1 2 /*--------------------------------------------------------------------*/ 3 /*--- Thread scheduling. scheduler.c ---*/ 4 /*--------------------------------------------------------------------*/ 5 6 /* 7 This file is part of Valgrind, a dynamic binary instrumentation 8 framework. 9 10 Copyright (C) 2000-2012 Julian Seward 11 jseward (at) acm.org 12 13 This program is free software; you can redistribute it and/or 14 modify it under the terms of the GNU General Public License as 15 published by the Free Software Foundation; either version 2 of the 16 License, or (at your option) any later version. 17 18 This program is distributed in the hope that it will be useful, but 19 WITHOUT ANY WARRANTY; without even the implied warranty of 20 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 21 General Public License for more details. 22 23 You should have received a copy of the GNU General Public License 24 along with this program; if not, write to the Free Software 25 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 26 02111-1307, USA. 27 28 The GNU General Public License is contained in the file COPYING. 29 */ 30 31 /* 32 Overview 33 34 Valgrind tries to emulate the kernel's threading as closely as 35 possible. The client does all threading via the normal syscalls 36 (on Linux: clone, etc). Valgrind emulates this by creating exactly 37 the same process structure as would be created without Valgrind. 38 There are no extra threads. 39 40 The main difference is that Valgrind only allows one client thread 41 to run at once. This is controlled with the CPU Big Lock, 42 "the_BigLock". Any time a thread wants to run client code or 43 manipulate any shared state (which is anything other than its own 44 ThreadState entry), it must hold the_BigLock. 45 46 When a thread is about to block in a blocking syscall, it releases 47 the_BigLock, and re-takes it when it becomes runnable again (either 48 because the syscall finished, or we took a signal). 49 50 VG_(scheduler) therefore runs in each thread. It returns only when 51 the thread is exiting, either because it exited itself, or it was 52 told to exit by another thread. 53 54 This file is almost entirely OS-independent. The details of how 55 the OS handles threading and signalling are abstracted away and 56 implemented elsewhere. [Some of the functions have worked their 57 way back for the moment, until we do an OS port in earnest...] 58 */ 59 60 61 #include "pub_core_basics.h" 62 #include "pub_core_debuglog.h" 63 #include "pub_core_vki.h" 64 #include "pub_core_vkiscnums.h" // __NR_sched_yield 65 #include "pub_core_libcsetjmp.h" // to keep _threadstate.h happy 66 #include "pub_core_threadstate.h" 67 #include "pub_core_aspacemgr.h" 68 #include "pub_core_clreq.h" // for VG_USERREQ__* 69 #include "pub_core_dispatch.h" 70 #include "pub_core_errormgr.h" // For VG_(get_n_errs_found)() 71 #include "pub_core_gdbserver.h" // for VG_(gdbserver) and VG_(gdbserver_activity) 72 #include "pub_core_libcbase.h" 73 #include "pub_core_libcassert.h" 74 #include "pub_core_libcprint.h" 75 #include "pub_core_libcproc.h" 76 #include "pub_core_libcsignal.h" 77 #if defined(VGO_darwin) 78 #include "pub_core_mach.h" 79 #endif 80 #include "pub_core_machine.h" 81 #include "pub_core_mallocfree.h" 82 #include "pub_core_options.h" 83 #include "pub_core_replacemalloc.h" 84 #include "pub_core_signals.h" 85 #include "pub_core_stacks.h" 86 #include "pub_core_stacktrace.h" // For VG_(get_and_pp_StackTrace)() 87 #include "pub_core_syscall.h" 88 #include "pub_core_syswrap.h" 89 #include "pub_core_tooliface.h" 90 #include "pub_core_translate.h" // For VG_(translate)() 91 #include "pub_core_transtab.h" 92 #include "pub_core_debuginfo.h" // VG_(di_notify_pdb_debuginfo) 93 #include "priv_sched-lock.h" 94 #include "pub_core_scheduler.h" // self 95 #include "pub_core_redir.h" 96 97 98 /* --------------------------------------------------------------------- 99 Types and globals for the scheduler. 100 ------------------------------------------------------------------ */ 101 102 /* ThreadId and ThreadState are defined elsewhere*/ 103 104 /* Defines the thread-scheduling timeslice, in terms of the number of 105 basic blocks we attempt to run each thread for. Smaller values 106 give finer interleaving but much increased scheduling overheads. */ 107 #define SCHEDULING_QUANTUM 100000 108 109 /* If False, a fault is Valgrind-internal (ie, a bug) */ 110 Bool VG_(in_generated_code) = False; 111 112 /* 64-bit counter for the number of basic blocks done. */ 113 static ULong bbs_done = 0; 114 115 /* Counter to see if vgdb activity is to be verified. 116 When nr of bbs done reaches vgdb_next_poll, scheduler will 117 poll for gdbserver activity. VG_(force_vgdb_poll) and 118 VG_(disable_vgdb_poll) allows the valgrind core (e.g. m_gdbserver) 119 to control when the next poll will be done. */ 120 static ULong vgdb_next_poll; 121 122 /* Forwards */ 123 static void do_client_request ( ThreadId tid ); 124 static void scheduler_sanity ( ThreadId tid ); 125 static void mostly_clear_thread_record ( ThreadId tid ); 126 127 /* Stats. */ 128 static ULong n_scheduling_events_MINOR = 0; 129 static ULong n_scheduling_events_MAJOR = 0; 130 131 /* Stats: number of XIndirs, and number that missed in the fast 132 cache. */ 133 static ULong stats__n_xindirs = 0; 134 static ULong stats__n_xindir_misses = 0; 135 136 /* And 32-bit temp bins for the above, so that 32-bit platforms don't 137 have to do 64 bit incs on the hot path through 138 VG_(cp_disp_xindir). */ 139 /*global*/ UInt VG_(stats__n_xindirs_32) = 0; 140 /*global*/ UInt VG_(stats__n_xindir_misses_32) = 0; 141 142 /* Sanity checking counts. */ 143 static UInt sanity_fast_count = 0; 144 static UInt sanity_slow_count = 0; 145 146 void VG_(print_scheduler_stats)(void) 147 { 148 VG_(message)(Vg_DebugMsg, 149 "scheduler: %'llu event checks.\n", bbs_done ); 150 VG_(message)(Vg_DebugMsg, 151 "scheduler: %'llu indir transfers, %'llu misses (1 in %llu)\n", 152 stats__n_xindirs, stats__n_xindir_misses, 153 stats__n_xindirs / (stats__n_xindir_misses 154 ? stats__n_xindir_misses : 1)); 155 VG_(message)(Vg_DebugMsg, 156 "scheduler: %'llu/%'llu major/minor sched events.\n", 157 n_scheduling_events_MAJOR, n_scheduling_events_MINOR); 158 VG_(message)(Vg_DebugMsg, 159 " sanity: %d cheap, %d expensive checks.\n", 160 sanity_fast_count, sanity_slow_count ); 161 } 162 163 /* 164 * Mutual exclusion object used to serialize threads. 165 */ 166 static struct sched_lock *the_BigLock; 167 168 169 /* --------------------------------------------------------------------- 170 Helper functions for the scheduler. 171 ------------------------------------------------------------------ */ 172 173 static 174 void print_sched_event ( ThreadId tid, Char* what ) 175 { 176 VG_(message)(Vg_DebugMsg, " SCHED[%d]: %s\n", tid, what ); 177 } 178 179 /* For showing SB counts, if the user asks to see them. */ 180 #define SHOW_SBCOUNT_EVERY (20ULL * 1000 * 1000) 181 static ULong bbs_done_lastcheck = 0; 182 183 static 184 void maybe_show_sb_counts ( void ) 185 { 186 Long delta = bbs_done - bbs_done_lastcheck; 187 vg_assert(delta >= 0); 188 if (UNLIKELY(delta >= SHOW_SBCOUNT_EVERY)) { 189 VG_(umsg)("%'lld superblocks executed\n", bbs_done); 190 bbs_done_lastcheck = bbs_done; 191 } 192 } 193 194 static 195 HChar* name_of_sched_event ( UInt event ) 196 { 197 switch (event) { 198 case VEX_TRC_JMP_TINVAL: return "TINVAL"; 199 case VEX_TRC_JMP_NOREDIR: return "NOREDIR"; 200 case VEX_TRC_JMP_SIGTRAP: return "SIGTRAP"; 201 case VEX_TRC_JMP_SIGSEGV: return "SIGSEGV"; 202 case VEX_TRC_JMP_SIGBUS: return "SIGBUS"; 203 case VEX_TRC_JMP_EMWARN: return "EMWARN"; 204 case VEX_TRC_JMP_EMFAIL: return "EMFAIL"; 205 case VEX_TRC_JMP_CLIENTREQ: return "CLIENTREQ"; 206 case VEX_TRC_JMP_YIELD: return "YIELD"; 207 case VEX_TRC_JMP_NODECODE: return "NODECODE"; 208 case VEX_TRC_JMP_MAPFAIL: return "MAPFAIL"; 209 case VEX_TRC_JMP_SYS_SYSCALL: return "SYSCALL"; 210 case VEX_TRC_JMP_SYS_INT32: return "INT32"; 211 case VEX_TRC_JMP_SYS_INT128: return "INT128"; 212 case VEX_TRC_JMP_SYS_INT129: return "INT129"; 213 case VEX_TRC_JMP_SYS_INT130: return "INT130"; 214 case VEX_TRC_JMP_SYS_SYSENTER: return "SYSENTER"; 215 case VEX_TRC_JMP_BORING: return "VEX_BORING"; 216 217 case VG_TRC_BORING: return "VG_BORING"; 218 case VG_TRC_INNER_FASTMISS: return "FASTMISS"; 219 case VG_TRC_INNER_COUNTERZERO: return "COUNTERZERO"; 220 case VG_TRC_FAULT_SIGNAL: return "FAULTSIGNAL"; 221 case VG_TRC_INVARIANT_FAILED: return "INVFAILED"; 222 case VG_TRC_CHAIN_ME_TO_SLOW_EP: return "CHAIN_ME_SLOW"; 223 case VG_TRC_CHAIN_ME_TO_FAST_EP: return "CHAIN_ME_FAST"; 224 default: return "??UNKNOWN??"; 225 } 226 } 227 228 /* Allocate a completely empty ThreadState record. */ 229 ThreadId VG_(alloc_ThreadState) ( void ) 230 { 231 Int i; 232 for (i = 1; i < VG_N_THREADS; i++) { 233 if (VG_(threads)[i].status == VgTs_Empty) { 234 VG_(threads)[i].status = VgTs_Init; 235 VG_(threads)[i].exitreason = VgSrc_None; 236 return i; 237 } 238 } 239 VG_(printf)("vg_alloc_ThreadState: no free slots available\n"); 240 VG_(printf)("Increase VG_N_THREADS, rebuild and try again.\n"); 241 VG_(core_panic)("VG_N_THREADS is too low"); 242 /*NOTREACHED*/ 243 } 244 245 /* 246 Mark a thread as Runnable. This will block until the_BigLock is 247 available, so that we get exclusive access to all the shared 248 structures and the CPU. Up until we get the_BigLock, we must not 249 touch any shared state. 250 251 When this returns, we'll actually be running. 252 */ 253 void VG_(acquire_BigLock)(ThreadId tid, HChar* who) 254 { 255 ThreadState *tst; 256 257 #if 0 258 if (VG_(clo_trace_sched)) { 259 HChar buf[100]; 260 vg_assert(VG_(strlen)(who) <= 100-50); 261 VG_(sprintf)(buf, "waiting for lock (%s)", who); 262 print_sched_event(tid, buf); 263 } 264 #endif 265 266 /* First, acquire the_BigLock. We can't do anything else safely 267 prior to this point. Even doing debug printing prior to this 268 point is, technically, wrong. */ 269 VG_(acquire_BigLock_LL)(NULL); 270 271 tst = VG_(get_ThreadState)(tid); 272 273 vg_assert(tst->status != VgTs_Runnable); 274 275 tst->status = VgTs_Runnable; 276 277 if (VG_(running_tid) != VG_INVALID_THREADID) 278 VG_(printf)("tid %d found %d running\n", tid, VG_(running_tid)); 279 vg_assert(VG_(running_tid) == VG_INVALID_THREADID); 280 VG_(running_tid) = tid; 281 282 { Addr gsp = VG_(get_SP)(tid); 283 VG_(unknown_SP_update)(gsp, gsp, 0/*unknown origin*/); 284 } 285 286 if (VG_(clo_trace_sched)) { 287 HChar buf[150]; 288 vg_assert(VG_(strlen)(who) <= 150-50); 289 VG_(sprintf)(buf, " acquired lock (%s)", who); 290 print_sched_event(tid, buf); 291 } 292 } 293 294 /* 295 Set a thread into a sleeping state, and give up exclusive access to 296 the CPU. On return, the thread must be prepared to block until it 297 is ready to run again (generally this means blocking in a syscall, 298 but it may mean that we remain in a Runnable state and we're just 299 yielding the CPU to another thread). 300 */ 301 void VG_(release_BigLock)(ThreadId tid, ThreadStatus sleepstate, HChar* who) 302 { 303 ThreadState *tst = VG_(get_ThreadState)(tid); 304 305 vg_assert(tst->status == VgTs_Runnable); 306 307 vg_assert(sleepstate == VgTs_WaitSys || 308 sleepstate == VgTs_Yielding); 309 310 tst->status = sleepstate; 311 312 vg_assert(VG_(running_tid) == tid); 313 VG_(running_tid) = VG_INVALID_THREADID; 314 315 if (VG_(clo_trace_sched)) { 316 Char buf[200]; 317 vg_assert(VG_(strlen)(who) <= 200-100); 318 VG_(sprintf)(buf, "releasing lock (%s) -> %s", 319 who, VG_(name_of_ThreadStatus)(sleepstate)); 320 print_sched_event(tid, buf); 321 } 322 323 /* Release the_BigLock; this will reschedule any runnable 324 thread. */ 325 VG_(release_BigLock_LL)(NULL); 326 } 327 328 static void init_BigLock(void) 329 { 330 vg_assert(!the_BigLock); 331 the_BigLock = ML_(create_sched_lock)(); 332 } 333 334 static void deinit_BigLock(void) 335 { 336 ML_(destroy_sched_lock)(the_BigLock); 337 the_BigLock = NULL; 338 } 339 340 /* See pub_core_scheduler.h for description */ 341 void VG_(acquire_BigLock_LL) ( HChar* who ) 342 { 343 ML_(acquire_sched_lock)(the_BigLock); 344 } 345 346 /* See pub_core_scheduler.h for description */ 347 void VG_(release_BigLock_LL) ( HChar* who ) 348 { 349 ML_(release_sched_lock)(the_BigLock); 350 } 351 352 Bool VG_(owns_BigLock_LL) ( ThreadId tid ) 353 { 354 return (ML_(get_sched_lock_owner)(the_BigLock) 355 == VG_(threads)[tid].os_state.lwpid); 356 } 357 358 359 /* Clear out the ThreadState and release the semaphore. Leaves the 360 ThreadState in VgTs_Zombie state, so that it doesn't get 361 reallocated until the caller is really ready. */ 362 void VG_(exit_thread)(ThreadId tid) 363 { 364 vg_assert(VG_(is_valid_tid)(tid)); 365 vg_assert(VG_(is_running_thread)(tid)); 366 vg_assert(VG_(is_exiting)(tid)); 367 368 mostly_clear_thread_record(tid); 369 VG_(running_tid) = VG_INVALID_THREADID; 370 371 /* There should still be a valid exitreason for this thread */ 372 vg_assert(VG_(threads)[tid].exitreason != VgSrc_None); 373 374 if (VG_(clo_trace_sched)) 375 print_sched_event(tid, "release lock in VG_(exit_thread)"); 376 377 VG_(release_BigLock_LL)(NULL); 378 } 379 380 /* If 'tid' is blocked in a syscall, send it SIGVGKILL so as to get it 381 out of the syscall and onto doing the next thing, whatever that is. 382 If it isn't blocked in a syscall, has no effect on the thread. */ 383 void VG_(get_thread_out_of_syscall)(ThreadId tid) 384 { 385 vg_assert(VG_(is_valid_tid)(tid)); 386 vg_assert(!VG_(is_running_thread)(tid)); 387 388 if (VG_(threads)[tid].status == VgTs_WaitSys) { 389 if (VG_(clo_trace_signals)) { 390 VG_(message)(Vg_DebugMsg, 391 "get_thread_out_of_syscall zaps tid %d lwp %d\n", 392 tid, VG_(threads)[tid].os_state.lwpid); 393 } 394 # if defined(VGO_darwin) 395 { 396 // GrP fixme use mach primitives on darwin? 397 // GrP fixme thread_abort_safely? 398 // GrP fixme race for thread with WaitSys set but not in syscall yet? 399 extern kern_return_t thread_abort(mach_port_t); 400 thread_abort(VG_(threads)[tid].os_state.lwpid); 401 } 402 # else 403 { 404 __attribute__((unused)) 405 Int r = VG_(tkill)(VG_(threads)[tid].os_state.lwpid, VG_SIGVGKILL); 406 /* JRS 2009-Mar-20: should we assert for r==0 (tkill succeeded)? 407 I'm really not sure. Here's a race scenario which argues 408 that we shoudn't; but equally I'm not sure the scenario is 409 even possible, because of constraints caused by the question 410 of who holds the BigLock when. 411 412 Target thread tid does sys_read on a socket and blocks. This 413 function gets called, and we observe correctly that tid's 414 status is WaitSys but then for whatever reason this function 415 goes very slowly for a while. Then data arrives from 416 wherever, tid's sys_read returns, tid exits. Then we do 417 tkill on tid, but tid no longer exists; tkill returns an 418 error code and the assert fails. */ 419 /* vg_assert(r == 0); */ 420 } 421 # endif 422 } 423 } 424 425 /* 426 Yield the CPU for a short time to let some other thread run. 427 */ 428 void VG_(vg_yield)(void) 429 { 430 ThreadId tid = VG_(running_tid); 431 432 vg_assert(tid != VG_INVALID_THREADID); 433 vg_assert(VG_(threads)[tid].os_state.lwpid == VG_(gettid)()); 434 435 VG_(release_BigLock)(tid, VgTs_Yielding, "VG_(vg_yield)"); 436 437 /* 438 Tell the kernel we're yielding. 439 */ 440 VG_(do_syscall0)(__NR_sched_yield); 441 442 VG_(acquire_BigLock)(tid, "VG_(vg_yield)"); 443 } 444 445 446 /* Set the standard set of blocked signals, used whenever we're not 447 running a client syscall. */ 448 static void block_signals(void) 449 { 450 vki_sigset_t mask; 451 452 VG_(sigfillset)(&mask); 453 454 /* Don't block these because they're synchronous */ 455 VG_(sigdelset)(&mask, VKI_SIGSEGV); 456 VG_(sigdelset)(&mask, VKI_SIGBUS); 457 VG_(sigdelset)(&mask, VKI_SIGFPE); 458 VG_(sigdelset)(&mask, VKI_SIGILL); 459 VG_(sigdelset)(&mask, VKI_SIGTRAP); 460 461 /* Can't block these anyway */ 462 VG_(sigdelset)(&mask, VKI_SIGSTOP); 463 VG_(sigdelset)(&mask, VKI_SIGKILL); 464 465 VG_(sigprocmask)(VKI_SIG_SETMASK, &mask, NULL); 466 } 467 468 static void os_state_clear(ThreadState *tst) 469 { 470 tst->os_state.lwpid = 0; 471 tst->os_state.threadgroup = 0; 472 # if defined(VGO_linux) 473 /* no other fields to clear */ 474 # elif defined(VGO_darwin) 475 tst->os_state.post_mach_trap_fn = NULL; 476 tst->os_state.pthread = 0; 477 tst->os_state.func_arg = 0; 478 VG_(memset)(&tst->os_state.child_go, 0, sizeof(tst->os_state.child_go)); 479 VG_(memset)(&tst->os_state.child_done, 0, sizeof(tst->os_state.child_done)); 480 tst->os_state.wq_jmpbuf_valid = False; 481 tst->os_state.remote_port = 0; 482 tst->os_state.msgh_id = 0; 483 VG_(memset)(&tst->os_state.mach_args, 0, sizeof(tst->os_state.mach_args)); 484 # else 485 # error "Unknown OS" 486 # endif 487 } 488 489 static void os_state_init(ThreadState *tst) 490 { 491 tst->os_state.valgrind_stack_base = 0; 492 tst->os_state.valgrind_stack_init_SP = 0; 493 os_state_clear(tst); 494 } 495 496 static 497 void mostly_clear_thread_record ( ThreadId tid ) 498 { 499 vki_sigset_t savedmask; 500 501 vg_assert(tid >= 0 && tid < VG_N_THREADS); 502 VG_(cleanup_thread)(&VG_(threads)[tid].arch); 503 VG_(threads)[tid].tid = tid; 504 505 /* Leave the thread in Zombie, so that it doesn't get reallocated 506 until the caller is finally done with the thread stack. */ 507 VG_(threads)[tid].status = VgTs_Zombie; 508 509 VG_(sigemptyset)(&VG_(threads)[tid].sig_mask); 510 VG_(sigemptyset)(&VG_(threads)[tid].tmp_sig_mask); 511 512 os_state_clear(&VG_(threads)[tid]); 513 514 /* start with no altstack */ 515 VG_(threads)[tid].altstack.ss_sp = (void *)0xdeadbeef; 516 VG_(threads)[tid].altstack.ss_size = 0; 517 VG_(threads)[tid].altstack.ss_flags = VKI_SS_DISABLE; 518 519 VG_(clear_out_queued_signals)(tid, &savedmask); 520 521 VG_(threads)[tid].sched_jmpbuf_valid = False; 522 } 523 524 /* 525 Called in the child after fork. If the parent has multiple 526 threads, then we've inherited a VG_(threads) array describing them, 527 but only the thread which called fork() is actually alive in the 528 child. This functions needs to clean up all those other thread 529 structures. 530 531 Whichever tid in the parent which called fork() becomes the 532 master_tid in the child. That's because the only living slot in 533 VG_(threads) in the child after fork is VG_(threads)[tid], and it 534 would be too hard to try to re-number the thread and relocate the 535 thread state down to VG_(threads)[1]. 536 537 This function also needs to reinitialize the_BigLock, since 538 otherwise we may end up sharing its state with the parent, which 539 would be deeply confusing. 540 */ 541 static void sched_fork_cleanup(ThreadId me) 542 { 543 ThreadId tid; 544 vg_assert(VG_(running_tid) == me); 545 546 # if defined(VGO_darwin) 547 // GrP fixme hack reset Mach ports 548 VG_(mach_init)(); 549 # endif 550 551 VG_(threads)[me].os_state.lwpid = VG_(gettid)(); 552 VG_(threads)[me].os_state.threadgroup = VG_(getpid)(); 553 554 /* clear out all the unused thread slots */ 555 for (tid = 1; tid < VG_N_THREADS; tid++) { 556 if (tid != me) { 557 mostly_clear_thread_record(tid); 558 VG_(threads)[tid].status = VgTs_Empty; 559 VG_(clear_syscallInfo)(tid); 560 } 561 } 562 563 /* re-init and take the sema */ 564 deinit_BigLock(); 565 init_BigLock(); 566 VG_(acquire_BigLock_LL)(NULL); 567 } 568 569 570 /* First phase of initialisation of the scheduler. Initialise the 571 bigLock, zeroise the VG_(threads) structure and decide on the 572 ThreadId of the root thread. 573 */ 574 ThreadId VG_(scheduler_init_phase1) ( void ) 575 { 576 Int i; 577 ThreadId tid_main; 578 579 VG_(debugLog)(1,"sched","sched_init_phase1\n"); 580 581 if (VG_(clo_fair_sched) != disable_fair_sched 582 && !ML_(set_sched_lock_impl)(sched_lock_ticket) 583 && VG_(clo_fair_sched) == enable_fair_sched) 584 { 585 VG_(printf)("Error: fair scheduling is not supported on this system.\n"); 586 VG_(exit)(1); 587 } 588 589 if (VG_(clo_verbosity) > 1) { 590 VG_(message)(Vg_DebugMsg, 591 "Scheduler: using %s scheduler lock implementation.\n", 592 ML_(get_sched_lock_name)()); 593 } 594 595 init_BigLock(); 596 597 for (i = 0 /* NB; not 1 */; i < VG_N_THREADS; i++) { 598 /* Paranoia .. completely zero it out. */ 599 VG_(memset)( & VG_(threads)[i], 0, sizeof( VG_(threads)[i] ) ); 600 601 VG_(threads)[i].sig_queue = NULL; 602 603 os_state_init(&VG_(threads)[i]); 604 mostly_clear_thread_record(i); 605 606 VG_(threads)[i].status = VgTs_Empty; 607 VG_(threads)[i].client_stack_szB = 0; 608 VG_(threads)[i].client_stack_highest_word = (Addr)NULL; 609 VG_(threads)[i].err_disablement_level = 0; 610 } 611 612 tid_main = VG_(alloc_ThreadState)(); 613 614 /* Bleh. Unfortunately there are various places in the system that 615 assume that the main thread has a ThreadId of 1. 616 - Helgrind (possibly) 617 - stack overflow message in default_action() in m_signals.c 618 - definitely a lot more places 619 */ 620 vg_assert(tid_main == 1); 621 622 return tid_main; 623 } 624 625 626 /* Second phase of initialisation of the scheduler. Given the root 627 ThreadId computed by first phase of initialisation, fill in stack 628 details and acquire bigLock. Initialise the scheduler. This is 629 called at startup. The caller subsequently initialises the guest 630 state components of this main thread. 631 */ 632 void VG_(scheduler_init_phase2) ( ThreadId tid_main, 633 Addr clstack_end, 634 SizeT clstack_size ) 635 { 636 VG_(debugLog)(1,"sched","sched_init_phase2: tid_main=%d, " 637 "cls_end=0x%lx, cls_sz=%ld\n", 638 tid_main, clstack_end, clstack_size); 639 640 vg_assert(VG_IS_PAGE_ALIGNED(clstack_end+1)); 641 vg_assert(VG_IS_PAGE_ALIGNED(clstack_size)); 642 643 VG_(threads)[tid_main].client_stack_highest_word 644 = clstack_end + 1 - sizeof(UWord); 645 VG_(threads)[tid_main].client_stack_szB 646 = clstack_size; 647 648 VG_(atfork)(NULL, NULL, sched_fork_cleanup); 649 } 650 651 652 /* --------------------------------------------------------------------- 653 Helpers for running translations. 654 ------------------------------------------------------------------ */ 655 656 /* Use gcc's built-in setjmp/longjmp. longjmp must not restore signal 657 mask state, but does need to pass "val" through. jumped must be a 658 volatile UWord. */ 659 #define SCHEDSETJMP(tid, jumped, stmt) \ 660 do { \ 661 ThreadState * volatile _qq_tst = VG_(get_ThreadState)(tid); \ 662 \ 663 (jumped) = VG_MINIMAL_SETJMP(_qq_tst->sched_jmpbuf); \ 664 if ((jumped) == ((UWord)0)) { \ 665 vg_assert(!_qq_tst->sched_jmpbuf_valid); \ 666 _qq_tst->sched_jmpbuf_valid = True; \ 667 stmt; \ 668 } else if (VG_(clo_trace_sched)) \ 669 VG_(printf)("SCHEDSETJMP(line %d) tid %d, jumped=%ld\n", \ 670 __LINE__, tid, jumped); \ 671 vg_assert(_qq_tst->sched_jmpbuf_valid); \ 672 _qq_tst->sched_jmpbuf_valid = False; \ 673 } while(0) 674 675 676 /* Do various guest state alignment checks prior to running a thread. 677 Specifically, check that what we have matches Vex's guest state 678 layout requirements. See libvex.h for details, but in short the 679 requirements are: There must be no holes in between the primary 680 guest state, its two copies, and the spill area. In short, all 4 681 areas must have a 16-aligned size and be 16-aligned, and placed 682 back-to-back. */ 683 static void do_pre_run_checks ( ThreadState* tst ) 684 { 685 Addr a_vex = (Addr) & tst->arch.vex; 686 Addr a_vexsh1 = (Addr) & tst->arch.vex_shadow1; 687 Addr a_vexsh2 = (Addr) & tst->arch.vex_shadow2; 688 Addr a_spill = (Addr) & tst->arch.vex_spill; 689 UInt sz_vex = (UInt) sizeof tst->arch.vex; 690 UInt sz_vexsh1 = (UInt) sizeof tst->arch.vex_shadow1; 691 UInt sz_vexsh2 = (UInt) sizeof tst->arch.vex_shadow2; 692 UInt sz_spill = (UInt) sizeof tst->arch.vex_spill; 693 694 if (0) 695 VG_(printf)("gst %p %d, sh1 %p %d, " 696 "sh2 %p %d, spill %p %d\n", 697 (void*)a_vex, sz_vex, 698 (void*)a_vexsh1, sz_vexsh1, 699 (void*)a_vexsh2, sz_vexsh2, 700 (void*)a_spill, sz_spill ); 701 702 vg_assert(VG_IS_16_ALIGNED(sz_vex)); 703 vg_assert(VG_IS_16_ALIGNED(sz_vexsh1)); 704 vg_assert(VG_IS_16_ALIGNED(sz_vexsh2)); 705 vg_assert(VG_IS_16_ALIGNED(sz_spill)); 706 707 vg_assert(VG_IS_16_ALIGNED(a_vex)); 708 vg_assert(VG_IS_16_ALIGNED(a_vexsh1)); 709 vg_assert(VG_IS_16_ALIGNED(a_vexsh2)); 710 vg_assert(VG_IS_16_ALIGNED(a_spill)); 711 712 /* Check that the guest state and its two shadows have the same 713 size, and that there are no holes in between. The latter is 714 important because Memcheck assumes that it can reliably access 715 the shadows by indexing off a pointer to the start of the 716 primary guest state area. */ 717 vg_assert(sz_vex == sz_vexsh1); 718 vg_assert(sz_vex == sz_vexsh2); 719 vg_assert(a_vex + 1 * sz_vex == a_vexsh1); 720 vg_assert(a_vex + 2 * sz_vex == a_vexsh2); 721 /* Also check there's no hole between the second shadow area and 722 the spill area. */ 723 vg_assert(sz_spill == LibVEX_N_SPILL_BYTES); 724 vg_assert(a_vex + 3 * sz_vex == a_spill); 725 726 # if defined(VGA_x86) 727 /* x86 XMM regs must form an array, ie, have no holes in 728 between. */ 729 vg_assert( 730 (offsetof(VexGuestX86State,guest_XMM7) 731 - offsetof(VexGuestX86State,guest_XMM0)) 732 == (8/*#regs*/-1) * 16/*bytes per reg*/ 733 ); 734 vg_assert(VG_IS_16_ALIGNED(offsetof(VexGuestX86State,guest_XMM0))); 735 vg_assert(VG_IS_8_ALIGNED(offsetof(VexGuestX86State,guest_FPREG))); 736 vg_assert(8 == offsetof(VexGuestX86State,guest_EAX)); 737 vg_assert(VG_IS_4_ALIGNED(offsetof(VexGuestX86State,guest_EAX))); 738 vg_assert(VG_IS_4_ALIGNED(offsetof(VexGuestX86State,guest_EIP))); 739 # endif 740 741 # if defined(VGA_amd64) 742 /* amd64 YMM regs must form an array, ie, have no holes in 743 between. */ 744 vg_assert( 745 (offsetof(VexGuestAMD64State,guest_YMM16) 746 - offsetof(VexGuestAMD64State,guest_YMM0)) 747 == (17/*#regs*/-1) * 32/*bytes per reg*/ 748 ); 749 vg_assert(VG_IS_16_ALIGNED(offsetof(VexGuestAMD64State,guest_YMM0))); 750 vg_assert(VG_IS_8_ALIGNED(offsetof(VexGuestAMD64State,guest_FPREG))); 751 vg_assert(16 == offsetof(VexGuestAMD64State,guest_RAX)); 752 vg_assert(VG_IS_8_ALIGNED(offsetof(VexGuestAMD64State,guest_RAX))); 753 vg_assert(VG_IS_8_ALIGNED(offsetof(VexGuestAMD64State,guest_RIP))); 754 # endif 755 756 # if defined(VGA_ppc32) || defined(VGA_ppc64) 757 /* ppc guest_state vector regs must be 16 byte aligned for 758 loads/stores. This is important! */ 759 vg_assert(VG_IS_16_ALIGNED(& tst->arch.vex.guest_VSR0)); 760 vg_assert(VG_IS_16_ALIGNED(& tst->arch.vex_shadow1.guest_VSR0)); 761 vg_assert(VG_IS_16_ALIGNED(& tst->arch.vex_shadow2.guest_VSR0)); 762 /* be extra paranoid .. */ 763 vg_assert(VG_IS_16_ALIGNED(& tst->arch.vex.guest_VSR1)); 764 vg_assert(VG_IS_16_ALIGNED(& tst->arch.vex_shadow1.guest_VSR1)); 765 vg_assert(VG_IS_16_ALIGNED(& tst->arch.vex_shadow2.guest_VSR1)); 766 # endif 767 768 # if defined(VGA_arm) 769 /* arm guest_state VFP regs must be 8 byte aligned for 770 loads/stores. Let's use 16 just to be on the safe side. */ 771 vg_assert(VG_IS_16_ALIGNED(& tst->arch.vex.guest_D0)); 772 vg_assert(VG_IS_16_ALIGNED(& tst->arch.vex_shadow1.guest_D0)); 773 vg_assert(VG_IS_16_ALIGNED(& tst->arch.vex_shadow2.guest_D0)); 774 /* be extra paranoid .. */ 775 vg_assert(VG_IS_8_ALIGNED(& tst->arch.vex.guest_D1)); 776 vg_assert(VG_IS_8_ALIGNED(& tst->arch.vex_shadow1.guest_D1)); 777 vg_assert(VG_IS_8_ALIGNED(& tst->arch.vex_shadow2.guest_D1)); 778 # endif 779 780 # if defined(VGA_s390x) 781 /* no special requirements */ 782 # endif 783 784 # if defined(VGA_mips32) 785 /* no special requirements */ 786 # endif 787 } 788 789 // NO_VGDB_POLL value ensures vgdb is not polled, while 790 // VGDB_POLL_ASAP ensures that the next scheduler call 791 // will cause a poll. 792 #define NO_VGDB_POLL 0xffffffffffffffffULL 793 #define VGDB_POLL_ASAP 0x0ULL 794 795 void VG_(disable_vgdb_poll) (void ) 796 { 797 vgdb_next_poll = NO_VGDB_POLL; 798 } 799 void VG_(force_vgdb_poll) ( void ) 800 { 801 vgdb_next_poll = VGDB_POLL_ASAP; 802 } 803 804 /* Run the thread tid for a while, and return a VG_TRC_* value 805 indicating why VG_(disp_run_translations) stopped, and possibly an 806 auxiliary word. Also, only allow the thread to run for at most 807 *dispatchCtrP events. If (as is the normal case) use_alt_host_addr 808 is False, we are running ordinary redir'd translations, and we 809 should therefore start by looking up the guest next IP in TT. If 810 it is True then we ignore the guest next IP and just run from 811 alt_host_addr, which presumably points at host code for a no-redir 812 translation. 813 814 Return results are placed in two_words. two_words[0] is set to the 815 TRC. In the case where that is VG_TRC_CHAIN_ME_TO_{SLOW,FAST}_EP, 816 the address to patch is placed in two_words[1]. 817 */ 818 static 819 void run_thread_for_a_while ( /*OUT*/HWord* two_words, 820 /*MOD*/Int* dispatchCtrP, 821 ThreadId tid, 822 HWord alt_host_addr, 823 Bool use_alt_host_addr ) 824 { 825 volatile HWord jumped = 0; 826 volatile ThreadState* tst = NULL; /* stop gcc complaining */ 827 volatile Int done_this_time = 0; 828 volatile HWord host_code_addr = 0; 829 830 /* Paranoia */ 831 vg_assert(VG_(is_valid_tid)(tid)); 832 vg_assert(VG_(is_running_thread)(tid)); 833 vg_assert(!VG_(is_exiting)(tid)); 834 vg_assert(*dispatchCtrP > 0); 835 836 tst = VG_(get_ThreadState)(tid); 837 do_pre_run_checks( (ThreadState*)tst ); 838 /* end Paranoia */ 839 840 /* Futz with the XIndir stats counters. */ 841 vg_assert(VG_(stats__n_xindirs_32) == 0); 842 vg_assert(VG_(stats__n_xindir_misses_32) == 0); 843 844 /* Clear return area. */ 845 two_words[0] = two_words[1] = 0; 846 847 /* Figure out where we're starting from. */ 848 if (use_alt_host_addr) { 849 /* unusual case -- no-redir translation */ 850 host_code_addr = alt_host_addr; 851 } else { 852 /* normal case -- redir translation */ 853 UInt cno = (UInt)VG_TT_FAST_HASH((Addr)tst->arch.vex.VG_INSTR_PTR); 854 if (LIKELY(VG_(tt_fast)[cno].guest == (Addr)tst->arch.vex.VG_INSTR_PTR)) 855 host_code_addr = VG_(tt_fast)[cno].host; 856 else { 857 AddrH res = 0; 858 /* not found in VG_(tt_fast). Searching here the transtab 859 improves the performance compared to returning directly 860 to the scheduler. */ 861 Bool found = VG_(search_transtab)(&res, NULL, NULL, 862 (Addr)tst->arch.vex.VG_INSTR_PTR, 863 True/*upd cache*/ 864 ); 865 if (LIKELY(found)) { 866 host_code_addr = res; 867 } else { 868 /* At this point, we know that we intended to start at a 869 normal redir translation, but it was not found. In 870 which case we can return now claiming it's not 871 findable. */ 872 two_words[0] = VG_TRC_INNER_FASTMISS; /* hmm, is that right? */ 873 return; 874 } 875 } 876 } 877 /* We have either a no-redir or a redir translation. */ 878 vg_assert(host_code_addr != 0); /* implausible */ 879 880 /* there should be no undealt-with signals */ 881 //vg_assert(VG_(threads)[tid].siginfo.si_signo == 0); 882 883 /* Set up event counter stuff for the run. */ 884 tst->arch.vex.host_EvC_COUNTER = *dispatchCtrP; 885 tst->arch.vex.host_EvC_FAILADDR 886 = (HWord)VG_(fnptr_to_fnentry)( &VG_(disp_cp_evcheck_fail) ); 887 888 if (0) { 889 vki_sigset_t m; 890 Int i, err = VG_(sigprocmask)(VKI_SIG_SETMASK, NULL, &m); 891 vg_assert(err == 0); 892 VG_(printf)("tid %d: entering code with unblocked signals: ", tid); 893 for (i = 1; i <= _VKI_NSIG; i++) 894 if (!VG_(sigismember)(&m, i)) 895 VG_(printf)("%d ", i); 896 VG_(printf)("\n"); 897 } 898 899 /* Set up return-value area. */ 900 901 // Tell the tool this thread is about to run client code 902 VG_TRACK( start_client_code, tid, bbs_done ); 903 904 vg_assert(VG_(in_generated_code) == False); 905 VG_(in_generated_code) = True; 906 907 SCHEDSETJMP( 908 tid, 909 jumped, 910 VG_(disp_run_translations)( 911 two_words, 912 (void*)&tst->arch.vex, 913 host_code_addr 914 ) 915 ); 916 917 vg_assert(VG_(in_generated_code) == True); 918 VG_(in_generated_code) = False; 919 920 if (jumped != (HWord)0) { 921 /* We get here if the client took a fault that caused our signal 922 handler to longjmp. */ 923 vg_assert(two_words[0] == 0 && two_words[1] == 0); // correct? 924 two_words[0] = VG_TRC_FAULT_SIGNAL; 925 two_words[1] = 0; 926 block_signals(); 927 } 928 929 /* Merge the 32-bit XIndir/miss counters into the 64 bit versions, 930 and zero out the 32-bit ones in preparation for the next run of 931 generated code. */ 932 stats__n_xindirs += (ULong)VG_(stats__n_xindirs_32); 933 VG_(stats__n_xindirs_32) = 0; 934 stats__n_xindir_misses += (ULong)VG_(stats__n_xindir_misses_32); 935 VG_(stats__n_xindir_misses_32) = 0; 936 937 /* Inspect the event counter. */ 938 vg_assert((Int)tst->arch.vex.host_EvC_COUNTER >= -1); 939 vg_assert(tst->arch.vex.host_EvC_FAILADDR 940 == (HWord)VG_(fnptr_to_fnentry)( &VG_(disp_cp_evcheck_fail)) ); 941 942 done_this_time = *dispatchCtrP - ((Int)tst->arch.vex.host_EvC_COUNTER + 1); 943 944 vg_assert(done_this_time >= 0); 945 bbs_done += (ULong)done_this_time; 946 947 *dispatchCtrP -= done_this_time; 948 vg_assert(*dispatchCtrP >= 0); 949 950 // Tell the tool this thread has stopped running client code 951 VG_TRACK( stop_client_code, tid, bbs_done ); 952 953 if (bbs_done >= vgdb_next_poll) { 954 if (VG_(clo_vgdb_poll)) 955 vgdb_next_poll = bbs_done + (ULong)VG_(clo_vgdb_poll); 956 else 957 /* value was changed due to gdbserver invocation via ptrace */ 958 vgdb_next_poll = NO_VGDB_POLL; 959 if (VG_(gdbserver_activity) (tid)) 960 VG_(gdbserver) (tid); 961 } 962 963 /* TRC value and possible auxiliary patch-address word are already 964 in two_words[0] and [1] respectively, as a result of the call to 965 VG_(run_innerloop). */ 966 /* Stay sane .. */ 967 if (two_words[0] == VG_TRC_CHAIN_ME_TO_SLOW_EP 968 || two_words[0] == VG_TRC_CHAIN_ME_TO_FAST_EP) { 969 vg_assert(two_words[1] != 0); /* we have a legit patch addr */ 970 } else { 971 vg_assert(two_words[1] == 0); /* nobody messed with it */ 972 } 973 } 974 975 976 /* --------------------------------------------------------------------- 977 The scheduler proper. 978 ------------------------------------------------------------------ */ 979 980 static void handle_tt_miss ( ThreadId tid ) 981 { 982 Bool found; 983 Addr ip = VG_(get_IP)(tid); 984 985 /* Trivial event. Miss in the fast-cache. Do a full 986 lookup for it. */ 987 found = VG_(search_transtab)( NULL, NULL, NULL, 988 ip, True/*upd_fast_cache*/ ); 989 if (UNLIKELY(!found)) { 990 /* Not found; we need to request a translation. */ 991 if (VG_(translate)( tid, ip, /*debug*/False, 0/*not verbose*/, 992 bbs_done, True/*allow redirection*/ )) { 993 found = VG_(search_transtab)( NULL, NULL, NULL, 994 ip, True ); 995 vg_assert2(found, "handle_tt_miss: missing tt_fast entry"); 996 997 } else { 998 // If VG_(translate)() fails, it's because it had to throw a 999 // signal because the client jumped to a bad address. That 1000 // means that either a signal has been set up for delivery, 1001 // or the thread has been marked for termination. Either 1002 // way, we just need to go back into the scheduler loop. 1003 } 1004 } 1005 } 1006 1007 static 1008 void handle_chain_me ( ThreadId tid, void* place_to_chain, Bool toFastEP ) 1009 { 1010 Bool found = False; 1011 Addr ip = VG_(get_IP)(tid); 1012 UInt to_sNo = (UInt)-1; 1013 UInt to_tteNo = (UInt)-1; 1014 1015 found = VG_(search_transtab)( NULL, &to_sNo, &to_tteNo, 1016 ip, False/*dont_upd_fast_cache*/ ); 1017 if (!found) { 1018 /* Not found; we need to request a translation. */ 1019 if (VG_(translate)( tid, ip, /*debug*/False, 0/*not verbose*/, 1020 bbs_done, True/*allow redirection*/ )) { 1021 found = VG_(search_transtab)( NULL, &to_sNo, &to_tteNo, 1022 ip, False ); 1023 vg_assert2(found, "handle_chain_me: missing tt_fast entry"); 1024 } else { 1025 // If VG_(translate)() fails, it's because it had to throw a 1026 // signal because the client jumped to a bad address. That 1027 // means that either a signal has been set up for delivery, 1028 // or the thread has been marked for termination. Either 1029 // way, we just need to go back into the scheduler loop. 1030 return; 1031 } 1032 } 1033 vg_assert(found); 1034 vg_assert(to_sNo != -1); 1035 vg_assert(to_tteNo != -1); 1036 1037 /* So, finally we know where to patch through to. Do the patching 1038 and update the various admin tables that allow it to be undone 1039 in the case that the destination block gets deleted. */ 1040 VG_(tt_tc_do_chaining)( place_to_chain, 1041 to_sNo, to_tteNo, toFastEP ); 1042 } 1043 1044 static void handle_syscall(ThreadId tid, UInt trc) 1045 { 1046 ThreadState * volatile tst = VG_(get_ThreadState)(tid); 1047 volatile UWord jumped; 1048 1049 /* Syscall may or may not block; either way, it will be 1050 complete by the time this call returns, and we'll be 1051 runnable again. We could take a signal while the 1052 syscall runs. */ 1053 1054 if (VG_(clo_sanity_level >= 3)) 1055 VG_(am_do_sync_check)("(BEFORE SYSCALL)",__FILE__,__LINE__); 1056 1057 SCHEDSETJMP(tid, jumped, VG_(client_syscall)(tid, trc)); 1058 1059 if (VG_(clo_sanity_level >= 3)) 1060 VG_(am_do_sync_check)("(AFTER SYSCALL)",__FILE__,__LINE__); 1061 1062 if (!VG_(is_running_thread)(tid)) 1063 VG_(printf)("tid %d not running; VG_(running_tid)=%d, tid %d status %d\n", 1064 tid, VG_(running_tid), tid, tst->status); 1065 vg_assert(VG_(is_running_thread)(tid)); 1066 1067 if (jumped != (UWord)0) { 1068 block_signals(); 1069 VG_(poll_signals)(tid); 1070 } 1071 } 1072 1073 /* tid just requested a jump to the noredir version of its current 1074 program counter. So make up that translation if needed, run it, 1075 and return the resulting thread return code in two_words[]. */ 1076 static 1077 void handle_noredir_jump ( /*OUT*/HWord* two_words, 1078 /*MOD*/Int* dispatchCtrP, 1079 ThreadId tid ) 1080 { 1081 /* Clear return area. */ 1082 two_words[0] = two_words[1] = 0; 1083 1084 AddrH hcode = 0; 1085 Addr ip = VG_(get_IP)(tid); 1086 1087 Bool found = VG_(search_unredir_transtab)( &hcode, ip ); 1088 if (!found) { 1089 /* Not found; we need to request a translation. */ 1090 if (VG_(translate)( tid, ip, /*debug*/False, 0/*not verbose*/, bbs_done, 1091 False/*NO REDIRECTION*/ )) { 1092 1093 found = VG_(search_unredir_transtab)( &hcode, ip ); 1094 vg_assert2(found, "unredir translation missing after creation?!"); 1095 } else { 1096 // If VG_(translate)() fails, it's because it had to throw a 1097 // signal because the client jumped to a bad address. That 1098 // means that either a signal has been set up for delivery, 1099 // or the thread has been marked for termination. Either 1100 // way, we just need to go back into the scheduler loop. 1101 two_words[0] = VG_TRC_BORING; 1102 return; 1103 } 1104 1105 } 1106 1107 vg_assert(found); 1108 vg_assert(hcode != 0); 1109 1110 /* Otherwise run it and return the resulting VG_TRC_* value. */ 1111 vg_assert(*dispatchCtrP > 0); /* so as to guarantee progress */ 1112 run_thread_for_a_while( two_words, dispatchCtrP, tid, 1113 hcode, True/*use hcode*/ ); 1114 } 1115 1116 1117 /* 1118 Run a thread until it wants to exit. 1119 1120 We assume that the caller has already called VG_(acquire_BigLock) for 1121 us, so we own the VCPU. Also, all signals are blocked. 1122 */ 1123 VgSchedReturnCode VG_(scheduler) ( ThreadId tid ) 1124 { 1125 /* Holds the remaining size of this thread's "timeslice". */ 1126 Int dispatch_ctr = 0; 1127 1128 ThreadState *tst = VG_(get_ThreadState)(tid); 1129 static Bool vgdb_startup_action_done = False; 1130 1131 if (VG_(clo_trace_sched)) 1132 print_sched_event(tid, "entering VG_(scheduler)"); 1133 1134 /* Do vgdb initialization (but once). Only the first (main) task 1135 starting up will do the below. 1136 Initialize gdbserver earlier than at the first 1137 thread VG_(scheduler) is causing problems: 1138 * at the end of VG_(scheduler_init_phase2) : 1139 The main thread is in VgTs_Init state, but in a not yet 1140 consistent state => the thread cannot be reported to gdb 1141 (e.g. causes an assert in LibVEX_GuestX86_get_eflags when giving 1142 back the guest registers to gdb). 1143 * at end of valgrind_main, just 1144 before VG_(main_thread_wrapper_NORETURN)(1) : 1145 The main thread is still in VgTs_Init state but in a 1146 more advanced state. However, the thread state is not yet 1147 completely initialized : a.o., the os_state is not yet fully 1148 set => the thread is then not properly reported to gdb, 1149 which is then confused (causing e.g. a duplicate thread be 1150 shown, without thread id). 1151 * it would be possible to initialize gdbserver "lower" in the 1152 call stack (e.g. in VG_(main_thread_wrapper_NORETURN)) but 1153 these are platform dependent and the place at which 1154 the thread state is completely initialized is not 1155 specific anymore to the main thread (so a similar "do it only 1156 once" would be needed). 1157 1158 => a "once only" initialization here is the best compromise. */ 1159 if (!vgdb_startup_action_done) { 1160 vg_assert(tid == 1); // it must be the main thread. 1161 vgdb_startup_action_done = True; 1162 if (VG_(clo_vgdb) != Vg_VgdbNo) { 1163 /* If we have to poll, ensures we do an initial poll at first 1164 scheduler call. Otherwise, ensure no poll (unless interrupted 1165 by ptrace). */ 1166 if (VG_(clo_vgdb_poll)) 1167 VG_(force_vgdb_poll) (); 1168 else 1169 VG_(disable_vgdb_poll) (); 1170 1171 vg_assert (VG_(dyn_vgdb_error) == VG_(clo_vgdb_error)); 1172 /* As we are initializing, VG_(dyn_vgdb_error) can't have been 1173 changed yet. */ 1174 1175 VG_(gdbserver_prerun_action) (1); 1176 } else { 1177 VG_(disable_vgdb_poll) (); 1178 } 1179 } 1180 1181 /* set the proper running signal mask */ 1182 block_signals(); 1183 1184 vg_assert(VG_(is_running_thread)(tid)); 1185 1186 dispatch_ctr = SCHEDULING_QUANTUM; 1187 1188 while (!VG_(is_exiting)(tid)) { 1189 1190 vg_assert(dispatch_ctr >= 0); 1191 if (dispatch_ctr == 0) { 1192 1193 /* Our slice is done, so yield the CPU to another thread. On 1194 Linux, this doesn't sleep between sleeping and running, 1195 since that would take too much time. */ 1196 1197 /* 4 July 06: it seems that a zero-length nsleep is needed to 1198 cause async thread cancellation (canceller.c) to terminate 1199 in finite time; else it is in some kind of race/starvation 1200 situation and completion is arbitrarily delayed (although 1201 this is not a deadlock). 1202 1203 Unfortunately these sleeps cause MPI jobs not to terminate 1204 sometimes (some kind of livelock). So sleeping once 1205 every N opportunities appears to work. */ 1206 1207 /* 3 Aug 06: doing sys__nsleep works but crashes some apps. 1208 sys_yield also helps the problem, whilst not crashing apps. */ 1209 1210 VG_(release_BigLock)(tid, VgTs_Yielding, 1211 "VG_(scheduler):timeslice"); 1212 /* ------------ now we don't have The Lock ------------ */ 1213 1214 VG_(acquire_BigLock)(tid, "VG_(scheduler):timeslice"); 1215 /* ------------ now we do have The Lock ------------ */ 1216 1217 /* OK, do some relatively expensive housekeeping stuff */ 1218 scheduler_sanity(tid); 1219 VG_(sanity_check_general)(False); 1220 1221 /* Look for any pending signals for this thread, and set them up 1222 for delivery */ 1223 VG_(poll_signals)(tid); 1224 1225 if (VG_(is_exiting)(tid)) 1226 break; /* poll_signals picked up a fatal signal */ 1227 1228 /* For stats purposes only. */ 1229 n_scheduling_events_MAJOR++; 1230 1231 /* Figure out how many bbs to ask vg_run_innerloop to do. Note 1232 that it decrements the counter before testing it for zero, so 1233 that if tst->dispatch_ctr is set to N you get at most N-1 1234 iterations. Also this means that tst->dispatch_ctr must 1235 exceed zero before entering the innerloop. Also also, the 1236 decrement is done before the bb is actually run, so you 1237 always get at least one decrement even if nothing happens. */ 1238 // FIXME is this right? 1239 dispatch_ctr = SCHEDULING_QUANTUM; 1240 1241 /* paranoia ... */ 1242 vg_assert(tst->tid == tid); 1243 vg_assert(tst->os_state.lwpid == VG_(gettid)()); 1244 } 1245 1246 /* For stats purposes only. */ 1247 n_scheduling_events_MINOR++; 1248 1249 if (0) 1250 VG_(message)(Vg_DebugMsg, "thread %d: running for %d bbs\n", 1251 tid, dispatch_ctr - 1 ); 1252 1253 HWord trc[2]; /* "two_words" */ 1254 run_thread_for_a_while( &trc[0], 1255 &dispatch_ctr, 1256 tid, 0/*ignored*/, False ); 1257 1258 if (VG_(clo_trace_sched) && VG_(clo_verbosity) > 2) { 1259 HChar buf[50]; 1260 VG_(sprintf)(buf, "TRC: %s", name_of_sched_event(trc[0])); 1261 print_sched_event(tid, buf); 1262 } 1263 1264 if (trc[0] == VEX_TRC_JMP_NOREDIR) { 1265 /* If we got a request to run a no-redir version of 1266 something, do so now -- handle_noredir_jump just (creates 1267 and) runs that one translation. The flip side is that the 1268 noredir translation can't itself return another noredir 1269 request -- that would be nonsensical. It can, however, 1270 return VG_TRC_BORING, which just means keep going as 1271 normal. */ 1272 /* Note that the fact that we need to continue with a 1273 no-redir jump is not recorded anywhere else in this 1274 thread's state. So we *must* execute the block right now 1275 -- we can't fail to execute it and later resume with it, 1276 because by then we'll have forgotten the fact that it 1277 should be run as no-redir, but will get run as a normal 1278 potentially-redir'd, hence screwing up. This really ought 1279 to be cleaned up, by noting in the guest state that the 1280 next block to be executed should be no-redir. Then we can 1281 suspend and resume at any point, which isn't the case at 1282 the moment. */ 1283 handle_noredir_jump( &trc[0], 1284 &dispatch_ctr, 1285 tid ); 1286 vg_assert(trc[0] != VEX_TRC_JMP_NOREDIR); 1287 1288 /* This can't be allowed to happen, since it means the block 1289 didn't execute, and we have no way to resume-as-noredir 1290 after we get more timeslice. But I don't think it ever 1291 can, since handle_noredir_jump will assert if the counter 1292 is zero on entry. */ 1293 vg_assert(trc[0] != VG_TRC_INNER_COUNTERZERO); 1294 1295 /* A no-redir translation can't return with a chain-me 1296 request, since chaining in the no-redir cache is too 1297 complex. */ 1298 vg_assert(trc[0] != VG_TRC_CHAIN_ME_TO_SLOW_EP 1299 && trc[0] != VG_TRC_CHAIN_ME_TO_FAST_EP); 1300 } 1301 1302 switch (trc[0]) { 1303 case VEX_TRC_JMP_BORING: 1304 /* assisted dispatch, no event. Used by no-redir 1305 translations to force return to the scheduler. */ 1306 case VG_TRC_BORING: 1307 /* no special event, just keep going. */ 1308 break; 1309 1310 case VG_TRC_INNER_FASTMISS: 1311 vg_assert(dispatch_ctr > 0); 1312 handle_tt_miss(tid); 1313 break; 1314 1315 case VG_TRC_CHAIN_ME_TO_SLOW_EP: { 1316 if (0) VG_(printf)("sched: CHAIN_TO_SLOW_EP: %p\n", (void*)trc[1] ); 1317 handle_chain_me(tid, (void*)trc[1], False); 1318 break; 1319 } 1320 1321 case VG_TRC_CHAIN_ME_TO_FAST_EP: { 1322 if (0) VG_(printf)("sched: CHAIN_TO_FAST_EP: %p\n", (void*)trc[1] ); 1323 handle_chain_me(tid, (void*)trc[1], True); 1324 break; 1325 } 1326 1327 case VEX_TRC_JMP_CLIENTREQ: 1328 do_client_request(tid); 1329 break; 1330 1331 case VEX_TRC_JMP_SYS_INT128: /* x86-linux */ 1332 case VEX_TRC_JMP_SYS_INT129: /* x86-darwin */ 1333 case VEX_TRC_JMP_SYS_INT130: /* x86-darwin */ 1334 case VEX_TRC_JMP_SYS_SYSCALL: /* amd64-linux, ppc32-linux, amd64-darwin */ 1335 handle_syscall(tid, trc[0]); 1336 if (VG_(clo_sanity_level) > 2) 1337 VG_(sanity_check_general)(True); /* sanity-check every syscall */ 1338 break; 1339 1340 case VEX_TRC_JMP_YIELD: 1341 /* Explicit yield, because this thread is in a spin-lock 1342 or something. Only let the thread run for a short while 1343 longer. Because swapping to another thread is expensive, 1344 we're prepared to let this thread eat a little more CPU 1345 before swapping to another. That means that short term 1346 spins waiting for hardware to poke memory won't cause a 1347 thread swap. */ 1348 if (dispatch_ctr > 2000) 1349 dispatch_ctr = 2000; 1350 break; 1351 1352 case VG_TRC_INNER_COUNTERZERO: 1353 /* Timeslice is out. Let a new thread be scheduled. */ 1354 vg_assert(dispatch_ctr == 0); 1355 break; 1356 1357 case VG_TRC_FAULT_SIGNAL: 1358 /* Everything should be set up (either we're exiting, or 1359 about to start in a signal handler). */ 1360 break; 1361 1362 case VEX_TRC_JMP_MAPFAIL: 1363 /* Failure of arch-specific address translation (x86/amd64 1364 segment override use) */ 1365 /* jrs 2005 03 11: is this correct? */ 1366 VG_(synth_fault)(tid); 1367 break; 1368 1369 case VEX_TRC_JMP_EMWARN: { 1370 static Int counts[EmWarn_NUMBER]; 1371 static Bool counts_initted = False; 1372 VexEmWarn ew; 1373 HChar* what; 1374 Bool show; 1375 Int q; 1376 if (!counts_initted) { 1377 counts_initted = True; 1378 for (q = 0; q < EmWarn_NUMBER; q++) 1379 counts[q] = 0; 1380 } 1381 ew = (VexEmWarn)VG_(threads)[tid].arch.vex.guest_EMWARN; 1382 what = (ew < 0 || ew >= EmWarn_NUMBER) 1383 ? "unknown (?!)" 1384 : LibVEX_EmWarn_string(ew); 1385 show = (ew < 0 || ew >= EmWarn_NUMBER) 1386 ? True 1387 : counts[ew]++ < 3; 1388 if (show && VG_(clo_show_emwarns) && !VG_(clo_xml)) { 1389 VG_(message)( Vg_UserMsg, 1390 "Emulation warning: unsupported action:\n"); 1391 VG_(message)( Vg_UserMsg, " %s\n", what); 1392 VG_(get_and_pp_StackTrace)( tid, VG_(clo_backtrace_size) ); 1393 } 1394 break; 1395 } 1396 1397 case VEX_TRC_JMP_EMFAIL: { 1398 VexEmWarn ew; 1399 HChar* what; 1400 ew = (VexEmWarn)VG_(threads)[tid].arch.vex.guest_EMWARN; 1401 what = (ew < 0 || ew >= EmWarn_NUMBER) 1402 ? "unknown (?!)" 1403 : LibVEX_EmWarn_string(ew); 1404 VG_(message)( Vg_UserMsg, 1405 "Emulation fatal error -- Valgrind cannot continue:\n"); 1406 VG_(message)( Vg_UserMsg, " %s\n", what); 1407 VG_(get_and_pp_StackTrace)( tid, VG_(clo_backtrace_size) ); 1408 VG_(message)(Vg_UserMsg, "\n"); 1409 VG_(message)(Vg_UserMsg, "Valgrind has to exit now. Sorry.\n"); 1410 VG_(message)(Vg_UserMsg, "\n"); 1411 VG_(exit)(1); 1412 break; 1413 } 1414 1415 case VEX_TRC_JMP_SIGTRAP: 1416 VG_(synth_sigtrap)(tid); 1417 break; 1418 1419 case VEX_TRC_JMP_SIGSEGV: 1420 VG_(synth_fault)(tid); 1421 break; 1422 1423 case VEX_TRC_JMP_SIGBUS: 1424 VG_(synth_sigbus)(tid); 1425 break; 1426 1427 case VEX_TRC_JMP_NODECODE: { 1428 Addr addr = VG_(get_IP)(tid); 1429 1430 VG_(umsg)( 1431 "valgrind: Unrecognised instruction at address %#lx.\n", addr); 1432 VG_(get_and_pp_StackTrace)(tid, VG_(clo_backtrace_size)); 1433 #define M(a) VG_(umsg)(a "\n"); 1434 M("Your program just tried to execute an instruction that Valgrind" ); 1435 M("did not recognise. There are two possible reasons for this." ); 1436 M("1. Your program has a bug and erroneously jumped to a non-code" ); 1437 M(" location. If you are running Memcheck and you just saw a" ); 1438 M(" warning about a bad jump, it's probably your program's fault."); 1439 M("2. The instruction is legitimate but Valgrind doesn't handle it,"); 1440 M(" i.e. it's Valgrind's fault. If you think this is the case or"); 1441 M(" you are not sure, please let us know and we'll try to fix it."); 1442 M("Either way, Valgrind will now raise a SIGILL signal which will" ); 1443 M("probably kill your program." ); 1444 #undef M 1445 1446 #if defined(VGA_s390x) 1447 /* Now that the complaint is out we need to adjust the guest_IA. The 1448 reason is that -- after raising the exception -- execution will 1449 continue with the insn that follows the invalid insn. As the first 1450 2 bits of the invalid insn determine its length in the usual way, 1451 we can compute the address of the next insn here and adjust the 1452 guest_IA accordingly. This adjustment is essential and tested by 1453 none/tests/s390x/op_exception.c (which would loop forever 1454 otherwise) */ 1455 UChar byte = ((UChar *)addr)[0]; 1456 UInt insn_length = ((((byte >> 6) + 1) >> 1) + 1) << 1; 1457 Addr next_insn_addr = addr + insn_length; 1458 1459 VG_(set_IP)(tid, next_insn_addr); 1460 #endif 1461 VG_(synth_sigill)(tid, addr); 1462 break; 1463 } 1464 case VEX_TRC_JMP_TINVAL: 1465 VG_(discard_translations)( 1466 (Addr64)VG_(threads)[tid].arch.vex.guest_TISTART, 1467 VG_(threads)[tid].arch.vex.guest_TILEN, 1468 "scheduler(VEX_TRC_JMP_TINVAL)" 1469 ); 1470 if (0) 1471 VG_(printf)("dump translations done.\n"); 1472 break; 1473 1474 case VG_TRC_INVARIANT_FAILED: 1475 /* This typically happens if, after running generated code, 1476 it is detected that host CPU settings (eg, FPU/Vector 1477 control words) are not as they should be. Vex's code 1478 generation specifies the state such control words should 1479 be in on entry to Vex-generated code, and they should be 1480 unchanged on exit from it. Failure of this assertion 1481 usually means a bug in Vex's code generation. */ 1482 //{ UInt xx; 1483 // __asm__ __volatile__ ( 1484 // "\t.word 0xEEF12A10\n" // fmrx r2,fpscr 1485 // "\tmov %0, r2" : "=r"(xx) : : "r2" ); 1486 // VG_(printf)("QQQQ new fpscr = %08x\n", xx); 1487 //} 1488 vg_assert2(0, "VG_(scheduler), phase 3: " 1489 "run_innerloop detected host " 1490 "state invariant failure", trc); 1491 1492 case VEX_TRC_JMP_SYS_SYSENTER: 1493 /* Do whatever simulation is appropriate for an x86 sysenter 1494 instruction. Note that it is critical to set this thread's 1495 guest_EIP to point at the code to execute after the 1496 sysenter, since Vex-generated code will not have set it -- 1497 vex does not know what it should be. Vex sets the next 1498 address to zero, so if you don't set guest_EIP, the thread 1499 will jump to zero afterwards and probably die as a result. */ 1500 # if defined(VGP_x86_linux) 1501 vg_assert2(0, "VG_(scheduler), phase 3: " 1502 "sysenter_x86 on x86-linux is not supported"); 1503 # elif defined(VGP_x86_darwin) 1504 /* return address in client edx */ 1505 VG_(threads)[tid].arch.vex.guest_EIP 1506 = VG_(threads)[tid].arch.vex.guest_EDX; 1507 handle_syscall(tid, trc[0]); 1508 # else 1509 vg_assert2(0, "VG_(scheduler), phase 3: " 1510 "sysenter_x86 on non-x86 platform?!?!"); 1511 # endif 1512 break; 1513 1514 default: 1515 vg_assert2(0, "VG_(scheduler), phase 3: " 1516 "unexpected thread return code (%u)", trc[0]); 1517 /* NOTREACHED */ 1518 break; 1519 1520 } /* switch (trc) */ 1521 1522 if (0) 1523 maybe_show_sb_counts(); 1524 } 1525 1526 if (VG_(clo_trace_sched)) 1527 print_sched_event(tid, "exiting VG_(scheduler)"); 1528 1529 vg_assert(VG_(is_exiting)(tid)); 1530 1531 return tst->exitreason; 1532 } 1533 1534 1535 /* 1536 This causes all threads to forceably exit. They aren't actually 1537 dead by the time this returns; you need to call 1538 VG_(reap_threads)() to wait for them. 1539 */ 1540 void VG_(nuke_all_threads_except) ( ThreadId me, VgSchedReturnCode src ) 1541 { 1542 ThreadId tid; 1543 1544 vg_assert(VG_(is_running_thread)(me)); 1545 1546 for (tid = 1; tid < VG_N_THREADS; tid++) { 1547 if (tid == me 1548 || VG_(threads)[tid].status == VgTs_Empty) 1549 continue; 1550 if (0) 1551 VG_(printf)( 1552 "VG_(nuke_all_threads_except): nuking tid %d\n", tid); 1553 1554 VG_(threads)[tid].exitreason = src; 1555 if (src == VgSrc_FatalSig) 1556 VG_(threads)[tid].os_state.fatalsig = VKI_SIGKILL; 1557 VG_(get_thread_out_of_syscall)(tid); 1558 } 1559 } 1560 1561 1562 /* --------------------------------------------------------------------- 1563 Specifying shadow register values 1564 ------------------------------------------------------------------ */ 1565 1566 #if defined(VGA_x86) 1567 # define VG_CLREQ_ARGS guest_EAX 1568 # define VG_CLREQ_RET guest_EDX 1569 #elif defined(VGA_amd64) 1570 # define VG_CLREQ_ARGS guest_RAX 1571 # define VG_CLREQ_RET guest_RDX 1572 #elif defined(VGA_ppc32) || defined(VGA_ppc64) 1573 # define VG_CLREQ_ARGS guest_GPR4 1574 # define VG_CLREQ_RET guest_GPR3 1575 #elif defined(VGA_arm) 1576 # define VG_CLREQ_ARGS guest_R4 1577 # define VG_CLREQ_RET guest_R3 1578 #elif defined (VGA_s390x) 1579 # define VG_CLREQ_ARGS guest_r2 1580 # define VG_CLREQ_RET guest_r3 1581 #elif defined(VGA_mips32) 1582 # define VG_CLREQ_ARGS guest_r12 1583 # define VG_CLREQ_RET guest_r11 1584 #else 1585 # error Unknown arch 1586 #endif 1587 1588 #define CLREQ_ARGS(regs) ((regs).vex.VG_CLREQ_ARGS) 1589 #define CLREQ_RET(regs) ((regs).vex.VG_CLREQ_RET) 1590 #define O_CLREQ_RET (offsetof(VexGuestArchState, VG_CLREQ_RET)) 1591 1592 // These macros write a value to a client's thread register, and tell the 1593 // tool that it's happened (if necessary). 1594 1595 #define SET_CLREQ_RETVAL(zztid, zzval) \ 1596 do { CLREQ_RET(VG_(threads)[zztid].arch) = (zzval); \ 1597 VG_TRACK( post_reg_write, \ 1598 Vg_CoreClientReq, zztid, O_CLREQ_RET, sizeof(UWord)); \ 1599 } while (0) 1600 1601 #define SET_CLCALL_RETVAL(zztid, zzval, f) \ 1602 do { CLREQ_RET(VG_(threads)[zztid].arch) = (zzval); \ 1603 VG_TRACK( post_reg_write_clientcall_return, \ 1604 zztid, O_CLREQ_RET, sizeof(UWord), f); \ 1605 } while (0) 1606 1607 1608 /* --------------------------------------------------------------------- 1609 Handle client requests. 1610 ------------------------------------------------------------------ */ 1611 1612 // OS-specific(?) client requests 1613 static Bool os_client_request(ThreadId tid, UWord *args) 1614 { 1615 Bool handled = True; 1616 1617 vg_assert(VG_(is_running_thread)(tid)); 1618 1619 switch(args[0]) { 1620 case VG_USERREQ__LIBC_FREERES_DONE: 1621 /* This is equivalent to an exit() syscall, but we don't set the 1622 exitcode (since it might already be set) */ 1623 if (0 || VG_(clo_trace_syscalls) || VG_(clo_trace_sched)) 1624 VG_(message)(Vg_DebugMsg, 1625 "__libc_freeres() done; really quitting!\n"); 1626 VG_(threads)[tid].exitreason = VgSrc_ExitThread; 1627 break; 1628 1629 default: 1630 handled = False; 1631 break; 1632 } 1633 1634 return handled; 1635 } 1636 1637 1638 /* Do a client request for the thread tid. After the request, tid may 1639 or may not still be runnable; if not, the scheduler will have to 1640 choose a new thread to run. 1641 */ 1642 static 1643 void do_client_request ( ThreadId tid ) 1644 { 1645 UWord* arg = (UWord*)(CLREQ_ARGS(VG_(threads)[tid].arch)); 1646 UWord req_no = arg[0]; 1647 1648 if (0) 1649 VG_(printf)("req no = 0x%llx, arg = %p\n", (ULong)req_no, arg); 1650 switch (req_no) { 1651 1652 case VG_USERREQ__CLIENT_CALL0: { 1653 UWord (*f)(ThreadId) = (void*)arg[1]; 1654 if (f == NULL) 1655 VG_(message)(Vg_DebugMsg, "VG_USERREQ__CLIENT_CALL0: func=%p\n", f); 1656 else 1657 SET_CLCALL_RETVAL(tid, f ( tid ), (Addr)f); 1658 break; 1659 } 1660 case VG_USERREQ__CLIENT_CALL1: { 1661 UWord (*f)(ThreadId, UWord) = (void*)arg[1]; 1662 if (f == NULL) 1663 VG_(message)(Vg_DebugMsg, "VG_USERREQ__CLIENT_CALL1: func=%p\n", f); 1664 else 1665 SET_CLCALL_RETVAL(tid, f ( tid, arg[2] ), (Addr)f ); 1666 break; 1667 } 1668 case VG_USERREQ__CLIENT_CALL2: { 1669 UWord (*f)(ThreadId, UWord, UWord) = (void*)arg[1]; 1670 if (f == NULL) 1671 VG_(message)(Vg_DebugMsg, "VG_USERREQ__CLIENT_CALL2: func=%p\n", f); 1672 else 1673 SET_CLCALL_RETVAL(tid, f ( tid, arg[2], arg[3] ), (Addr)f ); 1674 break; 1675 } 1676 case VG_USERREQ__CLIENT_CALL3: { 1677 UWord (*f)(ThreadId, UWord, UWord, UWord) = (void*)arg[1]; 1678 if (f == NULL) 1679 VG_(message)(Vg_DebugMsg, "VG_USERREQ__CLIENT_CALL3: func=%p\n", f); 1680 else 1681 SET_CLCALL_RETVAL(tid, f ( tid, arg[2], arg[3], arg[4] ), (Addr)f ); 1682 break; 1683 } 1684 1685 // Nb: this looks like a circular definition, because it kind of is. 1686 // See comment in valgrind.h to understand what's going on. 1687 case VG_USERREQ__RUNNING_ON_VALGRIND: 1688 SET_CLREQ_RETVAL(tid, RUNNING_ON_VALGRIND+1); 1689 break; 1690 1691 case VG_USERREQ__PRINTF: { 1692 /* JRS 2010-Jan-28: this is DEPRECATED; use the 1693 _VALIST_BY_REF version instead */ 1694 if (sizeof(va_list) != sizeof(UWord)) 1695 goto va_list_casting_error_NORETURN; 1696 union { 1697 va_list vargs; 1698 unsigned long uw; 1699 } u; 1700 u.uw = (unsigned long)arg[2]; 1701 Int count = 1702 VG_(vmessage)( Vg_ClientMsg, (char *)arg[1], u.vargs ); 1703 VG_(message_flush)(); 1704 SET_CLREQ_RETVAL( tid, count ); 1705 break; 1706 } 1707 1708 case VG_USERREQ__PRINTF_BACKTRACE: { 1709 /* JRS 2010-Jan-28: this is DEPRECATED; use the 1710 _VALIST_BY_REF version instead */ 1711 if (sizeof(va_list) != sizeof(UWord)) 1712 goto va_list_casting_error_NORETURN; 1713 union { 1714 va_list vargs; 1715 unsigned long uw; 1716 } u; 1717 u.uw = (unsigned long)arg[2]; 1718 Int count = 1719 VG_(vmessage)( Vg_ClientMsg, (char *)arg[1], u.vargs ); 1720 VG_(message_flush)(); 1721 VG_(get_and_pp_StackTrace)( tid, VG_(clo_backtrace_size) ); 1722 SET_CLREQ_RETVAL( tid, count ); 1723 break; 1724 } 1725 1726 case VG_USERREQ__PRINTF_VALIST_BY_REF: { 1727 va_list* vargsp = (va_list*)arg[2]; 1728 Int count = 1729 VG_(vmessage)( Vg_ClientMsg, (char *)arg[1], *vargsp ); 1730 VG_(message_flush)(); 1731 SET_CLREQ_RETVAL( tid, count ); 1732 break; 1733 } 1734 1735 case VG_USERREQ__PRINTF_BACKTRACE_VALIST_BY_REF: { 1736 va_list* vargsp = (va_list*)arg[2]; 1737 Int count = 1738 VG_(vmessage)( Vg_ClientMsg, (char *)arg[1], *vargsp ); 1739 VG_(message_flush)(); 1740 VG_(get_and_pp_StackTrace)( tid, VG_(clo_backtrace_size) ); 1741 SET_CLREQ_RETVAL( tid, count ); 1742 break; 1743 } 1744 1745 case VG_USERREQ__INTERNAL_PRINTF_VALIST_BY_REF: { 1746 va_list* vargsp = (va_list*)arg[2]; 1747 Int count = 1748 VG_(vmessage)( Vg_DebugMsg, (char *)arg[1], *vargsp ); 1749 VG_(message_flush)(); 1750 SET_CLREQ_RETVAL( tid, count ); 1751 break; 1752 } 1753 1754 case VG_USERREQ__ADD_IFUNC_TARGET: { 1755 VG_(redir_add_ifunc_target)( arg[1], arg[2] ); 1756 SET_CLREQ_RETVAL( tid, 0); 1757 break; } 1758 1759 case VG_USERREQ__STACK_REGISTER: { 1760 UWord sid = VG_(register_stack)((Addr)arg[1], (Addr)arg[2]); 1761 SET_CLREQ_RETVAL( tid, sid ); 1762 break; } 1763 1764 case VG_USERREQ__STACK_DEREGISTER: { 1765 VG_(deregister_stack)(arg[1]); 1766 SET_CLREQ_RETVAL( tid, 0 ); /* return value is meaningless */ 1767 break; } 1768 1769 case VG_USERREQ__STACK_CHANGE: { 1770 VG_(change_stack)(arg[1], (Addr)arg[2], (Addr)arg[3]); 1771 SET_CLREQ_RETVAL( tid, 0 ); /* return value is meaningless */ 1772 break; } 1773 1774 case VG_USERREQ__GET_MALLOCFUNCS: { 1775 struct vg_mallocfunc_info *info = (struct vg_mallocfunc_info *)arg[1]; 1776 1777 info->tl_malloc = VG_(tdict).tool_malloc; 1778 info->tl_calloc = VG_(tdict).tool_calloc; 1779 info->tl_realloc = VG_(tdict).tool_realloc; 1780 info->tl_memalign = VG_(tdict).tool_memalign; 1781 info->tl___builtin_new = VG_(tdict).tool___builtin_new; 1782 info->tl___builtin_vec_new = VG_(tdict).tool___builtin_vec_new; 1783 info->tl_free = VG_(tdict).tool_free; 1784 info->tl___builtin_delete = VG_(tdict).tool___builtin_delete; 1785 info->tl___builtin_vec_delete = VG_(tdict).tool___builtin_vec_delete; 1786 info->tl_malloc_usable_size = VG_(tdict).tool_malloc_usable_size; 1787 1788 info->mallinfo = VG_(mallinfo); 1789 info->clo_trace_malloc = VG_(clo_trace_malloc); 1790 1791 SET_CLREQ_RETVAL( tid, 0 ); /* return value is meaningless */ 1792 1793 break; 1794 } 1795 1796 /* Requests from the client program */ 1797 1798 case VG_USERREQ__DISCARD_TRANSLATIONS: 1799 if (VG_(clo_verbosity) > 2) 1800 VG_(printf)( "client request: DISCARD_TRANSLATIONS," 1801 " addr %p, len %lu\n", 1802 (void*)arg[1], arg[2] ); 1803 1804 VG_(discard_translations)( 1805 arg[1], arg[2], "scheduler(VG_USERREQ__DISCARD_TRANSLATIONS)" 1806 ); 1807 1808 SET_CLREQ_RETVAL( tid, 0 ); /* return value is meaningless */ 1809 break; 1810 1811 case VG_USERREQ__COUNT_ERRORS: 1812 SET_CLREQ_RETVAL( tid, VG_(get_n_errs_found)() ); 1813 break; 1814 1815 case VG_USERREQ__LOAD_PDB_DEBUGINFO: 1816 VG_(di_notify_pdb_debuginfo)( arg[1], arg[2], arg[3], arg[4] ); 1817 SET_CLREQ_RETVAL( tid, 0 ); /* return value is meaningless */ 1818 break; 1819 1820 case VG_USERREQ__MAP_IP_TO_SRCLOC: { 1821 Addr ip = arg[1]; 1822 UChar* buf64 = (UChar*)arg[2]; 1823 1824 VG_(memset)(buf64, 0, 64); 1825 UInt linenum = 0; 1826 Bool ok = VG_(get_filename_linenum)( 1827 ip, &buf64[0], 50, NULL, 0, NULL, &linenum 1828 ); 1829 if (ok) { 1830 /* Find the terminating zero in the first 50 bytes. */ 1831 UInt i; 1832 for (i = 0; i < 50; i++) { 1833 if (buf64[i] == 0) 1834 break; 1835 } 1836 /* We must find a zero somewhere in 0 .. 49. Else 1837 VG_(get_filename_linenum) is not properly zero 1838 terminating. */ 1839 vg_assert(i < 50); 1840 VG_(sprintf)(&buf64[i], ":%u", linenum); 1841 } else { 1842 buf64[0] = 0; 1843 } 1844 1845 SET_CLREQ_RETVAL( tid, 0 ); /* return value is meaningless */ 1846 break; 1847 } 1848 1849 case VG_USERREQ__CHANGE_ERR_DISABLEMENT: { 1850 Word delta = arg[1]; 1851 vg_assert(delta == 1 || delta == -1); 1852 ThreadState* tst = VG_(get_ThreadState)(tid); 1853 vg_assert(tst); 1854 if (delta == 1 && tst->err_disablement_level < 0xFFFFFFFF) { 1855 tst->err_disablement_level++; 1856 } 1857 else 1858 if (delta == -1 && tst->err_disablement_level > 0) { 1859 tst->err_disablement_level--; 1860 } 1861 SET_CLREQ_RETVAL( tid, 0 ); /* return value is meaningless */ 1862 break; 1863 } 1864 1865 case VG_USERREQ__MALLOCLIKE_BLOCK: 1866 case VG_USERREQ__RESIZEINPLACE_BLOCK: 1867 case VG_USERREQ__FREELIKE_BLOCK: 1868 // Ignore them if the addr is NULL; otherwise pass onto the tool. 1869 if (!arg[1]) { 1870 SET_CLREQ_RETVAL( tid, 0 ); /* return value is meaningless */ 1871 break; 1872 } else { 1873 goto my_default; 1874 } 1875 1876 default: 1877 my_default: 1878 if (os_client_request(tid, arg)) { 1879 // do nothing, os_client_request() handled it 1880 } else if (VG_(needs).client_requests) { 1881 UWord ret; 1882 1883 if (VG_(clo_verbosity) > 2) 1884 VG_(printf)("client request: code %lx, addr %p, len %lu\n", 1885 arg[0], (void*)arg[1], arg[2] ); 1886 1887 if ( VG_TDICT_CALL(tool_handle_client_request, tid, arg, &ret) ) 1888 SET_CLREQ_RETVAL(tid, ret); 1889 } else { 1890 static Bool whined = False; 1891 1892 if (!whined && VG_(clo_verbosity) > 2) { 1893 // Allow for requests in core, but defined by tools, which 1894 // have 0 and 0 in their two high bytes. 1895 Char c1 = (arg[0] >> 24) & 0xff; 1896 Char c2 = (arg[0] >> 16) & 0xff; 1897 if (c1 == 0) c1 = '_'; 1898 if (c2 == 0) c2 = '_'; 1899 VG_(message)(Vg_UserMsg, "Warning:\n" 1900 " unhandled client request: 0x%lx (%c%c+0x%lx). Perhaps\n" 1901 " VG_(needs).client_requests should be set?\n", 1902 arg[0], c1, c2, arg[0] & 0xffff); 1903 whined = True; 1904 } 1905 } 1906 break; 1907 } 1908 return; 1909 1910 /*NOTREACHED*/ 1911 va_list_casting_error_NORETURN: 1912 VG_(umsg)( 1913 "Valgrind: fatal error - cannot continue: use of the deprecated\n" 1914 "client requests VG_USERREQ__PRINTF or VG_USERREQ__PRINTF_BACKTRACE\n" 1915 "on a platform where they cannot be supported. Please use the\n" 1916 "equivalent _VALIST_BY_REF versions instead.\n" 1917 "\n" 1918 "This is a binary-incompatible change in Valgrind's client request\n" 1919 "mechanism. It is unfortunate, but difficult to avoid. End-users\n" 1920 "are expected to almost never see this message. The only case in\n" 1921 "which you might see this message is if your code uses the macros\n" 1922 "VALGRIND_PRINTF or VALGRIND_PRINTF_BACKTRACE. If so, you will need\n" 1923 "to recompile such code, using the header files from this version of\n" 1924 "Valgrind, and not any previous version.\n" 1925 "\n" 1926 "If you see this mesage in any other circumstances, it is probably\n" 1927 "a bug in Valgrind. In this case, please file a bug report at\n" 1928 "\n" 1929 " http://www.valgrind.org/support/bug_reports.html\n" 1930 "\n" 1931 "Will now abort.\n" 1932 ); 1933 vg_assert(0); 1934 } 1935 1936 1937 /* --------------------------------------------------------------------- 1938 Sanity checking (permanently engaged) 1939 ------------------------------------------------------------------ */ 1940 1941 /* Internal consistency checks on the sched structures. */ 1942 static 1943 void scheduler_sanity ( ThreadId tid ) 1944 { 1945 Bool bad = False; 1946 static UInt lasttime = 0; 1947 UInt now; 1948 Int lwpid = VG_(gettid)(); 1949 1950 if (!VG_(is_running_thread)(tid)) { 1951 VG_(message)(Vg_DebugMsg, 1952 "Thread %d is supposed to be running, " 1953 "but doesn't own the_BigLock (owned by %d)\n", 1954 tid, VG_(running_tid)); 1955 bad = True; 1956 } 1957 1958 if (lwpid != VG_(threads)[tid].os_state.lwpid) { 1959 VG_(message)(Vg_DebugMsg, 1960 "Thread %d supposed to be in LWP %d, but we're actually %d\n", 1961 tid, VG_(threads)[tid].os_state.lwpid, VG_(gettid)()); 1962 bad = True; 1963 } 1964 1965 if (lwpid != ML_(get_sched_lock_owner)(the_BigLock)) { 1966 VG_(message)(Vg_DebugMsg, 1967 "Thread (LWPID) %d doesn't own the_BigLock\n", 1968 tid); 1969 bad = True; 1970 } 1971 1972 /* Periodically show the state of all threads, for debugging 1973 purposes. */ 1974 now = VG_(read_millisecond_timer)(); 1975 if (0 && (!bad) && (lasttime + 4000/*ms*/ <= now)) { 1976 lasttime = now; 1977 VG_(printf)("\n------------ Sched State at %d ms ------------\n", 1978 (Int)now); 1979 VG_(show_sched_status)(); 1980 } 1981 1982 /* core_panic also shows the sched status, which is why we don't 1983 show it above if bad==True. */ 1984 if (bad) 1985 VG_(core_panic)("scheduler_sanity: failed"); 1986 } 1987 1988 void VG_(sanity_check_general) ( Bool force_expensive ) 1989 { 1990 ThreadId tid; 1991 1992 static UInt next_slow_check_at = 1; 1993 static UInt slow_check_interval = 25; 1994 1995 if (VG_(clo_sanity_level) < 1) return; 1996 1997 /* --- First do all the tests that we can do quickly. ---*/ 1998 1999 sanity_fast_count++; 2000 2001 /* Check stuff pertaining to the memory check system. */ 2002 2003 /* Check that nobody has spuriously claimed that the first or 2004 last 16 pages of memory have become accessible [...] */ 2005 if (VG_(needs).sanity_checks) { 2006 vg_assert(VG_TDICT_CALL(tool_cheap_sanity_check)); 2007 } 2008 2009 /* --- Now some more expensive checks. ---*/ 2010 2011 /* Once every now and again, check some more expensive stuff. 2012 Gradually increase the interval between such checks so as not to 2013 burden long-running programs too much. */ 2014 if ( force_expensive 2015 || VG_(clo_sanity_level) > 1 2016 || (VG_(clo_sanity_level) == 1 2017 && sanity_fast_count == next_slow_check_at)) { 2018 2019 if (0) VG_(printf)("SLOW at %d\n", sanity_fast_count-1); 2020 2021 next_slow_check_at = sanity_fast_count - 1 + slow_check_interval; 2022 slow_check_interval++; 2023 sanity_slow_count++; 2024 2025 if (VG_(needs).sanity_checks) { 2026 vg_assert(VG_TDICT_CALL(tool_expensive_sanity_check)); 2027 } 2028 2029 /* Look for stack overruns. Visit all threads. */ 2030 for (tid = 1; tid < VG_N_THREADS; tid++) { 2031 SizeT remains; 2032 VgStack* stack; 2033 2034 if (VG_(threads)[tid].status == VgTs_Empty || 2035 VG_(threads)[tid].status == VgTs_Zombie) 2036 continue; 2037 2038 stack 2039 = (VgStack*) 2040 VG_(get_ThreadState)(tid)->os_state.valgrind_stack_base; 2041 SizeT limit 2042 = 4096; // Let's say. Checking more causes lots of L2 misses. 2043 remains 2044 = VG_(am_get_VgStack_unused_szB)(stack, limit); 2045 if (remains < limit) 2046 VG_(message)(Vg_DebugMsg, 2047 "WARNING: Thread %d is within %ld bytes " 2048 "of running out of stack!\n", 2049 tid, remains); 2050 } 2051 } 2052 2053 if (VG_(clo_sanity_level) > 1) { 2054 /* Check sanity of the low-level memory manager. Note that bugs 2055 in the client's code can cause this to fail, so we don't do 2056 this check unless specially asked for. And because it's 2057 potentially very expensive. */ 2058 VG_(sanity_check_malloc_all)(); 2059 } 2060 } 2061 2062 /*--------------------------------------------------------------------*/ 2063 /*--- end ---*/ 2064 /*--------------------------------------------------------------------*/ 2065
