the 1999 * process exits, so there will always be a non-header 2000 * entry at or before the requested address for 2001 * vm_map_lookup_entry to return. 2002 */ 2003 if (map->timestamp != last_timestamp) 2004 vm_map_lookup_entry(map, last_end - 1, &entry); 2005 } 2006 2007 vm_map_unlock_read(map); 2008 vmspace_free(vm); 2009 return; 2010 } 2011 2012 /* 2013 * Log mappings for all processes in the system. 2014 */ 2015 2016 static void 2017 pmc_log_all_process_mappings(struct pmc_owner *po) 2018 { 2019 struct proc *p, *top; 2020 2021 sx_assert(&pmc_sx, SX_XLOCKED); 2022 2023 if ((p = pfind(1)) == NULL) 2024 panic("[pmc,%d] Cannot find init", __LINE__); 2025 2026 PROC_UNLOCK(p); 2027 2028 sx_slock(&proctree_lock); 2029 2030 top = p; 2031 2032 for (;;) { 2033 pmc_log_process_mappings(po, p); 2034 if (!LIST_EMPTY(&p->p_children)) 2035 p = LIST_FIRST(&p->p_children); 2036 else for (;;) { 2037 if (p == top) 2038 goto done; 2039 if (LIST_NEXT(p, p_sibling)) { 2040 p = LIST_NEXT(p, p_sibling); 2041 break; 2042 } 2043 p = p->p_pptr; 2044 } 2045 } 2046 done: 2047 sx_sunlock(&proctree_lock); 2048 } 2049 2050 /* 2051 * The 'hook' invoked from the kernel proper 2052 */ 2053 2054 2055 #ifdef HWPMC_DEBUG 2056 const char *pmc_hooknames[] = { 2057 /* these strings correspond to PMC_FN_* in <sys/pmckern.h> */ 2058 "", 2059 "EXEC", 2060 "CSW-IN", 2061 "CSW-OUT", 2062 "SAMPLE", 2063 "UNUSED1", 2064 "UNUSED2", 2065 "MMAP", 2066 "MUNMAP", 2067 "CALLCHAIN-NMI", 2068 "CALLCHAIN-SOFT", 2069 "SOFTSAMPLING", 2070 "THR-CREATE", 2071 "THR-EXIT", 2072 "THR-USERRET", 2073 "THR-CREATE-LOG", 2074 "THR-EXIT-LOG", 2075 "PROC-CREATE-LOG" 2076 }; 2077 #endif 2078 2079 static int 2080 pmc_hook_handler(struct thread *td, int function, void *arg) 2081 { 2082 int cpu; 2083 2084 PMCDBG4(MOD,PMH,1, "hook td=%p func=%d \"%s\" arg=%p", td, function, 2085 pmc_hooknames[function], arg); 2086 2087 switch (function) 2088 { 2089 2090 /* 2091 * Process exec() 2092 */ 2093 2094 case PMC_FN_PROCESS_EXEC: 2095 { 2096 char *fullpath, *freepath; 2097 unsigned int ri; 2098 int is_using_hwpmcs; 2099 struct pmc *pm; 2100 struct proc *p; 2101 struct pmc_owner *po; 2102 struct pmc_process *pp; 2103 struct pmckern_procexec *pk; 2104 2105 sx_assert(&pmc_sx, SX_XLOCKED); 2106 2107 p = td->td_proc; 2108 pmc_getfilename(p->p_textvp, &fullpath, &freepath); 2109 2110 pk = (struct pmckern_procexec *) arg; 2111 2112 PMC_EPOCH_ENTER(); 2113 /* Inform owners of SS mode PMCs of the exec event. */ 2114 CK_LIST_FOREACH(po, &pmc_ss_owners, po_ssnext) 2115 if (po->po_flags & PMC_PO_OWNS_LOGFILE) 2116 pmclog_process_procexec(po, PMC_ID_INVALID, 2117 p->p_pid, pk->pm_entryaddr, fullpath); 2118 PMC_EPOCH_EXIT(); 2119 2120 PROC_LOCK(p); 2121 is_using_hwpmcs = p->p_flag & P_HWPMC; 2122 PROC_UNLOCK(p); 2123 2124 if (!is_using_hwpmcs) { 2125 if (freepath) 2126 free(freepath, M_TEMP); 2127 break; 2128 } 2129 2130 /* 2131 * PMCs are not inherited across an exec(): remove any 2132 * PMCs that this process is the owner of. 2133 */ 2134 2135 if ((po = pmc_find_owner_descriptor(p)) != NULL) { 2136 pmc_remove_owner(po); 2137 pmc_destroy_owner_descriptor(po); 2138 } 2139 2140 /* 2141 * If the process being exec'ed is not the target of any 2142 * PMC, we are done. 2143 */ 2144 if ((pp = pmc_find_process_descriptor(p, 0)) == NULL) { 2145 if (freepath) 2146 free(freepath, M_TEMP); 2147 break; 2148 } 2149 2150 /* 2151 * Log the exec event to all monitoring owners. Skip 2152 * owners who have already received the event because 2153 * they had system sampling PMCs active. 2154 */ 2155 for (ri = 0; ri < md->pmd_npmc; ri++) 2156 if ((pm = pp->pp_pmcs[ri].pp_pmc) != NULL) { 2157 po = pm->pm_owner; 2158 if (po->po_sscount == 0 && 2159 po->po_flags & PMC_PO_OWNS_LOGFILE) 2160 pmclog_process_procexec(po, pm->pm_id, 2161 p->p_pid, pk->pm_entryaddr, 2162 fullpath); 2163 } 2164 2165 if (freepath) 2166 free(freepath, M_TEMP); 2167 2168 2169 PMCDBG4(PRC,EXC,1, "exec proc=%p (%d, %s) cred-changed=%d", 2170 p, p->p_pid, p->p_comm, pk->pm_credentialschanged); 2171 2172 if (pk->pm_credentialschanged == 0) /* no change */ 2173 break; 2174 2175 /* 2176 * If the newly exec()'ed process has a different credential 2177 * than before, allow it to be the target of a PMC only if 2178 * the PMC's owner has sufficient privilege. 2179 */ 2180 2181 for (ri = 0; ri < md->pmd_npmc; ri++) 2182 if ((pm = pp->pp_pmcs[ri].pp_pmc) != NULL) 2183 if (pmc_can_attach(pm, td->td_proc) != 0) 2184 pmc_detach_one_process(td->td_proc, 2185 pm, PMC_FLAG_NONE); 2186 2187 KASSERT(pp->pp_refcnt >= 0 && pp->pp_refcnt <= (int) md->pmd_npmc, 2188 ("[pmc,%d] Illegal ref count %d on pp %p", __LINE__, 2189 pp->pp_refcnt, pp)); 2190 2191 /* 2192 * If this process is no longer the target of any 2193 * PMCs, we can remove the process entry and free 2194 * up space. 2195 */ 2196 2197 if (pp->pp_refcnt == 0) { 2198 pmc_remove_process_descriptor(pp); 2199 pmc_destroy_process_descriptor(pp); 2200 break; 2201 } 2202 2203 } 2204 break; 2205 2206 case PMC_FN_CSW_IN: 2207 pmc_process_csw_in(td); 2208 break; 2209 2210 case PMC_FN_CSW_OUT: 2211 pmc_process_csw_out(td); 2212 break; 2213 2214 /* 2215 * Process accumulated PC samples. 2216 * 2217 * This function is expected to be called by hardclock() for 2218 * each CPU that has accumulated PC samples. 2219 * 2220 * This function is to be executed on the CPU whose samples 2221 * are being processed. 2222 */ 2223 case PMC_FN_DO_SAMPLES: 2224 2225 /* 2226 * Clear the cpu specific bit in the CPU mask before 2227 * do the rest of the processing. If the NMI handler 2228 * gets invoked after the "atomic_clear_int()" call 2229 * below but before "pmc_process_samples()" gets 2230 * around to processing the interrupt, then we will 2231 * come back here at the next hardclock() tick (and 2232 * may find nothing to do if "pmc_process_samples()" 2233 * had already processed the interrupt). We don't 2234 * lose the interrupt sample. 2235 */ 2236 DPCPU_SET(pmc_sampled, 0); 2237 cpu = PCPU_GET(cpuid); 2238 pmc_process_samples(cpu, PMC_HR); 2239 pmc_process_samples(cpu, PMC_SR); 2240 pmc_process_samples(cpu, PMC_UR); 2241 break; 2242 2243 case PMC_FN_MMAP: 2244 pmc_process_mmap(td, (struct pmckern_map_in *) arg); 2245 break; 2246 2247 case PMC_FN_MUNMAP: 2248 MPASS(in_epoch(global_epoch_preempt) || sx_xlocked(&pmc_sx)); 2249 pmc_process_munmap(td, (struct pmckern_map_out *) arg); 2250 break; 2251 2252 case PMC_FN_PROC_CREATE_LOG: 2253 pmc_process_proccreate((struct proc *)arg); 2254 break; 2255 2256 case PMC_FN_USER_CALLCHAIN: 2257 /* 2258 * Record a call chain. 2259 */ 2260 KASSERT(td == curthread, ("[pmc,%d] td != curthread", 2261 __LINE__)); 2262 2263 pmc_capture_user_callchain(PCPU_GET(cpuid), PMC_HR, 2264 (struct trapframe *) arg); 2265 2266 KASSERT(td->td_pinned == 1, 2267 ("[pmc,%d] invalid td_pinned value", __LINE__)); 2268 sched_unpin(); /* Can migrate safely now. */ 2269 2270 td->td_pflags &= ~TDP_CALLCHAIN; 2271 break; 2272 2273 case PMC_FN_USER_CALLCHAIN_SOFT: 2274 /* 2275 * Record a call chain. 2276 */ 2277 KASSERT(td == curthread, ("[pmc,%d] td != curthread", 2278 __LINE__)); 2279 2280 cpu = PCPU_GET(cpuid); 2281 pmc_capture_user_callchain(cpu, PMC_SR, 2282 (struct trapframe *) arg); 2283 2284 KASSERT(td->td_pinned == 1, 2285 ("[pmc,%d] invalid td_pinned value", __LINE__)); 2286 2287 sched_unpin(); /* Can migrate safely now. */ 2288 2289 td->td_pflags &= ~TDP_CALLCHAIN; 2290 break; 2291 2292 case PMC_FN_SOFT_SAMPLING: 2293 /* 2294 * Call soft PMC sampling intr. 2295 */ 2296 pmc_soft_intr((struct pmckern_soft *) arg); 2297 break; 2298 2299 case PMC_FN_THR_CREATE: 2300 pmc_process_thread_add(td); 2301 pmc_process_threadcreate(td); 2302 break; 2303 2304 case PMC_FN_THR_CREATE_LOG: 2305 pmc_process_threadcreate(td); 2306 break; 2307 2308 case PMC_FN_THR_EXIT: 2309 KASSERT(td == curthread, ("[pmc,%d] td != curthread", 2310 __LINE__)); 2311 pmc_process_thread_delete(td); 2312 pmc_process_threadexit(td); 2313 break; 2314 case PMC_FN_THR_EXIT_LOG: 2315 pmc_process_threadexit(td); 2316 break; 2317 case PMC_FN_THR_USERRET: 2318 KASSERT(td == curthread, ("[pmc,%d] td != curthread", 2319 __LINE__)); 2320 pmc_process_thread_userret(td); 2321 break; 2322 2323 default: 2324 #ifdef HWPMC_DEBUG 2325 KASSERT(0, ("[pmc,%d] unknown hook %d\n", __LINE__, function)); 2326 #endif 2327 break; 2328 2329 } 2330 2331 return 0; 2332 } 2333 2334 /* 2335 * allocate a 'struct pmc_owner' descriptor in the owner hash table. 2336 */ 2337 2338 static struct pmc_owner * 2339 pmc_allocate_owner_descriptor(struct proc *p) 2340 { 2341 uint32_t hindex; 2342 struct pmc_owner *po; 2343 struct pmc_ownerhash *poh; 2344 2345 hindex = PMC_HASH_PTR(p, pmc_ownerhashmask); 2346 poh = &pmc_ownerhash[hindex]; 2347 2348 /* allocate space for N pointers and one descriptor struct */ 2349 po = malloc(sizeof(struct pmc_owner), M_PMC, M_WAITOK|M_ZERO); 2350 po->po_owner = p; 2351 LIST_INSERT_HEAD(poh, po, po_next); /* insert into hash table */ 2352 2353 TAILQ_INIT(&po->po_logbuffers); 2354 mtx_init(&po->po_mtx, "pmc-owner-mtx", "pmc-per-proc", MTX_SPIN); 2355 2356 PMCDBG4(OWN,ALL,1, "allocate-owner proc=%p (%d, %s) pmc-owner=%p", 2357 p, p->p_pid, p->p_comm, po); 2358 2359 return po; 2360 } 2361 2362 static void 2363 pmc_destroy_owner_descriptor(struct pmc_owner *po) 2364 { 2365 2366 PMCDBG4(OWN,REL,1, "destroy-owner po=%p proc=%p (%d, %s)", 2367 po, po->po_owner, po->po_owner->p_pid, po->po_owner->p_comm); 2368 2369 mtx_destroy(&po->po_mtx); 2370 free(po, M_PMC); 2371 } 2372 2373 /* 2374 * Allocate a thread descriptor from the free pool. 2375 * 2376 * NOTE: This *can* return NULL. 2377 */ 2378 static struct pmc_thread * 2379 pmc_thread_descriptor_pool_alloc(void) 2380 { 2381 struct pmc_thread *pt; 2382 2383 mtx_lock_spin(&pmc_threadfreelist_mtx); 2384 if ((pt = LIST_FIRST(&pmc_threadfreelist)) != NULL) { 2385 LIST_REMOVE(pt, pt_next); 2386 pmc_threadfreelist_entries--; 2387 } 2388 mtx_unlock_spin(&pmc_threadfreelist_mtx); 2389 2390 return (pt); 2391 } 2392 2393 /* 2394 * Add a thread descriptor to the free pool. We use this instead of free() 2395 * to maintain a cache of free entries. Additionally, we can safely call 2396 * this function when we cannot call free(), such as in a critical section. 2397 * 2398 */ 2399 static void 2400 pmc_thread_descriptor_pool_free(struct pmc_thread *pt) 2401 { 2402 2403 if (pt == NULL) 2404 return; 2405 2406 memset(pt, 0, THREADENTRY_SIZE); 2407 mtx_lock_spin(&pmc_threadfreelist_mtx); 2408 LIST_INSERT_HEAD(&pmc_threadfreelist, pt, pt_next); 2409 pmc_threadfreelist_entries++; 2410 if (pmc_threadfreelist_entries > pmc_threadfreelist_max) 2411 GROUPTASK_ENQUEUE(&free_gtask); 2412 mtx_unlock_spin(&pmc_threadfreelist_mtx); 2413 } 2414 2415 /* 2416 * A callout to manage the free list. 2417 */ 2418 static void 2419 pmc_thread_descriptor_pool_free_task(void *arg __unused) 2420 { 2421 struct pmc_thread *pt; 2422 LIST_HEAD(, pmc_thread) tmplist; 2423 int delta; 2424 2425 LIST_INIT(&tmplist); 2426 /* Determine what changes, if any, we need to make. */ 2427 mtx_lock_spin(&pmc_threadfreelist_mtx); 2428 delta = pmc_threadfreelist_entries - pmc_threadfreelist_max; 2429 while (delta > 0 && 2430 (pt = LIST_FIRST(&pmc_threadfreelist)) != NULL) { 2431 delta--; 2432 LIST_REMOVE(pt, pt_next); 2433 LIST_INSERT_HEAD(&tmplist, pt, pt_next); 2434 } 2435 mtx_unlock_spin(&pmc_threadfreelist_mtx); 2436 2437 /* If there are entries to free, free them. */ 2438 while (!LIST_EMPTY(&tmplist)) { 2439 pt = LIST_FIRST(&tmplist); 2440 LIST_REMOVE(pt, pt_next); 2441 free(pt, M_PMC); 2442 } 2443 } 2444 2445 /* 2446 * Drain the thread free pool, freeing all allocations. 2447 */ 2448 static void 2449 pmc_thread_descriptor_pool_drain() 2450 { 2451 struct pmc_thread *pt, *next; 2452 2453 LIST_FOREACH_SAFE(pt, &pmc_threadfreelist, pt_next, next) { 2454 LIST_REMOVE(pt, pt_next); 2455 free(pt, M_PMC); 2456 } 2457 } 2458 2459 /* 2460 * find the descriptor corresponding to thread 'td', adding or removing it 2461 * as specified by 'mode'. 2462 * 2463 * Note that this supports additional mode flags in addition to those 2464 * supported by pmc_find_process_descriptor(): 2465 * PMC_FLAG_NOWAIT: Causes the function to not wait for mallocs. 2466 * This makes it safe to call while holding certain other locks. 2467 */ 2468 2469 static struct pmc_thread * 2470 pmc_find_thread_descriptor(struct pmc_process *pp, struct thread *td, 2471 uint32_t mode) 2472 { 2473 struct pmc_thread *pt = NULL, *ptnew = NULL; 2474 int wait_flag; 2475 2476 KASSERT(td != NULL, ("[pmc,%d] called to add NULL td", __LINE__)); 2477 2478 /* 2479 * Pre-allocate memory in the PMC_FLAG_ALLOCATE case prior to 2480 * acquiring the lock. 2481 */ 2482 if (mode & PMC_FLAG_ALLOCATE) { 2483 if ((ptnew = pmc_thread_descriptor_pool_alloc()) == NULL) { 2484 wait_flag = M_WAITOK; 2485 if ((mode & PMC_FLAG_NOWAIT) || in_epoch(global_epoch_preempt)) 2486 wait_flag = M_NOWAIT; 2487 2488 ptnew = malloc(THREADENTRY_SIZE, M_PMC, 2489 wait_flag|M_ZERO); 2490 } 2491 } 2492 2493 mtx_lock_spin(pp->pp_tdslock); 2494 2495 LIST_FOREACH(pt, &pp->pp_tds, pt_next) 2496 if (pt->pt_td == td) 2497 break; 2498 2499 if ((mode & PMC_FLAG_REMOVE) && pt != NULL) 2500 LIST_REMOVE(pt, pt_next); 2501 2502 if ((mode & PMC_FLAG_ALLOCATE) && pt == NULL && ptnew != NULL) { 2503 pt = ptnew; 2504 ptnew = NULL; 2505 pt->pt_td = td; 2506 LIST_INSERT_HEAD(&pp->pp_tds, pt, pt_next); 2507 } 2508 2509 mtx_unlock_spin(pp->pp_tdslock); 2510 2511 if (ptnew != NULL) { 2512 free(ptnew, M_PMC); 2513 } 2514 2515 return pt; 2516 } 2517 2518 /* 2519 * Try to add thread descriptors for each thread in a process. 2520 */ 2521 2522 static void 2523 pmc_add_thread_descriptors_from_proc(struct proc *p, struct pmc_process *pp) 2524 { 2525 struct thread *curtd; 2526 struct pmc_thread **tdlist; 2527 int i, tdcnt, tdlistsz; 2528 2529 KASSERT(!PROC_LOCKED(p), ("[pmc,%d] proc unexpectedly locked", 2530 __LINE__)); 2531 tdcnt = 32; 2532 restart: 2533 tdlistsz = roundup2(tdcnt, 32); 2534 2535 tdcnt = 0; 2536 tdlist = malloc(sizeof(struct pmc_thread*) * tdlistsz, M_TEMP, M_WAITOK); 2537 2538 PROC_LOCK(p); 2539 FOREACH_THREAD_IN_PROC(p, curtd) 2540 tdcnt++; 2541 if (tdcnt >= tdlistsz) { 2542 PROC_UNLOCK(p); 2543 free(tdlist, M_TEMP); 2544 goto restart; 2545 } 2546 /* 2547 * Try to add each thread to the list without sleeping. If unable, 2548 * add to a queue to retry after dropping the process lock. 2549 */ 2550 tdcnt = 0; 2551 FOREACH_THREAD_IN_PROC(p, curtd) { 2552 tdlist[tdcnt] = pmc_find_thread_descriptor(pp, curtd, 2553 PMC_FLAG_ALLOCATE|PMC_FLAG_NOWAIT); 2554 if (tdlist[tdcnt] == NULL) { 2555 PROC_UNLOCK(p); 2556 for (i = 0; i <= tdcnt; i++) 2557 pmc_thread_descriptor_pool_free(tdlist[i]); 2558 free(tdlist, M_TEMP); 2559 goto restart; 2560 } 2561 tdcnt++; 2562 } 2563 PROC_UNLOCK(p); 2564 free(tdlist, M_TEMP); 2565 } 2566 2567 /* 2568 * find the descriptor corresponding to process 'p', adding or removing it 2569 * as specified by 'mode'. 2570 */ 2571 2572 static struct pmc_process * 2573 pmc_find_process_descriptor(struct proc *p, uint32_t mode) 2574 { 2575 uint32_t hindex; 2576 struct pmc_process *pp, *ppnew; 2577 struct pmc_processhash *pph; 2578 2579 hindex = PMC_HASH_PTR(p, pmc_processhashmask); 2580 pph = &pmc_processhash[hindex]; 2581 2582 ppnew = NULL; 2583 2584 /* 2585 * Pre-allocate memory in the PMC_FLAG_ALLOCATE case since we 2586 * cannot call malloc(9) once we hold a spin lock. 2587 */ 2588 if (mode & PMC_FLAG_ALLOCATE) 2589 ppnew = malloc(sizeof(struct pmc_process) + md->pmd_npmc * 2590 sizeof(struct pmc_targetstate), M_PMC, M_WAITOK|M_ZERO); 2591 2592 mtx_lock_spin(&pmc_processhash_mtx); 2593 LIST_FOREACH(pp, pph, pp_next) 2594 if (pp->pp_proc == p) 2595 break; 2596 2597 if ((mode & PMC_FLAG_REMOVE) && pp != NULL) 2598 LIST_REMOVE(pp, pp_next); 2599 2600 if ((mode & PMC_FLAG_ALLOCATE) && pp == NULL && 2601 ppnew != NULL) { 2602 ppnew->pp_proc = p; 2603 LIST_INIT(&ppnew->pp_tds); 2604 ppnew->pp_tdslock = mtx_pool_find(pmc_mtxpool, ppnew); 2605 LIST_INSERT_HEAD(pph, ppnew, pp_next); 2606 mtx_unlock_spin(&pmc_processhash_mtx); 2607 pp = ppnew; 2608 ppnew = NULL; 2609 2610 /* Add thread descriptors for this process' current threads. */ 2611 pmc_add_thread_descriptors_from_proc(p, pp); 2612 } 2613 else 2614 mtx_unlock_spin(&pmc_processhash_mtx); 2615 2616 if (ppnew != NULL) 2617 free(ppnew, M_PMC); 2618 2619 return pp; 2620 } 2621 2622 /* 2623 * remove a process descriptor from the process hash table. 2624 */ 2625 2626 static void 2627 pmc_remove_process_descriptor(struct pmc_process *pp) 2628 { 2629 KASSERT(pp->pp_refcnt == 0, 2630 ("[pmc,%d] Removing process descriptor %p with count %d", 2631 __LINE__, pp, pp->pp_refcnt)); 2632 2633 mtx_lock_spin(&pmc_processhash_mtx); 2634 LIST_REMOVE(pp, pp_next); 2635 mtx_unlock_spin(&pmc_processhash_mtx); 2636 } 2637 2638 /* 2639 * destroy a process descriptor. 2640 */ 2641 2642 static void 2643 pmc_destroy_process_descriptor(struct pmc_process *pp) 2644 { 2645 struct pmc_thread *pmc_td; 2646 2647 while ((pmc_td = LIST_FIRST(&pp->pp_tds)) != NULL) { 2648 LIST_REMOVE(pmc_td, pt_next); 2649 pmc_thread_descriptor_pool_free(pmc_td); 2650 } 2651 free(pp, M_PMC); 2652 } 2653 2654 2655 /* 2656 * find an owner descriptor corresponding to proc 'p' 2657 */ 2658 2659 static struct pmc_owner * 2660 pmc_find_owner_descriptor(struct proc *p) 2661 { 2662 uint32_t hindex; 2663 struct pmc_owner *po; 2664 struct pmc_ownerhash *poh; 2665 2666 hindex = PMC_HASH_PTR(p, pmc_ownerhashmask); 2667 poh = &pmc_ownerhash[hindex]; 2668 2669 po = NULL; 2670 LIST_FOREACH(po, poh, po_next) 2671 if (po->po_owner == p) 2672 break; 2673 2674 PMCDBG5(OWN,FND,1, "find-owner proc=%p (%d, %s) hindex=0x%x -> " 2675 "pmc-owner=%p", p, p->p_pid, p->p_comm, hindex, po); 2676 2677 return po; 2678 } 2679 2680 /* 2681 * pmc_allocate_pmc_descriptor 2682 * 2683 * Allocate a pmc descriptor and initialize its 2684 * fields. 2685 */ 2686 2687 static struct pmc * 2688 pmc_allocate_pmc_descriptor(void) 2689 { 2690 struct pmc *pmc; 2691 2692 pmc = malloc(sizeof(struct pmc), M_PMC, M_WAITOK|M_ZERO); 2693 pmc->pm_runcount = counter_u64_alloc(M_WAITOK); 2694 pmc->pm_pcpu_state = malloc(sizeof(struct pmc_pcpu_state)*mp_ncpus, M_PMC, M_WAITOK|M_ZERO); 2695 PMCDBG1(PMC,ALL,1, "allocate-pmc -> pmc=%p", pmc); 2696 2697 return pmc; 2698 } 2699 2700 /* 2701 * Destroy a pmc descriptor. 2702 */ 2703 2704 static void 2705 pmc_destroy_pmc_descriptor(struct pmc *pm) 2706 { 2707 2708 KASSERT(pm->pm_state == PMC_STATE_DELETED || 2709 pm->pm_state == PMC_STATE_FREE, 2710 ("[pmc,%d] destroying non-deleted PMC", __LINE__)); 2711 KASSERT(LIST_EMPTY(&pm->pm_targets), 2712 ("[pmc,%d] destroying pmc with targets", __LINE__)); 2713 KASSERT(pm->pm_owner == NULL, 2714 ("[pmc,%d] destroying pmc attached to an owner", __LINE__)); 2715 KASSERT(counter_u64_fetch(pm->pm_runcount) == 0, 2716 ("[pmc,%d] pmc has non-zero run count %ld", __LINE__, 2717 (unsigned long)counter_u64_fetch(pm->pm_runcount))); 2718 2719 counter_u64_free(pm->pm_runcount); 2720 free(pm->pm_pcpu_state, M_PMC); 2721 free(pm, M_PMC); 2722 } 2723 2724 static void 2725 pmc_wait_for_pmc_idle(struct pmc *pm) 2726 { 2727 #ifdef HWPMC_DEBUG 2728 volatile int maxloop; 2729 2730 maxloop = 100 * pmc_cpu_max(); 2731 #endif 2732 /* 2733 * Loop (with a forced context switch) till the PMC's runcount 2734 * comes down to zero. 2735 */ 2736 pmclog_flush(pm->pm_owner, 1); 2737 while (counter_u64_fetch(pm->pm_runcount) > 0) { 2738 pmclog_flush(pm->pm_owner, 1); 2739 #ifdef HWPMC_DEBUG 2740 maxloop--; 2741 KASSERT(maxloop > 0, 2742 ("[pmc,%d] (ri%d, rc%ld) waiting too long for " 2743 "pmc to be free", __LINE__, 2744 PMC_TO_ROWINDEX(pm), (unsigned long)counter_u64_fetch(pm->pm_runcount))); 2745 #endif 2746 pmc_force_context_switch(); 2747 } 2748 } 2749 2750 /* 2751 * This function does the following things: 2752 * 2753 * - detaches the PMC from hardware 2754 * - unlinks all target threads that were attached to it 2755 * - removes the PMC from its owner's list 2756 * - destroys the PMC private mutex 2757 * 2758 * Once this function completes, the given pmc pointer can be freed by 2759 * calling pmc_destroy_pmc_descriptor(). 2760 */ 2761 2762 static void 2763 pmc_release_pmc_descriptor(struct pmc *pm) 2764 { 2765 enum pmc_mode mode; 2766 struct pmc_hw *phw; 2767 u_int adjri, ri, cpu; 2768 struct pmc_owner *po; 2769 struct pmc_binding pb; 2770 struct pmc_process *pp; 2771 struct pmc_classdep *pcd; 2772 struct pmc_target *ptgt, *tmp; 2773 2774 sx_assert(&pmc_sx, SX_XLOCKED); 2775 2776 KASSERT(pm, ("[pmc,%d] null pmc", __LINE__)); 2777 2778 ri = PMC_TO_ROWINDEX(pm); 2779 pcd = pmc_ri_to_classdep(md, ri, &adjri); 2780 mode = PMC_TO_MODE(pm); 2781 2782 PMCDBG3(PMC,REL,1, "release-pmc pmc=%p ri=%d mode=%d", pm, ri, 2783 mode); 2784 2785 /* 2786 * First, we take the PMC off hardware. 2787 */ 2788 cpu = 0; 2789 if (PMC_IS_SYSTEM_MODE(mode)) { 2790 2791 /* 2792 * A system mode PMC runs on a specific CPU. Switch 2793 * to this CPU and turn hardware off. 2794 */ 2795 pmc_save_cpu_binding(&pb); 2796 2797 cpu = PMC_TO_CPU(pm); 2798 2799 pmc_select_cpu(cpu); 2800 2801 /* switch off non-stalled CPUs */ 2802 pm->pm_pcpu_state[cpu].pps_cpustate = 0; 2803 if (pm->pm_state == PMC_STATE_RUNNING && 2804 pm->pm_pcpu_state[cpu].pps_stalled == 0) { 2805 2806 phw = pmc_pcpu[cpu]->pc_hwpmcs[ri]; 2807 2808 KASSERT(phw->phw_pmc == pm, 2809 ("[pmc, %d] pmc ptr ri(%d) hw(%p) pm(%p)", 2810 __LINE__, ri, phw->phw_pmc, pm)); 2811 PMCDBG2(PMC,REL,2, "stopping cpu=%d ri=%d", cpu, ri); 2812 2813 critical_enter(); 2814 pcd->pcd_stop_pmc(cpu, adjri); 2815 critical_exit(); 2816 } 2817 2818 PMCDBG2(PMC,REL,2, "decfg cpu=%d ri=%d", cpu, ri); 2819 2820 critical_enter(); 2821 pcd->pcd_config_pmc(cpu, adjri, NULL); 2822 critical_exit(); 2823 2824 /* adjust the global and process count of SS mode PMCs */ 2825 if (mode == PMC_MODE_SS && pm->pm_state == PMC_STATE_RUNNING) { 2826 po = pm->pm_owner; 2827 po->po_sscount--; 2828 if (po->po_sscount == 0) { 2829 atomic_subtract_rel_int(&pmc_ss_count, 1); 2830 CK_LIST_REMOVE(po, po_ssnext); 2831 epoch_wait_preempt(global_epoch_preempt); 2832 } 2833 } 2834 2835 pm->pm_state = PMC_STATE_DELETED; 2836 2837 pmc_restore_cpu_binding(&pb); 2838 2839 /* 2840 * We could have references to this PMC structure in 2841 * the per-cpu sample queues. Wait for the queue to 2842 * drain. 2843 */ 2844 pmc_wait_for_pmc_idle(pm); 2845 2846 } else if (PMC_IS_VIRTUAL_MODE(mode)) { 2847 2848 /* 2849 * A virtual PMC could be running on multiple CPUs at 2850 * a given instant. 2851 * 2852 * By marking its state as DELETED, we ensure that 2853 * this PMC is never further scheduled on hardware. 2854 * 2855 * Then we wait till all CPUs are done with this PMC. 2856 */ 2857 pm->pm_state = PMC_STATE_DELETED; 2858 2859 2860 /* Wait for the PMCs runcount to come to zero. */ 2861 pmc_wait_for_pmc_idle(pm); 2862 2863 /* 2864 * At this point the PMC is off all CPUs and cannot be 2865 * freshly scheduled onto a CPU. It is now safe to 2866 * unlink all targets from this PMC. If a 2867 * process-record's refcount falls to zero, we remove 2868 * it from the hash table. The module-wide SX lock 2869 * protects us from races. 2870 */ 2871 LIST_FOREACH_SAFE(ptgt, &pm->pm_targets, pt_next, tmp) { 2872 pp = ptgt->pt_process; 2873 pmc_unlink_target_process(pm, pp); /* frees 'ptgt' */ 2874 2875 PMCDBG1(PMC,REL,3, "pp->refcnt=%d", pp->pp_refcnt); 2876 2877 /* 2878 * If the target process record shows that no 2879 * PMCs are attached to it, reclaim its space. 2880 */ 2881 2882 if (pp->pp_refcnt == 0) { 2883 pmc_remove_process_descriptor(pp); 2884 pmc_destroy_process_descriptor(pp); 2885 } 2886 } 2887 2888 cpu = curthread->td_oncpu; /* setup cpu for pmd_release() */ 2889 2890 } 2891 2892 /* 2893 * Release any MD resources 2894 */ 2895 (void) pcd->pcd_release_pmc(cpu, adjri, pm); 2896 2897 /* 2898 * Update row disposition 2899 */ 2900 2901 if (PMC_IS_SYSTEM_MODE(PMC_TO_MODE(pm))) 2902 PMC_UNMARK_ROW_STANDALONE(ri); 2903 else 2904 PMC_UNMARK_ROW_THREAD(ri); 2905 2906 /* unlink from the owner's list */ 2907 if (pm->pm_owner) { 2908 LIST_REMOVE(pm, pm_next); 2909 pm->pm_owner = NULL; 2910 } 2911 } 2912 2913 /* 2914 * Register an owner and a pmc. 2915 */ 2916 2917 static int 2918 pmc_register_owner(struct proc *p, struct pmc *pmc) 2919 { 2920 struct pmc_owner *po; 2921 2922 sx_assert(&pmc_sx, SX_XLOCKED); 2923 2924 if ((po = pmc_find_owner_descriptor(p)) == NULL) 2925 if ((po = pmc_allocate_owner_descriptor(p)) == NULL) 2926 return ENOMEM; 2927 2928 KASSERT(pmc->pm_owner == NULL, 2929 ("[pmc,%d] attempting to own an initialized PMC", __LINE__)); 2930 pmc->pm_owner = po; 2931 2932 LIST_INSERT_HEAD(&po->po_pmcs, pmc, pm_next); 2933 2934 PROC_LOCK(p); 2935 p->p_flag |= P_HWPMC; 2936 PROC_UNLOCK(p); 2937 2938 if (po->po_flags & PMC_PO_OWNS_LOGFILE) 2939 pmclog_process_pmcallocate(pmc); 2940 2941 PMCDBG2(PMC,REG,1, "register-owner pmc-owner=%p pmc=%p", 2942 po, pmc); 2943 2944 return 0; 2945 } 2946 2947 /* 2948 * Return the current row disposition: 2949 * == 0 => FREE 2950 * > 0 => PROCESS MODE 2951 * < 0 => SYSTEM MODE 2952 */ 2953 2954 int 2955 pmc_getrowdisp(int ri) 2956 { 2957 return pmc_pmcdisp[ri]; 2958 } 2959 2960 /* 2961 * Check if a PMC at row index 'ri' can be allocated to the current 2962 * process. 2963 * 2964 * Allocation can fail if: 2965 * - the current process is already being profiled by a PMC at index 'ri', 2966 * attached to it via OP_PMCATTACH. 2967 * - the current process has already allocated a PMC at index 'ri' 2968 * via OP_ALLOCATE. 2969 */ 2970 2971 static int 2972 pmc_can_allocate_rowindex(struct proc *p, unsigned int ri, int cpu) 2973 { 2974 enum pmc_mode mode; 2975 struct pmc *pm; 2976 struct pmc_owner *po; 2977 struct pmc_process *pp; 2978 2979 PMCDBG5(PMC,ALR,1, "can-allocate-rowindex proc=%p (%d, %s) ri=%d " 2980 "cpu=%d", p, p->p_pid, p->p_comm, ri, cpu); 2981 2982 /* 2983 * We shouldn't have already allocated a process-mode PMC at 2984 * row index 'ri'. 2985 * 2986 * We shouldn't have allocated a system-wide PMC on the same 2987 * CPU and same RI. 2988 */ 2989 if ((po = pmc_find_owner_descriptor(p)) != NULL) 2990 LIST_FOREACH(pm, &po->po_pmcs, pm_next) { 2991 if (PMC_TO_ROWINDEX(pm) == ri) { 2992 mode = PMC_TO_MODE(pm); 2993 if (PMC_IS_VIRTUAL_MODE(mode)) 2994 return EEXIST; 2995 if (PMC_IS_SYSTEM_MODE(mode) && 2996 (int) PMC_TO_CPU(pm) == cpu) 2997 return EEXIST; 2998 } 2999 } 3000 3001 /* 3002 * We also shouldn't be the target of any PMC at this index 3003 * since otherwise a PMC_ATTACH to ourselves will fail. 3004 */ 3005 if ((pp = pmc_find_process_descriptor(p, 0)) != NULL) 3006 if (pp->pp_pmcs[ri].pp_pmc) 3007 return EEXIST; 3008 3009 PMCDBG4(PMC,ALR,2, "can-allocate-rowindex proc=%p (%d, %s) ri=%d ok", 3010 p, p->p_pid, p->p_comm, ri); 3011 3012 return 0; 3013 } 3014 3015 /* 3016 * Check if a given PMC at row index 'ri' can be currently used in 3017 * mode 'mode'. 3018 */ 3019 3020 static int 3021 pmc_can_allocate_row(int ri, enum pmc_mode mode) 3022 { 3023 enum pmc_disp disp; 3024 3025 sx_assert(&pmc_sx, SX_XLOCKED); 3026 3027 PMCDBG2(PMC,ALR,1, "can-allocate-row ri=%d mode=%d", ri, mode); 3028 3029 if (PMC_IS_SYSTEM_MODE(mode)) 3030 disp = PMC_DISP_STANDALONE; 3031 else 3032 disp = PMC_DISP_THREAD; 3033 3034 /* 3035 * check disposition for PMC row 'ri': 3036 * 3037 * Expected disposition Row-disposition Result 3038 * 3039 * STANDALONE STANDALONE or FREE proceed 3040 * STANDALONE THREAD fail 3041 * THREAD THREAD or FREE proceed 3042 * THREAD STANDALONE fail 3043 */ 3044 3045 if (!PMC_ROW_DISP_IS_FREE(ri) && 3046 !(disp == PMC_DISP_THREAD && PMC_ROW_DISP_IS_THREAD(ri)) && 3047 !(disp == PMC_DISP_STANDALONE && PMC_ROW_DISP_IS_STANDALONE(ri))) 3048 return EBUSY; 3049 3050 /* 3051 * All OK 3052 */ 3053 3054 PMCDBG2(PMC,ALR,2, "can-allocate-row ri=%d mode=%d ok", ri, mode); 3055 3056 return 0; 3057 3058 } 3059 3060 /* 3061 * Find a PMC descriptor with user handle 'pmcid' for thread 'td'. 3062 */ 3063 3064 static struct pmc * 3065 pmc_find_pmc_descriptor_in_process(struct pmc_owner *po, pmc_id_t pmcid) 3066 { 3067 struct pmc *pm; 3068 3069 KASSERT(PMC_ID_TO_ROWINDEX(pmcid) < md->pmd_npmc, 3070 ("[pmc,%d] Illegal pmc index %d (max %d)", __LINE__, 3071 PMC_ID_TO_ROWINDEX(pmcid), md->pmd_npmc)); 3072 3073 LIST_FOREACH(pm, &po->po_pmcs, pm_next) 3074 if (pm->pm_id == pmcid) 3075 return pm; 3076 3077 return NULL; 3078 } 3079 3080 static int 3081 pmc_find_pmc(pmc_id_t pmcid, struct pmc **pmc) 3082 { 3083 3084 struct pmc *pm, *opm; 3085 struct pmc_owner *po; 3086 struct pmc_process *pp; 3087 3088 PMCDBG1(PMC,FND,1, "find-pmc id=%d", pmcid); 3089 if (PMC_ID_TO_ROWINDEX(pmcid) >= md->pmd_npmc) 3090 return (EINVAL); 3091 3092 if ((po = pmc_find_owner_descriptor(curthread->td_proc)) == NULL) { 3093 /* 3094 * In case of PMC_F_DESCENDANTS child processes we will not find 3095 * the current process in the owners hash list. Find the owner 3096 * process first and from there lookup the po. 3097 */ 3098 if ((pp = pmc_find_process_descriptor(curthread->td_proc, 3099 PMC_FLAG_NONE)) == NULL) { 3100 return ESRCH; 3101 } else { 3102 opm = pp->pp_pmcs[PMC_ID_TO_ROWINDEX(pmcid)].pp_pmc; 3103 if (opm == NULL) 3104 return ESRCH; 3105 if ((opm->pm_flags & (PMC_F_ATTACHED_TO_OWNER| 3106 PMC_F_DESCENDANTS)) != (PMC_F_ATTACHED_TO_OWNER| 3107 PMC_F_DESCENDANTS)) 3108 return ESRCH; 3109 po = opm->pm_owner; 3110 } 3111 } 3112 3113 if ((pm = pmc_find_pmc_descriptor_in_process(po, pmcid)) == NULL) 3114 return EINVAL; 3115 3116 PMCDBG2(PMC,FND,2, "find-pmc id=%d -> pmc=%p", pmcid, pm); 3117 3118 *pmc = pm; 3119 return 0; 3120 } 3121 3122 /* 3123 * Start a PMC. 3124 */ 3125 3126 static int 3127 pmc_start(struct pmc *pm) 3128 { 3129 enum pmc_mode mode; 3130 struct pmc_owner *po; 3131 struct pmc_binding pb; 3132 struct pmc_classdep *pcd; 3133 int adjri, error, cpu, ri; 3134 3135 KASSERT(pm != NULL, 3136 ("[pmc,%d] null pm", __LINE__)); 3137 3138 mode = PMC_TO_MODE(pm); 3139 ri = PMC_TO_ROWINDEX(pm); 3140 pcd = pmc_ri_to_classdep(md, ri, &adjri); 3141 3142 error = 0; 3143 3144 PMCDBG3(PMC,OPS,1, "start pmc=%p mode=%d ri=%d", pm, mode, ri); 3145 3146 po = pm->pm_owner; 3147 3148 /* 3149 * Disallow PMCSTART if a logfile is required but has not been 3150 * configured yet. 3151 */ 3152 if ((pm->pm_flags & PMC_F_NEEDS_LOGFILE) && 3153 (po->po_flags & PMC_PO_OWNS_LOGFILE) == 0) 3154 return (EDOOFUS); /* programming error */ 3155 3156 /* 3157 * If this is a sampling mode PMC, log mapping information for 3158 * the kernel modules that are currently loaded. 3159 */ 3160 if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm))) 3161 pmc_log_kernel_mappings(pm); 3162 3163 if (PMC_IS_VIRTUAL_MODE(mode)) { 3164 3165 /* 3166 * If a PMCATTACH has never been done on this PMC, 3167 * attach it to its owner process. 3168 */ 3169 3170 if (LIST_EMPTY(&pm->pm_targets)) 3171 error = (pm->pm_flags & PMC_F_ATTACH_DONE) ? ESRCH : 3172 pmc_attach_process(po->po_owner, pm); 3173 3174 /* 3175 * If the PMC is attached to its owner, then force a context 3176 * switch to ensure that the MD state gets set correctly. 3177 */ 3178 3179 if (error == 0) { 3180 pm->pm_state = PMC_STATE_RUNNING; 3181 if (pm->pm_flags & PMC_F_ATTACHED_TO_OWNER) 3182 pmc_force_context_switch(); 3183 } 3184 3185 return (error); 3186 } 3187 3188 3189 /* 3190 * A system-wide PMC. 3191 * 3192 * Add the owner to the global list if this is a system-wide 3193 * sampling PMC. 3194 */ 3195 3196 if (mode == PMC_MODE_SS) { 3197 /* 3198 * Log mapping information for all existing processes in the 3199 * system. Subsequent mappings are logged as they happen; 3200 * see pmc_process_mmap(). 3201 */ 3202 if (po->po_logprocmaps == 0) { 3203 pmc_log_all_process_mappings(po); 3204 po->po_logprocmaps = 1; 3205 } 3206 po->po_sscount++; 3207 if (po->po_sscount == 1) { 3208 atomic_add_rel_int(&pmc_ss_count, 1); 3209 CK_LIST_INSERT_HEAD(&pmc_ss_owners, po, po_ssnext); 3210 PMCDBG1(PMC,OPS,1, "po=%p in global list", po); 3211 } 3212 } 3213 3214 /* 3215 * Move to the CPU associated with this 3216 * PMC, and start the hardware. 3217 */ 3218 3219 pmc_save_cpu_binding(&pb); 3220 3221 cpu = PMC_TO_CPU(pm); 3222 3223 if (!pmc_cpu_is_active(cpu)) 3224 return (ENXIO); 3225 3226 pmc_select_cpu(cpu); 3227 3228 /* 3229 * global PMCs are configured at allocation time 3230 * so write out the initial value and start the PMC. 3231 */ 3232 3233 pm->pm_state = PMC_STATE_RUNNING; 3234 3235 critical_enter(); 3236 if ((error = pcd->pcd_write_pmc(cpu, adjri, 3237 PMC_IS_SAMPLING_MODE(mode) ? 3238 pm->pm_sc.pm_reloadcount : 3239 pm->pm_sc.pm_initial)) == 0) { 3240 /* If a sampling mode PMC, reset stalled state. */ 3241 if (PMC_IS_SAMPLING_MODE(mode)) 3242 pm->pm_pcpu_state[cpu].pps_stalled = 0; 3243 3244 /* Indicate that we desire this to run. Start it. */ 3245 pm->pm_pcpu_state[cpu].pps_cpustate = 1; 3246 error = pcd->pcd_start_pmc(cpu, adjri); 3247 } 3248 critical_exit(); 3249 3250 pmc_restore_cpu_binding(&pb); 3251 3252 return (error); 3253 } 3254 3255 /* 3256 * Stop a PMC. 3257 */ 3258 3259 static int 3260 pmc_stop(struct pmc *pm) 3261 { 3262 struct pmc_owner *po; 3263 struct pmc_binding pb; 3264 struct pmc_classdep *pcd; 3265 int adjri, cpu, error, ri; 3266 3267 KASSERT(pm != NULL, ("[pmc,%d] null pmc", __LINE__)); 3268 3269 PMCDBG3(PMC,OPS,1, "stop pmc=%p mode=%d ri=%d", pm, 3270 PMC_TO_MODE(pm), PMC_TO_ROWINDEX(pm)); 3271 3272 pm->pm_state = PMC_STATE_STOPPED; 3273 3274 /* 3275 * If the PMC is a virtual mode one, changing the state to 3276 * non-RUNNING is enough to ensure that the PMC never gets 3277 * scheduled. 3278 * 3279 * If this PMC is current running on a CPU, then it will 3280 * handled correctly at the time its target process is context 3281 * switched out. 3282 */ 3283 3284 if (PMC_IS_VIRTUAL_MODE(PMC_TO_MODE(pm))) 3285 return 0; 3286 3287 /* 3288 * A system-mode PMC. Move to the CPU associated with 3289 * this PMC, and stop the hardware. We update the 3290 * 'initial count' so that a subsequent PMCSTART will 3291 * resume counting from the current hardware count. 3292 */ 3293 3294 pmc_save_cpu_binding(&pb); 3295 3296 cpu = PMC_TO_CPU(pm); 3297 3298 KASSERT(cpu >= 0 && cpu < pmc_cpu_max(), 3299 ("[pmc,%d] illegal cpu=%d", __LINE__, cpu)); 3300 3301 if (!pmc_cpu_is_active(cpu)) 3302 return ENXIO; 3303 3304 pmc_select_cpu(cpu); 3305 3306 ri = PMC_TO_ROWINDEX(pm); 3307 pcd = pmc_ri_to_classdep(md, ri, &adjri); 3308 3309 pm->pm_pcpu_state[cpu].pps_cpustate = 0; 3310 critical_enter(); 3311 if ((error = pcd->pcd_stop_pmc(cpu, adjri)) == 0) 3312 error = pcd->pcd_read_pmc(cpu, adjri, &pm->pm_sc.pm_initial); 3313 critical_exit(); 3314 3315 pmc_restore_cpu_binding(&pb); 3316 3317 po = pm->pm_owner; 3318 3319 /* remove this owner from the global list of SS PMC owners */ 3320 if (PMC_TO_MODE(pm) == PMC_MODE_SS) { 3321 po->po_sscount--; 3322 if (po->po_sscount == 0) { 3323 atomic_subtract_rel_int(&pmc_ss_count, 1); 3324 CK_LIST_REMOVE(po, po_ssnext); 3325 epoch_wait_preempt(global_epoch_preempt); 3326 PMCDBG1(PMC,OPS,2,"po=%p removed from global list", po); 3327 } 3328 } 3329 3330 return (error); 3331 } 3332 3333 static struct pmc_classdep * 3334 pmc_class_to_classdep(enum pmc_class class) 3335 { 3336 int n; 3337 3338 for (n = 0; n < md->pmd_nclass; n++) 3339 if (md->pmd_classdep[n].pcd_class == class) 3340 return (&md->pmd_classdep[n]); 3341 return (NULL); 3342 } 3343 3344 #if defined(HWPMC_DEBUG) && defined(KTR) 3345 static const char *pmc_op_to_name[] = { 3346 #undef __PMC_OP 3347 #define __PMC_OP(N, D) #N , 3348 __PMC_OPS() 3349 NULL 3350 }; 3351 #endif 3352 3353 /* 3354 * The syscall interface 3355 */ 3356 3357 #define PMC_GET_SX_XLOCK(...) do { \ 3358 sx_xlock(&pmc_sx); \ 3359 if (pmc_hook == NULL) { \ 3360 sx_xunlock(&pmc_sx); \ 3361 return __VA_ARGS__; \ 3362 } \ 3363 } while (0) 3364 3365 #define PMC_DOWNGRADE_SX() do { \ 3366 sx_downgrade(&pmc_sx); \ 3367 is_sx_downgraded = 1; \ 3368 } while (0) 3369 3370 static int 3371 pmc_syscall_handler(struct thread *td, void *syscall_args) 3372 { 3373 int error, is_sx_downgraded, op; 3374 struct pmc_syscall_args *c; 3375 void *pmclog_proc_handle; 3376 void *arg; 3377 3378 c = (struct pmc_syscall_args *)syscall_args; 3379 op = c->pmop_code; 3380 arg = c->pmop_data; 3381 /* PMC isn't set up yet */ 3382 if (pmc_hook == NULL) 3383 return (EINVAL); 3384 if (op == PMC_OP_CONFIGURELOG) { 3385 /* 3386 * We cannot create the logging process inside 3387 * pmclog_configure_log() because there is a LOR 3388 * between pmc_sx and process structure locks. 3389 * Instead, pre-create the process and ignite the loop 3390 * if everything is fine, otherwise direct the process 3391 * to exit. 3392 */ 3393 error = pmclog_proc_create(td, &pmclog_proc_handle); 3394 if (error != 0) 3395 goto done_syscall; 3396 } 3397 3398 PMC_GET_SX_XLOCK(ENOSYS); 3399 is_sx_downgraded = 0; 3400 PMCDBG3(MOD,PMS,1, "syscall op=%d \"%s\" arg=%p", op, 3401 pmc_op_to_name[op], arg); 3402 3403 error = 0; 3404 counter_u64_add(pmc_stats.pm_syscalls, 1); 3405 3406 switch (op) { 3407 3408 3409 /* 3410 * Configure a log file. 3411 * 3412 * XXX This OP will be reworked. 3413 */ 3414 3415 case PMC_OP_CONFIGURELOG: 3416 { 3417 struct proc *p; 3418 struct pmc *pm; 3419 struct pmc_owner *po; 3420 struct pmc_op_configurelog cl; 3421 3422 if ((error = copyin(arg, &cl, sizeof(cl))) != 0) { 3423 pmclog_proc_ignite(pmclog_proc_handle, NULL); 3424 break; 3425 } 3426 3427 /* mark this process as owning a log file */ 3428 p = td->td_proc; 3429 if ((po = pmc_find_owner_descriptor(p)) == NULL) 3430 if ((po = pmc_allocate_owner_descriptor(p)) == NULL) { 3431 pmclog_proc_ignite(pmclog_proc_handle, NULL); 3432 error = ENOMEM; 3433 break; 3434 } 3435 3436 /* 3437 * If a valid fd was passed in, try to configure that, 3438 * otherwise if 'fd' was less than zero and there was 3439 * a log file configured, flush its buffers and 3440 * de-configure it. 3441 */ 3442 if (cl.pm_logfd >= 0) { 3443 error = pmclog_configure_log(md, po, cl.pm_logfd); 3444 pmclog_proc_ignite(pmclog_proc_handle, error == 0 ? 3445 po : NULL); 3446 } else if (po->po_flags & PMC_PO_OWNS_LOGFILE) { 3447 pmclog_proc_ignite(pmclog_proc_handle, NULL); 3448 error = pmclog_close(po); 3449 if (error == 0) { 3450 LIST_FOREACH(pm, &po->po_pmcs, pm_next) 3451 if (pm->pm_flags & PMC_F_NEEDS_LOGFILE && 3452 pm->pm_state == PMC_STATE_RUNNING) 3453 pmc_stop(pm); 3454 error = pmclog_deconfigure_log(po); 3455 } 3456 } else { 3457 pmclog_proc_ignite(pmclog_proc_handle, NULL); 3458 error = EINVAL; 3459 } 3460 } 3461 break; 3462 3463 /* 3464 * Flush a log file. 3465 */ 3466 3467 case PMC_OP_FLUSHLOG: 3468 { 3469 struct pmc_owner *po; 3470 3471 sx_assert(&pmc_sx, SX_XLOCKED); 3472 3473 if ((po = pmc_find_owner_descriptor(td->td_proc)) == NULL) { 3474 error = EINVAL; 3475 break; 3476 } 3477 3478 error = pmclog_flush(po, 0); 3479 } 3480 break; 3481 3482 /* 3483 * Close a log file. 3484 */ 3485 3486 case PMC_OP_CLOSELOG: 3487 { 3488 struct pmc_owner *po; 3489 3490 sx_assert(&pmc_sx, SX_XLOCKED); 3491 3492 if ((po = pmc_find_owner_descriptor(td->td_proc)) == NULL) { 3493 error = EINVAL; 3494 break; 3495 } 3496 3497 error = pmclog_close(po); 3498 } 3499 break; 3500 3501 /* 3502 * Retrieve hardware configuration. 3503 */ 3504 3505 case PMC_OP_GETCPUINFO: /* CPU information */ 3506 { 3507 struct pmc_op_getcpuinfo gci; 3508 struct pmc_classinfo *pci; 3509 struct pmc_classdep *pcd; 3510 int cl; 3511 3512 gci.pm_cputype = md->pmd_cputype; 3513 gci.pm_ncpu = pmc_cpu_max(); 3514 gci.pm_npmc = md->pmd_npmc; 3515 gci.pm_nclass = md->pmd_nclass; 3516 pci = gci.pm_classes; 3517 pcd = md->pmd_classdep; 3518 for (cl = 0; cl < md->pmd_nclass; cl++, pci++, pcd++) { 3519 pci->pm_caps = pcd->pcd_caps; 3520 pci->pm_class = pcd->pcd_class; 3521 pci->pm_width = pcd->pcd_width; 3522 pci->pm_num = pcd->pcd_num; 3523 } 3524 error = copyout(&gci, arg, sizeof(gci)); 3525 } 3526 break; 3527 3528 /* 3529 * Retrieve soft events list. 3530 */ 3531 case PMC_OP_GETDYNEVENTINFO: 3532 { 3533 enum pmc_class cl; 3534 enum pmc_event ev; 3535 struct pmc_op_getdyneventinfo *gei; 3536 struct pmc_dyn_event_descr dev; 3537 struct pmc_soft *ps; 3538 uint32_t nevent; 3539 3540 sx_assert(&pmc_sx, SX_LOCKED); 3541 3542 gei = (struct pmc_op_getdyneventinfo *) arg; 3543 3544 if ((error = copyin(&gei->pm_class, &cl, sizeof(cl))) != 0) 3545 break; 3546 3547 /* Only SOFT class is dynamic. */ 3548 if (cl != PMC_CLASS_SOFT) { 3549 error = EINVAL; 3550 break; 3551 } 3552 3553 nevent = 0; 3554 for (ev = PMC_EV_SOFT_FIRST; (int)ev <= PMC_EV_SOFT_LAST; ev++) { 3555 ps = pmc_soft_ev_acquire(ev); 3556 if (ps == NULL) 3557 continue; 3558 bcopy(&ps->ps_ev, &dev, sizeof(dev)); 3559 pmc_soft_ev_release(ps); 3560 3561 error = copyout(&dev, 3562 &gei->pm_events[nevent], 3563 sizeof(struct pmc_dyn_event_descr)); 3564 if (error != 0) 3565 break; 3566 nevent++; 3567 } 3568 if (error != 0) 3569 break; 3570 3571 error = copyout(&nevent, &gei->pm_nevent, 3572 sizeof(nevent)); 3573 } 3574 break; 3575 3576 /* 3577 * Get module statistics 3578 */ 3579 3580 case PMC_OP_GETDRIVERSTATS: 3581 { 3582 struct pmc_op_getdriverstats gms; 3583 #define CFETCH(a, b, field) a.field = counter_u64_fetch(b.field) 3584 CFETCH(gms, pmc_stats, pm_intr_ignored); 3585 CFETCH(gms, pmc_stats, pm_intr_processed); 3586 CFETCH(gms, pmc_stats, pm_intr_bufferfull); 3587 CFETCH(gms, pmc_stats, pm_syscalls); 3588 CFETCH(gms, pmc_stats, pm_syscall_errors); 3589 CFETCH(gms, pmc_stats, pm_buffer_requests); 3590 CFETCH(gms, pmc_stats, pm_buffer_requests_failed); 3591 CFETCH(gms, pmc_stats, pm_log_sweeps); 3592 #undef CFETCH 3593 error = copyout(&gms, arg, sizeof(gms)); 3594 } 3595 break; 3596 3597 3598 /* 3599 * Retrieve module version number 3600 */ 3601 3602 case PMC_OP_GETMODULEVERSION: 3603 { 3604 uint32_t cv, modv; 3605 3606 /* retrieve the client's idea of the ABI version */ 3607 if ((error = copyin(arg, &cv, sizeof(uint32_t))) != 0) 3608 break; 3609 /* don't service clients newer than our driver */ 3610 modv = PMC_VERSION; 3611 if ((cv & 0xFFFF0000) > (modv & 0xFFFF0000)) { 3612 error = EPROGMISMATCH; 3613 break; 3614 } 3615 error = copyout(&modv, arg, sizeof(int)); 3616 } 3617 break; 3618 3619 3620 /* 3621 * Retrieve the state of all the PMCs on a given 3622 * CPU. 3623 */ 3624 3625 case PMC_OP_GETPMCINFO: 3626 { 3627 int ari; 3628 struct pmc *pm; 3629 size_t pmcinfo_size; 3630 uint32_t cpu, n, npmc; 3631 struct pmc_owner *po; 3632 struct pmc_binding pb; 3633 struct pmc_classdep *pcd; 3634 struct pmc_info *p, *pmcinfo; 3635 struct pmc_op_getpmcinfo *gpi; 3636 3637 PMC_DOWNGRADE_SX(); 3638 3639 gpi = (struct pmc_op_getpmcinfo *) arg; 3640 3641 if ((error = copyin(&gpi->pm_cpu, &cpu, sizeof(cpu))) != 0) 3642 break; 3643 3644 if (cpu >= pmc_cpu_max()) { 3645 error = EINVAL; 3646 break; 3647 } 3648 3649 if (!pmc_cpu_is_active(cpu)) { 3650 error = ENXIO; 3651 break; 3652 } 3653 3654 /* switch to CPU 'cpu' */ 3655 pmc_save_cpu_binding(&pb); 3656 pmc_select_cpu(cpu); 3657 3658 npmc = md->pmd_npmc; 3659 3660 pmcinfo_size = npmc * sizeof(struct pmc_info); 3661 pmcinfo = malloc(pmcinfo_size, M_PMC, M_WAITOK); 3662 3663 p = pmcinfo; 3664 3665 for (n = 0; n < md->pmd_npmc; n++, p++) { 3666 3667 pcd = pmc_ri_to_classdep(md, n, &ari); 3668 3669 KASSERT(pcd != NULL, 3670 ("[pmc,%d] null pcd ri=%d", __LINE__, n)); 3671 3672 if ((error = pcd->pcd_describe(cpu, ari, p, &pm)) != 0) 3673 break; 3674 3675 if (PMC_ROW_DISP_IS_STANDALONE(n)) 3676 p->pm_rowdisp = PMC_DISP_STANDALONE; 3677 else if (PMC_ROW_DISP_IS_THREAD(n)) 3678 p->pm_rowdisp = PMC_DISP_THREAD; 3679 else 3680 p->pm_rowdisp = PMC_DISP_FREE; 3681 3682 p->pm_ownerpid = -1; 3683 3684 if (pm == NULL) /* no PMC associated */ 3685 continue; 3686 3687 po = pm->pm_owner; 3688 3689 KASSERT(po->po_owner != NULL, 3690 ("[pmc,%d] pmc_owner had a null proc pointer", 3691 __LINE__)); 3692 3693 p->pm_ownerpid = po->po_owner->p_pid; 3694 p->pm_mode = PMC_TO_MODE(pm); 3695 p->pm_event = pm->pm_event; 3696 p->pm_flags = pm->pm_flags; 3697 3698 if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm))) 3699 p->pm_reloadcount = 3700 pm->pm_sc.pm_reloadcount; 3701 } 3702 3703 pmc_restore_cpu_binding(&pb); 3704 3705 /* now copy out the PMC info collected */ 3706 if (error == 0) 3707 error = copyout(pmcinfo, &gpi->pm_pmcs, pmcinfo_size); 3708 3709 free(pmcinfo, M_PMC); 3710 } 3711 break; 3712 3713 3714 /* 3715 * Set the administrative state of a PMC. I.e. whether 3716 * the PMC is to be used or not. 3717 */ 3718 3719 case PMC_OP_PMCADMIN: 3720 { 3721 int cpu, ri; 3722 enum pmc_state request; 3723 struct pmc_cpu *pc; 3724 struct pmc_hw *phw; 3725 struct pmc_op_pmcadmin pma; 3726 struct pmc_binding pb; 3727 3728 sx_assert(&pmc_sx, SX_XLOCKED); 3729 3730 KASSERT(td == curthread, 3731 ("[pmc,%d] td != curthread", __LINE__)); 3732 3733 error = priv_check(td, PRIV_PMC_MANAGE); 3734 if (error) 3735 break; 3736 3737 if ((error = copyin(arg, &pma, sizeof(pma))) != 0) 3738 break; 3739 3740 cpu = pma.pm_cpu; 3741 3742 if (cpu < 0 || cpu >= (int) pmc_cpu_max()) { 3743 error = EINVAL; 3744 break; 3745 } 3746 3747 if (!pmc_cpu_is_active(cpu)) { 3748 error = ENXIO; 3749 break; 3750 } 3751 3752 request = pma.pm_state; 3753 3754 if (request != PMC_STATE_DISABLED && 3755 request != PMC_STATE_FREE) { 3756 error = EINVAL; 3757 break; 3758 } 3759 3760 ri = pma.pm_pmc; /* pmc id == row index */ 3761 if (ri < 0 || ri >= (int) md->pmd_npmc) { 3762 error = EINVAL; 3763 break; 3764 } 3765 3766 /* 3767 * We can't disable a PMC with a row-index allocated 3768 * for process virtual PMCs. 3769 */ 3770 3771 if (PMC_ROW_DISP_IS_THREAD(ri) && 3772 request == PMC_STATE_DISABLED) { 3773 error = EBUSY; 3774 break; 3775 } 3776 3777 /* 3778 * otherwise, this PMC on this CPU is either free or 3779 * in system-wide mode. 3780 */ 3781 3782 pmc_save_cpu_binding(&pb); 3783 pmc_select_cpu(cpu); 3784 3785 pc = pmc_pcpu[cpu]; 3786 phw = pc->pc_hwpmcs[ri]; 3787 3788 /* 3789 * XXX do we need some kind of 'forced' disable? 3790 */ 3791 3792 if (phw->phw_pmc == NULL) { 3793 if (request == PMC_STATE_DISABLED && 3794 (phw->phw_state & PMC_PHW_FLAG_IS_ENABLED)) { 3795 phw->phw_state &= ~PMC_PHW_FLAG_IS_ENABLED; 3796 PMC_MARK_ROW_STANDALONE(ri); 3797 } else if (request == PMC_STATE_FREE && 3798 (phw->phw_state & PMC_PHW_FLAG_IS_ENABLED) == 0) { 3799 phw->phw_state |= PMC_PHW_FLAG_IS_ENABLED; 3800 PMC_UNMARK_ROW_STANDALONE(ri); 3801 } 3802 /* other cases are a no-op */ 3803 } else 3804 error = EBUSY; 3805 3806 pmc_restore_cpu_binding(&pb); 3807 } 3808 break; 3809 3810 3811 /* 3812 * Allocate a PMC. 3813 */ 3814 3815 case PMC_OP_PMCALLOCATE: 3816 { 3817 int adjri, n; 3818 u_int cpu; 3819 uint32_t caps; 3820 struct pmc *pmc; 3821 enum pmc_mode mode; 3822 struct pmc_hw *phw; 3823 struct pmc_binding pb; 3824 struct pmc_classdep *pcd; 3825 struct pmc_op_pmcallocate pa; 3826 3827 if ((error = copyin(arg, &pa, sizeof(pa))) != 0) 3828 break; 3829 3830 caps = pa.pm_caps; 3831 mode = pa.pm_mode; 3832 cpu = pa.pm_cpu; 3833 3834 if ((mode != PMC_MODE_SS && mode != PMC_MODE_SC && 3835 mode != PMC_MODE_TS && mode != PMC_MODE_TC) || 3836 (cpu != (u_int) PMC_CPU_ANY && cpu >= pmc_cpu_max())) { 3837 error = EINVAL; 3838 break; 3839 } 3840 3841 /* 3842 * Virtual PMCs should only ask for a default CPU. 3843 * System mode PMCs need to specify a non-default CPU. 3844 */ 3845 3846 if ((PMC_IS_VIRTUAL_MODE(mode) && cpu != (u_int) PMC_CPU_ANY) || 3847 (PMC_IS_SYSTEM_MODE(mode) && cpu == (u_int) PMC_CPU_ANY)) { 3848 error = EINVAL; 3849 break; 3850 } 3851 3852 /* 3853 * Check that an inactive CPU is not being asked for. 3854 */ 3855 3856 if (PMC_IS_SYSTEM_MODE(mode) && !pmc_cpu_is_active(cpu)) { 3857 error = ENXIO; 3858 break; 3859 } 3860 3861 /* 3862 * Refuse an allocation for a system-wide PMC if this 3863 * process has been jailed, or if this process lacks 3864 * super-user credentials and the sysctl tunable 3865 * 'security.bsd.unprivileged_syspmcs' is zero. 3866 */ 3867 3868 if (PMC_IS_SYSTEM_MODE(mode)) { 3869 if (jailed(curthread->td_ucred)) { 3870 error = EPERM; 3871 break; 3872 } 3873 if (!pmc_unprivileged_syspmcs) { 3874 error = priv_check(curthread, 3875 PRIV_PMC_SYSTEM); 3876 if (error) 3877 break; 3878 } 3879 } 3880 3881 /* 3882 * Look for valid values for 'pm_flags' 3883 */ 3884 3885 if ((pa.pm_flags & ~(PMC_F_DESCENDANTS | PMC_F_LOG_PROCCSW | 3886 PMC_F_LOG_PROCEXIT | PMC_F_CALLCHAIN | 3887 PMC_F_USERCALLCHAIN)) != 0) { 3888 error = EINVAL; 3889 break; 3890 } 3891 3892 /* PMC_F_USERCALLCHAIN is only valid with PMC_F_CALLCHAIN */ 3893 if ((pa.pm_flags & (PMC_F_CALLCHAIN | PMC_F_USERCALLCHAIN)) == 3894 PMC_F_USERCALLCHAIN) { 3895 error = EINVAL; 3896 break; 3897 } 3898 3899 /* PMC_F_USERCALLCHAIN is only valid for sampling mode */ 3900 if (pa.pm_flags & PMC_F_USERCALLCHAIN && 3901 mode != PMC_MODE_TS && mode != PMC_MODE_SS) { 3902 error = EINVAL; 3903 break; 3904 } 3905 3906 /* process logging options are not allowed for system PMCs */ 3907 if (PMC_IS_SYSTEM_MODE(mode) && (pa.pm_flags & 3908 (PMC_F_LOG_PROCCSW | PMC_F_LOG_PROCEXIT))) { 3909 error = EINVAL; 3910 break; 3911 } 3912 3913 /* 3914 * All sampling mode PMCs need to be able to interrupt the 3915 * CPU. 3916 */ 3917 if (PMC_IS_SAMPLING_MODE(mode)) 3918 caps |= PMC_CAP_INTERRUPT; 3919 3920 /* A valid class specifier should have been passed in. */ 3921 pcd = pmc_class_to_classdep(pa.pm_class); 3922 if (pcd == NULL) { 3923 error = EINVAL; 3924 break; 3925 } 3926 3927 /* The requested PMC capabilities should be feasible. */ 3928 if ((pcd->pcd_caps & caps) != caps) { 3929 error = EOPNOTSUPP; 3930 break; 3931 } 3932 3933 PMCDBG4(PMC,ALL,2, "event=%d caps=0x%x mode=%d cpu=%d", 3934 pa.pm_ev, caps, mode, cpu); 3935 3936 pmc = pmc_allocate_pmc_descriptor(); 3937 pmc->pm_id = PMC_ID_MAKE_ID(cpu,pa.pm_mode,pa.pm_class, 3938 PMC_ID_INVALID); 3939 pmc->pm_event = pa.pm_ev; 3940 pmc->pm_state = PMC_STATE_FREE; 3941 pmc->pm_caps = caps; 3942 pmc->pm_flags = pa.pm_flags; 3943 3944 /* XXX set lower bound on sampling for process counters */ 3945 if (PMC_IS_SAMPLING_MODE(mode)) 3946 pmc->pm_sc.pm_reloadcount = pa.pm_count; 3947 else 3948 pmc->pm_sc.pm_initial = pa.pm_count; 3949 3950 /* switch thread to CPU 'cpu' */ 3951 pmc_save_cpu_binding(&pb); 3952 3953 #define PMC_IS_SHAREABLE_PMC(cpu, n) \ 3954 (pmc_pcpu[(cpu)]->pc_hwpmcs[(n)]->phw_state & \ 3955 PMC_PHW_FLAG_IS_SHAREABLE) 3956 #define PMC_IS_UNALLOCATED(cpu, n) \ 3957 (pmc_pcpu[(cpu)]->pc_hwpmcs[(n)]->phw_pmc == NULL) 3958 3959 if (PMC_IS_SYSTEM_MODE(mode)) { 3960 pmc_select_cpu(cpu); 3961 for (n = pcd->pcd_ri; n < (int) md->pmd_npmc; n++) { 3962 pcd = pmc_ri_to_classdep(md, n, &adjri); 3963 if (pmc_can_allocate_row(n, mode) == 0 && 3964 pmc_can_allocate_rowindex( 3965 curthread->td_proc, n, cpu) == 0 && 3966 (PMC_IS_UNALLOCATED(cpu, n) || 3967 PMC_IS_SHAREABLE_PMC(cpu, n)) && 3968 pcd->pcd_allocate_pmc(cpu, adjri, pmc, 3969 &pa) == 0) 3970 break; 3971 } 3972 } else { 3973 /* Process virtual mode */ 3974 for (n = pcd->pcd_ri; n < (int) md->pmd_npmc; n++) { 3975 pcd = pmc_ri_to_classdep(md, n, &adjri); 3976 if (pmc_can_allocate_row(n, mode) == 0 && 3977 pmc_can_allocate_rowindex( 3978 curthread->td_proc, n, 3979 PMC_CPU_ANY) == 0 && 3980 pcd->pcd_allocate_pmc(curthread->td_oncpu, 3981 adjri, pmc, &pa) == 0) 3982 break; 3983 } 3984 } 3985 3986 #undef PMC_IS_UNALLOCATED 3987 #undef PMC_IS_SHAREABLE_PMC 3988 3989 pmc_restore_cpu_binding(&pb); 3990 3991 if (n == (int) md->pmd_npmc) { 3992 pmc_destroy_pmc_descriptor(pmc); 3993 pmc = NULL; 3994 error = EINVAL; 3995 break; 3996 } 3997 3998 /* Fill in the correct value in the ID field */ 3999 pmc->pm_id = PMC_ID_MAKE_ID(cpu,mode,pa.pm_class,n); 4000 4001 PMCDBG5(PMC,ALL,2, "ev=%d class=%d mode=%d n=%d -> pmcid=%x", 4002 pmc->pm_event, pa.pm_class, mode, n, pmc->pm_id); 4003 4004 /* Process mode PMCs with logging enabled need log files */ 4005 if (pmc->pm_flags & (PMC_F_LOG_PROCEXIT | PMC_F_LOG_PROCCSW)) 4006 pmc->pm_flags |= PMC_F_NEEDS_LOGFILE; 4007 4008 /* All system mode sampling PMCs require a log file */ 4009 if (PMC_IS_SAMPLING_MODE(mode) && PMC_IS_SYSTEM_MODE(mode)) 4010 pmc->pm_flags |= PMC_F_NEEDS_LOGFILE; 4011 4012 /* 4013 * Configure global pmc's immediately 4014 */ 4015 4016 if (PMC_IS_SYSTEM_MODE(PMC_TO_MODE(pmc))) { 4017 4018 pmc_save_cpu_binding(&pb); 4019 pmc_select_cpu(cpu); 4020 4021 phw = pmc_pcpu[cpu]->pc_hwpmcs[n]; 4022 pcd = pmc_ri_to_classdep(md, n, &adjri); 4023 4024 if ((phw->phw_state & PMC_PHW_FLAG_IS_ENABLED) == 0 || 4025 (error = pcd->pcd_config_pmc(cpu, adjri, pmc)) != 0) { 4026 (void) pcd->pcd_release_pmc(cpu, adjri, pmc); 4027 pmc_destroy_pmc_descriptor(pmc); 4028 pmc = NULL; 4029 pmc_restore_cpu_binding(&pb); 4030 error = EPERM; 4031 break; 4032 } 4033 4034 pmc_restore_cpu_binding(&pb); 4035 } 4036 4037 pmc->pm_state = PMC_STATE_ALLOCATED; 4038 pmc->pm_class = pa.pm_class; 4039 4040 /* 4041 * mark row disposition 4042 */ 4043 4044 if (PMC_IS_SYSTEM_MODE(mode)) 4045 PMC_MARK_ROW_STANDALONE(n); 4046 else 4047 PMC_MARK_ROW_THREAD(n); 4048 4049 /* 4050 * Register this PMC with the current thread as its owner. 4051 */ 4052 4053 if ((error = 4054 pmc_register_owner(curthread->td_proc, pmc)) != 0) { 4055 pmc_release_pmc_descriptor(pmc); 4056 pmc_destroy_pmc_descriptor(pmc); 4057 pmc = NULL; 4058 break; 4059 } 4060 4061 4062 /* 4063 * Return the allocated index. 4064 */ 4065 4066 pa.pm_pmcid = pmc->pm_id; 4067 4068 error = copyout(&pa, arg, sizeof(pa)); 4069 } 4070 break; 4071 4072 4073 /* 4074 * Attach a PMC to a process. 4075 */ 4076 4077 case PMC_OP_PMCATTACH: 4078 { 4079 struct pmc *pm; 4080 struct proc *p; 4081 struct pmc_op_pmcattach a; 4082 4083 sx_assert(&pmc_sx, SX_XLOCKED); 4084 4085 if ((error = copyin(arg, &a, sizeof(a))) != 0) 4086 break; 4087 4088 if (a.pm_pid < 0) { 4089 error = EINVAL; 4090 break; 4091 } else if (a.pm_pid == 0) 4092 a.pm_pid = td->td_proc->p_pid; 4093 4094 if ((error = pmc_find_pmc(a.pm_pmc, &pm)) != 0) 4095 break; 4096 4097 if (PMC_IS_SYSTEM_MODE(PMC_TO_MODE(pm))) { 4098 error = EINVAL; 4099 break; 4100 } 4101 4102 /* PMCs may be (re)attached only when allocated or stopped */ 4103 if (pm->pm_state == PMC_STATE_RUNNING) { 4104 error = EBUSY; 4105 break; 4106 } else if (pm->pm_state != PMC_STATE_ALLOCATED && 4107 pm->pm_state != PMC_STATE_STOPPED) { 4108 error = EINVAL; 4109 break; 4110 } 4111 4112 /* lookup pid */ 4113 if ((p = pfind(a.pm_pid)) == NULL) { 4114 error = ESRCH; 4115 break; 4116 } 4117 4118 /* 4119 * Ignore processes that are working on exiting. 4120 */ 4121 if (p->p_flag & P_WEXIT) { 4122 error = ESRCH; 4123 PROC_UNLOCK(p); /* pfind() returns a locked process */ 4124 break; 4125 } 4126 4127 /* 4128 * we are allowed to attach a PMC to a process if 4129 * we can debug it. 4130 */ 4131 error = p_candebug(curthread, p); 4132 4133 PROC_UNLOCK(p); 4134 4135 if (error == 0) 4136 error = pmc_attach_process(p, pm); 4137 } 4138 break; 4139 4140 4141 /* 4142 * Detach an attached PMC from a process. 4143 */ 4144 4145 case PMC_OP_PMCDETACH: 4146 { 4147 struct pmc *pm; 4148 struct proc *p; 4149 struct pmc_op_pmcattach a; 4150 4151 if ((error = copyin(arg, &a, sizeof(a))) != 0) 4152 break; 4153 4154 if (a.pm_pid < 0) { 4155 error = EINVAL; 4156 break; 4157 } else if (a.pm_pid == 0) 4158 a.pm_pid = td->td_proc->p_pid; 4159 4160 if ((error = pmc_find_pmc(a.pm_pmc, &pm)) != 0) 4161 break; 4162 4163 if ((p = pfind(a.pm_pid)) == NULL) { 4164 error = ESRCH; 4165 break; 4166 } 4167 4168 /* 4169 * Treat processes that are in the process of exiting 4170 * as if they were not present. 4171 */ 4172 4173 if (p->p_flag & P_WEXIT) 4174 error = ESRCH; 4175 4176 PROC_UNLOCK(p); /* pfind() returns a locked process */ 4177 4178 if (error == 0) 4179 error = pmc_detach_process(p, pm); 4180 } 4181 break; 4182 4183 4184 /* 4185 * Retrieve the MSR number associated with the counter 4186 * 'pmc_id'. This allows processes to directly use RDPMC 4187 * instructions to read their PMCs, without the overhead of a 4188 * system call. 4189 */ 4190 4191 case PMC_OP_PMCGETMSR: 4192 { 4193 int adjri, ri; 4194 struct pmc *pm; 4195 struct pmc_target *pt; 4196 struct pmc_op_getmsr gm; 4197 struct pmc_classdep *pcd; 4198 4199 PMC_DOWNGRADE_SX(); 4200 4201 if ((error = copyin(arg, &gm, sizeof(gm))) != 0) 4202 break; 4203 4204 if ((error = pmc_find_pmc(gm.pm_pmcid, &pm)) != 0) 4205 break; 4206 4207 /* 4208 * The allocated PMC has to be a process virtual PMC, 4209 * i.e., of type MODE_T[CS]. Global PMCs can only be 4210 * read using the PMCREAD operation since they may be 4211 * allocated on a different CPU than the one we could 4212 * be running on at the time of the RDPMC instruction. 4213 * 4214 * The GETMSR operation is not allowed for PMCs that 4215 * are inherited across processes. 4216 */ 4217 4218 if (!PMC_IS_VIRTUAL_MODE(PMC_TO_MODE(pm)) || 4219 (pm->pm_flags & PMC_F_DESCENDANTS)) { 4220 error = EINVAL; 4221 break; 4222 } 4223 4224 /* 4225 * It only makes sense to use a RDPMC (or its 4226 * equivalent instruction on non-x86 architectures) on 4227 * a process that has allocated and attached a PMC to 4228 * itself. Conversely the PMC is only allowed to have 4229 * one process attached to it -- its owner. 4230 */ 4231 4232 if ((pt = LIST_FIRST(&pm->pm_targets)) == NULL || 4233 LIST_NEXT(pt, pt_next) != NULL || 4234 pt->pt_process->pp_proc != pm->pm_owner->po_owner) { 4235 error = EINVAL; 4236 break; 4237 } 4238 4239 ri = PMC_TO_ROWINDEX(pm); 4240 pcd = pmc_ri_to_classdep(md, ri, &adjri); 4241 4242 /* PMC class has no 'GETMSR' support */ 4243 if (pcd->pcd_get_msr == NULL) { 4244 error = ENOSYS; 4245 break; 4246 } 4247 4248 if ((error = (*pcd->pcd_get_msr)(adjri, &gm.pm_msr)) < 0) 4249 break; 4250 4251 if ((error = copyout(&gm, arg, sizeof(gm))) < 0) 4252 break; 4253 4254 /* 4255 * Mark our process as using MSRs. Update machine 4256 * state using a forced context switch. 4257 */ 4258 4259 pt->pt_process->pp_flags |= PMC_PP_ENABLE_MSR_ACCESS; 4260 pmc_force_context_switch(); 4261 4262 } 4263 break; 4264 4265 /* 4266 * Release an allocated PMC 4267 */ 4268 4269 case PMC_OP_PMCRELEASE: 4270 { 4271 pmc_id_t pmcid; 4272 struct pmc *pm; 4273 struct pmc_owner *po; 4274 struct pmc_op_simple sp; 4275 4276 /* 4277 * Find PMC pointer for the named PMC. 4278 * 4279 * Use pmc_release_pmc_descriptor() to switch off the 4280 * PMC, remove all its target threads, and remove the 4281 * PMC from its owner's list. 4282 * 4283 * Remove the owner record if this is the last PMC 4284 * owned. 4285 * 4286 * Free up space. 4287 */ 4288 4289 if ((error = copyin(arg, &sp, sizeof(sp))) != 0) 4290 break; 4291 4292 pmcid = sp.pm_pmcid; 4293 4294 if ((error = pmc_find_pmc(pmcid, &pm)) != 0) 4295 break; 4296 4297 po = pm->pm_owner; 4298 pmc_release_pmc_descriptor(pm); 4299 pmc_maybe_remove_owner(po); 4300 pmc_destroy_pmc_descriptor(pm); 4301 } 4302 break; 4303 4304 4305 /* 4306 * Read and/or write a PMC. 4307 */ 4308 4309 case PMC_OP_PMCRW: 4310 { 4311 int adjri; 4312 struct pmc *pm; 4313 uint32_t cpu, ri; 4314 pmc_value_t oldvalue; 4315 struct pmc_binding pb; 4316 struct pmc_op_pmcrw prw; 4317 struct pmc_classdep *pcd; 4318 struct pmc_op_pmcrw *pprw; 4319 4320 PMC_DOWNGRADE_SX(); 4321 4322 if ((error = copyin(arg, &prw, sizeof(prw))) != 0) 4323 break; 4324 4325 ri = 0; 4326 PMCDBG2(PMC,OPS,1, "rw id=%d flags=0x%x", prw.pm_pmcid, 4327 prw.pm_flags); 4328 4329 /* must have at least one flag set */ 4330 if ((prw.pm_flags & (PMC_F_OLDVALUE|PMC_F_NEWVALUE)) == 0) { 4331 error = EINVAL; 4332 break; 4333 } 4334 4335 /* locate pmc descriptor */ 4336 if ((error = pmc_find_pmc(prw.pm_pmcid, &pm)) != 0) 4337 break; 4338 4339 /* Can't read a PMC that hasn't been started. */ 4340 if (pm->pm_state != PMC_STATE_ALLOCATED && 4341 pm->pm_state != PMC_STATE_STOPPED && 4342 pm->pm_state != PMC_STATE_RUNNING) { 4343 error = EINVAL; 4344 break; 4345 } 4346 4347 /* writing a new value is allowed only for 'STOPPED' pmcs */ 4348 if (pm->pm_state == PMC_STATE_RUNNING && 4349 (prw.pm_flags & PMC_F_NEWVALUE)) { 4350 error = EBUSY; 4351 break; 4352 } 4353 4354 if (PMC_IS_VIRTUAL_MODE(PMC_TO_MODE(pm))) { 4355 4356 /* 4357 * If this PMC is attached to its owner (i.e., 4358 * the process requesting this operation) and 4359 * is running, then attempt to get an 4360 * upto-date reading from hardware for a READ. 4361 * Writes are only allowed when the PMC is 4362 * stopped, so only update the saved value 4363 * field. 4364 * 4365 * If the PMC is not running, or is not 4366 * attached to its owner, read/write to the 4367 * savedvalue field. 4368 */ 4369 4370 ri = PMC_TO_ROWINDEX(pm); 4371 pcd = pmc_ri_to_classdep(md, ri, &adjri); 4372 4373 mtx_pool_lock_spin(pmc_mtxpool, pm); 4374 cpu = curthread->td_oncpu; 4375 4376 if (prw.pm_flags & PMC_F_OLDVALUE) { 4377 if ((pm->pm_flags & PMC_F_ATTACHED_TO_OWNER) && 4378 (pm->pm_state == PMC_STATE_RUNNING)) 4379 error = (*pcd->pcd_read_pmc)(cpu, adjri, 4380 &oldvalue); 4381 else 4382 oldvalue = pm->pm_gv.pm_savedvalue; 4383 } 4384 if (prw.pm_flags & PMC_F_NEWVALUE) 4385 pm->pm_gv.pm_savedvalue = prw.pm_value; 4386 4387 mtx_pool_unlock_spin(pmc_mtxpool, pm); 4388 4389 } else { /* System mode PMCs */ 4390 cpu = PMC_TO_CPU(pm); 4391 ri = PMC_TO_ROWINDEX(pm); 4392 pcd = pmc_ri_to_classdep(md, ri, &adjri); 4393 4394 if (!pmc_cpu_is_active(cpu)) { 4395 error = ENXIO; 4396 break; 4397 } 4398 4399 /* move this thread to CPU 'cpu' */ 4400 pmc_save_cpu_binding(&pb); 4401 pmc_select_cpu(cpu); 4402 4403 critical_enter(); 4404 /* save old value */ 4405 if (prw.pm_flags & PMC_F_OLDVALUE) 4406 if ((error = (*pcd->pcd_read_pmc)(cpu, adjri, 4407 &oldvalue))) 4408 goto error; 4409 /* write out new value */ 4410 if (prw.pm_flags & PMC_F_NEWVALUE) 4411 error = (*pcd->pcd_write_pmc)(cpu, adjri, 4412 prw.pm_value); 4413 error: 4414 critical_exit(); 4415 pmc_restore_cpu_binding(&pb); 4416 if (error) 4417 break; 4418 } 4419 4420 pprw = (struct pmc_op_pmcrw *) arg; 4421 4422 #ifdef HWPMC_DEBUG 4423 if (prw.pm_flags & PMC_F_NEWVALUE) 4424 PMCDBG3(PMC,OPS,2, "rw id=%d new %jx -> old %jx", 4425 ri, prw.pm_value, oldvalue); 4426 else if (prw.pm_flags & PMC_F_OLDVALUE) 4427 PMCDBG2(PMC,OPS,2, "rw id=%d -> old %jx", ri, oldvalue); 4428 #endif 4429 4430 /* return old value if requested */ 4431 if (prw.pm_flags & PMC_F_OLDVALUE) 4432 if ((error = copyout(&oldvalue, &pprw->pm_value, 4433 sizeof(prw.pm_value)))) 4434 break; 4435 4436 } 4437 break; 4438 4439 4440 /* 4441 * Set the sampling rate for a sampling mode PMC and the 4442 * initial count for a counting mode PMC. 4443 */ 4444 4445 case PMC_OP_PMCSETCOUNT: 4446 { 4447 struct pmc *pm; 4448 struct pmc_op_pmcsetcount sc; 4449 4450 PMC_DOWNGRADE_SX(); 4451 4452 if ((error = copyin(arg, &sc, sizeof(sc))) != 0) 4453 break; 4454 4455 if ((error = pmc_find_pmc(sc.pm_pmcid, &pm)) != 0) 4456 break; 4457 4458 if (pm->pm_state == PMC_STATE_RUNNING) { 4459 error = EBUSY; 4460 break; 4461 } 4462 4463 if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm))) 4464 pm->pm_sc.pm_reloadcount = sc.pm_count; 4465 else 4466 pm->pm_sc.pm_initial = sc.pm_count; 4467 } 4468 break; 4469 4470 4471 /* 4472 * Start a PMC. 4473 */ 4474 4475 case PMC_OP_PMCSTART: 4476 { 4477 pmc_id_t pmcid; 4478 struct pmc *pm; 4479 struct pmc_op_simple sp; 4480 4481 sx_assert(&pmc_sx, SX_XLOCKED); 4482 4483 if ((error = copyin(arg, &sp, sizeof(sp))) != 0) 4484 break; 4485 4486 pmcid = sp.pm_pmcid; 4487 4488 if ((error = pmc_find_pmc(pmcid, &pm)) != 0) 4489 break; 4490 4491 KASSERT(pmcid == pm->pm_id, 4492 ("[pmc,%d] pmcid %x != id %x", __LINE__, 4493 pm->pm_id, pmcid)); 4494 4495 if (pm->pm_state == PMC_STATE_RUNNING) /* already running */ 4496 break; 4497 else if (pm->pm_state != PMC_STATE_STOPPED && 4498 pm->pm_state != PMC_STATE_ALLOCATED) { 4499 error = EINVAL; 4500 break; 4501 } 4502 4503 error = pmc_start(pm); 4504 } 4505 break; 4506 4507 4508 /* 4509 * Stop a PMC. 4510 */ 4511 4512 case PMC_OP_PMCSTOP: 4513 { 4514 pmc_id_t pmcid; 4515 struct pmc *pm; 4516 struct pmc_op_simple sp; 4517 4518 PMC_DOWNGRADE_SX(); 4519 4520 if ((error = copyin(arg, &sp, sizeof(sp))) != 0) 4521 break; 4522 4523 pmcid = sp.pm_pmcid; 4524 4525 /* 4526 * Mark the PMC as inactive and invoke the MD stop 4527 * routines if needed. 4528 */ 4529 4530 if ((error = pmc_find_pmc(pmcid, &pm)) != 0) 4531 break; 4532 4533 KASSERT(pmcid == pm->pm_id, 4534 ("[pmc,%d] pmc id %x != pmcid %x", __LINE__, 4535 pm->pm_id, pmcid)); 4536 4537 if (pm->pm_state == PMC_STATE_STOPPED) /* already stopped */ 4538 break; 4539 else if (pm->pm_state != PMC_STATE_RUNNING) { 4540 error = EINVAL; 4541 break; 4542 } 4543 4544 error = pmc_stop(pm); 4545 } 4546 break; 4547 4548 4549 /* 4550 * Write a user supplied value to the log file. 4551 */ 4552 4553 case PMC_OP_WRITELOG: 4554 { 4555 struct pmc_op_writelog wl; 4556 struct pmc_owner *po; 4557 4558 PMC_DOWNGRADE_SX(); 4559 4560 if ((error = copyin(arg, &wl, sizeof(wl))) != 0) 4561 break; 4562 4563 if ((po = pmc_find_owner_descriptor(td->td_proc)) == NULL) { 4564 error = EINVAL; 4565 break; 4566 } 4567 4568 if ((po->po_flags & PMC_PO_OWNS_LOGFILE) == 0) { 4569 error = EINVAL; 4570 break; 4571 } 4572 4573 error = pmclog_process_userlog(po, &wl); 4574 } 4575 break; 4576 4577 4578 default: 4579 error = EINVAL; 4580 break; 4581 } 4582 4583 if (is_sx_downgraded) 4584 sx_sunlock(&pmc_sx); 4585 else 4586 sx_xunlock(&pmc_sx); 4587 done_syscall: 4588 if (error) 4589 counter_u64_add(pmc_stats.pm_syscall_errors, 1); 4590 4591 return (error); 4592 } 4593 4594 /* 4595 * Helper functions 4596 */ 4597 4598 4599 /* 4600 * Mark the thread as needing callchain capture and post an AST. The 4601 * actual callchain capture will be done in a context where it is safe 4602 * to take page faults. 4603 */ 4604 4605 static void 4606 pmc_post_callchain_callback(void) 4607 { 4608 struct thread *td; 4609 4610 td = curthread; 4611 4612 /* 4613 * If there is multiple PMCs for the same interrupt ignore new post 4614 */ 4615 if (td->td_pflags & TDP_CALLCHAIN) 4616 return; 4617 4618 /* 4619 * Mark this thread as needing callchain capture. 4620 * `td->td_pflags' will be safe to touch because this thread 4621 * was in user space when it was interrupted. 4622 */ 4623 td->td_pflags |= TDP_CALLCHAIN; 4624 4625 /* 4626 * Don't let this thread migrate between CPUs until callchain 4627 * capture completes. 4628 */ 4629 sched_pin(); 4630 4631 return; 4632 } 4633 4634 /* 4635 * Find a free slot in the per-cpu array of samples and capture the 4636 * current callchain there. If a sample was successfully added, a bit 4637 * is set in mask 'pmc_cpumask' denoting that the DO_SAMPLES hook 4638 * needs to be invoked from the clock handler. 4639 * 4640 * This function is meant to be called from an NMI handler. It cannot 4641 * use any of the locking primitives supplied by the OS. 4642 */ 4643 4644 static int 4645 pmc_add_sample(int ring, struct pmc *pm, struct trapframe *tf) 4646 { 4647 int error, cpu, callchaindepth, inuserspace; 4648 struct thread *td; 4649 struct pmc_sample *ps; 4650 struct pmc_samplebuffer *psb; 4651 4652 error = 0; 4653 4654 /* 4655 * Allocate space for a sample buffer. 4656 */ 4657 cpu = curcpu; 4658 psb = pmc_pcpu[cpu]->pc_sb[ring]; 4659 inuserspace = TRAPF_USERMODE(tf); 4660 ps = psb->ps_write; 4661 if (ps->ps_nsamples == PMC_SAMPLE_INUSE) { 4662 counter_u64_add(ps->ps_pmc->pm_runcount, -1); 4663 counter_u64_add(pmc_stats.pm_overwrites, 1); 4664 ps->ps_nsamples = 0; 4665 } else if (ps->ps_nsamples) { /* in use, reader hasn't caught up */ 4666 pm->pm_pcpu_state[cpu].pps_stalled = 1; 4667 counter_u64_add(pmc_stats.pm_intr_bufferfull, 1); 4668 PMCDBG6(SAM,INT,1,"(spc) cpu=%d pm=%p tf=%p um=%d wr=%d rd=%d", 4669 cpu, pm, (void *) tf, inuserspace, 4670 (int) (psb->ps_write - psb->ps_samples), 4671 (int) (psb->ps_read - psb->ps_samples)); 4672 callchaindepth = 1; 4673 error = ENOMEM; 4674 goto done; 4675 } 4676 4677 /* Fill in entry. */ 4678 PMCDBG6(SAM,INT,1,"cpu=%d pm=%p tf=%p um=%d wr=%d rd=%d", cpu, pm, 4679 (void *) tf, inuserspace, 4680 (int) (psb->ps_write - psb->ps_samples), 4681 (int) (psb->ps_read - psb->ps_samples)); 4682 4683 KASSERT(counter_u64_fetch(pm->pm_runcount) >= 0, 4684 ("[pmc,%d] pm=%p runcount %ld", __LINE__, (void *) pm, 4685 (unsigned long)counter_u64_fetch(pm->pm_runcount))); 4686 4687 counter_u64_add(pm->pm_runcount, 1); /* hold onto PMC */ 4688 4689 td = curthread; 4690 ps->ps_pmc = pm; 4691 ps->ps_td = td; 4692 ps->ps_pid = td->td_proc->p_pid; 4693 ps->ps_tid = td->td_tid; 4694 ps->ps_tsc = pmc_rdtsc(); 4695 4696 ps->ps_cpu = cpu; 4697 ps->ps_flags = inuserspace ? PMC_CC_F_USERSPACE : 0; 4698 4699 callchaindepth = (pm->pm_flags & PMC_F_CALLCHAIN) ? 4700 pmc_callchaindepth : 1; 4701 4702 if (callchaindepth == 1) 4703 ps->ps_pc[0] = PMC_TRAPFRAME_TO_PC(tf); 4704 else { 4705 /* 4706 * Kernel stack traversals can be done immediately, 4707 * while we defer to an AST for user space traversals. 4708 */ 4709 if (!inuserspace) { 4710 callchaindepth = 4711 pmc_save_kernel_callchain(ps->ps_pc, 4712 callchaindepth, tf); 4713 } else { 4714 pmc_post_callchain_callback(); 4715 callchaindepth = PMC_SAMPLE_INUSE; 4716 } 4717 } 4718 4719 ps->ps_nsamples = callchaindepth; /* mark entry as in use */ 4720 if (ring == PMC_UR) { 4721 ps->ps_nsamples_actual = callchaindepth; /* mark entry as in use */ 4722 ps->ps_nsamples = PMC_SAMPLE_INUSE; 4723 } else 4724 ps->ps_nsamples = callchaindepth; /* mark entry as in use */ 4725 /* increment write pointer, modulo ring buffer size */ 4726 ps++; 4727 if (ps == psb->ps_fence) 4728 psb->ps_write = psb->ps_samples; 4729 else 4730 psb->ps_write = ps; 4731 4732 done: 4733 /* mark CPU as needing processing */ 4734 if (callchaindepth != PMC_SAMPLE_INUSE) 4735 DPCPU_SET(pmc_sampled, 1); 4736 4737 return (error); 4738 } 4739 4740 /* 4741 * Interrupt processing. 4742 * 4743 * This function is meant to be called from an NMI handler. It cannot 4744 * use any of the locking primitives supplied by the OS. 4745 */ 4746 4747 int 4748 pmc_process_interrupt(int ring, struct pmc *pm, struct trapframe *tf) 4749 { 4750 struct thread *td; 4751 4752 td = curthread; 4753 if ((pm->pm_flags & PMC_F_USERCALLCHAIN) && 4754 (td->td_proc->p_flag & P_KPROC) == 0 && 4755 !TRAPF_USERMODE(tf)) { 4756 atomic_add_int(&td->td_pmcpend, 1); 4757 return (pmc_add_sample(PMC_UR, pm, tf)); 4758 } 4759 return (pmc_add_sample(ring, pm, tf)); 4760 } 4761 4762 /* 4763 * Capture a user call chain. This function will be called from ast() 4764 * before control returns to userland and before the process gets 4765 * rescheduled. 4766 */ 4767 4768 static void 4769 pmc_capture_user_callchain(int cpu, int ring, struct trapframe *tf) 4770 { 4771 struct pmc *pm; 4772 struct thread *td; 4773 struct pmc_sample *ps, *ps_end; 4774 struct pmc_samplebuffer *psb; 4775 int nsamples, nrecords, pass; 4776 #ifdef INVARIANTS 4777 int ncallchains; 4778 int nfree; 4779 #endif 4780 4781 psb = pmc_pcpu[cpu]->pc_sb[ring]; 4782 td = curthread; 4783 4784 KASSERT(td->td_pflags & TDP_CALLCHAIN, 4785 ("[pmc,%d] Retrieving callchain for thread that doesn't want it", 4786 __LINE__)); 4787 4788 #ifdef INVARIANTS 4789 ncallchains = 0; 4790 nfree = 0; 4791 #endif 4792 nrecords = INT_MAX; 4793 pass = 0; 4794 restart: 4795 if (ring == PMC_UR) 4796 nrecords = atomic_readandclear_32(&td->td_pmcpend); 4797 4798 /* 4799 * Iterate through all deferred callchain requests. 4800 * Walk from the current read pointer to the current 4801 * write pointer. 4802 */ 4803 4804 ps = psb->ps_read; 4805 ps_end = psb->ps_write; 4806 do { 4807 #ifdef INVARIANTS 4808 if (ps->ps_nsamples == PMC_SAMPLE_FREE) { 4809 nfree++; 4810 goto next; 4811 } 4812 4813 if ((ps->ps_pmc == NULL) || 4814 (ps->ps_pmc->pm_state != PMC_STATE_RUNNING)) 4815 nfree++; 4816 #endif 4817 if (ps->ps_nsamples != PMC_SAMPLE_INUSE) 4818 goto next; 4819 if (ps->ps_td != td) 4820 goto next; 4821 4822 KASSERT(ps->ps_cpu == cpu, 4823 ("[pmc,%d] cpu mismatch ps_cpu=%d pcpu=%d", __LINE__, 4824 ps->ps_cpu, PCPU_GET(cpuid))); 4825 4826 pm = ps->ps_pmc; 4827 4828 KASSERT(pm->pm_flags & PMC_F_CALLCHAIN, 4829 ("[pmc,%d] Retrieving callchain for PMC that doesn't " 4830 "want it", __LINE__)); 4831 4832 KASSERT(counter_u64_fetch(pm->pm_runcount) > 0, 4833 ("[pmc,%d] runcount %ld", __LINE__, (unsigned long)counter_u64_fetch(pm->pm_runcount))); 4834 4835 if (ring == PMC_UR) { 4836 nsamples = ps->ps_nsamples_actual; 4837 counter_u64_add(pmc_stats.pm_merges, 1); 4838 } else 4839 nsamples = 0; 4840 4841 /* 4842 * Retrieve the callchain and mark the sample buffer 4843 * as 'processable' by the timer tick sweep code. 4844 */ 4845 4846 #ifdef INVARIANTS 4847 ncallchains++; 4848 #endif 4849 4850 if (__predict_true(nsamples < pmc_callchaindepth - 1)) 4851 nsamples += pmc_save_user_callchain(ps->ps_pc + nsamples, 4852 pmc_callchaindepth - nsamples - 1, tf); 4853 wmb(); 4854 ps->ps_nsamples = nsamples; 4855 if (nrecords-- == 1) 4856 break; 4857 next: 4858 /* increment the pointer, modulo sample ring size */ 4859 if (++ps == psb->ps_fence) 4860 ps = psb->ps_samples; 4861 } while (ps != ps_end); 4862 if (__predict_false(ring == PMC_UR && td->td_pmcpend)) { 4863 if (pass == 0) { 4864 pass = 1; 4865 goto restart; 4866 } 4867 /* only collect samples for this part once */ 4868 td->td_pmcpend = 0; 4869 } 4870 4871 #ifdef INVARIANTS 4872 if (ring == PMC_HR) 4873 KASSERT(ncallchains > 0 || nfree > 0, 4874 ("[pmc,%d] cpu %d didn't find a sample to collect", __LINE__, 4875 cpu)); 4876 #endif 4877 4878 /* mark CPU as needing processing */ 4879 DPCPU_SET(pmc_sampled, 1); 4880 } 4881 4882 4883 static void 4884 pmc_flush_ring(int cpu, int ring) 4885 { 4886 struct pmc *pm; 4887 struct pmc_sample *ps; 4888 struct pmc_samplebuffer *psb; 4889 int n; 4890 4891 psb = pmc_pcpu[cpu]->pc_sb[ring]; 4892 4893 for (n = 0; n < pmc_nsamples; n++) { /* bound on #iterations */ 4894 4895 ps = psb->ps_read; 4896 if (ps->ps_nsamples == PMC_SAMPLE_FREE) 4897 goto next; 4898 pm = ps->ps_pmc; 4899 counter_u64_add(pm->pm_runcount, -1); 4900 ps->ps_nsamples = PMC_SAMPLE_FREE; 4901 /* increment read pointer, modulo sample size */ 4902 next: 4903 if (++ps == psb->ps_fence) 4904 psb->ps_read = psb->ps_samples; 4905 else 4906 psb->ps_read = ps; 4907 } 4908 } 4909 4910 void 4911 pmc_flush_samples(int cpu) 4912 { 4913 int n; 4914 4915 for (n = 0; n < PMC_NUM_SR; n++) 4916 pmc_flush_ring(cpu, n); 4917 } 4918 4919 4920 /* 4921 * Process saved PC samples. 4922 */ 4923 4924 static void 4925 pmc_process_samples(int cpu, int ring) 4926 { 4927 struct pmc *pm; 4928 int adjri, n; 4929 struct thread *td; 4930 struct pmc_owner *po; 4931 struct pmc_sample *ps; 4932 struct pmc_classdep *pcd; 4933 struct pmc_samplebuffer *psb; 4934 4935 KASSERT(PCPU_GET(cpuid) == cpu, 4936 ("[pmc,%d] not on the correct CPU pcpu=%d cpu=%d", __LINE__, 4937 PCPU_GET(cpuid), cpu)); 4938 4939 psb = pmc_pcpu[cpu]->pc_sb[ring]; 4940 4941 for (n = 0; n < pmc_nsamples; n++) { /* bound on #iterations */ 4942 4943 ps = psb->ps_read; 4944 if (ps->ps_nsamples == PMC_SAMPLE_FREE) 4945 break; 4946 4947 pm = ps->ps_pmc; 4948 4949 KASSERT(counter_u64_fetch(pm->pm_runcount) > 0, 4950 ("[pmc,%d] pm=%p runcount %ld", __LINE__, (void *) pm, 4951 (unsigned long)counter_u64_fetch(pm->pm_runcount))); 4952 4953 po = pm->pm_owner; 4954 4955 KASSERT(PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)), 4956 ("[pmc,%d] pmc=%p non-sampling mode=%d", __LINE__, 4957 pm, PMC_TO_MODE(pm))); 4958 4959 /* Ignore PMCs that have been switched off */ 4960 if (pm->pm_state != PMC_STATE_RUNNING) 4961 goto entrydone; 4962 4963 /* If there is a pending AST wait for completion */ 4964 if (ps->ps_nsamples == PMC_SAMPLE_INUSE) { 4965 /* Need a rescan at a later time. */ 4966 DPCPU_SET(pmc_sampled, 1); 4967 break; 4968 } 4969 4970 PMCDBG6(SAM,OPS,1,"cpu=%d pm=%p n=%d fl=%x wr=%d rd=%d", cpu, 4971 pm, ps->ps_nsamples, ps->ps_flags, 4972 (int) (psb->ps_write - psb->ps_samples), 4973 (int) (psb->ps_read - psb->ps_samples)); 4974 4975 /* 4976 * If this is a process-mode PMC that is attached to 4977 * its owner, and if the PC is in user mode, update 4978 * profiling statistics like timer-based profiling 4979 * would have done. 4980 * 4981 * Otherwise, this is either a sampling-mode PMC that 4982 * is attached to a different process than its owner, 4983 * or a system-wide sampling PMC. Dispatch a log 4984 * entry to the PMC's owner process. 4985 */ 4986 if (pm->pm_flags & PMC_F_ATTACHED_TO_OWNER) { 4987 if (ps->ps_flags & PMC_CC_F_USERSPACE) { 4988 td = FIRST_THREAD_IN_PROC(po->po_owner); 4989 addupc_intr(td, ps->ps_pc[0], 1); 4990 } 4991 } else 4992 pmclog_process_callchain(pm, ps); 4993 4994 entrydone: 4995 ps->ps_nsamples = 0; /* mark entry as free */ 4996 counter_u64_add(pm->pm_runcount, -1); 4997 4998 /* increment read pointer, modulo sample size */ 4999 if (++ps == psb->ps_fence) 5000 psb->ps_read = psb->ps_samples; 5001 else 5002 psb->ps_read = ps; 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 5057 static void 5058 pmc_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 counter_u64_add(pm->pm_runcount, -1); 5186 5187 KASSERT((int) counter_u64_fetch(pm->pm_runcount) >= 0, 5188 ("[pmc,%d] runcount is %d", __LINE__, ri)); 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 5240 static void 5241 pmc_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 5328 static void 5329 pmc_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 5340 static void 5341 pmc_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 5352 static void 5353 pmc_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 5364 static void 5365 pmc_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 5386 static void 5387 pmc_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 5406 static void 5407 pmc_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 */ 5427 static const char * 5428 pmc_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 */ 5445 struct pmc_mdep * 5446 pmc_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 5462 void 5463 pmc_mdep_free(struct pmc_mdep *md) 5464 { 5465 pmc_soft_finalize(md); 5466 free(md, M_PMC); 5467 } 5468 5469 static int 5470 generic_switch_in(struct pmc_cpu *pc, struct pmc_process *pp) 5471 { 5472 (void) pc; (void) pp; 5473 5474 return (0); 5475 } 5476 5477 static int 5478 generic_switch_out(struct pmc_cpu *pc, struct pmc_process *pp) 5479 { 5480 (void) pc; (void) pp; 5481 5482 return (0); 5483 } 5484 5485 static struct pmc_mdep * 5486 pmc_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 5502 static void 5503 pmc_generic_cpu_finalize(struct pmc_mdep *md) 5504 { 5505 (void) md; 5506 } 5507 5508 5509 static int 5510 pmc_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 5572 if (pmc_callchaindepth <= 0 || 5573 pmc_callchaindepth > PMC_CALLCHAIN_DEPTH_MAX) { 5574 (void) printf("hwpmc: tunable \"callchaindepth\"=%d out of " 5575 "range - using %d.\n", pmc_callchaindepth, 5576 PMC_CALLCHAIN_DEPTH_MAX); 5577 pmc_callchaindepth = PMC_CALLCHAIN_DEPTH_MAX; 5578 } 5579 5580 md = pmc_md_initialize(); 5581 if (md == NULL) { 5582 /* Default to generic CPU. */ 5583 md = pmc_generic_cpu_initialize(); 5584 if (md == NULL) 5585 return (ENOSYS); 5586 } 5587 5588 KASSERT(md->pmd_nclass >= 1 && md->pmd_npmc >= 1, 5589 ("[pmc,%d] no classes or pmcs", __LINE__)); 5590 5591 /* Compute the map from row-indices to classdep pointers. */ 5592 pmc_rowindex_to_classdep = malloc(sizeof(struct pmc_classdep *) * 5593 md->pmd_npmc, M_PMC, M_WAITOK|M_ZERO); 5594 5595 for (n = 0; n < md->pmd_npmc; n++) 5596 pmc_rowindex_to_classdep[n] = NULL; 5597 for (ri = c = 0; c < md->pmd_nclass; c++) { 5598 pcd = &md->pmd_classdep[c]; 5599 for (n = 0; n < pcd->pcd_num; n++, ri++) 5600 pmc_rowindex_to_classdep[ri] = pcd; 5601 } 5602 5603 KASSERT(ri == md->pmd_npmc, 5604 ("[pmc,%d] npmc miscomputed: ri=%d, md->npmc=%d", __LINE__, 5605 ri, md->pmd_npmc)); 5606 5607 maxcpu = pmc_cpu_max(); 5608 5609 /* allocate space for the per-cpu array */ 5610 pmc_pcpu = malloc(maxcpu * sizeof(struct pmc_cpu *), M_PMC, 5611 M_WAITOK|M_ZERO); 5612 5613 /* per-cpu 'saved values' for managing process-mode PMCs */ 5614 pmc_pcpu_saved = malloc(sizeof(pmc_value_t) * maxcpu * md->pmd_npmc, 5615 M_PMC, M_WAITOK); 5616 5617 /* Perform CPU-dependent initialization. */ 5618 pmc_save_cpu_binding(&pb); 5619 error = 0; 5620 for (cpu = 0; error == 0 && cpu < maxcpu; cpu++) { 5621 if (!pmc_cpu_is_active(cpu)) 5622 continue; 5623 pmc_select_cpu(cpu); 5624 pmc_pcpu[cpu] = malloc(sizeof(struct pmc_cpu) + 5625 md->pmd_npmc * sizeof(struct pmc_hw *), M_PMC, 5626 M_WAITOK|M_ZERO); 5627 if (md->pmd_pcpu_init) 5628 error = md->pmd_pcpu_init(md, cpu); 5629 for (n = 0; error == 0 && n < md->pmd_nclass; n++) 5630 error = md->pmd_classdep[n].pcd_pcpu_init(md, cpu); 5631 } 5632 pmc_restore_cpu_binding(&pb); 5633 5634 if (error) 5635 return (error); 5636 5637 /* allocate space for the sample array */ 5638 for (cpu = 0; cpu < maxcpu; cpu++) { 5639 if (!pmc_cpu_is_active(cpu)) 5640 continue; 5641 pc = pcpu_find(cpu); 5642 domain = pc->pc_domain; 5643 sb = malloc_domain(sizeof(struct pmc_samplebuffer) + 5644 pmc_nsamples * sizeof(struct pmc_sample), M_PMC, domain, 5645 M_WAITOK|M_ZERO); 5646 sb->ps_read = sb->ps_write = sb->ps_samples; 5647 sb->ps_fence = sb->ps_samples + pmc_nsamples; 5648 5649 KASSERT(pmc_pcpu[cpu] != NULL, 5650 ("[pmc,%d] cpu=%d Null per-cpu data", __LINE__, cpu)); 5651 5652 sb->ps_callchains = malloc_domain(pmc_callchaindepth * pmc_nsamples * 5653 sizeof(uintptr_t), M_PMC, 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_domain(sizeof(struct pmc_samplebuffer) + 5662 pmc_nsamples * sizeof(struct pmc_sample), M_PMC, domain, 5663 M_WAITOK|M_ZERO); 5664 sb->ps_read = sb->ps_write = sb->ps_samples; 5665 sb->ps_fence = sb->ps_samples + pmc_nsamples; 5666 5667 KASSERT(pmc_pcpu[cpu] != NULL, 5668 ("[pmc,%d] cpu=%d Null per-cpu data", __LINE__, cpu)); 5669 5670 sb->ps_callchains = malloc_domain(pmc_callchaindepth * pmc_nsamples * 5671 sizeof(uintptr_t), M_PMC, domain, M_WAITOK|M_ZERO); 5672 5673 for (n = 0, ps = sb->ps_samples; n < pmc_nsamples; n++, ps++) 5674 ps->ps_pc = sb->ps_callchains + 5675 (n * pmc_callchaindepth); 5676 5677 pmc_pcpu[cpu]->pc_sb[PMC_SR] = sb; 5678 5679 sb = malloc_domain(sizeof(struct pmc_samplebuffer) + 5680 pmc_nsamples * sizeof(struct pmc_sample), M_PMC, domain, 5681 M_WAITOK|M_ZERO); 5682 sb->ps_read = sb->ps_write = sb->ps_samples; 5683 sb->ps_fence = sb->ps_samples + pmc_nsamples; 5684 5685 KASSERT(pmc_pcpu[cpu] != NULL, 5686 ("[pmc,%d] cpu=%d Null per-cpu data", __LINE__, cpu)); 5687 5688 sb->ps_callchains = malloc_domain(pmc_callchaindepth * pmc_nsamples * 5689 sizeof(uintptr_t), M_PMC, domain, M_WAITOK|M_ZERO); 5690 5691 for (n = 0, ps = sb->ps_samples; n < pmc_nsamples; n++, ps++) 5692 ps->ps_pc = sb->ps_callchains + 5693 (n * pmc_callchaindepth); 5694 5695 pmc_pcpu[cpu]->pc_sb[PMC_UR] = sb; 5696 } 5697 5698 /* allocate space for the row disposition array */ 5699 pmc_pmcdisp = malloc(sizeof(enum pmc_mode) * md->pmd_npmc, 5700 M_PMC, M_WAITOK|M_ZERO); 5701 5702 /* mark all PMCs as available */ 5703 for (n = 0; n < (int) md->pmd_npmc; n++) 5704 PMC_MARK_ROW_FREE(n); 5705 5706 /* allocate thread hash tables */ 5707 pmc_ownerhash = hashinit(pmc_hashsize, M_PMC, 5708 &pmc_ownerhashmask); 5709 5710 pmc_processhash = hashinit(pmc_hashsize, M_PMC, 5711 &pmc_processhashmask); 5712 mtx_init(&pmc_processhash_mtx, "pmc-process-hash", "pmc-leaf", 5713 MTX_SPIN); 5714 5715 CK_LIST_INIT(&pmc_ss_owners); 5716 pmc_ss_count = 0; 5717 5718 /* allocate a pool of spin mutexes */ 5719 pmc_mtxpool = mtx_pool_create("pmc-leaf", pmc_mtxpool_size, 5720 MTX_SPIN); 5721 5722 PMCDBG4(MOD,INI,1, "pmc_ownerhash=%p, mask=0x%lx " 5723 "targethash=%p mask=0x%lx", pmc_ownerhash, pmc_ownerhashmask, 5724 pmc_processhash, pmc_processhashmask); 5725 5726 /* Initialize a spin mutex for the thread free list. */ 5727 mtx_init(&pmc_threadfreelist_mtx, "pmc-threadfreelist", "pmc-leaf", 5728 MTX_SPIN); 5729 5730 /* 5731 * Initialize the callout to monitor the thread free list. 5732 * This callout will also handle the initial population of the list. 5733 */ 5734 taskqgroup_config_gtask_init(NULL, &free_gtask, pmc_thread_descriptor_pool_free_task, "thread descriptor pool free task"); 5735 5736 /* register process {exit,fork,exec} handlers */ 5737 pmc_exit_tag = EVENTHANDLER_REGISTER(process_exit, 5738 pmc_process_exit, NULL, EVENTHANDLER_PRI_ANY); 5739 pmc_fork_tag = EVENTHANDLER_REGISTER(process_fork, 5740 pmc_process_fork, NULL, EVENTHANDLER_PRI_ANY); 5741 5742 /* register kld event handlers */ 5743 pmc_kld_load_tag = EVENTHANDLER_REGISTER(kld_load, pmc_kld_load, 5744 NULL, EVENTHANDLER_PRI_ANY); 5745 pmc_kld_unload_tag = EVENTHANDLER_REGISTER(kld_unload, pmc_kld_unload, 5746 NULL, EVENTHANDLER_PRI_ANY); 5747 5748 /* initialize logging */ 5749 pmclog_initialize(); 5750 5751 /* set hook functions */ 5752 pmc_intr = md->pmd_intr; 5753 wmb(); 5754 pmc_hook = pmc_hook_handler; 5755 5756 if (error == 0) { 5757 printf(PMC_MODULE_NAME ":"); 5758 for (n = 0; n < (int) md->pmd_nclass; n++) { 5759 pcd = &md->pmd_classdep[n]; 5760 printf(" %s/%d/%d/0x%b", 5761 pmc_name_of_pmcclass(pcd->pcd_class), 5762 pcd->pcd_num, 5763 pcd->pcd_width, 5764 pcd->pcd_caps, 5765 "\20" 5766 "\1INT\2USR\3SYS\4EDG\5THR" 5767 "\6REA\7WRI\10INV\11QUA\12PRC" 5768 "\13TAG\14CSC"); 5769 } 5770 printf("\n"); 5771 } 5772 5773 return (error); 5774 } 5775 5776 /* prepare to be unloaded */ 5777 static void 5778 pmc_cleanup(void) 5779 { 5780 int c, cpu; 5781 unsigned int maxcpu; 5782 struct pmc_ownerhash *ph; 5783 struct pmc_owner *po, *tmp; 5784 struct pmc_binding pb; 5785 #ifdef HWPMC_DEBUG 5786 struct pmc_processhash *prh; 5787 #endif 5788 5789 PMCDBG0(MOD,INI,0, "cleanup"); 5790 5791 /* switch off sampling */ 5792 CPU_FOREACH(cpu) 5793 DPCPU_ID_SET(cpu, pmc_sampled, 0); 5794 pmc_intr = NULL; 5795 5796 sx_xlock(&pmc_sx); 5797 if (pmc_hook == NULL) { /* being unloaded already */ 5798 sx_xunlock(&pmc_sx); 5799 return; 5800 } 5801 5802 pmc_hook = NULL; /* prevent new threads from entering module */ 5803 5804 /* deregister event handlers */ 5805 EVENTHANDLER_DEREGISTER(process_fork, pmc_fork_tag); 5806 EVENTHANDLER_DEREGISTER(process_exit, pmc_exit_tag); 5807 EVENTHANDLER_DEREGISTER(kld_load, pmc_kld_load_tag); 5808 EVENTHANDLER_DEREGISTER(kld_unload, pmc_kld_unload_tag); 5809 5810 /* send SIGBUS to all owner threads, free up allocations */ 5811 if (pmc_ownerhash) 5812 for (ph = pmc_ownerhash; 5813 ph <= &pmc_ownerhash[pmc_ownerhashmask]; 5814 ph++) { 5815 LIST_FOREACH_SAFE(po, ph, po_next, tmp) { 5816 pmc_remove_owner(po); 5817 5818 /* send SIGBUS to owner processes */ 5819 PMCDBG3(MOD,INI,2, "cleanup signal proc=%p " 5820 "(%d, %s)", po->po_owner, 5821 po->po_owner->p_pid, 5822 po->po_owner->p_comm); 5823 5824 PROC_LOCK(po->po_owner); 5825 kern_psignal(po->po_owner, SIGBUS); 5826 PROC_UNLOCK(po->po_owner); 5827 5828 pmc_destroy_owner_descriptor(po); 5829 } 5830 } 5831 5832 /* reclaim allocated data structures */ 5833 mtx_destroy(&pmc_threadfreelist_mtx); 5834 pmc_thread_descriptor_pool_drain(); 5835 5836 if (pmc_mtxpool) 5837 mtx_pool_destroy(&pmc_mtxpool); 5838 5839 mtx_destroy(&pmc_processhash_mtx); 5840 taskqgroup_config_gtask_deinit(&free_gtask); 5841 if (pmc_processhash) { 5842 #ifdef HWPMC_DEBUG 5843 struct pmc_process *pp; 5844 5845 PMCDBG0(MOD,INI,3, "destroy process hash"); 5846 for (prh = pmc_processhash; 5847 prh <= &pmc_processhash[pmc_processhashmask]; 5848 prh++) 5849 LIST_FOREACH(pp, prh, pp_next) 5850 PMCDBG1(MOD,INI,3, "pid=%d", pp->pp_proc->p_pid); 5851 #endif 5852 5853 hashdestroy(pmc_processhash, M_PMC, pmc_processhashmask); 5854 pmc_processhash = NULL; 5855 } 5856 5857 if (pmc_ownerhash) { 5858 PMCDBG0(MOD,INI,3, "destroy owner hash"); 5859 hashdestroy(pmc_ownerhash, M_PMC, pmc_ownerhashmask); 5860 pmc_ownerhash = NULL; 5861 } 5862 5863 KASSERT(CK_LIST_EMPTY(&pmc_ss_owners), 5864 ("[pmc,%d] Global SS owner list not empty", __LINE__)); 5865 KASSERT(pmc_ss_count == 0, 5866 ("[pmc,%d] Global SS count not empty", __LINE__)); 5867 5868 /* do processor and pmc-class dependent cleanup */ 5869 maxcpu = pmc_cpu_max(); 5870 5871 PMCDBG0(MOD,INI,3, "md cleanup"); 5872 if (md) { 5873 pmc_save_cpu_binding(&pb); 5874 for (cpu = 0; cpu < maxcpu; cpu++) { 5875 PMCDBG2(MOD,INI,1,"pmc-cleanup cpu=%d pcs=%p", 5876 cpu, pmc_pcpu[cpu]); 5877 if (!pmc_cpu_is_active(cpu) || pmc_pcpu[cpu] == NULL) 5878 continue; 5879 pmc_select_cpu(cpu); 5880 for (c = 0; c < md->pmd_nclass; c++) 5881 md->pmd_classdep[c].pcd_pcpu_fini(md, cpu); 5882 if (md->pmd_pcpu_fini) 5883 md->pmd_pcpu_fini(md, cpu); 5884 } 5885 5886 if (md->pmd_cputype == PMC_CPU_GENERIC) 5887 pmc_generic_cpu_finalize(md); 5888 else 5889 pmc_md_finalize(md); 5890 5891 pmc_mdep_free(md); 5892 md = NULL; 5893 pmc_restore_cpu_binding(&pb); 5894 } 5895 5896 /* Free per-cpu descriptors. */ 5897 for (cpu = 0; cpu < maxcpu; cpu++) { 5898 if (!pmc_cpu_is_active(cpu)) 5899 continue; 5900 KASSERT(pmc_pcpu[cpu]->pc_sb[PMC_HR] != NULL, 5901 ("[pmc,%d] Null hw cpu sample buffer cpu=%d", __LINE__, 5902 cpu)); 5903 KASSERT(pmc_pcpu[cpu]->pc_sb[PMC_SR] != NULL, 5904 ("[pmc,%d] Null sw cpu sample buffer cpu=%d", __LINE__, 5905 cpu)); 5906 KASSERT(pmc_pcpu[cpu]->pc_sb[PMC_UR] != NULL, 5907 ("[pmc,%d] Null userret cpu sample buffer cpu=%d", __LINE__, 5908 cpu)); 5909 free_domain(pmc_pcpu[cpu]->pc_sb[PMC_HR]->ps_callchains, M_PMC); 5910 free_domain(pmc_pcpu[cpu]->pc_sb[PMC_HR], M_PMC); 5911 free_domain(pmc_pcpu[cpu]->pc_sb[PMC_SR]->ps_callchains, M_PMC); 5912 free_domain(pmc_pcpu[cpu]->pc_sb[PMC_SR], M_PMC); 5913 free_domain(pmc_pcpu[cpu]->pc_sb[PMC_UR]->ps_callchains, M_PMC); 5914 free_domain(pmc_pcpu[cpu]->pc_sb[PMC_UR], M_PMC); 5915 free_domain(pmc_pcpu[cpu], M_PMC); 5916 } 5917 5918 free(pmc_pcpu, M_PMC); 5919 pmc_pcpu = NULL; 5920 5921 free(pmc_pcpu_saved, M_PMC); 5922 pmc_pcpu_saved = NULL; 5923 5924 if (pmc_pmcdisp) { 5925 free(pmc_pmcdisp, M_PMC); 5926 pmc_pmcdisp = NULL; 5927 } 5928 5929 if (pmc_rowindex_to_classdep) { 5930 free(pmc_rowindex_to_classdep, M_PMC); 5931 pmc_rowindex_to_classdep = NULL; 5932 } 5933 5934 pmclog_shutdown(); 5935 counter_u64_free(pmc_stats.pm_intr_ignored); 5936 counter_u64_free(pmc_stats.pm_intr_processed); 5937 counter_u64_free(pmc_stats.pm_intr_bufferfull); 5938 counter_u64_free(pmc_stats.pm_syscalls); 5939 counter_u64_free(pmc_stats.pm_syscall_errors); 5940 counter_u64_free(pmc_stats.pm_buffer_requests); 5941 counter_u64_free(pmc_stats.pm_buffer_requests_failed); 5942 counter_u64_free(pmc_stats.pm_log_sweeps); 5943 counter_u64_free(pmc_stats.pm_merges); 5944 counter_u64_free(pmc_stats.pm_overwrites); 5945 sx_xunlock(&pmc_sx); /* we are done */ 5946 } 5947 5948 /* 5949 * The function called at load/unload. 5950 */ 5951 5952 static int 5953 load (struct module *module __unused, int cmd, void *arg __unused) 5954 { 5955 int error; 5956 5957 error = 0; 5958 5959 switch (cmd) { 5960 case MOD_LOAD : 5961 /* initialize the subsystem */ 5962 error = pmc_initialize(); 5963 if (error != 0) 5964 break; 5965 PMCDBG2(MOD,INI,1, "syscall=%d maxcpu=%d", 5966 pmc_syscall_num, pmc_cpu_max()); 5967 break; 5968 5969 5970 case MOD_UNLOAD : 5971 case MOD_SHUTDOWN: 5972 pmc_cleanup(); 5973 PMCDBG0(MOD,INI,1, "unloaded"); 5974 break; 5975 5976 default : 5977 error = EINVAL; /* XXX should panic(9) */ 5978 break; 5979 } 5980 5981 return error; 5982 } 5983