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) 2000-2013 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_sbprofile.h" 85 #include "pub_core_signals.h" 86 #include "pub_core_stacks.h" 87 #include "pub_core_stacktrace.h" // For VG_(get_and_pp_StackTrace)() 88 #include "pub_core_syscall.h" 89 #include "pub_core_syswrap.h" 90 #include "pub_core_tooliface.h" 91 #include "pub_core_translate.h" // For VG_(translate)() 92 #include "pub_core_transtab.h" 93 #include "pub_core_debuginfo.h" // VG_(di_notify_pdb_debuginfo) 94 #include "priv_sched-lock.h" 95 #include "pub_core_scheduler.h" // self 96 #include "pub_core_redir.h" 97 #include "libvex_emnote.h" // VexEmNote 98 99 100 /* --------------------------------------------------------------------- 101 Types and globals for the scheduler. 102 ------------------------------------------------------------------ */ 103 104 /* ThreadId and ThreadState are defined elsewhere*/ 105 106 /* Defines the thread-scheduling timeslice, in terms of the number of 107 basic blocks we attempt to run each thread for. Smaller values 108 give finer interleaving but much increased scheduling overheads. */ 109 #define SCHEDULING_QUANTUM 100000 110 111 /* If False, a fault is Valgrind-internal (ie, a bug) */ 112 Bool VG_(in_generated_code) = False; 113 114 /* 64-bit counter for the number of basic blocks done. */ 115 static ULong bbs_done = 0; 116 117 /* Counter to see if vgdb activity is to be verified. 118 When nr of bbs done reaches vgdb_next_poll, scheduler will 119 poll for gdbserver activity. VG_(force_vgdb_poll) and 120 VG_(disable_vgdb_poll) allows the valgrind core (e.g. m_gdbserver) 121 to control when the next poll will be done. */ 122 static ULong vgdb_next_poll; 123 124 /* Forwards */ 125 static void do_client_request ( ThreadId tid ); 126 static void scheduler_sanity ( ThreadId tid ); 127 static void mostly_clear_thread_record ( ThreadId tid ); 128 129 /* Stats. */ 130 static ULong n_scheduling_events_MINOR = 0; 131 static ULong n_scheduling_events_MAJOR = 0; 132 133 /* Stats: number of XIndirs, and number that missed in the fast 134 cache. */ 135 static ULong stats__n_xindirs = 0; 136 static ULong stats__n_xindir_misses = 0; 137 138 /* And 32-bit temp bins for the above, so that 32-bit platforms don't 139 have to do 64 bit incs on the hot path through 140 VG_(cp_disp_xindir). */ 141 /*global*/ UInt VG_(stats__n_xindirs_32) = 0; 142 /*global*/ UInt VG_(stats__n_xindir_misses_32) = 0; 143 144 /* Sanity checking counts. */ 145 static UInt sanity_fast_count = 0; 146 static UInt sanity_slow_count = 0; 147 148 void VG_(print_scheduler_stats)(void) 149 { 150 VG_(message)(Vg_DebugMsg, 151 "scheduler: %'llu event checks.\n", bbs_done ); 152 VG_(message)(Vg_DebugMsg, 153 "scheduler: %'llu indir transfers, %'llu misses (1 in %llu)\n", 154 stats__n_xindirs, stats__n_xindir_misses, 155 stats__n_xindirs / (stats__n_xindir_misses 156 ? stats__n_xindir_misses : 1)); 157 VG_(message)(Vg_DebugMsg, 158 "scheduler: %'llu/%'llu major/minor sched events.\n", 159 n_scheduling_events_MAJOR, n_scheduling_events_MINOR); 160 VG_(message)(Vg_DebugMsg, 161 " sanity: %d cheap, %d expensive checks.\n", 162 sanity_fast_count, sanity_slow_count ); 163 } 164 165 /* 166 * Mutual exclusion object used to serialize threads. 167 */ 168 static struct sched_lock *the_BigLock; 169 170 171 /* --------------------------------------------------------------------- 172 Helper functions for the scheduler. 173 ------------------------------------------------------------------ */ 174 175 static 176 void print_sched_event ( ThreadId tid, const HChar* what ) 177 { 178 VG_(message)(Vg_DebugMsg, " SCHED[%d]: %s\n", tid, what ); 179 } 180 181 /* For showing SB profiles, if the user asks to see them. */ 182 static 183 void maybe_show_sb_profile ( void ) 184 { 185 /* DO NOT MAKE NON-STATIC */ 186 static ULong bbs_done_lastcheck = 0; 187 /* */ 188 vg_assert(VG_(clo_profyle_interval) > 0); 189 Long delta = (Long)(bbs_done - bbs_done_lastcheck); 190 vg_assert(delta >= 0); 191 if ((ULong)delta >= VG_(clo_profyle_interval)) { 192 bbs_done_lastcheck = bbs_done; 193 VG_(get_and_show_SB_profile)(bbs_done); 194 } 195 } 196 197 static 198 const HChar* name_of_sched_event ( UInt event ) 199 { 200 switch (event) { 201 case VEX_TRC_JMP_INVALICACHE: return "INVALICACHE"; 202 case VEX_TRC_JMP_FLUSHDCACHE: return "FLUSHDCACHE"; 203 case VEX_TRC_JMP_NOREDIR: return "NOREDIR"; 204 case VEX_TRC_JMP_SIGILL: return "SIGILL"; 205 case VEX_TRC_JMP_SIGTRAP: return "SIGTRAP"; 206 case VEX_TRC_JMP_SIGSEGV: return "SIGSEGV"; 207 case VEX_TRC_JMP_SIGBUS: return "SIGBUS"; 208 case VEX_TRC_JMP_SIGFPE_INTOVF: 209 case VEX_TRC_JMP_SIGFPE_INTDIV: return "SIGFPE"; 210 case VEX_TRC_JMP_EMWARN: return "EMWARN"; 211 case VEX_TRC_JMP_EMFAIL: return "EMFAIL"; 212 case VEX_TRC_JMP_CLIENTREQ: return "CLIENTREQ"; 213 case VEX_TRC_JMP_YIELD: return "YIELD"; 214 case VEX_TRC_JMP_NODECODE: return "NODECODE"; 215 case VEX_TRC_JMP_MAPFAIL: return "MAPFAIL"; 216 case VEX_TRC_JMP_SYS_SYSCALL: return "SYSCALL"; 217 case VEX_TRC_JMP_SYS_INT32: return "INT32"; 218 case VEX_TRC_JMP_SYS_INT128: return "INT128"; 219 case VEX_TRC_JMP_SYS_INT129: return "INT129"; 220 case VEX_TRC_JMP_SYS_INT130: return "INT130"; 221 case VEX_TRC_JMP_SYS_SYSENTER: return "SYSENTER"; 222 case VEX_TRC_JMP_BORING: return "VEX_BORING"; 223 224 case VG_TRC_BORING: return "VG_BORING"; 225 case VG_TRC_INNER_FASTMISS: return "FASTMISS"; 226 case VG_TRC_INNER_COUNTERZERO: return "COUNTERZERO"; 227 case VG_TRC_FAULT_SIGNAL: return "FAULTSIGNAL"; 228 case VG_TRC_INVARIANT_FAILED: return "INVFAILED"; 229 case VG_TRC_CHAIN_ME_TO_SLOW_EP: return "CHAIN_ME_SLOW"; 230 case VG_TRC_CHAIN_ME_TO_FAST_EP: return "CHAIN_ME_FAST"; 231 default: return "??UNKNOWN??"; 232 } 233 } 234 235 /* Allocate a completely empty ThreadState record. */ 236 ThreadId VG_(alloc_ThreadState) ( void ) 237 { 238 Int i; 239 for (i = 1; i < VG_N_THREADS; i++) { 240 if (VG_(threads)[i].status == VgTs_Empty) { 241 VG_(threads)[i].status = VgTs_Init; 242 VG_(threads)[i].exitreason = VgSrc_None; 243 if (VG_(threads)[i].thread_name) 244 VG_(arena_free)(VG_AR_CORE, VG_(threads)[i].thread_name); 245 VG_(threads)[i].thread_name = NULL; 246 return i; 247 } 248 } 249 VG_(printf)("vg_alloc_ThreadState: no free slots available\n"); 250 VG_(printf)("Increase VG_N_THREADS, rebuild and try again.\n"); 251 VG_(core_panic)("VG_N_THREADS is too low"); 252 /*NOTREACHED*/ 253 } 254 255 /* 256 Mark a thread as Runnable. This will block until the_BigLock is 257 available, so that we get exclusive access to all the shared 258 structures and the CPU. Up until we get the_BigLock, we must not 259 touch any shared state. 260 261 When this returns, we'll actually be running. 262 */ 263 void VG_(acquire_BigLock)(ThreadId tid, const HChar* who) 264 { 265 ThreadState *tst; 266 267 #if 0 268 if (VG_(clo_trace_sched)) { 269 HChar buf[100]; 270 vg_assert(VG_(strlen)(who) <= 100-50); 271 VG_(sprintf)(buf, "waiting for lock (%s)", who); 272 print_sched_event(tid, buf); 273 } 274 #endif 275 276 /* First, acquire the_BigLock. We can't do anything else safely 277 prior to this point. Even doing debug printing prior to this 278 point is, technically, wrong. */ 279 VG_(acquire_BigLock_LL)(NULL); 280 281 tst = VG_(get_ThreadState)(tid); 282 283 vg_assert(tst->status != VgTs_Runnable); 284 285 tst->status = VgTs_Runnable; 286 287 if (VG_(running_tid) != VG_INVALID_THREADID) 288 VG_(printf)("tid %d found %d running\n", tid, VG_(running_tid)); 289 vg_assert(VG_(running_tid) == VG_INVALID_THREADID); 290 VG_(running_tid) = tid; 291 292 { Addr gsp = VG_(get_SP)(tid); 293 if (NULL != VG_(tdict).track_new_mem_stack_w_ECU) 294 VG_(unknown_SP_update_w_ECU)(gsp, gsp, 0/*unknown origin*/); 295 else 296 VG_(unknown_SP_update)(gsp, gsp); 297 } 298 299 if (VG_(clo_trace_sched)) { 300 HChar buf[150]; 301 vg_assert(VG_(strlen)(who) <= 150-50); 302 VG_(sprintf)(buf, " acquired lock (%s)", who); 303 print_sched_event(tid, buf); 304 } 305 } 306 307 /* 308 Set a thread into a sleeping state, and give up exclusive access to 309 the CPU. On return, the thread must be prepared to block until it 310 is ready to run again (generally this means blocking in a syscall, 311 but it may mean that we remain in a Runnable state and we're just 312 yielding the CPU to another thread). 313 */ 314 void VG_(release_BigLock)(ThreadId tid, ThreadStatus sleepstate, 315 const HChar* who) 316 { 317 ThreadState *tst = VG_(get_ThreadState)(tid); 318 319 vg_assert(tst->status == VgTs_Runnable); 320 321 vg_assert(sleepstate == VgTs_WaitSys || 322 sleepstate == VgTs_Yielding); 323 324 tst->status = sleepstate; 325 326 vg_assert(VG_(running_tid) == tid); 327 VG_(running_tid) = VG_INVALID_THREADID; 328 329 if (VG_(clo_trace_sched)) { 330 HChar buf[200]; 331 vg_assert(VG_(strlen)(who) <= 200-100); 332 VG_(sprintf)(buf, "releasing lock (%s) -> %s", 333 who, VG_(name_of_ThreadStatus)(sleepstate)); 334 print_sched_event(tid, buf); 335 } 336 337 /* Release the_BigLock; this will reschedule any runnable 338 thread. */ 339 VG_(release_BigLock_LL)(NULL); 340 } 341 342 static void init_BigLock(void) 343 { 344 vg_assert(!the_BigLock); 345 the_BigLock = ML_(create_sched_lock)(); 346 } 347 348 static void deinit_BigLock(void) 349 { 350 ML_(destroy_sched_lock)(the_BigLock); 351 the_BigLock = NULL; 352 } 353 354 /* See pub_core_scheduler.h for description */ 355 void VG_(acquire_BigLock_LL) ( const HChar* who ) 356 { 357 ML_(acquire_sched_lock)(the_BigLock); 358 } 359 360 /* See pub_core_scheduler.h for description */ 361 void VG_(release_BigLock_LL) ( const HChar* who ) 362 { 363 ML_(release_sched_lock)(the_BigLock); 364 } 365 366 Bool VG_(owns_BigLock_LL) ( ThreadId tid ) 367 { 368 return (ML_(get_sched_lock_owner)(the_BigLock) 369 == VG_(threads)[tid].os_state.lwpid); 370 } 371 372 373 /* Clear out the ThreadState and release the semaphore. Leaves the 374 ThreadState in VgTs_Zombie state, so that it doesn't get 375 reallocated until the caller is really ready. */ 376 void VG_(exit_thread)(ThreadId tid) 377 { 378 vg_assert(VG_(is_valid_tid)(tid)); 379 vg_assert(VG_(is_running_thread)(tid)); 380 vg_assert(VG_(is_exiting)(tid)); 381 382 mostly_clear_thread_record(tid); 383 VG_(running_tid) = VG_INVALID_THREADID; 384 385 /* There should still be a valid exitreason for this thread */ 386 vg_assert(VG_(threads)[tid].exitreason != VgSrc_None); 387 388 if (VG_(clo_trace_sched)) 389 print_sched_event(tid, "release lock in VG_(exit_thread)"); 390 391 VG_(release_BigLock_LL)(NULL); 392 } 393 394 /* If 'tid' is blocked in a syscall, send it SIGVGKILL so as to get it 395 out of the syscall and onto doing the next thing, whatever that is. 396 If it isn't blocked in a syscall, has no effect on the thread. */ 397 void VG_(get_thread_out_of_syscall)(ThreadId tid) 398 { 399 vg_assert(VG_(is_valid_tid)(tid)); 400 vg_assert(!VG_(is_running_thread)(tid)); 401 402 if (VG_(threads)[tid].status == VgTs_WaitSys) { 403 if (VG_(clo_trace_signals)) { 404 VG_(message)(Vg_DebugMsg, 405 "get_thread_out_of_syscall zaps tid %d lwp %d\n", 406 tid, VG_(threads)[tid].os_state.lwpid); 407 } 408 # if defined(VGO_darwin) 409 { 410 // GrP fixme use mach primitives on darwin? 411 // GrP fixme thread_abort_safely? 412 // GrP fixme race for thread with WaitSys set but not in syscall yet? 413 extern kern_return_t thread_abort(mach_port_t); 414 thread_abort(VG_(threads)[tid].os_state.lwpid); 415 } 416 # else 417 { 418 __attribute__((unused)) 419 Int r = VG_(tkill)(VG_(threads)[tid].os_state.lwpid, VG_SIGVGKILL); 420 /* JRS 2009-Mar-20: should we assert for r==0 (tkill succeeded)? 421 I'm really not sure. Here's a race scenario which argues 422 that we shoudn't; but equally I'm not sure the scenario is 423 even possible, because of constraints caused by the question 424 of who holds the BigLock when. 425 426 Target thread tid does sys_read on a socket and blocks. This 427 function gets called, and we observe correctly that tid's 428 status is WaitSys but then for whatever reason this function 429 goes very slowly for a while. Then data arrives from 430 wherever, tid's sys_read returns, tid exits. Then we do 431 tkill on tid, but tid no longer exists; tkill returns an 432 error code and the assert fails. */ 433 /* vg_assert(r == 0); */ 434 } 435 # endif 436 } 437 } 438 439 /* 440 Yield the CPU for a short time to let some other thread run. 441 */ 442 void VG_(vg_yield)(void) 443 { 444 ThreadId tid = VG_(running_tid); 445 446 vg_assert(tid != VG_INVALID_THREADID); 447 vg_assert(VG_(threads)[tid].os_state.lwpid == VG_(gettid)()); 448 449 VG_(release_BigLock)(tid, VgTs_Yielding, "VG_(vg_yield)"); 450 451 /* 452 Tell the kernel we're yielding. 453 */ 454 VG_(do_syscall0)(__NR_sched_yield); 455 456 VG_(acquire_BigLock)(tid, "VG_(vg_yield)"); 457 } 458 459 460 /* Set the standard set of blocked signals, used whenever we're not 461 running a client syscall. */ 462 static void block_signals(void) 463 { 464 vki_sigset_t mask; 465 466 VG_(sigfillset)(&mask); 467 468 /* Don't block these because they're synchronous */ 469 VG_(sigdelset)(&mask, VKI_SIGSEGV); 470 VG_(sigdelset)(&mask, VKI_SIGBUS); 471 VG_(sigdelset)(&mask, VKI_SIGFPE); 472 VG_(sigdelset)(&mask, VKI_SIGILL); 473 VG_(sigdelset)(&mask, VKI_SIGTRAP); 474 475 /* Can't block these anyway */ 476 VG_(sigdelset)(&mask, VKI_SIGSTOP); 477 VG_(sigdelset)(&mask, VKI_SIGKILL); 478 479 VG_(sigprocmask)(VKI_SIG_SETMASK, &mask, NULL); 480 } 481 482 static void os_state_clear(ThreadState *tst) 483 { 484 tst->os_state.lwpid = 0; 485 tst->os_state.threadgroup = 0; 486 # if defined(VGO_linux) 487 /* no other fields to clear */ 488 # elif defined(VGO_darwin) 489 tst->os_state.post_mach_trap_fn = NULL; 490 tst->os_state.pthread = 0; 491 tst->os_state.func_arg = 0; 492 VG_(memset)(&tst->os_state.child_go, 0, sizeof(tst->os_state.child_go)); 493 VG_(memset)(&tst->os_state.child_done, 0, sizeof(tst->os_state.child_done)); 494 tst->os_state.wq_jmpbuf_valid = False; 495 tst->os_state.remote_port = 0; 496 tst->os_state.msgh_id = 0; 497 VG_(memset)(&tst->os_state.mach_args, 0, sizeof(tst->os_state.mach_args)); 498 # else 499 # error "Unknown OS" 500 # endif 501 } 502 503 static void os_state_init(ThreadState *tst) 504 { 505 tst->os_state.valgrind_stack_base = 0; 506 tst->os_state.valgrind_stack_init_SP = 0; 507 os_state_clear(tst); 508 } 509 510 static 511 void mostly_clear_thread_record ( ThreadId tid ) 512 { 513 vki_sigset_t savedmask; 514 515 vg_assert(tid >= 0 && tid < VG_N_THREADS); 516 VG_(cleanup_thread)(&VG_(threads)[tid].arch); 517 VG_(threads)[tid].tid = tid; 518 519 /* Leave the thread in Zombie, so that it doesn't get reallocated 520 until the caller is finally done with the thread stack. */ 521 VG_(threads)[tid].status = VgTs_Zombie; 522 523 VG_(sigemptyset)(&VG_(threads)[tid].sig_mask); 524 VG_(sigemptyset)(&VG_(threads)[tid].tmp_sig_mask); 525 526 os_state_clear(&VG_(threads)[tid]); 527 528 /* start with no altstack */ 529 VG_(threads)[tid].altstack.ss_sp = (void *)0xdeadbeef; 530 VG_(threads)[tid].altstack.ss_size = 0; 531 VG_(threads)[tid].altstack.ss_flags = VKI_SS_DISABLE; 532 533 VG_(clear_out_queued_signals)(tid, &savedmask); 534 535 VG_(threads)[tid].sched_jmpbuf_valid = False; 536 } 537 538 /* 539 Called in the child after fork. If the parent has multiple 540 threads, then we've inherited a VG_(threads) array describing them, 541 but only the thread which called fork() is actually alive in the 542 child. This functions needs to clean up all those other thread 543 structures. 544 545 Whichever tid in the parent which called fork() becomes the 546 master_tid in the child. That's because the only living slot in 547 VG_(threads) in the child after fork is VG_(threads)[tid], and it 548 would be too hard to try to re-number the thread and relocate the 549 thread state down to VG_(threads)[1]. 550 551 This function also needs to reinitialize the_BigLock, since 552 otherwise we may end up sharing its state with the parent, which 553 would be deeply confusing. 554 */ 555 static void sched_fork_cleanup(ThreadId me) 556 { 557 ThreadId tid; 558 vg_assert(VG_(running_tid) == me); 559 560 # if defined(VGO_darwin) 561 // GrP fixme hack reset Mach ports 562 VG_(mach_init)(); 563 # endif 564 565 VG_(threads)[me].os_state.lwpid = VG_(gettid)(); 566 VG_(threads)[me].os_state.threadgroup = VG_(getpid)(); 567 568 /* clear out all the unused thread slots */ 569 for (tid = 1; tid < VG_N_THREADS; tid++) { 570 if (tid != me) { 571 mostly_clear_thread_record(tid); 572 VG_(threads)[tid].status = VgTs_Empty; 573 VG_(clear_syscallInfo)(tid); 574 } 575 } 576 577 /* re-init and take the sema */ 578 deinit_BigLock(); 579 init_BigLock(); 580 VG_(acquire_BigLock_LL)(NULL); 581 } 582 583 584 /* First phase of initialisation of the scheduler. Initialise the 585 bigLock, zeroise the VG_(threads) structure and decide on the 586 ThreadId of the root thread. 587 */ 588 ThreadId VG_(scheduler_init_phase1) ( void ) 589 { 590 Int i; 591 ThreadId tid_main; 592 593 VG_(debugLog)(1,"sched","sched_init_phase1\n"); 594 595 if (VG_(clo_fair_sched) != disable_fair_sched 596 && !ML_(set_sched_lock_impl)(sched_lock_ticket) 597 && VG_(clo_fair_sched) == enable_fair_sched) 598 { 599 VG_(printf)("Error: fair scheduling is not supported on this system.\n"); 600 VG_(exit)(1); 601 } 602 603 if (VG_(clo_verbosity) > 1) { 604 VG_(message)(Vg_DebugMsg, 605 "Scheduler: using %s scheduler lock implementation.\n", 606 ML_(get_sched_lock_name)()); 607 } 608 609 init_BigLock(); 610 611 for (i = 0 /* NB; not 1 */; i < VG_N_THREADS; i++) { 612 /* Paranoia .. completely zero it out. */ 613 VG_(memset)( & VG_(threads)[i], 0, sizeof( VG_(threads)[i] ) ); 614 615 VG_(threads)[i].sig_queue = NULL; 616 617 os_state_init(&VG_(threads)[i]); 618 mostly_clear_thread_record(i); 619 620 VG_(threads)[i].status = VgTs_Empty; 621 VG_(threads)[i].client_stack_szB = 0; 622 VG_(threads)[i].client_stack_highest_word = (Addr)NULL; 623 VG_(threads)[i].err_disablement_level = 0; 624 VG_(threads)[i].thread_name = NULL; 625 } 626 627 tid_main = VG_(alloc_ThreadState)(); 628 629 /* Bleh. Unfortunately there are various places in the system that 630 assume that the main thread has a ThreadId of 1. 631 - Helgrind (possibly) 632 - stack overflow message in default_action() in m_signals.c 633 - definitely a lot more places 634 */ 635 vg_assert(tid_main == 1); 636 637 return tid_main; 638 } 639 640 641 /* Second phase of initialisation of the scheduler. Given the root 642 ThreadId computed by first phase of initialisation, fill in stack 643 details and acquire bigLock. Initialise the scheduler. This is 644 called at startup. The caller subsequently initialises the guest 645 state components of this main thread. 646 */ 647 void VG_(scheduler_init_phase2) ( ThreadId tid_main, 648 Addr clstack_end, 649 SizeT clstack_size ) 650 { 651 VG_(debugLog)(1,"sched","sched_init_phase2: tid_main=%d, " 652 "cls_end=0x%lx, cls_sz=%ld\n", 653 tid_main, clstack_end, clstack_size); 654 655 vg_assert(VG_IS_PAGE_ALIGNED(clstack_end+1)); 656 vg_assert(VG_IS_PAGE_ALIGNED(clstack_size)); 657 658 VG_(threads)[tid_main].client_stack_highest_word 659 = clstack_end + 1 - sizeof(UWord); 660 VG_(threads)[tid_main].client_stack_szB 661 = clstack_size; 662 663 VG_(atfork)(NULL, NULL, sched_fork_cleanup); 664 } 665 666 667 /* --------------------------------------------------------------------- 668 Helpers for running translations. 669 ------------------------------------------------------------------ */ 670 671 /* Use gcc's built-in setjmp/longjmp. longjmp must not restore signal 672 mask state, but does need to pass "val" through. jumped must be a 673 volatile UWord. */ 674 #define SCHEDSETJMP(tid, jumped, stmt) \ 675 do { \ 676 ThreadState * volatile _qq_tst = VG_(get_ThreadState)(tid); \ 677 \ 678 (jumped) = VG_MINIMAL_SETJMP(_qq_tst->sched_jmpbuf); \ 679 if ((jumped) == ((UWord)0)) { \ 680 vg_assert(!_qq_tst->sched_jmpbuf_valid); \ 681 _qq_tst->sched_jmpbuf_valid = True; \ 682 stmt; \ 683 } else if (VG_(clo_trace_sched)) \ 684 VG_(printf)("SCHEDSETJMP(line %d) tid %d, jumped=%ld\n", \ 685 __LINE__, tid, jumped); \ 686 vg_assert(_qq_tst->sched_jmpbuf_valid); \ 687 _qq_tst->sched_jmpbuf_valid = False; \ 688 } while(0) 689 690 691 /* Do various guest state alignment checks prior to running a thread. 692 Specifically, check that what we have matches Vex's guest state 693 layout requirements. See libvex.h for details, but in short the 694 requirements are: There must be no holes in between the primary 695 guest state, its two copies, and the spill area. In short, all 4 696 areas must have a 16-aligned size and be 16-aligned, and placed 697 back-to-back. */ 698 static void do_pre_run_checks ( ThreadState* tst ) 699 { 700 Addr a_vex = (Addr) & tst->arch.vex; 701 Addr a_vexsh1 = (Addr) & tst->arch.vex_shadow1; 702 Addr a_vexsh2 = (Addr) & tst->arch.vex_shadow2; 703 Addr a_spill = (Addr) & tst->arch.vex_spill; 704 UInt sz_vex = (UInt) sizeof tst->arch.vex; 705 UInt sz_vexsh1 = (UInt) sizeof tst->arch.vex_shadow1; 706 UInt sz_vexsh2 = (UInt) sizeof tst->arch.vex_shadow2; 707 UInt sz_spill = (UInt) sizeof tst->arch.vex_spill; 708 709 if (0) 710 VG_(printf)("gst %p %d, sh1 %p %d, " 711 "sh2 %p %d, spill %p %d\n", 712 (void*)a_vex, sz_vex, 713 (void*)a_vexsh1, sz_vexsh1, 714 (void*)a_vexsh2, sz_vexsh2, 715 (void*)a_spill, sz_spill ); 716 717 vg_assert(VG_IS_16_ALIGNED(sz_vex)); 718 vg_assert(VG_IS_16_ALIGNED(sz_vexsh1)); 719 vg_assert(VG_IS_16_ALIGNED(sz_vexsh2)); 720 vg_assert(VG_IS_16_ALIGNED(sz_spill)); 721 722 vg_assert(VG_IS_16_ALIGNED(a_vex)); 723 vg_assert(VG_IS_16_ALIGNED(a_vexsh1)); 724 vg_assert(VG_IS_16_ALIGNED(a_vexsh2)); 725 vg_assert(VG_IS_16_ALIGNED(a_spill)); 726 727 /* Check that the guest state and its two shadows have the same 728 size, and that there are no holes in between. The latter is 729 important because Memcheck assumes that it can reliably access 730 the shadows by indexing off a pointer to the start of the 731 primary guest state area. */ 732 vg_assert(sz_vex == sz_vexsh1); 733 vg_assert(sz_vex == sz_vexsh2); 734 vg_assert(a_vex + 1 * sz_vex == a_vexsh1); 735 vg_assert(a_vex + 2 * sz_vex == a_vexsh2); 736 /* Also check there's no hole between the second shadow area and 737 the spill area. */ 738 vg_assert(sz_spill == LibVEX_N_SPILL_BYTES); 739 vg_assert(a_vex + 3 * sz_vex == a_spill); 740 741 # if defined(VGA_x86) 742 /* x86 XMM regs must form an array, ie, have no holes in 743 between. */ 744 vg_assert( 745 (offsetof(VexGuestX86State,guest_XMM7) 746 - offsetof(VexGuestX86State,guest_XMM0)) 747 == (8/*#regs*/-1) * 16/*bytes per reg*/ 748 ); 749 vg_assert(VG_IS_16_ALIGNED(offsetof(VexGuestX86State,guest_XMM0))); 750 vg_assert(VG_IS_8_ALIGNED(offsetof(VexGuestX86State,guest_FPREG))); 751 vg_assert(8 == offsetof(VexGuestX86State,guest_EAX)); 752 vg_assert(VG_IS_4_ALIGNED(offsetof(VexGuestX86State,guest_EAX))); 753 vg_assert(VG_IS_4_ALIGNED(offsetof(VexGuestX86State,guest_EIP))); 754 # endif 755 756 # if defined(VGA_amd64) 757 /* amd64 YMM regs must form an array, ie, have no holes in 758 between. */ 759 vg_assert( 760 (offsetof(VexGuestAMD64State,guest_YMM16) 761 - offsetof(VexGuestAMD64State,guest_YMM0)) 762 == (17/*#regs*/-1) * 32/*bytes per reg*/ 763 ); 764 vg_assert(VG_IS_16_ALIGNED(offsetof(VexGuestAMD64State,guest_YMM0))); 765 vg_assert(VG_IS_8_ALIGNED(offsetof(VexGuestAMD64State,guest_FPREG))); 766 vg_assert(16 == offsetof(VexGuestAMD64State,guest_RAX)); 767 vg_assert(VG_IS_8_ALIGNED(offsetof(VexGuestAMD64State,guest_RAX))); 768 vg_assert(VG_IS_8_ALIGNED(offsetof(VexGuestAMD64State,guest_RIP))); 769 # endif 770 771 # if defined(VGA_ppc32) || defined(VGA_ppc64) 772 /* ppc guest_state vector regs must be 16 byte aligned for 773 loads/stores. This is important! */ 774 vg_assert(VG_IS_16_ALIGNED(& tst->arch.vex.guest_VSR0)); 775 vg_assert(VG_IS_16_ALIGNED(& tst->arch.vex_shadow1.guest_VSR0)); 776 vg_assert(VG_IS_16_ALIGNED(& tst->arch.vex_shadow2.guest_VSR0)); 777 /* be extra paranoid .. */ 778 vg_assert(VG_IS_16_ALIGNED(& tst->arch.vex.guest_VSR1)); 779 vg_assert(VG_IS_16_ALIGNED(& tst->arch.vex_shadow1.guest_VSR1)); 780 vg_assert(VG_IS_16_ALIGNED(& tst->arch.vex_shadow2.guest_VSR1)); 781 # endif 782 783 # if defined(VGA_arm) 784 /* arm guest_state VFP regs must be 8 byte aligned for 785 loads/stores. Let's use 16 just to be on the safe side. */ 786 vg_assert(VG_IS_16_ALIGNED(& tst->arch.vex.guest_D0)); 787 vg_assert(VG_IS_16_ALIGNED(& tst->arch.vex_shadow1.guest_D0)); 788 vg_assert(VG_IS_16_ALIGNED(& tst->arch.vex_shadow2.guest_D0)); 789 /* be extra paranoid .. */ 790 vg_assert(VG_IS_8_ALIGNED(& tst->arch.vex.guest_D1)); 791 vg_assert(VG_IS_8_ALIGNED(& tst->arch.vex_shadow1.guest_D1)); 792 vg_assert(VG_IS_8_ALIGNED(& tst->arch.vex_shadow2.guest_D1)); 793 # endif 794 795 # if defined(VGA_arm64) 796 vg_assert(VG_IS_8_ALIGNED(& tst->arch.vex.guest_X0)); 797 vg_assert(VG_IS_8_ALIGNED(& tst->arch.vex_shadow1.guest_X0)); 798 vg_assert(VG_IS_8_ALIGNED(& tst->arch.vex_shadow2.guest_X0)); 799 vg_assert(VG_IS_16_ALIGNED(& tst->arch.vex.guest_Q0)); 800 vg_assert(VG_IS_16_ALIGNED(& tst->arch.vex_shadow1.guest_Q0)); 801 vg_assert(VG_IS_16_ALIGNED(& tst->arch.vex_shadow2.guest_Q0)); 802 # endif 803 804 # if defined(VGA_s390x) 805 /* no special requirements */ 806 # endif 807 808 # if defined(VGA_mips32) || defined(VGA_mips64) 809 /* no special requirements */ 810 # endif 811 } 812 813 // NO_VGDB_POLL value ensures vgdb is not polled, while 814 // VGDB_POLL_ASAP ensures that the next scheduler call 815 // will cause a poll. 816 #define NO_VGDB_POLL 0xffffffffffffffffULL 817 #define VGDB_POLL_ASAP 0x0ULL 818 819 void VG_(disable_vgdb_poll) (void ) 820 { 821 vgdb_next_poll = NO_VGDB_POLL; 822 } 823 void VG_(force_vgdb_poll) ( void ) 824 { 825 vgdb_next_poll = VGDB_POLL_ASAP; 826 } 827 828 /* Run the thread tid for a while, and return a VG_TRC_* value 829 indicating why VG_(disp_run_translations) stopped, and possibly an 830 auxiliary word. Also, only allow the thread to run for at most 831 *dispatchCtrP events. If (as is the normal case) use_alt_host_addr 832 is False, we are running ordinary redir'd translations, and we 833 should therefore start by looking up the guest next IP in TT. If 834 it is True then we ignore the guest next IP and just run from 835 alt_host_addr, which presumably points at host code for a no-redir 836 translation. 837 838 Return results are placed in two_words. two_words[0] is set to the 839 TRC. In the case where that is VG_TRC_CHAIN_ME_TO_{SLOW,FAST}_EP, 840 the address to patch is placed in two_words[1]. 841 */ 842 static 843 void run_thread_for_a_while ( /*OUT*/HWord* two_words, 844 /*MOD*/Int* dispatchCtrP, 845 ThreadId tid, 846 HWord alt_host_addr, 847 Bool use_alt_host_addr ) 848 { 849 volatile HWord jumped = 0; 850 volatile ThreadState* tst = NULL; /* stop gcc complaining */ 851 volatile Int done_this_time = 0; 852 volatile HWord host_code_addr = 0; 853 854 /* Paranoia */ 855 vg_assert(VG_(is_valid_tid)(tid)); 856 vg_assert(VG_(is_running_thread)(tid)); 857 vg_assert(!VG_(is_exiting)(tid)); 858 vg_assert(*dispatchCtrP > 0); 859 860 tst = VG_(get_ThreadState)(tid); 861 do_pre_run_checks( (ThreadState*)tst ); 862 /* end Paranoia */ 863 864 /* Futz with the XIndir stats counters. */ 865 vg_assert(VG_(stats__n_xindirs_32) == 0); 866 vg_assert(VG_(stats__n_xindir_misses_32) == 0); 867 868 /* Clear return area. */ 869 two_words[0] = two_words[1] = 0; 870 871 /* Figure out where we're starting from. */ 872 if (use_alt_host_addr) { 873 /* unusual case -- no-redir translation */ 874 host_code_addr = alt_host_addr; 875 } else { 876 /* normal case -- redir translation */ 877 UInt cno = (UInt)VG_TT_FAST_HASH((Addr)tst->arch.vex.VG_INSTR_PTR); 878 if (LIKELY(VG_(tt_fast)[cno].guest == (Addr)tst->arch.vex.VG_INSTR_PTR)) 879 host_code_addr = VG_(tt_fast)[cno].host; 880 else { 881 AddrH res = 0; 882 /* not found in VG_(tt_fast). Searching here the transtab 883 improves the performance compared to returning directly 884 to the scheduler. */ 885 Bool found = VG_(search_transtab)(&res, NULL, NULL, 886 (Addr)tst->arch.vex.VG_INSTR_PTR, 887 True/*upd cache*/ 888 ); 889 if (LIKELY(found)) { 890 host_code_addr = res; 891 } else { 892 /* At this point, we know that we intended to start at a 893 normal redir translation, but it was not found. In 894 which case we can return now claiming it's not 895 findable. */ 896 two_words[0] = VG_TRC_INNER_FASTMISS; /* hmm, is that right? */ 897 return; 898 } 899 } 900 } 901 /* We have either a no-redir or a redir translation. */ 902 vg_assert(host_code_addr != 0); /* implausible */ 903 904 /* there should be no undealt-with signals */ 905 //vg_assert(VG_(threads)[tid].siginfo.si_signo == 0); 906 907 /* Set up event counter stuff for the run. */ 908 tst->arch.vex.host_EvC_COUNTER = *dispatchCtrP; 909 tst->arch.vex.host_EvC_FAILADDR 910 = (HWord)VG_(fnptr_to_fnentry)( &VG_(disp_cp_evcheck_fail) ); 911 912 if (0) { 913 vki_sigset_t m; 914 Int i, err = VG_(sigprocmask)(VKI_SIG_SETMASK, NULL, &m); 915 vg_assert(err == 0); 916 VG_(printf)("tid %d: entering code with unblocked signals: ", tid); 917 for (i = 1; i <= _VKI_NSIG; i++) 918 if (!VG_(sigismember)(&m, i)) 919 VG_(printf)("%d ", i); 920 VG_(printf)("\n"); 921 } 922 923 /* Set up return-value area. */ 924 925 // Tell the tool this thread is about to run client code 926 VG_TRACK( start_client_code, tid, bbs_done ); 927 928 vg_assert(VG_(in_generated_code) == False); 929 VG_(in_generated_code) = True; 930 931 SCHEDSETJMP( 932 tid, 933 jumped, 934 VG_(disp_run_translations)( 935 two_words, 936 (void*)&tst->arch.vex, 937 host_code_addr 938 ) 939 ); 940 941 vg_assert(VG_(in_generated_code) == True); 942 VG_(in_generated_code) = False; 943 944 if (jumped != (HWord)0) { 945 /* We get here if the client took a fault that caused our signal 946 handler to longjmp. */ 947 vg_assert(two_words[0] == 0 && two_words[1] == 0); // correct? 948 two_words[0] = VG_TRC_FAULT_SIGNAL; 949 two_words[1] = 0; 950 block_signals(); 951 } 952 953 /* Merge the 32-bit XIndir/miss counters into the 64 bit versions, 954 and zero out the 32-bit ones in preparation for the next run of 955 generated code. */ 956 stats__n_xindirs += (ULong)VG_(stats__n_xindirs_32); 957 VG_(stats__n_xindirs_32) = 0; 958 stats__n_xindir_misses += (ULong)VG_(stats__n_xindir_misses_32); 959 VG_(stats__n_xindir_misses_32) = 0; 960 961 /* Inspect the event counter. */ 962 vg_assert((Int)tst->arch.vex.host_EvC_COUNTER >= -1); 963 vg_assert(tst->arch.vex.host_EvC_FAILADDR 964 == (HWord)VG_(fnptr_to_fnentry)( &VG_(disp_cp_evcheck_fail)) ); 965 966 done_this_time = *dispatchCtrP - ((Int)tst->arch.vex.host_EvC_COUNTER + 1); 967 968 vg_assert(done_this_time >= 0); 969 bbs_done += (ULong)done_this_time; 970 971 *dispatchCtrP -= done_this_time; 972 vg_assert(*dispatchCtrP >= 0); 973 974 // Tell the tool this thread has stopped running client code 975 VG_TRACK( stop_client_code, tid, bbs_done ); 976 977 if (bbs_done >= vgdb_next_poll) { 978 if (VG_(clo_vgdb_poll)) 979 vgdb_next_poll = bbs_done + (ULong)VG_(clo_vgdb_poll); 980 else 981 /* value was changed due to gdbserver invocation via ptrace */ 982 vgdb_next_poll = NO_VGDB_POLL; 983 if (VG_(gdbserver_activity) (tid)) 984 VG_(gdbserver) (tid); 985 } 986 987 /* TRC value and possible auxiliary patch-address word are already 988 in two_words[0] and [1] respectively, as a result of the call to 989 VG_(run_innerloop). */ 990 /* Stay sane .. */ 991 if (two_words[0] == VG_TRC_CHAIN_ME_TO_SLOW_EP 992 || two_words[0] == VG_TRC_CHAIN_ME_TO_FAST_EP) { 993 vg_assert(two_words[1] != 0); /* we have a legit patch addr */ 994 } else { 995 vg_assert(two_words[1] == 0); /* nobody messed with it */ 996 } 997 } 998 999 1000 /* --------------------------------------------------------------------- 1001 The scheduler proper. 1002 ------------------------------------------------------------------ */ 1003 1004 static void handle_tt_miss ( ThreadId tid ) 1005 { 1006 Bool found; 1007 Addr ip = VG_(get_IP)(tid); 1008 1009 /* Trivial event. Miss in the fast-cache. Do a full 1010 lookup for it. */ 1011 found = VG_(search_transtab)( NULL, NULL, NULL, 1012 ip, True/*upd_fast_cache*/ ); 1013 if (UNLIKELY(!found)) { 1014 /* Not found; we need to request a translation. */ 1015 if (VG_(translate)( tid, ip, /*debug*/False, 0/*not verbose*/, 1016 bbs_done, True/*allow redirection*/ )) { 1017 found = VG_(search_transtab)( NULL, NULL, NULL, 1018 ip, True ); 1019 vg_assert2(found, "handle_tt_miss: missing tt_fast entry"); 1020 1021 } else { 1022 // If VG_(translate)() fails, it's because it had to throw a 1023 // signal because the client jumped to a bad address. That 1024 // means that either a signal has been set up for delivery, 1025 // or the thread has been marked for termination. Either 1026 // way, we just need to go back into the scheduler loop. 1027 } 1028 } 1029 } 1030 1031 static 1032 void handle_chain_me ( ThreadId tid, void* place_to_chain, Bool toFastEP ) 1033 { 1034 Bool found = False; 1035 Addr ip = VG_(get_IP)(tid); 1036 UInt to_sNo = (UInt)-1; 1037 UInt to_tteNo = (UInt)-1; 1038 1039 found = VG_(search_transtab)( NULL, &to_sNo, &to_tteNo, 1040 ip, False/*dont_upd_fast_cache*/ ); 1041 if (!found) { 1042 /* Not found; we need to request a translation. */ 1043 if (VG_(translate)( tid, ip, /*debug*/False, 0/*not verbose*/, 1044 bbs_done, True/*allow redirection*/ )) { 1045 found = VG_(search_transtab)( NULL, &to_sNo, &to_tteNo, 1046 ip, False ); 1047 vg_assert2(found, "handle_chain_me: missing tt_fast entry"); 1048 } else { 1049 // If VG_(translate)() fails, it's because it had to throw a 1050 // signal because the client jumped to a bad address. That 1051 // means that either a signal has been set up for delivery, 1052 // or the thread has been marked for termination. Either 1053 // way, we just need to go back into the scheduler loop. 1054 return; 1055 } 1056 } 1057 vg_assert(found); 1058 vg_assert(to_sNo != -1); 1059 vg_assert(to_tteNo != -1); 1060 1061 /* So, finally we know where to patch through to. Do the patching 1062 and update the various admin tables that allow it to be undone 1063 in the case that the destination block gets deleted. */ 1064 VG_(tt_tc_do_chaining)( place_to_chain, 1065 to_sNo, to_tteNo, toFastEP ); 1066 } 1067 1068 static void handle_syscall(ThreadId tid, UInt trc) 1069 { 1070 ThreadState * volatile tst = VG_(get_ThreadState)(tid); 1071 volatile UWord jumped; 1072 1073 /* Syscall may or may not block; either way, it will be 1074 complete by the time this call returns, and we'll be 1075 runnable again. We could take a signal while the 1076 syscall runs. */ 1077 1078 if (VG_(clo_sanity_level >= 3)) 1079 VG_(am_do_sync_check)("(BEFORE SYSCALL)",__FILE__,__LINE__); 1080 1081 SCHEDSETJMP(tid, jumped, VG_(client_syscall)(tid, trc)); 1082 1083 if (VG_(clo_sanity_level >= 3)) 1084 VG_(am_do_sync_check)("(AFTER SYSCALL)",__FILE__,__LINE__); 1085 1086 if (!VG_(is_running_thread)(tid)) 1087 VG_(printf)("tid %d not running; VG_(running_tid)=%d, tid %d status %d\n", 1088 tid, VG_(running_tid), tid, tst->status); 1089 vg_assert(VG_(is_running_thread)(tid)); 1090 1091 if (jumped != (UWord)0) { 1092 block_signals(); 1093 VG_(poll_signals)(tid); 1094 } 1095 } 1096 1097 /* tid just requested a jump to the noredir version of its current 1098 program counter. So make up that translation if needed, run it, 1099 and return the resulting thread return code in two_words[]. */ 1100 static 1101 void handle_noredir_jump ( /*OUT*/HWord* two_words, 1102 /*MOD*/Int* dispatchCtrP, 1103 ThreadId tid ) 1104 { 1105 /* Clear return area. */ 1106 two_words[0] = two_words[1] = 0; 1107 1108 AddrH hcode = 0; 1109 Addr ip = VG_(get_IP)(tid); 1110 1111 Bool found = VG_(search_unredir_transtab)( &hcode, ip ); 1112 if (!found) { 1113 /* Not found; we need to request a translation. */ 1114 if (VG_(translate)( tid, ip, /*debug*/False, 0/*not verbose*/, bbs_done, 1115 False/*NO REDIRECTION*/ )) { 1116 1117 found = VG_(search_unredir_transtab)( &hcode, ip ); 1118 vg_assert2(found, "unredir translation missing after creation?!"); 1119 } else { 1120 // If VG_(translate)() fails, it's because it had to throw a 1121 // signal because the client jumped to a bad address. That 1122 // means that either a signal has been set up for delivery, 1123 // or the thread has been marked for termination. Either 1124 // way, we just need to go back into the scheduler loop. 1125 two_words[0] = VG_TRC_BORING; 1126 return; 1127 } 1128 1129 } 1130 1131 vg_assert(found); 1132 vg_assert(hcode != 0); 1133 1134 /* Otherwise run it and return the resulting VG_TRC_* value. */ 1135 vg_assert(*dispatchCtrP > 0); /* so as to guarantee progress */ 1136 run_thread_for_a_while( two_words, dispatchCtrP, tid, 1137 hcode, True/*use hcode*/ ); 1138 } 1139 1140 1141 /* 1142 Run a thread until it wants to exit. 1143 1144 We assume that the caller has already called VG_(acquire_BigLock) for 1145 us, so we own the VCPU. Also, all signals are blocked. 1146 */ 1147 VgSchedReturnCode VG_(scheduler) ( ThreadId tid ) 1148 { 1149 /* Holds the remaining size of this thread's "timeslice". */ 1150 Int dispatch_ctr = 0; 1151 1152 ThreadState *tst = VG_(get_ThreadState)(tid); 1153 static Bool vgdb_startup_action_done = False; 1154 1155 if (VG_(clo_trace_sched)) 1156 print_sched_event(tid, "entering VG_(scheduler)"); 1157 1158 /* Do vgdb initialization (but once). Only the first (main) task 1159 starting up will do the below. 1160 Initialize gdbserver earlier than at the first 1161 thread VG_(scheduler) is causing problems: 1162 * at the end of VG_(scheduler_init_phase2) : 1163 The main thread is in VgTs_Init state, but in a not yet 1164 consistent state => the thread cannot be reported to gdb 1165 (e.g. causes an assert in LibVEX_GuestX86_get_eflags when giving 1166 back the guest registers to gdb). 1167 * at end of valgrind_main, just 1168 before VG_(main_thread_wrapper_NORETURN)(1) : 1169 The main thread is still in VgTs_Init state but in a 1170 more advanced state. However, the thread state is not yet 1171 completely initialized : a.o., the os_state is not yet fully 1172 set => the thread is then not properly reported to gdb, 1173 which is then confused (causing e.g. a duplicate thread be 1174 shown, without thread id). 1175 * it would be possible to initialize gdbserver "lower" in the 1176 call stack (e.g. in VG_(main_thread_wrapper_NORETURN)) but 1177 these are platform dependent and the place at which 1178 the thread state is completely initialized is not 1179 specific anymore to the main thread (so a similar "do it only 1180 once" would be needed). 1181 1182 => a "once only" initialization here is the best compromise. */ 1183 if (!vgdb_startup_action_done) { 1184 vg_assert(tid == 1); // it must be the main thread. 1185 vgdb_startup_action_done = True; 1186 if (VG_(clo_vgdb) != Vg_VgdbNo) { 1187 /* If we have to poll, ensures we do an initial poll at first 1188 scheduler call. Otherwise, ensure no poll (unless interrupted 1189 by ptrace). */ 1190 if (VG_(clo_vgdb_poll)) 1191 VG_(force_vgdb_poll) (); 1192 else 1193 VG_(disable_vgdb_poll) (); 1194 1195 vg_assert (VG_(dyn_vgdb_error) == VG_(clo_vgdb_error)); 1196 /* As we are initializing, VG_(dyn_vgdb_error) can't have been 1197 changed yet. */ 1198 1199 VG_(gdbserver_prerun_action) (1); 1200 } else { 1201 VG_(disable_vgdb_poll) (); 1202 } 1203 } 1204 1205 /* set the proper running signal mask */ 1206 block_signals(); 1207 1208 vg_assert(VG_(is_running_thread)(tid)); 1209 1210 dispatch_ctr = SCHEDULING_QUANTUM; 1211 1212 while (!VG_(is_exiting)(tid)) { 1213 1214 vg_assert(dispatch_ctr >= 0); 1215 if (dispatch_ctr == 0) { 1216 1217 /* Our slice is done, so yield the CPU to another thread. On 1218 Linux, this doesn't sleep between sleeping and running, 1219 since that would take too much time. */ 1220 1221 /* 4 July 06: it seems that a zero-length nsleep is needed to 1222 cause async thread cancellation (canceller.c) to terminate 1223 in finite time; else it is in some kind of race/starvation 1224 situation and completion is arbitrarily delayed (although 1225 this is not a deadlock). 1226 1227 Unfortunately these sleeps cause MPI jobs not to terminate 1228 sometimes (some kind of livelock). So sleeping once 1229 every N opportunities appears to work. */ 1230 1231 /* 3 Aug 06: doing sys__nsleep works but crashes some apps. 1232 sys_yield also helps the problem, whilst not crashing apps. */ 1233 1234 VG_(release_BigLock)(tid, VgTs_Yielding, 1235 "VG_(scheduler):timeslice"); 1236 /* ------------ now we don't have The Lock ------------ */ 1237 1238 VG_(acquire_BigLock)(tid, "VG_(scheduler):timeslice"); 1239 /* ------------ now we do have The Lock ------------ */ 1240 1241 /* OK, do some relatively expensive housekeeping stuff */ 1242 scheduler_sanity(tid); 1243 VG_(sanity_check_general)(False); 1244 1245 /* Look for any pending signals for this thread, and set them up 1246 for delivery */ 1247 VG_(poll_signals)(tid); 1248 1249 if (VG_(is_exiting)(tid)) 1250 break; /* poll_signals picked up a fatal signal */ 1251 1252 /* For stats purposes only. */ 1253 n_scheduling_events_MAJOR++; 1254 1255 /* Figure out how many bbs to ask vg_run_innerloop to do. Note 1256 that it decrements the counter before testing it for zero, so 1257 that if tst->dispatch_ctr is set to N you get at most N-1 1258 iterations. Also this means that tst->dispatch_ctr must 1259 exceed zero before entering the innerloop. Also also, the 1260 decrement is done before the bb is actually run, so you 1261 always get at least one decrement even if nothing happens. */ 1262 // FIXME is this right? 1263 dispatch_ctr = SCHEDULING_QUANTUM; 1264 1265 /* paranoia ... */ 1266 vg_assert(tst->tid == tid); 1267 vg_assert(tst->os_state.lwpid == VG_(gettid)()); 1268 } 1269 1270 /* For stats purposes only. */ 1271 n_scheduling_events_MINOR++; 1272 1273 if (0) 1274 VG_(message)(Vg_DebugMsg, "thread %d: running for %d bbs\n", 1275 tid, dispatch_ctr - 1 ); 1276 1277 HWord trc[2]; /* "two_words" */ 1278 run_thread_for_a_while( &trc[0], 1279 &dispatch_ctr, 1280 tid, 0/*ignored*/, False ); 1281 1282 if (VG_(clo_trace_sched) && VG_(clo_verbosity) > 2) { 1283 HChar buf[50]; 1284 VG_(sprintf)(buf, "TRC: %s", name_of_sched_event(trc[0])); 1285 print_sched_event(tid, buf); 1286 } 1287 1288 if (trc[0] == VEX_TRC_JMP_NOREDIR) { 1289 /* If we got a request to run a no-redir version of 1290 something, do so now -- handle_noredir_jump just (creates 1291 and) runs that one translation. The flip side is that the 1292 noredir translation can't itself return another noredir 1293 request -- that would be nonsensical. It can, however, 1294 return VG_TRC_BORING, which just means keep going as 1295 normal. */ 1296 /* Note that the fact that we need to continue with a 1297 no-redir jump is not recorded anywhere else in this 1298 thread's state. So we *must* execute the block right now 1299 -- we can't fail to execute it and later resume with it, 1300 because by then we'll have forgotten the fact that it 1301 should be run as no-redir, but will get run as a normal 1302 potentially-redir'd, hence screwing up. This really ought 1303 to be cleaned up, by noting in the guest state that the 1304 next block to be executed should be no-redir. Then we can 1305 suspend and resume at any point, which isn't the case at 1306 the moment. */ 1307 handle_noredir_jump( &trc[0], 1308 &dispatch_ctr, 1309 tid ); 1310 vg_assert(trc[0] != VEX_TRC_JMP_NOREDIR); 1311 1312 /* This can't be allowed to happen, since it means the block 1313 didn't execute, and we have no way to resume-as-noredir 1314 after we get more timeslice. But I don't think it ever 1315 can, since handle_noredir_jump will assert if the counter 1316 is zero on entry. */ 1317 vg_assert(trc[0] != VG_TRC_INNER_COUNTERZERO); 1318 1319 /* A no-redir translation can't return with a chain-me 1320 request, since chaining in the no-redir cache is too 1321 complex. */ 1322 vg_assert(trc[0] != VG_TRC_CHAIN_ME_TO_SLOW_EP 1323 && trc[0] != VG_TRC_CHAIN_ME_TO_FAST_EP); 1324 } 1325 1326 switch (trc[0]) { 1327 case VEX_TRC_JMP_BORING: 1328 /* assisted dispatch, no event. Used by no-redir 1329 translations to force return to the scheduler. */ 1330 case VG_TRC_BORING: 1331 /* no special event, just keep going. */ 1332 break; 1333 1334 case VG_TRC_INNER_FASTMISS: 1335 vg_assert(dispatch_ctr > 0); 1336 handle_tt_miss(tid); 1337 break; 1338 1339 case VG_TRC_CHAIN_ME_TO_SLOW_EP: { 1340 if (0) VG_(printf)("sched: CHAIN_TO_SLOW_EP: %p\n", (void*)trc[1] ); 1341 handle_chain_me(tid, (void*)trc[1], False); 1342 break; 1343 } 1344 1345 case VG_TRC_CHAIN_ME_TO_FAST_EP: { 1346 if (0) VG_(printf)("sched: CHAIN_TO_FAST_EP: %p\n", (void*)trc[1] ); 1347 handle_chain_me(tid, (void*)trc[1], True); 1348 break; 1349 } 1350 1351 case VEX_TRC_JMP_CLIENTREQ: 1352 do_client_request(tid); 1353 break; 1354 1355 case VEX_TRC_JMP_SYS_INT128: /* x86-linux */ 1356 case VEX_TRC_JMP_SYS_INT129: /* x86-darwin */ 1357 case VEX_TRC_JMP_SYS_INT130: /* x86-darwin */ 1358 case VEX_TRC_JMP_SYS_SYSCALL: /* amd64-linux, ppc32-linux, amd64-darwin */ 1359 handle_syscall(tid, trc[0]); 1360 if (VG_(clo_sanity_level) > 2) 1361 VG_(sanity_check_general)(True); /* sanity-check every syscall */ 1362 break; 1363 1364 case VEX_TRC_JMP_YIELD: 1365 /* Explicit yield, because this thread is in a spin-lock 1366 or something. Only let the thread run for a short while 1367 longer. Because swapping to another thread is expensive, 1368 we're prepared to let this thread eat a little more CPU 1369 before swapping to another. That means that short term 1370 spins waiting for hardware to poke memory won't cause a 1371 thread swap. */ 1372 if (dispatch_ctr > 1000) 1373 dispatch_ctr = 1000; 1374 break; 1375 1376 case VG_TRC_INNER_COUNTERZERO: 1377 /* Timeslice is out. Let a new thread be scheduled. */ 1378 vg_assert(dispatch_ctr == 0); 1379 break; 1380 1381 case VG_TRC_FAULT_SIGNAL: 1382 /* Everything should be set up (either we're exiting, or 1383 about to start in a signal handler). */ 1384 break; 1385 1386 case VEX_TRC_JMP_MAPFAIL: 1387 /* Failure of arch-specific address translation (x86/amd64 1388 segment override use) */ 1389 /* jrs 2005 03 11: is this correct? */ 1390 VG_(synth_fault)(tid); 1391 break; 1392 1393 case VEX_TRC_JMP_EMWARN: { 1394 static Int counts[EmNote_NUMBER]; 1395 static Bool counts_initted = False; 1396 VexEmNote ew; 1397 const HChar* what; 1398 Bool show; 1399 Int q; 1400 if (!counts_initted) { 1401 counts_initted = True; 1402 for (q = 0; q < EmNote_NUMBER; q++) 1403 counts[q] = 0; 1404 } 1405 ew = (VexEmNote)VG_(threads)[tid].arch.vex.guest_EMNOTE; 1406 what = (ew < 0 || ew >= EmNote_NUMBER) 1407 ? "unknown (?!)" 1408 : LibVEX_EmNote_string(ew); 1409 show = (ew < 0 || ew >= EmNote_NUMBER) 1410 ? True 1411 : counts[ew]++ < 3; 1412 if (show && VG_(clo_show_emwarns) && !VG_(clo_xml)) { 1413 VG_(message)( Vg_UserMsg, 1414 "Emulation warning: unsupported action:\n"); 1415 VG_(message)( Vg_UserMsg, " %s\n", what); 1416 VG_(get_and_pp_StackTrace)( tid, VG_(clo_backtrace_size) ); 1417 } 1418 break; 1419 } 1420 1421 case VEX_TRC_JMP_EMFAIL: { 1422 VexEmNote ew; 1423 const HChar* what; 1424 ew = (VexEmNote)VG_(threads)[tid].arch.vex.guest_EMNOTE; 1425 what = (ew < 0 || ew >= EmNote_NUMBER) 1426 ? "unknown (?!)" 1427 : LibVEX_EmNote_string(ew); 1428 VG_(message)( Vg_UserMsg, 1429 "Emulation fatal error -- Valgrind cannot continue:\n"); 1430 VG_(message)( Vg_UserMsg, " %s\n", what); 1431 VG_(get_and_pp_StackTrace)( tid, VG_(clo_backtrace_size) ); 1432 VG_(message)(Vg_UserMsg, "\n"); 1433 VG_(message)(Vg_UserMsg, "Valgrind has to exit now. Sorry.\n"); 1434 VG_(message)(Vg_UserMsg, "\n"); 1435 VG_(exit)(1); 1436 break; 1437 } 1438 1439 case VEX_TRC_JMP_SIGILL: 1440 VG_(synth_sigill)(tid, VG_(get_IP)(tid)); 1441 break; 1442 1443 case VEX_TRC_JMP_SIGTRAP: 1444 VG_(synth_sigtrap)(tid); 1445 break; 1446 1447 case VEX_TRC_JMP_SIGSEGV: 1448 VG_(synth_fault)(tid); 1449 break; 1450 1451 case VEX_TRC_JMP_SIGBUS: 1452 VG_(synth_sigbus)(tid); 1453 break; 1454 1455 case VEX_TRC_JMP_SIGFPE_INTDIV: 1456 VG_(synth_sigfpe)(tid, VKI_FPE_INTDIV); 1457 break; 1458 1459 case VEX_TRC_JMP_SIGFPE_INTOVF: 1460 VG_(synth_sigfpe)(tid, VKI_FPE_INTOVF); 1461 break; 1462 1463 case VEX_TRC_JMP_NODECODE: { 1464 Addr addr = VG_(get_IP)(tid); 1465 1466 if (VG_(clo_sigill_diag)) { 1467 VG_(umsg)( 1468 "valgrind: Unrecognised instruction at address %#lx.\n", addr); 1469 VG_(get_and_pp_StackTrace)(tid, VG_(clo_backtrace_size)); 1470 # define M(a) VG_(umsg)(a "\n"); 1471 M("Your program just tried to execute an instruction that Valgrind" ); 1472 M("did not recognise. There are two possible reasons for this." ); 1473 M("1. Your program has a bug and erroneously jumped to a non-code" ); 1474 M(" location. If you are running Memcheck and you just saw a" ); 1475 M(" warning about a bad jump, it's probably your program's fault."); 1476 M("2. The instruction is legitimate but Valgrind doesn't handle it,"); 1477 M(" i.e. it's Valgrind's fault. If you think this is the case or"); 1478 M(" you are not sure, please let us know and we'll try to fix it."); 1479 M("Either way, Valgrind will now raise a SIGILL signal which will" ); 1480 M("probably kill your program." ); 1481 # undef M 1482 } 1483 # if defined(VGA_s390x) 1484 /* Now that the complaint is out we need to adjust the guest_IA. The 1485 reason is that -- after raising the exception -- execution will 1486 continue with the insn that follows the invalid insn. As the first 1487 2 bits of the invalid insn determine its length in the usual way, 1488 we can compute the address of the next insn here and adjust the 1489 guest_IA accordingly. This adjustment is essential and tested by 1490 none/tests/s390x/op_exception.c (which would loop forever 1491 otherwise) */ 1492 UChar byte = ((UChar *)addr)[0]; 1493 UInt insn_length = ((((byte >> 6) + 1) >> 1) + 1) << 1; 1494 Addr next_insn_addr = addr + insn_length; 1495 VG_(set_IP)(tid, next_insn_addr); 1496 # endif 1497 VG_(synth_sigill)(tid, addr); 1498 break; 1499 } 1500 1501 case VEX_TRC_JMP_INVALICACHE: 1502 VG_(discard_translations)( 1503 (Addr64)VG_(threads)[tid].arch.vex.guest_CMSTART, 1504 VG_(threads)[tid].arch.vex.guest_CMLEN, 1505 "scheduler(VEX_TRC_JMP_INVALICACHE)" 1506 ); 1507 if (0) 1508 VG_(printf)("dump translations done.\n"); 1509 break; 1510 1511 case VEX_TRC_JMP_FLUSHDCACHE: { 1512 void* start = (void*)VG_(threads)[tid].arch.vex.guest_CMSTART; 1513 SizeT len = VG_(threads)[tid].arch.vex.guest_CMLEN; 1514 VG_(debugLog)(2, "sched", "flush_dcache(%p, %lu)\n", start, len); 1515 VG_(flush_dcache)(start, len); 1516 break; 1517 } 1518 1519 case VG_TRC_INVARIANT_FAILED: 1520 /* This typically happens if, after running generated code, 1521 it is detected that host CPU settings (eg, FPU/Vector 1522 control words) are not as they should be. Vex's code 1523 generation specifies the state such control words should 1524 be in on entry to Vex-generated code, and they should be 1525 unchanged on exit from it. Failure of this assertion 1526 usually means a bug in Vex's code generation. */ 1527 //{ UInt xx; 1528 // __asm__ __volatile__ ( 1529 // "\t.word 0xEEF12A10\n" // fmrx r2,fpscr 1530 // "\tmov %0, r2" : "=r"(xx) : : "r2" ); 1531 // VG_(printf)("QQQQ new fpscr = %08x\n", xx); 1532 //} 1533 vg_assert2(0, "VG_(scheduler), phase 3: " 1534 "run_innerloop detected host " 1535 "state invariant failure", trc); 1536 1537 case VEX_TRC_JMP_SYS_SYSENTER: 1538 /* Do whatever simulation is appropriate for an x86 sysenter 1539 instruction. Note that it is critical to set this thread's 1540 guest_EIP to point at the code to execute after the 1541 sysenter, since Vex-generated code will not have set it -- 1542 vex does not know what it should be. Vex sets the next 1543 address to zero, so if you don't set guest_EIP, the thread 1544 will jump to zero afterwards and probably die as a result. */ 1545 # if defined(VGP_x86_linux) 1546 vg_assert2(0, "VG_(scheduler), phase 3: " 1547 "sysenter_x86 on x86-linux is not supported"); 1548 # elif defined(VGP_x86_darwin) 1549 /* return address in client edx */ 1550 VG_(threads)[tid].arch.vex.guest_EIP 1551 = VG_(threads)[tid].arch.vex.guest_EDX; 1552 handle_syscall(tid, trc[0]); 1553 # else 1554 vg_assert2(0, "VG_(scheduler), phase 3: " 1555 "sysenter_x86 on non-x86 platform?!?!"); 1556 # endif 1557 break; 1558 1559 default: 1560 vg_assert2(0, "VG_(scheduler), phase 3: " 1561 "unexpected thread return code (%u)", trc[0]); 1562 /* NOTREACHED */ 1563 break; 1564 1565 } /* switch (trc) */ 1566 1567 if (UNLIKELY(VG_(clo_profyle_sbs)) && VG_(clo_profyle_interval) > 0) 1568 maybe_show_sb_profile(); 1569 } 1570 1571 if (VG_(clo_trace_sched)) 1572 print_sched_event(tid, "exiting VG_(scheduler)"); 1573 1574 vg_assert(VG_(is_exiting)(tid)); 1575 1576 return tst->exitreason; 1577 } 1578 1579 1580 /* 1581 This causes all threads to forceably exit. They aren't actually 1582 dead by the time this returns; you need to call 1583 VG_(reap_threads)() to wait for them. 1584 */ 1585 void VG_(nuke_all_threads_except) ( ThreadId me, VgSchedReturnCode src ) 1586 { 1587 ThreadId tid; 1588 1589 vg_assert(VG_(is_running_thread)(me)); 1590 1591 for (tid = 1; tid < VG_N_THREADS; tid++) { 1592 if (tid == me 1593 || VG_(threads)[tid].status == VgTs_Empty) 1594 continue; 1595 if (0) 1596 VG_(printf)( 1597 "VG_(nuke_all_threads_except): nuking tid %d\n", tid); 1598 1599 VG_(threads)[tid].exitreason = src; 1600 if (src == VgSrc_FatalSig) 1601 VG_(threads)[tid].os_state.fatalsig = VKI_SIGKILL; 1602 VG_(get_thread_out_of_syscall)(tid); 1603 } 1604 } 1605 1606 1607 /* --------------------------------------------------------------------- 1608 Specifying shadow register values 1609 ------------------------------------------------------------------ */ 1610 1611 #if defined(VGA_x86) 1612 # define VG_CLREQ_ARGS guest_EAX 1613 # define VG_CLREQ_RET guest_EDX 1614 #elif defined(VGA_amd64) 1615 # define VG_CLREQ_ARGS guest_RAX 1616 # define VG_CLREQ_RET guest_RDX 1617 #elif defined(VGA_ppc32) || defined(VGA_ppc64) 1618 # define VG_CLREQ_ARGS guest_GPR4 1619 # define VG_CLREQ_RET guest_GPR3 1620 #elif defined(VGA_arm) 1621 # define VG_CLREQ_ARGS guest_R4 1622 # define VG_CLREQ_RET guest_R3 1623 #elif defined(VGA_arm64) 1624 # define VG_CLREQ_ARGS guest_X4 1625 # define VG_CLREQ_RET guest_X3 1626 #elif defined (VGA_s390x) 1627 # define VG_CLREQ_ARGS guest_r2 1628 # define VG_CLREQ_RET guest_r3 1629 #elif defined(VGA_mips32) || defined(VGA_mips64) 1630 # define VG_CLREQ_ARGS guest_r12 1631 # define VG_CLREQ_RET guest_r11 1632 #else 1633 # error Unknown arch 1634 #endif 1635 1636 #define CLREQ_ARGS(regs) ((regs).vex.VG_CLREQ_ARGS) 1637 #define CLREQ_RET(regs) ((regs).vex.VG_CLREQ_RET) 1638 #define O_CLREQ_RET (offsetof(VexGuestArchState, VG_CLREQ_RET)) 1639 1640 // These macros write a value to a client's thread register, and tell the 1641 // tool that it's happened (if necessary). 1642 1643 #define SET_CLREQ_RETVAL(zztid, zzval) \ 1644 do { CLREQ_RET(VG_(threads)[zztid].arch) = (zzval); \ 1645 VG_TRACK( post_reg_write, \ 1646 Vg_CoreClientReq, zztid, O_CLREQ_RET, sizeof(UWord)); \ 1647 } while (0) 1648 1649 #define SET_CLCALL_RETVAL(zztid, zzval, f) \ 1650 do { CLREQ_RET(VG_(threads)[zztid].arch) = (zzval); \ 1651 VG_TRACK( post_reg_write_clientcall_return, \ 1652 zztid, O_CLREQ_RET, sizeof(UWord), f); \ 1653 } while (0) 1654 1655 1656 /* --------------------------------------------------------------------- 1657 Handle client requests. 1658 ------------------------------------------------------------------ */ 1659 1660 // OS-specific(?) client requests 1661 static Bool os_client_request(ThreadId tid, UWord *args) 1662 { 1663 Bool handled = True; 1664 1665 vg_assert(VG_(is_running_thread)(tid)); 1666 1667 switch(args[0]) { 1668 case VG_USERREQ__LIBC_FREERES_DONE: 1669 /* This is equivalent to an exit() syscall, but we don't set the 1670 exitcode (since it might already be set) */ 1671 if (0 || VG_(clo_trace_syscalls) || VG_(clo_trace_sched)) 1672 VG_(message)(Vg_DebugMsg, 1673 "__libc_freeres() done; really quitting!\n"); 1674 VG_(threads)[tid].exitreason = VgSrc_ExitThread; 1675 break; 1676 1677 default: 1678 handled = False; 1679 break; 1680 } 1681 1682 return handled; 1683 } 1684 1685 1686 /* Write out a client message, possibly including a back trace. Return 1687 the number of characters written. In case of XML output, the format 1688 string as well as any arguments it requires will be XML'ified. 1689 I.e. special characters such as the angle brackets will be translated 1690 into proper escape sequences. */ 1691 static 1692 Int print_client_message( ThreadId tid, const HChar *format, 1693 va_list *vargsp, Bool include_backtrace) 1694 { 1695 Int count; 1696 1697 if (VG_(clo_xml)) { 1698 /* Translate the format string as follows: 1699 < --> < 1700 > --> > 1701 & --> & 1702 %s --> %pS 1703 Yes, yes, it's simplified but in synch with 1704 myvprintf_str_XML_simplistic and VG_(debugLog_vprintf). 1705 */ 1706 1707 /* Allocate a buffer that is for sure large enough. */ 1708 HChar xml_format[VG_(strlen)(format) * 5 + 1]; 1709 1710 const HChar *p; 1711 HChar *q = xml_format; 1712 1713 for (p = format; *p; ++p) { 1714 switch (*p) { 1715 case '<': VG_(strcpy)(q, "<"); q += 4; break; 1716 case '>': VG_(strcpy)(q, ">"); q += 4; break; 1717 case '&': VG_(strcpy)(q, "&"); q += 5; break; 1718 case '%': 1719 /* Careful: make sure %%s stays %%s */ 1720 *q++ = *p++; 1721 if (*p == 's') { 1722 *q++ = 'p'; 1723 *q++ = 'S'; 1724 } else { 1725 *q++ = *p; 1726 } 1727 break; 1728 1729 default: 1730 *q++ = *p; 1731 break; 1732 } 1733 } 1734 *q = '\0'; 1735 1736 VG_(printf_xml)( "<clientmsg>\n" ); 1737 VG_(printf_xml)( " <tid>%d</tid>\n", tid ); 1738 VG_(printf_xml)( " <text>" ); 1739 count = VG_(vprintf_xml)( xml_format, *vargsp ); 1740 VG_(printf_xml)( " </text>\n" ); 1741 } else { 1742 count = VG_(vmessage)( Vg_ClientMsg, format, *vargsp ); 1743 VG_(message_flush)(); 1744 } 1745 1746 if (include_backtrace) 1747 VG_(get_and_pp_StackTrace)( tid, VG_(clo_backtrace_size) ); 1748 1749 if (VG_(clo_xml)) 1750 VG_(printf_xml)( "</clientmsg>\n" ); 1751 1752 return count; 1753 } 1754 1755 1756 /* Do a client request for the thread tid. After the request, tid may 1757 or may not still be runnable; if not, the scheduler will have to 1758 choose a new thread to run. 1759 */ 1760 static 1761 void do_client_request ( ThreadId tid ) 1762 { 1763 UWord* arg = (UWord*)(CLREQ_ARGS(VG_(threads)[tid].arch)); 1764 UWord req_no = arg[0]; 1765 1766 if (0) 1767 VG_(printf)("req no = 0x%llx, arg = %p\n", (ULong)req_no, arg); 1768 switch (req_no) { 1769 1770 case VG_USERREQ__CLIENT_CALL0: { 1771 UWord (*f)(ThreadId) = (void*)arg[1]; 1772 if (f == NULL) 1773 VG_(message)(Vg_DebugMsg, "VG_USERREQ__CLIENT_CALL0: func=%p\n", f); 1774 else 1775 SET_CLCALL_RETVAL(tid, f ( tid ), (Addr)f); 1776 break; 1777 } 1778 case VG_USERREQ__CLIENT_CALL1: { 1779 UWord (*f)(ThreadId, UWord) = (void*)arg[1]; 1780 if (f == NULL) 1781 VG_(message)(Vg_DebugMsg, "VG_USERREQ__CLIENT_CALL1: func=%p\n", f); 1782 else 1783 SET_CLCALL_RETVAL(tid, f ( tid, arg[2] ), (Addr)f ); 1784 break; 1785 } 1786 case VG_USERREQ__CLIENT_CALL2: { 1787 UWord (*f)(ThreadId, UWord, UWord) = (void*)arg[1]; 1788 if (f == NULL) 1789 VG_(message)(Vg_DebugMsg, "VG_USERREQ__CLIENT_CALL2: func=%p\n", f); 1790 else 1791 SET_CLCALL_RETVAL(tid, f ( tid, arg[2], arg[3] ), (Addr)f ); 1792 break; 1793 } 1794 case VG_USERREQ__CLIENT_CALL3: { 1795 UWord (*f)(ThreadId, UWord, UWord, UWord) = (void*)arg[1]; 1796 if (f == NULL) 1797 VG_(message)(Vg_DebugMsg, "VG_USERREQ__CLIENT_CALL3: func=%p\n", f); 1798 else 1799 SET_CLCALL_RETVAL(tid, f ( tid, arg[2], arg[3], arg[4] ), (Addr)f ); 1800 break; 1801 } 1802 1803 // Nb: this looks like a circular definition, because it kind of is. 1804 // See comment in valgrind.h to understand what's going on. 1805 case VG_USERREQ__RUNNING_ON_VALGRIND: 1806 SET_CLREQ_RETVAL(tid, RUNNING_ON_VALGRIND+1); 1807 break; 1808 1809 case VG_USERREQ__PRINTF: { 1810 const HChar* format = (HChar *)arg[1]; 1811 /* JRS 2010-Jan-28: this is DEPRECATED; use the 1812 _VALIST_BY_REF version instead */ 1813 if (sizeof(va_list) != sizeof(UWord)) 1814 goto va_list_casting_error_NORETURN; 1815 union { 1816 va_list vargs; 1817 unsigned long uw; 1818 } u; 1819 u.uw = (unsigned long)arg[2]; 1820 Int count = 1821 print_client_message( tid, format, &u.vargs, 1822 /* include_backtrace */ False ); 1823 SET_CLREQ_RETVAL( tid, count ); 1824 break; 1825 } 1826 1827 case VG_USERREQ__PRINTF_BACKTRACE: { 1828 const HChar* format = (HChar *)arg[1]; 1829 /* JRS 2010-Jan-28: this is DEPRECATED; use the 1830 _VALIST_BY_REF version instead */ 1831 if (sizeof(va_list) != sizeof(UWord)) 1832 goto va_list_casting_error_NORETURN; 1833 union { 1834 va_list vargs; 1835 unsigned long uw; 1836 } u; 1837 u.uw = (unsigned long)arg[2]; 1838 Int count = 1839 print_client_message( tid, format, &u.vargs, 1840 /* include_backtrace */ True ); 1841 SET_CLREQ_RETVAL( tid, count ); 1842 break; 1843 } 1844 1845 case VG_USERREQ__PRINTF_VALIST_BY_REF: { 1846 const HChar* format = (HChar *)arg[1]; 1847 va_list* vargsp = (va_list*)arg[2]; 1848 Int count = 1849 print_client_message( tid, format, vargsp, 1850 /* include_backtrace */ False ); 1851 1852 SET_CLREQ_RETVAL( tid, count ); 1853 break; 1854 } 1855 1856 case VG_USERREQ__PRINTF_BACKTRACE_VALIST_BY_REF: { 1857 const HChar* format = (HChar *)arg[1]; 1858 va_list* vargsp = (va_list*)arg[2]; 1859 Int count = 1860 print_client_message( tid, format, vargsp, 1861 /* include_backtrace */ True ); 1862 SET_CLREQ_RETVAL( tid, count ); 1863 break; 1864 } 1865 1866 case VG_USERREQ__INTERNAL_PRINTF_VALIST_BY_REF: { 1867 va_list* vargsp = (va_list*)arg[2]; 1868 Int count = 1869 VG_(vmessage)( Vg_DebugMsg, (HChar *)arg[1], *vargsp ); 1870 VG_(message_flush)(); 1871 SET_CLREQ_RETVAL( tid, count ); 1872 break; 1873 } 1874 1875 case VG_USERREQ__ADD_IFUNC_TARGET: { 1876 VG_(redir_add_ifunc_target)( arg[1], arg[2] ); 1877 SET_CLREQ_RETVAL( tid, 0); 1878 break; } 1879 1880 case VG_USERREQ__STACK_REGISTER: { 1881 UWord sid = VG_(register_stack)((Addr)arg[1], (Addr)arg[2]); 1882 SET_CLREQ_RETVAL( tid, sid ); 1883 break; } 1884 1885 case VG_USERREQ__STACK_DEREGISTER: { 1886 VG_(deregister_stack)(arg[1]); 1887 SET_CLREQ_RETVAL( tid, 0 ); /* return value is meaningless */ 1888 break; } 1889 1890 case VG_USERREQ__STACK_CHANGE: { 1891 VG_(change_stack)(arg[1], (Addr)arg[2], (Addr)arg[3]); 1892 SET_CLREQ_RETVAL( tid, 0 ); /* return value is meaningless */ 1893 break; } 1894 1895 case VG_USERREQ__GET_MALLOCFUNCS: { 1896 struct vg_mallocfunc_info *info = (struct vg_mallocfunc_info *)arg[1]; 1897 1898 info->tl_malloc = VG_(tdict).tool_malloc; 1899 info->tl_calloc = VG_(tdict).tool_calloc; 1900 info->tl_realloc = VG_(tdict).tool_realloc; 1901 info->tl_memalign = VG_(tdict).tool_memalign; 1902 info->tl___builtin_new = VG_(tdict).tool___builtin_new; 1903 info->tl___builtin_vec_new = VG_(tdict).tool___builtin_vec_new; 1904 info->tl_free = VG_(tdict).tool_free; 1905 info->tl___builtin_delete = VG_(tdict).tool___builtin_delete; 1906 info->tl___builtin_vec_delete = VG_(tdict).tool___builtin_vec_delete; 1907 info->tl_malloc_usable_size = VG_(tdict).tool_malloc_usable_size; 1908 1909 info->mallinfo = VG_(mallinfo); 1910 info->clo_trace_malloc = VG_(clo_trace_malloc); 1911 1912 SET_CLREQ_RETVAL( tid, 0 ); /* return value is meaningless */ 1913 1914 break; 1915 } 1916 1917 /* Requests from the client program */ 1918 1919 case VG_USERREQ__DISCARD_TRANSLATIONS: 1920 if (VG_(clo_verbosity) > 2) 1921 VG_(printf)( "client request: DISCARD_TRANSLATIONS," 1922 " addr %p, len %lu\n", 1923 (void*)arg[1], arg[2] ); 1924 1925 VG_(discard_translations)( 1926 arg[1], arg[2], "scheduler(VG_USERREQ__DISCARD_TRANSLATIONS)" 1927 ); 1928 1929 SET_CLREQ_RETVAL( tid, 0 ); /* return value is meaningless */ 1930 break; 1931 1932 case VG_USERREQ__COUNT_ERRORS: 1933 SET_CLREQ_RETVAL( tid, VG_(get_n_errs_found)() ); 1934 break; 1935 1936 case VG_USERREQ__LOAD_PDB_DEBUGINFO: 1937 VG_(di_notify_pdb_debuginfo)( arg[1], arg[2], arg[3], arg[4] ); 1938 SET_CLREQ_RETVAL( tid, 0 ); /* return value is meaningless */ 1939 break; 1940 1941 case VG_USERREQ__MAP_IP_TO_SRCLOC: { 1942 Addr ip = arg[1]; 1943 HChar* buf64 = (HChar*)arg[2]; 1944 1945 VG_(memset)(buf64, 0, 64); 1946 UInt linenum = 0; 1947 Bool ok = VG_(get_filename_linenum)( 1948 ip, &buf64[0], 50, NULL, 0, NULL, &linenum 1949 ); 1950 if (ok) { 1951 /* Find the terminating zero in the first 50 bytes. */ 1952 UInt i; 1953 for (i = 0; i < 50; i++) { 1954 if (buf64[i] == 0) 1955 break; 1956 } 1957 /* We must find a zero somewhere in 0 .. 49. Else 1958 VG_(get_filename_linenum) is not properly zero 1959 terminating. */ 1960 vg_assert(i < 50); 1961 VG_(sprintf)(&buf64[i], ":%u", linenum); 1962 } else { 1963 buf64[0] = 0; 1964 } 1965 1966 SET_CLREQ_RETVAL( tid, 0 ); /* return value is meaningless */ 1967 break; 1968 } 1969 1970 case VG_USERREQ__CHANGE_ERR_DISABLEMENT: { 1971 Word delta = arg[1]; 1972 vg_assert(delta == 1 || delta == -1); 1973 ThreadState* tst = VG_(get_ThreadState)(tid); 1974 vg_assert(tst); 1975 if (delta == 1 && tst->err_disablement_level < 0xFFFFFFFF) { 1976 tst->err_disablement_level++; 1977 } 1978 else 1979 if (delta == -1 && tst->err_disablement_level > 0) { 1980 tst->err_disablement_level--; 1981 } 1982 SET_CLREQ_RETVAL( tid, 0 ); /* return value is meaningless */ 1983 break; 1984 } 1985 1986 case VG_USERREQ__GDB_MONITOR_COMMAND: { 1987 UWord ret; 1988 ret = (UWord) VG_(client_monitor_command) ((HChar*)arg[1]); 1989 SET_CLREQ_RETVAL(tid, ret); 1990 break; 1991 } 1992 1993 case VG_USERREQ__MALLOCLIKE_BLOCK: 1994 case VG_USERREQ__RESIZEINPLACE_BLOCK: 1995 case VG_USERREQ__FREELIKE_BLOCK: 1996 // Ignore them if the addr is NULL; otherwise pass onto the tool. 1997 if (!arg[1]) { 1998 SET_CLREQ_RETVAL( tid, 0 ); /* return value is meaningless */ 1999 break; 2000 } else { 2001 goto my_default; 2002 } 2003 2004 case VG_USERREQ__VEX_INIT_FOR_IRI: 2005 LibVEX_InitIRI ( (IRICB *)arg[1] ); 2006 break; 2007 2008 default: 2009 my_default: 2010 if (os_client_request(tid, arg)) { 2011 // do nothing, os_client_request() handled it 2012 } else if (VG_(needs).client_requests) { 2013 UWord ret; 2014 2015 if (VG_(clo_verbosity) > 2) 2016 VG_(printf)("client request: code %lx, addr %p, len %lu\n", 2017 arg[0], (void*)arg[1], arg[2] ); 2018 2019 if ( VG_TDICT_CALL(tool_handle_client_request, tid, arg, &ret) ) 2020 SET_CLREQ_RETVAL(tid, ret); 2021 } else { 2022 static Bool whined = False; 2023 2024 if (!whined && VG_(clo_verbosity) > 2) { 2025 // Allow for requests in core, but defined by tools, which 2026 // have 0 and 0 in their two high bytes. 2027 HChar c1 = (arg[0] >> 24) & 0xff; 2028 HChar c2 = (arg[0] >> 16) & 0xff; 2029 if (c1 == 0) c1 = '_'; 2030 if (c2 == 0) c2 = '_'; 2031 VG_(message)(Vg_UserMsg, "Warning:\n" 2032 " unhandled client request: 0x%lx (%c%c+0x%lx). Perhaps\n" 2033 " VG_(needs).client_requests should be set?\n", 2034 arg[0], c1, c2, arg[0] & 0xffff); 2035 whined = True; 2036 } 2037 } 2038 break; 2039 } 2040 return; 2041 2042 /*NOTREACHED*/ 2043 va_list_casting_error_NORETURN: 2044 VG_(umsg)( 2045 "Valgrind: fatal error - cannot continue: use of the deprecated\n" 2046 "client requests VG_USERREQ__PRINTF or VG_USERREQ__PRINTF_BACKTRACE\n" 2047 "on a platform where they cannot be supported. Please use the\n" 2048 "equivalent _VALIST_BY_REF versions instead.\n" 2049 "\n" 2050 "This is a binary-incompatible change in Valgrind's client request\n" 2051 "mechanism. It is unfortunate, but difficult to avoid. End-users\n" 2052 "are expected to almost never see this message. The only case in\n" 2053 "which you might see this message is if your code uses the macros\n" 2054 "VALGRIND_PRINTF or VALGRIND_PRINTF_BACKTRACE. If so, you will need\n" 2055 "to recompile such code, using the header files from this version of\n" 2056 "Valgrind, and not any previous version.\n" 2057 "\n" 2058 "If you see this mesage in any other circumstances, it is probably\n" 2059 "a bug in Valgrind. In this case, please file a bug report at\n" 2060 "\n" 2061 " http://www.valgrind.org/support/bug_reports.html\n" 2062 "\n" 2063 "Will now abort.\n" 2064 ); 2065 vg_assert(0); 2066 } 2067 2068 2069 /* --------------------------------------------------------------------- 2070 Sanity checking (permanently engaged) 2071 ------------------------------------------------------------------ */ 2072 2073 /* Internal consistency checks on the sched structures. */ 2074 static 2075 void scheduler_sanity ( ThreadId tid ) 2076 { 2077 Bool bad = False; 2078 Int lwpid = VG_(gettid)(); 2079 2080 if (!VG_(is_running_thread)(tid)) { 2081 VG_(message)(Vg_DebugMsg, 2082 "Thread %d is supposed to be running, " 2083 "but doesn't own the_BigLock (owned by %d)\n", 2084 tid, VG_(running_tid)); 2085 bad = True; 2086 } 2087 2088 if (lwpid != VG_(threads)[tid].os_state.lwpid) { 2089 VG_(message)(Vg_DebugMsg, 2090 "Thread %d supposed to be in LWP %d, but we're actually %d\n", 2091 tid, VG_(threads)[tid].os_state.lwpid, VG_(gettid)()); 2092 bad = True; 2093 } 2094 2095 if (lwpid != ML_(get_sched_lock_owner)(the_BigLock)) { 2096 VG_(message)(Vg_DebugMsg, 2097 "Thread (LWPID) %d doesn't own the_BigLock\n", 2098 tid); 2099 bad = True; 2100 } 2101 2102 if (0) { 2103 /* Periodically show the state of all threads, for debugging 2104 purposes. */ 2105 static UInt lasttime = 0; 2106 UInt now; 2107 now = VG_(read_millisecond_timer)(); 2108 if ((!bad) && (lasttime + 4000/*ms*/ <= now)) { 2109 lasttime = now; 2110 VG_(printf)("\n------------ Sched State at %d ms ------------\n", 2111 (Int)now); 2112 VG_(show_sched_status)(True, // host_stacktrace 2113 True, // valgrind_stack_usage 2114 True); // exited_threads); 2115 } 2116 } 2117 2118 /* core_panic also shows the sched status, which is why we don't 2119 show it above if bad==True. */ 2120 if (bad) 2121 VG_(core_panic)("scheduler_sanity: failed"); 2122 } 2123 2124 void VG_(sanity_check_general) ( Bool force_expensive ) 2125 { 2126 ThreadId tid; 2127 2128 static UInt next_slow_check_at = 1; 2129 static UInt slow_check_interval = 25; 2130 2131 if (VG_(clo_sanity_level) < 1) return; 2132 2133 /* --- First do all the tests that we can do quickly. ---*/ 2134 2135 sanity_fast_count++; 2136 2137 /* Check stuff pertaining to the memory check system. */ 2138 2139 /* Check that nobody has spuriously claimed that the first or 2140 last 16 pages of memory have become accessible [...] */ 2141 if (VG_(needs).sanity_checks) { 2142 vg_assert(VG_TDICT_CALL(tool_cheap_sanity_check)); 2143 } 2144 2145 /* --- Now some more expensive checks. ---*/ 2146 2147 /* Once every now and again, check some more expensive stuff. 2148 Gradually increase the interval between such checks so as not to 2149 burden long-running programs too much. */ 2150 if ( force_expensive 2151 || VG_(clo_sanity_level) > 1 2152 || (VG_(clo_sanity_level) == 1 2153 && sanity_fast_count == next_slow_check_at)) { 2154 2155 if (0) VG_(printf)("SLOW at %d\n", sanity_fast_count-1); 2156 2157 next_slow_check_at = sanity_fast_count - 1 + slow_check_interval; 2158 slow_check_interval++; 2159 sanity_slow_count++; 2160 2161 if (VG_(needs).sanity_checks) { 2162 vg_assert(VG_TDICT_CALL(tool_expensive_sanity_check)); 2163 } 2164 2165 /* Look for stack overruns. Visit all threads. */ 2166 for (tid = 1; tid < VG_N_THREADS; tid++) { 2167 SizeT remains; 2168 VgStack* stack; 2169 2170 if (VG_(threads)[tid].status == VgTs_Empty || 2171 VG_(threads)[tid].status == VgTs_Zombie) 2172 continue; 2173 2174 stack 2175 = (VgStack*) 2176 VG_(get_ThreadState)(tid)->os_state.valgrind_stack_base; 2177 SizeT limit 2178 = 4096; // Let's say. Checking more causes lots of L2 misses. 2179 remains 2180 = VG_(am_get_VgStack_unused_szB)(stack, limit); 2181 if (remains < limit) 2182 VG_(message)(Vg_DebugMsg, 2183 "WARNING: Thread %d is within %ld bytes " 2184 "of running out of stack!\n", 2185 tid, remains); 2186 } 2187 } 2188 2189 if (VG_(clo_sanity_level) > 1) { 2190 /* Check sanity of the low-level memory manager. Note that bugs 2191 in the client's code can cause this to fail, so we don't do 2192 this check unless specially asked for. And because it's 2193 potentially very expensive. */ 2194 VG_(sanity_check_malloc_all)(); 2195 } 2196 } 2197 2198 /*--------------------------------------------------------------------*/ 2199 /*--- end ---*/ 2200 /*--------------------------------------------------------------------*/ 2201
