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ChangeLog
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2010-06-19 Ross Johnson <ross.johnson at homemail.com.au>
* ptw32_MCS_lock.c (ptw32_mcs_node_substitute): Fix variable
names to avoid using C++ keyword ("new").
* implement.h (ptw32_mcs_node_substitute): Likewise.
* pthread_barrier_wait.c: Fix signed/unsigned comparison warning.
2010-06-18 Ramiro Polla <ramiro.polla at gmail.com >
* autostatic.c: New file; call pthread_win32_process_*()
libary init/cleanup routines automatically on application start
when statically linked.
* pthread.c (autostatic.c): Included.
* pthread.h (declspec): Remove import/export defines if compiler
is MINGW.
* sched.h (declspec): Likewise.
* semaphore.h (declspec): Likewise.
* need_errno.h (declspec): Likewise.
* Makefile (autostatic.obj): Add for small static builds.
* GNUmakefile (autostatic.o): Likewise.
* NEWS (Version 2.9.0): Add changes.
* README.NONPORTABLE (pthread_win32_process_*): Update
description.
2010-06-15 Ramiro Polla <ramiro.polla at gmail.com >
* Makefile: Remove linkage with the winsock library by default.
* GNUmakefile: Likewise.
* pthread_getspecific.c: Likewise by removing calls to WSA
functions.
* config.h (RETAIN_WSALASTERROR): Can be defined if necessary.
2010-01-26 Ross Johnson <ross.johnson at homemail.com.au>
* ptw32_MCS_lock.c (ptw32_mcs_node_substitute): New routine
to allow relocating the lock owners thread-local node to somewhere
else, e.g. to global space so that another thread can release the
lock. Used in pthread_barrier_wait.
(ptw32_mcs_lock_try_acquire): New routine.
* pthread_barrier_init: Only one semaphore is used now.
* pthread_barrier_wait: Added an MCS guard lock with the last thread
to leave the barrier releasing the lock. This removes a deadlock bug
observed when there are greater than barrier-count threads
attempting to cross.
* pthread_barrier_destroy: Added an MCS guard lock.
2006-12-20 Ross Johnson <ross.johnson at homemail.com.au>
* sem_destroy.c: Fix the race involving invalidation of the sema;
fix incorrect return of EBUSY resulting from the mutex trylock
on the private mutex guard.
* sem_wait.c: Add check for invalid sem_t after acquiring the
sem_t state guard mutex and before affecting changes to sema state.
* sem_trywait.c: Likewise.
* sem_timedwait.c: Likewise.
* sem_getvalue.c: Likewise.
* sem_post.c: Similar.
* sem_post_multiple.c: Likewise.
* sem_init.c: Set max Win32 semaphore count to SEM_VALUE_MAX (was
_POSIX_SEM_VALUE_MAX, which is a lower value - the minimum).
* pthread_win32_attach_detach_np.c (pthread_win32_process_attach_np):
Load COREDLL.DLL under WINCE to check existence of
InterlockedCompareExchange() routine. This used to be done to test
for TryEnterCriticalSection() but was removed when this was no
longer needed.
2006-01-25 Prashant Thakre <prashant.thakre at gmail.com>
* pthread_cancel.c: Added _M_IA64 register context support.
2005-05-13 Ross Johnson <ross at callisto.canberra.edu.au>
* pthread_kill.c (pthread_kill): Remove check for Win32 thread
priority (to confirm HANDLE validity). Useless since thread HANDLEs
a not recycle-unique.
2005-05-30 Vladimir Kliatchko <vladimir at kliatchko.com>
* pthread_once.c: Re-implement using an MCS queue-based lock. The form
of pthread_once is as proposed by Alexander Terekhov (see entry of
2005-03-13). The MCS lock implementation does not require a unique
'name' to identify the lock between threads. Attempts to get the Event
or Semaphore based versions of pthread_once to a satisfactory level
of robustness have thus far failed. The last problem (avoiding races
involving non recycle-unique Win32 HANDLEs) was giving everyone
grey hair trying to solve it.
* ptw32_MCS_lock.c: New MCS queue-based lock implementation. These
locks are efficient: they have very low overhead in the uncontended case;
are efficient in contention and minimise cache-coherence updates in
managing the user level FIFO queue; do not require an ABI change in the
library.
2005-05-27 Alexander Gottwald <alexander.gottwald at s1999.tu-chemnitz.de>
* pthread.h: Some things, like HANDLE, were only defined if
PTW32_LEVEL was >= 3. They should always be defined.
2005-05-25 Vladimir Kliatchko <vladimir at kliatchko.com>
* pthread_once.c: Eliminate all priority operations and other
complexity by replacing the event with a semaphore. The advantage
of the change is the ability to release just one waiter if the
init_routine thread is cancelled yet still release all waiters when
done. Simplify once_control state checks to improve efficiency
further.
2005-05-24 Mikael Magnusson <mikaelmagnusson at glocalnet.net>
* GNUmakefile: Patched to allow cross-compile with mingw32 on Linux.
It uses macros instead of referencing dlltool, gcc and g++ directly;
added a call to ranlib. For example the GC static library can be
built with:
make CC=i586-mingw32msvc-gcc RC=i586-mingw32msvc-windres \
RANLIB=i586-mingw32msvc-ranlib clean GC-static
2005-05-13 Ross Johnson <ross at callisto.canberra.edu.au>
* pthread_win32_attach_detach_np.c (pthread_win32_thread_detach_np):
Move on-exit-only stuff from ptw32_threadDestroy() to here.
* ptw32_threadDestroy.c: It's purpose is now only to reclaim thread
resources for detached threads, or via pthread_join() or
pthread_detach() on joinable threads.
* ptw32_threadStart.c: Calling user destruct routines has moved to
pthread_win32_thread_detach_np(); call pthread_win32_thread_detach_np()
directly if statically linking, otherwise do so via dllMain; store
thread return value in thread struct for all cases, including
cancellation and exception exits; thread abnormal exits go via
pthread_win32_thread_detach_np.
* pthread_join.c (pthread_join): Don't try to get return code from
Win32 thread - always get it from he thread struct.
* pthread_detach.c (pthread_detach): reduce extent of the thread
existence check since we now don't care if the Win32 thread HANDLE has
been closed; reclaim thread resources if the thread has exited already.
* ptw32_throw.c (ptw32_throw): For Win32 threads that are not implicit,
only Call thread cleanup if statically linking, otherwise leave it to
dllMain.
* sem_post.c (_POSIX_SEM_VALUE_MAX): Change to SEM_VALUE_MAX.
* sem_post_multiple.c: Likewise.
* sem_init.c: Likewise.
2005-05-10 Ross Johnson <ross at callisto.canberra.edu.au>
* pthread_join.c (pthread_join): Add missing check for thread ID
reference count in thread existence test; reduce extent of the
existence test since we don't care if the Win32 thread HANDLE has
been closed.
2005-05-09 Ross Johnson <ross at callisto.canberra.edu.au>
* ptw32_callUserDestroyRoutines.c: Run destructor process (i.e.
loop over all keys calling destructors) up to
PTHREAD_DESTRUCTOR_ITERATIONS times if TSD value isn't NULL yet;
modify assoc management.
* pthread_key_delete.c: Modify assoc management.
* ptw32_tkAssocDestroy.c: Fix error in assoc removal from chains.
* pthread.h
(_POSIX_THREAD_DESTRUCTOR_ITERATIONS): Define to value specified by
POSIX.
(_POSIX_THREAD_KEYS_MAX): Define to value specified by POSIX.
(PTHREAD_KEYS_MAX): Redefine [upward] to minimum required by POSIX.
(SEM_NSEMS_MAX): Define to implementation value.
(SEM_VALUE_MAX): Define to implementation value.
(_POSIX_SEM_NSEMS_MAX): Redefine to value specified by POSIX.
(_POSIX_SEM_VALUE_MAX): Redefine to value specified by POSIX.
2005-05-06 Ross Johnson <ross at callisto.canberra.edu.au>
* signal.c (sigwait): Add a cancellation point to this otherwise
no-op.
* sem_init.c (sem_init): Check for and return ERANGE error.
* sem_post.c (sem_post): Likewise.
* sem_post_multiple.c (sem_post_multiple): Likewise.
* manual (directory): Added; see ChangeLog inside.
2005-05-02 Ross Johnson <ross at callisto.canberra.edu.au>
* implement.h (struct pthread_key_t_): Change threadsLock to keyLock
so as not to be confused with the per thread lock 'threadlock';
change all references to it.
* implement.h (struct ThreadKeyAssoc): Remove lock; add prevKey
and prevThread pointers; re-implemented all routines that use this
struct. The effect of this is to save one handle per association,
which could potentially equal the number of keys multiplied by the
number of threads, accumulating over time - and to free the
association memory as soon as it is no longer referenced by either
the key or the thread. Previously, the handle and memory were
released only after BOTH key and thread no longer referenced the
association. That is, often no association resources were released
until the process itself exited. In addition, at least one race
condition has been removed - where two threads could attempt to
release the association resources simultaneously - one via
ptw32_callUserDestroyRoutines and the other via
pthread_key_delete.
- thanks to Richard Hughes at Aculab for discovering the problem.
* pthread_key_create.c: See above.
* pthread_key_delete.c: See above.
* pthread_setspecific.c: See above.
* ptw32_callUserDestroyRoutines.c: See above.
* ptw32_tkAssocCreate.c: See above.
* ptw32_tkAssocDestroy.c: See above.
2005-04-27 Ross Johnson <ross at callisto.canberra.edu.au>
* sem_wait.c (ptw32_sem_wait_cleanup): after cancellation re-attempt
to acquire the semaphore to avoid a race with a late sem_post.
* sem_timedwait.c: Modify comments.
2005-04-25 Ross Johnson <ross at callisto.canberra.edu.au>
* ptw32_relmillisecs.c: New module; converts future abstime to
milliseconds relative to 'now'.
* pthread_mutex_timedlock.c: Use new ptw32_relmillisecs routine in
place of internal code; remove the NEED_SEM code - this routine is now
implemented for builds that define NEED_SEM (WinCE etc)
* sem_timedwait.c: Likewise; after timeout or cancellation,
re-attempt to acquire the semaphore in case one has been posted since
the timeout/cancel occurred. Thanks to Stefan Mueller.
* Makefile: Add ptw32_relmillisecs.c module; remove
ptw32_{in,de}crease_semaphore.c modules.
* GNUmakefile: Likewise.
* Bmakefile: Likewise.
* sem_init.c: Re-write the NEED_SEM code to be consistent with the
non-NEED_SEM code, but retaining use of an event in place of the w32 sema
for w32 systems that don't include semaphores (WinCE);
the NEED_SEM versions of semaphores has been broken for a long time but is
now fixed and supports all of the same routines as the non-NEED_SEM case.
* sem_destroy.c: Likewise.
* sem_wait.c: Likewise.
* sem_post.c: Likewise.
* sem_post_multple.c: Likewise.
* implement.h: Likewise.
* sem_timedwait.c: Likewise; this routine is now
implemented for builds that define NEED_SEM (WinCE etc).
* sem_trywait.c: Likewise.
* sem_getvalue.c: Likewise.
* pthread_once.c: Yet more changes, reverting closer to Gottlob Frege's
first design, but retaining cancellation, priority boosting, and adding
preservation of W32 error codes to make pthread_once transparent to
GetLastError.
2005-04-11 Ross Johnson <ross at callisto.canberra.edu.au>
* pthread_once.c (pthread_once): Added priority boosting to
solve starvation problem after once_routine cancellation.
See notes in file.
2005-04-06 Kevin Lussier <Kevin at codegreennetworks.com>
* Makefile: Added debug targets for all versions of the library.
2005-04-01 Ross Johnson <ross at callisto.canberra.edu.au>
* GNUmakefile: Add target to build libpthreadGC1.a as a static link
library.
* Makefile: Likewise for pthreadGC1.lib.
2005-04-01 Kevin Lussier <Kevin at codegreennetworks.com>
* sem_timedwait.c (sem_timedwait): Increase size of temp variables to
avoid int overflows for large timeout values.
* implement.h (int64_t): Include or define.
2005-03-31 Dimitar Panayotov <develop at mail.bg>^M
* pthread.h: Fix conditional defines for static linking.
* sched.h: Liekwise.
* semaphore.h: Likewise.
* dll.c (PTW32_STATIC_LIB): Module is conditionally included
in the build.
2005-03-16 Ross Johnson <ross at callisto.canberra.edu.au>^M
* pthread_setcancelstate.c: Undo the last change.
2005-03-16 Ross Johnson <ross at callisto.canberra.edu.au>^M
* pthread_setcancelstate.c: Don't check for an async cancel event
if the library is using alertable async cancel..
2005-03-14 Ross Johnson <ross at callisto.canberra.edu.au>
* pthread_once.c (pthread_once): Downgrade interlocked operations to simple
memory operations where these are protected by the critical section; edit
comments.
2005-03-13 Ross Johnson <rpj at callisto.canberra.edu.au>
* pthread_once.c (pthread_once): Completely redesigned; a change was
required to the ABI (pthread_once_t_), and resulting in a version
compatibility index increment.
NOTES:
The design (based on pseudo code contributed by Gottlob Frege) avoids
creating a kernel object if there is no contention. See URL for details:-
http://sources.redhat.com/ml/pthreads-win32/2005/msg00029.html
This uses late initialisation similar to the technique already used for
pthreads-win32 mutexes and semaphores (from Alexander Terekhov).
The subsequent cancelation cleanup additions (by rpj) could not be implemented
without sacrificing some of the efficiency in Gottlob's design. In particular,
although each once_control uses it's own event to block on, a global CS is
required to manage it - since the event must be either re-usable or
re-creatable under cancelation. This is not needed in the non-cancelable
design because it is able to mark the event as closed (forever).
When uncontested, a CS operation is equivalent to an Interlocked operation
in speed. So, in the final design with cancelability, an uncontested
once_control operation involves a minimum of five interlocked operations
(including the LeaveCS operation).
ALTERNATIVES:
An alternative design from Alexander Terekhov proposed using a named mutex,
as sketched below:-
if (!once_control) { // May be in TLS
named_mutex::guard guard(&once_control2);
if (!once_control2) {
<init>
once_control2 = true;
}
once_control = true;
}
A more detailed description of this can be found here:-
http://groups.yahoo.com/group/boost/message/15442
[Although the definition of a suitable PTHREAD_ONCE_INIT precludes use of the
TLS located flag, this is not critical.]
There are three primary concerns though:-
1) The [named] mutex is 'created' even in the uncontended case.
2) A system wide unique name must be generated.
3) Win32 mutexes are VERY slow even in the uncontended case. An uncontested
Win32 mutex lock operation can be 50 (or more) times slower than an
uncontested EnterCS operation.
Ultimately, the named mutex trick is making use of the global locks maintained
by the kernel.
* pthread.h (pthread_once_t_): One flag and an event HANDLE added.
(PTHREAD_ONCE_INIT): Additional values included.
2005-03-08 Ross Johnson <rpj at callisto.canberra.edu.au>
* pthread_once.c (pthread_once): Redesigned to elliminate potential
starvation problem.
- reported by Gottlob Frege <gottlobfrege at gmail.com>
* ptw32_threadDestroy.c (ptw32_threadDestroy): Implicit threads were
not closing their Win32 thread duplicate handle.
- reported by Dmitrii Semii <bogolt at gmail.com>
2005-01-25 Ralf Kubis <RKubis at mc.com>
* Attempted acquisition of recursive mutex was causing waiting
threads to not be woken when the mutex is released.
* GNUmakefile (GCE): Generate correct version resource comments.
2005-01-01 Konstantin Voronkov <beowinkle at yahoo.com>
* pthread_mutex_lock.c (pthread_mutex_lock): The new atomic exchange
mutex algorithm is known to allow a thread to steal the lock off
FIFO waiting threads. The next waiting FIFO thread gets a spurious
wake-up and must attempt to re-acquire the lock. The woken thread
was setting itself as the mutex's owner before the re-acquisition.
2004-11-22 Ross Johnson <rpj at callisto.canberra.edu.au>
* pthread_cond_wait.c (ptw32_cond_wait_cleanup): Undo change
from 2004-11-02.
* Makefile (DLL_VER): Added for DLL naming suffix - see README.
* GNUmakefile (DLL_VER): Likewise.
* Wmakefile (DLL_VER): Likewise.
* Bmakefile (DLL_VER): Likewise.
* pthread.dsw (version.rc): Added to MSVS workspace.
2004-11-20 Boudewijn Dekker <b.dekker at ellipsis.nl>
* pthread_getspecific.c (pthread_getspecific): Check for
invalid (NULL) key argument.
2004-11-19 Ross Johnson <rpj at callisto.canberra.edu.au>
* config.h (PTW32_THREAD_ID_REUSE_INCREMENT): Added to allow
building the library for either unique thread IDs like Solaris
or non-unique thread IDs like Linux; allows application developers
to override the library's default insensitivity to some apps
that may not be strictly POSIX compliant.
* version.rc: New resource module to encode version information
within the DLL.
* pthread.h: Added PTW32_VERSION* defines and grouped sections
required by resource compiler together; bulk of file is skipped
if RC_INVOKED. Defined some error numbers and other names for
Borland compiler.
2004-11-02 Ross Johnson <rpj at callisto.canberra.edu.au>
* pthread_cond_wait.c (ptw32_cond_wait_cleanup): Lock CV mutex at
start of cleanup handler rather than at the end.
* implement.h (PTW32_THREAD_REUSE_EMPTY): Renamed from *_BOTTOM.
(ptw32_threadReuseBottom): New global variable.
* global.c (ptw32_threadReuseBottom): Declare new variable.
* ptw32_reuse.c (ptw32_reuse): Change reuse LIFO stack to LILO queue
to more evenly distribute use of reusable thread IDs; use renamed
PTW32_THREAD_REUSE_EMPTY.
* ptw32_processTerminate.c (ptw2_processTerminate): Use renamed
PTW32_THREAD_REUSE_EMPTY.
2004-10-31 Ross Johnson <rpj at callisto.canberra.edu.au>
* implement.h (PThreadState): Add new state value
'PThreadStateCancelPending'.
* pthread_testcancel.c (pthread_testcancel): Use new thread
'PThreadStateCancelPending' state as short cut to avoid entering
kernel space via WaitForSingleObject() call. This was obviated
by user space sema acquisition in sem_wait() and sem_timedwait(),
which are also cancelation points. A call to pthread_testcancel()
was required, which introduced a kernel call, effectively nullifying
any gains made by the user space sem acquisition checks.
* pthread_cancel.c (pthread_cancel): Set new thread
'PThreadStateCancelPending' state.
2004-10-29 Ross Johnson <rpj at callisto.canberra.edu.au>
* implement.h (pthread_t): Renamed to ptw32_thread_t; struct contains
all thread state.
* pthread.h (ptw32_handle_t): New general purpose struct to serve
as a handle for various reusable object IDs - currently only used
by pthread_t; contains a pointer to ptw32_thread_t (thread state)
and a general purpose uint for use as a reuse counter or flags etc.
(pthread_t): typedef'ed to ptw32_handle_t; the uint is the reuse
counter that allows the library to maintain unique POSIX thread IDs.
When the pthread struct reuse stack was introduced, threads would
often acquire an identical ID to a previously destroyed thread. The
same was true for the pre-reuse stack library, by virtue of pthread_t
being the address of the thread struct. The new pthread_t retains
the reuse stack but provides virtually unique thread IDs.
* sem_wait.c (ptw32_sem_wait_cleanup): New routine used for
cancelation cleanup.
* sem_timedwait.c (ptw32_sem_timedwait_cleanup): Likewise.
2004-10-22 Ross Johnson <rpj at callisto.canberra.edu.au>
* sem_init.c (sem_init): Introduce a 'lock' element in order to
replace the interlocked operations with conventional serialisation.
This is needed in order to be able to atomically modify the sema
value and perform Win32 sema release operations. Win32 semaphores are
used instead of events in order to support efficient multiple posting.
If the whole modify/release isn't atomic, a race between
sem_timedwait() and sem_post() could result in a release when there is
no waiting semaphore, which would cause too many threads to proceed.
* sem_wait.c (sem_wait): Use new 'lock'element.
* sem_timedwait.c (sem_timedwait): Likewise.
* sem_trywait.c (sem_trywait): Likewise.
* sem_post.c (sem_post): Likewise.
* sem_post_multiple.c (sem_post_multiple): Likewise.
* sem_getvalue.c (sem_getvalue): Likewise.
* ptw32_semwait.c (ptw32_semwait): Likewise.
* sem_destroy.c (sem_destroy): Likewise; also tightened the conditions
for semaphore destruction; in particular, a semaphore will not be
destroyed if it has waiters.
* sem_timedwait.c (sem_timedwait): Added cancel cleanup handler to
restore sema value when cancelled.
* sem_wait.c (sem_wait): Likewise.
2004-10-21 Ross Johnson <rpj at callisto.canberra.edu.au>
* pthread_mutex_unlock.c (pthread_mutex_unlock): Must use PulseEvent()
rather than SetEvent() to reset the event if there are no waiters.
2004-10-19 Ross Johnson <rpj at callisto.canberra.edu.au>
* sem_init.c (sem_init): New semaphore model based on the same idea
as mutexes, i.e. user space interlocked check to avoid
unnecessarily entering kernel space. Wraps the Win32 semaphore and
keeps it's own counter. Although the motivation to do this has existed
for a long time, credit goes to Alexander Terekhov for providing
the logic. I have deviated slightly from AT's logic to add the waiters
count, which has made the code more complicated by adding cancelation
cleanup. This also appears to have broken the VCE (C++ EH) version of
the library (the same problem as previously reported - see BUGS #2),
only apparently not fixable using the usual workaround, nor by turning
all optimisation off. The GCE version works fine, so it is presumed to
be a bug in MSVC++ 6.0. The cancelation exception is thrown and caught
correctly, but the cleanup class destructor is never called. The failing
test is tests\semaphore4.c.
* sem_wait.c (sem_wait): Implemented user space check model.
* sem_post.c (sem_post): Likewise.
* sem_trywait.c (sem_trywait): Likewise.
* sem_timedwait.c (sem_timedwait): Likewise.
* sem_post_multiple.c (sem_post_multiple): Likewise.
* sem_getvalue.c (sem_getvalue): Likewise.
* ptw32_semwait.c (ptw32_semwait): Likewise.
* implement.h (sem_t_): Add counter element.
2004-10-15 Ross Johnson <rpj at callisto.canberra.edu.au>
* implement.h (pthread_mutex_t_): Use an event in place of
the POSIX semaphore.
* pthread_mutex_init.c: Create the event; remove semaphore init.
* pthread_mutex_destroy.c: Delete the event.
* pthread_mutex_lock.c: Replace the semaphore wait with the event wait.
* pthread_mutex_trylock.c: Likewise.
* pthread_mutex_timedlock.c: Likewise.
* pthread_mutex_unlock.c: Set the event.
2004-10-14 Ross Johnson <rpj at callisto.canberra.edu.au>
* pthread_mutex_lock.c (pthread_mutex_lock): New algorithm using
Terekhov's xchg based variation of Drepper's cmpxchg model.
Theoretically, xchg uses fewer clock cycles than cmpxchg (using IA-32
as a reference), however, in my opinion bus locking dominates the
equation on smp systems, so the model with the least number of bus
lock operations in the execution path should win, which is Terekhov's
variant. On IA-32 uni-processor systems, it's faster to use the
CMPXCHG instruction without locking the bus than to use the XCHG
instruction, which always locks the bus. This makes the two variants
equal for the non-contended lock (fast lane) execution path on up
IA-32. Testing shows that the xchg variant is faster on up IA-32 as
well if the test forces higher lock contention frequency, even though
kernel calls should be dominating the times (on up IA-32, both
variants used CMPXCHG instructions and neither locked the bus).
* pthread_mutex_timedlock.c pthread_mutex_timedlock(): Similarly.
* pthread_mutex_trylock.c (pthread_mutex_trylock): Similarly.
* pthread_mutex_unlock.c (pthread_mutex_unlock): Similarly.
* ptw32_InterlockedCompareExchange.c (ptw32_InterlockExchange): New
function.
(PTW32_INTERLOCKED_EXCHANGE): Sets up macro to use inlined
ptw32_InterlockedExchange.
* implement.h (PTW32_INTERLOCKED_EXCHANGE): Set default to
InterlockedExchange().
* Makefile: Building using /Ob2 so that asm sections within inline
functions are inlined.
2004-10-08 Ross Johnson <rpj at callisto.canberra.edu.au>
* pthread_mutex_destroy.c (pthread_mutex_destroy): Critical Section
element is no longer required.
* pthread_mutex_init.c (pthread_mutex_init): Likewise.
* pthread_mutex_lock.c (pthread_mutex_lock): New algorithm following
Drepper's paper at http://people.redhat.com/drepper/futex.pdf, but
using the existing semaphore in place of the futex described in the
paper. Idea suggested by Alexander Terekhov - see:
http://sources.redhat.com/ml/pthreads-win32/2003/msg00108.html
* pthread_mutex_timedlock.c pthread_mutex_timedlock(): Similarly.
* pthread_mutex_trylock.c (pthread_mutex_trylock): Similarly.
* pthread_mutex_unlock.c (pthread_mutex_unlock): Similarly.
* pthread_barrier_wait.c (pthread_barrier_wait): Use inlined version
of InterlockedCompareExchange() if possible - determined at
build-time.
* pthread_spin_destroy.c pthread_spin_destroy(): Likewise.
* pthread_spin_lock.c pthread_spin_lock():Likewise.
* pthread_spin_trylock.c (pthread_spin_trylock):Likewise.
* pthread_spin_unlock.c (pthread_spin_unlock):Likewise.
* ptw32_InterlockedCompareExchange.c: Sets up macro for inlined use.
* implement.h (pthread_mutex_t_): Remove Critical Section element.
(PTW32_INTERLOCKED_COMPARE_EXCHANGE): Set to default non-inlined
version of InterlockedCompareExchange().
* private.c: Include ptw32_InterlockedCompareExchange.c first for
inlining.
* GNUmakefile: Add commandline option to use inlined
InterlockedCompareExchange().
* Makefile: Likewise.
2004-09-27 Ross Johnson <rpj at callisto.canberra.edu.au>
* pthread_mutex_lock.c (pthread_mutex_lock): Separate
PTHREAD_MUTEX_NORMAL logic since we do not need to keep or check some
state required by other mutex types; do not check mutex pointer arg
for validity - leave this to the system since we are only checking
for NULL pointers. This should improve speed of NORMAL mutexes and
marginally improve speed of other type.
* pthread_mutex_trylock.c (pthread_mutex_trylock): Likewise.
* pthread_mutex_unlock.c (pthread_mutex_unlock): Likewise; also avoid
entering the critical section for the no-waiters case, with approx.
30% reduction in lock/unlock overhead for this case.
* pthread_mutex_timedlock.c (pthread_mutex_timedlock): Likewise; also
no longer keeps mutex if post-timeout second attempt succeeds - this
will assist applications that wish to impose strict lock deadlines,
rather than simply to escape from frozen locks.
2004-09-09 Tristan Savatier <tristan at mpegtv.com>
* pthread.h (struct pthread_once_t_): Qualify the 'done' element
as 'volatile'.
* pthread_once.c: Concerned about possible race condition,
specifically on MPU systems re concurrent access to multibyte types.
[Maintainer's note: the race condition is harmless on SPU systems
and only a problem on MPU systems if concurrent access results in an
exception (presumably generated by a hardware interrupt). There are
other instances of similar harmless race conditions that have not
been identified as issues.]
2004-09-09 Ross Johnson <rpj at callisto.canberra.edu.au>
* pthread.h: Declare additional types as volatile.
2004-08-27 Ross Johnson <rpj at callisto.canberra.edu.au>
* pthread_barrier_wait.c (pthread_barrier_wait): Remove excessive code
by substituting the internal non-cancelable version of sem_wait
(ptw32_semwait).
2004-08-25 Ross Johnson <rpj at callisto.canberra.edu.au>
* pthread_join.c (pthread_join): Rewrite and re-order the conditional
tests in an attempt to improve efficiency and remove a race
condition.
2004-08-23 Ross Johnson <rpj at callisto.canberra.edu.au>
* create.c (pthread_create): Don't create a thread if the thread
id pointer location (first arg) is inaccessible. A memory
protection fault will result if the thread id arg isn't an accessible
location. This is consistent with GNU/Linux but different to
Solaris or MKS (and possibly others), which accept NULL as meaning
'don't return the created thread's ID'. Applications that run
using pthreads-win32 will run on all other POSIX threads
implementations, at least w.r.t. this feature.
It was decided not to copy the Solaris et al behaviour because,
although it would have simplified some application porting (but only
from Solaris to Windows), the feature is not technically necessary,
and the alternative segfault behaviour helps avoid buggy application
code.
2004-07-01 Anuj Goyal <anuj.goyal at gmail.com>
* builddmc.bat: New; Windows bat file to build the library.
* config.h (__DMC__): Support for Digital Mars compiler.
* create.c (__DMC__): Likewise.
* pthread_exit.c (__DMC__): Likewise.
* pthread_join.c (__DMC__): Likewise.
* ptw32_threadDestroy.c (__DMC__): Likewise.
* ptw32_threadStart.c (__DMC__): Likewise.
* ptw32_throw.c (__DMC__): Likewise.
2004-06-29 Anuj Goyal <anuj.goyal at gmail.com>
* pthread.h (__DMC__): Initial support for Digital Mars compiler.
2004-06-29 Will Bryant <will.bryant at ecosm.com>
* README.Borland: New; description of Borland changes.
* Bmakefile: New makefile for the Borland make utility.
* ptw32_InterlockedCompareExchange.c:
Add Borland compatible asm code.
2004-06-26 Jason Bard <BardJA at Npt.NUWC.Navy.Mil>
* pthread.h (HAVE_STRUCT_TIMESPEC): If undefined, define it
to avoid timespec struct redefined errors elsewhere in an
application.
2004-06-21 Ross Johnson <rpj at callisto.canberra.edu.au>
* pthread.h (PTHREAD_RECURSIVE_MUTEX_INITIALIZER): Mutex
initialiser added for compatibility with Linux threads and
others; currently not included in SUSV3.
* pthread.h (PTHREAD_ERRORCHECK_MUTEX_INITIALIZER): Likewise.
* pthread.h (PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP): Likewise.
* pthread.h (PTHREAD_ERRORCHECK_MUTEX_INITIALIZER_NP): Likewise.
* ptw32_mutex_check_need_init.c (ptw32_mutex_check_need_init):
Add new initialisers.
* pthread_mutex_lock.c (pthread_mutex_lock): Check for new
initialisers.
* pthread_mutex_trylock.c (pthread_mutex_trylock): Likewise.
* pthread_mutex_timedlock.c (pthread_mutex_timedlock): Likewise.
* pthread_mutex_unlock.c (pthread_mutex_unlock): Likewise.
* pthread_mutex_destroy.c (pthread_mutex_destroy): Likewise.
2004-05-20 Ross Johnson <rpj at callisto.canberra.edu.au>
* README.NONPORTABLE: Document pthread_win32_test_features_np().
* FAQ: Update various answers.
2004-05-19 Ross Johnson <rpj at callisto.canberra.edu.au>
* Makefile: Don't define _WIN32_WINNT on compiler command line.
* GNUmakefile: Likewise.
2004-05-16 Ross Johnson <rpj at callisto.canberra.edu.au>
* pthread_cancel.c (pthread_cancel): Adapted to use auto-detected
QueueUserAPCEx features at run-time.
(ptw32_RegisterCancelation): Drop in replacement for QueueUserAPCEx()
if it can't be used. Provides older style non-preemptive async
cancelation.
* pthread_win32_attach_detach_np.c (pthread_win32_attach_np):
Auto-detect quserex.dll and the availability of alertdrv.sys;
initialise and close on process attach/detach.
* global.c (ptw32_register_cancelation): Pointer to either
QueueUserAPCEx() or ptw32_RegisterCancelation() depending on
availability. QueueUserAPCEx makes pre-emptive async cancelation
possible.
* implement.h: Add definitions and prototypes related to QueueUserAPC.
2004-05-16 Panagiotis E. Hadjidoukas <peh at hpclab.ceid.upatras.gr>
* QueueUserAPCEx (separate contributed package): Provides preemptive
APC feature.
* pthread_cancel.c (pthread_cancel): Initial integration of
QueueUserAPCEx into pthreads-win32 to provide true pre-emptive
async cancelation of threads, including blocked threads.
2004-05-06 Makoto Kato <raven at oldskool.jp>
* pthread.h (DWORD_PTR): Define typedef for older MSVC.
* pthread_cancel.c (AMD64): Add architecture specific Context register.
* ptw32_getprocessors.c: Use correct types (DWORD_PTR) for mask
variables.
2004-04-06 P. van Bruggen <pietvb at newbridges.nl>
* ptw32_threadDestroy.c: Destroy threadLock mutex to
close a memory leak.
2004-02-13 Gustav Hallberg <gustav at virtutech.com>
* pthread_equal.c: Remove redundant equality logic.
2003-12-10 Philippe Di Cristo <philipped at voicebox.com>
* sem_timedwait.c (sem_timedwait): Fix timeout calculations.
2003-10-20 Alexander Terekhov <TEREKHOV at de.ibm.com>
* pthread_mutex_timedlock.c (ptw32_semwait): Move to individual module.
* ptw32_semwait.c: New module.
* pthread_cond_wait.c (ptw32_cond_wait_cleanup): Replace cancelable
sem_wait() call with non-cancelable ptw32_semwait() call.
* pthread.c (private.c): Re-order for inlining. GNU C warned that
function ptw32_semwait() was defined 'inline' after it was called.
* pthread_cond_signal.c (ptw32_cond_unblock): Likewise.
* pthread_delay_np.c: Disable Watcom warning with comment.
* *.c (process.h): Remove include from .c files. This is conditionally
included by the common project include files.
2003-10-20 James Ewing <james.ewing at sveasoft.com>
* ptw32_getprocessors.c: Some Win32 environments don't have
GetProcessAffinityMask(), so always return CPU count = 1 for them.
* config.h (NEED_PROCESSOR_AFFINITY_MASK): Define for WinCE.
2003-10-15 Ross Johnson <ross at callisto.canberra.edu.au>
* Re-indented all .c files using default GNU style to remove assorted
editor ugliness (used GNU indent utility in default style).
2003-10-15 Alex Blanco <Alex.Blanco at motorola.com>
* sem_init.c (sem_init): Would call CreateSemaphore even if the sema
struct calloc failed; was not freeing calloced memory if either
CreateSemaphore or CreateEvent failed.
2003-10-14 Ross Johnson <ross at callisto.canberra.edu.au>
* pthread.h: Add Watcom compiler compatibility. Esssentially just add
the cdecl attribute to all exposed function prototypes so that Watcom
generates function call code compatible with non-Watcom built libraries.
By default, Watcom uses registers to pass function args if possible rather
than pushing to stack.
* semaphore.h: Likewise.
* sched.h: Likewise.
* pthread_cond_wait.c (ptw32_cond_wait_cleanup): Define with cdecl attribute
for Watcom compatibility. This routine is called via pthread_cleanup_push so
it had to match function arg definition.
* Wmakefile: New makefile for Watcom builds.
2003-09-14 Ross Johnson <rpj at callisto.canberra.edu.au>
* pthread_setschedparam.c (pthread_setschedparam): Attempt to map
all priority levels between max and min (as returned by
sched_get_priority_min/max) to reasonable Win32 priority levels - i.e.
levels between THREAD_PRIORITY_LOWEST/IDLE to THREAD_PRIORITY_LOWEST and
between THREAD_PRIORITY_HIGHEST/TIME_CRITICAL to THREAD_PRIORITY_HIGHEST
while others remain unchanged; record specified thread priority level
for return by pthread_getschedparam.
Note that, previously, specified levels not matching Win32 priority levels
would silently leave the current thread priority unaltered.
* pthread_getschedparam.c (pthread_getschedparam): Return the priority
level specified by the latest pthread_setschedparam or pthread_create rather
than the actual running thread priority as returned by GetThreadPriority - as
required by POSIX. I.e. temporary or adjusted actual priority levels are not
returned by this routine.
* pthread_create.c (pthread_create): For priority levels specified via
pthread attributes, attempt to map all priority levels between max and
min (as returned by sched_get_priority_min/max) to reasonable Win32
priority levels; record priority level given via attributes, or
inherited from parent thread, for later return by pthread_getschedparam.
* ptw32_new.c (ptw32_new): Initialise pthread_t_ sched_priority element.
* pthread_self.c (pthread_self): Set newly created implicit POSIX thread
sched_priority to Win32 thread's current actual priority. Temporarily
altered priorities can't be avoided in this case.
* implement.h (struct pthread_t_): Add new sched_priority element.
2003-09-12 Ross Johnson <rpj at callisto.canberra.edu.au>
* sched_get_priority_min.c (sched_get_priority_min): On error should return -1
with errno set.
* sched_get_priority_max.c (sched_get_priority_max): Likewise.
2003-09-03 Ross Johnson <rpj at callisto.canberra.edu.au>
* w32_cancelableWait.c (ptw32_cancelable_wait): Allow cancelation
of implicit POSIX threads as well.
2003-09-02 Ross Johnson <rpj at callisto.canberra.edu.au>
* pthread_win32_attach_detach_np.c (pthread_win32_thread_detach_np):
Add comment.
* pthread_exit.c (pthread_exit): Fix to recycle the POSIX thread handle in
addition to calling user TSD destructors. Move the implicit POSIX thread exit
handling to ptw32_throw to centralise the logic.
* ptw32_throw.c (ptw32_throw): Implicit POSIX threads have no point
to jump or throw to, so cleanup and exit the thread here in this case. For
processes using the C runtime, the exit code will be set to the POSIX
reason for the throw (i.e. PTHREAD_CANCEL or the value given to pthread_exit).
Note that pthread_exit() already had similar logic, which has been moved to
here.
* ptw32_threadDestroy.c (ptw32_threadDestroy): Don't close the Win32 handle
of implicit POSIX threads - expect this to be done by Win32?
2003-09-01 Ross Johnson <rpj at callisto.canberra.edu.au>
* pthread_self.c (pthread_self): The newly aquired pthread_t must be
assigned to the reuse stack, not freed, if the routine fails somehow.
2003-08-13 Ross Johnson <rpj at ise.canberra.edu.au>
* pthread_getschedparam.c (pthread_getschedparam): An invalid thread ID
parameter was returning an incorrect error value; now uses a more exhaustive
check for validity.
* pthread_setschedparam.c (pthread_setschedparam): Likewise.
* pthread_join.c (pthread_join): Now uses a more exhaustive
check for validity.
* pthread_detach.c (pthread_detach): Likewise.
* pthread_cancel.c (pthread_cancel): Likewise.
* ptw32_threadDestroy.c (ptw32_threadDestroy): pthread_t structs are
never freed - push them onto a stack for reuse.
* ptw32_new.c (ptw32_new): Check for reusable pthread_t before dynamically
allocating new memory for the struct.
* pthread_kill.c (pthread_kill): New file; new routine; takes only a zero
signal arg so that applications can check the thread arg for validity; checks
that the underlying Win32 thread HANDLE is valid.
* pthread.h (pthread_kill): Add prototype.
* ptw32_reuse.c (ptw32_threadReusePop): New file; new routine; pop a
pthread_t off the reuse stack. pthread_t_ structs that have been destroyed, i.e.
have exited detached or have been joined, are cleaned up and put onto a reuse
stack. Consequently, thread IDs are no longer freed once calloced. The library
will attempt to get a struct off this stack before asking the system to alloc
new memory when creating threads. The stack is guarded by a global mutex.
(ptw32_threadReusePush): New routine; push a pthread_t onto the reuse stack.
* implement.h (ptw32_threadReusePush): Add new prototype.
(ptw32_threadReusePop): Likewise.
(pthread_t): Add new element.
* ptw32_processTerminate.c (ptw32_processTerminate): Delete the thread
reuse lock; free all thread ID structs on the thread reuse stack.
* ptw32_processInitialize.c (ptw32_processInitialize): Initialise the
thread reuse lock.
2003-07-19 Ross Johnson <rpj at ise.canberra.edu.au>
* GNUmakefile: modified to work under MsysDTK environment.
* pthread_spin_lock.c (pthread_spin_lock): Check for NULL arg.
* pthread_spin_unlock.c (pthread_spin_unlock): Likewise.
* pthread_spin_trylock.c (pthread_spin_trylock): Likewise;
fix incorrect pointer value if lock is dynamically initialised by
this function.
* sem_init.c (sem_init): Initialise sem_t value to quell compiler warning.
* sem_destroy.c (sem_destroy): Likewise.
* ptw32_threadStart.c (non-MSVC code sections): Include <exception> rather
than old-style <new.h>; fix all std:: namespace entities such as
std::terminate_handler instances and associated methods.
* ptw32_callUserDestroyRoutines.c (non-MSVC code sections): Likewise.
2003-06-24 Piet van Bruggen <pietvb at newbridges.nl>
* pthread_spin_destroy.c (pthread_spin_destroy): Was not freeing the
spinlock struct.
2003-06-22 Nicolas Barry <boozai at yahoo.com>
* pthread_mutex_destroy.c (pthread_mutex_destroy): When called
with a recursive mutex that was locked by the current thread, the
function was failing with a success return code.
2003-05-15 Steven Reddie <Steven.Reddie at ca.com>
* pthread_win32_attach_detach_np.c (pthread_win32_process_detach_np):
NULLify ptw32_selfThreadKey after the thread is destroyed, otherwise
destructors calling pthreads routines might resurrect it again, creating
memory leaks. Call the underlying Win32 Tls routine directly rather than
pthread_setspecific().
(pthread_win32_thread_detach_np): Likewise.
2003-05-14 Viv <vcotirlea at hotmail.com>
* pthread.dsp: Change /MT compile flag to /MD.
2003-03-04 Alexander Terekhov <TEREKHOV at de.ibm.com>
* pthread_mutex_timedlock.c (pthread_mutex_timedlock): Fix failure to
set ownership of mutex on second grab after abstime timeout.
- bug reported by Robert Strycek <strycek at posam.sk>
2002-12-17 Thomas Pfaff <tpfaff at gmx.net>
* pthread_mutex_lock.c (ptw32_semwait): New static routine to provide
a non-cancelable sem_wait() function. This is consistent with the
way that pthread_mutex_timedlock.c does it.
(pthread_mutex_lock): Use ptw32_semwait() instead of sem_wait().
2002-12-11 Thomas Pfaff <tpfaff at gmx.net>
* pthread_mutex_trylock.c: Should return EBUSY rather than EDEADLK.
* pthread_mutex_destroy.c: Remove redundant ownership test (the
trylock call does this for us); do not destroy a recursively locked
mutex.
2002-09-20 Michael Johnson <michaelj at maine.rr.com>
* pthread_cond_destroy.c (pthread_cond_destroy):
When two different threads exist, and one is attempting to
destroy a condition variable while the other is attempting to
initialize a condition variable that was created with
PTHREAD_COND_INITIALIZER, a deadlock can occur. Shrink
the ptw32_cond_list_lock critical section to fix it.
2002-07-31 Ross Johnson <rpj at special.ise.canberra.edu.au>
* ptw32_threadStart.c (ptw32_threadStart): Thread cancelLock
destruction moved to ptw32_threadDestroy().
* ptw32_threadDestroy.c (ptw32_threadDestroy): Destroy
the thread's cancelLock. Moved here from ptw32_threadStart.c
to cleanup implicit threads as well.
2002-07-30 Alexander Terekhov <TEREKHOV at de.ibm.com>
* pthread_cond_wait.c (ptw32_cond_wait_cleanup):
Remove code designed to avoid/prevent spurious wakeup
problems. It is believed that the sem_timedwait() call
is consuming a CV signal that it shouldn't and this is
breaking the avoidance logic.
2002-07-30 Ross Johnson <rpj at ise.canberra.edu.au>
* sem_timedwait.c (sem_timedwait): Tighten checks for
unreasonable abstime values - that would result in
unexpected timeout values.
* w32_CancelableWait.c (ptw32_cancelable_wait):
Tighten up return value checking and add comments.
2002-06-08 Ross Johnson <rpj at special.ise.canberra.edu.au>
* sem_getvalue.c (sem_getvalue): Now returns a value for the
NEED_SEM version (i.e. earlier versions of WinCE).
2002-06-04 Rob Fanner <rfanner at stonethree.com>
* sem_getvalue.c (sem_getvalue): The Johnson M. Hart
approach didn't work - we are forced to take an
intrusive approach. We try to decrement the sema
and then immediately release it again to get the
value. There is a small probability that this may
block other threads, but only momentarily.
2002-06-03 Ross Johnson <rpj at ise.canberra.edu.au>