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