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 * $FreeBSD$ 24179193Sjb */ 25179193Sjb 26179193Sjb/* 27179198Sjb * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 28179193Sjb * Use is subject to license terms. 29179193Sjb */ 30179193Sjb 31268734Spfg/* 32268734Spfg * Copyright (c) 2013, Joyent, Inc. All rights reserved. 33268734Spfg */ 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> 41297077Smav#ifdef illumos 42179193Sjb#include <sys/ddi.h> 43211738Srpaulo#endif 44179193Sjb#include <sys/sunddi.h> 45179193Sjb#include <sys/cpuvar.h> 46179193Sjb#include <sys/kmem.h> 47297077Smav#ifdef illumos 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> 58297077Smav#ifdef illumos 59179193Sjb#include <util/qsort.h> 60211738Srpaulo#endif 61211738Srpaulo#include <sys/mutex.h> 62211738Srpaulo#include <sys/kernel.h> 63297077Smav#ifndef illumos 64269342Smarkj#include <sys/dtrace_bsd.h> 65269342Smarkj#include <sys/eventhandler.h> 66299003Smarkj#include <sys/rmlock.h> 67293413Sstas#include <sys/sysctl.h> 68293413Sstas#include <sys/u8_textprep.h> 69211738Srpaulo#include <sys/user.h> 70299003Smarkj 71269342Smarkj#include <vm/vm.h> 72269342Smarkj#include <vm/pmap.h> 73269342Smarkj#include <vm/vm_map.h> 74269342Smarkj#include <vm/vm_param.h> 75299003Smarkj 76211738Srpaulo#include <cddl/dev/dtrace/dtrace_cddl.h> 77211738Srpaulo#endif 78179193Sjb 79179193Sjb/* 80179193Sjb * User-Land Trap-Based Tracing 81179193Sjb * ---------------------------- 82179193Sjb * 83179193Sjb * The fasttrap provider allows DTrace consumers to instrument any user-level 84179193Sjb * instruction to gather data; this includes probes with semantic 85179193Sjb * signifigance like entry and return as well as simple offsets into the 86179193Sjb * function. While the specific techniques used are very ISA specific, the 87179193Sjb * methodology is generalizable to any architecture. 88179193Sjb * 89179193Sjb * 90179193Sjb * The General Methodology 91179193Sjb * ----------------------- 92179193Sjb * 93179193Sjb * With the primary goal of tracing every user-land instruction and the 94179193Sjb * limitation that we can't trust user space so don't want to rely on much 95179193Sjb * information there, we begin by replacing the instructions we want to trace 96179193Sjb * with trap instructions. Each instruction we overwrite is saved into a hash 97179193Sjb * table keyed by process ID and pc address. When we enter the kernel due to 98179193Sjb * this trap instruction, we need the effects of the replaced instruction to 99179193Sjb * appear to have occurred before we proceed with the user thread's 100179193Sjb * execution. 101179193Sjb * 102179193Sjb * Each user level thread is represented by a ulwp_t structure which is 103179193Sjb * always easily accessible through a register. The most basic way to produce 104179193Sjb * the effects of the instruction we replaced is to copy that instruction out 105179193Sjb * to a bit of scratch space reserved in the user thread's ulwp_t structure 106179193Sjb * (a sort of kernel-private thread local storage), set the PC to that 107179193Sjb * scratch space and single step. When we reenter the kernel after single 108179193Sjb * stepping the instruction we must then adjust the PC to point to what would 109179193Sjb * normally be the next instruction. Of course, special care must be taken 110179193Sjb * for branches and jumps, but these represent such a small fraction of any 111179193Sjb * instruction set that writing the code to emulate these in the kernel is 112179193Sjb * not too difficult. 113179193Sjb * 114179193Sjb * Return probes may require several tracepoints to trace every return site, 115179193Sjb * and, conversely, each tracepoint may activate several probes (the entry 116179193Sjb * and offset 0 probes, for example). To solve this muliplexing problem, 117179193Sjb * tracepoints contain lists of probes to activate and probes contain lists 118179193Sjb * of tracepoints to enable. If a probe is activated, it adds its ID to 119179193Sjb * existing tracepoints or creates new ones as necessary. 120179193Sjb * 121179193Sjb * Most probes are activated _before_ the instruction is executed, but return 122179193Sjb * probes are activated _after_ the effects of the last instruction of the 123179193Sjb * function are visible. Return probes must be fired _after_ we have 124179193Sjb * single-stepped the instruction whereas all other probes are fired 125179193Sjb * beforehand. 126179193Sjb * 127179193Sjb * 128179193Sjb * Lock Ordering 129179193Sjb * ------------- 130179193Sjb * 131179193Sjb * The lock ordering below -- both internally and with respect to the DTrace 132179193Sjb * framework -- is a little tricky and bears some explanation. Each provider 133179193Sjb * has a lock (ftp_mtx) that protects its members including reference counts 134179193Sjb * for enabled probes (ftp_rcount), consumers actively creating probes 135179193Sjb * (ftp_ccount) and USDT consumers (ftp_mcount); all three prevent a provider 136179193Sjb * from being freed. A provider is looked up by taking the bucket lock for the 137179193Sjb * provider hash table, and is returned with its lock held. The provider lock 138179193Sjb * may be taken in functions invoked by the DTrace framework, but may not be 139179193Sjb * held while calling functions in the DTrace framework. 140179193Sjb * 141179193Sjb * To ensure consistency over multiple calls to the DTrace framework, the 142179193Sjb * creation lock (ftp_cmtx) should be held. Naturally, the creation lock may 143179193Sjb * not be taken when holding the provider lock as that would create a cyclic 144179193Sjb * lock ordering. In situations where one would naturally take the provider 145179193Sjb * lock and then the creation lock, we instead up a reference count to prevent 146179193Sjb * the provider from disappearing, drop the provider lock, and acquire the 147179193Sjb * creation lock. 148179193Sjb * 149179193Sjb * Briefly: 150179193Sjb * bucket lock before provider lock 151179193Sjb * DTrace before provider lock 152179193Sjb * creation lock before DTrace 153179193Sjb * never hold the provider lock and creation lock simultaneously 154179193Sjb */ 155179193Sjb 156211738Srpaulostatic d_open_t fasttrap_open; 157211738Srpaulostatic d_ioctl_t fasttrap_ioctl; 158211738Srpaulo 159211738Srpaulostatic struct cdevsw fasttrap_cdevsw = { 160211738Srpaulo .d_version = D_VERSION, 161211738Srpaulo .d_open = fasttrap_open, 162211738Srpaulo .d_ioctl = fasttrap_ioctl, 163211738Srpaulo .d_name = "fasttrap", 164211738Srpaulo}; 165211738Srpaulostatic struct cdev *fasttrap_cdev; 166179193Sjbstatic dtrace_meta_provider_id_t fasttrap_meta_id; 167179193Sjb 168250953Smarkjstatic struct proc *fasttrap_cleanup_proc; 169211738Srpaulostatic struct mtx fasttrap_cleanup_mtx; 170250953Smarkjstatic uint_t fasttrap_cleanup_work, fasttrap_cleanup_drain, fasttrap_cleanup_cv; 171179193Sjb 172179193Sjb/* 173179193Sjb * Generation count on modifications to the global tracepoint lookup table. 174179193Sjb */ 175179193Sjbstatic volatile uint64_t fasttrap_mod_gen; 176179193Sjb 177179193Sjb/* 178179193Sjb * When the fasttrap provider is loaded, fasttrap_max is set to either 179293413Sstas * FASTTRAP_MAX_DEFAULT, or the value for fasttrap-max-probes in the 180293413Sstas * fasttrap.conf file (Illumos), or the value provied in the loader.conf (FreeBSD). 181293413Sstas * Each time a probe is created, fasttrap_total is incremented by the number 182293413Sstas * of tracepoints that may be associated with that probe; fasttrap_total is capped 183293413Sstas * at fasttrap_max. 184179193Sjb */ 185179193Sjb#define FASTTRAP_MAX_DEFAULT 250000 186293413Sstasstatic uint32_t fasttrap_max = FASTTRAP_MAX_DEFAULT; 187179193Sjbstatic uint32_t fasttrap_total; 188179193Sjb 189248983Spfg/* 190248983Spfg * Copyright (c) 2011, Joyent, Inc. All rights reserved. 191248983Spfg */ 192179193Sjb 193179193Sjb#define FASTTRAP_TPOINTS_DEFAULT_SIZE 0x4000 194179193Sjb#define FASTTRAP_PROVIDERS_DEFAULT_SIZE 0x100 195179193Sjb#define FASTTRAP_PROCS_DEFAULT_SIZE 0x100 196179193Sjb 197179193Sjb#define FASTTRAP_PID_NAME "pid" 198179193Sjb 199179193Sjbfasttrap_hash_t fasttrap_tpoints; 200179193Sjbstatic fasttrap_hash_t fasttrap_provs; 201179193Sjbstatic fasttrap_hash_t fasttrap_procs; 202179193Sjb 203179193Sjbstatic uint64_t fasttrap_pid_count; /* pid ref count */ 204179193Sjbstatic kmutex_t fasttrap_count_mtx; /* lock on ref count */ 205179193Sjb 206179193Sjb#define FASTTRAP_ENABLE_FAIL 1 207179193Sjb#define FASTTRAP_ENABLE_PARTIAL 2 208179193Sjb 209179193Sjbstatic int fasttrap_tracepoint_enable(proc_t *, fasttrap_probe_t *, uint_t); 210179193Sjbstatic void fasttrap_tracepoint_disable(proc_t *, fasttrap_probe_t *, uint_t); 211179193Sjb 212179193Sjbstatic fasttrap_provider_t *fasttrap_provider_lookup(pid_t, const char *, 213179193Sjb const dtrace_pattr_t *); 214179193Sjbstatic void fasttrap_provider_retire(pid_t, const char *, int); 215179193Sjbstatic void fasttrap_provider_free(fasttrap_provider_t *); 216179193Sjb 217179193Sjbstatic fasttrap_proc_t *fasttrap_proc_lookup(pid_t); 218179193Sjbstatic void fasttrap_proc_release(fasttrap_proc_t *); 219179193Sjb 220297077Smav#ifndef illumos 221269342Smarkjstatic void fasttrap_thread_dtor(void *, struct thread *); 222269342Smarkj#endif 223269342Smarkj 224179193Sjb#define FASTTRAP_PROVS_INDEX(pid, name) \ 225179193Sjb ((fasttrap_hash_str(name) + (pid)) & fasttrap_provs.fth_mask) 226179193Sjb 227179193Sjb#define FASTTRAP_PROCS_INDEX(pid) ((pid) & fasttrap_procs.fth_mask) 228179193Sjb 229297077Smav#ifndef illumos 230299003Smarkjstruct rmlock fasttrap_tp_lock; 231269342Smarkjstatic eventhandler_tag fasttrap_thread_dtor_tag; 232211925Srpaulo#endif 233211925Srpaulo 234293413Sstasstatic unsigned long tpoints_hash_size = FASTTRAP_TPOINTS_DEFAULT_SIZE; 235293413Sstas 236293413Sstas#ifdef __FreeBSD__ 237293413SstasSYSCTL_DECL(_kern_dtrace); 238293413SstasSYSCTL_NODE(_kern_dtrace, OID_AUTO, fasttrap, CTLFLAG_RD, 0, "DTrace fasttrap parameters"); 239293413SstasSYSCTL_UINT(_kern_dtrace_fasttrap, OID_AUTO, max_probes, CTLFLAG_RWTUN, &fasttrap_max, 240293413Sstas FASTTRAP_MAX_DEFAULT, "Maximum number of fasttrap probes"); 241293413SstasSYSCTL_ULONG(_kern_dtrace_fasttrap, OID_AUTO, tpoints_hash_size, CTLFLAG_RDTUN, &tpoints_hash_size, 242293413Sstas FASTTRAP_TPOINTS_DEFAULT_SIZE, "Size of the tracepoint hash table"); 243293413Sstas#endif 244293413Sstas 245179193Sjbstatic int 246179193Sjbfasttrap_highbit(ulong_t i) 247179193Sjb{ 248179193Sjb int h = 1; 249179193Sjb 250179193Sjb if (i == 0) 251179193Sjb return (0); 252179193Sjb#ifdef _LP64 253179193Sjb if (i & 0xffffffff00000000ul) { 254179193Sjb h += 32; i >>= 32; 255179193Sjb } 256179193Sjb#endif 257179193Sjb if (i & 0xffff0000) { 258179193Sjb h += 16; i >>= 16; 259179193Sjb } 260179193Sjb if (i & 0xff00) { 261179193Sjb h += 8; i >>= 8; 262179193Sjb } 263179193Sjb if (i & 0xf0) { 264179193Sjb h += 4; i >>= 4; 265179193Sjb } 266179193Sjb if (i & 0xc) { 267179193Sjb h += 2; i >>= 2; 268179193Sjb } 269179193Sjb if (i & 0x2) { 270179193Sjb h += 1; 271179193Sjb } 272179193Sjb return (h); 273179193Sjb} 274179193Sjb 275179193Sjbstatic uint_t 276179193Sjbfasttrap_hash_str(const char *p) 277179193Sjb{ 278179193Sjb unsigned int g; 279179193Sjb uint_t hval = 0; 280179193Sjb 281179193Sjb while (*p) { 282179193Sjb hval = (hval << 4) + *p++; 283179193Sjb if ((g = (hval & 0xf0000000)) != 0) 284179193Sjb hval ^= g >> 24; 285179193Sjb hval &= ~g; 286179193Sjb } 287179193Sjb return (hval); 288179193Sjb} 289179193Sjb 290179193Sjbvoid 291179193Sjbfasttrap_sigtrap(proc_t *p, kthread_t *t, uintptr_t pc) 292179193Sjb{ 293297077Smav#ifdef illumos 294179193Sjb sigqueue_t *sqp = kmem_zalloc(sizeof (sigqueue_t), KM_SLEEP); 295179193Sjb 296179193Sjb sqp->sq_info.si_signo = SIGTRAP; 297179193Sjb sqp->sq_info.si_code = TRAP_DTRACE; 298179193Sjb sqp->sq_info.si_addr = (caddr_t)pc; 299179193Sjb 300179193Sjb mutex_enter(&p->p_lock); 301179193Sjb sigaddqa(p, t, sqp); 302179193Sjb mutex_exit(&p->p_lock); 303179193Sjb 304179193Sjb if (t != NULL) 305179193Sjb aston(t); 306211738Srpaulo#else 307211738Srpaulo ksiginfo_t *ksi = kmem_zalloc(sizeof (ksiginfo_t), KM_SLEEP); 308211738Srpaulo 309211738Srpaulo ksiginfo_init(ksi); 310211738Srpaulo ksi->ksi_signo = SIGTRAP; 311211738Srpaulo ksi->ksi_code = TRAP_DTRACE; 312211738Srpaulo ksi->ksi_addr = (caddr_t)pc; 313211738Srpaulo PROC_LOCK(p); 314283677Smarkj (void) tdsendsignal(p, t, SIGTRAP, ksi); 315211738Srpaulo PROC_UNLOCK(p); 316211738Srpaulo#endif 317179193Sjb} 318179193Sjb 319297077Smav#ifndef illumos 320179193Sjb/* 321269342Smarkj * Obtain a chunk of scratch space in the address space of the target process. 322269342Smarkj */ 323269342Smarkjfasttrap_scrspace_t * 324269342Smarkjfasttrap_scraddr(struct thread *td, fasttrap_proc_t *fprc) 325269342Smarkj{ 326269342Smarkj fasttrap_scrblock_t *scrblk; 327269342Smarkj fasttrap_scrspace_t *scrspc; 328269342Smarkj struct proc *p; 329269342Smarkj vm_offset_t addr; 330269342Smarkj int error, i; 331269342Smarkj 332269342Smarkj scrspc = NULL; 333269342Smarkj if (td->t_dtrace_sscr != NULL) { 334269342Smarkj /* If the thread already has scratch space, we're done. */ 335269342Smarkj scrspc = (fasttrap_scrspace_t *)td->t_dtrace_sscr; 336269342Smarkj return (scrspc); 337269342Smarkj } 338269342Smarkj 339269342Smarkj p = td->td_proc; 340269342Smarkj 341269342Smarkj mutex_enter(&fprc->ftpc_mtx); 342269342Smarkj if (LIST_EMPTY(&fprc->ftpc_fscr)) { 343269342Smarkj /* 344269342Smarkj * No scratch space is available, so we'll map a new scratch 345269342Smarkj * space block into the traced process' address space. 346269342Smarkj */ 347269342Smarkj addr = 0; 348269342Smarkj error = vm_map_find(&p->p_vmspace->vm_map, NULL, 0, &addr, 349269342Smarkj FASTTRAP_SCRBLOCK_SIZE, 0, VMFS_ANY_SPACE, VM_PROT_ALL, 350269342Smarkj VM_PROT_ALL, 0); 351269342Smarkj if (error != KERN_SUCCESS) 352269342Smarkj goto done; 353269342Smarkj 354269342Smarkj scrblk = malloc(sizeof(*scrblk), M_SOLARIS, M_WAITOK); 355269342Smarkj scrblk->ftsb_addr = addr; 356269342Smarkj LIST_INSERT_HEAD(&fprc->ftpc_scrblks, scrblk, ftsb_next); 357269342Smarkj 358269342Smarkj /* 359269342Smarkj * Carve the block up into chunks and put them on the free list. 360269342Smarkj */ 361269342Smarkj for (i = 0; 362269342Smarkj i < FASTTRAP_SCRBLOCK_SIZE / FASTTRAP_SCRSPACE_SIZE; i++) { 363269342Smarkj scrspc = malloc(sizeof(*scrspc), M_SOLARIS, M_WAITOK); 364269342Smarkj scrspc->ftss_addr = addr + 365269342Smarkj i * FASTTRAP_SCRSPACE_SIZE; 366269342Smarkj LIST_INSERT_HEAD(&fprc->ftpc_fscr, scrspc, 367269342Smarkj ftss_next); 368269342Smarkj } 369269342Smarkj } 370269342Smarkj 371269342Smarkj /* 372269342Smarkj * Take the first scratch chunk off the free list, put it on the 373269342Smarkj * allocated list, and return its address. 374269342Smarkj */ 375269342Smarkj scrspc = LIST_FIRST(&fprc->ftpc_fscr); 376269342Smarkj LIST_REMOVE(scrspc, ftss_next); 377269342Smarkj LIST_INSERT_HEAD(&fprc->ftpc_ascr, scrspc, ftss_next); 378269342Smarkj 379269342Smarkj /* 380269342Smarkj * This scratch space is reserved for use by td until the thread exits. 381269342Smarkj */ 382269342Smarkj td->t_dtrace_sscr = scrspc; 383269342Smarkj 384269342Smarkjdone: 385269342Smarkj mutex_exit(&fprc->ftpc_mtx); 386269342Smarkj 387269342Smarkj return (scrspc); 388269342Smarkj} 389269342Smarkj 390269342Smarkj/* 391269342Smarkj * Return any allocated per-thread scratch space chunks back to the process' 392269342Smarkj * free list. 393269342Smarkj */ 394269342Smarkjstatic void 395269342Smarkjfasttrap_thread_dtor(void *arg __unused, struct thread *td) 396269342Smarkj{ 397269342Smarkj fasttrap_bucket_t *bucket; 398269342Smarkj fasttrap_proc_t *fprc; 399269342Smarkj fasttrap_scrspace_t *scrspc; 400269342Smarkj pid_t pid; 401269342Smarkj 402269342Smarkj if (td->t_dtrace_sscr == NULL) 403269342Smarkj return; 404269342Smarkj 405269342Smarkj pid = td->td_proc->p_pid; 406269342Smarkj bucket = &fasttrap_procs.fth_table[FASTTRAP_PROCS_INDEX(pid)]; 407269342Smarkj fprc = NULL; 408269342Smarkj 409269342Smarkj /* Look up the fasttrap process handle for this process. */ 410269342Smarkj mutex_enter(&bucket->ftb_mtx); 411269342Smarkj for (fprc = bucket->ftb_data; fprc != NULL; fprc = fprc->ftpc_next) { 412269342Smarkj if (fprc->ftpc_pid == pid) { 413269342Smarkj mutex_enter(&fprc->ftpc_mtx); 414269342Smarkj mutex_exit(&bucket->ftb_mtx); 415269342Smarkj break; 416269342Smarkj } 417269342Smarkj } 418269342Smarkj if (fprc == NULL) { 419269342Smarkj mutex_exit(&bucket->ftb_mtx); 420269342Smarkj return; 421269342Smarkj } 422269342Smarkj 423269342Smarkj scrspc = (fasttrap_scrspace_t *)td->t_dtrace_sscr; 424269342Smarkj LIST_REMOVE(scrspc, ftss_next); 425269342Smarkj LIST_INSERT_HEAD(&fprc->ftpc_fscr, scrspc, ftss_next); 426269342Smarkj 427269342Smarkj mutex_exit(&fprc->ftpc_mtx); 428269342Smarkj} 429269342Smarkj#endif 430269342Smarkj 431269342Smarkj/* 432179193Sjb * This function ensures that no threads are actively using the memory 433179193Sjb * associated with probes that were formerly live. 434179193Sjb */ 435179193Sjbstatic void 436179193Sjbfasttrap_mod_barrier(uint64_t gen) 437179193Sjb{ 438179193Sjb int i; 439179193Sjb 440179193Sjb if (gen < fasttrap_mod_gen) 441179193Sjb return; 442179193Sjb 443179193Sjb fasttrap_mod_gen++; 444179193Sjb 445299003Smarkj#ifdef illumos 446211925Srpaulo CPU_FOREACH(i) { 447211925Srpaulo mutex_enter(&fasttrap_cpuc_pid_lock[i]); 448211925Srpaulo mutex_exit(&fasttrap_cpuc_pid_lock[i]); 449179193Sjb } 450299003Smarkj#else 451299003Smarkj rm_wlock(&fasttrap_tp_lock); 452299003Smarkj rm_wunlock(&fasttrap_tp_lock); 453299003Smarkj#endif 454179193Sjb} 455179193Sjb 456179193Sjb/* 457250953Smarkj * This function performs asynchronous cleanup of fasttrap providers. The 458250953Smarkj * Solaris implementation of this mechanism use a timeout that's activated in 459250953Smarkj * fasttrap_pid_cleanup(), but this doesn't work in FreeBSD: one may sleep while 460250953Smarkj * holding the DTrace mutexes, but it is unsafe to sleep in a callout handler. 461250953Smarkj * Thus we use a dedicated process to perform the cleanup when requested. 462179193Sjb */ 463179193Sjb/*ARGSUSED*/ 464179193Sjbstatic void 465179193Sjbfasttrap_pid_cleanup_cb(void *data) 466179193Sjb{ 467179193Sjb fasttrap_provider_t **fpp, *fp; 468179193Sjb fasttrap_bucket_t *bucket; 469179193Sjb dtrace_provider_id_t provid; 470248983Spfg int i, later = 0, rval; 471179193Sjb 472250953Smarkj mtx_lock(&fasttrap_cleanup_mtx); 473250953Smarkj while (!fasttrap_cleanup_drain || later > 0) { 474179193Sjb fasttrap_cleanup_work = 0; 475211738Srpaulo mtx_unlock(&fasttrap_cleanup_mtx); 476179193Sjb 477179193Sjb later = 0; 478179193Sjb 479179193Sjb /* 480179193Sjb * Iterate over all the providers trying to remove the marked 481179193Sjb * ones. If a provider is marked but not retired, we just 482179193Sjb * have to take a crack at removing it -- it's no big deal if 483179193Sjb * we can't. 484179193Sjb */ 485179193Sjb for (i = 0; i < fasttrap_provs.fth_nent; i++) { 486179193Sjb bucket = &fasttrap_provs.fth_table[i]; 487179193Sjb mutex_enter(&bucket->ftb_mtx); 488179193Sjb fpp = (fasttrap_provider_t **)&bucket->ftb_data; 489179193Sjb 490179193Sjb while ((fp = *fpp) != NULL) { 491179193Sjb if (!fp->ftp_marked) { 492179193Sjb fpp = &fp->ftp_next; 493179193Sjb continue; 494179193Sjb } 495179193Sjb 496179193Sjb mutex_enter(&fp->ftp_mtx); 497179193Sjb 498179193Sjb /* 499179193Sjb * If this provider has consumers actively 500179193Sjb * creating probes (ftp_ccount) or is a USDT 501179193Sjb * provider (ftp_mcount), we can't unregister 502179193Sjb * or even condense. 503179193Sjb */ 504179193Sjb if (fp->ftp_ccount != 0 || 505179193Sjb fp->ftp_mcount != 0) { 506179193Sjb mutex_exit(&fp->ftp_mtx); 507179193Sjb fp->ftp_marked = 0; 508179193Sjb continue; 509179193Sjb } 510179193Sjb 511179193Sjb if (!fp->ftp_retired || fp->ftp_rcount != 0) 512179193Sjb fp->ftp_marked = 0; 513179193Sjb 514179193Sjb mutex_exit(&fp->ftp_mtx); 515179193Sjb 516179193Sjb /* 517179193Sjb * If we successfully unregister this 518179193Sjb * provider we can remove it from the hash 519179193Sjb * chain and free the memory. If our attempt 520179193Sjb * to unregister fails and this is a retired 521179193Sjb * provider, increment our flag to try again 522179193Sjb * pretty soon. If we've consumed more than 523179193Sjb * half of our total permitted number of 524179193Sjb * probes call dtrace_condense() to try to 525179193Sjb * clean out the unenabled probes. 526179193Sjb */ 527179193Sjb provid = fp->ftp_provid; 528248983Spfg if ((rval = dtrace_unregister(provid)) != 0) { 529179193Sjb if (fasttrap_total > fasttrap_max / 2) 530179193Sjb (void) dtrace_condense(provid); 531248983Spfg 532248983Spfg if (rval == EAGAIN) 533248983Spfg fp->ftp_marked = 1; 534248983Spfg 535179193Sjb later += fp->ftp_marked; 536179193Sjb fpp = &fp->ftp_next; 537179193Sjb } else { 538179193Sjb *fpp = fp->ftp_next; 539179193Sjb fasttrap_provider_free(fp); 540179193Sjb } 541179193Sjb } 542179193Sjb mutex_exit(&bucket->ftb_mtx); 543179193Sjb } 544250953Smarkj mtx_lock(&fasttrap_cleanup_mtx); 545179193Sjb 546250953Smarkj /* 547250953Smarkj * If we were unable to retire a provider, try again after a 548250953Smarkj * second. This situation can occur in certain circumstances 549250953Smarkj * where providers cannot be unregistered even though they have 550250953Smarkj * no probes enabled because of an execution of dtrace -l or 551250953Smarkj * something similar. 552250953Smarkj */ 553250953Smarkj if (later > 0 || fasttrap_cleanup_work || 554250953Smarkj fasttrap_cleanup_drain) { 555250953Smarkj mtx_unlock(&fasttrap_cleanup_mtx); 556250953Smarkj pause("ftclean", hz); 557250953Smarkj mtx_lock(&fasttrap_cleanup_mtx); 558250953Smarkj } else 559250953Smarkj mtx_sleep(&fasttrap_cleanup_cv, &fasttrap_cleanup_mtx, 560250953Smarkj 0, "ftcl", 0); 561179193Sjb } 562179193Sjb 563179193Sjb /* 564250953Smarkj * Wake up the thread in fasttrap_unload() now that we're done. 565179193Sjb */ 566250953Smarkj wakeup(&fasttrap_cleanup_drain); 567250953Smarkj mtx_unlock(&fasttrap_cleanup_mtx); 568179193Sjb 569250953Smarkj kthread_exit(); 570179193Sjb} 571179193Sjb 572179193Sjb/* 573179193Sjb * Activates the asynchronous cleanup mechanism. 574179193Sjb */ 575179193Sjbstatic void 576179193Sjbfasttrap_pid_cleanup(void) 577179193Sjb{ 578211738Srpaulo 579211738Srpaulo mtx_lock(&fasttrap_cleanup_mtx); 580250953Smarkj if (!fasttrap_cleanup_work) { 581250953Smarkj fasttrap_cleanup_work = 1; 582250953Smarkj wakeup(&fasttrap_cleanup_cv); 583250953Smarkj } 584211738Srpaulo mtx_unlock(&fasttrap_cleanup_mtx); 585179193Sjb} 586179193Sjb 587179193Sjb/* 588179193Sjb * This is called from cfork() via dtrace_fasttrap_fork(). The child 589179198Sjb * process's address space is (roughly) a copy of the parent process's so 590179193Sjb * we have to remove all the instrumentation we had previously enabled in the 591179193Sjb * parent. 592179193Sjb */ 593179193Sjbstatic void 594179193Sjbfasttrap_fork(proc_t *p, proc_t *cp) 595179193Sjb{ 596297077Smav#ifndef illumos 597269342Smarkj fasttrap_scrblock_t *scrblk; 598269342Smarkj fasttrap_proc_t *fprc = NULL; 599269342Smarkj#endif 600179193Sjb pid_t ppid = p->p_pid; 601179193Sjb int i; 602179193Sjb 603297077Smav#ifdef illumos 604179193Sjb ASSERT(curproc == p); 605179193Sjb ASSERT(p->p_proc_flag & P_PR_LOCK); 606211738Srpaulo#else 607211738Srpaulo PROC_LOCK_ASSERT(p, MA_OWNED); 608211738Srpaulo#endif 609297077Smav#ifdef illumos 610179193Sjb ASSERT(p->p_dtrace_count > 0); 611211738Srpaulo#else 612212357Srpaulo if (p->p_dtrace_helpers) { 613212357Srpaulo /* 614212357Srpaulo * dtrace_helpers_duplicate() allocates memory. 615212357Srpaulo */ 616212494Srpaulo _PHOLD(cp); 617212357Srpaulo PROC_UNLOCK(p); 618212357Srpaulo PROC_UNLOCK(cp); 619212357Srpaulo dtrace_helpers_duplicate(p, cp); 620212357Srpaulo PROC_LOCK(cp); 621212357Srpaulo PROC_LOCK(p); 622212494Srpaulo _PRELE(cp); 623212357Srpaulo } 624211738Srpaulo /* 625211738Srpaulo * This check is purposely here instead of in kern_fork.c because, 626211738Srpaulo * for legal resons, we cannot include the dtrace_cddl.h header 627211738Srpaulo * inside kern_fork.c and insert if-clause there. 628211738Srpaulo */ 629211738Srpaulo if (p->p_dtrace_count == 0) 630211738Srpaulo return; 631211738Srpaulo#endif 632179193Sjb ASSERT(cp->p_dtrace_count == 0); 633179193Sjb 634179193Sjb /* 635179193Sjb * This would be simpler and faster if we maintained per-process 636179193Sjb * hash tables of enabled tracepoints. It could, however, potentially 637179193Sjb * slow down execution of a tracepoint since we'd need to go 638179193Sjb * through two levels of indirection. In the future, we should 639179193Sjb * consider either maintaining per-process ancillary lists of 640179193Sjb * enabled tracepoints or hanging a pointer to a per-process hash 641179193Sjb * table of enabled tracepoints off the proc structure. 642179193Sjb */ 643179193Sjb 644179193Sjb /* 645179193Sjb * We don't have to worry about the child process disappearing 646179193Sjb * because we're in fork(). 647179193Sjb */ 648297077Smav#ifdef illumos 649211738Srpaulo mtx_lock_spin(&cp->p_slock); 650179193Sjb sprlock_proc(cp); 651211738Srpaulo mtx_unlock_spin(&cp->p_slock); 652212494Srpaulo#else 653254198Srpaulo /* 654254198Srpaulo * fasttrap_tracepoint_remove() expects the child process to be 655254198Srpaulo * unlocked and the VM then expects curproc to be unlocked. 656254198Srpaulo */ 657212494Srpaulo _PHOLD(cp); 658254198Srpaulo PROC_UNLOCK(cp); 659254198Srpaulo PROC_UNLOCK(p); 660211738Srpaulo#endif 661179193Sjb 662179193Sjb /* 663179193Sjb * Iterate over every tracepoint looking for ones that belong to the 664179193Sjb * parent process, and remove each from the child process. 665179193Sjb */ 666179193Sjb for (i = 0; i < fasttrap_tpoints.fth_nent; i++) { 667179193Sjb fasttrap_tracepoint_t *tp; 668179193Sjb fasttrap_bucket_t *bucket = &fasttrap_tpoints.fth_table[i]; 669179193Sjb 670179193Sjb mutex_enter(&bucket->ftb_mtx); 671179193Sjb for (tp = bucket->ftb_data; tp != NULL; tp = tp->ftt_next) { 672179193Sjb if (tp->ftt_pid == ppid && 673179193Sjb tp->ftt_proc->ftpc_acount != 0) { 674179193Sjb int ret = fasttrap_tracepoint_remove(cp, tp); 675179193Sjb ASSERT(ret == 0); 676179198Sjb 677179198Sjb /* 678179198Sjb * The count of active providers can only be 679179198Sjb * decremented (i.e. to zero) during exec, 680179198Sjb * exit, and removal of a meta provider so it 681179198Sjb * should be impossible to drop the count 682179198Sjb * mid-fork. 683179198Sjb */ 684179198Sjb ASSERT(tp->ftt_proc->ftpc_acount != 0); 685297077Smav#ifndef illumos 686269342Smarkj fprc = tp->ftt_proc; 687269342Smarkj#endif 688179193Sjb } 689179193Sjb } 690179193Sjb mutex_exit(&bucket->ftb_mtx); 691269342Smarkj 692297077Smav#ifndef illumos 693269342Smarkj /* 694269342Smarkj * Unmap any scratch space inherited from the parent's address 695269342Smarkj * space. 696269342Smarkj */ 697269342Smarkj if (fprc != NULL) { 698269342Smarkj mutex_enter(&fprc->ftpc_mtx); 699269342Smarkj LIST_FOREACH(scrblk, &fprc->ftpc_scrblks, ftsb_next) { 700269342Smarkj vm_map_remove(&cp->p_vmspace->vm_map, 701269342Smarkj scrblk->ftsb_addr, 702269342Smarkj scrblk->ftsb_addr + FASTTRAP_SCRBLOCK_SIZE); 703269342Smarkj } 704269342Smarkj mutex_exit(&fprc->ftpc_mtx); 705269342Smarkj } 706269342Smarkj#endif 707179193Sjb } 708179193Sjb 709297077Smav#ifdef illumos 710179193Sjb mutex_enter(&cp->p_lock); 711179193Sjb sprunlock(cp); 712212494Srpaulo#else 713254198Srpaulo PROC_LOCK(p); 714254198Srpaulo PROC_LOCK(cp); 715212494Srpaulo _PRELE(cp); 716211738Srpaulo#endif 717179193Sjb} 718179193Sjb 719179193Sjb/* 720179193Sjb * This is called from proc_exit() or from exec_common() if p_dtrace_probes 721179193Sjb * is set on the proc structure to indicate that there is a pid provider 722179193Sjb * associated with this process. 723179193Sjb */ 724179193Sjbstatic void 725179193Sjbfasttrap_exec_exit(proc_t *p) 726179193Sjb{ 727297077Smav#ifndef illumos 728269342Smarkj struct thread *td; 729269342Smarkj#endif 730269342Smarkj 731297077Smav#ifdef illumos 732179193Sjb ASSERT(p == curproc); 733269342Smarkj#else 734211738Srpaulo PROC_LOCK_ASSERT(p, MA_OWNED); 735212494Srpaulo _PHOLD(p); 736269342Smarkj /* 737269342Smarkj * Since struct threads may be recycled, we cannot rely on t_dtrace_sscr 738269342Smarkj * fields to be zeroed by kdtrace_thread_ctor. Thus we must zero it 739269342Smarkj * ourselves when a process exits. 740269342Smarkj */ 741269342Smarkj FOREACH_THREAD_IN_PROC(p, td) 742269342Smarkj td->t_dtrace_sscr = NULL; 743211738Srpaulo PROC_UNLOCK(p); 744269342Smarkj#endif 745179193Sjb 746179193Sjb /* 747179193Sjb * We clean up the pid provider for this process here; user-land 748179193Sjb * static probes are handled by the meta-provider remove entry point. 749179193Sjb */ 750179193Sjb fasttrap_provider_retire(p->p_pid, FASTTRAP_PID_NAME, 0); 751297077Smav#ifndef illumos 752212357Srpaulo if (p->p_dtrace_helpers) 753212357Srpaulo dtrace_helpers_destroy(p); 754211738Srpaulo PROC_LOCK(p); 755212494Srpaulo _PRELE(p); 756269342Smarkj#endif 757179193Sjb} 758179193Sjb 759179193Sjb 760179193Sjb/*ARGSUSED*/ 761179193Sjbstatic void 762211738Srpaulofasttrap_pid_provide(void *arg, dtrace_probedesc_t *desc) 763179193Sjb{ 764179193Sjb /* 765179193Sjb * There are no "default" pid probes. 766179193Sjb */ 767179193Sjb} 768179193Sjb 769179193Sjbstatic int 770179193Sjbfasttrap_tracepoint_enable(proc_t *p, fasttrap_probe_t *probe, uint_t index) 771179193Sjb{ 772179193Sjb fasttrap_tracepoint_t *tp, *new_tp = NULL; 773179193Sjb fasttrap_bucket_t *bucket; 774179193Sjb fasttrap_id_t *id; 775179193Sjb pid_t pid; 776179193Sjb uintptr_t pc; 777179193Sjb 778179193Sjb ASSERT(index < probe->ftp_ntps); 779179193Sjb 780179193Sjb pid = probe->ftp_pid; 781179193Sjb pc = probe->ftp_tps[index].fit_tp->ftt_pc; 782179193Sjb id = &probe->ftp_tps[index].fit_id; 783179193Sjb 784179193Sjb ASSERT(probe->ftp_tps[index].fit_tp->ftt_pid == pid); 785179193Sjb 786297077Smav#ifdef illumos 787179193Sjb ASSERT(!(p->p_flag & SVFORK)); 788211738Srpaulo#endif 789179193Sjb 790179193Sjb /* 791179193Sjb * Before we make any modifications, make sure we've imposed a barrier 792179193Sjb * on the generation in which this probe was last modified. 793179193Sjb */ 794179193Sjb fasttrap_mod_barrier(probe->ftp_gen); 795179193Sjb 796179193Sjb bucket = &fasttrap_tpoints.fth_table[FASTTRAP_TPOINTS_INDEX(pid, pc)]; 797179193Sjb 798179193Sjb /* 799179193Sjb * If the tracepoint has already been enabled, just add our id to the 800179193Sjb * list of interested probes. This may be our second time through 801179193Sjb * this path in which case we'll have constructed the tracepoint we'd 802179193Sjb * like to install. If we can't find a match, and have an allocated 803179193Sjb * tracepoint ready to go, enable that one now. 804179193Sjb * 805179193Sjb * A tracepoint whose process is defunct is also considered defunct. 806179193Sjb */ 807179193Sjbagain: 808179193Sjb mutex_enter(&bucket->ftb_mtx); 809179193Sjb for (tp = bucket->ftb_data; tp != NULL; tp = tp->ftt_next) { 810179198Sjb /* 811179198Sjb * Note that it's safe to access the active count on the 812179198Sjb * associated proc structure because we know that at least one 813179198Sjb * provider (this one) will still be around throughout this 814179198Sjb * operation. 815179198Sjb */ 816179193Sjb if (tp->ftt_pid != pid || tp->ftt_pc != pc || 817179193Sjb tp->ftt_proc->ftpc_acount == 0) 818179193Sjb continue; 819179193Sjb 820179193Sjb /* 821179193Sjb * Now that we've found a matching tracepoint, it would be 822179193Sjb * a decent idea to confirm that the tracepoint is still 823179193Sjb * enabled and the trap instruction hasn't been overwritten. 824179193Sjb * Since this is a little hairy, we'll punt for now. 825179193Sjb */ 826179193Sjb 827179193Sjb /* 828179193Sjb * This can't be the first interested probe. We don't have 829179193Sjb * to worry about another thread being in the midst of 830179193Sjb * deleting this tracepoint (which would be the only valid 831179193Sjb * reason for a tracepoint to have no interested probes) 832179193Sjb * since we're holding P_PR_LOCK for this process. 833179193Sjb */ 834179193Sjb ASSERT(tp->ftt_ids != NULL || tp->ftt_retids != NULL); 835179193Sjb 836179193Sjb switch (id->fti_ptype) { 837179193Sjb case DTFTP_ENTRY: 838179193Sjb case DTFTP_OFFSETS: 839179193Sjb case DTFTP_IS_ENABLED: 840179193Sjb id->fti_next = tp->ftt_ids; 841179193Sjb membar_producer(); 842179193Sjb tp->ftt_ids = id; 843179193Sjb membar_producer(); 844179193Sjb break; 845179193Sjb 846179193Sjb case DTFTP_RETURN: 847179193Sjb case DTFTP_POST_OFFSETS: 848179193Sjb id->fti_next = tp->ftt_retids; 849179193Sjb membar_producer(); 850179193Sjb tp->ftt_retids = id; 851179193Sjb membar_producer(); 852179193Sjb break; 853179193Sjb 854179193Sjb default: 855179193Sjb ASSERT(0); 856179193Sjb } 857179193Sjb 858179193Sjb mutex_exit(&bucket->ftb_mtx); 859179193Sjb 860179193Sjb if (new_tp != NULL) { 861179193Sjb new_tp->ftt_ids = NULL; 862179193Sjb new_tp->ftt_retids = NULL; 863179193Sjb } 864179193Sjb 865179193Sjb return (0); 866179193Sjb } 867179193Sjb 868179193Sjb /* 869179193Sjb * If we have a good tracepoint ready to go, install it now while 870179193Sjb * we have the lock held and no one can screw with us. 871179193Sjb */ 872179193Sjb if (new_tp != NULL) { 873179193Sjb int rc = 0; 874179193Sjb 875179193Sjb new_tp->ftt_next = bucket->ftb_data; 876179193Sjb membar_producer(); 877179193Sjb bucket->ftb_data = new_tp; 878179193Sjb membar_producer(); 879179193Sjb mutex_exit(&bucket->ftb_mtx); 880179193Sjb 881179193Sjb /* 882179193Sjb * Activate the tracepoint in the ISA-specific manner. 883179193Sjb * If this fails, we need to report the failure, but 884179193Sjb * indicate that this tracepoint must still be disabled 885179193Sjb * by calling fasttrap_tracepoint_disable(). 886179193Sjb */ 887179193Sjb if (fasttrap_tracepoint_install(p, new_tp) != 0) 888179193Sjb rc = FASTTRAP_ENABLE_PARTIAL; 889179193Sjb 890179193Sjb /* 891179193Sjb * Increment the count of the number of tracepoints active in 892179193Sjb * the victim process. 893179193Sjb */ 894297077Smav#ifdef illumos 895179193Sjb ASSERT(p->p_proc_flag & P_PR_LOCK); 896211738Srpaulo#endif 897179193Sjb p->p_dtrace_count++; 898179193Sjb 899179193Sjb return (rc); 900179193Sjb } 901179193Sjb 902179193Sjb mutex_exit(&bucket->ftb_mtx); 903179193Sjb 904179193Sjb /* 905179193Sjb * Initialize the tracepoint that's been preallocated with the probe. 906179193Sjb */ 907179193Sjb new_tp = probe->ftp_tps[index].fit_tp; 908179193Sjb 909179193Sjb ASSERT(new_tp->ftt_pid == pid); 910179193Sjb ASSERT(new_tp->ftt_pc == pc); 911179193Sjb ASSERT(new_tp->ftt_proc == probe->ftp_prov->ftp_proc); 912179193Sjb ASSERT(new_tp->ftt_ids == NULL); 913179193Sjb ASSERT(new_tp->ftt_retids == NULL); 914179193Sjb 915179193Sjb switch (id->fti_ptype) { 916179193Sjb case DTFTP_ENTRY: 917179193Sjb case DTFTP_OFFSETS: 918179193Sjb case DTFTP_IS_ENABLED: 919179193Sjb id->fti_next = NULL; 920179193Sjb new_tp->ftt_ids = id; 921179193Sjb break; 922179193Sjb 923179193Sjb case DTFTP_RETURN: 924179193Sjb case DTFTP_POST_OFFSETS: 925179193Sjb id->fti_next = NULL; 926179193Sjb new_tp->ftt_retids = id; 927179193Sjb break; 928179193Sjb 929179193Sjb default: 930179193Sjb ASSERT(0); 931179193Sjb } 932179193Sjb 933179193Sjb /* 934179193Sjb * If the ISA-dependent initialization goes to plan, go back to the 935179193Sjb * beginning and try to install this freshly made tracepoint. 936179193Sjb */ 937179193Sjb if (fasttrap_tracepoint_init(p, new_tp, pc, id->fti_ptype) == 0) 938179193Sjb goto again; 939179193Sjb 940179193Sjb new_tp->ftt_ids = NULL; 941179193Sjb new_tp->ftt_retids = NULL; 942179193Sjb 943179193Sjb return (FASTTRAP_ENABLE_FAIL); 944179193Sjb} 945179193Sjb 946179193Sjbstatic void 947179193Sjbfasttrap_tracepoint_disable(proc_t *p, fasttrap_probe_t *probe, uint_t index) 948179193Sjb{ 949179193Sjb fasttrap_bucket_t *bucket; 950179193Sjb fasttrap_provider_t *provider = probe->ftp_prov; 951179193Sjb fasttrap_tracepoint_t **pp, *tp; 952211738Srpaulo fasttrap_id_t *id, **idp = NULL; 953179193Sjb pid_t pid; 954179193Sjb uintptr_t pc; 955179193Sjb 956179193Sjb ASSERT(index < probe->ftp_ntps); 957179193Sjb 958179193Sjb pid = probe->ftp_pid; 959179193Sjb pc = probe->ftp_tps[index].fit_tp->ftt_pc; 960179193Sjb id = &probe->ftp_tps[index].fit_id; 961179193Sjb 962179193Sjb ASSERT(probe->ftp_tps[index].fit_tp->ftt_pid == pid); 963179193Sjb 964179193Sjb /* 965179193Sjb * Find the tracepoint and make sure that our id is one of the 966179193Sjb * ones registered with it. 967179193Sjb */ 968179193Sjb bucket = &fasttrap_tpoints.fth_table[FASTTRAP_TPOINTS_INDEX(pid, pc)]; 969179193Sjb mutex_enter(&bucket->ftb_mtx); 970179193Sjb for (tp = bucket->ftb_data; tp != NULL; tp = tp->ftt_next) { 971179193Sjb if (tp->ftt_pid == pid && tp->ftt_pc == pc && 972179193Sjb tp->ftt_proc == provider->ftp_proc) 973179193Sjb break; 974179193Sjb } 975179193Sjb 976179193Sjb /* 977179193Sjb * If we somehow lost this tracepoint, we're in a world of hurt. 978179193Sjb */ 979179193Sjb ASSERT(tp != NULL); 980179193Sjb 981179193Sjb switch (id->fti_ptype) { 982179193Sjb case DTFTP_ENTRY: 983179193Sjb case DTFTP_OFFSETS: 984179193Sjb case DTFTP_IS_ENABLED: 985179193Sjb ASSERT(tp->ftt_ids != NULL); 986179193Sjb idp = &tp->ftt_ids; 987179193Sjb break; 988179193Sjb 989179193Sjb case DTFTP_RETURN: 990179193Sjb case DTFTP_POST_OFFSETS: 991179193Sjb ASSERT(tp->ftt_retids != NULL); 992179193Sjb idp = &tp->ftt_retids; 993179193Sjb break; 994179193Sjb 995179193Sjb default: 996179193Sjb ASSERT(0); 997179193Sjb } 998179193Sjb 999179193Sjb while ((*idp)->fti_probe != probe) { 1000179193Sjb idp = &(*idp)->fti_next; 1001179193Sjb ASSERT(*idp != NULL); 1002179193Sjb } 1003179193Sjb 1004179193Sjb id = *idp; 1005179193Sjb *idp = id->fti_next; 1006179193Sjb membar_producer(); 1007179193Sjb 1008179193Sjb ASSERT(id->fti_probe == probe); 1009179193Sjb 1010179193Sjb /* 1011179193Sjb * If there are other registered enablings of this tracepoint, we're 1012179193Sjb * all done, but if this was the last probe assocated with this 1013179193Sjb * this tracepoint, we need to remove and free it. 1014179193Sjb */ 1015179193Sjb if (tp->ftt_ids != NULL || tp->ftt_retids != NULL) { 1016179193Sjb 1017179193Sjb /* 1018179193Sjb * If the current probe's tracepoint is in use, swap it 1019179193Sjb * for an unused tracepoint. 1020179193Sjb */ 1021179193Sjb if (tp == probe->ftp_tps[index].fit_tp) { 1022179193Sjb fasttrap_probe_t *tmp_probe; 1023179193Sjb fasttrap_tracepoint_t **tmp_tp; 1024179193Sjb uint_t tmp_index; 1025179193Sjb 1026179193Sjb if (tp->ftt_ids != NULL) { 1027179193Sjb tmp_probe = tp->ftt_ids->fti_probe; 1028179193Sjb /* LINTED - alignment */ 1029179193Sjb tmp_index = FASTTRAP_ID_INDEX(tp->ftt_ids); 1030179193Sjb tmp_tp = &tmp_probe->ftp_tps[tmp_index].fit_tp; 1031179193Sjb } else { 1032179193Sjb tmp_probe = tp->ftt_retids->fti_probe; 1033179193Sjb /* LINTED - alignment */ 1034179193Sjb tmp_index = FASTTRAP_ID_INDEX(tp->ftt_retids); 1035179193Sjb tmp_tp = &tmp_probe->ftp_tps[tmp_index].fit_tp; 1036179193Sjb } 1037179193Sjb 1038179193Sjb ASSERT(*tmp_tp != NULL); 1039179193Sjb ASSERT(*tmp_tp != probe->ftp_tps[index].fit_tp); 1040179193Sjb ASSERT((*tmp_tp)->ftt_ids == NULL); 1041179193Sjb ASSERT((*tmp_tp)->ftt_retids == NULL); 1042179193Sjb 1043179193Sjb probe->ftp_tps[index].fit_tp = *tmp_tp; 1044179193Sjb *tmp_tp = tp; 1045179193Sjb } 1046179193Sjb 1047179193Sjb mutex_exit(&bucket->ftb_mtx); 1048179193Sjb 1049179193Sjb /* 1050179193Sjb * Tag the modified probe with the generation in which it was 1051179193Sjb * changed. 1052179193Sjb */ 1053179193Sjb probe->ftp_gen = fasttrap_mod_gen; 1054179193Sjb return; 1055179193Sjb } 1056179193Sjb 1057179193Sjb mutex_exit(&bucket->ftb_mtx); 1058179193Sjb 1059179193Sjb /* 1060179193Sjb * We can't safely remove the tracepoint from the set of active 1061179193Sjb * tracepoints until we've actually removed the fasttrap instruction 1062179193Sjb * from the process's text. We can, however, operate on this 1063179193Sjb * tracepoint secure in the knowledge that no other thread is going to 1064179193Sjb * be looking at it since we hold P_PR_LOCK on the process if it's 1065179193Sjb * live or we hold the provider lock on the process if it's dead and 1066179193Sjb * gone. 1067179193Sjb */ 1068179193Sjb 1069179193Sjb /* 1070179193Sjb * We only need to remove the actual instruction if we're looking 1071179193Sjb * at an existing process 1072179193Sjb */ 1073179193Sjb if (p != NULL) { 1074179193Sjb /* 1075179193Sjb * If we fail to restore the instruction we need to kill 1076179193Sjb * this process since it's in a completely unrecoverable 1077179193Sjb * state. 1078179193Sjb */ 1079179193Sjb if (fasttrap_tracepoint_remove(p, tp) != 0) 1080179193Sjb fasttrap_sigtrap(p, NULL, pc); 1081179193Sjb 1082179193Sjb /* 1083179193Sjb * Decrement the count of the number of tracepoints active 1084179193Sjb * in the victim process. 1085179193Sjb */ 1086297077Smav#ifdef illumos 1087179193Sjb ASSERT(p->p_proc_flag & P_PR_LOCK); 1088211738Srpaulo#endif 1089179193Sjb p->p_dtrace_count--; 1090179193Sjb } 1091179193Sjb 1092179193Sjb /* 1093179193Sjb * Remove the probe from the hash table of active tracepoints. 1094179193Sjb */ 1095179193Sjb mutex_enter(&bucket->ftb_mtx); 1096179193Sjb pp = (fasttrap_tracepoint_t **)&bucket->ftb_data; 1097179193Sjb ASSERT(*pp != NULL); 1098179193Sjb while (*pp != tp) { 1099179193Sjb pp = &(*pp)->ftt_next; 1100179193Sjb ASSERT(*pp != NULL); 1101179193Sjb } 1102179193Sjb 1103179193Sjb *pp = tp->ftt_next; 1104179193Sjb membar_producer(); 1105179193Sjb 1106179193Sjb mutex_exit(&bucket->ftb_mtx); 1107179193Sjb 1108179193Sjb /* 1109179193Sjb * Tag the modified probe with the generation in which it was changed. 1110179193Sjb */ 1111179193Sjb probe->ftp_gen = fasttrap_mod_gen; 1112179193Sjb} 1113179193Sjb 1114179193Sjbstatic void 1115179193Sjbfasttrap_enable_callbacks(void) 1116179193Sjb{ 1117179193Sjb /* 1118179193Sjb * We don't have to play the rw lock game here because we're 1119179193Sjb * providing something rather than taking something away -- 1120179193Sjb * we can be sure that no threads have tried to follow this 1121179193Sjb * function pointer yet. 1122179193Sjb */ 1123179193Sjb mutex_enter(&fasttrap_count_mtx); 1124179193Sjb if (fasttrap_pid_count == 0) { 1125179193Sjb ASSERT(dtrace_pid_probe_ptr == NULL); 1126179193Sjb ASSERT(dtrace_return_probe_ptr == NULL); 1127179193Sjb dtrace_pid_probe_ptr = &fasttrap_pid_probe; 1128179193Sjb dtrace_return_probe_ptr = &fasttrap_return_probe; 1129179193Sjb } 1130179193Sjb ASSERT(dtrace_pid_probe_ptr == &fasttrap_pid_probe); 1131179193Sjb ASSERT(dtrace_return_probe_ptr == &fasttrap_return_probe); 1132179193Sjb fasttrap_pid_count++; 1133179193Sjb mutex_exit(&fasttrap_count_mtx); 1134179193Sjb} 1135179193Sjb 1136179193Sjbstatic void 1137179193Sjbfasttrap_disable_callbacks(void) 1138179193Sjb{ 1139297077Smav#ifdef illumos 1140179193Sjb ASSERT(MUTEX_HELD(&cpu_lock)); 1141211738Srpaulo#endif 1142179193Sjb 1143211738Srpaulo 1144179193Sjb mutex_enter(&fasttrap_count_mtx); 1145179193Sjb ASSERT(fasttrap_pid_count > 0); 1146179193Sjb fasttrap_pid_count--; 1147179193Sjb if (fasttrap_pid_count == 0) { 1148297077Smav#ifdef illumos 1149179193Sjb cpu_t *cur, *cpu = CPU; 1150179193Sjb 1151179193Sjb for (cur = cpu->cpu_next_onln; cur != cpu; 1152179193Sjb cur = cur->cpu_next_onln) { 1153179193Sjb rw_enter(&cur->cpu_ft_lock, RW_WRITER); 1154179193Sjb } 1155211738Srpaulo#endif 1156179193Sjb dtrace_pid_probe_ptr = NULL; 1157179193Sjb dtrace_return_probe_ptr = NULL; 1158297077Smav#ifdef illumos 1159179193Sjb for (cur = cpu->cpu_next_onln; cur != cpu; 1160179193Sjb cur = cur->cpu_next_onln) { 1161179193Sjb rw_exit(&cur->cpu_ft_lock); 1162179193Sjb } 1163211738Srpaulo#endif 1164179193Sjb } 1165179193Sjb mutex_exit(&fasttrap_count_mtx); 1166179193Sjb} 1167179193Sjb 1168179193Sjb/*ARGSUSED*/ 1169179193Sjbstatic void 1170179193Sjbfasttrap_pid_enable(void *arg, dtrace_id_t id, void *parg) 1171179193Sjb{ 1172179193Sjb fasttrap_probe_t *probe = parg; 1173211738Srpaulo proc_t *p = NULL; 1174179193Sjb int i, rc; 1175179193Sjb 1176179193Sjb ASSERT(probe != NULL); 1177179193Sjb ASSERT(!probe->ftp_enabled); 1178179193Sjb ASSERT(id == probe->ftp_id); 1179297077Smav#ifdef illumos 1180179193Sjb ASSERT(MUTEX_HELD(&cpu_lock)); 1181211738Srpaulo#endif 1182179193Sjb 1183179193Sjb /* 1184179193Sjb * Increment the count of enabled probes on this probe's provider; 1185179193Sjb * the provider can't go away while the probe still exists. We 1186179193Sjb * must increment this even if we aren't able to properly enable 1187179193Sjb * this probe. 1188179193Sjb */ 1189179193Sjb mutex_enter(&probe->ftp_prov->ftp_mtx); 1190179193Sjb probe->ftp_prov->ftp_rcount++; 1191179193Sjb mutex_exit(&probe->ftp_prov->ftp_mtx); 1192179193Sjb 1193179193Sjb /* 1194179193Sjb * If this probe's provider is retired (meaning it was valid in a 1195179193Sjb * previously exec'ed incarnation of this address space), bail out. The 1196179193Sjb * provider can't go away while we're in this code path. 1197179193Sjb */ 1198179193Sjb if (probe->ftp_prov->ftp_retired) 1199179193Sjb return; 1200179193Sjb 1201179193Sjb /* 1202179193Sjb * If we can't find the process, it may be that we're in the context of 1203179193Sjb * a fork in which the traced process is being born and we're copying 1204179193Sjb * USDT probes. Otherwise, the process is gone so bail. 1205179193Sjb */ 1206297077Smav#ifdef illumos 1207179193Sjb if ((p = sprlock(probe->ftp_pid)) == NULL) { 1208179193Sjb if ((curproc->p_flag & SFORKING) == 0) 1209179193Sjb return; 1210179193Sjb 1211179193Sjb mutex_enter(&pidlock); 1212179193Sjb p = prfind(probe->ftp_pid); 1213179193Sjb 1214179193Sjb /* 1215179193Sjb * Confirm that curproc is indeed forking the process in which 1216179193Sjb * we're trying to enable probes. 1217179193Sjb */ 1218179193Sjb ASSERT(p != NULL); 1219179193Sjb ASSERT(p->p_parent == curproc); 1220179193Sjb ASSERT(p->p_stat == SIDL); 1221179193Sjb 1222179193Sjb mutex_enter(&p->p_lock); 1223179193Sjb mutex_exit(&pidlock); 1224179193Sjb 1225179193Sjb sprlock_proc(p); 1226179193Sjb } 1227179193Sjb 1228179193Sjb ASSERT(!(p->p_flag & SVFORK)); 1229179193Sjb mutex_exit(&p->p_lock); 1230211738Srpaulo#else 1231211738Srpaulo if ((p = pfind(probe->ftp_pid)) == NULL) 1232211738Srpaulo return; 1233211738Srpaulo#endif 1234179193Sjb 1235179193Sjb /* 1236179193Sjb * We have to enable the trap entry point before any user threads have 1237179193Sjb * the chance to execute the trap instruction we're about to place 1238179193Sjb * in their process's text. 1239179193Sjb */ 1240212494Srpaulo#ifdef __FreeBSD__ 1241212494Srpaulo /* 1242212494Srpaulo * pfind() returns a locked process. 1243212494Srpaulo */ 1244212494Srpaulo _PHOLD(p); 1245211738Srpaulo PROC_UNLOCK(p); 1246212494Srpaulo#endif 1247179193Sjb fasttrap_enable_callbacks(); 1248179193Sjb 1249179193Sjb /* 1250179193Sjb * Enable all the tracepoints and add this probe's id to each 1251179193Sjb * tracepoint's list of active probes. 1252179193Sjb */ 1253179193Sjb for (i = 0; i < probe->ftp_ntps; i++) { 1254179193Sjb if ((rc = fasttrap_tracepoint_enable(p, probe, i)) != 0) { 1255179193Sjb /* 1256179193Sjb * If enabling the tracepoint failed completely, 1257179193Sjb * we don't have to disable it; if the failure 1258179193Sjb * was only partial we must disable it. 1259179193Sjb */ 1260179193Sjb if (rc == FASTTRAP_ENABLE_FAIL) 1261179193Sjb i--; 1262179193Sjb else 1263179193Sjb ASSERT(rc == FASTTRAP_ENABLE_PARTIAL); 1264179193Sjb 1265179193Sjb /* 1266179193Sjb * Back up and pull out all the tracepoints we've 1267179193Sjb * created so far for this probe. 1268179193Sjb */ 1269179193Sjb while (i >= 0) { 1270179193Sjb fasttrap_tracepoint_disable(p, probe, i); 1271179193Sjb i--; 1272179193Sjb } 1273179193Sjb 1274297077Smav#ifdef illumos 1275179193Sjb mutex_enter(&p->p_lock); 1276179193Sjb sprunlock(p); 1277211738Srpaulo#else 1278212494Srpaulo PRELE(p); 1279211738Srpaulo#endif 1280179193Sjb 1281179193Sjb /* 1282179193Sjb * Since we're not actually enabling this probe, 1283179193Sjb * drop our reference on the trap table entry. 1284179193Sjb */ 1285179193Sjb fasttrap_disable_callbacks(); 1286179193Sjb return; 1287179193Sjb } 1288179193Sjb } 1289297077Smav#ifdef illumos 1290179193Sjb mutex_enter(&p->p_lock); 1291179193Sjb sprunlock(p); 1292211738Srpaulo#else 1293212494Srpaulo PRELE(p); 1294211738Srpaulo#endif 1295179193Sjb 1296179193Sjb probe->ftp_enabled = 1; 1297179193Sjb} 1298179193Sjb 1299179193Sjb/*ARGSUSED*/ 1300179193Sjbstatic void 1301179193Sjbfasttrap_pid_disable(void *arg, dtrace_id_t id, void *parg) 1302179193Sjb{ 1303179193Sjb fasttrap_probe_t *probe = parg; 1304179193Sjb fasttrap_provider_t *provider = probe->ftp_prov; 1305179193Sjb proc_t *p; 1306179193Sjb int i, whack = 0; 1307179193Sjb 1308179193Sjb ASSERT(id == probe->ftp_id); 1309179193Sjb 1310211738Srpaulo mutex_enter(&provider->ftp_mtx); 1311211738Srpaulo 1312179193Sjb /* 1313179193Sjb * We won't be able to acquire a /proc-esque lock on the process 1314179193Sjb * iff the process is dead and gone. In this case, we rely on the 1315179193Sjb * provider lock as a point of mutual exclusion to prevent other 1316179193Sjb * DTrace consumers from disabling this probe. 1317179193Sjb */ 1318247049Sgibbs if ((p = pfind(probe->ftp_pid)) != NULL) { 1319212494Srpaulo#ifdef __FreeBSD__ 1320283677Smarkj if (p->p_flag & P_WEXIT) { 1321283677Smarkj PROC_UNLOCK(p); 1322283677Smarkj p = NULL; 1323283677Smarkj } else { 1324283677Smarkj _PHOLD(p); 1325283677Smarkj PROC_UNLOCK(p); 1326283677Smarkj } 1327212494Srpaulo#endif 1328247049Sgibbs } 1329179193Sjb 1330179193Sjb /* 1331179193Sjb * Disable all the associated tracepoints (for fully enabled probes). 1332179193Sjb */ 1333179193Sjb if (probe->ftp_enabled) { 1334179193Sjb for (i = 0; i < probe->ftp_ntps; i++) { 1335179193Sjb fasttrap_tracepoint_disable(p, probe, i); 1336179193Sjb } 1337179193Sjb } 1338179193Sjb 1339179193Sjb ASSERT(provider->ftp_rcount > 0); 1340179193Sjb provider->ftp_rcount--; 1341179193Sjb 1342179193Sjb if (p != NULL) { 1343179193Sjb /* 1344179193Sjb * Even though we may not be able to remove it entirely, we 1345179193Sjb * mark this retired provider to get a chance to remove some 1346179193Sjb * of the associated probes. 1347179193Sjb */ 1348179193Sjb if (provider->ftp_retired && !provider->ftp_marked) 1349179193Sjb whack = provider->ftp_marked = 1; 1350179193Sjb mutex_exit(&provider->ftp_mtx); 1351179193Sjb } else { 1352179193Sjb /* 1353179193Sjb * If the process is dead, we're just waiting for the 1354179193Sjb * last probe to be disabled to be able to free it. 1355179193Sjb */ 1356179193Sjb if (provider->ftp_rcount == 0 && !provider->ftp_marked) 1357179193Sjb whack = provider->ftp_marked = 1; 1358179193Sjb mutex_exit(&provider->ftp_mtx); 1359179193Sjb } 1360179193Sjb 1361179193Sjb if (whack) 1362179193Sjb fasttrap_pid_cleanup(); 1363179193Sjb 1364212494Srpaulo#ifdef __FreeBSD__ 1365247049Sgibbs if (p != NULL) 1366247049Sgibbs PRELE(p); 1367212494Srpaulo#endif 1368179193Sjb if (!probe->ftp_enabled) 1369179193Sjb return; 1370179193Sjb 1371179193Sjb probe->ftp_enabled = 0; 1372179193Sjb 1373297077Smav#ifdef illumos 1374179193Sjb ASSERT(MUTEX_HELD(&cpu_lock)); 1375211738Srpaulo#endif 1376179193Sjb fasttrap_disable_callbacks(); 1377179193Sjb} 1378179193Sjb 1379179193Sjb/*ARGSUSED*/ 1380179193Sjbstatic void 1381179193Sjbfasttrap_pid_getargdesc(void *arg, dtrace_id_t id, void *parg, 1382179193Sjb dtrace_argdesc_t *desc) 1383179193Sjb{ 1384179193Sjb fasttrap_probe_t *probe = parg; 1385179193Sjb char *str; 1386179193Sjb int i, ndx; 1387179193Sjb 1388179193Sjb desc->dtargd_native[0] = '\0'; 1389179193Sjb desc->dtargd_xlate[0] = '\0'; 1390179193Sjb 1391179193Sjb if (probe->ftp_prov->ftp_retired != 0 || 1392179193Sjb desc->dtargd_ndx >= probe->ftp_nargs) { 1393179193Sjb desc->dtargd_ndx = DTRACE_ARGNONE; 1394179193Sjb return; 1395179193Sjb } 1396179193Sjb 1397179193Sjb ndx = (probe->ftp_argmap != NULL) ? 1398179193Sjb probe->ftp_argmap[desc->dtargd_ndx] : desc->dtargd_ndx; 1399179193Sjb 1400179193Sjb str = probe->ftp_ntypes; 1401179193Sjb for (i = 0; i < ndx; i++) { 1402179193Sjb str += strlen(str) + 1; 1403179193Sjb } 1404179193Sjb 1405179193Sjb ASSERT(strlen(str + 1) < sizeof (desc->dtargd_native)); 1406179193Sjb (void) strcpy(desc->dtargd_native, str); 1407179193Sjb 1408179193Sjb if (probe->ftp_xtypes == NULL) 1409179193Sjb return; 1410179193Sjb 1411179193Sjb str = probe->ftp_xtypes; 1412179193Sjb for (i = 0; i < desc->dtargd_ndx; i++) { 1413179193Sjb str += strlen(str) + 1; 1414179193Sjb } 1415179193Sjb 1416179193Sjb ASSERT(strlen(str + 1) < sizeof (desc->dtargd_xlate)); 1417179193Sjb (void) strcpy(desc->dtargd_xlate, str); 1418179193Sjb} 1419179193Sjb 1420179193Sjb/*ARGSUSED*/ 1421179193Sjbstatic void 1422179193Sjbfasttrap_pid_destroy(void *arg, dtrace_id_t id, void *parg) 1423179193Sjb{ 1424179193Sjb fasttrap_probe_t *probe = parg; 1425179193Sjb int i; 1426179193Sjb size_t size; 1427179193Sjb 1428179193Sjb ASSERT(probe != NULL); 1429179193Sjb ASSERT(!probe->ftp_enabled); 1430179193Sjb ASSERT(fasttrap_total >= probe->ftp_ntps); 1431179193Sjb 1432179193Sjb atomic_add_32(&fasttrap_total, -probe->ftp_ntps); 1433179193Sjb size = offsetof(fasttrap_probe_t, ftp_tps[probe->ftp_ntps]); 1434179193Sjb 1435179193Sjb if (probe->ftp_gen + 1 >= fasttrap_mod_gen) 1436179193Sjb fasttrap_mod_barrier(probe->ftp_gen); 1437179193Sjb 1438179193Sjb for (i = 0; i < probe->ftp_ntps; i++) { 1439179193Sjb kmem_free(probe->ftp_tps[i].fit_tp, 1440179193Sjb sizeof (fasttrap_tracepoint_t)); 1441179193Sjb } 1442179193Sjb 1443179193Sjb kmem_free(probe, size); 1444179193Sjb} 1445179193Sjb 1446179193Sjb 1447179193Sjbstatic const dtrace_pattr_t pid_attr = { 1448179193Sjb{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_ISA }, 1449179193Sjb{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN }, 1450179193Sjb{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN }, 1451179193Sjb{ DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_ISA }, 1452179193Sjb{ DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN }, 1453179193Sjb}; 1454179193Sjb 1455179193Sjbstatic dtrace_pops_t pid_pops = { 1456179193Sjb fasttrap_pid_provide, 1457179193Sjb NULL, 1458179193Sjb fasttrap_pid_enable, 1459179193Sjb fasttrap_pid_disable, 1460179193Sjb NULL, 1461179193Sjb NULL, 1462179193Sjb fasttrap_pid_getargdesc, 1463179193Sjb fasttrap_pid_getarg, 1464179193Sjb NULL, 1465179193Sjb fasttrap_pid_destroy 1466179193Sjb}; 1467179193Sjb 1468179193Sjbstatic dtrace_pops_t usdt_pops = { 1469179193Sjb fasttrap_pid_provide, 1470179193Sjb NULL, 1471179193Sjb fasttrap_pid_enable, 1472179193Sjb fasttrap_pid_disable, 1473179193Sjb NULL, 1474179193Sjb NULL, 1475179193Sjb fasttrap_pid_getargdesc, 1476179193Sjb fasttrap_usdt_getarg, 1477179193Sjb NULL, 1478179193Sjb fasttrap_pid_destroy 1479179193Sjb}; 1480179193Sjb 1481179193Sjbstatic fasttrap_proc_t * 1482179193Sjbfasttrap_proc_lookup(pid_t pid) 1483179193Sjb{ 1484179193Sjb fasttrap_bucket_t *bucket; 1485179193Sjb fasttrap_proc_t *fprc, *new_fprc; 1486179193Sjb 1487211738Srpaulo 1488179193Sjb bucket = &fasttrap_procs.fth_table[FASTTRAP_PROCS_INDEX(pid)]; 1489179193Sjb mutex_enter(&bucket->ftb_mtx); 1490179193Sjb 1491179193Sjb for (fprc = bucket->ftb_data; fprc != NULL; fprc = fprc->ftpc_next) { 1492179193Sjb if (fprc->ftpc_pid == pid && fprc->ftpc_acount != 0) { 1493179193Sjb mutex_enter(&fprc->ftpc_mtx); 1494179193Sjb mutex_exit(&bucket->ftb_mtx); 1495179193Sjb fprc->ftpc_rcount++; 1496271001Sdelphij atomic_inc_64(&fprc->ftpc_acount); 1497179198Sjb ASSERT(fprc->ftpc_acount <= fprc->ftpc_rcount); 1498179193Sjb mutex_exit(&fprc->ftpc_mtx); 1499179193Sjb 1500179193Sjb return (fprc); 1501179193Sjb } 1502179193Sjb } 1503179193Sjb 1504179193Sjb /* 1505179193Sjb * Drop the bucket lock so we don't try to perform a sleeping 1506179193Sjb * allocation under it. 1507179193Sjb */ 1508179193Sjb mutex_exit(&bucket->ftb_mtx); 1509179193Sjb 1510179193Sjb new_fprc = kmem_zalloc(sizeof (fasttrap_proc_t), KM_SLEEP); 1511179193Sjb new_fprc->ftpc_pid = pid; 1512179193Sjb new_fprc->ftpc_rcount = 1; 1513179193Sjb new_fprc->ftpc_acount = 1; 1514297077Smav#ifndef illumos 1515211738Srpaulo mutex_init(&new_fprc->ftpc_mtx, "fasttrap proc mtx", MUTEX_DEFAULT, 1516211738Srpaulo NULL); 1517211738Srpaulo#endif 1518179193Sjb 1519179193Sjb mutex_enter(&bucket->ftb_mtx); 1520179193Sjb 1521179193Sjb /* 1522179193Sjb * Take another lap through the list to make sure a proc hasn't 1523179193Sjb * been created for this pid while we weren't under the bucket lock. 1524179193Sjb */ 1525179193Sjb for (fprc = bucket->ftb_data; fprc != NULL; fprc = fprc->ftpc_next) { 1526179193Sjb if (fprc->ftpc_pid == pid && fprc->ftpc_acount != 0) { 1527179193Sjb mutex_enter(&fprc->ftpc_mtx); 1528179193Sjb mutex_exit(&bucket->ftb_mtx); 1529179193Sjb fprc->ftpc_rcount++; 1530271001Sdelphij atomic_inc_64(&fprc->ftpc_acount); 1531179198Sjb ASSERT(fprc->ftpc_acount <= fprc->ftpc_rcount); 1532179193Sjb mutex_exit(&fprc->ftpc_mtx); 1533179193Sjb 1534179193Sjb kmem_free(new_fprc, sizeof (fasttrap_proc_t)); 1535179193Sjb 1536179193Sjb return (fprc); 1537179193Sjb } 1538179193Sjb } 1539179193Sjb 1540179193Sjb new_fprc->ftpc_next = bucket->ftb_data; 1541179193Sjb bucket->ftb_data = new_fprc; 1542179193Sjb 1543179193Sjb mutex_exit(&bucket->ftb_mtx); 1544179193Sjb 1545179193Sjb return (new_fprc); 1546179193Sjb} 1547179193Sjb 1548179193Sjbstatic void 1549179193Sjbfasttrap_proc_release(fasttrap_proc_t *proc) 1550179193Sjb{ 1551179193Sjb fasttrap_bucket_t *bucket; 1552179193Sjb fasttrap_proc_t *fprc, **fprcp; 1553179193Sjb pid_t pid = proc->ftpc_pid; 1554297077Smav#ifndef illumos 1555269342Smarkj fasttrap_scrblock_t *scrblk, *scrblktmp; 1556269342Smarkj fasttrap_scrspace_t *scrspc, *scrspctmp; 1557269342Smarkj struct proc *p; 1558269342Smarkj struct thread *td; 1559269342Smarkj#endif 1560179193Sjb 1561179193Sjb mutex_enter(&proc->ftpc_mtx); 1562179193Sjb 1563179193Sjb ASSERT(proc->ftpc_rcount != 0); 1564179198Sjb ASSERT(proc->ftpc_acount <= proc->ftpc_rcount); 1565179193Sjb 1566179193Sjb if (--proc->ftpc_rcount != 0) { 1567179193Sjb mutex_exit(&proc->ftpc_mtx); 1568179193Sjb return; 1569179193Sjb } 1570179193Sjb 1571297077Smav#ifndef illumos 1572269342Smarkj /* 1573269342Smarkj * Free all structures used to manage per-thread scratch space. 1574269342Smarkj */ 1575269342Smarkj LIST_FOREACH_SAFE(scrblk, &proc->ftpc_scrblks, ftsb_next, 1576269342Smarkj scrblktmp) { 1577269342Smarkj LIST_REMOVE(scrblk, ftsb_next); 1578269342Smarkj free(scrblk, M_SOLARIS); 1579269342Smarkj } 1580269342Smarkj LIST_FOREACH_SAFE(scrspc, &proc->ftpc_fscr, ftss_next, scrspctmp) { 1581269342Smarkj LIST_REMOVE(scrspc, ftss_next); 1582269342Smarkj free(scrspc, M_SOLARIS); 1583269342Smarkj } 1584269342Smarkj LIST_FOREACH_SAFE(scrspc, &proc->ftpc_ascr, ftss_next, scrspctmp) { 1585269342Smarkj LIST_REMOVE(scrspc, ftss_next); 1586269342Smarkj free(scrspc, M_SOLARIS); 1587269342Smarkj } 1588269342Smarkj 1589269342Smarkj if ((p = pfind(pid)) != NULL) { 1590269342Smarkj FOREACH_THREAD_IN_PROC(p, td) 1591269342Smarkj td->t_dtrace_sscr = NULL; 1592269342Smarkj PROC_UNLOCK(p); 1593269342Smarkj } 1594269342Smarkj#endif 1595269342Smarkj 1596179193Sjb mutex_exit(&proc->ftpc_mtx); 1597179193Sjb 1598179193Sjb /* 1599179193Sjb * There should definitely be no live providers associated with this 1600179193Sjb * process at this point. 1601179193Sjb */ 1602179193Sjb ASSERT(proc->ftpc_acount == 0); 1603179193Sjb 1604179193Sjb bucket = &fasttrap_procs.fth_table[FASTTRAP_PROCS_INDEX(pid)]; 1605179193Sjb mutex_enter(&bucket->ftb_mtx); 1606179193Sjb 1607179193Sjb fprcp = (fasttrap_proc_t **)&bucket->ftb_data; 1608179193Sjb while ((fprc = *fprcp) != NULL) { 1609179193Sjb if (fprc == proc) 1610179193Sjb break; 1611179193Sjb 1612179193Sjb fprcp = &fprc->ftpc_next; 1613179193Sjb } 1614179193Sjb 1615179193Sjb /* 1616179193Sjb * Something strange has happened if we can't find the proc. 1617179193Sjb */ 1618179193Sjb ASSERT(fprc != NULL); 1619179193Sjb 1620179193Sjb *fprcp = fprc->ftpc_next; 1621179193Sjb 1622179193Sjb mutex_exit(&bucket->ftb_mtx); 1623179193Sjb 1624179193Sjb kmem_free(fprc, sizeof (fasttrap_proc_t)); 1625179193Sjb} 1626179193Sjb 1627179193Sjb/* 1628179193Sjb * Lookup a fasttrap-managed provider based on its name and associated pid. 1629179193Sjb * If the pattr argument is non-NULL, this function instantiates the provider 1630179193Sjb * if it doesn't exist otherwise it returns NULL. The provider is returned 1631179193Sjb * with its lock held. 1632179193Sjb */ 1633179193Sjbstatic fasttrap_provider_t * 1634179193Sjbfasttrap_provider_lookup(pid_t pid, const char *name, 1635179193Sjb const dtrace_pattr_t *pattr) 1636179193Sjb{ 1637179193Sjb fasttrap_provider_t *fp, *new_fp = NULL; 1638179193Sjb fasttrap_bucket_t *bucket; 1639179193Sjb char provname[DTRACE_PROVNAMELEN]; 1640179193Sjb proc_t *p; 1641179193Sjb cred_t *cred; 1642179193Sjb 1643179193Sjb ASSERT(strlen(name) < sizeof (fp->ftp_name)); 1644179193Sjb ASSERT(pattr != NULL); 1645179193Sjb 1646179193Sjb bucket = &fasttrap_provs.fth_table[FASTTRAP_PROVS_INDEX(pid, name)]; 1647179193Sjb mutex_enter(&bucket->ftb_mtx); 1648179193Sjb 1649179193Sjb /* 1650179193Sjb * Take a lap through the list and return the match if we find it. 1651179193Sjb */ 1652179193Sjb for (fp = bucket->ftb_data; fp != NULL; fp = fp->ftp_next) { 1653179193Sjb if (fp->ftp_pid == pid && strcmp(fp->ftp_name, name) == 0 && 1654179193Sjb !fp->ftp_retired) { 1655179193Sjb mutex_enter(&fp->ftp_mtx); 1656179193Sjb mutex_exit(&bucket->ftb_mtx); 1657179193Sjb return (fp); 1658179193Sjb } 1659179193Sjb } 1660179193Sjb 1661179193Sjb /* 1662179193Sjb * Drop the bucket lock so we don't try to perform a sleeping 1663179193Sjb * allocation under it. 1664179193Sjb */ 1665179193Sjb mutex_exit(&bucket->ftb_mtx); 1666179193Sjb 1667179193Sjb /* 1668179193Sjb * Make sure the process exists, isn't a child created as the result 1669179193Sjb * of a vfork(2), and isn't a zombie (but may be in fork). 1670179193Sjb */ 1671211738Srpaulo if ((p = pfind(pid)) == NULL) 1672179193Sjb return (NULL); 1673179193Sjb 1674179193Sjb /* 1675179193Sjb * Increment p_dtrace_probes so that the process knows to inform us 1676179193Sjb * when it exits or execs. fasttrap_provider_free() decrements this 1677179193Sjb * when we're done with this provider. 1678179193Sjb */ 1679179193Sjb p->p_dtrace_probes++; 1680179193Sjb 1681179193Sjb /* 1682179193Sjb * Grab the credentials for this process so we have 1683179193Sjb * something to pass to dtrace_register(). 1684179193Sjb */ 1685211738Srpaulo PROC_LOCK_ASSERT(p, MA_OWNED); 1686211738Srpaulo crhold(p->p_ucred); 1687211738Srpaulo cred = p->p_ucred; 1688211738Srpaulo PROC_UNLOCK(p); 1689179193Sjb 1690179193Sjb new_fp = kmem_zalloc(sizeof (fasttrap_provider_t), KM_SLEEP); 1691179193Sjb new_fp->ftp_pid = pid; 1692179193Sjb new_fp->ftp_proc = fasttrap_proc_lookup(pid); 1693297077Smav#ifndef illumos 1694211738Srpaulo mutex_init(&new_fp->ftp_mtx, "provider mtx", MUTEX_DEFAULT, NULL); 1695211738Srpaulo mutex_init(&new_fp->ftp_cmtx, "lock on creating", MUTEX_DEFAULT, NULL); 1696211738Srpaulo#endif 1697179193Sjb 1698179193Sjb ASSERT(new_fp->ftp_proc != NULL); 1699179193Sjb 1700179193Sjb mutex_enter(&bucket->ftb_mtx); 1701179193Sjb 1702179193Sjb /* 1703179193Sjb * Take another lap through the list to make sure a provider hasn't 1704179193Sjb * been created for this pid while we weren't under the bucket lock. 1705179193Sjb */ 1706179193Sjb for (fp = bucket->ftb_data; fp != NULL; fp = fp->ftp_next) { 1707179193Sjb if (fp->ftp_pid == pid && strcmp(fp->ftp_name, name) == 0 && 1708179193Sjb !fp->ftp_retired) { 1709179193Sjb mutex_enter(&fp->ftp_mtx); 1710179193Sjb mutex_exit(&bucket->ftb_mtx); 1711179193Sjb fasttrap_provider_free(new_fp); 1712179193Sjb crfree(cred); 1713179193Sjb return (fp); 1714179193Sjb } 1715179193Sjb } 1716179193Sjb 1717179193Sjb (void) strcpy(new_fp->ftp_name, name); 1718179193Sjb 1719179193Sjb /* 1720179193Sjb * Fail and return NULL if either the provider name is too long 1721179193Sjb * or we fail to register this new provider with the DTrace 1722179193Sjb * framework. Note that this is the only place we ever construct 1723179193Sjb * the full provider name -- we keep it in pieces in the provider 1724179193Sjb * structure. 1725179193Sjb */ 1726179193Sjb if (snprintf(provname, sizeof (provname), "%s%u", name, (uint_t)pid) >= 1727179193Sjb sizeof (provname) || 1728179193Sjb dtrace_register(provname, pattr, 1729179193Sjb DTRACE_PRIV_PROC | DTRACE_PRIV_OWNER | DTRACE_PRIV_ZONEOWNER, cred, 1730179193Sjb pattr == &pid_attr ? &pid_pops : &usdt_pops, new_fp, 1731179193Sjb &new_fp->ftp_provid) != 0) { 1732179193Sjb mutex_exit(&bucket->ftb_mtx); 1733179193Sjb fasttrap_provider_free(new_fp); 1734179193Sjb crfree(cred); 1735179193Sjb return (NULL); 1736179193Sjb } 1737179193Sjb 1738179193Sjb new_fp->ftp_next = bucket->ftb_data; 1739179193Sjb bucket->ftb_data = new_fp; 1740179193Sjb 1741179193Sjb mutex_enter(&new_fp->ftp_mtx); 1742179193Sjb mutex_exit(&bucket->ftb_mtx); 1743179193Sjb 1744179193Sjb crfree(cred); 1745179193Sjb return (new_fp); 1746179193Sjb} 1747179193Sjb 1748179193Sjbstatic void 1749179193Sjbfasttrap_provider_free(fasttrap_provider_t *provider) 1750179193Sjb{ 1751179193Sjb pid_t pid = provider->ftp_pid; 1752179193Sjb proc_t *p; 1753179193Sjb 1754179193Sjb /* 1755179193Sjb * There need to be no associated enabled probes, no consumers 1756179193Sjb * creating probes, and no meta providers referencing this provider. 1757179193Sjb */ 1758179193Sjb ASSERT(provider->ftp_rcount == 0); 1759179193Sjb ASSERT(provider->ftp_ccount == 0); 1760179193Sjb ASSERT(provider->ftp_mcount == 0); 1761179193Sjb 1762179198Sjb /* 1763179198Sjb * If this provider hasn't been retired, we need to explicitly drop the 1764179198Sjb * count of active providers on the associated process structure. 1765179198Sjb */ 1766179198Sjb if (!provider->ftp_retired) { 1767271001Sdelphij atomic_dec_64(&provider->ftp_proc->ftpc_acount); 1768179198Sjb ASSERT(provider->ftp_proc->ftpc_acount < 1769179198Sjb provider->ftp_proc->ftpc_rcount); 1770179198Sjb } 1771179198Sjb 1772179193Sjb fasttrap_proc_release(provider->ftp_proc); 1773179193Sjb 1774297077Smav#ifndef illumos 1775211738Srpaulo mutex_destroy(&provider->ftp_mtx); 1776211738Srpaulo mutex_destroy(&provider->ftp_cmtx); 1777211738Srpaulo#endif 1778179193Sjb kmem_free(provider, sizeof (fasttrap_provider_t)); 1779179193Sjb 1780179193Sjb /* 1781179193Sjb * Decrement p_dtrace_probes on the process whose provider we're 1782179193Sjb * freeing. We don't have to worry about clobbering somone else's 1783179193Sjb * modifications to it because we have locked the bucket that 1784179193Sjb * corresponds to this process's hash chain in the provider hash 1785179193Sjb * table. Don't sweat it if we can't find the process. 1786179193Sjb */ 1787211738Srpaulo if ((p = pfind(pid)) == NULL) { 1788179193Sjb return; 1789179193Sjb } 1790179193Sjb 1791179193Sjb p->p_dtrace_probes--; 1792297077Smav#ifndef illumos 1793211738Srpaulo PROC_UNLOCK(p); 1794211738Srpaulo#endif 1795179193Sjb} 1796179193Sjb 1797179193Sjbstatic void 1798179193Sjbfasttrap_provider_retire(pid_t pid, const char *name, int mprov) 1799179193Sjb{ 1800179193Sjb fasttrap_provider_t *fp; 1801179193Sjb fasttrap_bucket_t *bucket; 1802179193Sjb dtrace_provider_id_t provid; 1803179193Sjb 1804179193Sjb ASSERT(strlen(name) < sizeof (fp->ftp_name)); 1805179193Sjb 1806179193Sjb bucket = &fasttrap_provs.fth_table[FASTTRAP_PROVS_INDEX(pid, name)]; 1807179193Sjb mutex_enter(&bucket->ftb_mtx); 1808179193Sjb 1809179193Sjb for (fp = bucket->ftb_data; fp != NULL; fp = fp->ftp_next) { 1810179193Sjb if (fp->ftp_pid == pid && strcmp(fp->ftp_name, name) == 0 && 1811179193Sjb !fp->ftp_retired) 1812179193Sjb break; 1813179193Sjb } 1814179193Sjb 1815179193Sjb if (fp == NULL) { 1816179193Sjb mutex_exit(&bucket->ftb_mtx); 1817179193Sjb return; 1818179193Sjb } 1819179193Sjb 1820179193Sjb mutex_enter(&fp->ftp_mtx); 1821179193Sjb ASSERT(!mprov || fp->ftp_mcount > 0); 1822179193Sjb if (mprov && --fp->ftp_mcount != 0) { 1823179193Sjb mutex_exit(&fp->ftp_mtx); 1824179193Sjb mutex_exit(&bucket->ftb_mtx); 1825179193Sjb return; 1826179193Sjb } 1827179193Sjb 1828179193Sjb /* 1829179193Sjb * Mark the provider to be removed in our post-processing step, mark it 1830179193Sjb * retired, and drop the active count on its proc. Marking it indicates 1831179193Sjb * that we should try to remove it; setting the retired flag indicates 1832179193Sjb * that we're done with this provider; dropping the active the proc 1833179193Sjb * releases our hold, and when this reaches zero (as it will during 1834179193Sjb * exit or exec) the proc and associated providers become defunct. 1835179193Sjb * 1836179193Sjb * We obviously need to take the bucket lock before the provider lock 1837179193Sjb * to perform the lookup, but we need to drop the provider lock 1838179193Sjb * before calling into the DTrace framework since we acquire the 1839179193Sjb * provider lock in callbacks invoked from the DTrace framework. The 1840179193Sjb * bucket lock therefore protects the integrity of the provider hash 1841179193Sjb * table. 1842179193Sjb */ 1843271001Sdelphij atomic_dec_64(&fp->ftp_proc->ftpc_acount); 1844179198Sjb ASSERT(fp->ftp_proc->ftpc_acount < fp->ftp_proc->ftpc_rcount); 1845179198Sjb 1846179193Sjb fp->ftp_retired = 1; 1847179193Sjb fp->ftp_marked = 1; 1848179193Sjb provid = fp->ftp_provid; 1849179193Sjb mutex_exit(&fp->ftp_mtx); 1850179193Sjb 1851179193Sjb /* 1852179193Sjb * We don't have to worry about invalidating the same provider twice 1853179193Sjb * since fasttrap_provider_lookup() will ignore provider that have 1854179193Sjb * been marked as retired. 1855179193Sjb */ 1856179193Sjb dtrace_invalidate(provid); 1857179193Sjb 1858179193Sjb mutex_exit(&bucket->ftb_mtx); 1859179193Sjb 1860179193Sjb fasttrap_pid_cleanup(); 1861179193Sjb} 1862179193Sjb 1863179193Sjbstatic int 1864179193Sjbfasttrap_uint32_cmp(const void *ap, const void *bp) 1865179193Sjb{ 1866179193Sjb return (*(const uint32_t *)ap - *(const uint32_t *)bp); 1867179193Sjb} 1868179193Sjb 1869179193Sjbstatic int 1870179193Sjbfasttrap_uint64_cmp(const void *ap, const void *bp) 1871179193Sjb{ 1872179193Sjb return (*(const uint64_t *)ap - *(const uint64_t *)bp); 1873179193Sjb} 1874179193Sjb 1875179193Sjbstatic int 1876179193Sjbfasttrap_add_probe(fasttrap_probe_spec_t *pdata) 1877179193Sjb{ 1878179193Sjb fasttrap_provider_t *provider; 1879179193Sjb fasttrap_probe_t *pp; 1880179193Sjb fasttrap_tracepoint_t *tp; 1881179193Sjb char *name; 1882211738Srpaulo int i, aframes = 0, whack; 1883179193Sjb 1884179193Sjb /* 1885179193Sjb * There needs to be at least one desired trace point. 1886179193Sjb */ 1887179193Sjb if (pdata->ftps_noffs == 0) 1888179193Sjb return (EINVAL); 1889179193Sjb 1890179193Sjb switch (pdata->ftps_type) { 1891179193Sjb case DTFTP_ENTRY: 1892179193Sjb name = "entry"; 1893179193Sjb aframes = FASTTRAP_ENTRY_AFRAMES; 1894179193Sjb break; 1895179193Sjb case DTFTP_RETURN: 1896179193Sjb name = "return"; 1897179193Sjb aframes = FASTTRAP_RETURN_AFRAMES; 1898179193Sjb break; 1899179193Sjb case DTFTP_OFFSETS: 1900179193Sjb name = NULL; 1901179193Sjb break; 1902179193Sjb default: 1903179193Sjb return (EINVAL); 1904179193Sjb } 1905179193Sjb 1906179193Sjb if ((provider = fasttrap_provider_lookup(pdata->ftps_pid, 1907179193Sjb FASTTRAP_PID_NAME, &pid_attr)) == NULL) 1908179193Sjb return (ESRCH); 1909179193Sjb 1910179193Sjb /* 1911179193Sjb * Increment this reference count to indicate that a consumer is 1912179193Sjb * actively adding a new probe associated with this provider. This 1913179193Sjb * prevents the provider from being deleted -- we'll need to check 1914179193Sjb * for pending deletions when we drop this reference count. 1915179193Sjb */ 1916179193Sjb provider->ftp_ccount++; 1917179193Sjb mutex_exit(&provider->ftp_mtx); 1918179193Sjb 1919179193Sjb /* 1920179193Sjb * Grab the creation lock to ensure consistency between calls to 1921179193Sjb * dtrace_probe_lookup() and dtrace_probe_create() in the face of 1922179193Sjb * other threads creating probes. We must drop the provider lock 1923179193Sjb * before taking this lock to avoid a three-way deadlock with the 1924179193Sjb * DTrace framework. 1925179193Sjb */ 1926179193Sjb mutex_enter(&provider->ftp_cmtx); 1927179193Sjb 1928179193Sjb if (name == NULL) { 1929179193Sjb for (i = 0; i < pdata->ftps_noffs; i++) { 1930179193Sjb char name_str[17]; 1931179193Sjb 1932179193Sjb (void) sprintf(name_str, "%llx", 1933179193Sjb (unsigned long long)pdata->ftps_offs[i]); 1934179193Sjb 1935179193Sjb if (dtrace_probe_lookup(provider->ftp_provid, 1936179193Sjb pdata->ftps_mod, pdata->ftps_func, name_str) != 0) 1937179193Sjb continue; 1938179193Sjb 1939271001Sdelphij atomic_inc_32(&fasttrap_total); 1940179193Sjb 1941179193Sjb if (fasttrap_total > fasttrap_max) { 1942271001Sdelphij atomic_dec_32(&fasttrap_total); 1943179193Sjb goto no_mem; 1944179193Sjb } 1945179193Sjb 1946179193Sjb pp = kmem_zalloc(sizeof (fasttrap_probe_t), KM_SLEEP); 1947179193Sjb 1948179193Sjb pp->ftp_prov = provider; 1949179193Sjb pp->ftp_faddr = pdata->ftps_pc; 1950179193Sjb pp->ftp_fsize = pdata->ftps_size; 1951179193Sjb pp->ftp_pid = pdata->ftps_pid; 1952179193Sjb pp->ftp_ntps = 1; 1953179193Sjb 1954179193Sjb tp = kmem_zalloc(sizeof (fasttrap_tracepoint_t), 1955179193Sjb KM_SLEEP); 1956179193Sjb 1957179193Sjb tp->ftt_proc = provider->ftp_proc; 1958179193Sjb tp->ftt_pc = pdata->ftps_offs[i] + pdata->ftps_pc; 1959179193Sjb tp->ftt_pid = pdata->ftps_pid; 1960179193Sjb 1961179193Sjb pp->ftp_tps[0].fit_tp = tp; 1962179193Sjb pp->ftp_tps[0].fit_id.fti_probe = pp; 1963179193Sjb pp->ftp_tps[0].fit_id.fti_ptype = pdata->ftps_type; 1964179193Sjb 1965179193Sjb pp->ftp_id = dtrace_probe_create(provider->ftp_provid, 1966179193Sjb pdata->ftps_mod, pdata->ftps_func, name_str, 1967179193Sjb FASTTRAP_OFFSET_AFRAMES, pp); 1968179193Sjb } 1969179193Sjb 1970179193Sjb } else if (dtrace_probe_lookup(provider->ftp_provid, pdata->ftps_mod, 1971179193Sjb pdata->ftps_func, name) == 0) { 1972179193Sjb atomic_add_32(&fasttrap_total, pdata->ftps_noffs); 1973179193Sjb 1974179193Sjb if (fasttrap_total > fasttrap_max) { 1975179193Sjb atomic_add_32(&fasttrap_total, -pdata->ftps_noffs); 1976179193Sjb goto no_mem; 1977179193Sjb } 1978179193Sjb 1979179193Sjb /* 1980179193Sjb * Make sure all tracepoint program counter values are unique. 1981179193Sjb * We later assume that each probe has exactly one tracepoint 1982179193Sjb * for a given pc. 1983179193Sjb */ 1984179193Sjb qsort(pdata->ftps_offs, pdata->ftps_noffs, 1985179193Sjb sizeof (uint64_t), fasttrap_uint64_cmp); 1986179193Sjb for (i = 1; i < pdata->ftps_noffs; i++) { 1987179193Sjb if (pdata->ftps_offs[i] > pdata->ftps_offs[i - 1]) 1988179193Sjb continue; 1989179193Sjb 1990179193Sjb atomic_add_32(&fasttrap_total, -pdata->ftps_noffs); 1991179193Sjb goto no_mem; 1992179193Sjb } 1993179193Sjb 1994179193Sjb ASSERT(pdata->ftps_noffs > 0); 1995179193Sjb pp = kmem_zalloc(offsetof(fasttrap_probe_t, 1996179193Sjb ftp_tps[pdata->ftps_noffs]), KM_SLEEP); 1997179193Sjb 1998179193Sjb pp->ftp_prov = provider; 1999179193Sjb pp->ftp_faddr = pdata->ftps_pc; 2000179193Sjb pp->ftp_fsize = pdata->ftps_size; 2001179193Sjb pp->ftp_pid = pdata->ftps_pid; 2002179193Sjb pp->ftp_ntps = pdata->ftps_noffs; 2003179193Sjb 2004179193Sjb for (i = 0; i < pdata->ftps_noffs; i++) { 2005179193Sjb tp = kmem_zalloc(sizeof (fasttrap_tracepoint_t), 2006179193Sjb KM_SLEEP); 2007179193Sjb 2008179193Sjb tp->ftt_proc = provider->ftp_proc; 2009179193Sjb tp->ftt_pc = pdata->ftps_offs[i] + pdata->ftps_pc; 2010179193Sjb tp->ftt_pid = pdata->ftps_pid; 2011179193Sjb 2012179193Sjb pp->ftp_tps[i].fit_tp = tp; 2013179193Sjb pp->ftp_tps[i].fit_id.fti_probe = pp; 2014179193Sjb pp->ftp_tps[i].fit_id.fti_ptype = pdata->ftps_type; 2015179193Sjb } 2016179193Sjb 2017179193Sjb pp->ftp_id = dtrace_probe_create(provider->ftp_provid, 2018179193Sjb pdata->ftps_mod, pdata->ftps_func, name, aframes, pp); 2019179193Sjb } 2020179193Sjb 2021179193Sjb mutex_exit(&provider->ftp_cmtx); 2022179193Sjb 2023179193Sjb /* 2024179193Sjb * We know that the provider is still valid since we incremented the 2025179193Sjb * creation reference count. If someone tried to clean up this provider 2026179193Sjb * while we were using it (e.g. because the process called exec(2) or 2027179193Sjb * exit(2)), take note of that and try to clean it up now. 2028179193Sjb */ 2029179193Sjb mutex_enter(&provider->ftp_mtx); 2030179193Sjb provider->ftp_ccount--; 2031179193Sjb whack = provider->ftp_retired; 2032179193Sjb mutex_exit(&provider->ftp_mtx); 2033179193Sjb 2034179193Sjb if (whack) 2035179193Sjb fasttrap_pid_cleanup(); 2036179193Sjb 2037179193Sjb return (0); 2038179193Sjb 2039179193Sjbno_mem: 2040179193Sjb /* 2041179193Sjb * If we've exhausted the allowable resources, we'll try to remove 2042179193Sjb * this provider to free some up. This is to cover the case where 2043179193Sjb * the user has accidentally created many more probes than was 2044179193Sjb * intended (e.g. pid123:::). 2045179193Sjb */ 2046179193Sjb mutex_exit(&provider->ftp_cmtx); 2047179193Sjb mutex_enter(&provider->ftp_mtx); 2048179193Sjb provider->ftp_ccount--; 2049179193Sjb provider->ftp_marked = 1; 2050179193Sjb mutex_exit(&provider->ftp_mtx); 2051179193Sjb 2052179193Sjb fasttrap_pid_cleanup(); 2053179193Sjb 2054179193Sjb return (ENOMEM); 2055179193Sjb} 2056179193Sjb 2057179193Sjb/*ARGSUSED*/ 2058179193Sjbstatic void * 2059179193Sjbfasttrap_meta_provide(void *arg, dtrace_helper_provdesc_t *dhpv, pid_t pid) 2060179193Sjb{ 2061179193Sjb fasttrap_provider_t *provider; 2062179193Sjb 2063179193Sjb /* 2064179193Sjb * A 32-bit unsigned integer (like a pid for example) can be 2065179193Sjb * expressed in 10 or fewer decimal digits. Make sure that we'll 2066179193Sjb * have enough space for the provider name. 2067179193Sjb */ 2068179193Sjb if (strlen(dhpv->dthpv_provname) + 10 >= 2069179193Sjb sizeof (provider->ftp_name)) { 2070211738Srpaulo printf("failed to instantiate provider %s: " 2071179193Sjb "name too long to accomodate pid", dhpv->dthpv_provname); 2072179193Sjb return (NULL); 2073179193Sjb } 2074179193Sjb 2075179193Sjb /* 2076179193Sjb * Don't let folks spoof the true pid provider. 2077179193Sjb */ 2078179193Sjb if (strcmp(dhpv->dthpv_provname, FASTTRAP_PID_NAME) == 0) { 2079211738Srpaulo printf("failed to instantiate provider %s: " 2080179193Sjb "%s is an invalid name", dhpv->dthpv_provname, 2081179193Sjb FASTTRAP_PID_NAME); 2082179193Sjb return (NULL); 2083179193Sjb } 2084179193Sjb 2085179193Sjb /* 2086179193Sjb * The highest stability class that fasttrap supports is ISA; cap 2087179193Sjb * the stability of the new provider accordingly. 2088179193Sjb */ 2089179193Sjb if (dhpv->dthpv_pattr.dtpa_provider.dtat_class > DTRACE_CLASS_ISA) 2090179193Sjb dhpv->dthpv_pattr.dtpa_provider.dtat_class = DTRACE_CLASS_ISA; 2091179193Sjb if (dhpv->dthpv_pattr.dtpa_mod.dtat_class > DTRACE_CLASS_ISA) 2092179193Sjb dhpv->dthpv_pattr.dtpa_mod.dtat_class = DTRACE_CLASS_ISA; 2093179193Sjb if (dhpv->dthpv_pattr.dtpa_func.dtat_class > DTRACE_CLASS_ISA) 2094179193Sjb dhpv->dthpv_pattr.dtpa_func.dtat_class = DTRACE_CLASS_ISA; 2095179193Sjb if (dhpv->dthpv_pattr.dtpa_name.dtat_class > DTRACE_CLASS_ISA) 2096179193Sjb dhpv->dthpv_pattr.dtpa_name.dtat_class = DTRACE_CLASS_ISA; 2097179193Sjb if (dhpv->dthpv_pattr.dtpa_args.dtat_class > DTRACE_CLASS_ISA) 2098179193Sjb dhpv->dthpv_pattr.dtpa_args.dtat_class = DTRACE_CLASS_ISA; 2099179193Sjb 2100179193Sjb if ((provider = fasttrap_provider_lookup(pid, dhpv->dthpv_provname, 2101179193Sjb &dhpv->dthpv_pattr)) == NULL) { 2102211738Srpaulo printf("failed to instantiate provider %s for " 2103179193Sjb "process %u", dhpv->dthpv_provname, (uint_t)pid); 2104179193Sjb return (NULL); 2105179193Sjb } 2106179193Sjb 2107179193Sjb /* 2108179193Sjb * Up the meta provider count so this provider isn't removed until 2109179193Sjb * the meta provider has been told to remove it. 2110179193Sjb */ 2111179193Sjb provider->ftp_mcount++; 2112179193Sjb 2113179193Sjb mutex_exit(&provider->ftp_mtx); 2114179193Sjb 2115179193Sjb return (provider); 2116179193Sjb} 2117179193Sjb 2118179193Sjb/*ARGSUSED*/ 2119179193Sjbstatic void 2120179193Sjbfasttrap_meta_create_probe(void *arg, void *parg, 2121179193Sjb dtrace_helper_probedesc_t *dhpb) 2122179193Sjb{ 2123179193Sjb fasttrap_provider_t *provider = parg; 2124179193Sjb fasttrap_probe_t *pp; 2125179193Sjb fasttrap_tracepoint_t *tp; 2126179193Sjb int i, j; 2127179193Sjb uint32_t ntps; 2128179193Sjb 2129179193Sjb /* 2130179193Sjb * Since the meta provider count is non-zero we don't have to worry 2131179193Sjb * about this provider disappearing. 2132179193Sjb */ 2133179193Sjb ASSERT(provider->ftp_mcount > 0); 2134179193Sjb 2135179193Sjb /* 2136179193Sjb * The offsets must be unique. 2137179193Sjb */ 2138179193Sjb qsort(dhpb->dthpb_offs, dhpb->dthpb_noffs, sizeof (uint32_t), 2139179193Sjb fasttrap_uint32_cmp); 2140179193Sjb for (i = 1; i < dhpb->dthpb_noffs; i++) { 2141179193Sjb if (dhpb->dthpb_base + dhpb->dthpb_offs[i] <= 2142179193Sjb dhpb->dthpb_base + dhpb->dthpb_offs[i - 1]) 2143179193Sjb return; 2144179193Sjb } 2145179193Sjb 2146179193Sjb qsort(dhpb->dthpb_enoffs, dhpb->dthpb_nenoffs, sizeof (uint32_t), 2147179193Sjb fasttrap_uint32_cmp); 2148179193Sjb for (i = 1; i < dhpb->dthpb_nenoffs; i++) { 2149179193Sjb if (dhpb->dthpb_base + dhpb->dthpb_enoffs[i] <= 2150179193Sjb dhpb->dthpb_base + dhpb->dthpb_enoffs[i - 1]) 2151179193Sjb return; 2152179193Sjb } 2153179193Sjb 2154179193Sjb /* 2155179193Sjb * Grab the creation lock to ensure consistency between calls to 2156179193Sjb * dtrace_probe_lookup() and dtrace_probe_create() in the face of 2157179193Sjb * other threads creating probes. 2158179193Sjb */ 2159179193Sjb mutex_enter(&provider->ftp_cmtx); 2160179193Sjb 2161179193Sjb if (dtrace_probe_lookup(provider->ftp_provid, dhpb->dthpb_mod, 2162179193Sjb dhpb->dthpb_func, dhpb->dthpb_name) != 0) { 2163179193Sjb mutex_exit(&provider->ftp_cmtx); 2164179193Sjb return; 2165179193Sjb } 2166179193Sjb 2167179193Sjb ntps = dhpb->dthpb_noffs + dhpb->dthpb_nenoffs; 2168179193Sjb ASSERT(ntps > 0); 2169179193Sjb 2170179193Sjb atomic_add_32(&fasttrap_total, ntps); 2171179193Sjb 2172179193Sjb if (fasttrap_total > fasttrap_max) { 2173179193Sjb atomic_add_32(&fasttrap_total, -ntps); 2174179193Sjb mutex_exit(&provider->ftp_cmtx); 2175179193Sjb return; 2176179193Sjb } 2177179193Sjb 2178179193Sjb pp = kmem_zalloc(offsetof(fasttrap_probe_t, ftp_tps[ntps]), KM_SLEEP); 2179179193Sjb 2180179193Sjb pp->ftp_prov = provider; 2181179193Sjb pp->ftp_pid = provider->ftp_pid; 2182179193Sjb pp->ftp_ntps = ntps; 2183179193Sjb pp->ftp_nargs = dhpb->dthpb_xargc; 2184179193Sjb pp->ftp_xtypes = dhpb->dthpb_xtypes; 2185179193Sjb pp->ftp_ntypes = dhpb->dthpb_ntypes; 2186179193Sjb 2187179193Sjb /* 2188179193Sjb * First create a tracepoint for each actual point of interest. 2189179193Sjb */ 2190179193Sjb for (i = 0; i < dhpb->dthpb_noffs; i++) { 2191179193Sjb tp = kmem_zalloc(sizeof (fasttrap_tracepoint_t), KM_SLEEP); 2192179193Sjb 2193179193Sjb tp->ftt_proc = provider->ftp_proc; 2194179193Sjb tp->ftt_pc = dhpb->dthpb_base + dhpb->dthpb_offs[i]; 2195179193Sjb tp->ftt_pid = provider->ftp_pid; 2196179193Sjb 2197179193Sjb pp->ftp_tps[i].fit_tp = tp; 2198179193Sjb pp->ftp_tps[i].fit_id.fti_probe = pp; 2199179193Sjb#ifdef __sparc 2200179193Sjb pp->ftp_tps[i].fit_id.fti_ptype = DTFTP_POST_OFFSETS; 2201179193Sjb#else 2202179193Sjb pp->ftp_tps[i].fit_id.fti_ptype = DTFTP_OFFSETS; 2203179193Sjb#endif 2204179193Sjb } 2205179193Sjb 2206179193Sjb /* 2207179193Sjb * Then create a tracepoint for each is-enabled point. 2208179193Sjb */ 2209179193Sjb for (j = 0; i < ntps; i++, j++) { 2210179193Sjb tp = kmem_zalloc(sizeof (fasttrap_tracepoint_t), KM_SLEEP); 2211179193Sjb 2212179193Sjb tp->ftt_proc = provider->ftp_proc; 2213179193Sjb tp->ftt_pc = dhpb->dthpb_base + dhpb->dthpb_enoffs[j]; 2214179193Sjb tp->ftt_pid = provider->ftp_pid; 2215179193Sjb 2216179193Sjb pp->ftp_tps[i].fit_tp = tp; 2217179193Sjb pp->ftp_tps[i].fit_id.fti_probe = pp; 2218179193Sjb pp->ftp_tps[i].fit_id.fti_ptype = DTFTP_IS_ENABLED; 2219179193Sjb } 2220179193Sjb 2221179193Sjb /* 2222179193Sjb * If the arguments are shuffled around we set the argument remapping 2223179193Sjb * table. Later, when the probe fires, we only remap the arguments 2224179193Sjb * if the table is non-NULL. 2225179193Sjb */ 2226179193Sjb for (i = 0; i < dhpb->dthpb_xargc; i++) { 2227179193Sjb if (dhpb->dthpb_args[i] != i) { 2228179193Sjb pp->ftp_argmap = dhpb->dthpb_args; 2229179193Sjb break; 2230179193Sjb } 2231179193Sjb } 2232179193Sjb 2233179193Sjb /* 2234179193Sjb * The probe is fully constructed -- register it with DTrace. 2235179193Sjb */ 2236179193Sjb pp->ftp_id = dtrace_probe_create(provider->ftp_provid, dhpb->dthpb_mod, 2237179193Sjb dhpb->dthpb_func, dhpb->dthpb_name, FASTTRAP_OFFSET_AFRAMES, pp); 2238179193Sjb 2239179193Sjb mutex_exit(&provider->ftp_cmtx); 2240179193Sjb} 2241179193Sjb 2242179193Sjb/*ARGSUSED*/ 2243179193Sjbstatic void 2244179193Sjbfasttrap_meta_remove(void *arg, dtrace_helper_provdesc_t *dhpv, pid_t pid) 2245179193Sjb{ 2246179193Sjb /* 2247179193Sjb * Clean up the USDT provider. There may be active consumers of the 2248179193Sjb * provider busy adding probes, no damage will actually befall the 2249179193Sjb * provider until that count has dropped to zero. This just puts 2250179193Sjb * the provider on death row. 2251179193Sjb */ 2252179193Sjb fasttrap_provider_retire(pid, dhpv->dthpv_provname, 1); 2253179193Sjb} 2254179193Sjb 2255179193Sjbstatic dtrace_mops_t fasttrap_mops = { 2256179193Sjb fasttrap_meta_create_probe, 2257179193Sjb fasttrap_meta_provide, 2258179193Sjb fasttrap_meta_remove 2259179193Sjb}; 2260179193Sjb 2261179193Sjb/*ARGSUSED*/ 2262179193Sjbstatic int 2263211738Srpaulofasttrap_open(struct cdev *dev __unused, int oflags __unused, 2264211738Srpaulo int devtype __unused, struct thread *td __unused) 2265179193Sjb{ 2266179193Sjb return (0); 2267179193Sjb} 2268179193Sjb 2269179193Sjb/*ARGSUSED*/ 2270179193Sjbstatic int 2271211738Srpaulofasttrap_ioctl(struct cdev *dev, u_long cmd, caddr_t arg, int fflag, 2272211738Srpaulo struct thread *td) 2273179193Sjb{ 2274211738Srpaulo#ifdef notyet 2275211738Srpaulo struct kinfo_proc kp; 2276211738Srpaulo const cred_t *cr = td->td_ucred; 2277211738Srpaulo#endif 2278179193Sjb if (!dtrace_attached()) 2279179193Sjb return (EAGAIN); 2280179193Sjb 2281179193Sjb if (cmd == FASTTRAPIOC_MAKEPROBE) { 2282262048Savg fasttrap_probe_spec_t *uprobe = *(fasttrap_probe_spec_t **)arg; 2283179193Sjb fasttrap_probe_spec_t *probe; 2284179193Sjb uint64_t noffs; 2285179193Sjb size_t size; 2286268734Spfg int ret, err; 2287179193Sjb 2288179193Sjb if (copyin(&uprobe->ftps_noffs, &noffs, 2289179193Sjb sizeof (uprobe->ftps_noffs))) 2290179193Sjb return (EFAULT); 2291179193Sjb 2292179193Sjb /* 2293179193Sjb * Probes must have at least one tracepoint. 2294179193Sjb */ 2295179193Sjb if (noffs == 0) 2296179193Sjb return (EINVAL); 2297179193Sjb 2298179193Sjb size = sizeof (fasttrap_probe_spec_t) + 2299179193Sjb sizeof (probe->ftps_offs[0]) * (noffs - 1); 2300179193Sjb 2301179193Sjb if (size > 1024 * 1024) 2302179193Sjb return (ENOMEM); 2303179193Sjb 2304179193Sjb probe = kmem_alloc(size, KM_SLEEP); 2305179193Sjb 2306268572Spfg if (copyin(uprobe, probe, size) != 0 || 2307268572Spfg probe->ftps_noffs != noffs) { 2308179193Sjb kmem_free(probe, size); 2309179193Sjb return (EFAULT); 2310179193Sjb } 2311179193Sjb 2312179193Sjb /* 2313179193Sjb * Verify that the function and module strings contain no 2314179193Sjb * funny characters. 2315179193Sjb */ 2316268734Spfg if (u8_validate(probe->ftps_func, strlen(probe->ftps_func), 2317268734Spfg NULL, U8_VALIDATE_ENTIRE, &err) < 0) { 2318268734Spfg ret = EINVAL; 2319268734Spfg goto err; 2320179193Sjb } 2321179193Sjb 2322268734Spfg if (u8_validate(probe->ftps_mod, strlen(probe->ftps_mod), 2323268734Spfg NULL, U8_VALIDATE_ENTIRE, &err) < 0) { 2324268734Spfg ret = EINVAL; 2325268734Spfg goto err; 2326179193Sjb } 2327179193Sjb 2328211738Srpaulo#ifdef notyet 2329179193Sjb if (!PRIV_POLICY_CHOICE(cr, PRIV_ALL, B_FALSE)) { 2330179193Sjb proc_t *p; 2331179193Sjb pid_t pid = probe->ftps_pid; 2332179193Sjb 2333297077Smav#ifdef illumos 2334179193Sjb mutex_enter(&pidlock); 2335211738Srpaulo#endif 2336179193Sjb /* 2337179193Sjb * Report an error if the process doesn't exist 2338179193Sjb * or is actively being birthed. 2339179193Sjb */ 2340211738Srpaulo p = pfind(pid); 2341211738Srpaulo if (p) 2342211738Srpaulo fill_kinfo_proc(p, &kp); 2343211738Srpaulo if (p == NULL || kp.ki_stat == SIDL) { 2344297077Smav#ifdef illumos 2345179193Sjb mutex_exit(&pidlock); 2346211738Srpaulo#endif 2347179193Sjb return (ESRCH); 2348179193Sjb } 2349297077Smav#ifdef illumos 2350179193Sjb mutex_enter(&p->p_lock); 2351179193Sjb mutex_exit(&pidlock); 2352211738Srpaulo#else 2353211738Srpaulo PROC_LOCK_ASSERT(p, MA_OWNED); 2354211738Srpaulo#endif 2355179193Sjb 2356211738Srpaulo#ifdef notyet 2357179193Sjb if ((ret = priv_proc_cred_perm(cr, p, NULL, 2358179193Sjb VREAD | VWRITE)) != 0) { 2359297077Smav#ifdef illumos 2360179193Sjb mutex_exit(&p->p_lock); 2361211738Srpaulo#else 2362211738Srpaulo PROC_UNLOCK(p); 2363211738Srpaulo#endif 2364179193Sjb return (ret); 2365179193Sjb } 2366211738Srpaulo#endif /* notyet */ 2367297077Smav#ifdef illumos 2368179193Sjb mutex_exit(&p->p_lock); 2369211738Srpaulo#else 2370211738Srpaulo PROC_UNLOCK(p); 2371211738Srpaulo#endif 2372179193Sjb } 2373211738Srpaulo#endif /* notyet */ 2374179193Sjb 2375179193Sjb ret = fasttrap_add_probe(probe); 2376179193Sjberr: 2377179193Sjb kmem_free(probe, size); 2378179193Sjb 2379179193Sjb return (ret); 2380179193Sjb 2381179193Sjb } else if (cmd == FASTTRAPIOC_GETINSTR) { 2382179193Sjb fasttrap_instr_query_t instr; 2383179193Sjb fasttrap_tracepoint_t *tp; 2384179193Sjb uint_t index; 2385297077Smav#ifdef illumos 2386179193Sjb int ret; 2387211738Srpaulo#endif 2388179193Sjb 2389297077Smav#ifdef illumos 2390179193Sjb if (copyin((void *)arg, &instr, sizeof (instr)) != 0) 2391179193Sjb return (EFAULT); 2392211738Srpaulo#endif 2393179193Sjb 2394211738Srpaulo#ifdef notyet 2395179193Sjb if (!PRIV_POLICY_CHOICE(cr, PRIV_ALL, B_FALSE)) { 2396179193Sjb proc_t *p; 2397179193Sjb pid_t pid = instr.ftiq_pid; 2398179193Sjb 2399297077Smav#ifdef illumos 2400179193Sjb mutex_enter(&pidlock); 2401211738Srpaulo#endif 2402179193Sjb /* 2403179193Sjb * Report an error if the process doesn't exist 2404179193Sjb * or is actively being birthed. 2405179193Sjb */ 2406211738Srpaulo p = pfind(pid); 2407211738Srpaulo if (p) 2408211738Srpaulo fill_kinfo_proc(p, &kp); 2409211738Srpaulo if (p == NULL || kp.ki_stat == SIDL) { 2410297077Smav#ifdef illumos 2411179193Sjb mutex_exit(&pidlock); 2412211738Srpaulo#endif 2413179193Sjb return (ESRCH); 2414179193Sjb } 2415297077Smav#ifdef illumos 2416179193Sjb mutex_enter(&p->p_lock); 2417179193Sjb mutex_exit(&pidlock); 2418211738Srpaulo#else 2419211738Srpaulo PROC_LOCK_ASSERT(p, MA_OWNED); 2420211738Srpaulo#endif 2421179193Sjb 2422211738Srpaulo#ifdef notyet 2423179193Sjb if ((ret = priv_proc_cred_perm(cr, p, NULL, 2424179193Sjb VREAD)) != 0) { 2425297077Smav#ifdef illumos 2426179193Sjb mutex_exit(&p->p_lock); 2427211738Srpaulo#else 2428211738Srpaulo PROC_UNLOCK(p); 2429211738Srpaulo#endif 2430179193Sjb return (ret); 2431179193Sjb } 2432211738Srpaulo#endif /* notyet */ 2433179193Sjb 2434297077Smav#ifdef illumos 2435179193Sjb mutex_exit(&p->p_lock); 2436211738Srpaulo#else 2437211738Srpaulo PROC_UNLOCK(p); 2438211738Srpaulo#endif 2439179193Sjb } 2440211738Srpaulo#endif /* notyet */ 2441179193Sjb 2442179193Sjb index = FASTTRAP_TPOINTS_INDEX(instr.ftiq_pid, instr.ftiq_pc); 2443179193Sjb 2444179193Sjb mutex_enter(&fasttrap_tpoints.fth_table[index].ftb_mtx); 2445179193Sjb tp = fasttrap_tpoints.fth_table[index].ftb_data; 2446179193Sjb while (tp != NULL) { 2447179193Sjb if (instr.ftiq_pid == tp->ftt_pid && 2448179193Sjb instr.ftiq_pc == tp->ftt_pc && 2449179193Sjb tp->ftt_proc->ftpc_acount != 0) 2450179193Sjb break; 2451179193Sjb 2452179193Sjb tp = tp->ftt_next; 2453179193Sjb } 2454179193Sjb 2455179193Sjb if (tp == NULL) { 2456179193Sjb mutex_exit(&fasttrap_tpoints.fth_table[index].ftb_mtx); 2457179193Sjb return (ENOENT); 2458179193Sjb } 2459179193Sjb 2460179193Sjb bcopy(&tp->ftt_instr, &instr.ftiq_instr, 2461179193Sjb sizeof (instr.ftiq_instr)); 2462179193Sjb mutex_exit(&fasttrap_tpoints.fth_table[index].ftb_mtx); 2463179193Sjb 2464179193Sjb if (copyout(&instr, (void *)arg, sizeof (instr)) != 0) 2465179193Sjb return (EFAULT); 2466179193Sjb 2467179193Sjb return (0); 2468179193Sjb } 2469179193Sjb 2470179193Sjb return (EINVAL); 2471179193Sjb} 2472179193Sjb 2473179193Sjbstatic int 2474211738Srpaulofasttrap_load(void) 2475179193Sjb{ 2476179193Sjb ulong_t nent; 2477250953Smarkj int i, ret; 2478179193Sjb 2479211738Srpaulo /* Create the /dev/dtrace/fasttrap entry. */ 2480211738Srpaulo fasttrap_cdev = make_dev(&fasttrap_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600, 2481211738Srpaulo "dtrace/fasttrap"); 2482179193Sjb 2483211738Srpaulo mtx_init(&fasttrap_cleanup_mtx, "fasttrap clean", "dtrace", MTX_DEF); 2484211738Srpaulo mutex_init(&fasttrap_count_mtx, "fasttrap count mtx", MUTEX_DEFAULT, 2485211738Srpaulo NULL); 2486179193Sjb 2487297077Smav#ifdef illumos 2488179193Sjb fasttrap_max = ddi_getprop(DDI_DEV_T_ANY, devi, DDI_PROP_DONTPASS, 2489179193Sjb "fasttrap-max-probes", FASTTRAP_MAX_DEFAULT); 2490211738Srpaulo#endif 2491179193Sjb fasttrap_total = 0; 2492179193Sjb 2493179193Sjb /* 2494179193Sjb * Conjure up the tracepoints hashtable... 2495179193Sjb */ 2496297077Smav#ifdef illumos 2497179193Sjb nent = ddi_getprop(DDI_DEV_T_ANY, devi, DDI_PROP_DONTPASS, 2498179193Sjb "fasttrap-hash-size", FASTTRAP_TPOINTS_DEFAULT_SIZE); 2499211738Srpaulo#else 2500293413Sstas nent = tpoints_hash_size; 2501211738Srpaulo#endif 2502179193Sjb 2503179193Sjb if (nent == 0 || nent > 0x1000000) 2504179193Sjb nent = FASTTRAP_TPOINTS_DEFAULT_SIZE; 2505179193Sjb 2506293413Sstas tpoints_hash_size = nent; 2507293413Sstas 2508277547Sdelphij if (ISP2(nent)) 2509179193Sjb fasttrap_tpoints.fth_nent = nent; 2510179193Sjb else 2511179193Sjb fasttrap_tpoints.fth_nent = 1 << fasttrap_highbit(nent); 2512179193Sjb ASSERT(fasttrap_tpoints.fth_nent > 0); 2513179193Sjb fasttrap_tpoints.fth_mask = fasttrap_tpoints.fth_nent - 1; 2514179193Sjb fasttrap_tpoints.fth_table = kmem_zalloc(fasttrap_tpoints.fth_nent * 2515179193Sjb sizeof (fasttrap_bucket_t), KM_SLEEP); 2516297077Smav#ifndef illumos 2517211738Srpaulo for (i = 0; i < fasttrap_tpoints.fth_nent; i++) 2518211738Srpaulo mutex_init(&fasttrap_tpoints.fth_table[i].ftb_mtx, 2519211738Srpaulo "tracepoints bucket mtx", MUTEX_DEFAULT, NULL); 2520211738Srpaulo#endif 2521179193Sjb 2522179193Sjb /* 2523179193Sjb * ... and the providers hash table... 2524179193Sjb */ 2525179193Sjb nent = FASTTRAP_PROVIDERS_DEFAULT_SIZE; 2526277547Sdelphij if (ISP2(nent)) 2527179193Sjb fasttrap_provs.fth_nent = nent; 2528179193Sjb else 2529179193Sjb fasttrap_provs.fth_nent = 1 << fasttrap_highbit(nent); 2530179193Sjb ASSERT(fasttrap_provs.fth_nent > 0); 2531179193Sjb fasttrap_provs.fth_mask = fasttrap_provs.fth_nent - 1; 2532179193Sjb fasttrap_provs.fth_table = kmem_zalloc(fasttrap_provs.fth_nent * 2533179193Sjb sizeof (fasttrap_bucket_t), KM_SLEEP); 2534297077Smav#ifndef illumos 2535211738Srpaulo for (i = 0; i < fasttrap_provs.fth_nent; i++) 2536211738Srpaulo mutex_init(&fasttrap_provs.fth_table[i].ftb_mtx, 2537211738Srpaulo "providers bucket mtx", MUTEX_DEFAULT, NULL); 2538211738Srpaulo#endif 2539179193Sjb 2540259483Sasomers ret = kproc_create(fasttrap_pid_cleanup_cb, NULL, 2541259483Sasomers &fasttrap_cleanup_proc, 0, 0, "ftcleanup"); 2542259483Sasomers if (ret != 0) { 2543259483Sasomers destroy_dev(fasttrap_cdev); 2544297077Smav#ifndef illumos 2545259483Sasomers for (i = 0; i < fasttrap_provs.fth_nent; i++) 2546259483Sasomers mutex_destroy(&fasttrap_provs.fth_table[i].ftb_mtx); 2547259483Sasomers for (i = 0; i < fasttrap_tpoints.fth_nent; i++) 2548259483Sasomers mutex_destroy(&fasttrap_tpoints.fth_table[i].ftb_mtx); 2549259483Sasomers#endif 2550259483Sasomers kmem_free(fasttrap_provs.fth_table, fasttrap_provs.fth_nent * 2551259483Sasomers sizeof (fasttrap_bucket_t)); 2552259483Sasomers mtx_destroy(&fasttrap_cleanup_mtx); 2553259483Sasomers mutex_destroy(&fasttrap_count_mtx); 2554259483Sasomers return (ret); 2555259483Sasomers } 2556259483Sasomers 2557259483Sasomers 2558179193Sjb /* 2559179193Sjb * ... and the procs hash table. 2560179193Sjb */ 2561179193Sjb nent = FASTTRAP_PROCS_DEFAULT_SIZE; 2562277547Sdelphij if (ISP2(nent)) 2563179193Sjb fasttrap_procs.fth_nent = nent; 2564179193Sjb else 2565179193Sjb fasttrap_procs.fth_nent = 1 << fasttrap_highbit(nent); 2566179193Sjb ASSERT(fasttrap_procs.fth_nent > 0); 2567179193Sjb fasttrap_procs.fth_mask = fasttrap_procs.fth_nent - 1; 2568179193Sjb fasttrap_procs.fth_table = kmem_zalloc(fasttrap_procs.fth_nent * 2569179193Sjb sizeof (fasttrap_bucket_t), KM_SLEEP); 2570297077Smav#ifndef illumos 2571211738Srpaulo for (i = 0; i < fasttrap_procs.fth_nent; i++) 2572211738Srpaulo mutex_init(&fasttrap_procs.fth_table[i].ftb_mtx, 2573211738Srpaulo "processes bucket mtx", MUTEX_DEFAULT, NULL); 2574211925Srpaulo 2575299003Smarkj rm_init(&fasttrap_tp_lock, "fasttrap tracepoint"); 2576269342Smarkj 2577269342Smarkj /* 2578269342Smarkj * This event handler must run before kdtrace_thread_dtor() since it 2579269342Smarkj * accesses the thread's struct kdtrace_thread. 2580269342Smarkj */ 2581269342Smarkj fasttrap_thread_dtor_tag = EVENTHANDLER_REGISTER(thread_dtor, 2582269342Smarkj fasttrap_thread_dtor, NULL, EVENTHANDLER_PRI_FIRST); 2583211738Srpaulo#endif 2584179193Sjb 2585253079Savg /* 2586253079Savg * Install our hooks into fork(2), exec(2), and exit(2). 2587253079Savg */ 2588253079Savg dtrace_fasttrap_fork = &fasttrap_fork; 2589253079Savg dtrace_fasttrap_exit = &fasttrap_exec_exit; 2590253079Savg dtrace_fasttrap_exec = &fasttrap_exec_exit; 2591253079Savg 2592179193Sjb (void) dtrace_meta_register("fasttrap", &fasttrap_mops, NULL, 2593179193Sjb &fasttrap_meta_id); 2594179193Sjb 2595211738Srpaulo return (0); 2596179193Sjb} 2597179193Sjb 2598179193Sjbstatic int 2599211738Srpaulofasttrap_unload(void) 2600179193Sjb{ 2601179193Sjb int i, fail = 0; 2602179193Sjb 2603179193Sjb /* 2604179193Sjb * Unregister the meta-provider to make sure no new fasttrap- 2605179193Sjb * managed providers come along while we're trying to close up 2606179193Sjb * shop. If we fail to detach, we'll need to re-register as a 2607179193Sjb * meta-provider. We can fail to unregister as a meta-provider 2608179193Sjb * if providers we manage still exist. 2609179193Sjb */ 2610179193Sjb if (fasttrap_meta_id != DTRACE_METAPROVNONE && 2611179193Sjb dtrace_meta_unregister(fasttrap_meta_id) != 0) 2612211738Srpaulo return (-1); 2613179193Sjb 2614179193Sjb /* 2615179193Sjb * Iterate over all of our providers. If there's still a process 2616179193Sjb * that corresponds to that pid, fail to detach. 2617179193Sjb */ 2618179193Sjb for (i = 0; i < fasttrap_provs.fth_nent; i++) { 2619179193Sjb fasttrap_provider_t **fpp, *fp; 2620179193Sjb fasttrap_bucket_t *bucket = &fasttrap_provs.fth_table[i]; 2621179193Sjb 2622179193Sjb mutex_enter(&bucket->ftb_mtx); 2623179193Sjb fpp = (fasttrap_provider_t **)&bucket->ftb_data; 2624179193Sjb while ((fp = *fpp) != NULL) { 2625179193Sjb /* 2626179193Sjb * Acquire and release the lock as a simple way of 2627179193Sjb * waiting for any other consumer to finish with 2628179193Sjb * this provider. A thread must first acquire the 2629179193Sjb * bucket lock so there's no chance of another thread 2630179193Sjb * blocking on the provider's lock. 2631179193Sjb */ 2632179193Sjb mutex_enter(&fp->ftp_mtx); 2633179193Sjb mutex_exit(&fp->ftp_mtx); 2634179193Sjb 2635179193Sjb if (dtrace_unregister(fp->ftp_provid) != 0) { 2636179193Sjb fail = 1; 2637179193Sjb fpp = &fp->ftp_next; 2638179193Sjb } else { 2639179193Sjb *fpp = fp->ftp_next; 2640179193Sjb fasttrap_provider_free(fp); 2641179193Sjb } 2642179193Sjb } 2643179193Sjb 2644179193Sjb mutex_exit(&bucket->ftb_mtx); 2645179193Sjb } 2646179193Sjb 2647179193Sjb if (fail) { 2648179193Sjb (void) dtrace_meta_register("fasttrap", &fasttrap_mops, NULL, 2649179193Sjb &fasttrap_meta_id); 2650179193Sjb 2651211738Srpaulo return (-1); 2652179193Sjb } 2653179193Sjb 2654259483Sasomers /* 2655259483Sasomers * Stop new processes from entering these hooks now, before the 2656259483Sasomers * fasttrap_cleanup thread runs. That way all processes will hopefully 2657259483Sasomers * be out of these hooks before we free fasttrap_provs.fth_table 2658259483Sasomers */ 2659259483Sasomers ASSERT(dtrace_fasttrap_fork == &fasttrap_fork); 2660259483Sasomers dtrace_fasttrap_fork = NULL; 2661259483Sasomers 2662259483Sasomers ASSERT(dtrace_fasttrap_exec == &fasttrap_exec_exit); 2663259483Sasomers dtrace_fasttrap_exec = NULL; 2664259483Sasomers 2665259483Sasomers ASSERT(dtrace_fasttrap_exit == &fasttrap_exec_exit); 2666259483Sasomers dtrace_fasttrap_exit = NULL; 2667259483Sasomers 2668250953Smarkj mtx_lock(&fasttrap_cleanup_mtx); 2669250953Smarkj fasttrap_cleanup_drain = 1; 2670250953Smarkj /* Wait for the cleanup thread to finish up and signal us. */ 2671250953Smarkj wakeup(&fasttrap_cleanup_cv); 2672250953Smarkj mtx_sleep(&fasttrap_cleanup_drain, &fasttrap_cleanup_mtx, 0, "ftcld", 2673250953Smarkj 0); 2674250953Smarkj fasttrap_cleanup_proc = NULL; 2675252493Smarkj mtx_destroy(&fasttrap_cleanup_mtx); 2676250953Smarkj 2677179193Sjb#ifdef DEBUG 2678179193Sjb mutex_enter(&fasttrap_count_mtx); 2679179193Sjb ASSERT(fasttrap_pid_count == 0); 2680179193Sjb mutex_exit(&fasttrap_count_mtx); 2681179193Sjb#endif 2682179193Sjb 2683297077Smav#ifndef illumos 2684269342Smarkj EVENTHANDLER_DEREGISTER(thread_dtor, fasttrap_thread_dtor_tag); 2685269342Smarkj 2686259483Sasomers for (i = 0; i < fasttrap_tpoints.fth_nent; i++) 2687259483Sasomers mutex_destroy(&fasttrap_tpoints.fth_table[i].ftb_mtx); 2688259483Sasomers for (i = 0; i < fasttrap_provs.fth_nent; i++) 2689259483Sasomers mutex_destroy(&fasttrap_provs.fth_table[i].ftb_mtx); 2690259483Sasomers for (i = 0; i < fasttrap_procs.fth_nent; i++) 2691259483Sasomers mutex_destroy(&fasttrap_procs.fth_table[i].ftb_mtx); 2692259483Sasomers#endif 2693179193Sjb kmem_free(fasttrap_tpoints.fth_table, 2694179193Sjb fasttrap_tpoints.fth_nent * sizeof (fasttrap_bucket_t)); 2695179193Sjb fasttrap_tpoints.fth_nent = 0; 2696179193Sjb 2697179193Sjb kmem_free(fasttrap_provs.fth_table, 2698179193Sjb fasttrap_provs.fth_nent * sizeof (fasttrap_bucket_t)); 2699179193Sjb fasttrap_provs.fth_nent = 0; 2700179193Sjb 2701179193Sjb kmem_free(fasttrap_procs.fth_table, 2702179193Sjb fasttrap_procs.fth_nent * sizeof (fasttrap_bucket_t)); 2703179193Sjb fasttrap_procs.fth_nent = 0; 2704179193Sjb 2705297077Smav#ifndef illumos 2706211738Srpaulo destroy_dev(fasttrap_cdev); 2707211738Srpaulo mutex_destroy(&fasttrap_count_mtx); 2708299003Smarkj rm_destroy(&fasttrap_tp_lock); 2709211738Srpaulo#endif 2710179193Sjb 2711211738Srpaulo return (0); 2712179193Sjb} 2713179193Sjb 2714211738Srpaulo/* ARGSUSED */ 2715211738Srpaulostatic int 2716211738Srpaulofasttrap_modevent(module_t mod __unused, int type, void *data __unused) 2717211738Srpaulo{ 2718211738Srpaulo int error = 0; 2719179193Sjb 2720211738Srpaulo switch (type) { 2721211738Srpaulo case MOD_LOAD: 2722211738Srpaulo break; 2723179193Sjb 2724211738Srpaulo case MOD_UNLOAD: 2725211738Srpaulo break; 2726179193Sjb 2727211738Srpaulo case MOD_SHUTDOWN: 2728211738Srpaulo break; 2729179193Sjb 2730211738Srpaulo default: 2731211738Srpaulo error = EOPNOTSUPP; 2732211738Srpaulo break; 2733211738Srpaulo } 2734211738Srpaulo return (error); 2735179193Sjb} 2736179193Sjb 2737211738SrpauloSYSINIT(fasttrap_load, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY, fasttrap_load, 2738211738Srpaulo NULL); 2739211738SrpauloSYSUNINIT(fasttrap_unload, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY, 2740211738Srpaulo fasttrap_unload, NULL); 2741211738Srpaulo 2742211738SrpauloDEV_MODULE(fasttrap, fasttrap_modevent, NULL); 2743211738SrpauloMODULE_VERSION(fasttrap, 1); 2744211738SrpauloMODULE_DEPEND(fasttrap, dtrace, 1, 1, 1); 2745211738SrpauloMODULE_DEPEND(fasttrap, opensolaris, 1, 1, 1); 2746