Commit Graph

387 Commits

Author SHA1 Message Date
David Xu
a8a343d2e6 _thr_ucond_wait drops lock, we should pick it up again. 2006-12-05 23:46:11 +00:00
David Xu
3b8a017442 the c_has_waiters is lazily updated, temporarily disable the false
alarm code.
2006-12-05 07:23:58 +00:00
David Xu
4d617f2d10 Use ucond to implement barrier. 2006-12-05 06:54:25 +00:00
David Xu
670b44d65a Add _thr_ucond_init(). 2006-12-05 06:53:44 +00:00
David Xu
3ce4e91d4e Tweak _thr_cancel_leave_defer a bit to fix a possible race. 2006-12-05 05:01:57 +00:00
David Xu
3c61d00ab6 Fix typo, I was using a wrong header file, and the typo is not detected
by compiler.
2006-12-04 14:27:42 +00:00
David Xu
2bd2c90703 Use kernel provided userspace condition variable to implement pthread
condition variable.
2006-12-04 14:20:41 +00:00
David Xu
6f54e82927 If a thread was detached, return EINVAL instead, the error code
is also returned by pthread_detach() if a thread was already
detached, the error code was already documented:

>    [EINVAL]	The implementation has detected that the value speci-
>		fied by thread does not refer to a joinable thread.
2006-11-28 11:05:31 +00:00
Ruslan Ermilov
8af480aec1 - When building world WITHOUT_LIBPTHREAD, link libthr to libpthread.
- Don't build ngctl(8) and cached(8) if threading libs aren't built.
- Fix various issues in a cached(8) makefile.
2006-11-26 14:36:34 +00:00
David Xu
f08e1bf682 Eliminate atomic operations in thread cancellation functions, it should
reduce overheads of cancellation points.
2006-11-24 09:57:38 +00:00
David Xu
58c7bab332 Move code calculating new inherited priority into single function. 2006-11-11 13:33:47 +00:00
David Xu
5656b5fafa Don't inherit THR_FLAGS_NEED_SUSPEND for child process, child process
only has one thread, setting the flag can cause the thread to be
suspended and no another thread will resume it.
2006-10-14 13:40:08 +00:00
David Xu
8042f26d52 o Make _thr_umutex_init a function.
o Eliminate unused parameter for some functions.
o Convert type of first parameter to void * for _thr_umtx_wait
  and _thr_umtx_wake.
2006-10-13 22:31:00 +00:00
David Xu
0b90fa4ad0 Use type pthread_state for thread state. 2006-10-13 12:45:21 +00:00
David Xu
e6747c7ce1 use rtprio_thread system call to get or set thread priority. 2006-09-21 04:21:30 +00:00
David Xu
ddaf6689e3 Use return value of _thr_umutex_lock instead of using zero. 2006-09-08 09:29:14 +00:00
David Xu
bddd24cd9c Replace internal usage of struct umtx with umutex which can supports
real-time if we want, no functionality is changed.
2006-09-06 04:04:10 +00:00
David Xu
8549079365 Same as pthread_setschedparam, use sizeof(struct sched_param) instead. 2006-09-05 14:39:06 +00:00
David Xu
be0bfdd207 Pass correct parameter size. 2006-09-05 14:37:22 +00:00
Marcel Moolenaar
be2f4bda88 Stylize: avoid using a global register variable. 2006-09-01 21:01:11 +00:00
Marcel Moolenaar
cc79b334de Rename TLS_TP_OFFSET back to TP_OFFSET. The former clashes with rtld. 2006-09-01 06:36:00 +00:00
Marcel Moolenaar
8e61dbecfc Stylize. 2006-09-01 06:15:00 +00:00
Marcel Moolenaar
35ca217bf0 Stylize. 2006-08-31 23:31:18 +00:00
Marcel Moolenaar
9f7b8b0d3c TLS fixes:
o  The TLS pointer (r2) points 0x7000 after the *end* of the TCB.
o  _rtld_allocate_tls() gets a pointer to the current TCB, not the
   current TLS pointer.
o  _rtld_free_tls() gets the size of the TCB structure.
2006-08-31 19:16:47 +00:00
Marcel Moolenaar
91705de0c2 Fix harmless bug: sizeof(tcb) equals sizeof(void*) not sizeof(struct tcb).
The argument is (currently) not used by _rtld_free_tls().
2006-08-31 19:06:30 +00:00
Marcel Moolenaar
57c2251d5c o Set TP using inline assembly to avoid dead code elimination.
o  Eliminate _tcb.
2006-08-30 03:31:32 +00:00
David Xu
fd2b89c48c Remove unused file. 2006-08-29 13:01:23 +00:00
David Xu
215318a7a3 pthread_sigmask is in thr_sig.c, remove this file. 2006-08-28 12:29:54 +00:00
David Xu
6361212beb Kill unused files. 2006-08-28 05:01:31 +00:00
David Xu
8ab9d78b9d Use umutex APIs to implement pthread_mutex, member pp_mutexq is added
into pthread structure to keep track of locked PTHREAD_PRIO_PROTECT mutex,
no real mutex code is changed, the mutex locking and unlocking code should
has same performance as before.
2006-08-28 04:52:50 +00:00
David Xu
cf13ecda6a Add umutex APIs. 2006-08-28 04:47:27 +00:00
Ruslan Ermilov
2b46c64c9c Remove alpha left-overs. 2006-08-22 08:03:01 +00:00
David Xu
065dbdc130 Axe unused member field. 2006-08-08 05:04:43 +00:00
David Xu
6b73f08519 Get number of CPUs and ignore spin count on single processor machine. 2006-08-08 04:42:41 +00:00
David Xu
05c3a5eab4 1. Don't override underscore version of aio_suspend(), system(),
wait(), waitpid() and usleep(), they are internal versions and
   should not be cancellation points.
2. Make wait3() as a cancellation point.
3. Move raise() and pause() into file thr_sig.c.
4. Add functions _sigsuspend, _sigwait, _sigtimedwait and _sigwaitinfo,
   remove SIGCANCEL bit in wait-set for those functions, the signal is
   used internally to implement thread cancellation.
2006-07-25 12:50:05 +00:00
Xin LI
da84584390 Unexpand two TAILQ_FOREACH_SAFE cases.
Ok'ed by:	davidxu
2006-07-17 09:23:44 +00:00
David Xu
e2dc286c1c Caching scheduling policy and priority in userland, a critical but baddly
written application is frequently changing thread priority for SCHED_OTHER
policy.
2006-07-13 22:45:19 +00:00
David Xu
561a89f945 Use thr_setscheduler, thr_getscheduler and thr_setschedparam to implement
pthread functions.
2006-07-13 06:35:43 +00:00
David Xu
7b4f8f037f Use kernel facilities to support real-time scheduling. 2006-07-12 06:13:18 +00:00
David Xu
9bbc6c7f54 __error could be called too early before libthr is initialized, test
this case and return global varible errno instead.
2006-07-12 03:44:05 +00:00
David Xu
7fabe0b5cc Remove unused member. 2006-06-03 00:19:40 +00:00
David Xu
b971a73040 Remove unused member field m_queue. 2006-06-02 08:37:01 +00:00
Xin LI
631574e7dc Explicitly request pre-zeroed memory instead of memset'ing our
own.

Ok'ed by:	davidxu
2006-05-31 00:31:38 +00:00
David Xu
e92b415c5a Add symbol versions: FBSD_1.0 and FBSDprivate. 2006-05-11 07:02:52 +00:00
David Xu
0a5fa45560 s/long/int. 2006-04-27 08:25:13 +00:00
David Xu
245116cafc - Use same priority range returned by kernel's sched_get_priority_min()
and sched_get_priority_max() syscalls.
- Remove unused fields from structure pthread_attr.
2006-04-27 08:18:23 +00:00
David Xu
d96413eaa4 Remove multiple _get_curthread() calls. 2006-04-23 11:23:37 +00:00
Ruslan Ermilov
84e709f1f1 Install shared libpthread library into /lib; needed by some
/sbin programs.
2006-04-12 19:42:20 +00:00
David Xu
a97944597b Do not check validity of timeout if a mutex can be acquired immediately.
Completly drop recursive mutex in pthread_cond_wait and restore recursive
after resumption. Reorganize code to make gcc to generate better code.
2006-04-08 13:24:44 +00:00
David Xu
b7e118b1e0 Remove declaration of _thr_initial from MD header file, it is no longer
needed.
2006-04-04 03:35:26 +00:00
David Xu
7bd761788d Simplify _get_curthread() and _tcb_ctor because libc and rtld now
already allocate thread pointer space in tls block for initial thread.
Only i386 and amd64 have been done, others still have to be tested.
2006-04-04 03:26:06 +00:00
David Xu
37a6356bbe WARNS level 4 cleanup. 2006-04-04 02:57:49 +00:00
Dag-Erling Smørgrav
552585665b Fix prototype mismatch. 2006-03-28 21:46:55 +00:00
David Xu
9ad4b64459 Remove priority mutex code because it does not work correctly,
to make it work, turnstile like mechanism to support priority
propagating and other realtime scheduling options in kernel
should be available to userland mutex, for the moment, I just
want to make libthr be simple and efficient thread library.

Discussed with: deischen, julian
2006-03-27 23:50:21 +00:00
David Xu
649814dd6c Comment out -g compiler option, found by 'FreeBSD Build Options Survey'. 2006-03-27 05:58:58 +00:00
David Xu
d448272d3c Check cancellation state carefully to see we really need to call
_pthread_testcancel(). Preserve errno in _thr_suspend_check().
2006-03-26 01:57:03 +00:00
David Xu
efe33769b9 Don't cancel thread if it is in critical region. 2006-03-25 07:03:13 +00:00
David Xu
f656ae703e Only wake up writer if the lock is free. 2006-03-25 05:14:21 +00:00
David Xu
07c7c80074 Compile thr_rtld.c 2006-03-25 05:00:54 +00:00
David Xu
b6b894f66b Add locking support for rtld. 2006-03-25 04:49:07 +00:00
David Xu
c147998f53 set an upper limit for thread structures which can be allocated. 2006-03-24 04:34:06 +00:00
David Xu
6f79c82641 Set default contention scope to system. 2006-03-20 03:14:14 +00:00
Ruslan Ermilov
5740a2b62d Convert NO_PROFILE and NO_LIB32 to new style. 2006-03-18 21:37:05 +00:00
David Xu
d3de1dcae7 Remove mqueue and timer, now they are in librt. 2006-03-08 23:47:04 +00:00
Daniel Eischen
f4cd2a5b5c Add some more pthread stubs so that librt can use them.
The thread jump table has been resorted, so you need to
keep libc, libpthread, and libthr in sync.

Submitted by:	xu
2006-03-05 18:10:28 +00:00
David Xu
7b8797d300 Reimplement mutex_init to get rid of compile warning. 2006-02-28 06:06:19 +00:00
David Xu
b620798174 Disable POSIX SIGEV_THREAD notification support, soon we will have a common
library which can be reused both for libthr and libpthread.
2006-02-22 02:52:22 +00:00
David Xu
bab012a948 Read cycle count before sending signal, this fixes a userland thread
suspension bug.

MFC after: 3 days
2006-02-20 09:02:40 +00:00
David Xu
6f716c2f82 Rework last change of pthread_once, create a function _thr_once_init to
reinitialize its internal locks.
2006-02-15 23:05:03 +00:00
David Xu
c5d2fb8df7 After fork(), reinitialize internal locks for pthread_once(). 2006-02-15 13:41:02 +00:00
David Xu
8956297a57 Now, thread name is stored in kernel, userland no longer has to keep it. 2006-02-05 03:04:54 +00:00
David Xu
3f7dda33b7 use syscall thr_set_name to implement pthread_set_name_np. 2006-02-05 02:26:17 +00:00
David Xu
5f9df00649 Add missing symbol pthread_set_name_np. 2006-01-23 06:11:23 +00:00
David Xu
1c9db39d88 Eliminate unused code. 2006-01-16 05:33:48 +00:00
David Xu
add2da0db1 Enable mutex inheritance code in mutex_fork, I forgot to turn on it.
while here, add some comments about process shared mutex.
2006-01-14 11:33:43 +00:00
Jason Evans
90dc795234 Increase the number of spinlocks, since libc's malloc implementation is
about to significantly increase the number of spinlocks used.

Approved by:	markm (mentor)
2006-01-13 06:14:04 +00:00
Jason Evans
52828c0e9c In preparation for a new malloc implementation:
* Add posix_memalign().

  * Move calloc() from calloc.c to malloc.c.  Add a calloc() implementation in
    rtld-elf in order to make the loader happy (even though calloc() isn't
    used in rtld-elf).

  * Add _malloc_prefork() and _malloc_postfork(), and use them instead of
    directly manipulating __malloc_lock.

Approved by:	phk, markm (mentor)
2006-01-12 07:28:21 +00:00
David Xu
07a263153e The thr_new sysscall was already in libc, don't generate it. 2006-01-11 06:10:05 +00:00
David Xu
9572a73405 Use macro STATIC_LIB_REQUIRE to declare a symbol should be linked into
static binary.
2006-01-10 04:53:03 +00:00
David Xu
e35e2ebd24 Rescue pthread_set_name_np for compatible reason, remove unused code. 2006-01-09 08:07:22 +00:00
David Xu
a53747d8fe Tweak macro THR_LOCK_RELEASE a bit for non-PTHREAD_INVARIANTS case. 2006-01-09 07:32:22 +00:00
David Xu
4160cda0dc Return real detached state. 2006-01-09 03:59:51 +00:00
David Xu
1775714935 Fix a bug recently introduced, the _thread_active_count should be
decreased if thread can not be created.
2006-01-08 10:13:18 +00:00
David Xu
23db0a33f7 Allow background threads to be suspended. 2006-01-08 01:49:31 +00:00
David Xu
0d29c148eb Try to reduce total time needed for suspending all threads,
first broadcast signals to all threads, then enter a wait loop.
2006-01-08 01:48:51 +00:00
David Xu
d827aa478d Remove functions i386_get_gsbase and i386_set_gsbase, they were already
in libc.
2006-01-07 06:01:43 +00:00
David Xu
bc414752d3 Refine thread suspension code, now thread suspension is a blockable
operation, the caller is blocked util target threads are really
suspended, also avoid suspending a thread when it is holding a
critical lock.
Fix a bug in _thr_ref_delete which tests a never set flag.
2006-01-05 13:51:22 +00:00
David Xu
5131df80a5 1. Add SIGEV_THREAD notification for mq_notify.
2. Reuse current timer code and abstract some common code to
   to support both timer and mqueue.
2006-01-04 11:48:02 +00:00
David Xu
97986a2ea0 Remove in-progress wait code to sync with libpthread's behavior. 2006-01-03 13:30:23 +00:00
David Xu
e6262545cf Let _mutex_cv_lock call internal functiona mutex_lock_common. 2005-12-21 05:14:07 +00:00
David Xu
8429e73473 Hide umtx API symbols as well. 2005-12-21 03:53:29 +00:00
David Xu
cf905a1575 1. Retire macro SCLASS, instead simply use language keyword and
put variables in thr_init.c.
2. Hide all global symbols which won't be exported.
2005-12-21 03:14:06 +00:00
David Xu
7a65760923 Follow the mistake in libpthread, the first version name in libpthread
is LIBTHREAD_1_0, but really it should be LIBPTHREAD_1_0.
Fix it so libmap.conf works again (it was broken by recent versioning
code in rtld_elf).
2005-12-21 02:34:20 +00:00
David Xu
597dc824a0 Clear return code to zero if joiner successfully waited joinee.
Bug reported by: jasone at connonware when using ports lang/onyx
MFC after: 3 days
2005-12-19 03:20:55 +00:00
David Xu
df2cf82178 Update copyright. 2005-12-17 09:42:45 +00:00
David Xu
e6a9baa280 Remove unused _get_curthread() call. 2005-12-12 07:14:57 +00:00
David Xu
8f0371f19d Fix name compatible problem with POSIX standard. the sigval_ptr and
sigval_int really should be sival_ptr and sival_int.
Also sigev_notify_function accepts a union sigval value but not a
pointer.
2005-11-04 09:41:00 +00:00
David Xu
e89510b152 Remove a redundant _get_curthread() call. 2005-11-02 14:06:29 +00:00
David Xu
7f838bf429 In raise(), use a shortcut to directly send signal to current thread. 2005-11-02 13:52:48 +00:00
David Xu
bff49d66ab Fix some comments, eliminate a memory leak. 2005-11-01 13:05:47 +00:00
David Xu
6cae59b1e7 Use TIMERS_UNLOCK. 2005-11-01 07:05:32 +00:00
David Xu
53bbdf8646 Add code to handle timer_delete(). The timer wrapper code is completely
rewritten, now timers created with same sigev_notify_attributes will
run in same thread, this allows user to organize which timers can
run in same thread to save some thread resource.
2005-11-01 06:53:22 +00:00
David Xu
7a81302ce7 Add thread exit handler in timer_loop to handle broken buggy code which
could lead to memory leak.
2005-10-30 23:59:01 +00:00
David Xu
4a050d016e Add timer_create wrapper. 2005-10-30 03:16:30 +00:00
David Xu
c09df63bb9 Remove unused variable.
Reviewed by: cognet
2005-10-29 13:40:31 +00:00
David Xu
babdcc8d78 Kill unused variable declaration. 2005-10-29 03:08:43 +00:00
David Xu
55ac4c3523 Link libthr to libpthread on Alpha and Sparc. 2005-10-27 10:21:23 +00:00
David Xu
07b6889426 Add experiment code to implement POSIX timer's SIGEV_THREAD notification. 2005-10-26 11:08:32 +00:00
David Xu
d7f119abd5 Follow the change in kernel, joiner thread just waits at thread id
address, let kernel wake it up.
2005-10-26 07:11:43 +00:00
David Xu
9fc171584d Put pthread_condattr_init sorted order. 2005-10-25 00:09:58 +00:00
David Xu
7dcb6ea4f6 Export following functions:
_pthread_mutexattr_getpshared
	_pthread_mutexattr_setpshared
	pthread_condattr_getpshared
	pthread_condattr_setpshared
	pthread_mutexattr_getpshared
	pthread_mutexattr_setpshared
2005-10-24 05:20:04 +00:00
David Xu
c3d1b896b2 Add functions pthread_mutexattr_setpshared and pthread_mutexattr_getpshared. 2005-10-24 05:16:41 +00:00
David Xu
88676cbc2c The pthread_attr_set_createsuspend_np was broken, fix it by
replacing THR_FLAGS_SUSPENDED with THR_FLAGS_NEED_SUSPEND.
2005-10-10 12:15:07 +00:00
David Xu
d1f3c70b6e Sort function names. 2005-10-04 08:28:46 +00:00
David Xu
9e49a2370c Add function pthread_timedjoin_np, the function is similar with pthread_join
except the function will return ETIMEDOUT if target thread does not exit
before specified absolute time passes.
2005-10-04 06:15:25 +00:00
Stefan Farfeleder
7e4cbc3a50 Include needed headers that were obtained through <pthread.h>. Sort headers
while here.
2005-09-01 15:21:23 +00:00
Stefan Farfeleder
ad7c49168f - Prefix MUTEX_TYPE_MAX with PTHREAD_ to avoid namespace pollution.
- Remove the macros MUTEX_TYPE_FAST and MUTEX_TYPE_COUNTING_FAST.

OK'ed by:	deischen
2005-08-19 21:31:42 +00:00
Daniel Eischen
2ce2892eaf Add usleep to the map files.
Noticed by:	davidxu
2005-08-03 01:54:52 +00:00
Daniel Eischen
14d5987375 Add a cancellation point for usleep().
While here, fix sleep() so that it is also a cancellation point (a
missing weak reference prevented that).
2005-08-03 00:47:31 +00:00
David Xu
2ff77b9220 Cast to uintptr_t to avoid compiler warning, it was broken by
the recent atomic_ptr() change.
2005-07-28 03:34:54 +00:00
Ken Smith
a84020c2b9 Bump the shared library version number of all libraries that have not
been bumped since RELENG_5.

Reviewed by:	ru
Approved by:	re (not needed for commit check but in principle...)
2005-07-22 17:19:05 +00:00
David Xu
3adc17c503 Fix off-by-one nanosecond bug in macro TIMESPEC_ADD.
Reviewed by: deischen
Approved by: re (dwhite)
MFC after  : 4 days
2005-06-22 22:38:56 +00:00
Ruslan Ermilov
48856b0042 Markup fixes.
Approved by:	re
2005-06-16 19:01:07 +00:00
Robert Watson
bbc0285dc8 Remove incorrect BUGS entry: libthr does support process-scope thread
scheduling.

MFC after:	1 week
Submitted by:	davidxu
Approved by:	re (scottl)
2005-06-15 15:21:10 +00:00
Robert Watson
5335c6bc6a Add a stub libthr(3) man page to document what it is and why, as well as
to point at libmap.conf(5).  This will help answer questions about what
and why it is, although not in great detail.

Approved by:	re (scottl)
MFC after:	1 week
MFC note:	When MFC'd, don't MFC mention of work not yet MFC'd.
2005-06-11 15:27:56 +00:00
David Xu
920d31ef8d Remove COMPAT_32BIT, it is no longer needed. 2005-04-27 01:29:03 +00:00
David Xu
ff87e1a6ba Remove unused variable. 2005-04-23 03:34:43 +00:00
David Xu
a364e127e3 Now libthr only uses GDT based tls on i386. using LDT can only increase
clock cycles and has 8191 threads limitation.
2005-04-23 03:31:59 +00:00
David Xu
80c9676e8b Use thr_new syscall to create a new thread, obscure context operations
is no longer needed.
2005-04-23 02:48:59 +00:00
David Xu
3466f35a77 Add i386_get_gsbase, i386_set_gsbase since old libc doesn't have the
functions, otherwise user ports have to be rebuilt.
2005-04-23 02:14:38 +00:00
Peter Wemm
c050415d18 Adapt the libpthread patch for using i386_set_gsbase() to libthr. 2005-04-14 00:44:07 +00:00
David Xu
7a4cd8d366 Conditionally report initial thread event. 2005-04-12 03:13:49 +00:00
David Xu
4faae5e992 Add missing event reporting code. 2005-04-12 03:08:11 +00:00
David Xu
d245d9e13f Add debugger event reporting support, current only TD_CREATE and TD_DEATH
events are reported.
2005-04-12 03:00:28 +00:00
Olivier Houchard
e0d6cac076 Use the new atomic_cmpset_32(). 2005-04-07 22:06:05 +00:00
David Xu
62a2d99ce5 Adjust hash function for smaller pthread structure size. 2005-04-07 06:09:17 +00:00
David Xu
bc1eb018c1 Remove unique id field which is no longer used by debugger. 2005-04-06 13:57:31 +00:00
David Xu
02e98e495b Remove debug symbol from installed library, one can always
use compiled version in libthr directory.
2005-04-06 13:48:11 +00:00
David Xu
619f4fce79 Pass exact number of threads. 2005-04-04 23:43:53 +00:00
David Xu
fb91fbdc5d Export pthread_condattr_getclock, pthread_condattr_setclock. 2005-04-03 23:52:29 +00:00
David Xu
a091d823ad Import my recent 1:1 threading working. some features improved includes:
1. fast simple type mutex.
 2. __thread tls works.
 3. asynchronous cancellation works ( using signal ).
 4. thread synchronization is fully based on umtx, mainly, condition
    variable and other synchronization objects were rewritten by using
    umtx directly. those objects can be shared between processes via
    shared memory, it has to change ABI which does not happen yet.
 5. default stack size is increased to 1M on 32 bits platform, 2M for
    64 bits platform.
As the result, some mysql super-smack benchmarks show performance is
improved massivly.

Okayed by: jeff, mtm, rwatson, scottl
2005-04-02 01:20:00 +00:00
Joe Marcus Clarke
c5a6625e3e Increase the default stacksizes:
32-bit		64-bit
main thread	2 MB		4 MB
other threads	1 MB		2 MB

Approved by:	mtm
Adapted from:	libpthread
2005-03-06 07:56:18 +00:00
Peter Wemm
37771efde6 Fix inverted #ifdef that I added. Who had the pointy hat last?
Submitted by:  kan
2004-12-06 20:41:09 +00:00
David Schultz
6004362e66 Don't include sys/user.h merely for its side-effect of recursively
including other headers.
2004-11-27 06:51:39 +00:00
Peter Wemm
c5bfff3bab Use the recently exposed fs/gs set functions when compiling libthr to
run as a 32 bit support library for an amd64 kernel.  32 bit consumers of
libthr have zero chance of running on an amd64 kernel since we don't
implement the i386_set_ldt() family of functions.  Note that this commit
doesn't make it actually work, it just removes one more obstacle.
2004-11-06 03:30:53 +00:00
Ruslan Ermilov
a35d88931c For variables that are only checked with defined(), don't provide
any fake value.
2004-10-24 15:33:08 +00:00
Mike Makonnen
5dbd7addb0 1. Now that it's a thread's state is changed from within the kernel, where
no userland locks are heald, the dead thread lock can no longer protect
   access to it. Therefore, instead of using an if (!dead)...else clause
   after walking the active threads list test the thread pointer before
   deciding not to walk the dead threads list. If the thread pointer is null
   it means it was not found in the active threads list and the dead threads
   list should be checked.

2. Do not free the stack of a thread that is not marked dead. This is the
   2nd and final part of eliminating the race to free a thread's stack.

MFC after: 3 days
2004-10-13 11:42:20 +00:00
Mike Makonnen
4cdb7f14ed Remove a reference to a non-existent syscall: _thr_exit(). The
actual name is thr_exit(). How this ever worked is beyond me.
2004-10-08 14:48:02 +00:00
Mike Makonnen
401901ac43 Close a race between a thread exiting and the freeing of it's stack.
After some discussion the best option seems to be to signal the thread's
death from within the kernel. This requires that thr_exit() take an
argument.

Discussed with: davidxu, deischen, marcel
MFC after: 3 days
2004-10-06 14:23:00 +00:00
Mike Makonnen
2d79470f8a Remove vestiges of libthr's signal mangling past. This fixes that last
known problem with mysql on libthr: not being able to kill mysqld.
2004-09-22 18:51:16 +00:00