1/*
2  This file is part of drd, a thread error detector.
3
4  Copyright (C) 2006-2013 Bart Van Assche <bvanassche@acm.org>.
5
6  This program is free software; you can redistribute it and/or
7  modify it under the terms of the GNU General Public License as
8  published by the Free Software Foundation; either version 2 of the
9  License, or (at your option) any later version.
10
11  This program is distributed in the hope that it will be useful, but
12  WITHOUT ANY WARRANTY; without even the implied warranty of
13  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  General Public License for more details.
15
16  You should have received a copy of the GNU General Public License
17  along with this program; if not, write to the Free Software
18  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
19  02111-1307, USA.
20
21  The GNU General Public License is contained in the file COPYING.
22*/
23
24
25#include "drd_barrier.h"
26#include "drd_clientobj.h"
27#include "drd_clientreq.h"
28#include "drd_cond.h"
29#include "drd_error.h"
30#include "drd_hb.h"
31#include "drd_load_store.h"
32#include "drd_malloc_wrappers.h"
33#include "drd_mutex.h"
34#include "drd_rwlock.h"
35#include "drd_segment.h"
36#include "drd_semaphore.h"
37#include "drd_suppression.h"
38#include "drd_thread.h"
39#include "libvex_guest_offsets.h"
40#include "pub_drd_bitmap.h"
41#include "pub_tool_vki.h"         // Must be included before pub_tool_libcproc
42#include "pub_tool_basics.h"
43#include "pub_tool_debuginfo.h"   // VG_(describe_IP)()
44#include "pub_tool_libcassert.h"  // tl_assert()
45#include "pub_tool_libcbase.h"    // VG_(strcmp)
46#include "pub_tool_libcprint.h"   // VG_(printf)
47#include "pub_tool_libcproc.h"
48#include "pub_tool_machine.h"
49#include "pub_tool_mallocfree.h"  // VG_(malloc)(), VG_(free)()
50#include "pub_tool_options.h"     // command line options
51#include "pub_tool_replacemalloc.h"
52#include "pub_tool_threadstate.h" // VG_(get_running_tid)()
53#include "pub_tool_tooliface.h"
54#include "pub_tool_aspacemgr.h"   // VG_(am_is_valid_for_client)
55
56
57/* Local variables. */
58
59static Bool s_print_stats;
60static Bool s_var_info;
61static Bool s_show_stack_usage;
62static Bool s_trace_alloc;
63static Bool trace_sectsuppr;
64
65
66/**
67 * Implement the needs_command_line_options for drd.
68 */
69static Bool DRD_(process_cmd_line_option)(const HChar* arg)
70{
71   int check_stack_accesses   = -1;
72   int join_list_vol          = -1;
73   int exclusive_threshold_ms = -1;
74   int first_race_only        = -1;
75   int report_signal_unlocked = -1;
76   int segment_merging        = -1;
77   int segment_merge_interval = -1;
78   int shared_threshold_ms    = -1;
79   int show_confl_seg         = -1;
80   int trace_barrier          = -1;
81   int trace_clientobj        = -1;
82   int trace_cond             = -1;
83   int trace_csw              = -1;
84   int trace_fork_join        = -1;
85   int trace_hb               = -1;
86   int trace_conflict_set     = -1;
87   int trace_conflict_set_bm  = -1;
88   int trace_mutex            = -1;
89   int trace_rwlock           = -1;
90   int trace_segment          = -1;
91   int trace_semaphore        = -1;
92   int trace_suppression      = -1;
93   const HChar* trace_address = 0;
94   const HChar* ptrace_address= 0;
95
96   if      VG_BOOL_CLO(arg, "--check-stack-var",     check_stack_accesses) {}
97   else if VG_INT_CLO (arg, "--join-list-vol",       join_list_vol) {}
98   else if VG_BOOL_CLO(arg, "--drd-stats",           s_print_stats) {}
99   else if VG_BOOL_CLO(arg, "--first-race-only",     first_race_only) {}
100   else if VG_BOOL_CLO(arg, "--free-is-write",       DRD_(g_free_is_write)) {}
101   else if VG_BOOL_CLO(arg,"--report-signal-unlocked",report_signal_unlocked)
102   {}
103   else if VG_BOOL_CLO(arg, "--segment-merging",     segment_merging) {}
104   else if VG_INT_CLO (arg, "--segment-merging-interval", segment_merge_interval)
105   {}
106   else if VG_BOOL_CLO(arg, "--show-confl-seg",      show_confl_seg) {}
107   else if VG_BOOL_CLO(arg, "--show-stack-usage",    s_show_stack_usage) {}
108   else if VG_BOOL_CLO(arg, "--trace-alloc",         s_trace_alloc) {}
109   else if VG_BOOL_CLO(arg, "--trace-barrier",       trace_barrier) {}
110   else if VG_BOOL_CLO(arg, "--trace-clientobj",     trace_clientobj) {}
111   else if VG_BOOL_CLO(arg, "--trace-cond",          trace_cond) {}
112   else if VG_BOOL_CLO(arg, "--trace-conflict-set",  trace_conflict_set) {}
113   else if VG_BOOL_CLO(arg, "--trace-conflict-set-bm", trace_conflict_set_bm){}
114   else if VG_BOOL_CLO(arg, "--trace-csw",           trace_csw) {}
115   else if VG_BOOL_CLO(arg, "--trace-fork-join",     trace_fork_join) {}
116   else if VG_BOOL_CLO(arg, "--trace-hb",            trace_hb) {}
117   else if VG_BOOL_CLO(arg, "--trace-mutex",         trace_mutex) {}
118   else if VG_BOOL_CLO(arg, "--trace-rwlock",        trace_rwlock) {}
119   else if VG_BOOL_CLO(arg, "--trace-sectsuppr",     trace_sectsuppr) {}
120   else if VG_BOOL_CLO(arg, "--trace-segment",       trace_segment) {}
121   else if VG_BOOL_CLO(arg, "--trace-semaphore",     trace_semaphore) {}
122   else if VG_BOOL_CLO(arg, "--trace-suppr",         trace_suppression) {}
123   else if VG_BOOL_CLO(arg, "--var-info",            s_var_info) {}
124   else if VG_INT_CLO (arg, "--exclusive-threshold", exclusive_threshold_ms) {}
125   else if VG_STR_CLO (arg, "--ptrace-addr",         ptrace_address) {}
126   else if VG_INT_CLO (arg, "--shared-threshold",    shared_threshold_ms)    {}
127   else if VG_STR_CLO (arg, "--trace-addr",          trace_address) {}
128   else
129      return VG_(replacement_malloc_process_cmd_line_option)(arg);
130
131   if (check_stack_accesses != -1)
132      DRD_(set_check_stack_accesses)(check_stack_accesses);
133   if (exclusive_threshold_ms != -1)
134   {
135      DRD_(mutex_set_lock_threshold)(exclusive_threshold_ms);
136      DRD_(rwlock_set_exclusive_threshold)(exclusive_threshold_ms);
137   }
138   if (first_race_only != -1)
139   {
140      DRD_(set_first_race_only)(first_race_only);
141   }
142   if (join_list_vol != -1)
143      DRD_(thread_set_join_list_vol)(join_list_vol);
144   if (report_signal_unlocked != -1)
145   {
146      DRD_(cond_set_report_signal_unlocked)(report_signal_unlocked);
147   }
148   if (shared_threshold_ms != -1)
149   {
150      DRD_(rwlock_set_shared_threshold)(shared_threshold_ms);
151   }
152   if (segment_merging != -1)
153      DRD_(thread_set_segment_merging)(segment_merging);
154   if (segment_merge_interval != -1)
155      DRD_(thread_set_segment_merge_interval)(segment_merge_interval);
156   if (show_confl_seg != -1)
157      DRD_(set_show_conflicting_segments)(show_confl_seg);
158   if (trace_address) {
159      const Addr addr = VG_(strtoll16)(trace_address, 0);
160      DRD_(start_tracing_address_range)(addr, addr + 1, False);
161   }
162   if (ptrace_address) {
163      char *plus = VG_(strchr)(ptrace_address, '+');
164      Addr addr, length;
165      if (plus)
166         *plus = '\0';
167      addr = VG_(strtoll16)(ptrace_address, 0);
168      length = plus ? VG_(strtoll16)(plus + 1, 0) : 1;
169      DRD_(start_tracing_address_range)(addr, addr + length, True);
170   }
171   if (trace_barrier != -1)
172      DRD_(barrier_set_trace)(trace_barrier);
173   if (trace_clientobj != -1)
174      DRD_(clientobj_set_trace)(trace_clientobj);
175   if (trace_cond != -1)
176      DRD_(cond_set_trace)(trace_cond);
177   if (trace_csw != -1)
178      DRD_(thread_trace_context_switches)(trace_csw);
179   if (trace_fork_join != -1)
180      DRD_(thread_set_trace_fork_join)(trace_fork_join);
181   if (trace_hb != -1)
182      DRD_(hb_set_trace)(trace_hb);
183   if (trace_conflict_set != -1)
184      DRD_(thread_trace_conflict_set)(trace_conflict_set);
185   if (trace_conflict_set_bm != -1)
186      DRD_(thread_trace_conflict_set_bm)(trace_conflict_set_bm);
187   if (trace_mutex != -1)
188      DRD_(mutex_set_trace)(trace_mutex);
189   if (trace_rwlock != -1)
190      DRD_(rwlock_set_trace)(trace_rwlock);
191   if (trace_segment != -1)
192      DRD_(sg_set_trace)(trace_segment);
193   if (trace_semaphore != -1)
194      DRD_(semaphore_set_trace)(trace_semaphore);
195   if (trace_suppression != -1)
196      DRD_(suppression_set_trace)(trace_suppression);
197
198   return True;
199}
200
201static void DRD_(print_usage)(void)
202{
203   VG_(printf)(
204"    --check-stack-var=yes|no  Whether or not to report data races on\n"
205"                              stack variables [no].\n"
206"    --exclusive-threshold=<n> Print an error message if any mutex or\n"
207"                              writer lock is held longer than the specified\n"
208"                              time (in milliseconds) [off].\n"
209"    --first-race-only=yes|no  Only report the first data race that occurs on\n"
210"                              a memory location instead of all races [no].\n"
211"    --free-is-write=yes|no    Whether to report races between freeing memory\n"
212"                              and subsequent accesses of that memory[no].\n"
213"    --join-list-vol=<n>       Number of threads to delay cleanup for [10].\n"
214"    --report-signal-unlocked=yes|no Whether to report calls to\n"
215"                              pthread_cond_signal() where the mutex associated\n"
216"                              with the signal via pthread_cond_wait() is not\n"
217"                              locked at the time the signal is sent [yes].\n"
218"    --segment-merging=yes|no  Controls segment merging [yes].\n"
219"        Segment merging is an algorithm to limit memory usage of the\n"
220"        data race detection algorithm. Disabling segment merging may\n"
221"        improve the accuracy of the so-called 'other segments' displayed\n"
222"        in race reports but can also trigger an out of memory error.\n"
223"    --segment-merging-interval=<n> Perform segment merging every time n new\n"
224"        segments have been created. Default: %d.\n"
225"    --shared-threshold=<n>    Print an error message if a reader lock\n"
226"                              is held longer than the specified time (in\n"
227"                              milliseconds) [off]\n"
228"    --show-confl-seg=yes|no   Show conflicting segments in race reports [yes].\n"
229"    --show-stack-usage=yes|no Print stack usage at thread exit time [no].\n"
230"\n"
231"  drd options for monitoring process behavior:\n"
232"    --ptrace-addr=<address>[+<length>] Trace all load and store activity for\n"
233"                              the specified address range and keep doing that\n"
234"                              even after the memory at that address has been\n"
235"                              freed and reallocated [off].\n"
236"    --trace-addr=<address>    Trace all load and store activity for the\n"
237"                              specified address [off].\n"
238"    --trace-alloc=yes|no      Trace all memory allocations and deallocations\n"
239"                              [no].\n"
240"    --trace-barrier=yes|no    Trace all barrier activity [no].\n"
241"    --trace-cond=yes|no       Trace all condition variable activity [no].\n"
242"    --trace-fork-join=yes|no  Trace all thread fork/join activity [no].\n"
243"    --trace-hb=yes|no         Trace ANNOTATE_HAPPENS_BEFORE() etc. [no].\n"
244"    --trace-mutex=yes|no      Trace all mutex activity [no].\n"
245"    --trace-rwlock=yes|no     Trace all reader-writer lock activity[no].\n"
246"    --trace-semaphore=yes|no  Trace all semaphore activity [no].\n",
247DRD_(thread_get_segment_merge_interval)()
248);
249}
250
251static void DRD_(print_debug_usage)(void)
252{
253   VG_(printf)(
254"    --drd-stats=yes|no        Print statistics about DRD activity [no].\n"
255"    --trace-clientobj=yes|no  Trace all client object activity [no].\n"
256"    --trace-csw=yes|no        Trace all scheduler context switches [no].\n"
257"    --trace-conflict-set=yes|no Trace all conflict set updates [no].\n"
258"    --trace-conflict-set-bm=yes|no Trace all conflict set bitmap\n"
259"                              updates [no]. Note: enabling this option\n"
260"                              will generate a lot of output !\n"
261"    --trace-sectsuppr=yes|no  Trace which the dynamic library sections on\n"
262"                              which data race detection is suppressed.\n"
263"    --trace-segment=yes|no    Trace segment actions [no].\n"
264"    --trace-suppr=yes|no      Trace all address suppression actions [no].\n"
265);
266}
267
268
269//
270// Implements the thread-related core callbacks.
271//
272
273static void drd_pre_mem_read(const CorePart part,
274                             const ThreadId tid,
275                             const HChar* const s,
276                             const Addr a,
277                             const SizeT size)
278{
279   DRD_(thread_set_vg_running_tid)(VG_(get_running_tid)());
280   if (size > 0)
281   {
282      DRD_(trace_load)(a, size);
283   }
284}
285
286static void drd_pre_mem_read_asciiz(const CorePart part,
287                                    const ThreadId tid,
288                                    const HChar* const s,
289                                    const Addr a)
290{
291   const HChar* p = (void*)a;
292   SizeT size = 0;
293
294   // Don't segfault if the string starts in an obviously stupid
295   // place.  Actually we should check the whole string, not just
296   // the start address, but that's too much trouble.  At least
297   // checking the first byte is better than nothing.  See #255009.
298   if (!VG_(am_is_valid_for_client) (a, 1, VKI_PROT_READ))
299      return;
300
301   /* Note: the expression '*p' reads client memory and may crash if the */
302   /* client provided an invalid pointer !                               */
303   while (*p)
304   {
305      p++;
306      size++;
307   }
308   if (size > 0)
309   {
310      DRD_(trace_load)(a, size);
311   }
312}
313
314static void drd_post_mem_write(const CorePart part,
315                               const ThreadId tid,
316                               const Addr a,
317                               const SizeT size)
318{
319   DRD_(thread_set_vg_running_tid)(VG_(get_running_tid)());
320   if (size > 0)
321   {
322      DRD_(trace_store)(a, size);
323   }
324}
325
326static __inline__
327void drd_start_using_mem(const Addr a1, const SizeT len,
328                         const Bool is_stack_mem)
329{
330   const Addr a2 = a1 + len;
331
332   tl_assert(a1 <= a2);
333
334   if (!is_stack_mem && s_trace_alloc)
335      DRD_(trace_msg)("Started using memory range 0x%lx + %ld%s",
336                      a1, len, DRD_(running_thread_inside_pthread_create)()
337                      ? " (inside pthread_create())" : "");
338
339   if (!is_stack_mem && DRD_(g_free_is_write))
340      DRD_(thread_stop_using_mem)(a1, a2);
341
342   if (UNLIKELY(DRD_(any_address_is_traced)()))
343   {
344      DRD_(trace_mem_access)(a1, len, eStart, 0, 0);
345   }
346
347   if (UNLIKELY(DRD_(running_thread_inside_pthread_create)()))
348   {
349      DRD_(start_suppression)(a1, a2, "pthread_create()");
350   }
351}
352
353static void drd_start_using_mem_w_ecu(const Addr a1,
354                                      const SizeT len,
355                                      UInt ec_uniq)
356{
357   drd_start_using_mem(a1, len, False);
358}
359
360static void drd_start_using_mem_w_tid(const Addr a1,
361                                      const SizeT len,
362                                      ThreadId tid)
363{
364   drd_start_using_mem(a1, len, False);
365}
366
367static __inline__
368void drd_stop_using_mem(const Addr a1, const SizeT len,
369                        const Bool is_stack_mem)
370{
371   const Addr a2 = a1 + len;
372
373   tl_assert(a1 <= a2);
374
375   if (UNLIKELY(DRD_(any_address_is_traced)()))
376      DRD_(trace_mem_access)(a1, len, eEnd, 0, 0);
377
378   if (!is_stack_mem && s_trace_alloc)
379      DRD_(trace_msg)("Stopped using memory range 0x%lx + %ld",
380                      a1, len);
381
382   if (!is_stack_mem || DRD_(get_check_stack_accesses)())
383   {
384      if (is_stack_mem || !DRD_(g_free_is_write))
385	 DRD_(thread_stop_using_mem)(a1, a2);
386      else if (DRD_(g_free_is_write))
387	 DRD_(trace_store)(a1, len);
388      DRD_(clientobj_stop_using_mem)(a1, a2);
389      DRD_(suppression_stop_using_mem)(a1, a2);
390   }
391}
392
393static __inline__
394void drd_stop_using_nonstack_mem(const Addr a1, const SizeT len)
395{
396   drd_stop_using_mem(a1, len, False);
397}
398
399/**
400 * Discard all information DRD has about memory accesses and client objects
401 * in the specified address range.
402 */
403void DRD_(clean_memory)(const Addr a1, const SizeT len)
404{
405   const Bool is_stack_memory = DRD_(thread_address_on_any_stack)(a1);
406   drd_stop_using_mem(a1, len, is_stack_memory);
407   drd_start_using_mem(a1, len, is_stack_memory);
408}
409
410/**
411 * Suppress data race reports on all addresses contained in .plt, .got and
412 * .got.plt sections inside the address range [ a, a + len [. The data in
413 * these sections is modified by _dl_relocate_object() every time a function
414 * in a shared library is called for the first time. Since the first call
415 * to a function in a shared library can happen from a multithreaded context,
416 * such calls can cause conflicting accesses. See also Ulrich Drepper's
417 * paper "How to Write Shared Libraries" for more information about relocation
418 * (http://people.redhat.com/drepper/dsohowto.pdf).
419 * Note: the contents of the .got section is only modified by the MIPS resolver.
420 */
421static void DRD_(suppress_relocation_conflicts)(const Addr a, const SizeT len)
422{
423   const DebugInfo* di;
424
425   if (trace_sectsuppr)
426      VG_(dmsg)("Evaluating range @ 0x%lx size %ld\n", a, len);
427
428   for (di = VG_(next_DebugInfo)(0); di; di = VG_(next_DebugInfo)(di)) {
429      Addr  avma;
430      SizeT size;
431
432      if (trace_sectsuppr)
433	 VG_(dmsg)("Examining %s / %s\n", VG_(DebugInfo_get_filename)(di),
434		   VG_(DebugInfo_get_soname)(di));
435
436      /*
437       * Suppress the race report on the libpthread global variable
438       * __pthread_multiple_threads. See also
439       * http://bugs.kde.org/show_bug.cgi?id=323905.
440       */
441      avma = VG_(DebugInfo_get_bss_avma)(di);
442      size = VG_(DebugInfo_get_bss_size)(di);
443      tl_assert((avma && size) || (avma == 0 && size == 0));
444      if (size > 0 &&
445          VG_(strcmp)(VG_(DebugInfo_get_soname)(di), "libpthread.so.0") == 0) {
446	 if (trace_sectsuppr)
447	    VG_(dmsg)("Suppressing .bss @ 0x%lx size %ld\n", avma, size);
448         tl_assert(VG_(DebugInfo_sect_kind)(NULL, 0, avma) == Vg_SectBSS);
449         DRD_(start_suppression)(avma, avma + size, ".bss");
450      }
451
452      avma = VG_(DebugInfo_get_plt_avma)(di);
453      size = VG_(DebugInfo_get_plt_size)(di);
454      tl_assert((avma && size) || (avma == 0 && size == 0));
455      if (size > 0) {
456	 if (trace_sectsuppr)
457	    VG_(dmsg)("Suppressing .plt @ 0x%lx size %ld\n", avma, size);
458         tl_assert(VG_(DebugInfo_sect_kind)(NULL, 0, avma) == Vg_SectPLT);
459         DRD_(start_suppression)(avma, avma + size, ".plt");
460      }
461
462      avma = VG_(DebugInfo_get_gotplt_avma)(di);
463      size = VG_(DebugInfo_get_gotplt_size)(di);
464      tl_assert((avma && size) || (avma == 0 && size == 0));
465      if (size > 0) {
466	 if (trace_sectsuppr)
467	    VG_(dmsg)("Suppressing .got.plt @ 0x%lx size %ld\n", avma, size);
468         tl_assert(VG_(DebugInfo_sect_kind)(NULL, 0, avma) == Vg_SectGOTPLT);
469         DRD_(start_suppression)(avma, avma + size, ".gotplt");
470      }
471
472      avma = VG_(DebugInfo_get_got_avma)(di);
473      size = VG_(DebugInfo_get_got_size)(di);
474      tl_assert((avma && size) || (avma == 0 && size == 0));
475      if (size > 0) {
476	 if (trace_sectsuppr)
477	    VG_(dmsg)("Suppressing .got @ 0x%lx size %ld\n", avma, size);
478         tl_assert(VG_(DebugInfo_sect_kind)(NULL, 0, avma) == Vg_SectGOT);
479         DRD_(start_suppression)(avma, avma + size, ".got");
480      }
481   }
482}
483
484static
485void drd_start_using_mem_w_perms(const Addr a, const SizeT len,
486                                 const Bool rr, const Bool ww, const Bool xx,
487                                 ULong di_handle)
488{
489   DRD_(thread_set_vg_running_tid)(VG_(get_running_tid)());
490
491   drd_start_using_mem(a, len, False);
492
493   DRD_(suppress_relocation_conflicts)(a, len);
494}
495
496/**
497 * Called by the core when the stack of a thread grows, to indicate that
498 * the addresses in range [ a, a + len [ may now be used by the client.
499 * Assumption: stacks grow downward.
500 */
501static __inline__
502void drd_start_using_mem_stack2(const DrdThreadId tid, const Addr a,
503                                const SizeT len)
504{
505   DRD_(thread_set_stack_min)(tid, a - VG_STACK_REDZONE_SZB);
506   drd_start_using_mem(a - VG_STACK_REDZONE_SZB, len + VG_STACK_REDZONE_SZB,
507                       True);
508}
509
510static __inline__
511void drd_start_using_mem_stack(const Addr a, const SizeT len)
512{
513   drd_start_using_mem_stack2(DRD_(thread_get_running_tid)(), a, len);
514}
515
516/**
517 * Called by the core when the stack of a thread shrinks, to indicate that
518 * the addresses [ a, a + len [ are no longer accessible for the client.
519 * Assumption: stacks grow downward.
520 */
521static __inline__
522void drd_stop_using_mem_stack2(const DrdThreadId tid, const Addr a,
523                               const SizeT len)
524{
525   DRD_(thread_set_stack_min)(tid, a + len - VG_STACK_REDZONE_SZB);
526   drd_stop_using_mem(a - VG_STACK_REDZONE_SZB, len + VG_STACK_REDZONE_SZB,
527                      True);
528}
529
530static __inline__
531void drd_stop_using_mem_stack(const Addr a, const SizeT len)
532{
533   drd_stop_using_mem_stack2(DRD_(thread_get_running_tid)(), a, len);
534}
535
536static
537Bool on_alt_stack(const Addr a)
538{
539   ThreadId vg_tid;
540   Addr alt_min;
541   SizeT alt_size;
542
543   vg_tid = VG_(get_running_tid)();
544   alt_min = VG_(thread_get_altstack_min)(vg_tid);
545   alt_size = VG_(thread_get_altstack_size)(vg_tid);
546   return (SizeT)(a - alt_min) < alt_size;
547}
548
549static
550void drd_start_using_mem_alt_stack(const Addr a, const SizeT len)
551{
552   if (!on_alt_stack(a))
553      drd_start_using_mem_stack(a, len);
554}
555
556static
557void drd_stop_using_mem_alt_stack(const Addr a, const SizeT len)
558{
559   if (!on_alt_stack(a))
560      drd_stop_using_mem_stack(a, len);
561}
562
563/**
564 * Callback function invoked by the Valgrind core before a signal is delivered.
565 */
566static
567void drd_pre_deliver_signal(const ThreadId vg_tid, const Int sigNo,
568                            const Bool alt_stack)
569{
570   DrdThreadId drd_tid;
571
572   drd_tid = DRD_(VgThreadIdToDrdThreadId)(vg_tid);
573   DRD_(thread_set_on_alt_stack)(drd_tid, alt_stack);
574   if (alt_stack)
575   {
576      /*
577       * As soon a signal handler has been invoked on the alternate stack,
578       * switch to stack memory handling functions that can handle the
579       * alternate stack.
580       */
581      VG_(track_new_mem_stack)(drd_start_using_mem_alt_stack);
582      VG_(track_die_mem_stack)(drd_stop_using_mem_alt_stack);
583   }
584}
585
586/**
587 * Callback function invoked by the Valgrind core after a signal is delivered,
588 * at least if the signal handler did not longjmp().
589 */
590static
591void drd_post_deliver_signal(const ThreadId vg_tid, const Int sigNo)
592{
593   DrdThreadId drd_tid;
594
595   drd_tid = DRD_(VgThreadIdToDrdThreadId)(vg_tid);
596   DRD_(thread_set_on_alt_stack)(drd_tid, False);
597   if (DRD_(thread_get_threads_on_alt_stack)() == 0)
598   {
599      VG_(track_new_mem_stack)(drd_start_using_mem_stack);
600      VG_(track_die_mem_stack)(drd_stop_using_mem_stack);
601   }
602}
603
604/**
605 * Callback function called by the Valgrind core before a stack area is
606 * being used by a signal handler.
607 *
608 * @param[in] a   Start of address range - VG_STACK_REDZONE_SZB.
609 * @param[in] len Address range length + VG_STACK_REDZONE_SZB.
610 * @param[in] tid Valgrind thread ID for whom the signal frame is being
611 *                constructed.
612 */
613static void drd_start_using_mem_stack_signal(const Addr a, const SizeT len,
614                                             ThreadId tid)
615{
616   DRD_(thread_set_vg_running_tid)(VG_(get_running_tid)());
617   drd_start_using_mem(a + VG_STACK_REDZONE_SZB, len - VG_STACK_REDZONE_SZB,
618                       True);
619}
620
621static void drd_stop_using_mem_stack_signal(Addr a, SizeT len)
622{
623   drd_stop_using_mem(a + VG_STACK_REDZONE_SZB, len - VG_STACK_REDZONE_SZB,
624                      True);
625}
626
627static
628void drd_pre_thread_create(const ThreadId creator, const ThreadId created)
629{
630   const DrdThreadId drd_creator = DRD_(VgThreadIdToDrdThreadId)(creator);
631   tl_assert(created != VG_INVALID_THREADID);
632   DRD_(thread_pre_create)(drd_creator, created);
633   if (DRD_(IsValidDrdThreadId)(drd_creator))
634   {
635      DRD_(thread_new_segment)(drd_creator);
636   }
637   if (DRD_(thread_get_trace_fork_join)())
638   {
639      DRD_(trace_msg)("drd_pre_thread_create creator = %d, created = %d",
640                      drd_creator, created);
641   }
642}
643
644/**
645 * Called by Valgrind's core before any loads or stores are performed on
646 * the context of thread "created".
647 */
648static
649void drd_post_thread_create(const ThreadId vg_created)
650{
651   DrdThreadId drd_created;
652   Addr stack_max;
653
654   tl_assert(vg_created != VG_INVALID_THREADID);
655
656   drd_created = DRD_(thread_post_create)(vg_created);
657
658   /* Set up red zone before the code in glibc's clone.S is run. */
659   stack_max = DRD_(thread_get_stack_max)(drd_created);
660   drd_start_using_mem_stack2(drd_created, stack_max, 0);
661
662   if (DRD_(thread_get_trace_fork_join)())
663   {
664      DRD_(trace_msg)("drd_post_thread_create created = %d", drd_created);
665   }
666   if (! DRD_(get_check_stack_accesses)())
667   {
668      DRD_(start_suppression)(DRD_(thread_get_stack_max)(drd_created)
669                              - DRD_(thread_get_stack_size)(drd_created),
670                              DRD_(thread_get_stack_max)(drd_created),
671                              "stack");
672   }
673}
674
675/* Called after a thread has performed its last memory access. */
676static void drd_thread_finished(ThreadId vg_tid)
677{
678   DrdThreadId drd_tid;
679
680   /*
681    * Ignore if invoked because thread creation failed. See e.g.
682    * coregrind/m_syswrap/syswrap-amd64-linux.c
683    */
684   if (VG_(get_running_tid)() != vg_tid)
685      return;
686
687   drd_tid = DRD_(VgThreadIdToDrdThreadId)(vg_tid);
688   tl_assert(drd_tid != DRD_INVALID_THREADID);
689   if (DRD_(thread_get_trace_fork_join)())
690   {
691      DRD_(trace_msg)("drd_thread_finished tid = %d%s", drd_tid,
692                      DRD_(thread_get_joinable)(drd_tid)
693                      ? "" : " (which is a detached thread)");
694   }
695   if (s_show_stack_usage && !VG_(clo_xml)) {
696      const SizeT stack_size = DRD_(thread_get_stack_size)(drd_tid);
697      const SizeT used_stack
698         = (DRD_(thread_get_stack_max)(drd_tid)
699            - DRD_(thread_get_stack_min_min)(drd_tid));
700      VG_(message)(Vg_UserMsg,
701                   "thread %d%s finished and used %ld bytes out of %ld"
702                   " on its stack. Margin: %ld bytes.\n",
703                   drd_tid,
704                   DRD_(thread_get_joinable)(drd_tid)
705                   ? "" : " (which is a detached thread)",
706                   used_stack, stack_size, stack_size - used_stack);
707
708   }
709   drd_stop_using_mem(DRD_(thread_get_stack_min)(drd_tid),
710                      DRD_(thread_get_stack_max)(drd_tid)
711                      - DRD_(thread_get_stack_min)(drd_tid),
712                      True);
713   DRD_(thread_set_record_loads)(drd_tid, False);
714   DRD_(thread_set_record_stores)(drd_tid, False);
715   DRD_(thread_finished)(drd_tid);
716}
717
718/*
719 * Called immediately after fork for the child process only. 'tid' is the
720 * only surviving thread in the child process. Cleans up thread state.
721 * See also http://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_atfork.html for a detailed discussion of using fork() in combination with mutexes.
722 */
723static
724void drd__atfork_child(ThreadId tid)
725{
726   DRD_(drd_thread_atfork_child)(tid);
727}
728
729
730//
731// Implementation of the tool interface.
732//
733
734static void DRD_(post_clo_init)(void)
735{
736#if defined(VGO_linux) || defined(VGO_darwin)
737   /* fine */
738#else
739   VG_(printf)("\nWARNING: DRD has not yet been tested on this operating system.\n\n");
740#  endif
741
742   if (s_var_info)
743   {
744      VG_(needs_var_info)();
745   }
746}
747
748static void drd_start_client_code(const ThreadId tid, const ULong bbs_done)
749{
750   tl_assert(tid == VG_(get_running_tid)());
751   DRD_(thread_set_vg_running_tid)(tid);
752}
753
754static void DRD_(fini)(Int exitcode)
755{
756   // thread_print_all();
757   if (VG_(clo_verbosity) == 1 && !VG_(clo_xml)) {
758      VG_(message)(Vg_UserMsg, "For counts of detected and suppressed errors, "
759                   "rerun with: -v\n");
760   }
761
762   if ((VG_(clo_stats) || s_print_stats) && !VG_(clo_xml))
763   {
764      ULong pu = DRD_(thread_get_update_conflict_set_count)();
765      ULong pu_seg_cr = DRD_(thread_get_update_conflict_set_new_sg_count)();
766      ULong pu_mtx_cv = DRD_(thread_get_update_conflict_set_sync_count)();
767      ULong pu_join   = DRD_(thread_get_update_conflict_set_join_count)();
768
769      VG_(message)(Vg_UserMsg,
770                   "   thread: %lld context switches.\n",
771                   DRD_(thread_get_context_switch_count)());
772      VG_(message)(Vg_UserMsg,
773                   "confl set: %lld full updates and %lld partial updates;\n",
774                   DRD_(thread_get_compute_conflict_set_count)(),
775                   pu);
776      VG_(message)(Vg_UserMsg,
777                   "           %lld partial updates during segment creation,\n",
778                   pu_seg_cr);
779      VG_(message)(Vg_UserMsg,
780                   "           %lld because of mutex/sema/cond.var. operations,\n",
781                   pu_mtx_cv);
782      VG_(message)(Vg_UserMsg,
783                   "           %lld because of barrier/rwlock operations and\n",
784		   pu - pu_seg_cr - pu_mtx_cv - pu_join);
785      VG_(message)(Vg_UserMsg,
786                   "           %lld partial updates because of thread join"
787                   " operations.\n",
788                   pu_join);
789      VG_(message)(Vg_UserMsg,
790                   " segments: created %lld segments, max %lld alive,\n",
791                   DRD_(sg_get_segments_created_count)(),
792                   DRD_(sg_get_max_segments_alive_count)());
793      VG_(message)(Vg_UserMsg,
794                   "           %lld discard points and %lld merges.\n",
795                   DRD_(thread_get_discard_ordered_segments_count)(),
796                   DRD_(sg_get_segment_merge_count)());
797      VG_(message)(Vg_UserMsg,
798                   "segmnt cr: %lld mutex, %lld rwlock, %lld semaphore and"
799                   " %lld barrier.\n",
800                   DRD_(get_mutex_segment_creation_count)(),
801                   DRD_(get_rwlock_segment_creation_count)(),
802                   DRD_(get_semaphore_segment_creation_count)(),
803                   DRD_(get_barrier_segment_creation_count)());
804      VG_(message)(Vg_UserMsg,
805                   "  bitmaps: %lld level one"
806                   " and %lld level two bitmaps were allocated.\n",
807                   DRD_(bm_get_bitmap_creation_count)(),
808                   DRD_(bm_get_bitmap2_creation_count)());
809      VG_(message)(Vg_UserMsg,
810                   "    mutex: %lld non-recursive lock/unlock events.\n",
811                   DRD_(get_mutex_lock_count)());
812      DRD_(print_malloc_stats)();
813   }
814
815   DRD_(bm_module_cleanup)();
816}
817
818static
819void drd_pre_clo_init(void)
820{
821   // Basic tool stuff.
822   VG_(details_name)            ("drd");
823   VG_(details_version)         (NULL);
824   VG_(details_description)     ("a thread error detector");
825   VG_(details_copyright_author)("Copyright (C) 2006-2013, and GNU GPL'd,"
826                                 " by Bart Van Assche.");
827   VG_(details_bug_reports_to)  (VG_BUGS_TO);
828
829   VG_(basic_tool_funcs)        (DRD_(post_clo_init),
830                                 DRD_(instrument),
831                                 DRD_(fini));
832
833   // Command line stuff.
834   VG_(needs_command_line_options)(DRD_(process_cmd_line_option),
835                                   DRD_(print_usage),
836                                   DRD_(print_debug_usage));
837   VG_(needs_xml_output)          ();
838
839   // Error handling.
840   DRD_(register_error_handlers)();
841
842   // Core event tracking.
843   VG_(track_pre_mem_read)         (drd_pre_mem_read);
844   VG_(track_pre_mem_read_asciiz)  (drd_pre_mem_read_asciiz);
845   VG_(track_post_mem_write)       (drd_post_mem_write);
846   VG_(track_new_mem_brk)          (drd_start_using_mem_w_tid);
847   VG_(track_new_mem_mmap)         (drd_start_using_mem_w_perms);
848   VG_(track_new_mem_stack)        (drd_start_using_mem_stack);
849   VG_(track_new_mem_stack_signal) (drd_start_using_mem_stack_signal);
850   VG_(track_new_mem_startup)      (drd_start_using_mem_w_perms);
851   VG_(track_die_mem_brk)          (drd_stop_using_nonstack_mem);
852   VG_(track_die_mem_munmap)       (drd_stop_using_nonstack_mem);
853   VG_(track_die_mem_stack)        (drd_stop_using_mem_stack);
854   VG_(track_die_mem_stack_signal) (drd_stop_using_mem_stack_signal);
855   VG_(track_pre_deliver_signal)   (drd_pre_deliver_signal);
856   VG_(track_post_deliver_signal)  (drd_post_deliver_signal);
857   VG_(track_start_client_code)    (drd_start_client_code);
858   VG_(track_pre_thread_ll_create) (drd_pre_thread_create);
859   VG_(track_pre_thread_first_insn)(drd_post_thread_create);
860   VG_(track_pre_thread_ll_exit)   (drd_thread_finished);
861   VG_(atfork)                     (NULL/*pre*/, NULL/*parent*/,
862				    drd__atfork_child/*child*/);
863
864   // Other stuff.
865   DRD_(register_malloc_wrappers)(drd_start_using_mem_w_ecu,
866                                  drd_stop_using_nonstack_mem);
867
868   DRD_(bm_module_init)();
869
870   DRD_(clientreq_init)();
871
872   DRD_(suppression_init)();
873
874   DRD_(clientobj_init)();
875
876   DRD_(thread_init)();
877
878   {
879      HChar* const smi = VG_(getenv)("DRD_SEGMENT_MERGING_INTERVAL");
880      if (smi)
881         DRD_(thread_set_segment_merge_interval)(VG_(strtoll10)(smi, NULL));
882   }
883}
884
885
886VG_DETERMINE_INTERFACE_VERSION(drd_pre_clo_init)
887