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