blob: 62eb0f35a8917387a019c8f066493ce04be99352 [file] [log] [blame]
/*
This file is part of drd, a data race detector.
Copyright (C) 2006-2008 Bart Van Assche
bart.vanassche@gmail.com
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307, USA.
The GNU General Public License is contained in the file COPYING.
*/
#include "drd_error.h"
#include "drd_segment.h"
#include "drd_suppression.h"
#include "drd_thread.h"
#include "pub_tool_basics.h" // Addr, SizeT
#include "pub_tool_errormgr.h" // VG_(unique_error)()
#include "pub_tool_libcassert.h" // tl_assert()
#include "pub_tool_libcbase.h" // VG_(strlen)()
#include "pub_tool_libcprint.h" // VG_(printf)()
#include "pub_tool_machine.h"
#include "pub_tool_mallocfree.h" // VG_(malloc)(), VG_(free)()
#include "pub_tool_options.h" // VG_(clo_backtrace_size)
#include "pub_tool_threadstate.h" // VG_(get_pthread_id)()
// Local functions.
static void thread_append_segment(const DrdThreadId tid,
Segment* const sg);
static void thread_discard_segment(const DrdThreadId tid, Segment* const sg);
static void thread_update_danger_set(const DrdThreadId tid);
// Local variables.
static ULong s_context_switch_count;
static ULong s_discard_ordered_segments_count;
static ULong s_update_danger_set_count;
static ULong s_danger_set_bitmap_creation_count;
static ULong s_danger_set_bitmap2_creation_count;
static ThreadId s_vg_running_tid = VG_INVALID_THREADID;
DrdThreadId s_drd_running_tid = DRD_INVALID_THREADID;
ThreadInfo s_threadinfo[DRD_N_THREADS];
struct bitmap* s_danger_set;
static Bool s_trace_context_switches = False;
static Bool s_trace_danger_set = False;
static Bool s_segment_merging = True;
// Function definitions.
void thread_trace_context_switches(const Bool t)
{
s_trace_context_switches = t;
}
void thread_trace_danger_set(const Bool t)
{
s_trace_danger_set = t;
}
void thread_set_segment_merging(const Bool m)
{
s_segment_merging = m;
}
__inline__ Bool IsValidDrdThreadId(const DrdThreadId tid)
{
return (0 <= tid && tid < DRD_N_THREADS && tid != DRD_INVALID_THREADID
&& ! (s_threadinfo[tid].vg_thread_exists == False
&& s_threadinfo[tid].posix_thread_exists == False
&& s_threadinfo[tid].detached_posix_thread == False));
}
/**
* Convert Valgrind's ThreadId into a DrdThreadId. Report failure if
* Valgrind's ThreadId does not yet exist.
**/
DrdThreadId VgThreadIdToDrdThreadId(const ThreadId tid)
{
int i;
if (tid == VG_INVALID_THREADID)
return DRD_INVALID_THREADID;
for (i = 1; i < DRD_N_THREADS; i++)
{
if (s_threadinfo[i].vg_thread_exists == True
&& s_threadinfo[i].vg_threadid == tid)
{
return i;
}
}
return DRD_INVALID_THREADID;
}
static
DrdThreadId VgThreadIdToNewDrdThreadId(const ThreadId tid)
{
int i;
tl_assert(VgThreadIdToDrdThreadId(tid) == DRD_INVALID_THREADID);
for (i = 1; i < DRD_N_THREADS; i++)
{
if (s_threadinfo[i].vg_thread_exists == False
&& s_threadinfo[i].posix_thread_exists == False
&& s_threadinfo[i].detached_posix_thread == False)
{
s_threadinfo[i].vg_thread_exists = True;
s_threadinfo[i].vg_threadid = tid;
s_threadinfo[i].pt_threadid = INVALID_POSIX_THREADID;
s_threadinfo[i].stack_min = 0;
s_threadinfo[i].stack_startup = 0;
s_threadinfo[i].stack_max = 0;
s_threadinfo[i].is_recording = True;
s_threadinfo[i].synchr_nesting = 0;
if (s_threadinfo[i].first != 0)
VG_(printf)("drd thread id = %d\n", i);
tl_assert(s_threadinfo[i].first == 0);
tl_assert(s_threadinfo[i].last == 0);
return i;
}
}
tl_assert(False);
return DRD_INVALID_THREADID;
}
DrdThreadId PtThreadIdToDrdThreadId(const PThreadId tid)
{
int i;
tl_assert(tid != INVALID_POSIX_THREADID);
for (i = 1; i < DRD_N_THREADS; i++)
{
if (s_threadinfo[i].posix_thread_exists
&& s_threadinfo[i].pt_threadid == tid)
{
return i;
}
}
return DRD_INVALID_THREADID;
}
ThreadId DrdThreadIdToVgThreadId(const DrdThreadId tid)
{
tl_assert(0 <= tid && tid < DRD_N_THREADS && tid != DRD_INVALID_THREADID);
return (s_threadinfo[tid].vg_thread_exists
? s_threadinfo[tid].vg_threadid
: VG_INVALID_THREADID);
}
/** Sanity check of the doubly linked list of segments referenced by a
* ThreadInfo struct.
* @return True if sane, False if not.
*/
static Bool sane_ThreadInfo(const ThreadInfo* const ti)
{
Segment* p;
for (p = ti->first; p; p = p->next) {
if (p->next && p->next->prev != p)
return False;
if (p->next == 0 && p != ti->last)
return False;
}
for (p = ti->last; p; p = p->prev) {
if (p->prev && p->prev->next != p)
return False;
if (p->prev == 0 && p != ti->first)
return False;
}
return True;
}
DrdThreadId thread_pre_create(const DrdThreadId creator,
const ThreadId vg_created)
{
DrdThreadId created;
tl_assert(VgThreadIdToDrdThreadId(vg_created) == DRD_INVALID_THREADID);
created = VgThreadIdToNewDrdThreadId(vg_created);
tl_assert(0 <= created && created < DRD_N_THREADS
&& created != DRD_INVALID_THREADID);
tl_assert(s_threadinfo[created].first == 0);
tl_assert(s_threadinfo[created].last == 0);
thread_append_segment(created, sg_new(creator, created));
return created;
}
/** Allocate the first segment for a thread. Call this just after
* pthread_create().
*/
DrdThreadId thread_post_create(const ThreadId vg_created)
{
const DrdThreadId created = VgThreadIdToDrdThreadId(vg_created);
tl_assert(0 <= created && created < DRD_N_THREADS
&& created != DRD_INVALID_THREADID);
s_threadinfo[created].stack_max = VG_(thread_get_stack_max)(vg_created);
s_threadinfo[created].stack_startup = s_threadinfo[created].stack_max;
s_threadinfo[created].stack_min = s_threadinfo[created].stack_max;
tl_assert(s_threadinfo[created].stack_max != 0);
return created;
}
/* NPTL hack: NPTL allocates the 'struct pthread' on top of the stack, */
/* and accesses this data structure from multiple threads without locking. */
/* Any conflicting accesses in the range stack_startup..stack_max will be */
/* ignored. */
void thread_set_stack_startup(const DrdThreadId tid, const Addr stack_startup)
{
tl_assert(0 <= tid && tid < DRD_N_THREADS && tid != DRD_INVALID_THREADID);
tl_assert(s_threadinfo[tid].stack_min <= stack_startup);
tl_assert(stack_startup <= s_threadinfo[tid].stack_max);
s_threadinfo[tid].stack_startup = stack_startup;
}
Addr thread_get_stack_min(const DrdThreadId tid)
{
tl_assert(0 <= tid && tid < DRD_N_THREADS
&& tid != DRD_INVALID_THREADID);
return s_threadinfo[tid].stack_min;
}
Addr thread_get_stack_max(const DrdThreadId tid)
{
tl_assert(0 <= tid && tid < DRD_N_THREADS
&& tid != DRD_INVALID_THREADID);
return s_threadinfo[tid].stack_max;
}
/** Clean up thread-specific data structures. Call this just after
* pthread_join().
*/
void thread_delete(const DrdThreadId tid)
{
Segment* sg;
Segment* sg_prev;
tl_assert(0 <= tid && tid < DRD_N_THREADS
&& tid != DRD_INVALID_THREADID);
tl_assert(s_threadinfo[tid].synchr_nesting == 0);
for (sg = s_threadinfo[tid].last; sg; sg = sg_prev)
{
sg_prev = sg->prev;
sg->prev = 0;
sg->next = 0;
sg_put(sg);
}
s_threadinfo[tid].vg_thread_exists = False;
s_threadinfo[tid].posix_thread_exists = False;
tl_assert(s_threadinfo[tid].detached_posix_thread == False);
s_threadinfo[tid].first = 0;
s_threadinfo[tid].last = 0;
}
/* Called after a thread performed its last memory access and before */
/* thread_delete() is called. Note: thread_delete() is only called for */
/* joinable threads, not for detached threads. */
void thread_finished(const DrdThreadId tid)
{
tl_assert(0 <= tid && tid < DRD_N_THREADS
&& tid != DRD_INVALID_THREADID);
s_threadinfo[tid].vg_thread_exists = False;
if (s_threadinfo[tid].detached_posix_thread)
{
/* Once a detached thread has finished, its stack is deallocated and */
/* should no longer be taken into account when computing the danger set*/
s_threadinfo[tid].stack_min = s_threadinfo[tid].stack_max;
/* For a detached thread, calling pthread_exit() invalidates the */
/* POSIX thread ID associated with the detached thread. For joinable */
/* POSIX threads however, the POSIX thread ID remains live after the */
/* pthread_exit() call until pthread_join() is called. */
s_threadinfo[tid].posix_thread_exists = False;
}
}
void thread_set_pthreadid(const DrdThreadId tid, const PThreadId ptid)
{
tl_assert(0 <= tid && tid < DRD_N_THREADS
&& tid != DRD_INVALID_THREADID);
tl_assert(s_threadinfo[tid].pt_threadid == INVALID_POSIX_THREADID);
tl_assert(ptid != INVALID_POSIX_THREADID);
s_threadinfo[tid].posix_thread_exists = True;
s_threadinfo[tid].pt_threadid = ptid;
}
Bool thread_get_joinable(const DrdThreadId tid)
{
tl_assert(0 <= tid && tid < DRD_N_THREADS
&& tid != DRD_INVALID_THREADID);
return ! s_threadinfo[tid].detached_posix_thread;
}
void thread_set_joinable(const DrdThreadId tid, const Bool joinable)
{
tl_assert(0 <= tid && tid < DRD_N_THREADS
&& tid != DRD_INVALID_THREADID);
tl_assert(!! joinable == joinable);
tl_assert(s_threadinfo[tid].pt_threadid != INVALID_POSIX_THREADID);
#if 0
VG_(message)(Vg_DebugMsg,
"thread_set_joinable(%d/%d, %s)",
tid,
s_threadinfo[tid].vg_threadid,
joinable ? "joinable" : "detached");
#endif
s_threadinfo[tid].detached_posix_thread = ! joinable;
}
void thread_set_vg_running_tid(const ThreadId vg_tid)
{
tl_assert(vg_tid != VG_INVALID_THREADID);
if (vg_tid != s_vg_running_tid)
{
thread_set_running_tid(vg_tid, VgThreadIdToDrdThreadId(vg_tid));
}
tl_assert(s_vg_running_tid != VG_INVALID_THREADID);
tl_assert(s_drd_running_tid != DRD_INVALID_THREADID);
}
void thread_set_running_tid(const ThreadId vg_tid, const DrdThreadId drd_tid)
{
tl_assert(vg_tid != VG_INVALID_THREADID);
tl_assert(drd_tid != DRD_INVALID_THREADID);
if (vg_tid != s_vg_running_tid)
{
if (s_trace_context_switches
&& s_drd_running_tid != DRD_INVALID_THREADID)
{
VG_(message)(Vg_DebugMsg,
"Context switch from thread %d/%d to thread %d/%d;"
" segments: %llu",
s_vg_running_tid, s_drd_running_tid,
DrdThreadIdToVgThreadId(drd_tid), drd_tid,
sg_get_alive_segments_count());
}
s_vg_running_tid = vg_tid;
s_drd_running_tid = drd_tid;
thread_update_danger_set(drd_tid);
s_context_switch_count++;
}
tl_assert(s_vg_running_tid != VG_INVALID_THREADID);
tl_assert(s_drd_running_tid != DRD_INVALID_THREADID);
}
int thread_enter_synchr(const DrdThreadId tid)
{
tl_assert(IsValidDrdThreadId(tid));
return s_threadinfo[tid].synchr_nesting++;
}
int thread_leave_synchr(const DrdThreadId tid)
{
tl_assert(IsValidDrdThreadId(tid));
tl_assert(s_threadinfo[tid].synchr_nesting >= 1);
return --s_threadinfo[tid].synchr_nesting;
}
int thread_get_synchr_nesting_count(const DrdThreadId tid)
{
tl_assert(IsValidDrdThreadId(tid));
return s_threadinfo[tid].synchr_nesting;
}
/** Append a new segment at the end of the segment list. */
static void thread_append_segment(const DrdThreadId tid, Segment* const sg)
{
tl_assert(0 <= tid && tid < DRD_N_THREADS
&& tid != DRD_INVALID_THREADID);
tl_assert(sane_ThreadInfo(&s_threadinfo[tid]));
sg->prev = s_threadinfo[tid].last;
sg->next = 0;
if (s_threadinfo[tid].last)
s_threadinfo[tid].last->next = sg;
s_threadinfo[tid].last = sg;
if (s_threadinfo[tid].first == 0)
s_threadinfo[tid].first = sg;
tl_assert(sane_ThreadInfo(&s_threadinfo[tid]));
}
/** Remove a segment from the segment list of thread threadid, and free the
* associated memory.
*/
static void thread_discard_segment(const DrdThreadId tid, Segment* const sg)
{
tl_assert(0 <= tid && tid < DRD_N_THREADS
&& tid != DRD_INVALID_THREADID);
tl_assert(sane_ThreadInfo(&s_threadinfo[tid]));
if (sg->prev)
sg->prev->next = sg->next;
if (sg->next)
sg->next->prev = sg->prev;
if (sg == s_threadinfo[tid].first)
s_threadinfo[tid].first = sg->next;
if (sg == s_threadinfo[tid].last)
s_threadinfo[tid].last = sg->prev;
sg_put(sg);
tl_assert(sane_ThreadInfo(&s_threadinfo[tid]));
}
VectorClock* thread_get_vc(const DrdThreadId tid)
{
tl_assert(0 <= tid && tid < DRD_N_THREADS && tid != DRD_INVALID_THREADID);
tl_assert(s_threadinfo[tid].last);
return &s_threadinfo[tid].last->vc;
}
/** Return the latest segment of thread 'tid' and increment its reference
* count.
*/
void thread_get_latest_segment(Segment** sg, const DrdThreadId tid)
{
tl_assert(sg);
tl_assert(0 <= tid && tid < DRD_N_THREADS && tid != DRD_INVALID_THREADID);
tl_assert(s_threadinfo[tid].last);
sg_put(*sg);
*sg = sg_get(s_threadinfo[tid].last);
}
/**
* Compute the minimum of all latest vector clocks of all threads
* (Michiel Ronsse calls this "clock snooping" in his papers about DIOTA).
* @param vc pointer to a vectorclock, holds result upon return.
*/
static void thread_compute_minimum_vc(VectorClock* vc)
{
unsigned i;
Bool first;
Segment* latest_sg;
first = True;
for (i = 0; i < sizeof(s_threadinfo) / sizeof(s_threadinfo[0]); i++)
{
latest_sg = s_threadinfo[i].last;
if (latest_sg)
{
if (first)
vc_assign(vc, &latest_sg->vc);
else
vc_min(vc, &latest_sg->vc);
first = False;
}
}
}
static void thread_compute_maximum_vc(VectorClock* vc)
{
unsigned i;
Bool first;
Segment* latest_sg;
first = True;
for (i = 0; i < sizeof(s_threadinfo) / sizeof(s_threadinfo[0]); i++)
{
latest_sg = s_threadinfo[i].last;
if (latest_sg)
{
if (first)
vc_assign(vc, &latest_sg->vc);
else
vc_combine(vc, &latest_sg->vc);
first = False;
}
}
}
/**
* Discard all segments that have a defined order against the latest vector
* clock of every thread -- these segments can no longer be involved in a
* data race.
*/
static void thread_discard_ordered_segments(void)
{
unsigned i;
VectorClock thread_vc_min;
s_discard_ordered_segments_count++;
vc_init(&thread_vc_min, 0, 0);
thread_compute_minimum_vc(&thread_vc_min);
if (sg_get_trace())
{
char msg[256];
VectorClock thread_vc_max;
vc_init(&thread_vc_max, 0, 0);
thread_compute_maximum_vc(&thread_vc_max);
VG_(snprintf)(msg, sizeof(msg),
"Discarding ordered segments -- min vc is ");
vc_snprint(msg + VG_(strlen)(msg), sizeof(msg) - VG_(strlen)(msg),
&thread_vc_min);
VG_(snprintf)(msg + VG_(strlen)(msg), sizeof(msg) - VG_(strlen)(msg),
", max vc is ");
vc_snprint(msg + VG_(strlen)(msg), sizeof(msg) - VG_(strlen)(msg),
&thread_vc_max);
VG_(message)(Vg_UserMsg, "%s", msg);
vc_cleanup(&thread_vc_max);
}
for (i = 0; i < sizeof(s_threadinfo) / sizeof(s_threadinfo[0]); i++)
{
Segment* sg;
Segment* sg_next;
for (sg = s_threadinfo[i].first;
sg && (sg_next = sg->next) && vc_lte(&sg->vc, &thread_vc_min);
sg = sg_next)
{
thread_discard_segment(i, sg);
}
}
vc_cleanup(&thread_vc_min);
}
/** Merge all segments that may be merged without triggering false positives
* or discarding real data races. For the theoretical background of segment
* merging, see also the following paper:
* Mark Christiaens, Michiel Ronsse and Koen De Bosschere.
* Bounding the number of segment histories during data race detection.
* Parallel Computing archive, Volume 28, Issue 9, pp 1221-1238,
* September 2002.
*/
static void thread_merge_segments(void)
{
unsigned i;
for (i = 0; i < sizeof(s_threadinfo) / sizeof(s_threadinfo[0]); i++)
{
Segment* sg;
tl_assert(sane_ThreadInfo(&s_threadinfo[i]));
for (sg = s_threadinfo[i].first; sg; sg = sg->next)
{
if (sg_get_refcnt(sg) == 1
&& sg->next
&& sg_get_refcnt(sg->next) == 1
&& sg->next->next)
{
/* Merge sg and sg->next into sg. */
sg_merge(sg, sg->next);
thread_discard_segment(i, sg->next);
}
}
tl_assert(sane_ThreadInfo(&s_threadinfo[i]));
}
}
/** Create a new segment for the specified thread, and discard any segments
* that cannot cause races anymore.
*/
void thread_new_segment(const DrdThreadId tid)
{
tl_assert(0 <= tid && tid < DRD_N_THREADS && tid != DRD_INVALID_THREADID);
thread_append_segment(tid, sg_new(tid, tid));
thread_discard_ordered_segments();
if (s_segment_merging)
thread_merge_segments();
if (tid == s_drd_running_tid)
{
/* Every change in the vector clock of the current thread may cause */
/* segments that were previously ordered to this thread to become */
/* unordered. Hence, recalculate the danger set if the vector clock */
/* of the current thread is updated. */
thread_update_danger_set(tid);
}
}
/** Call this function after thread 'joiner' joined thread 'joinee'. */
void thread_combine_vc(DrdThreadId joiner, DrdThreadId joinee)
{
tl_assert(joiner != joinee);
tl_assert(0 <= joiner && joiner < DRD_N_THREADS
&& joiner != DRD_INVALID_THREADID);
tl_assert(0 <= joinee && joinee < DRD_N_THREADS
&& joinee != DRD_INVALID_THREADID);
tl_assert(s_threadinfo[joiner].last);
tl_assert(s_threadinfo[joinee].last);
vc_combine(&s_threadinfo[joiner].last->vc, &s_threadinfo[joinee].last->vc);
thread_discard_ordered_segments();
if (joiner == s_drd_running_tid)
{
thread_update_danger_set(joiner);
}
}
/** Call this function after thread 'tid' had to wait because of thread
* synchronization until the memory accesses in the segment with vector clock
* 'vc' finished.
*/
void thread_combine_vc2(DrdThreadId tid, const VectorClock* const vc)
{
tl_assert(0 <= tid && tid < DRD_N_THREADS && tid != DRD_INVALID_THREADID);
tl_assert(s_threadinfo[tid].last);
tl_assert(vc);
vc_combine(&s_threadinfo[tid].last->vc, vc);
thread_discard_ordered_segments();
}
/** Call this function whenever a thread is no longer using the memory
* [ a1, a2 [, e.g. because of a call to free() or a stack pointer
* increase.
*/
void thread_stop_using_mem(const Addr a1, const Addr a2)
{
DrdThreadId other_user;
unsigned i;
/* For all threads, mark the range [ a1, a2 [ as no longer in use. */
other_user = DRD_INVALID_THREADID;
for (i = 0; i < sizeof(s_threadinfo) / sizeof(s_threadinfo[0]); i++)
{
Segment* p;
for (p = s_threadinfo[i].first; p; p = p->next)
{
if (other_user == DRD_INVALID_THREADID
&& i != s_drd_running_tid
&& bm_has_any_access(p->bm, a1, a2))
{
other_user = i;
}
bm_clear(p->bm, a1, a2);
}
}
/* If any other thread had accessed memory in [ a1, a2 [, update the */
/* danger set. */
if (other_user != DRD_INVALID_THREADID
&& bm_has_any_access(s_danger_set, a1, a2))
{
thread_update_danger_set(thread_get_running_tid());
}
}
void thread_start_recording(const DrdThreadId tid)
{
tl_assert(0 <= tid && tid < DRD_N_THREADS && tid != DRD_INVALID_THREADID);
tl_assert(! s_threadinfo[tid].is_recording);
s_threadinfo[tid].is_recording = True;
}
void thread_stop_recording(const DrdThreadId tid)
{
tl_assert(0 <= tid && tid < DRD_N_THREADS && tid != DRD_INVALID_THREADID);
tl_assert(s_threadinfo[tid].is_recording);
s_threadinfo[tid].is_recording = False;
}
void thread_print_all(void)
{
unsigned i;
Segment* p;
for (i = 0; i < sizeof(s_threadinfo) / sizeof(s_threadinfo[0]); i++)
{
if (s_threadinfo[i].first)
{
VG_(printf)("**************\n"
"* thread %3d (%d/%d/%d/0x%lx/%d) *\n"
"**************\n",
i,
s_threadinfo[i].vg_thread_exists,
s_threadinfo[i].vg_threadid,
s_threadinfo[i].posix_thread_exists,
s_threadinfo[i].pt_threadid,
s_threadinfo[i].detached_posix_thread);
for (p = s_threadinfo[i].first; p; p = p->next)
{
sg_print(p);
}
}
}
}
static void show_call_stack(const DrdThreadId tid,
const Char* const msg,
ExeContext* const callstack)
{
const ThreadId vg_tid = DrdThreadIdToVgThreadId(tid);
VG_(message)(Vg_UserMsg, "%s (thread %d/%d)", msg, vg_tid, tid);
if (vg_tid != VG_INVALID_THREADID)
{
if (callstack)
{
VG_(pp_ExeContext)(callstack);
}
else
{
VG_(get_and_pp_StackTrace)(vg_tid, VG_(clo_backtrace_size));
}
}
else
{
VG_(message)(Vg_UserMsg,
" (thread finished, call stack no longer available)");
}
}
static void
thread_report_conflicting_segments_segment(const DrdThreadId tid,
const Addr addr,
const SizeT size,
const BmAccessTypeT access_type,
const Segment* const p)
{
unsigned i;
tl_assert(0 <= tid && tid < DRD_N_THREADS
&& tid != DRD_INVALID_THREADID);
tl_assert(p);
for (i = 0; i < sizeof(s_threadinfo) / sizeof(s_threadinfo[0]); i++)
{
if (i != tid)
{
Segment* q;
for (q = s_threadinfo[i].last; q; q = q->prev)
{
// Since q iterates over the segments of thread i in order of
// decreasing vector clocks, if q->vc <= p->vc, then
// q->next->vc <= p->vc will also hold. Hence, break out of the
// loop once this condition is met.
if (vc_lte(&q->vc, &p->vc))
break;
if (! vc_lte(&p->vc, &q->vc))
{
if (bm_has_conflict_with(q->bm, addr, addr + size, access_type))
{
tl_assert(q->stacktrace);
show_call_stack(i, "Other segment start",
q->stacktrace);
show_call_stack(i, "Other segment end",
q->next ? q->next->stacktrace : 0);
}
}
}
}
}
}
void thread_report_conflicting_segments(const DrdThreadId tid,
const Addr addr,
const SizeT size,
const BmAccessTypeT access_type)
{
Segment* p;
tl_assert(0 <= tid && tid < DRD_N_THREADS
&& tid != DRD_INVALID_THREADID);
for (p = s_threadinfo[tid].first; p; p = p->next)
{
if (bm_has(p->bm, addr, addr + size, access_type))
{
thread_report_conflicting_segments_segment(tid, addr, size,
access_type, p);
}
}
}
/** Compute a bitmap that represents the union of all memory accesses of all
* segments that are unordered to the current segment of the thread tid.
*/
static void thread_update_danger_set(const DrdThreadId tid)
{
Segment* p;
tl_assert(0 <= tid && tid < DRD_N_THREADS && tid != DRD_INVALID_THREADID);
tl_assert(tid == s_drd_running_tid);
s_update_danger_set_count++;
s_danger_set_bitmap_creation_count -= bm_get_bitmap_creation_count();
s_danger_set_bitmap2_creation_count -= bm_get_bitmap2_creation_count();
if (s_danger_set)
{
bm_delete(s_danger_set);
}
s_danger_set = bm_new();
if (s_trace_danger_set)
{
char msg[256];
VG_(snprintf)(msg, sizeof(msg),
"computing danger set for thread %d/%d with vc ",
DrdThreadIdToVgThreadId(tid), tid);
vc_snprint(msg + VG_(strlen)(msg),
sizeof(msg) - VG_(strlen)(msg),
&s_threadinfo[tid].last->vc);
VG_(message)(Vg_UserMsg, "%s", msg);
}
p = s_threadinfo[tid].last;
{
unsigned j;
if (s_trace_danger_set)
{
char msg[256];
VG_(snprintf)(msg, sizeof(msg),
"danger set: thread [%d] at vc ",
tid);
vc_snprint(msg + VG_(strlen)(msg),
sizeof(msg) - VG_(strlen)(msg),
&p->vc);
VG_(message)(Vg_UserMsg, "%s", msg);
}
for (j = 0; j < sizeof(s_threadinfo) / sizeof(s_threadinfo[0]); j++)
{
if (IsValidDrdThreadId(j))
{
const Segment* q;
for (q = s_threadinfo[j].last; q; q = q->prev)
if (j != tid && q != 0
&& ! vc_lte(&q->vc, &p->vc) && ! vc_lte(&p->vc, &q->vc))
{
if (s_trace_danger_set)
{
char msg[256];
VG_(snprintf)(msg, sizeof(msg),
"danger set: [%d] merging segment ", j);
vc_snprint(msg + VG_(strlen)(msg),
sizeof(msg) - VG_(strlen)(msg),
&q->vc);
VG_(message)(Vg_UserMsg, "%s", msg);
}
bm_merge2(s_danger_set, q->bm);
}
else
{
if (s_trace_danger_set)
{
char msg[256];
VG_(snprintf)(msg, sizeof(msg),
"danger set: [%d] ignoring segment ", j);
vc_snprint(msg + VG_(strlen)(msg),
sizeof(msg) - VG_(strlen)(msg),
&q->vc);
VG_(message)(Vg_UserMsg, "%s", msg);
}
}
}
}
for (j = 0; j < sizeof(s_threadinfo) / sizeof(s_threadinfo[0]); j++)
{
if (IsValidDrdThreadId(j))
{
// NPTL hack: don't report data races on sizeof(struct pthread)
// bytes at the top of the stack, since the NPTL functions access
// this data without locking.
if (s_threadinfo[j].stack_min != 0)
{
tl_assert(s_threadinfo[j].stack_startup != 0);
if (s_threadinfo[j].stack_min < s_threadinfo[j].stack_startup)
{
bm_clear(s_danger_set,
s_threadinfo[j].stack_min,
s_threadinfo[j].stack_startup);
}
}
}
}
}
s_danger_set_bitmap_creation_count += bm_get_bitmap_creation_count();
s_danger_set_bitmap2_creation_count += bm_get_bitmap2_creation_count();
if (0 && s_trace_danger_set)
{
VG_(message)(Vg_UserMsg, "[%d] new danger set:", tid);
bm_print(s_danger_set);
VG_(message)(Vg_UserMsg, "[%d] end of new danger set.", tid);
}
}
ULong thread_get_context_switch_count(void)
{
return s_context_switch_count;
}
ULong thread_get_discard_ordered_segments_count(void)
{
return s_discard_ordered_segments_count;
}
ULong thread_get_update_danger_set_count(void)
{
return s_update_danger_set_count;
}
ULong thread_get_danger_set_bitmap_creation_count(void)
{
return s_danger_set_bitmap_creation_count;
}
ULong thread_get_danger_set_bitmap2_creation_count(void)
{
return s_danger_set_bitmap2_creation_count;
}