| /* |
| 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_clientobj.h" |
| #include "drd_error.h" |
| #include "drd_semaphore.h" |
| #include "drd_suppression.h" |
| #include "priv_drd_clientreq.h" |
| #include "pub_tool_errormgr.h" // VG_(maybe_record_error)() |
| #include "pub_tool_libcassert.h" // tl_assert() |
| #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 semaphore_cleanup(struct semaphore_info* p); |
| |
| |
| // Local variables. |
| |
| static Bool s_trace_semaphore; |
| |
| |
| // Function definitions. |
| |
| void semaphore_set_trace(const Bool trace_semaphore) |
| { |
| s_trace_semaphore = trace_semaphore; |
| } |
| |
| static |
| void semaphore_initialize(struct semaphore_info* const p, |
| const Addr semaphore, const UWord value) |
| { |
| tl_assert(semaphore != 0); |
| tl_assert(p->a1 == semaphore); |
| tl_assert(p->type == ClientSemaphore); |
| |
| p->cleanup = (void(*)(DrdClientobj*))semaphore_cleanup; |
| p->value = value; |
| p->waiters = 0; |
| p->last_sem_post_tid = DRD_INVALID_THREADID; |
| p->last_sem_post_segment = 0; |
| } |
| |
| /** Free the memory that was allocated by semaphore_initialize(). Called by |
| * clientobj_remove(). |
| */ |
| static void semaphore_cleanup(struct semaphore_info* p) |
| { |
| if (p->waiters > 0) |
| { |
| SemaphoreErrInfo sei = { p->a1 }; |
| VG_(maybe_record_error)(VG_(get_running_tid)(), |
| SemaphoreErr, |
| VG_(get_IP)(VG_(get_running_tid)()), |
| "Destruction of semaphore that is being waited" |
| " upon", |
| &sei); |
| } |
| sg_put(p->last_sem_post_segment); |
| } |
| |
| static |
| struct semaphore_info* |
| semaphore_get_or_allocate(const Addr semaphore) |
| { |
| struct semaphore_info *p; |
| |
| tl_assert(offsetof(DrdClientobj, semaphore) == 0); |
| p = &clientobj_get(semaphore, ClientSemaphore)->semaphore; |
| if (p == 0) |
| { |
| tl_assert(offsetof(DrdClientobj, semaphore) == 0); |
| p = &clientobj_add(semaphore, ClientSemaphore)->semaphore; |
| semaphore_initialize(p, semaphore, 0); |
| } |
| return p; |
| } |
| |
| static struct semaphore_info* semaphore_get(const Addr semaphore) |
| { |
| tl_assert(offsetof(DrdClientobj, semaphore) == 0); |
| return &clientobj_get(semaphore, ClientSemaphore)->semaphore; |
| } |
| |
| /** Called before sem_init(). */ |
| struct semaphore_info* semaphore_init(const Addr semaphore, |
| const Word pshared, const UWord value) |
| { |
| struct semaphore_info* p; |
| |
| if (s_trace_semaphore) |
| { |
| VG_(message)(Vg_UserMsg, |
| "[%d/%d] semaphore_init 0x%lx", |
| VG_(get_running_tid)(), |
| thread_get_running_tid(), |
| semaphore); |
| } |
| if (semaphore_get(semaphore)) |
| { |
| // To do: print an error message that a semaphore is being reinitialized. |
| } |
| p = semaphore_get_or_allocate(semaphore); |
| p->value = value; |
| return p; |
| } |
| |
| /** Called after sem_destroy(). */ |
| void semaphore_destroy(const Addr semaphore) |
| { |
| struct semaphore_info* p; |
| |
| if (s_trace_semaphore) |
| { |
| VG_(message)(Vg_UserMsg, |
| "[%d/%d] semaphore_destroy 0x%lx", |
| VG_(get_running_tid)(), |
| thread_get_running_tid(), |
| semaphore); |
| } |
| |
| p = semaphore_get(semaphore); |
| |
| if (p == 0) |
| { |
| GenericErrInfo GEI; |
| VG_(maybe_record_error)(VG_(get_running_tid)(), |
| GenericErr, |
| VG_(get_IP)(VG_(get_running_tid)()), |
| "Not a semaphore", |
| &GEI); |
| return; |
| } |
| |
| clientobj_remove(semaphore, ClientSemaphore); |
| } |
| |
| /** Called before sem_wait(). */ |
| void semaphore_pre_wait(const Addr semaphore) |
| { |
| struct semaphore_info* p; |
| |
| p = semaphore_get_or_allocate(semaphore); |
| if (s_trace_semaphore) |
| { |
| VG_(message)(Vg_UserMsg, |
| "[%d/%d] semaphore_pre_wait 0x%lx", |
| VG_(get_running_tid)(), |
| thread_get_running_tid(), |
| semaphore); |
| } |
| tl_assert(p); |
| tl_assert(p->waiters >= 0); |
| p->waiters++; |
| tl_assert(p->waiters > 0); |
| } |
| |
| /** Called after sem_wait() finished. |
| * @note Do not rely on the value of 'waited' -- some glibc versions do |
| * not set it correctly. |
| */ |
| void semaphore_post_wait(const DrdThreadId tid, const Addr semaphore, |
| const Bool waited) |
| { |
| struct semaphore_info* p; |
| |
| p = semaphore_get(semaphore); |
| if (s_trace_semaphore) |
| { |
| VG_(message)(Vg_UserMsg, |
| "[%d/%d] semaphore_post_wait 0x%lx", |
| VG_(get_running_tid)(), |
| thread_get_running_tid(), |
| semaphore); |
| } |
| tl_assert(p->waiters > 0); |
| p->waiters--; |
| tl_assert(p->waiters >= 0); |
| tl_assert(p->value >= 0); |
| if (p->value == 0) |
| { |
| SemaphoreErrInfo sei = { semaphore }; |
| VG_(maybe_record_error)(VG_(get_running_tid)(), |
| SemaphoreErr, |
| VG_(get_IP)(VG_(get_running_tid)()), |
| "Invalid semaphore", |
| &sei); |
| return; |
| } |
| p->value--; |
| tl_assert(p->value >= 0); |
| if (p->last_sem_post_tid != tid |
| && p->last_sem_post_tid != DRD_INVALID_THREADID) |
| { |
| tl_assert(p->last_sem_post_segment); |
| thread_combine_vc2(tid, &p->last_sem_post_segment->vc); |
| } |
| thread_new_segment(tid); |
| } |
| |
| /** Called before sem_post(). */ |
| void semaphore_pre_post(const DrdThreadId tid, const Addr semaphore) |
| { |
| struct semaphore_info* p; |
| |
| if (s_trace_semaphore) |
| { |
| VG_(message)(Vg_UserMsg, |
| "[%d/%d] semaphore_post 0x%lx", |
| VG_(get_running_tid)(), |
| thread_get_running_tid(), |
| semaphore); |
| } |
| p = semaphore_get_or_allocate(semaphore); |
| p->value++; |
| if (p->value == 1) |
| { |
| p->last_sem_post_tid = tid; |
| thread_new_segment(tid); |
| thread_get_latest_segment(&p->last_sem_post_segment, tid); |
| } |
| } |
| |
| /** Called after sem_post() finished successfully. */ |
| void semaphore_post_post(const DrdThreadId tid, const Addr semaphore, |
| const Bool waited) |
| { |
| /* Note: it is hard to implement the sem_post() wrapper correctly in */ |
| /* case sem_post() returns an error code. This is because handling this */ |
| /* case correctly requires restoring the vector clock associated with */ |
| /* the semaphore to its original value here. In order to do that without */ |
| /* introducing a race condition, extra locking has to be added around */ |
| /* each semaphore call. Such extra locking would have to be added in */ |
| /* drd_intercepts.c. However, it is hard to implement synchronization */ |
| /* in drd_intercepts.c in a portable way without calling already */ |
| /* redirected functions. */ |
| } |
| |
| void semaphore_thread_delete(const DrdThreadId threadid) |
| { } |