/*
This file is part of drd, a thread error detector.
Copyright (C) 2006-2015 Bart Van Assche <bvanassche@acm.org>.
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_clientobj.h"
#include "drd_cond.h"
#include "drd_error.h"
#include "drd_mutex.h"
#include "pub_tool_errormgr.h" /* VG_(maybe_record_error)() */
#include "pub_tool_libcassert.h" /* tl_assert() */
#include "pub_tool_libcbase.h" /* VG_(memcmp)() */
#include "pub_tool_libcprint.h" /* VG_(printf)() */
#include "pub_tool_machine.h" /* VG_(get_IP)() */
#include "pub_tool_threadstate.h" /* VG_(get_running_tid)() */
/* Local functions. */
static void DRD_(cond_cleanup)(struct cond_info* p);
/* Local variables. */
static Bool DRD_(s_report_signal_unlocked) = True;
static Bool DRD_(s_trace_cond);
/* Function definitions. */
void DRD_(cond_set_report_signal_unlocked)(const Bool r)
{
DRD_(s_report_signal_unlocked) = r;
}
void DRD_(cond_set_trace)(const Bool trace_cond)
{
DRD_(s_trace_cond) = trace_cond;
}
static
void DRD_(cond_initialize)(struct cond_info* const p, const Addr cond)
{
tl_assert(cond != 0);
tl_assert(p->a1 == cond);
tl_assert(p->type == ClientCondvar);
p->cleanup = (void(*)(DrdClientobj*))(DRD_(cond_cleanup));
p->delete_thread = 0;
p->waiter_count = 0;
p->mutex = 0;
}
/**
* Free the memory that was allocated by cond_initialize(). Called by
* DRD_(clientobj_remove)().
*/
static void DRD_(cond_cleanup)(struct cond_info* p)
{
tl_assert(p);
if (p->mutex)
{
struct mutex_info* q;
q = &(DRD_(clientobj_get)(p->mutex, ClientMutex)->mutex);
{
CondDestrErrInfo cde = {
DRD_(thread_get_running_tid)(),
p->a1,
q ? q->a1 : 0,
q ? q->owner : DRD_INVALID_THREADID
};
VG_(maybe_record_error)(VG_(get_running_tid)(),
CondDestrErr,
VG_(get_IP)(VG_(get_running_tid)()),
"Destroying condition variable that is being"
" waited upon",
&cde);
}
}
}
/**
* Report that the synchronization object at address 'addr' is of the
* wrong type.
*/
static void wrong_type(const Addr addr)
{
GenericErrInfo gei = {
.tid = DRD_(thread_get_running_tid)(),
.addr = addr,
};
VG_(maybe_record_error)(VG_(get_running_tid)(),
GenericErr,
VG_(get_IP)(VG_(get_running_tid)()),
"wrong type of synchronization object",
&gei);
}
static struct cond_info* cond_get_or_allocate(const Addr cond)
{
struct cond_info *p;
tl_assert(offsetof(DrdClientobj, cond) == 0);
p = &(DRD_(clientobj_get)(cond, ClientCondvar)->cond);
if (p)
return p;
if (DRD_(clientobj_present)(cond, cond + 1))
{
wrong_type(cond);
return 0;
}
p = &(DRD_(clientobj_add)(cond, ClientCondvar)->cond);
DRD_(cond_initialize)(p, cond);
return p;
}
struct cond_info* DRD_(cond_get)(const Addr cond)
{
tl_assert(offsetof(DrdClientobj, cond) == 0);
return &(DRD_(clientobj_get)(cond, ClientCondvar)->cond);
}
/** Called before pthread_cond_init(). */
void DRD_(cond_pre_init)(const Addr cond)
{
struct cond_info* p;
if (DRD_(s_trace_cond))
DRD_(trace_msg)("[%u] cond_init cond 0x%lx",
DRD_(thread_get_running_tid)(), cond);
p = DRD_(cond_get)(cond);
if (p) {
CondErrInfo cei = { .tid = DRD_(thread_get_running_tid)(), .cond = cond };
VG_(maybe_record_error)(VG_(get_running_tid)(),
CondErr,
VG_(get_IP)(VG_(get_running_tid)()),
"initialized twice",
&cei);
}
cond_get_or_allocate(cond);
}
/** Called after pthread_cond_destroy(). */
void DRD_(cond_post_destroy)(const Addr cond, const Bool destroy_succeeded)
{
struct cond_info* p;
if (DRD_(s_trace_cond))
DRD_(trace_msg)("[%u] cond_destroy cond 0x%lx",
DRD_(thread_get_running_tid)(), cond);
p = DRD_(cond_get)(cond);
if (p == 0)
{
CondErrInfo cei = { .tid = DRD_(thread_get_running_tid)(), .cond = cond };
VG_(maybe_record_error)(VG_(get_running_tid)(),
CondErr,
VG_(get_IP)(VG_(get_running_tid)()),
"not a condition variable",
&cei);
return;
}
if (p->waiter_count != 0)
{
CondErrInfo cei = { .tid = DRD_(thread_get_running_tid)(), .cond = cond };
VG_(maybe_record_error)(VG_(get_running_tid)(),
CondErr,
VG_(get_IP)(VG_(get_running_tid)()),
"destruction of condition variable being waited"
" upon",
&cei);
}
if (destroy_succeeded)
DRD_(clientobj_remove)(p->a1, ClientCondvar);
}
/**
* Called before pthread_cond_wait(). Note: before this function is called,
* mutex_unlock() has already been called from drd_clientreq.c.
*/
void DRD_(cond_pre_wait)(const Addr cond, const Addr mutex)
{
struct cond_info* p;
struct mutex_info* q;
if (DRD_(s_trace_cond))
DRD_(trace_msg)("[%u] cond_pre_wait cond 0x%lx",
DRD_(thread_get_running_tid)(), cond);
p = cond_get_or_allocate(cond);
if (!p)
{
CondErrInfo cei = { .tid = DRD_(thread_get_running_tid)(), .cond = cond };
VG_(maybe_record_error)(VG_(get_running_tid)(),
CondErr,
VG_(get_IP)(VG_(get_running_tid)()),
"not a condition variable",
&cei);
return;
}
if (p->waiter_count == 0)
{
p->mutex = mutex;
}
else if (p->mutex != mutex)
{
CondWaitErrInfo cwei
= { .tid = DRD_(thread_get_running_tid)(),
.cond = cond, .mutex1 = p->mutex, .mutex2 = mutex };
VG_(maybe_record_error)(VG_(get_running_tid)(),
CondWaitErr,
VG_(get_IP)(VG_(get_running_tid)()),
"Inconsistent association of condition variable"
" and mutex",
&cwei);
}
tl_assert(p->mutex);
q = DRD_(mutex_get)(p->mutex);
if (q
&& q->owner == DRD_(thread_get_running_tid)() && q->recursion_count > 0)
{
const ThreadId vg_tid = VG_(get_running_tid)();
MutexErrInfo MEI = { DRD_(thread_get_running_tid)(),
q->a1, q->recursion_count, q->owner };
VG_(maybe_record_error)(vg_tid,
MutexErr,
VG_(get_IP)(vg_tid),
"Mutex locked recursively",
&MEI);
}
else if (q == 0)
{
DRD_(not_a_mutex)(p->mutex);
}
++p->waiter_count;
}
/**
* Called after pthread_cond_wait().
*/
void DRD_(cond_post_wait)(const Addr cond)
{
struct cond_info* p;
if (DRD_(s_trace_cond))
DRD_(trace_msg)("[%u] cond_post_wait cond 0x%lx",
DRD_(thread_get_running_tid)(), cond);
p = DRD_(cond_get)(cond);
if (!p)
{
CondDestrErrInfo cde = {
DRD_(thread_get_running_tid)(), cond, 0, DRD_INVALID_THREADID
};
VG_(maybe_record_error)(VG_(get_running_tid)(),
CondDestrErr,
VG_(get_IP)(VG_(get_running_tid)()),
"condition variable has been destroyed while"
" being waited upon",
&cde);
return;
}
if (p->waiter_count > 0)
{
--p->waiter_count;
if (p->waiter_count == 0)
{
p->mutex = 0;
}
}
}
static void cond_signal(const DrdThreadId tid, struct cond_info* const cond_p)
{
const ThreadId vg_tid = VG_(get_running_tid)();
const DrdThreadId drd_tid = DRD_(VgThreadIdToDrdThreadId)(vg_tid);
tl_assert(cond_p);
if (cond_p->waiter_count > 0)
{
if (DRD_(s_report_signal_unlocked)
&& ! DRD_(mutex_is_locked_by)(cond_p->mutex, drd_tid))
{
/*
* A signal is sent while the associated mutex has not been locked.
* This can indicate but is not necessarily a race condition.
*/
CondRaceErrInfo cei = { .tid = DRD_(thread_get_running_tid)(),
.cond = cond_p->a1,
.mutex = cond_p->mutex,
};
VG_(maybe_record_error)(vg_tid,
CondRaceErr,
VG_(get_IP)(vg_tid),
"CondErr",
&cei);
}
}
else
{
/*
* No other thread is waiting for the signal, hence the signal will
* be lost. This is normal in a POSIX threads application.
*/
}
}
static void not_initialized(Addr const cond)
{
CondErrInfo cei = { .tid = DRD_(thread_get_running_tid)(), .cond = cond };
VG_(maybe_record_error)(VG_(get_running_tid)(),
CondErr,
VG_(get_IP)(VG_(get_running_tid)()),
"condition variable has not been initialized",
&cei);
}
/** Called before pthread_cond_signal(). */
void DRD_(cond_pre_signal)(Addr const cond)
{
struct cond_info* p;
p = DRD_(cond_get)(cond);
if (DRD_(s_trace_cond))
DRD_(trace_msg)("[%u] cond_signal cond 0x%lx",
DRD_(thread_get_running_tid)(), cond);
tl_assert(DRD_(pthread_cond_initializer));
if (!p && VG_(memcmp)((void*)cond, (void*)DRD_(pthread_cond_initializer),
DRD_(pthread_cond_initializer_size)) != 0)
{
not_initialized(cond);
return;
}
if (!p)
p = cond_get_or_allocate(cond);
cond_signal(DRD_(thread_get_running_tid)(), p);
}
/** Called before pthread_cond_broadcast(). */
void DRD_(cond_pre_broadcast)(Addr const cond)
{
struct cond_info* p;
if (DRD_(s_trace_cond))
DRD_(trace_msg)("[%u] cond_broadcast cond 0x%lx",
DRD_(thread_get_running_tid)(), cond);
p = DRD_(cond_get)(cond);
tl_assert(DRD_(pthread_cond_initializer));
if (!p && VG_(memcmp)((void*)cond, (void*)DRD_(pthread_cond_initializer),
DRD_(pthread_cond_initializer_size)) != 0)
{
not_initialized(cond);
return;
}
if (!p)
p = cond_get_or_allocate(cond);
cond_signal(DRD_(thread_get_running_tid)(), p);
}