fasttrap.c revision 211745
1179193Sjb/* 2179193Sjb * CDDL HEADER START 3179193Sjb * 4179193Sjb * The contents of this file are subject to the terms of the 5179193Sjb * Common Development and Distribution License (the "License"). 6179193Sjb * You may not use this file except in compliance with the License. 7179193Sjb * 8179193Sjb * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9179193Sjb * or http://www.opensolaris.org/os/licensing. 10179193Sjb * See the License for the specific language governing permissions 11179193Sjb * and limitations under the License. 12179193Sjb * 13179193Sjb * When distributing Covered Code, include this CDDL HEADER in each 14179193Sjb * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15179193Sjb * If applicable, add the following below this CDDL HEADER, with the 16179193Sjb * fields enclosed by brackets "[]" replaced with your own identifying 17179193Sjb * information: Portions Copyright [yyyy] [name of copyright owner] 18179193Sjb * 19179193Sjb * CDDL HEADER END 20211738Srpaulo * 21211738Srpaulo * Portions Copyright 2010 The FreeBSD Foundation 22211738Srpaulo * 23211738Srpaulo * $FreeBSD: head/sys/cddl/contrib/opensolaris/uts/common/dtrace/fasttrap.c 211745 2010-08-24 12:12:03Z rpaulo $ 24179193Sjb */ 25179193Sjb 26179193Sjb/* 27179198Sjb * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 28179193Sjb * Use is subject to license terms. 29179193Sjb */ 30179193Sjb 31211738Srpaulo#if defined(sun) 32179193Sjb#pragma ident "%Z%%M% %I% %E% SMI" 33211738Srpaulo#endif 34179193Sjb 35179193Sjb#include <sys/atomic.h> 36179193Sjb#include <sys/errno.h> 37179193Sjb#include <sys/stat.h> 38179193Sjb#include <sys/modctl.h> 39179193Sjb#include <sys/conf.h> 40179193Sjb#include <sys/systm.h> 41211738Srpaulo#if defined(sun) 42179193Sjb#include <sys/ddi.h> 43211738Srpaulo#endif 44179193Sjb#include <sys/sunddi.h> 45179193Sjb#include <sys/cpuvar.h> 46179193Sjb#include <sys/kmem.h> 47211738Srpaulo#if defined(sun) 48179193Sjb#include <sys/strsubr.h> 49211738Srpaulo#endif 50179193Sjb#include <sys/fasttrap.h> 51179193Sjb#include <sys/fasttrap_impl.h> 52179193Sjb#include <sys/fasttrap_isa.h> 53179193Sjb#include <sys/dtrace.h> 54179193Sjb#include <sys/dtrace_impl.h> 55179193Sjb#include <sys/sysmacros.h> 56179193Sjb#include <sys/proc.h> 57179193Sjb#include <sys/policy.h> 58211738Srpaulo#if defined(sun) 59179193Sjb#include <util/qsort.h> 60211738Srpaulo#endif 61211738Srpaulo#include <sys/mutex.h> 62211738Srpaulo#include <sys/kernel.h> 63211738Srpaulo#if !defined(sun) 64211738Srpaulo#include <sys/user.h> 65211738Srpaulo#include <sys/dtrace_bsd.h> 66211738Srpaulo#include <cddl/dev/dtrace/dtrace_cddl.h> 67211738Srpaulo#endif 68179193Sjb 69179193Sjb/* 70179193Sjb * User-Land Trap-Based Tracing 71179193Sjb * ---------------------------- 72179193Sjb * 73179193Sjb * The fasttrap provider allows DTrace consumers to instrument any user-level 74179193Sjb * instruction to gather data; this includes probes with semantic 75179193Sjb * signifigance like entry and return as well as simple offsets into the 76179193Sjb * function. While the specific techniques used are very ISA specific, the 77179193Sjb * methodology is generalizable to any architecture. 78179193Sjb * 79179193Sjb * 80179193Sjb * The General Methodology 81179193Sjb * ----------------------- 82179193Sjb * 83179193Sjb * With the primary goal of tracing every user-land instruction and the 84179193Sjb * limitation that we can't trust user space so don't want to rely on much 85179193Sjb * information there, we begin by replacing the instructions we want to trace 86179193Sjb * with trap instructions. Each instruction we overwrite is saved into a hash 87179193Sjb * table keyed by process ID and pc address. When we enter the kernel due to 88179193Sjb * this trap instruction, we need the effects of the replaced instruction to 89179193Sjb * appear to have occurred before we proceed with the user thread's 90179193Sjb * execution. 91179193Sjb * 92179193Sjb * Each user level thread is represented by a ulwp_t structure which is 93179193Sjb * always easily accessible through a register. The most basic way to produce 94179193Sjb * the effects of the instruction we replaced is to copy that instruction out 95179193Sjb * to a bit of scratch space reserved in the user thread's ulwp_t structure 96179193Sjb * (a sort of kernel-private thread local storage), set the PC to that 97179193Sjb * scratch space and single step. When we reenter the kernel after single 98179193Sjb * stepping the instruction we must then adjust the PC to point to what would 99179193Sjb * normally be the next instruction. Of course, special care must be taken 100179193Sjb * for branches and jumps, but these represent such a small fraction of any 101179193Sjb * instruction set that writing the code to emulate these in the kernel is 102179193Sjb * not too difficult. 103179193Sjb * 104179193Sjb * Return probes may require several tracepoints to trace every return site, 105179193Sjb * and, conversely, each tracepoint may activate several probes (the entry 106179193Sjb * and offset 0 probes, for example). To solve this muliplexing problem, 107179193Sjb * tracepoints contain lists of probes to activate and probes contain lists 108179193Sjb * of tracepoints to enable. If a probe is activated, it adds its ID to 109179193Sjb * existing tracepoints or creates new ones as necessary. 110179193Sjb * 111179193Sjb * Most probes are activated _before_ the instruction is executed, but return 112179193Sjb * probes are activated _after_ the effects of the last instruction of the 113179193Sjb * function are visible. Return probes must be fired _after_ we have 114179193Sjb * single-stepped the instruction whereas all other probes are fired 115179193Sjb * beforehand. 116179193Sjb * 117179193Sjb * 118179193Sjb * Lock Ordering 119179193Sjb * ------------- 120179193Sjb * 121179193Sjb * The lock ordering below -- both internally and with respect to the DTrace 122179193Sjb * framework -- is a little tricky and bears some explanation. Each provider 123179193Sjb * has a lock (ftp_mtx) that protects its members including reference counts 124179193Sjb * for enabled probes (ftp_rcount), consumers actively creating probes 125179193Sjb * (ftp_ccount) and USDT consumers (ftp_mcount); all three prevent a provider 126179193Sjb * from being freed. A provider is looked up by taking the bucket lock for the 127179193Sjb * provider hash table, and is returned with its lock held. The provider lock 128179193Sjb * may be taken in functions invoked by the DTrace framework, but may not be 129179193Sjb * held while calling functions in the DTrace framework. 130179193Sjb * 131179193Sjb * To ensure consistency over multiple calls to the DTrace framework, the 132179193Sjb * creation lock (ftp_cmtx) should be held. Naturally, the creation lock may 133179193Sjb * not be taken when holding the provider lock as that would create a cyclic 134179193Sjb * lock ordering. In situations where one would naturally take the provider 135179193Sjb * lock and then the creation lock, we instead up a reference count to prevent 136179193Sjb * the provider from disappearing, drop the provider lock, and acquire the 137179193Sjb * creation lock. 138179193Sjb * 139179193Sjb * Briefly: 140179193Sjb * bucket lock before provider lock 141179193Sjb * DTrace before provider lock 142179193Sjb * creation lock before DTrace 143179193Sjb * never hold the provider lock and creation lock simultaneously 144179193Sjb */ 145179193Sjb 146211738Srpaulostatic d_open_t fasttrap_open; 147211738Srpaulostatic d_ioctl_t fasttrap_ioctl; 148211738Srpaulo 149211738Srpaulostatic struct cdevsw fasttrap_cdevsw = { 150211738Srpaulo .d_version = D_VERSION, 151211738Srpaulo .d_open = fasttrap_open, 152211738Srpaulo .d_ioctl = fasttrap_ioctl, 153211738Srpaulo .d_name = "fasttrap", 154211738Srpaulo}; 155211738Srpaulostatic struct cdev *fasttrap_cdev; 156179193Sjbstatic dtrace_meta_provider_id_t fasttrap_meta_id; 157179193Sjb 158211738Srpaulostatic struct callout fasttrap_timeout; 159211738Srpaulostatic struct mtx fasttrap_cleanup_mtx; 160179193Sjbstatic uint_t fasttrap_cleanup_work; 161179193Sjb 162179193Sjb/* 163179193Sjb * Generation count on modifications to the global tracepoint lookup table. 164179193Sjb */ 165179193Sjbstatic volatile uint64_t fasttrap_mod_gen; 166179193Sjb 167179193Sjb/* 168179193Sjb * When the fasttrap provider is loaded, fasttrap_max is set to either 169179193Sjb * FASTTRAP_MAX_DEFAULT or the value for fasttrap-max-probes in the 170179193Sjb * fasttrap.conf file. Each time a probe is created, fasttrap_total is 171179193Sjb * incremented by the number of tracepoints that may be associated with that 172179193Sjb * probe; fasttrap_total is capped at fasttrap_max. 173179193Sjb */ 174179193Sjb#define FASTTRAP_MAX_DEFAULT 250000 175179193Sjbstatic uint32_t fasttrap_max; 176179193Sjbstatic uint32_t fasttrap_total; 177179193Sjb 178179193Sjb 179179193Sjb#define FASTTRAP_TPOINTS_DEFAULT_SIZE 0x4000 180179193Sjb#define FASTTRAP_PROVIDERS_DEFAULT_SIZE 0x100 181179193Sjb#define FASTTRAP_PROCS_DEFAULT_SIZE 0x100 182179193Sjb 183179193Sjb#define FASTTRAP_PID_NAME "pid" 184179193Sjb 185179193Sjbfasttrap_hash_t fasttrap_tpoints; 186179193Sjbstatic fasttrap_hash_t fasttrap_provs; 187179193Sjbstatic fasttrap_hash_t fasttrap_procs; 188179193Sjb 189179193Sjbstatic uint64_t fasttrap_pid_count; /* pid ref count */ 190179193Sjbstatic kmutex_t fasttrap_count_mtx; /* lock on ref count */ 191179193Sjb 192179193Sjb#define FASTTRAP_ENABLE_FAIL 1 193179193Sjb#define FASTTRAP_ENABLE_PARTIAL 2 194179193Sjb 195179193Sjbstatic int fasttrap_tracepoint_enable(proc_t *, fasttrap_probe_t *, uint_t); 196179193Sjbstatic void fasttrap_tracepoint_disable(proc_t *, fasttrap_probe_t *, uint_t); 197179193Sjb 198179193Sjbstatic fasttrap_provider_t *fasttrap_provider_lookup(pid_t, const char *, 199179193Sjb const dtrace_pattr_t *); 200179193Sjbstatic void fasttrap_provider_retire(pid_t, const char *, int); 201179193Sjbstatic void fasttrap_provider_free(fasttrap_provider_t *); 202179193Sjb 203179193Sjbstatic fasttrap_proc_t *fasttrap_proc_lookup(pid_t); 204179193Sjbstatic void fasttrap_proc_release(fasttrap_proc_t *); 205179193Sjb 206179193Sjb#define FASTTRAP_PROVS_INDEX(pid, name) \ 207179193Sjb ((fasttrap_hash_str(name) + (pid)) & fasttrap_provs.fth_mask) 208179193Sjb 209179193Sjb#define FASTTRAP_PROCS_INDEX(pid) ((pid) & fasttrap_procs.fth_mask) 210179193Sjb 211179193Sjbstatic int 212179193Sjbfasttrap_highbit(ulong_t i) 213179193Sjb{ 214179193Sjb int h = 1; 215179193Sjb 216179193Sjb if (i == 0) 217179193Sjb return (0); 218179193Sjb#ifdef _LP64 219179193Sjb if (i & 0xffffffff00000000ul) { 220179193Sjb h += 32; i >>= 32; 221179193Sjb } 222179193Sjb#endif 223179193Sjb if (i & 0xffff0000) { 224179193Sjb h += 16; i >>= 16; 225179193Sjb } 226179193Sjb if (i & 0xff00) { 227179193Sjb h += 8; i >>= 8; 228179193Sjb } 229179193Sjb if (i & 0xf0) { 230179193Sjb h += 4; i >>= 4; 231179193Sjb } 232179193Sjb if (i & 0xc) { 233179193Sjb h += 2; i >>= 2; 234179193Sjb } 235179193Sjb if (i & 0x2) { 236179193Sjb h += 1; 237179193Sjb } 238179193Sjb return (h); 239179193Sjb} 240179193Sjb 241179193Sjbstatic uint_t 242179193Sjbfasttrap_hash_str(const char *p) 243179193Sjb{ 244179193Sjb unsigned int g; 245179193Sjb uint_t hval = 0; 246179193Sjb 247179193Sjb while (*p) { 248179193Sjb hval = (hval << 4) + *p++; 249179193Sjb if ((g = (hval & 0xf0000000)) != 0) 250179193Sjb hval ^= g >> 24; 251179193Sjb hval &= ~g; 252179193Sjb } 253179193Sjb return (hval); 254179193Sjb} 255179193Sjb 256179193Sjbvoid 257179193Sjbfasttrap_sigtrap(proc_t *p, kthread_t *t, uintptr_t pc) 258179193Sjb{ 259211738Srpaulo#if defined(sun) 260179193Sjb sigqueue_t *sqp = kmem_zalloc(sizeof (sigqueue_t), KM_SLEEP); 261179193Sjb 262179193Sjb sqp->sq_info.si_signo = SIGTRAP; 263179193Sjb sqp->sq_info.si_code = TRAP_DTRACE; 264179193Sjb sqp->sq_info.si_addr = (caddr_t)pc; 265179193Sjb 266179193Sjb mutex_enter(&p->p_lock); 267179193Sjb sigaddqa(p, t, sqp); 268179193Sjb mutex_exit(&p->p_lock); 269179193Sjb 270179193Sjb if (t != NULL) 271179193Sjb aston(t); 272211738Srpaulo#else 273211738Srpaulo ksiginfo_t *ksi = kmem_zalloc(sizeof (ksiginfo_t), KM_SLEEP); 274211738Srpaulo 275211738Srpaulo ksiginfo_init(ksi); 276211738Srpaulo ksi->ksi_signo = SIGTRAP; 277211738Srpaulo ksi->ksi_code = TRAP_DTRACE; 278211738Srpaulo ksi->ksi_addr = (caddr_t)pc; 279211738Srpaulo PROC_LOCK(p); 280211745Srpaulo (void) tdksignal(t, SIGTRAP, ksi); 281211738Srpaulo PROC_UNLOCK(p); 282211738Srpaulo#endif 283179193Sjb} 284179193Sjb 285179193Sjb/* 286179193Sjb * This function ensures that no threads are actively using the memory 287179193Sjb * associated with probes that were formerly live. 288179193Sjb */ 289179193Sjbstatic void 290179193Sjbfasttrap_mod_barrier(uint64_t gen) 291179193Sjb{ 292211738Srpaulo#if defined(sun) 293179193Sjb int i; 294211738Srpaulo#endif 295179193Sjb 296179193Sjb if (gen < fasttrap_mod_gen) 297179193Sjb return; 298179193Sjb 299179193Sjb fasttrap_mod_gen++; 300179193Sjb 301211738Srpaulo#if defined(sun) 302179193Sjb for (i = 0; i < NCPU; i++) { 303179193Sjb mutex_enter(&cpu_core[i].cpuc_pid_lock); 304179193Sjb mutex_exit(&cpu_core[i].cpuc_pid_lock); 305179193Sjb } 306211738Srpaulo#else 307211738Srpaulo /* XXX */ 308211738Srpaulo __asm __volatile("": : :"memory"); 309211738Srpaulo#endif 310179193Sjb} 311179193Sjb 312179193Sjb/* 313179193Sjb * This is the timeout's callback for cleaning up the providers and their 314179193Sjb * probes. 315179193Sjb */ 316179193Sjb/*ARGSUSED*/ 317179193Sjbstatic void 318179193Sjbfasttrap_pid_cleanup_cb(void *data) 319179193Sjb{ 320179193Sjb fasttrap_provider_t **fpp, *fp; 321179193Sjb fasttrap_bucket_t *bucket; 322179193Sjb dtrace_provider_id_t provid; 323211738Srpaulo int i, later = 0; 324179193Sjb 325179193Sjb static volatile int in = 0; 326179193Sjb ASSERT(in == 0); 327179193Sjb in = 1; 328179193Sjb 329179193Sjb while (fasttrap_cleanup_work) { 330179193Sjb fasttrap_cleanup_work = 0; 331211738Srpaulo mtx_unlock(&fasttrap_cleanup_mtx); 332179193Sjb 333179193Sjb later = 0; 334179193Sjb 335179193Sjb /* 336179193Sjb * Iterate over all the providers trying to remove the marked 337179193Sjb * ones. If a provider is marked but not retired, we just 338179193Sjb * have to take a crack at removing it -- it's no big deal if 339179193Sjb * we can't. 340179193Sjb */ 341179193Sjb for (i = 0; i < fasttrap_provs.fth_nent; i++) { 342179193Sjb bucket = &fasttrap_provs.fth_table[i]; 343179193Sjb mutex_enter(&bucket->ftb_mtx); 344179193Sjb fpp = (fasttrap_provider_t **)&bucket->ftb_data; 345179193Sjb 346179193Sjb while ((fp = *fpp) != NULL) { 347179193Sjb if (!fp->ftp_marked) { 348179193Sjb fpp = &fp->ftp_next; 349179193Sjb continue; 350179193Sjb } 351179193Sjb 352179193Sjb mutex_enter(&fp->ftp_mtx); 353179193Sjb 354179193Sjb /* 355179193Sjb * If this provider has consumers actively 356179193Sjb * creating probes (ftp_ccount) or is a USDT 357179193Sjb * provider (ftp_mcount), we can't unregister 358179193Sjb * or even condense. 359179193Sjb */ 360179193Sjb if (fp->ftp_ccount != 0 || 361179193Sjb fp->ftp_mcount != 0) { 362179193Sjb mutex_exit(&fp->ftp_mtx); 363179193Sjb fp->ftp_marked = 0; 364179193Sjb continue; 365179193Sjb } 366179193Sjb 367179193Sjb if (!fp->ftp_retired || fp->ftp_rcount != 0) 368179193Sjb fp->ftp_marked = 0; 369179193Sjb 370179193Sjb mutex_exit(&fp->ftp_mtx); 371179193Sjb 372179193Sjb /* 373179193Sjb * If we successfully unregister this 374179193Sjb * provider we can remove it from the hash 375179193Sjb * chain and free the memory. If our attempt 376179193Sjb * to unregister fails and this is a retired 377179193Sjb * provider, increment our flag to try again 378179193Sjb * pretty soon. If we've consumed more than 379179193Sjb * half of our total permitted number of 380179193Sjb * probes call dtrace_condense() to try to 381179193Sjb * clean out the unenabled probes. 382179193Sjb */ 383179193Sjb provid = fp->ftp_provid; 384179193Sjb if (dtrace_unregister(provid) != 0) { 385179193Sjb if (fasttrap_total > fasttrap_max / 2) 386179193Sjb (void) dtrace_condense(provid); 387179193Sjb later += fp->ftp_marked; 388179193Sjb fpp = &fp->ftp_next; 389179193Sjb } else { 390179193Sjb *fpp = fp->ftp_next; 391179193Sjb fasttrap_provider_free(fp); 392179193Sjb } 393179193Sjb } 394179193Sjb mutex_exit(&bucket->ftb_mtx); 395179193Sjb } 396179193Sjb 397211738Srpaulo mtx_lock(&fasttrap_cleanup_mtx); 398179193Sjb } 399179193Sjb 400211738Srpaulo#if 0 401179193Sjb ASSERT(fasttrap_timeout != 0); 402211738Srpaulo#endif 403179193Sjb 404179193Sjb /* 405179193Sjb * If we were unable to remove a retired provider, try again after 406179193Sjb * a second. This situation can occur in certain circumstances where 407179193Sjb * providers cannot be unregistered even though they have no probes 408179193Sjb * enabled because of an execution of dtrace -l or something similar. 409179193Sjb * If the timeout has been disabled (set to 1 because we're trying 410179193Sjb * to detach), we set fasttrap_cleanup_work to ensure that we'll 411179193Sjb * get a chance to do that work if and when the timeout is reenabled 412179193Sjb * (if detach fails). 413179193Sjb */ 414211738Srpaulo if (later > 0 && callout_active(&fasttrap_timeout)) 415211738Srpaulo callout_reset(&fasttrap_timeout, hz, &fasttrap_pid_cleanup_cb, 416211738Srpaulo NULL); 417179193Sjb else if (later > 0) 418179193Sjb fasttrap_cleanup_work = 1; 419211738Srpaulo else { 420211738Srpaulo#if !defined(sun) 421211738Srpaulo /* Nothing to be done for FreeBSD */ 422211738Srpaulo#endif 423211738Srpaulo } 424179193Sjb 425179193Sjb in = 0; 426179193Sjb} 427179193Sjb 428179193Sjb/* 429179193Sjb * Activates the asynchronous cleanup mechanism. 430179193Sjb */ 431179193Sjbstatic void 432179193Sjbfasttrap_pid_cleanup(void) 433179193Sjb{ 434211738Srpaulo 435211738Srpaulo mtx_lock(&fasttrap_cleanup_mtx); 436179193Sjb fasttrap_cleanup_work = 1; 437211738Srpaulo callout_reset(&fasttrap_timeout, 1, &fasttrap_pid_cleanup_cb, NULL); 438211738Srpaulo mtx_unlock(&fasttrap_cleanup_mtx); 439179193Sjb} 440179193Sjb 441179193Sjb/* 442179193Sjb * This is called from cfork() via dtrace_fasttrap_fork(). The child 443179198Sjb * process's address space is (roughly) a copy of the parent process's so 444179193Sjb * we have to remove all the instrumentation we had previously enabled in the 445179193Sjb * parent. 446179193Sjb */ 447179193Sjbstatic void 448179193Sjbfasttrap_fork(proc_t *p, proc_t *cp) 449179193Sjb{ 450179193Sjb pid_t ppid = p->p_pid; 451179193Sjb int i; 452179193Sjb 453211738Srpaulo#if defined(sun) 454179193Sjb ASSERT(curproc == p); 455179193Sjb ASSERT(p->p_proc_flag & P_PR_LOCK); 456211738Srpaulo#else 457211738Srpaulo PROC_LOCK_ASSERT(p, MA_OWNED); 458211738Srpaulo#endif 459211738Srpaulo#if defined(sun) 460179193Sjb ASSERT(p->p_dtrace_count > 0); 461211738Srpaulo#else 462211738Srpaulo /* 463211738Srpaulo * This check is purposely here instead of in kern_fork.c because, 464211738Srpaulo * for legal resons, we cannot include the dtrace_cddl.h header 465211738Srpaulo * inside kern_fork.c and insert if-clause there. 466211738Srpaulo */ 467211738Srpaulo if (p->p_dtrace_count == 0) 468211738Srpaulo return; 469211738Srpaulo#endif 470179193Sjb ASSERT(cp->p_dtrace_count == 0); 471179193Sjb 472179193Sjb /* 473179193Sjb * This would be simpler and faster if we maintained per-process 474179193Sjb * hash tables of enabled tracepoints. It could, however, potentially 475179193Sjb * slow down execution of a tracepoint since we'd need to go 476179193Sjb * through two levels of indirection. In the future, we should 477179193Sjb * consider either maintaining per-process ancillary lists of 478179193Sjb * enabled tracepoints or hanging a pointer to a per-process hash 479179193Sjb * table of enabled tracepoints off the proc structure. 480179193Sjb */ 481179193Sjb 482179193Sjb /* 483179193Sjb * We don't have to worry about the child process disappearing 484179193Sjb * because we're in fork(). 485179193Sjb */ 486211738Srpaulo#if defined(sun) 487211738Srpaulo mtx_lock_spin(&cp->p_slock); 488179193Sjb sprlock_proc(cp); 489211738Srpaulo mtx_unlock_spin(&cp->p_slock); 490211738Srpaulo#endif 491179193Sjb 492179193Sjb /* 493179193Sjb * Iterate over every tracepoint looking for ones that belong to the 494179193Sjb * parent process, and remove each from the child process. 495179193Sjb */ 496179193Sjb for (i = 0; i < fasttrap_tpoints.fth_nent; i++) { 497179193Sjb fasttrap_tracepoint_t *tp; 498179193Sjb fasttrap_bucket_t *bucket = &fasttrap_tpoints.fth_table[i]; 499179193Sjb 500179193Sjb mutex_enter(&bucket->ftb_mtx); 501179193Sjb for (tp = bucket->ftb_data; tp != NULL; tp = tp->ftt_next) { 502179193Sjb if (tp->ftt_pid == ppid && 503179193Sjb tp->ftt_proc->ftpc_acount != 0) { 504179193Sjb int ret = fasttrap_tracepoint_remove(cp, tp); 505179193Sjb ASSERT(ret == 0); 506179198Sjb 507179198Sjb /* 508179198Sjb * The count of active providers can only be 509179198Sjb * decremented (i.e. to zero) during exec, 510179198Sjb * exit, and removal of a meta provider so it 511179198Sjb * should be impossible to drop the count 512179198Sjb * mid-fork. 513179198Sjb */ 514179198Sjb ASSERT(tp->ftt_proc->ftpc_acount != 0); 515179193Sjb } 516179193Sjb } 517179193Sjb mutex_exit(&bucket->ftb_mtx); 518179193Sjb } 519179193Sjb 520211738Srpaulo#if defined(sun) 521179193Sjb mutex_enter(&cp->p_lock); 522179193Sjb sprunlock(cp); 523211738Srpaulo#endif 524179193Sjb} 525179193Sjb 526179193Sjb/* 527179193Sjb * This is called from proc_exit() or from exec_common() if p_dtrace_probes 528179193Sjb * is set on the proc structure to indicate that there is a pid provider 529179193Sjb * associated with this process. 530179193Sjb */ 531179193Sjbstatic void 532179193Sjbfasttrap_exec_exit(proc_t *p) 533179193Sjb{ 534211738Srpaulo#if defined(sun) 535179193Sjb ASSERT(p == curproc); 536211738Srpaulo#endif 537211738Srpaulo PROC_LOCK_ASSERT(p, MA_OWNED); 538211738Srpaulo PROC_UNLOCK(p); 539179193Sjb 540179193Sjb /* 541179193Sjb * We clean up the pid provider for this process here; user-land 542179193Sjb * static probes are handled by the meta-provider remove entry point. 543179193Sjb */ 544179193Sjb fasttrap_provider_retire(p->p_pid, FASTTRAP_PID_NAME, 0); 545211738Srpaulo PROC_LOCK(p); 546179193Sjb} 547179193Sjb 548179193Sjb 549179193Sjb/*ARGSUSED*/ 550179193Sjbstatic void 551211738Srpaulofasttrap_pid_provide(void *arg, dtrace_probedesc_t *desc) 552179193Sjb{ 553179193Sjb /* 554179193Sjb * There are no "default" pid probes. 555179193Sjb */ 556179193Sjb} 557179193Sjb 558179193Sjbstatic int 559179193Sjbfasttrap_tracepoint_enable(proc_t *p, fasttrap_probe_t *probe, uint_t index) 560179193Sjb{ 561179193Sjb fasttrap_tracepoint_t *tp, *new_tp = NULL; 562179193Sjb fasttrap_bucket_t *bucket; 563179193Sjb fasttrap_id_t *id; 564179193Sjb pid_t pid; 565179193Sjb uintptr_t pc; 566179193Sjb 567179193Sjb ASSERT(index < probe->ftp_ntps); 568179193Sjb 569179193Sjb pid = probe->ftp_pid; 570179193Sjb pc = probe->ftp_tps[index].fit_tp->ftt_pc; 571179193Sjb id = &probe->ftp_tps[index].fit_id; 572179193Sjb 573179193Sjb ASSERT(probe->ftp_tps[index].fit_tp->ftt_pid == pid); 574179193Sjb 575211738Srpaulo#if defined(sun) 576179193Sjb ASSERT(!(p->p_flag & SVFORK)); 577211738Srpaulo#endif 578179193Sjb 579179193Sjb /* 580179193Sjb * Before we make any modifications, make sure we've imposed a barrier 581179193Sjb * on the generation in which this probe was last modified. 582179193Sjb */ 583179193Sjb fasttrap_mod_barrier(probe->ftp_gen); 584179193Sjb 585179193Sjb bucket = &fasttrap_tpoints.fth_table[FASTTRAP_TPOINTS_INDEX(pid, pc)]; 586179193Sjb 587179193Sjb /* 588179193Sjb * If the tracepoint has already been enabled, just add our id to the 589179193Sjb * list of interested probes. This may be our second time through 590179193Sjb * this path in which case we'll have constructed the tracepoint we'd 591179193Sjb * like to install. If we can't find a match, and have an allocated 592179193Sjb * tracepoint ready to go, enable that one now. 593179193Sjb * 594179193Sjb * A tracepoint whose process is defunct is also considered defunct. 595179193Sjb */ 596179193Sjbagain: 597179193Sjb mutex_enter(&bucket->ftb_mtx); 598179193Sjb for (tp = bucket->ftb_data; tp != NULL; tp = tp->ftt_next) { 599179198Sjb /* 600179198Sjb * Note that it's safe to access the active count on the 601179198Sjb * associated proc structure because we know that at least one 602179198Sjb * provider (this one) will still be around throughout this 603179198Sjb * operation. 604179198Sjb */ 605179193Sjb if (tp->ftt_pid != pid || tp->ftt_pc != pc || 606179193Sjb tp->ftt_proc->ftpc_acount == 0) 607179193Sjb continue; 608179193Sjb 609179193Sjb /* 610179193Sjb * Now that we've found a matching tracepoint, it would be 611179193Sjb * a decent idea to confirm that the tracepoint is still 612179193Sjb * enabled and the trap instruction hasn't been overwritten. 613179193Sjb * Since this is a little hairy, we'll punt for now. 614179193Sjb */ 615179193Sjb 616179193Sjb /* 617179193Sjb * This can't be the first interested probe. We don't have 618179193Sjb * to worry about another thread being in the midst of 619179193Sjb * deleting this tracepoint (which would be the only valid 620179193Sjb * reason for a tracepoint to have no interested probes) 621179193Sjb * since we're holding P_PR_LOCK for this process. 622179193Sjb */ 623179193Sjb ASSERT(tp->ftt_ids != NULL || tp->ftt_retids != NULL); 624179193Sjb 625179193Sjb switch (id->fti_ptype) { 626179193Sjb case DTFTP_ENTRY: 627179193Sjb case DTFTP_OFFSETS: 628179193Sjb case DTFTP_IS_ENABLED: 629179193Sjb id->fti_next = tp->ftt_ids; 630179193Sjb membar_producer(); 631179193Sjb tp->ftt_ids = id; 632179193Sjb membar_producer(); 633179193Sjb break; 634179193Sjb 635179193Sjb case DTFTP_RETURN: 636179193Sjb case DTFTP_POST_OFFSETS: 637179193Sjb id->fti_next = tp->ftt_retids; 638179193Sjb membar_producer(); 639179193Sjb tp->ftt_retids = id; 640179193Sjb membar_producer(); 641179193Sjb break; 642179193Sjb 643179193Sjb default: 644179193Sjb ASSERT(0); 645179193Sjb } 646179193Sjb 647179193Sjb mutex_exit(&bucket->ftb_mtx); 648179193Sjb 649179193Sjb if (new_tp != NULL) { 650179193Sjb new_tp->ftt_ids = NULL; 651179193Sjb new_tp->ftt_retids = NULL; 652179193Sjb } 653179193Sjb 654179193Sjb return (0); 655179193Sjb } 656179193Sjb 657179193Sjb /* 658179193Sjb * If we have a good tracepoint ready to go, install it now while 659179193Sjb * we have the lock held and no one can screw with us. 660179193Sjb */ 661179193Sjb if (new_tp != NULL) { 662179193Sjb int rc = 0; 663179193Sjb 664179193Sjb new_tp->ftt_next = bucket->ftb_data; 665179193Sjb membar_producer(); 666179193Sjb bucket->ftb_data = new_tp; 667179193Sjb membar_producer(); 668179193Sjb mutex_exit(&bucket->ftb_mtx); 669179193Sjb 670179193Sjb /* 671179193Sjb * Activate the tracepoint in the ISA-specific manner. 672179193Sjb * If this fails, we need to report the failure, but 673179193Sjb * indicate that this tracepoint must still be disabled 674179193Sjb * by calling fasttrap_tracepoint_disable(). 675179193Sjb */ 676179193Sjb if (fasttrap_tracepoint_install(p, new_tp) != 0) 677179193Sjb rc = FASTTRAP_ENABLE_PARTIAL; 678179193Sjb 679179193Sjb /* 680179193Sjb * Increment the count of the number of tracepoints active in 681179193Sjb * the victim process. 682179193Sjb */ 683211738Srpaulo#if defined(sun) 684179193Sjb ASSERT(p->p_proc_flag & P_PR_LOCK); 685211738Srpaulo#else 686211738Srpaulo PROC_LOCK_ASSERT(p, MA_OWNED); 687211738Srpaulo#endif 688179193Sjb p->p_dtrace_count++; 689179193Sjb 690179193Sjb return (rc); 691179193Sjb } 692179193Sjb 693179193Sjb mutex_exit(&bucket->ftb_mtx); 694179193Sjb 695179193Sjb /* 696179193Sjb * Initialize the tracepoint that's been preallocated with the probe. 697179193Sjb */ 698179193Sjb new_tp = probe->ftp_tps[index].fit_tp; 699179193Sjb 700179193Sjb ASSERT(new_tp->ftt_pid == pid); 701179193Sjb ASSERT(new_tp->ftt_pc == pc); 702179193Sjb ASSERT(new_tp->ftt_proc == probe->ftp_prov->ftp_proc); 703179193Sjb ASSERT(new_tp->ftt_ids == NULL); 704179193Sjb ASSERT(new_tp->ftt_retids == NULL); 705179193Sjb 706179193Sjb switch (id->fti_ptype) { 707179193Sjb case DTFTP_ENTRY: 708179193Sjb case DTFTP_OFFSETS: 709179193Sjb case DTFTP_IS_ENABLED: 710179193Sjb id->fti_next = NULL; 711179193Sjb new_tp->ftt_ids = id; 712179193Sjb break; 713179193Sjb 714179193Sjb case DTFTP_RETURN: 715179193Sjb case DTFTP_POST_OFFSETS: 716179193Sjb id->fti_next = NULL; 717179193Sjb new_tp->ftt_retids = id; 718179193Sjb break; 719179193Sjb 720179193Sjb default: 721179193Sjb ASSERT(0); 722179193Sjb } 723179193Sjb 724179193Sjb /* 725179193Sjb * If the ISA-dependent initialization goes to plan, go back to the 726179193Sjb * beginning and try to install this freshly made tracepoint. 727179193Sjb */ 728179193Sjb if (fasttrap_tracepoint_init(p, new_tp, pc, id->fti_ptype) == 0) 729179193Sjb goto again; 730179193Sjb 731179193Sjb new_tp->ftt_ids = NULL; 732179193Sjb new_tp->ftt_retids = NULL; 733179193Sjb 734179193Sjb return (FASTTRAP_ENABLE_FAIL); 735179193Sjb} 736179193Sjb 737179193Sjbstatic void 738179193Sjbfasttrap_tracepoint_disable(proc_t *p, fasttrap_probe_t *probe, uint_t index) 739179193Sjb{ 740179193Sjb fasttrap_bucket_t *bucket; 741179193Sjb fasttrap_provider_t *provider = probe->ftp_prov; 742179193Sjb fasttrap_tracepoint_t **pp, *tp; 743211738Srpaulo fasttrap_id_t *id, **idp = NULL; 744179193Sjb pid_t pid; 745179193Sjb uintptr_t pc; 746179193Sjb 747179193Sjb ASSERT(index < probe->ftp_ntps); 748179193Sjb 749179193Sjb pid = probe->ftp_pid; 750179193Sjb pc = probe->ftp_tps[index].fit_tp->ftt_pc; 751179193Sjb id = &probe->ftp_tps[index].fit_id; 752179193Sjb 753179193Sjb ASSERT(probe->ftp_tps[index].fit_tp->ftt_pid == pid); 754179193Sjb 755179193Sjb /* 756179193Sjb * Find the tracepoint and make sure that our id is one of the 757179193Sjb * ones registered with it. 758179193Sjb */ 759179193Sjb bucket = &fasttrap_tpoints.fth_table[FASTTRAP_TPOINTS_INDEX(pid, pc)]; 760179193Sjb mutex_enter(&bucket->ftb_mtx); 761179193Sjb for (tp = bucket->ftb_data; tp != NULL; tp = tp->ftt_next) { 762179193Sjb if (tp->ftt_pid == pid && tp->ftt_pc == pc && 763179193Sjb tp->ftt_proc == provider->ftp_proc) 764179193Sjb break; 765179193Sjb } 766179193Sjb 767179193Sjb /* 768179193Sjb * If we somehow lost this tracepoint, we're in a world of hurt. 769179193Sjb */ 770179193Sjb ASSERT(tp != NULL); 771179193Sjb 772179193Sjb switch (id->fti_ptype) { 773179193Sjb case DTFTP_ENTRY: 774179193Sjb case DTFTP_OFFSETS: 775179193Sjb case DTFTP_IS_ENABLED: 776179193Sjb ASSERT(tp->ftt_ids != NULL); 777179193Sjb idp = &tp->ftt_ids; 778179193Sjb break; 779179193Sjb 780179193Sjb case DTFTP_RETURN: 781179193Sjb case DTFTP_POST_OFFSETS: 782179193Sjb ASSERT(tp->ftt_retids != NULL); 783179193Sjb idp = &tp->ftt_retids; 784179193Sjb break; 785179193Sjb 786179193Sjb default: 787179193Sjb ASSERT(0); 788179193Sjb } 789179193Sjb 790179193Sjb while ((*idp)->fti_probe != probe) { 791179193Sjb idp = &(*idp)->fti_next; 792179193Sjb ASSERT(*idp != NULL); 793179193Sjb } 794179193Sjb 795179193Sjb id = *idp; 796179193Sjb *idp = id->fti_next; 797179193Sjb membar_producer(); 798179193Sjb 799179193Sjb ASSERT(id->fti_probe == probe); 800179193Sjb 801179193Sjb /* 802179193Sjb * If there are other registered enablings of this tracepoint, we're 803179193Sjb * all done, but if this was the last probe assocated with this 804179193Sjb * this tracepoint, we need to remove and free it. 805179193Sjb */ 806179193Sjb if (tp->ftt_ids != NULL || tp->ftt_retids != NULL) { 807179193Sjb 808179193Sjb /* 809179193Sjb * If the current probe's tracepoint is in use, swap it 810179193Sjb * for an unused tracepoint. 811179193Sjb */ 812179193Sjb if (tp == probe->ftp_tps[index].fit_tp) { 813179193Sjb fasttrap_probe_t *tmp_probe; 814179193Sjb fasttrap_tracepoint_t **tmp_tp; 815179193Sjb uint_t tmp_index; 816179193Sjb 817179193Sjb if (tp->ftt_ids != NULL) { 818179193Sjb tmp_probe = tp->ftt_ids->fti_probe; 819179193Sjb /* LINTED - alignment */ 820179193Sjb tmp_index = FASTTRAP_ID_INDEX(tp->ftt_ids); 821179193Sjb tmp_tp = &tmp_probe->ftp_tps[tmp_index].fit_tp; 822179193Sjb } else { 823179193Sjb tmp_probe = tp->ftt_retids->fti_probe; 824179193Sjb /* LINTED - alignment */ 825179193Sjb tmp_index = FASTTRAP_ID_INDEX(tp->ftt_retids); 826179193Sjb tmp_tp = &tmp_probe->ftp_tps[tmp_index].fit_tp; 827179193Sjb } 828179193Sjb 829179193Sjb ASSERT(*tmp_tp != NULL); 830179193Sjb ASSERT(*tmp_tp != probe->ftp_tps[index].fit_tp); 831179193Sjb ASSERT((*tmp_tp)->ftt_ids == NULL); 832179193Sjb ASSERT((*tmp_tp)->ftt_retids == NULL); 833179193Sjb 834179193Sjb probe->ftp_tps[index].fit_tp = *tmp_tp; 835179193Sjb *tmp_tp = tp; 836179193Sjb } 837179193Sjb 838179193Sjb mutex_exit(&bucket->ftb_mtx); 839179193Sjb 840179193Sjb /* 841179193Sjb * Tag the modified probe with the generation in which it was 842179193Sjb * changed. 843179193Sjb */ 844179193Sjb probe->ftp_gen = fasttrap_mod_gen; 845179193Sjb return; 846179193Sjb } 847179193Sjb 848179193Sjb mutex_exit(&bucket->ftb_mtx); 849179193Sjb 850179193Sjb /* 851179193Sjb * We can't safely remove the tracepoint from the set of active 852179193Sjb * tracepoints until we've actually removed the fasttrap instruction 853179193Sjb * from the process's text. We can, however, operate on this 854179193Sjb * tracepoint secure in the knowledge that no other thread is going to 855179193Sjb * be looking at it since we hold P_PR_LOCK on the process if it's 856179193Sjb * live or we hold the provider lock on the process if it's dead and 857179193Sjb * gone. 858179193Sjb */ 859179193Sjb 860179193Sjb /* 861179193Sjb * We only need to remove the actual instruction if we're looking 862179193Sjb * at an existing process 863179193Sjb */ 864179193Sjb if (p != NULL) { 865179193Sjb /* 866179193Sjb * If we fail to restore the instruction we need to kill 867179193Sjb * this process since it's in a completely unrecoverable 868179193Sjb * state. 869179193Sjb */ 870179193Sjb if (fasttrap_tracepoint_remove(p, tp) != 0) 871179193Sjb fasttrap_sigtrap(p, NULL, pc); 872179193Sjb 873179193Sjb /* 874179193Sjb * Decrement the count of the number of tracepoints active 875179193Sjb * in the victim process. 876179193Sjb */ 877211738Srpaulo#if defined(sun) 878179193Sjb ASSERT(p->p_proc_flag & P_PR_LOCK); 879211738Srpaulo#else 880211738Srpaulo PROC_LOCK_ASSERT(p, MA_OWNED); 881211738Srpaulo#endif 882179193Sjb p->p_dtrace_count--; 883179193Sjb } 884179193Sjb 885179193Sjb /* 886179193Sjb * Remove the probe from the hash table of active tracepoints. 887179193Sjb */ 888179193Sjb mutex_enter(&bucket->ftb_mtx); 889179193Sjb pp = (fasttrap_tracepoint_t **)&bucket->ftb_data; 890179193Sjb ASSERT(*pp != NULL); 891179193Sjb while (*pp != tp) { 892179193Sjb pp = &(*pp)->ftt_next; 893179193Sjb ASSERT(*pp != NULL); 894179193Sjb } 895179193Sjb 896179193Sjb *pp = tp->ftt_next; 897179193Sjb membar_producer(); 898179193Sjb 899179193Sjb mutex_exit(&bucket->ftb_mtx); 900179193Sjb 901179193Sjb /* 902179193Sjb * Tag the modified probe with the generation in which it was changed. 903179193Sjb */ 904179193Sjb probe->ftp_gen = fasttrap_mod_gen; 905179193Sjb} 906179193Sjb 907179193Sjbstatic void 908179193Sjbfasttrap_enable_callbacks(void) 909179193Sjb{ 910179193Sjb /* 911179193Sjb * We don't have to play the rw lock game here because we're 912179193Sjb * providing something rather than taking something away -- 913179193Sjb * we can be sure that no threads have tried to follow this 914179193Sjb * function pointer yet. 915179193Sjb */ 916179193Sjb mutex_enter(&fasttrap_count_mtx); 917179193Sjb if (fasttrap_pid_count == 0) { 918179193Sjb ASSERT(dtrace_pid_probe_ptr == NULL); 919179193Sjb ASSERT(dtrace_return_probe_ptr == NULL); 920179193Sjb dtrace_pid_probe_ptr = &fasttrap_pid_probe; 921179193Sjb dtrace_return_probe_ptr = &fasttrap_return_probe; 922179193Sjb } 923179193Sjb ASSERT(dtrace_pid_probe_ptr == &fasttrap_pid_probe); 924179193Sjb ASSERT(dtrace_return_probe_ptr == &fasttrap_return_probe); 925179193Sjb fasttrap_pid_count++; 926179193Sjb mutex_exit(&fasttrap_count_mtx); 927179193Sjb} 928179193Sjb 929179193Sjbstatic void 930179193Sjbfasttrap_disable_callbacks(void) 931179193Sjb{ 932211738Srpaulo#if defined(sun) 933179193Sjb ASSERT(MUTEX_HELD(&cpu_lock)); 934211738Srpaulo#endif 935179193Sjb 936211738Srpaulo 937179193Sjb mutex_enter(&fasttrap_count_mtx); 938179193Sjb ASSERT(fasttrap_pid_count > 0); 939179193Sjb fasttrap_pid_count--; 940179193Sjb if (fasttrap_pid_count == 0) { 941211738Srpaulo#if defined(sun) 942179193Sjb cpu_t *cur, *cpu = CPU; 943179193Sjb 944179193Sjb for (cur = cpu->cpu_next_onln; cur != cpu; 945179193Sjb cur = cur->cpu_next_onln) { 946179193Sjb rw_enter(&cur->cpu_ft_lock, RW_WRITER); 947179193Sjb } 948211738Srpaulo#endif 949179193Sjb dtrace_pid_probe_ptr = NULL; 950179193Sjb dtrace_return_probe_ptr = NULL; 951211738Srpaulo#if defined(sun) 952179193Sjb for (cur = cpu->cpu_next_onln; cur != cpu; 953179193Sjb cur = cur->cpu_next_onln) { 954179193Sjb rw_exit(&cur->cpu_ft_lock); 955179193Sjb } 956211738Srpaulo#endif 957179193Sjb } 958179193Sjb mutex_exit(&fasttrap_count_mtx); 959179193Sjb} 960179193Sjb 961179193Sjb/*ARGSUSED*/ 962179193Sjbstatic void 963179193Sjbfasttrap_pid_enable(void *arg, dtrace_id_t id, void *parg) 964179193Sjb{ 965179193Sjb fasttrap_probe_t *probe = parg; 966211738Srpaulo proc_t *p = NULL; 967179193Sjb int i, rc; 968179193Sjb 969211738Srpaulo 970179193Sjb ASSERT(probe != NULL); 971179193Sjb ASSERT(!probe->ftp_enabled); 972179193Sjb ASSERT(id == probe->ftp_id); 973211738Srpaulo#if defined(sun) 974179193Sjb ASSERT(MUTEX_HELD(&cpu_lock)); 975211738Srpaulo#endif 976179193Sjb 977179193Sjb /* 978179193Sjb * Increment the count of enabled probes on this probe's provider; 979179193Sjb * the provider can't go away while the probe still exists. We 980179193Sjb * must increment this even if we aren't able to properly enable 981179193Sjb * this probe. 982179193Sjb */ 983179193Sjb mutex_enter(&probe->ftp_prov->ftp_mtx); 984179193Sjb probe->ftp_prov->ftp_rcount++; 985179193Sjb mutex_exit(&probe->ftp_prov->ftp_mtx); 986179193Sjb 987179193Sjb /* 988179193Sjb * If this probe's provider is retired (meaning it was valid in a 989179193Sjb * previously exec'ed incarnation of this address space), bail out. The 990179193Sjb * provider can't go away while we're in this code path. 991179193Sjb */ 992179193Sjb if (probe->ftp_prov->ftp_retired) 993179193Sjb return; 994179193Sjb 995179193Sjb /* 996179193Sjb * If we can't find the process, it may be that we're in the context of 997179193Sjb * a fork in which the traced process is being born and we're copying 998179193Sjb * USDT probes. Otherwise, the process is gone so bail. 999179193Sjb */ 1000211738Srpaulo#if defined(sun) 1001179193Sjb if ((p = sprlock(probe->ftp_pid)) == NULL) { 1002179193Sjb if ((curproc->p_flag & SFORKING) == 0) 1003179193Sjb return; 1004179193Sjb 1005179193Sjb mutex_enter(&pidlock); 1006179193Sjb p = prfind(probe->ftp_pid); 1007179193Sjb 1008179193Sjb /* 1009179193Sjb * Confirm that curproc is indeed forking the process in which 1010179193Sjb * we're trying to enable probes. 1011179193Sjb */ 1012179193Sjb ASSERT(p != NULL); 1013179193Sjb ASSERT(p->p_parent == curproc); 1014179193Sjb ASSERT(p->p_stat == SIDL); 1015179193Sjb 1016179193Sjb mutex_enter(&p->p_lock); 1017179193Sjb mutex_exit(&pidlock); 1018179193Sjb 1019179193Sjb sprlock_proc(p); 1020179193Sjb } 1021179193Sjb 1022179193Sjb ASSERT(!(p->p_flag & SVFORK)); 1023179193Sjb mutex_exit(&p->p_lock); 1024211738Srpaulo#else 1025211738Srpaulo if ((p = pfind(probe->ftp_pid)) == NULL) 1026211738Srpaulo return; 1027211738Srpaulo#endif 1028179193Sjb 1029179193Sjb /* 1030179193Sjb * We have to enable the trap entry point before any user threads have 1031179193Sjb * the chance to execute the trap instruction we're about to place 1032179193Sjb * in their process's text. 1033179193Sjb */ 1034211738Srpaulo PROC_UNLOCK(p); 1035179193Sjb fasttrap_enable_callbacks(); 1036211738Srpaulo PROC_LOCK(p); 1037179193Sjb 1038179193Sjb /* 1039179193Sjb * Enable all the tracepoints and add this probe's id to each 1040179193Sjb * tracepoint's list of active probes. 1041179193Sjb */ 1042179193Sjb for (i = 0; i < probe->ftp_ntps; i++) { 1043179193Sjb if ((rc = fasttrap_tracepoint_enable(p, probe, i)) != 0) { 1044179193Sjb /* 1045179193Sjb * If enabling the tracepoint failed completely, 1046179193Sjb * we don't have to disable it; if the failure 1047179193Sjb * was only partial we must disable it. 1048179193Sjb */ 1049179193Sjb if (rc == FASTTRAP_ENABLE_FAIL) 1050179193Sjb i--; 1051179193Sjb else 1052179193Sjb ASSERT(rc == FASTTRAP_ENABLE_PARTIAL); 1053179193Sjb 1054179193Sjb /* 1055179193Sjb * Back up and pull out all the tracepoints we've 1056179193Sjb * created so far for this probe. 1057179193Sjb */ 1058179193Sjb while (i >= 0) { 1059179193Sjb fasttrap_tracepoint_disable(p, probe, i); 1060179193Sjb i--; 1061179193Sjb } 1062179193Sjb 1063211738Srpaulo#if defined(sun) 1064179193Sjb mutex_enter(&p->p_lock); 1065179193Sjb sprunlock(p); 1066211738Srpaulo#else 1067211738Srpaulo PROC_UNLOCK(p); 1068211738Srpaulo#endif 1069179193Sjb 1070179193Sjb /* 1071179193Sjb * Since we're not actually enabling this probe, 1072179193Sjb * drop our reference on the trap table entry. 1073179193Sjb */ 1074179193Sjb fasttrap_disable_callbacks(); 1075179193Sjb return; 1076179193Sjb } 1077179193Sjb } 1078211738Srpaulo#if defined(sun) 1079179193Sjb mutex_enter(&p->p_lock); 1080179193Sjb sprunlock(p); 1081211738Srpaulo#else 1082211738Srpaulo PROC_UNLOCK(p); 1083211738Srpaulo#endif 1084179193Sjb 1085179193Sjb probe->ftp_enabled = 1; 1086179193Sjb} 1087179193Sjb 1088179193Sjb/*ARGSUSED*/ 1089179193Sjbstatic void 1090179193Sjbfasttrap_pid_disable(void *arg, dtrace_id_t id, void *parg) 1091179193Sjb{ 1092179193Sjb fasttrap_probe_t *probe = parg; 1093179193Sjb fasttrap_provider_t *provider = probe->ftp_prov; 1094179193Sjb proc_t *p; 1095179193Sjb int i, whack = 0; 1096179193Sjb 1097179193Sjb ASSERT(id == probe->ftp_id); 1098179193Sjb 1099211738Srpaulo mutex_enter(&provider->ftp_mtx); 1100211738Srpaulo 1101179193Sjb /* 1102179193Sjb * We won't be able to acquire a /proc-esque lock on the process 1103179193Sjb * iff the process is dead and gone. In this case, we rely on the 1104179193Sjb * provider lock as a point of mutual exclusion to prevent other 1105179193Sjb * DTrace consumers from disabling this probe. 1106179193Sjb */ 1107211738Srpaulo if ((p = pfind(probe->ftp_pid)) == NULL) { 1108211738Srpaulo mutex_exit(&provider->ftp_mtx); 1109211738Srpaulo return; 1110179193Sjb } 1111179193Sjb 1112179193Sjb /* 1113179193Sjb * Disable all the associated tracepoints (for fully enabled probes). 1114179193Sjb */ 1115179193Sjb if (probe->ftp_enabled) { 1116179193Sjb for (i = 0; i < probe->ftp_ntps; i++) { 1117179193Sjb fasttrap_tracepoint_disable(p, probe, i); 1118179193Sjb } 1119179193Sjb } 1120179193Sjb 1121179193Sjb ASSERT(provider->ftp_rcount > 0); 1122179193Sjb provider->ftp_rcount--; 1123179193Sjb 1124179193Sjb if (p != NULL) { 1125179193Sjb /* 1126179193Sjb * Even though we may not be able to remove it entirely, we 1127179193Sjb * mark this retired provider to get a chance to remove some 1128179193Sjb * of the associated probes. 1129179193Sjb */ 1130179193Sjb if (provider->ftp_retired && !provider->ftp_marked) 1131179193Sjb whack = provider->ftp_marked = 1; 1132179193Sjb mutex_exit(&provider->ftp_mtx); 1133179193Sjb } else { 1134179193Sjb /* 1135179193Sjb * If the process is dead, we're just waiting for the 1136179193Sjb * last probe to be disabled to be able to free it. 1137179193Sjb */ 1138179193Sjb if (provider->ftp_rcount == 0 && !provider->ftp_marked) 1139179193Sjb whack = provider->ftp_marked = 1; 1140179193Sjb mutex_exit(&provider->ftp_mtx); 1141179193Sjb } 1142211738Srpaulo#if !defined(sun) 1143211738Srpaulo PROC_UNLOCK(p); 1144211738Srpaulo#endif 1145179193Sjb 1146179193Sjb if (whack) 1147179193Sjb fasttrap_pid_cleanup(); 1148179193Sjb 1149179193Sjb if (!probe->ftp_enabled) 1150179193Sjb return; 1151179193Sjb 1152179193Sjb probe->ftp_enabled = 0; 1153179193Sjb 1154211738Srpaulo#if defined(sun) 1155179193Sjb ASSERT(MUTEX_HELD(&cpu_lock)); 1156211738Srpaulo#endif 1157179193Sjb fasttrap_disable_callbacks(); 1158179193Sjb} 1159179193Sjb 1160179193Sjb/*ARGSUSED*/ 1161179193Sjbstatic void 1162179193Sjbfasttrap_pid_getargdesc(void *arg, dtrace_id_t id, void *parg, 1163179193Sjb dtrace_argdesc_t *desc) 1164179193Sjb{ 1165179193Sjb fasttrap_probe_t *probe = parg; 1166179193Sjb char *str; 1167179193Sjb int i, ndx; 1168179193Sjb 1169179193Sjb desc->dtargd_native[0] = '\0'; 1170179193Sjb desc->dtargd_xlate[0] = '\0'; 1171179193Sjb 1172179193Sjb if (probe->ftp_prov->ftp_retired != 0 || 1173179193Sjb desc->dtargd_ndx >= probe->ftp_nargs) { 1174179193Sjb desc->dtargd_ndx = DTRACE_ARGNONE; 1175179193Sjb return; 1176179193Sjb } 1177179193Sjb 1178179193Sjb ndx = (probe->ftp_argmap != NULL) ? 1179179193Sjb probe->ftp_argmap[desc->dtargd_ndx] : desc->dtargd_ndx; 1180179193Sjb 1181179193Sjb str = probe->ftp_ntypes; 1182179193Sjb for (i = 0; i < ndx; i++) { 1183179193Sjb str += strlen(str) + 1; 1184179193Sjb } 1185179193Sjb 1186179193Sjb ASSERT(strlen(str + 1) < sizeof (desc->dtargd_native)); 1187179193Sjb (void) strcpy(desc->dtargd_native, str); 1188179193Sjb 1189179193Sjb if (probe->ftp_xtypes == NULL) 1190179193Sjb return; 1191179193Sjb 1192179193Sjb str = probe->ftp_xtypes; 1193179193Sjb for (i = 0; i < desc->dtargd_ndx; i++) { 1194179193Sjb str += strlen(str) + 1; 1195179193Sjb } 1196179193Sjb 1197179193Sjb ASSERT(strlen(str + 1) < sizeof (desc->dtargd_xlate)); 1198179193Sjb (void) strcpy(desc->dtargd_xlate, str); 1199179193Sjb} 1200179193Sjb 1201179193Sjb/*ARGSUSED*/ 1202179193Sjbstatic void 1203179193Sjbfasttrap_pid_destroy(void *arg, dtrace_id_t id, void *parg) 1204179193Sjb{ 1205179193Sjb fasttrap_probe_t *probe = parg; 1206179193Sjb int i; 1207179193Sjb size_t size; 1208179193Sjb 1209179193Sjb ASSERT(probe != NULL); 1210179193Sjb ASSERT(!probe->ftp_enabled); 1211179193Sjb ASSERT(fasttrap_total >= probe->ftp_ntps); 1212179193Sjb 1213179193Sjb atomic_add_32(&fasttrap_total, -probe->ftp_ntps); 1214179193Sjb size = offsetof(fasttrap_probe_t, ftp_tps[probe->ftp_ntps]); 1215179193Sjb 1216179193Sjb if (probe->ftp_gen + 1 >= fasttrap_mod_gen) 1217179193Sjb fasttrap_mod_barrier(probe->ftp_gen); 1218179193Sjb 1219179193Sjb for (i = 0; i < probe->ftp_ntps; i++) { 1220179193Sjb kmem_free(probe->ftp_tps[i].fit_tp, 1221179193Sjb sizeof (fasttrap_tracepoint_t)); 1222179193Sjb } 1223179193Sjb 1224179193Sjb kmem_free(probe, size); 1225179193Sjb} 1226179193Sjb 1227179193Sjb 1228179193Sjbstatic const dtrace_pattr_t pid_attr = { 1229179193Sjb{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_ISA }, 1230179193Sjb{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN }, 1231179193Sjb{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN }, 1232179193Sjb{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_ISA }, 1233179193Sjb{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN }, 1234179193Sjb}; 1235179193Sjb 1236179193Sjbstatic dtrace_pops_t pid_pops = { 1237179193Sjb fasttrap_pid_provide, 1238179193Sjb NULL, 1239179193Sjb fasttrap_pid_enable, 1240179193Sjb fasttrap_pid_disable, 1241179193Sjb NULL, 1242179193Sjb NULL, 1243179193Sjb fasttrap_pid_getargdesc, 1244179193Sjb fasttrap_pid_getarg, 1245179193Sjb NULL, 1246179193Sjb fasttrap_pid_destroy 1247179193Sjb}; 1248179193Sjb 1249179193Sjbstatic dtrace_pops_t usdt_pops = { 1250179193Sjb fasttrap_pid_provide, 1251179193Sjb NULL, 1252179193Sjb fasttrap_pid_enable, 1253179193Sjb fasttrap_pid_disable, 1254179193Sjb NULL, 1255179193Sjb NULL, 1256179193Sjb fasttrap_pid_getargdesc, 1257179193Sjb fasttrap_usdt_getarg, 1258179193Sjb NULL, 1259179193Sjb fasttrap_pid_destroy 1260179193Sjb}; 1261179193Sjb 1262179193Sjbstatic fasttrap_proc_t * 1263179193Sjbfasttrap_proc_lookup(pid_t pid) 1264179193Sjb{ 1265179193Sjb fasttrap_bucket_t *bucket; 1266179193Sjb fasttrap_proc_t *fprc, *new_fprc; 1267179193Sjb 1268211738Srpaulo 1269179193Sjb bucket = &fasttrap_procs.fth_table[FASTTRAP_PROCS_INDEX(pid)]; 1270179193Sjb mutex_enter(&bucket->ftb_mtx); 1271179193Sjb 1272179193Sjb for (fprc = bucket->ftb_data; fprc != NULL; fprc = fprc->ftpc_next) { 1273179193Sjb if (fprc->ftpc_pid == pid && fprc->ftpc_acount != 0) { 1274179193Sjb mutex_enter(&fprc->ftpc_mtx); 1275179193Sjb mutex_exit(&bucket->ftb_mtx); 1276179193Sjb fprc->ftpc_rcount++; 1277179193Sjb atomic_add_64(&fprc->ftpc_acount, 1); 1278179198Sjb ASSERT(fprc->ftpc_acount <= fprc->ftpc_rcount); 1279179193Sjb mutex_exit(&fprc->ftpc_mtx); 1280179193Sjb 1281179193Sjb return (fprc); 1282179193Sjb } 1283179193Sjb } 1284179193Sjb 1285179193Sjb /* 1286179193Sjb * Drop the bucket lock so we don't try to perform a sleeping 1287179193Sjb * allocation under it. 1288179193Sjb */ 1289179193Sjb mutex_exit(&bucket->ftb_mtx); 1290179193Sjb 1291179193Sjb new_fprc = kmem_zalloc(sizeof (fasttrap_proc_t), KM_SLEEP); 1292179193Sjb new_fprc->ftpc_pid = pid; 1293179193Sjb new_fprc->ftpc_rcount = 1; 1294179193Sjb new_fprc->ftpc_acount = 1; 1295211738Srpaulo#if !defined(sun) 1296211738Srpaulo mutex_init(&new_fprc->ftpc_mtx, "fasttrap proc mtx", MUTEX_DEFAULT, 1297211738Srpaulo NULL); 1298211738Srpaulo#endif 1299179193Sjb 1300179193Sjb mutex_enter(&bucket->ftb_mtx); 1301179193Sjb 1302179193Sjb /* 1303179193Sjb * Take another lap through the list to make sure a proc hasn't 1304179193Sjb * been created for this pid while we weren't under the bucket lock. 1305179193Sjb */ 1306179193Sjb for (fprc = bucket->ftb_data; fprc != NULL; fprc = fprc->ftpc_next) { 1307179193Sjb if (fprc->ftpc_pid == pid && fprc->ftpc_acount != 0) { 1308179193Sjb mutex_enter(&fprc->ftpc_mtx); 1309179193Sjb mutex_exit(&bucket->ftb_mtx); 1310179193Sjb fprc->ftpc_rcount++; 1311179193Sjb atomic_add_64(&fprc->ftpc_acount, 1); 1312179198Sjb ASSERT(fprc->ftpc_acount <= fprc->ftpc_rcount); 1313179193Sjb mutex_exit(&fprc->ftpc_mtx); 1314179193Sjb 1315179193Sjb kmem_free(new_fprc, sizeof (fasttrap_proc_t)); 1316179193Sjb 1317179193Sjb return (fprc); 1318179193Sjb } 1319179193Sjb } 1320179193Sjb 1321179193Sjb new_fprc->ftpc_next = bucket->ftb_data; 1322179193Sjb bucket->ftb_data = new_fprc; 1323179193Sjb 1324179193Sjb mutex_exit(&bucket->ftb_mtx); 1325179193Sjb 1326179193Sjb return (new_fprc); 1327179193Sjb} 1328179193Sjb 1329179193Sjbstatic void 1330179193Sjbfasttrap_proc_release(fasttrap_proc_t *proc) 1331179193Sjb{ 1332179193Sjb fasttrap_bucket_t *bucket; 1333179193Sjb fasttrap_proc_t *fprc, **fprcp; 1334179193Sjb pid_t pid = proc->ftpc_pid; 1335179193Sjb 1336179193Sjb mutex_enter(&proc->ftpc_mtx); 1337179193Sjb 1338179193Sjb ASSERT(proc->ftpc_rcount != 0); 1339179198Sjb ASSERT(proc->ftpc_acount <= proc->ftpc_rcount); 1340179193Sjb 1341179193Sjb if (--proc->ftpc_rcount != 0) { 1342179193Sjb mutex_exit(&proc->ftpc_mtx); 1343179193Sjb return; 1344179193Sjb } 1345179193Sjb 1346179193Sjb mutex_exit(&proc->ftpc_mtx); 1347179193Sjb 1348179193Sjb /* 1349179193Sjb * There should definitely be no live providers associated with this 1350179193Sjb * process at this point. 1351179193Sjb */ 1352179193Sjb ASSERT(proc->ftpc_acount == 0); 1353179193Sjb 1354179193Sjb bucket = &fasttrap_procs.fth_table[FASTTRAP_PROCS_INDEX(pid)]; 1355179193Sjb mutex_enter(&bucket->ftb_mtx); 1356179193Sjb 1357179193Sjb fprcp = (fasttrap_proc_t **)&bucket->ftb_data; 1358179193Sjb while ((fprc = *fprcp) != NULL) { 1359179193Sjb if (fprc == proc) 1360179193Sjb break; 1361179193Sjb 1362179193Sjb fprcp = &fprc->ftpc_next; 1363179193Sjb } 1364179193Sjb 1365179193Sjb /* 1366179193Sjb * Something strange has happened if we can't find the proc. 1367179193Sjb */ 1368179193Sjb ASSERT(fprc != NULL); 1369179193Sjb 1370179193Sjb *fprcp = fprc->ftpc_next; 1371179193Sjb 1372179193Sjb mutex_exit(&bucket->ftb_mtx); 1373179193Sjb 1374179193Sjb kmem_free(fprc, sizeof (fasttrap_proc_t)); 1375179193Sjb} 1376179193Sjb 1377179193Sjb/* 1378179193Sjb * Lookup a fasttrap-managed provider based on its name and associated pid. 1379179193Sjb * If the pattr argument is non-NULL, this function instantiates the provider 1380179193Sjb * if it doesn't exist otherwise it returns NULL. The provider is returned 1381179193Sjb * with its lock held. 1382179193Sjb */ 1383179193Sjbstatic fasttrap_provider_t * 1384179193Sjbfasttrap_provider_lookup(pid_t pid, const char *name, 1385179193Sjb const dtrace_pattr_t *pattr) 1386179193Sjb{ 1387179193Sjb fasttrap_provider_t *fp, *new_fp = NULL; 1388179193Sjb fasttrap_bucket_t *bucket; 1389179193Sjb char provname[DTRACE_PROVNAMELEN]; 1390179193Sjb proc_t *p; 1391179193Sjb cred_t *cred; 1392179193Sjb 1393179193Sjb ASSERT(strlen(name) < sizeof (fp->ftp_name)); 1394179193Sjb ASSERT(pattr != NULL); 1395179193Sjb 1396179193Sjb bucket = &fasttrap_provs.fth_table[FASTTRAP_PROVS_INDEX(pid, name)]; 1397179193Sjb mutex_enter(&bucket->ftb_mtx); 1398179193Sjb 1399179193Sjb /* 1400179193Sjb * Take a lap through the list and return the match if we find it. 1401179193Sjb */ 1402179193Sjb for (fp = bucket->ftb_data; fp != NULL; fp = fp->ftp_next) { 1403179193Sjb if (fp->ftp_pid == pid && strcmp(fp->ftp_name, name) == 0 && 1404179193Sjb !fp->ftp_retired) { 1405179193Sjb mutex_enter(&fp->ftp_mtx); 1406179193Sjb mutex_exit(&bucket->ftb_mtx); 1407179193Sjb return (fp); 1408179193Sjb } 1409179193Sjb } 1410179193Sjb 1411179193Sjb /* 1412179193Sjb * Drop the bucket lock so we don't try to perform a sleeping 1413179193Sjb * allocation under it. 1414179193Sjb */ 1415179193Sjb mutex_exit(&bucket->ftb_mtx); 1416179193Sjb 1417179193Sjb /* 1418179193Sjb * Make sure the process exists, isn't a child created as the result 1419179193Sjb * of a vfork(2), and isn't a zombie (but may be in fork). 1420179193Sjb */ 1421211738Srpaulo if ((p = pfind(pid)) == NULL) 1422179193Sjb return (NULL); 1423179193Sjb 1424179193Sjb /* 1425179193Sjb * Increment p_dtrace_probes so that the process knows to inform us 1426179193Sjb * when it exits or execs. fasttrap_provider_free() decrements this 1427179193Sjb * when we're done with this provider. 1428179193Sjb */ 1429179193Sjb p->p_dtrace_probes++; 1430179193Sjb 1431179193Sjb /* 1432179193Sjb * Grab the credentials for this process so we have 1433179193Sjb * something to pass to dtrace_register(). 1434179193Sjb */ 1435211738Srpaulo PROC_LOCK_ASSERT(p, MA_OWNED); 1436211738Srpaulo crhold(p->p_ucred); 1437211738Srpaulo cred = p->p_ucred; 1438211738Srpaulo PROC_UNLOCK(p); 1439179193Sjb 1440179193Sjb new_fp = kmem_zalloc(sizeof (fasttrap_provider_t), KM_SLEEP); 1441179193Sjb new_fp->ftp_pid = pid; 1442179193Sjb new_fp->ftp_proc = fasttrap_proc_lookup(pid); 1443211738Srpaulo#if !defined(sun) 1444211738Srpaulo mutex_init(&new_fp->ftp_mtx, "provider mtx", MUTEX_DEFAULT, NULL); 1445211738Srpaulo mutex_init(&new_fp->ftp_cmtx, "lock on creating", MUTEX_DEFAULT, NULL); 1446211738Srpaulo#endif 1447179193Sjb 1448179193Sjb ASSERT(new_fp->ftp_proc != NULL); 1449179193Sjb 1450179193Sjb mutex_enter(&bucket->ftb_mtx); 1451179193Sjb 1452179193Sjb /* 1453179193Sjb * Take another lap through the list to make sure a provider hasn't 1454179193Sjb * been created for this pid while we weren't under the bucket lock. 1455179193Sjb */ 1456179193Sjb for (fp = bucket->ftb_data; fp != NULL; fp = fp->ftp_next) { 1457179193Sjb if (fp->ftp_pid == pid && strcmp(fp->ftp_name, name) == 0 && 1458179193Sjb !fp->ftp_retired) { 1459179193Sjb mutex_enter(&fp->ftp_mtx); 1460179193Sjb mutex_exit(&bucket->ftb_mtx); 1461179193Sjb fasttrap_provider_free(new_fp); 1462179193Sjb crfree(cred); 1463179193Sjb return (fp); 1464179193Sjb } 1465179193Sjb } 1466179193Sjb 1467179193Sjb (void) strcpy(new_fp->ftp_name, name); 1468179193Sjb 1469179193Sjb /* 1470179193Sjb * Fail and return NULL if either the provider name is too long 1471179193Sjb * or we fail to register this new provider with the DTrace 1472179193Sjb * framework. Note that this is the only place we ever construct 1473179193Sjb * the full provider name -- we keep it in pieces in the provider 1474179193Sjb * structure. 1475179193Sjb */ 1476179193Sjb if (snprintf(provname, sizeof (provname), "%s%u", name, (uint_t)pid) >= 1477179193Sjb sizeof (provname) || 1478179193Sjb dtrace_register(provname, pattr, 1479179193Sjb DTRACE_PRIV_PROC | DTRACE_PRIV_OWNER | DTRACE_PRIV_ZONEOWNER, cred, 1480179193Sjb pattr == &pid_attr ? &pid_pops : &usdt_pops, new_fp, 1481179193Sjb &new_fp->ftp_provid) != 0) { 1482179193Sjb mutex_exit(&bucket->ftb_mtx); 1483179193Sjb fasttrap_provider_free(new_fp); 1484179193Sjb crfree(cred); 1485179193Sjb return (NULL); 1486179193Sjb } 1487179193Sjb 1488179193Sjb new_fp->ftp_next = bucket->ftb_data; 1489179193Sjb bucket->ftb_data = new_fp; 1490179193Sjb 1491179193Sjb mutex_enter(&new_fp->ftp_mtx); 1492179193Sjb mutex_exit(&bucket->ftb_mtx); 1493179193Sjb 1494179193Sjb crfree(cred); 1495179193Sjb return (new_fp); 1496179193Sjb} 1497179193Sjb 1498179193Sjbstatic void 1499179193Sjbfasttrap_provider_free(fasttrap_provider_t *provider) 1500179193Sjb{ 1501179193Sjb pid_t pid = provider->ftp_pid; 1502179193Sjb proc_t *p; 1503179193Sjb 1504179193Sjb /* 1505179193Sjb * There need to be no associated enabled probes, no consumers 1506179193Sjb * creating probes, and no meta providers referencing this provider. 1507179193Sjb */ 1508179193Sjb ASSERT(provider->ftp_rcount == 0); 1509179193Sjb ASSERT(provider->ftp_ccount == 0); 1510179193Sjb ASSERT(provider->ftp_mcount == 0); 1511179193Sjb 1512179198Sjb /* 1513179198Sjb * If this provider hasn't been retired, we need to explicitly drop the 1514179198Sjb * count of active providers on the associated process structure. 1515179198Sjb */ 1516179198Sjb if (!provider->ftp_retired) { 1517179198Sjb atomic_add_64(&provider->ftp_proc->ftpc_acount, -1); 1518179198Sjb ASSERT(provider->ftp_proc->ftpc_acount < 1519179198Sjb provider->ftp_proc->ftpc_rcount); 1520179198Sjb } 1521179198Sjb 1522179193Sjb fasttrap_proc_release(provider->ftp_proc); 1523179193Sjb 1524211738Srpaulo#if !defined(sun) 1525211738Srpaulo mutex_destroy(&provider->ftp_mtx); 1526211738Srpaulo mutex_destroy(&provider->ftp_cmtx); 1527211738Srpaulo#endif 1528179193Sjb kmem_free(provider, sizeof (fasttrap_provider_t)); 1529179193Sjb 1530179193Sjb /* 1531179193Sjb * Decrement p_dtrace_probes on the process whose provider we're 1532179193Sjb * freeing. We don't have to worry about clobbering somone else's 1533179193Sjb * modifications to it because we have locked the bucket that 1534179193Sjb * corresponds to this process's hash chain in the provider hash 1535179193Sjb * table. Don't sweat it if we can't find the process. 1536179193Sjb */ 1537211738Srpaulo if ((p = pfind(pid)) == NULL) { 1538179193Sjb return; 1539179193Sjb } 1540179193Sjb 1541179193Sjb p->p_dtrace_probes--; 1542211738Srpaulo#if !defined(sun) 1543211738Srpaulo PROC_UNLOCK(p); 1544211738Srpaulo#endif 1545179193Sjb} 1546179193Sjb 1547179193Sjbstatic void 1548179193Sjbfasttrap_provider_retire(pid_t pid, const char *name, int mprov) 1549179193Sjb{ 1550179193Sjb fasttrap_provider_t *fp; 1551179193Sjb fasttrap_bucket_t *bucket; 1552179193Sjb dtrace_provider_id_t provid; 1553179193Sjb 1554179193Sjb ASSERT(strlen(name) < sizeof (fp->ftp_name)); 1555179193Sjb 1556179193Sjb bucket = &fasttrap_provs.fth_table[FASTTRAP_PROVS_INDEX(pid, name)]; 1557179193Sjb mutex_enter(&bucket->ftb_mtx); 1558179193Sjb 1559179193Sjb for (fp = bucket->ftb_data; fp != NULL; fp = fp->ftp_next) { 1560179193Sjb if (fp->ftp_pid == pid && strcmp(fp->ftp_name, name) == 0 && 1561179193Sjb !fp->ftp_retired) 1562179193Sjb break; 1563179193Sjb } 1564179193Sjb 1565179193Sjb if (fp == NULL) { 1566179193Sjb mutex_exit(&bucket->ftb_mtx); 1567179193Sjb return; 1568179193Sjb } 1569179193Sjb 1570179193Sjb mutex_enter(&fp->ftp_mtx); 1571179193Sjb ASSERT(!mprov || fp->ftp_mcount > 0); 1572179193Sjb if (mprov && --fp->ftp_mcount != 0) { 1573179193Sjb mutex_exit(&fp->ftp_mtx); 1574179193Sjb mutex_exit(&bucket->ftb_mtx); 1575179193Sjb return; 1576179193Sjb } 1577179193Sjb 1578179193Sjb /* 1579179193Sjb * Mark the provider to be removed in our post-processing step, mark it 1580179193Sjb * retired, and drop the active count on its proc. Marking it indicates 1581179193Sjb * that we should try to remove it; setting the retired flag indicates 1582179193Sjb * that we're done with this provider; dropping the active the proc 1583179193Sjb * releases our hold, and when this reaches zero (as it will during 1584179193Sjb * exit or exec) the proc and associated providers become defunct. 1585179193Sjb * 1586179193Sjb * We obviously need to take the bucket lock before the provider lock 1587179193Sjb * to perform the lookup, but we need to drop the provider lock 1588179193Sjb * before calling into the DTrace framework since we acquire the 1589179193Sjb * provider lock in callbacks invoked from the DTrace framework. The 1590179193Sjb * bucket lock therefore protects the integrity of the provider hash 1591179193Sjb * table. 1592179193Sjb */ 1593179193Sjb atomic_add_64(&fp->ftp_proc->ftpc_acount, -1); 1594179198Sjb ASSERT(fp->ftp_proc->ftpc_acount < fp->ftp_proc->ftpc_rcount); 1595179198Sjb 1596179193Sjb fp->ftp_retired = 1; 1597179193Sjb fp->ftp_marked = 1; 1598179193Sjb provid = fp->ftp_provid; 1599179193Sjb mutex_exit(&fp->ftp_mtx); 1600179193Sjb 1601179193Sjb /* 1602179193Sjb * We don't have to worry about invalidating the same provider twice 1603179193Sjb * since fasttrap_provider_lookup() will ignore provider that have 1604179193Sjb * been marked as retired. 1605179193Sjb */ 1606179193Sjb dtrace_invalidate(provid); 1607179193Sjb 1608179193Sjb mutex_exit(&bucket->ftb_mtx); 1609179193Sjb 1610179193Sjb fasttrap_pid_cleanup(); 1611179193Sjb} 1612179193Sjb 1613179193Sjbstatic int 1614179193Sjbfasttrap_uint32_cmp(const void *ap, const void *bp) 1615179193Sjb{ 1616179193Sjb return (*(const uint32_t *)ap - *(const uint32_t *)bp); 1617179193Sjb} 1618179193Sjb 1619179193Sjbstatic int 1620179193Sjbfasttrap_uint64_cmp(const void *ap, const void *bp) 1621179193Sjb{ 1622179193Sjb return (*(const uint64_t *)ap - *(const uint64_t *)bp); 1623179193Sjb} 1624179193Sjb 1625179193Sjbstatic int 1626179193Sjbfasttrap_add_probe(fasttrap_probe_spec_t *pdata) 1627179193Sjb{ 1628179193Sjb fasttrap_provider_t *provider; 1629179193Sjb fasttrap_probe_t *pp; 1630179193Sjb fasttrap_tracepoint_t *tp; 1631179193Sjb char *name; 1632211738Srpaulo int i, aframes = 0, whack; 1633179193Sjb 1634179193Sjb /* 1635179193Sjb * There needs to be at least one desired trace point. 1636179193Sjb */ 1637179193Sjb if (pdata->ftps_noffs == 0) 1638179193Sjb return (EINVAL); 1639179193Sjb 1640179193Sjb switch (pdata->ftps_type) { 1641179193Sjb case DTFTP_ENTRY: 1642179193Sjb name = "entry"; 1643179193Sjb aframes = FASTTRAP_ENTRY_AFRAMES; 1644179193Sjb break; 1645179193Sjb case DTFTP_RETURN: 1646179193Sjb name = "return"; 1647179193Sjb aframes = FASTTRAP_RETURN_AFRAMES; 1648179193Sjb break; 1649179193Sjb case DTFTP_OFFSETS: 1650179193Sjb name = NULL; 1651179193Sjb break; 1652179193Sjb default: 1653179193Sjb return (EINVAL); 1654179193Sjb } 1655179193Sjb 1656179193Sjb if ((provider = fasttrap_provider_lookup(pdata->ftps_pid, 1657179193Sjb FASTTRAP_PID_NAME, &pid_attr)) == NULL) 1658179193Sjb return (ESRCH); 1659179193Sjb 1660179193Sjb /* 1661179193Sjb * Increment this reference count to indicate that a consumer is 1662179193Sjb * actively adding a new probe associated with this provider. This 1663179193Sjb * prevents the provider from being deleted -- we'll need to check 1664179193Sjb * for pending deletions when we drop this reference count. 1665179193Sjb */ 1666179193Sjb provider->ftp_ccount++; 1667179193Sjb mutex_exit(&provider->ftp_mtx); 1668179193Sjb 1669179193Sjb /* 1670179193Sjb * Grab the creation lock to ensure consistency between calls to 1671179193Sjb * dtrace_probe_lookup() and dtrace_probe_create() in the face of 1672179193Sjb * other threads creating probes. We must drop the provider lock 1673179193Sjb * before taking this lock to avoid a three-way deadlock with the 1674179193Sjb * DTrace framework. 1675179193Sjb */ 1676179193Sjb mutex_enter(&provider->ftp_cmtx); 1677179193Sjb 1678179193Sjb if (name == NULL) { 1679179193Sjb for (i = 0; i < pdata->ftps_noffs; i++) { 1680179193Sjb char name_str[17]; 1681179193Sjb 1682179193Sjb (void) sprintf(name_str, "%llx", 1683179193Sjb (unsigned long long)pdata->ftps_offs[i]); 1684179193Sjb 1685179193Sjb if (dtrace_probe_lookup(provider->ftp_provid, 1686179193Sjb pdata->ftps_mod, pdata->ftps_func, name_str) != 0) 1687179193Sjb continue; 1688179193Sjb 1689179193Sjb atomic_add_32(&fasttrap_total, 1); 1690179193Sjb 1691179193Sjb if (fasttrap_total > fasttrap_max) { 1692179193Sjb atomic_add_32(&fasttrap_total, -1); 1693179193Sjb goto no_mem; 1694179193Sjb } 1695179193Sjb 1696179193Sjb pp = kmem_zalloc(sizeof (fasttrap_probe_t), KM_SLEEP); 1697179193Sjb 1698179193Sjb pp->ftp_prov = provider; 1699179193Sjb pp->ftp_faddr = pdata->ftps_pc; 1700179193Sjb pp->ftp_fsize = pdata->ftps_size; 1701179193Sjb pp->ftp_pid = pdata->ftps_pid; 1702179193Sjb pp->ftp_ntps = 1; 1703179193Sjb 1704179193Sjb tp = kmem_zalloc(sizeof (fasttrap_tracepoint_t), 1705179193Sjb KM_SLEEP); 1706179193Sjb 1707179193Sjb tp->ftt_proc = provider->ftp_proc; 1708179193Sjb tp->ftt_pc = pdata->ftps_offs[i] + pdata->ftps_pc; 1709179193Sjb tp->ftt_pid = pdata->ftps_pid; 1710179193Sjb 1711179193Sjb pp->ftp_tps[0].fit_tp = tp; 1712179193Sjb pp->ftp_tps[0].fit_id.fti_probe = pp; 1713179193Sjb pp->ftp_tps[0].fit_id.fti_ptype = pdata->ftps_type; 1714179193Sjb 1715179193Sjb pp->ftp_id = dtrace_probe_create(provider->ftp_provid, 1716179193Sjb pdata->ftps_mod, pdata->ftps_func, name_str, 1717179193Sjb FASTTRAP_OFFSET_AFRAMES, pp); 1718179193Sjb } 1719179193Sjb 1720179193Sjb } else if (dtrace_probe_lookup(provider->ftp_provid, pdata->ftps_mod, 1721179193Sjb pdata->ftps_func, name) == 0) { 1722179193Sjb atomic_add_32(&fasttrap_total, pdata->ftps_noffs); 1723179193Sjb 1724179193Sjb if (fasttrap_total > fasttrap_max) { 1725179193Sjb atomic_add_32(&fasttrap_total, -pdata->ftps_noffs); 1726179193Sjb goto no_mem; 1727179193Sjb } 1728179193Sjb 1729179193Sjb /* 1730179193Sjb * Make sure all tracepoint program counter values are unique. 1731179193Sjb * We later assume that each probe has exactly one tracepoint 1732179193Sjb * for a given pc. 1733179193Sjb */ 1734179193Sjb qsort(pdata->ftps_offs, pdata->ftps_noffs, 1735179193Sjb sizeof (uint64_t), fasttrap_uint64_cmp); 1736179193Sjb for (i = 1; i < pdata->ftps_noffs; i++) { 1737179193Sjb if (pdata->ftps_offs[i] > pdata->ftps_offs[i - 1]) 1738179193Sjb continue; 1739179193Sjb 1740179193Sjb atomic_add_32(&fasttrap_total, -pdata->ftps_noffs); 1741179193Sjb goto no_mem; 1742179193Sjb } 1743179193Sjb 1744179193Sjb ASSERT(pdata->ftps_noffs > 0); 1745179193Sjb pp = kmem_zalloc(offsetof(fasttrap_probe_t, 1746179193Sjb ftp_tps[pdata->ftps_noffs]), KM_SLEEP); 1747179193Sjb 1748179193Sjb pp->ftp_prov = provider; 1749179193Sjb pp->ftp_faddr = pdata->ftps_pc; 1750179193Sjb pp->ftp_fsize = pdata->ftps_size; 1751179193Sjb pp->ftp_pid = pdata->ftps_pid; 1752179193Sjb pp->ftp_ntps = pdata->ftps_noffs; 1753179193Sjb 1754179193Sjb for (i = 0; i < pdata->ftps_noffs; i++) { 1755179193Sjb tp = kmem_zalloc(sizeof (fasttrap_tracepoint_t), 1756179193Sjb KM_SLEEP); 1757179193Sjb 1758179193Sjb tp->ftt_proc = provider->ftp_proc; 1759179193Sjb tp->ftt_pc = pdata->ftps_offs[i] + pdata->ftps_pc; 1760179193Sjb tp->ftt_pid = pdata->ftps_pid; 1761179193Sjb 1762179193Sjb pp->ftp_tps[i].fit_tp = tp; 1763179193Sjb pp->ftp_tps[i].fit_id.fti_probe = pp; 1764179193Sjb pp->ftp_tps[i].fit_id.fti_ptype = pdata->ftps_type; 1765179193Sjb } 1766179193Sjb 1767179193Sjb pp->ftp_id = dtrace_probe_create(provider->ftp_provid, 1768179193Sjb pdata->ftps_mod, pdata->ftps_func, name, aframes, pp); 1769179193Sjb } 1770179193Sjb 1771179193Sjb mutex_exit(&provider->ftp_cmtx); 1772179193Sjb 1773179193Sjb /* 1774179193Sjb * We know that the provider is still valid since we incremented the 1775179193Sjb * creation reference count. If someone tried to clean up this provider 1776179193Sjb * while we were using it (e.g. because the process called exec(2) or 1777179193Sjb * exit(2)), take note of that and try to clean it up now. 1778179193Sjb */ 1779179193Sjb mutex_enter(&provider->ftp_mtx); 1780179193Sjb provider->ftp_ccount--; 1781179193Sjb whack = provider->ftp_retired; 1782179193Sjb mutex_exit(&provider->ftp_mtx); 1783179193Sjb 1784179193Sjb if (whack) 1785179193Sjb fasttrap_pid_cleanup(); 1786179193Sjb 1787179193Sjb return (0); 1788179193Sjb 1789179193Sjbno_mem: 1790179193Sjb /* 1791179193Sjb * If we've exhausted the allowable resources, we'll try to remove 1792179193Sjb * this provider to free some up. This is to cover the case where 1793179193Sjb * the user has accidentally created many more probes than was 1794179193Sjb * intended (e.g. pid123:::). 1795179193Sjb */ 1796179193Sjb mutex_exit(&provider->ftp_cmtx); 1797179193Sjb mutex_enter(&provider->ftp_mtx); 1798179193Sjb provider->ftp_ccount--; 1799179193Sjb provider->ftp_marked = 1; 1800179193Sjb mutex_exit(&provider->ftp_mtx); 1801179193Sjb 1802179193Sjb fasttrap_pid_cleanup(); 1803179193Sjb 1804179193Sjb return (ENOMEM); 1805179193Sjb} 1806179193Sjb 1807179193Sjb/*ARGSUSED*/ 1808179193Sjbstatic void * 1809179193Sjbfasttrap_meta_provide(void *arg, dtrace_helper_provdesc_t *dhpv, pid_t pid) 1810179193Sjb{ 1811179193Sjb fasttrap_provider_t *provider; 1812179193Sjb 1813179193Sjb /* 1814179193Sjb * A 32-bit unsigned integer (like a pid for example) can be 1815179193Sjb * expressed in 10 or fewer decimal digits. Make sure that we'll 1816179193Sjb * have enough space for the provider name. 1817179193Sjb */ 1818179193Sjb if (strlen(dhpv->dthpv_provname) + 10 >= 1819179193Sjb sizeof (provider->ftp_name)) { 1820211738Srpaulo printf("failed to instantiate provider %s: " 1821179193Sjb "name too long to accomodate pid", dhpv->dthpv_provname); 1822179193Sjb return (NULL); 1823179193Sjb } 1824179193Sjb 1825179193Sjb /* 1826179193Sjb * Don't let folks spoof the true pid provider. 1827179193Sjb */ 1828179193Sjb if (strcmp(dhpv->dthpv_provname, FASTTRAP_PID_NAME) == 0) { 1829211738Srpaulo printf("failed to instantiate provider %s: " 1830179193Sjb "%s is an invalid name", dhpv->dthpv_provname, 1831179193Sjb FASTTRAP_PID_NAME); 1832179193Sjb return (NULL); 1833179193Sjb } 1834179193Sjb 1835179193Sjb /* 1836179193Sjb * The highest stability class that fasttrap supports is ISA; cap 1837179193Sjb * the stability of the new provider accordingly. 1838179193Sjb */ 1839179193Sjb if (dhpv->dthpv_pattr.dtpa_provider.dtat_class > DTRACE_CLASS_ISA) 1840179193Sjb dhpv->dthpv_pattr.dtpa_provider.dtat_class = DTRACE_CLASS_ISA; 1841179193Sjb if (dhpv->dthpv_pattr.dtpa_mod.dtat_class > DTRACE_CLASS_ISA) 1842179193Sjb dhpv->dthpv_pattr.dtpa_mod.dtat_class = DTRACE_CLASS_ISA; 1843179193Sjb if (dhpv->dthpv_pattr.dtpa_func.dtat_class > DTRACE_CLASS_ISA) 1844179193Sjb dhpv->dthpv_pattr.dtpa_func.dtat_class = DTRACE_CLASS_ISA; 1845179193Sjb if (dhpv->dthpv_pattr.dtpa_name.dtat_class > DTRACE_CLASS_ISA) 1846179193Sjb dhpv->dthpv_pattr.dtpa_name.dtat_class = DTRACE_CLASS_ISA; 1847179193Sjb if (dhpv->dthpv_pattr.dtpa_args.dtat_class > DTRACE_CLASS_ISA) 1848179193Sjb dhpv->dthpv_pattr.dtpa_args.dtat_class = DTRACE_CLASS_ISA; 1849179193Sjb 1850179193Sjb if ((provider = fasttrap_provider_lookup(pid, dhpv->dthpv_provname, 1851179193Sjb &dhpv->dthpv_pattr)) == NULL) { 1852211738Srpaulo printf("failed to instantiate provider %s for " 1853179193Sjb "process %u", dhpv->dthpv_provname, (uint_t)pid); 1854179193Sjb return (NULL); 1855179193Sjb } 1856179193Sjb 1857179193Sjb /* 1858179193Sjb * Up the meta provider count so this provider isn't removed until 1859179193Sjb * the meta provider has been told to remove it. 1860179193Sjb */ 1861179193Sjb provider->ftp_mcount++; 1862179193Sjb 1863179193Sjb mutex_exit(&provider->ftp_mtx); 1864179193Sjb 1865179193Sjb return (provider); 1866179193Sjb} 1867179193Sjb 1868179193Sjb/*ARGSUSED*/ 1869179193Sjbstatic void 1870179193Sjbfasttrap_meta_create_probe(void *arg, void *parg, 1871179193Sjb dtrace_helper_probedesc_t *dhpb) 1872179193Sjb{ 1873179193Sjb fasttrap_provider_t *provider = parg; 1874179193Sjb fasttrap_probe_t *pp; 1875179193Sjb fasttrap_tracepoint_t *tp; 1876179193Sjb int i, j; 1877179193Sjb uint32_t ntps; 1878179193Sjb 1879179193Sjb /* 1880179193Sjb * Since the meta provider count is non-zero we don't have to worry 1881179193Sjb * about this provider disappearing. 1882179193Sjb */ 1883179193Sjb ASSERT(provider->ftp_mcount > 0); 1884179193Sjb 1885179193Sjb /* 1886179193Sjb * The offsets must be unique. 1887179193Sjb */ 1888179193Sjb qsort(dhpb->dthpb_offs, dhpb->dthpb_noffs, sizeof (uint32_t), 1889179193Sjb fasttrap_uint32_cmp); 1890179193Sjb for (i = 1; i < dhpb->dthpb_noffs; i++) { 1891179193Sjb if (dhpb->dthpb_base + dhpb->dthpb_offs[i] <= 1892179193Sjb dhpb->dthpb_base + dhpb->dthpb_offs[i - 1]) 1893179193Sjb return; 1894179193Sjb } 1895179193Sjb 1896179193Sjb qsort(dhpb->dthpb_enoffs, dhpb->dthpb_nenoffs, sizeof (uint32_t), 1897179193Sjb fasttrap_uint32_cmp); 1898179193Sjb for (i = 1; i < dhpb->dthpb_nenoffs; i++) { 1899179193Sjb if (dhpb->dthpb_base + dhpb->dthpb_enoffs[i] <= 1900179193Sjb dhpb->dthpb_base + dhpb->dthpb_enoffs[i - 1]) 1901179193Sjb return; 1902179193Sjb } 1903179193Sjb 1904179193Sjb /* 1905179193Sjb * Grab the creation lock to ensure consistency between calls to 1906179193Sjb * dtrace_probe_lookup() and dtrace_probe_create() in the face of 1907179193Sjb * other threads creating probes. 1908179193Sjb */ 1909179193Sjb mutex_enter(&provider->ftp_cmtx); 1910179193Sjb 1911179193Sjb if (dtrace_probe_lookup(provider->ftp_provid, dhpb->dthpb_mod, 1912179193Sjb dhpb->dthpb_func, dhpb->dthpb_name) != 0) { 1913179193Sjb mutex_exit(&provider->ftp_cmtx); 1914179193Sjb return; 1915179193Sjb } 1916179193Sjb 1917179193Sjb ntps = dhpb->dthpb_noffs + dhpb->dthpb_nenoffs; 1918179193Sjb ASSERT(ntps > 0); 1919179193Sjb 1920179193Sjb atomic_add_32(&fasttrap_total, ntps); 1921179193Sjb 1922179193Sjb if (fasttrap_total > fasttrap_max) { 1923179193Sjb atomic_add_32(&fasttrap_total, -ntps); 1924179193Sjb mutex_exit(&provider->ftp_cmtx); 1925179193Sjb return; 1926179193Sjb } 1927179193Sjb 1928179193Sjb pp = kmem_zalloc(offsetof(fasttrap_probe_t, ftp_tps[ntps]), KM_SLEEP); 1929179193Sjb 1930179193Sjb pp->ftp_prov = provider; 1931179193Sjb pp->ftp_pid = provider->ftp_pid; 1932179193Sjb pp->ftp_ntps = ntps; 1933179193Sjb pp->ftp_nargs = dhpb->dthpb_xargc; 1934179193Sjb pp->ftp_xtypes = dhpb->dthpb_xtypes; 1935179193Sjb pp->ftp_ntypes = dhpb->dthpb_ntypes; 1936179193Sjb 1937179193Sjb /* 1938179193Sjb * First create a tracepoint for each actual point of interest. 1939179193Sjb */ 1940179193Sjb for (i = 0; i < dhpb->dthpb_noffs; i++) { 1941179193Sjb tp = kmem_zalloc(sizeof (fasttrap_tracepoint_t), KM_SLEEP); 1942179193Sjb 1943179193Sjb tp->ftt_proc = provider->ftp_proc; 1944179193Sjb tp->ftt_pc = dhpb->dthpb_base + dhpb->dthpb_offs[i]; 1945179193Sjb tp->ftt_pid = provider->ftp_pid; 1946179193Sjb 1947179193Sjb pp->ftp_tps[i].fit_tp = tp; 1948179193Sjb pp->ftp_tps[i].fit_id.fti_probe = pp; 1949179193Sjb#ifdef __sparc 1950179193Sjb pp->ftp_tps[i].fit_id.fti_ptype = DTFTP_POST_OFFSETS; 1951179193Sjb#else 1952179193Sjb pp->ftp_tps[i].fit_id.fti_ptype = DTFTP_OFFSETS; 1953179193Sjb#endif 1954179193Sjb } 1955179193Sjb 1956179193Sjb /* 1957179193Sjb * Then create a tracepoint for each is-enabled point. 1958179193Sjb */ 1959179193Sjb for (j = 0; i < ntps; i++, j++) { 1960179193Sjb tp = kmem_zalloc(sizeof (fasttrap_tracepoint_t), KM_SLEEP); 1961179193Sjb 1962179193Sjb tp->ftt_proc = provider->ftp_proc; 1963179193Sjb tp->ftt_pc = dhpb->dthpb_base + dhpb->dthpb_enoffs[j]; 1964179193Sjb tp->ftt_pid = provider->ftp_pid; 1965179193Sjb 1966179193Sjb pp->ftp_tps[i].fit_tp = tp; 1967179193Sjb pp->ftp_tps[i].fit_id.fti_probe = pp; 1968179193Sjb pp->ftp_tps[i].fit_id.fti_ptype = DTFTP_IS_ENABLED; 1969179193Sjb } 1970179193Sjb 1971179193Sjb /* 1972179193Sjb * If the arguments are shuffled around we set the argument remapping 1973179193Sjb * table. Later, when the probe fires, we only remap the arguments 1974179193Sjb * if the table is non-NULL. 1975179193Sjb */ 1976179193Sjb for (i = 0; i < dhpb->dthpb_xargc; i++) { 1977179193Sjb if (dhpb->dthpb_args[i] != i) { 1978179193Sjb pp->ftp_argmap = dhpb->dthpb_args; 1979179193Sjb break; 1980179193Sjb } 1981179193Sjb } 1982179193Sjb 1983179193Sjb /* 1984179193Sjb * The probe is fully constructed -- register it with DTrace. 1985179193Sjb */ 1986179193Sjb pp->ftp_id = dtrace_probe_create(provider->ftp_provid, dhpb->dthpb_mod, 1987179193Sjb dhpb->dthpb_func, dhpb->dthpb_name, FASTTRAP_OFFSET_AFRAMES, pp); 1988179193Sjb 1989179193Sjb mutex_exit(&provider->ftp_cmtx); 1990179193Sjb} 1991179193Sjb 1992179193Sjb/*ARGSUSED*/ 1993179193Sjbstatic void 1994179193Sjbfasttrap_meta_remove(void *arg, dtrace_helper_provdesc_t *dhpv, pid_t pid) 1995179193Sjb{ 1996179193Sjb /* 1997179193Sjb * Clean up the USDT provider. There may be active consumers of the 1998179193Sjb * provider busy adding probes, no damage will actually befall the 1999179193Sjb * provider until that count has dropped to zero. This just puts 2000179193Sjb * the provider on death row. 2001179193Sjb */ 2002179193Sjb fasttrap_provider_retire(pid, dhpv->dthpv_provname, 1); 2003179193Sjb} 2004179193Sjb 2005179193Sjbstatic dtrace_mops_t fasttrap_mops = { 2006179193Sjb fasttrap_meta_create_probe, 2007179193Sjb fasttrap_meta_provide, 2008179193Sjb fasttrap_meta_remove 2009179193Sjb}; 2010179193Sjb 2011179193Sjb/*ARGSUSED*/ 2012179193Sjbstatic int 2013211738Srpaulofasttrap_open(struct cdev *dev __unused, int oflags __unused, 2014211738Srpaulo int devtype __unused, struct thread *td __unused) 2015179193Sjb{ 2016179193Sjb return (0); 2017179193Sjb} 2018179193Sjb 2019179193Sjb/*ARGSUSED*/ 2020179193Sjbstatic int 2021211738Srpaulofasttrap_ioctl(struct cdev *dev, u_long cmd, caddr_t arg, int fflag, 2022211738Srpaulo struct thread *td) 2023179193Sjb{ 2024211738Srpaulo#ifdef notyet 2025211738Srpaulo struct kinfo_proc kp; 2026211738Srpaulo const cred_t *cr = td->td_ucred; 2027211738Srpaulo#endif 2028179193Sjb if (!dtrace_attached()) 2029179193Sjb return (EAGAIN); 2030179193Sjb 2031179193Sjb if (cmd == FASTTRAPIOC_MAKEPROBE) { 2032179193Sjb fasttrap_probe_spec_t *uprobe = (void *)arg; 2033179193Sjb fasttrap_probe_spec_t *probe; 2034179193Sjb uint64_t noffs; 2035179193Sjb size_t size; 2036179193Sjb int ret; 2037179193Sjb char *c; 2038179193Sjb 2039211738Srpaulo#if defined(sun) 2040179193Sjb if (copyin(&uprobe->ftps_noffs, &noffs, 2041179193Sjb sizeof (uprobe->ftps_noffs))) 2042179193Sjb return (EFAULT); 2043211738Srpaulo#else 2044211738Srpaulo noffs = uprobe->ftps_noffs; 2045211738Srpaulo#endif 2046179193Sjb 2047179193Sjb /* 2048179193Sjb * Probes must have at least one tracepoint. 2049179193Sjb */ 2050179193Sjb if (noffs == 0) 2051179193Sjb return (EINVAL); 2052179193Sjb 2053179193Sjb size = sizeof (fasttrap_probe_spec_t) + 2054179193Sjb sizeof (probe->ftps_offs[0]) * (noffs - 1); 2055179193Sjb 2056179193Sjb if (size > 1024 * 1024) 2057179193Sjb return (ENOMEM); 2058179193Sjb 2059179193Sjb probe = kmem_alloc(size, KM_SLEEP); 2060179193Sjb 2061211738Srpaulo#if defined(sun) 2062179193Sjb if (copyin(uprobe, probe, size) != 0) { 2063179193Sjb kmem_free(probe, size); 2064179193Sjb return (EFAULT); 2065179193Sjb } 2066211738Srpaulo#else 2067211738Srpaulo memcpy(probe, uprobe, sizeof(*probe)); 2068211738Srpaulo if (noffs > 1 && copyin(uprobe + 1, probe + 1, size) != 0) { 2069211738Srpaulo kmem_free(probe, size); 2070211738Srpaulo return (EFAULT); 2071211738Srpaulo } 2072211738Srpaulo#endif 2073179193Sjb 2074211738Srpaulo 2075179193Sjb /* 2076179193Sjb * Verify that the function and module strings contain no 2077179193Sjb * funny characters. 2078179193Sjb */ 2079179193Sjb for (c = &probe->ftps_func[0]; *c != '\0'; c++) { 2080179193Sjb if (*c < 0x20 || 0x7f <= *c) { 2081179193Sjb ret = EINVAL; 2082179193Sjb goto err; 2083179193Sjb } 2084179193Sjb } 2085179193Sjb 2086179193Sjb for (c = &probe->ftps_mod[0]; *c != '\0'; c++) { 2087179193Sjb if (*c < 0x20 || 0x7f <= *c) { 2088179193Sjb ret = EINVAL; 2089179193Sjb goto err; 2090179193Sjb } 2091179193Sjb } 2092179193Sjb 2093211738Srpaulo#ifdef notyet 2094179193Sjb if (!PRIV_POLICY_CHOICE(cr, PRIV_ALL, B_FALSE)) { 2095179193Sjb proc_t *p; 2096179193Sjb pid_t pid = probe->ftps_pid; 2097179193Sjb 2098211738Srpaulo#if defined(sun) 2099179193Sjb mutex_enter(&pidlock); 2100211738Srpaulo#endif 2101179193Sjb /* 2102179193Sjb * Report an error if the process doesn't exist 2103179193Sjb * or is actively being birthed. 2104179193Sjb */ 2105211738Srpaulo p = pfind(pid); 2106211738Srpaulo if (p) 2107211738Srpaulo fill_kinfo_proc(p, &kp); 2108211738Srpaulo if (p == NULL || kp.ki_stat == SIDL) { 2109211738Srpaulo#if defined(sun) 2110179193Sjb mutex_exit(&pidlock); 2111211738Srpaulo#endif 2112179193Sjb return (ESRCH); 2113179193Sjb } 2114211738Srpaulo#if defined(sun) 2115179193Sjb mutex_enter(&p->p_lock); 2116179193Sjb mutex_exit(&pidlock); 2117211738Srpaulo#else 2118211738Srpaulo PROC_LOCK_ASSERT(p, MA_OWNED); 2119211738Srpaulo#endif 2120179193Sjb 2121211738Srpaulo#ifdef notyet 2122179193Sjb if ((ret = priv_proc_cred_perm(cr, p, NULL, 2123179193Sjb VREAD | VWRITE)) != 0) { 2124211738Srpaulo#if defined(sun) 2125179193Sjb mutex_exit(&p->p_lock); 2126211738Srpaulo#else 2127211738Srpaulo PROC_UNLOCK(p); 2128211738Srpaulo#endif 2129179193Sjb return (ret); 2130179193Sjb } 2131211738Srpaulo#endif /* notyet */ 2132211738Srpaulo#if defined(sun) 2133179193Sjb mutex_exit(&p->p_lock); 2134211738Srpaulo#else 2135211738Srpaulo PROC_UNLOCK(p); 2136211738Srpaulo#endif 2137179193Sjb } 2138211738Srpaulo#endif /* notyet */ 2139179193Sjb 2140179193Sjb ret = fasttrap_add_probe(probe); 2141179193Sjberr: 2142179193Sjb kmem_free(probe, size); 2143179193Sjb 2144179193Sjb return (ret); 2145179193Sjb 2146179193Sjb } else if (cmd == FASTTRAPIOC_GETINSTR) { 2147179193Sjb fasttrap_instr_query_t instr; 2148179193Sjb fasttrap_tracepoint_t *tp; 2149179193Sjb uint_t index; 2150211738Srpaulo#if defined(sun) 2151179193Sjb int ret; 2152211738Srpaulo#endif 2153179193Sjb 2154211738Srpaulo#if defined(sun) 2155179193Sjb if (copyin((void *)arg, &instr, sizeof (instr)) != 0) 2156179193Sjb return (EFAULT); 2157211738Srpaulo#endif 2158179193Sjb 2159211738Srpaulo#ifdef notyet 2160179193Sjb if (!PRIV_POLICY_CHOICE(cr, PRIV_ALL, B_FALSE)) { 2161179193Sjb proc_t *p; 2162179193Sjb pid_t pid = instr.ftiq_pid; 2163179193Sjb 2164211738Srpaulo#if defined(sun) 2165179193Sjb mutex_enter(&pidlock); 2166211738Srpaulo#endif 2167179193Sjb /* 2168179193Sjb * Report an error if the process doesn't exist 2169179193Sjb * or is actively being birthed. 2170179193Sjb */ 2171211738Srpaulo p = pfind(pid); 2172211738Srpaulo if (p) 2173211738Srpaulo fill_kinfo_proc(p, &kp); 2174211738Srpaulo if (p == NULL || kp.ki_stat == SIDL) { 2175211738Srpaulo#if defined(sun) 2176179193Sjb mutex_exit(&pidlock); 2177211738Srpaulo#endif 2178179193Sjb return (ESRCH); 2179179193Sjb } 2180211738Srpaulo#if defined(sun) 2181179193Sjb mutex_enter(&p->p_lock); 2182179193Sjb mutex_exit(&pidlock); 2183211738Srpaulo#else 2184211738Srpaulo PROC_LOCK_ASSERT(p, MA_OWNED); 2185211738Srpaulo#endif 2186179193Sjb 2187211738Srpaulo#ifdef notyet 2188179193Sjb if ((ret = priv_proc_cred_perm(cr, p, NULL, 2189179193Sjb VREAD)) != 0) { 2190211738Srpaulo#if defined(sun) 2191179193Sjb mutex_exit(&p->p_lock); 2192211738Srpaulo#else 2193211738Srpaulo PROC_UNLOCK(p); 2194211738Srpaulo#endif 2195179193Sjb return (ret); 2196179193Sjb } 2197211738Srpaulo#endif /* notyet */ 2198179193Sjb 2199211738Srpaulo#if defined(sun) 2200179193Sjb mutex_exit(&p->p_lock); 2201211738Srpaulo#else 2202211738Srpaulo PROC_UNLOCK(p); 2203211738Srpaulo#endif 2204179193Sjb } 2205211738Srpaulo#endif /* notyet */ 2206179193Sjb 2207179193Sjb index = FASTTRAP_TPOINTS_INDEX(instr.ftiq_pid, instr.ftiq_pc); 2208179193Sjb 2209179193Sjb mutex_enter(&fasttrap_tpoints.fth_table[index].ftb_mtx); 2210179193Sjb tp = fasttrap_tpoints.fth_table[index].ftb_data; 2211179193Sjb while (tp != NULL) { 2212179193Sjb if (instr.ftiq_pid == tp->ftt_pid && 2213179193Sjb instr.ftiq_pc == tp->ftt_pc && 2214179193Sjb tp->ftt_proc->ftpc_acount != 0) 2215179193Sjb break; 2216179193Sjb 2217179193Sjb tp = tp->ftt_next; 2218179193Sjb } 2219179193Sjb 2220179193Sjb if (tp == NULL) { 2221179193Sjb mutex_exit(&fasttrap_tpoints.fth_table[index].ftb_mtx); 2222179193Sjb return (ENOENT); 2223179193Sjb } 2224179193Sjb 2225179193Sjb bcopy(&tp->ftt_instr, &instr.ftiq_instr, 2226179193Sjb sizeof (instr.ftiq_instr)); 2227179193Sjb mutex_exit(&fasttrap_tpoints.fth_table[index].ftb_mtx); 2228179193Sjb 2229179193Sjb if (copyout(&instr, (void *)arg, sizeof (instr)) != 0) 2230179193Sjb return (EFAULT); 2231179193Sjb 2232179193Sjb return (0); 2233179193Sjb } 2234179193Sjb 2235179193Sjb return (EINVAL); 2236179193Sjb} 2237179193Sjb 2238179193Sjbstatic int 2239211738Srpaulofasttrap_load(void) 2240179193Sjb{ 2241179193Sjb ulong_t nent; 2242211738Srpaulo int i; 2243179193Sjb 2244211738Srpaulo /* Create the /dev/dtrace/fasttrap entry. */ 2245211738Srpaulo fasttrap_cdev = make_dev(&fasttrap_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600, 2246211738Srpaulo "dtrace/fasttrap"); 2247179193Sjb 2248211738Srpaulo mtx_init(&fasttrap_cleanup_mtx, "fasttrap clean", "dtrace", MTX_DEF); 2249211738Srpaulo callout_init_mtx(&fasttrap_timeout, &fasttrap_cleanup_mtx, 0); 2250211738Srpaulo mutex_init(&fasttrap_count_mtx, "fasttrap count mtx", MUTEX_DEFAULT, 2251211738Srpaulo NULL); 2252179193Sjb 2253179193Sjb /* 2254179193Sjb * Install our hooks into fork(2), exec(2), and exit(2). 2255179193Sjb */ 2256211738Srpaulo dtrace_fasttrap_fork = &fasttrap_fork; 2257211738Srpaulo dtrace_fasttrap_exit = &fasttrap_exec_exit; 2258211738Srpaulo dtrace_fasttrap_exec = &fasttrap_exec_exit; 2259179193Sjb 2260211738Srpaulo#if defined(sun) 2261179193Sjb fasttrap_max = ddi_getprop(DDI_DEV_T_ANY, devi, DDI_PROP_DONTPASS, 2262179193Sjb "fasttrap-max-probes", FASTTRAP_MAX_DEFAULT); 2263211738Srpaulo#else 2264211738Srpaulo fasttrap_max = FASTTRAP_MAX_DEFAULT; 2265211738Srpaulo#endif 2266179193Sjb fasttrap_total = 0; 2267179193Sjb 2268179193Sjb /* 2269179193Sjb * Conjure up the tracepoints hashtable... 2270179193Sjb */ 2271211738Srpaulo#if defined(sun) 2272179193Sjb nent = ddi_getprop(DDI_DEV_T_ANY, devi, DDI_PROP_DONTPASS, 2273179193Sjb "fasttrap-hash-size", FASTTRAP_TPOINTS_DEFAULT_SIZE); 2274211738Srpaulo#else 2275211738Srpaulo nent = FASTTRAP_TPOINTS_DEFAULT_SIZE; 2276211738Srpaulo#endif 2277179193Sjb 2278179193Sjb if (nent == 0 || nent > 0x1000000) 2279179193Sjb nent = FASTTRAP_TPOINTS_DEFAULT_SIZE; 2280179193Sjb 2281179193Sjb if ((nent & (nent - 1)) == 0) 2282179193Sjb fasttrap_tpoints.fth_nent = nent; 2283179193Sjb else 2284179193Sjb fasttrap_tpoints.fth_nent = 1 << fasttrap_highbit(nent); 2285179193Sjb ASSERT(fasttrap_tpoints.fth_nent > 0); 2286179193Sjb fasttrap_tpoints.fth_mask = fasttrap_tpoints.fth_nent - 1; 2287179193Sjb fasttrap_tpoints.fth_table = kmem_zalloc(fasttrap_tpoints.fth_nent * 2288179193Sjb sizeof (fasttrap_bucket_t), KM_SLEEP); 2289211738Srpaulo#if !defined(sun) 2290211738Srpaulo for (i = 0; i < fasttrap_tpoints.fth_nent; i++) 2291211738Srpaulo mutex_init(&fasttrap_tpoints.fth_table[i].ftb_mtx, 2292211738Srpaulo "tracepoints bucket mtx", MUTEX_DEFAULT, NULL); 2293211738Srpaulo#endif 2294179193Sjb 2295179193Sjb /* 2296179193Sjb * ... and the providers hash table... 2297179193Sjb */ 2298179193Sjb nent = FASTTRAP_PROVIDERS_DEFAULT_SIZE; 2299179193Sjb if ((nent & (nent - 1)) == 0) 2300179193Sjb fasttrap_provs.fth_nent = nent; 2301179193Sjb else 2302179193Sjb fasttrap_provs.fth_nent = 1 << fasttrap_highbit(nent); 2303179193Sjb ASSERT(fasttrap_provs.fth_nent > 0); 2304179193Sjb fasttrap_provs.fth_mask = fasttrap_provs.fth_nent - 1; 2305179193Sjb fasttrap_provs.fth_table = kmem_zalloc(fasttrap_provs.fth_nent * 2306179193Sjb sizeof (fasttrap_bucket_t), KM_SLEEP); 2307211738Srpaulo#if !defined(sun) 2308211738Srpaulo for (i = 0; i < fasttrap_provs.fth_nent; i++) 2309211738Srpaulo mutex_init(&fasttrap_provs.fth_table[i].ftb_mtx, 2310211738Srpaulo "providers bucket mtx", MUTEX_DEFAULT, NULL); 2311211738Srpaulo#endif 2312179193Sjb 2313179193Sjb /* 2314179193Sjb * ... and the procs hash table. 2315179193Sjb */ 2316179193Sjb nent = FASTTRAP_PROCS_DEFAULT_SIZE; 2317179193Sjb if ((nent & (nent - 1)) == 0) 2318179193Sjb fasttrap_procs.fth_nent = nent; 2319179193Sjb else 2320179193Sjb fasttrap_procs.fth_nent = 1 << fasttrap_highbit(nent); 2321179193Sjb ASSERT(fasttrap_procs.fth_nent > 0); 2322179193Sjb fasttrap_procs.fth_mask = fasttrap_procs.fth_nent - 1; 2323179193Sjb fasttrap_procs.fth_table = kmem_zalloc(fasttrap_procs.fth_nent * 2324179193Sjb sizeof (fasttrap_bucket_t), KM_SLEEP); 2325211738Srpaulo#if !defined(sun) 2326211738Srpaulo for (i = 0; i < fasttrap_procs.fth_nent; i++) 2327211738Srpaulo mutex_init(&fasttrap_procs.fth_table[i].ftb_mtx, 2328211738Srpaulo "processes bucket mtx", MUTEX_DEFAULT, NULL); 2329211738Srpaulo#endif 2330179193Sjb 2331179193Sjb (void) dtrace_meta_register("fasttrap", &fasttrap_mops, NULL, 2332179193Sjb &fasttrap_meta_id); 2333179193Sjb 2334211738Srpaulo return (0); 2335179193Sjb} 2336179193Sjb 2337179193Sjbstatic int 2338211738Srpaulofasttrap_unload(void) 2339179193Sjb{ 2340179193Sjb int i, fail = 0; 2341179193Sjb 2342179193Sjb /* 2343179193Sjb * Unregister the meta-provider to make sure no new fasttrap- 2344179193Sjb * managed providers come along while we're trying to close up 2345179193Sjb * shop. If we fail to detach, we'll need to re-register as a 2346179193Sjb * meta-provider. We can fail to unregister as a meta-provider 2347179193Sjb * if providers we manage still exist. 2348179193Sjb */ 2349179193Sjb if (fasttrap_meta_id != DTRACE_METAPROVNONE && 2350179193Sjb dtrace_meta_unregister(fasttrap_meta_id) != 0) 2351211738Srpaulo return (-1); 2352179193Sjb 2353179193Sjb /* 2354179193Sjb * Prevent any new timeouts from running by setting fasttrap_timeout 2355179193Sjb * to a non-zero value, and wait for the current timeout to complete. 2356179193Sjb */ 2357211738Srpaulo mtx_lock(&fasttrap_cleanup_mtx); 2358179193Sjb fasttrap_cleanup_work = 0; 2359211738Srpaulo callout_drain(&fasttrap_timeout); 2360211738Srpaulo mtx_unlock(&fasttrap_cleanup_mtx); 2361179193Sjb 2362179193Sjb /* 2363179193Sjb * Iterate over all of our providers. If there's still a process 2364179193Sjb * that corresponds to that pid, fail to detach. 2365179193Sjb */ 2366179193Sjb for (i = 0; i < fasttrap_provs.fth_nent; i++) { 2367179193Sjb fasttrap_provider_t **fpp, *fp; 2368179193Sjb fasttrap_bucket_t *bucket = &fasttrap_provs.fth_table[i]; 2369179193Sjb 2370179193Sjb mutex_enter(&bucket->ftb_mtx); 2371179193Sjb fpp = (fasttrap_provider_t **)&bucket->ftb_data; 2372179193Sjb while ((fp = *fpp) != NULL) { 2373179193Sjb /* 2374179193Sjb * Acquire and release the lock as a simple way of 2375179193Sjb * waiting for any other consumer to finish with 2376179193Sjb * this provider. A thread must first acquire the 2377179193Sjb * bucket lock so there's no chance of another thread 2378179193Sjb * blocking on the provider's lock. 2379179193Sjb */ 2380179193Sjb mutex_enter(&fp->ftp_mtx); 2381179193Sjb mutex_exit(&fp->ftp_mtx); 2382179193Sjb 2383179193Sjb if (dtrace_unregister(fp->ftp_provid) != 0) { 2384179193Sjb fail = 1; 2385179193Sjb fpp = &fp->ftp_next; 2386179193Sjb } else { 2387179193Sjb *fpp = fp->ftp_next; 2388179193Sjb fasttrap_provider_free(fp); 2389179193Sjb } 2390179193Sjb } 2391179193Sjb 2392179193Sjb mutex_exit(&bucket->ftb_mtx); 2393179193Sjb } 2394179193Sjb 2395179193Sjb if (fail) { 2396179193Sjb uint_t work; 2397179193Sjb /* 2398179193Sjb * If we're failing to detach, we need to unblock timeouts 2399179193Sjb * and start a new timeout if any work has accumulated while 2400179193Sjb * we've been unsuccessfully trying to detach. 2401179193Sjb */ 2402211738Srpaulo mtx_lock(&fasttrap_cleanup_mtx); 2403179193Sjb work = fasttrap_cleanup_work; 2404211738Srpaulo callout_drain(&fasttrap_timeout); 2405211738Srpaulo mtx_unlock(&fasttrap_cleanup_mtx); 2406179193Sjb 2407179193Sjb if (work) 2408179193Sjb fasttrap_pid_cleanup(); 2409179193Sjb 2410179193Sjb (void) dtrace_meta_register("fasttrap", &fasttrap_mops, NULL, 2411179193Sjb &fasttrap_meta_id); 2412179193Sjb 2413211738Srpaulo return (-1); 2414179193Sjb } 2415179193Sjb 2416179193Sjb#ifdef DEBUG 2417179193Sjb mutex_enter(&fasttrap_count_mtx); 2418179193Sjb ASSERT(fasttrap_pid_count == 0); 2419179193Sjb mutex_exit(&fasttrap_count_mtx); 2420179193Sjb#endif 2421179193Sjb 2422179193Sjb kmem_free(fasttrap_tpoints.fth_table, 2423179193Sjb fasttrap_tpoints.fth_nent * sizeof (fasttrap_bucket_t)); 2424179193Sjb fasttrap_tpoints.fth_nent = 0; 2425179193Sjb 2426179193Sjb kmem_free(fasttrap_provs.fth_table, 2427179193Sjb fasttrap_provs.fth_nent * sizeof (fasttrap_bucket_t)); 2428179193Sjb fasttrap_provs.fth_nent = 0; 2429179193Sjb 2430179193Sjb kmem_free(fasttrap_procs.fth_table, 2431179193Sjb fasttrap_procs.fth_nent * sizeof (fasttrap_bucket_t)); 2432179193Sjb fasttrap_procs.fth_nent = 0; 2433179193Sjb 2434179193Sjb /* 2435179193Sjb * We know there are no tracepoints in any process anywhere in 2436179193Sjb * the system so there is no process which has its p_dtrace_count 2437179193Sjb * greater than zero, therefore we know that no thread can actively 2438179193Sjb * be executing code in fasttrap_fork(). Similarly for p_dtrace_probes 2439179193Sjb * and fasttrap_exec() and fasttrap_exit(). 2440179193Sjb */ 2441211738Srpaulo ASSERT(dtrace_fasttrap_fork == &fasttrap_fork); 2442211738Srpaulo dtrace_fasttrap_fork = NULL; 2443179193Sjb 2444211738Srpaulo ASSERT(dtrace_fasttrap_exec == &fasttrap_exec_exit); 2445211738Srpaulo dtrace_fasttrap_exec = NULL; 2446179193Sjb 2447211738Srpaulo ASSERT(dtrace_fasttrap_exit == &fasttrap_exec_exit); 2448211738Srpaulo dtrace_fasttrap_exit = NULL; 2449179193Sjb 2450211738Srpaulo#if !defined(sun) 2451211738Srpaulo destroy_dev(fasttrap_cdev); 2452211738Srpaulo mutex_destroy(&fasttrap_count_mtx); 2453211738Srpaulo#endif 2454179193Sjb 2455211738Srpaulo return (0); 2456179193Sjb} 2457179193Sjb 2458211738Srpaulo/* ARGSUSED */ 2459211738Srpaulostatic int 2460211738Srpaulofasttrap_modevent(module_t mod __unused, int type, void *data __unused) 2461211738Srpaulo{ 2462211738Srpaulo int error = 0; 2463179193Sjb 2464211738Srpaulo switch (type) { 2465211738Srpaulo case MOD_LOAD: 2466211738Srpaulo break; 2467179193Sjb 2468211738Srpaulo case MOD_UNLOAD: 2469211738Srpaulo break; 2470179193Sjb 2471211738Srpaulo case MOD_SHUTDOWN: 2472211738Srpaulo break; 2473179193Sjb 2474211738Srpaulo default: 2475211738Srpaulo error = EOPNOTSUPP; 2476211738Srpaulo break; 2477211738Srpaulo } 2478211738Srpaulo return (error); 2479179193Sjb} 2480179193Sjb 2481211738SrpauloSYSINIT(fasttrap_load, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY, fasttrap_load, 2482211738Srpaulo NULL); 2483211738SrpauloSYSUNINIT(fasttrap_unload, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY, 2484211738Srpaulo fasttrap_unload, NULL); 2485211738Srpaulo 2486211738SrpauloDEV_MODULE(fasttrap, fasttrap_modevent, NULL); 2487211738SrpauloMODULE_VERSION(fasttrap, 1); 2488211738SrpauloMODULE_DEPEND(fasttrap, dtrace, 1, 1, 1); 2489211738SrpauloMODULE_DEPEND(fasttrap, opensolaris, 1, 1, 1); 2490