Commit Graph

183 Commits

Author SHA1 Message Date
Peter Wemm
7f3dea244c $Id$ -> $FreeBSD$ 1999-08-28 00:22:10 +00:00
Alfred Perlstein
89f6acf96a move sanity check of timeval struct so as not to segfault when passed
a null pointer.

Pointed out by: Thomas Gellekum <tg@ihf.rwth-aachen.de>
Reviewed by:    eivind
1999-08-20 21:06:20 +00:00
John Birrell
e4065e8294 When checking if there is a stack to free, observe the fact that it
might have been mmapped, and if so, passing the pointer to free() is
really not a good idea.

[ In the next millenium, when I've taken over the world, I'm going
  to ban 8 character tabs. You've been warned. ]
1999-08-20 12:17:09 +00:00
Alfred Perlstein
4c263f605c time_to_sleep->tv_nsec > 1000000000
-to-
time_to_sleep->tv_nsec >= 1000000000
1999-08-19 23:18:07 +00:00
Alfred Perlstein
91518882e0 Sanity check time structures passed in, return EINVAL like the system
calls do to avoid corrupting the thread library's concept of wakeup
time.

PR:		kern/12141
Reviewed by:	deischen, eivind
1999-08-19 23:06:11 +00:00
Alfred Perlstein
c81c6baf1d handle under/overflow of time values in a more robust manner,
there may be an overflow that need to be adjusted more than once.

Pointed out by: Fabian Thylmann <fthylmann@stats.net>

Reviewed by:	eivind, jb
1999-08-19 16:49:53 +00:00
Daniel Eischen
936aa6b443 Add check for runnable threads before polling file descriptors.
Submitted by:	tegge
1999-08-12 19:34:39 +00:00
Daniel Eischen
fa7c4d5575 Add RCS IDs to those files without them.
Fix copyrights (s/REGENTS/AUTHOR).

Suggested by:	tg
Approved by:	jb
1999-08-05 12:15:30 +00:00
Daniel Eischen
8b5d18ec76 Fix thread initialization to allow for the case where stdio file
descriptors are not opened.

PR:		bin/12853
Reviewed by:	jb
1999-08-05 12:08:10 +00:00
Dmitrij Tejblum
6ff19e189d Use USRSTACK (defined in <machine/vmparam.h>) to get top of the initial stack.
PTHREAD_STACK_TOP was wrong for all supported architectures.
1999-07-12 16:09:30 +00:00
Jason Evans
66da783384 Fix a couple more coding style nits. 1999-07-11 06:06:52 +00:00
Jason Evans
34582929f1 Modify previous changes to conform better to libc_r's coding style.
Always use mmap() for default-size stack allocation.  Use MAP_ANON instead
of MAP_STACK on the alpha architecture.

Reduce the amount of code executed while owning _gc_mutex during stack
allocation.
1999-07-11 05:56:37 +00:00
Jason Evans
876cc3dae0 Always use growable thread stacks on the i386. The VM_STACK kernel option
must be made default for the alpha before growable thread stacks are
enabled for the alpha.
1999-07-06 00:25:38 +00:00
Jason Evans
439cce0e4b Disable growable stacks by default, as advertised. 1999-07-05 00:38:12 +00:00
Jason Evans
ecaa6e8c9e Use growable stacks for thread stacks that are the default stack size.
Cache discarded default thread stacks for use in subsequent thread creations.

Create a red zone at the end of each stack (including the initial thread
stack), with the hope of causing a segfault if a stack overflows.

To activate these modifications, add -D_PTHREAD_GSTACK to CFLAGS in
src/lib/libc_r/Makefile.  Since the modifications depend on the VM_STACK
kernel option, I'm not sure how to safely use growable stacks by default.

Testing, as well as algorithmic and stylistic comments are welcome.
1999-07-05 00:35:19 +00:00
Dmitrij Tejblum
db06cf96d5 Defer signals, so we will not wait for SIGCHLD after it was delivered. 1999-06-29 19:57:07 +00:00
Dmitrij Tejblum
2467b7977b Fix few warnings on the alpha. 1999-06-23 15:01:22 +00:00
John Birrell
38329e8a07 Remove -DNOPOLL from the compilation flags now that there is a poll wrapper
in libc_r.

Bump the library version number (the scheduler now uses a poll syscall
instead of select).
1999-06-20 08:32:37 +00:00
John Birrell
02292f131a In the words of the author:
o The polling mechanism for I/O readiness was changed from
    select() to poll().  In additon, a wrapped version of poll()
    is now provided.

  o The wrapped select routine now converts each fd_set to a
    poll array so that the thread scheduler doesn't have to
    perform a bitwise search for selected fds each time file
    descriptors are polled for I/O readiness.

  o The thread scheduler was modified to use a new queue (_workq)
    for threads that need work.  Threads waiting for I/O readiness
    and spinblocks are added to the work queue in addition to the
    waiting queue.  This reduces the time spent forming/searching
    the array of file descriptors being polled.

  o The waiting queue (_waitingq) is now maintained in order of
    thread wakeup time.  This allows the thread scheduler to
    find the nearest wakeup time by looking at the first thread
    in the queue instead of searching the entire queue.

  o Removed file descriptor locking for select/poll routines.  An
    application should not rely on the threads library for providing
    this locking; if necessary, the application should use mutexes
    to protect selecting/polling of file descriptors.

  o Retrieve and use the kernel clock rate/resolution at startup
    instead of hardcoding the clock resolution to 10 msec (tested
    with kernel running at 1000 HZ).

  o All queues have been changed to use queue.h macros.  These
    include the queues of all threads, dead threads, and threads
    waiting for file descriptor locks.

  o Added reinitialization of the GC mutex and condition variable
    after a fork.  Also prevented reallocation of the ready queue
    after a fork.

  o Prevented the wrapped close routine from closing the thread
    kernel pipes.

  o Initialized file descriptor table for stdio entries at thread
    init.

  o Provided additional flags to indicate to what queues threads
    belong.

  o Moved TAILQ initialization for statically allocated mutex and
    condition variables to after the spinlock.

  o Added dispatching of signals to pthread_kill.  Removing the
    dispatching of signals from thread activation broke sigsuspend
    when pthread_kill was used to send a signal to a thread.

  o Temporarily set the state of a thread to PS_SUSPENDED when it
    is first created and placed in the list of threads so that it
    will not be accidentally scheduled before becoming a member
    of one of the scheduling queues.

  o Change the signal handler to queue signals to the thread kernel
    pipe if the scheduling queues are protected.  When scheduling
    queues are unprotected, signals are then dequeued and handled.

  o Ensured that all installed signal handlers block the scheduling
    signal and that the scheduling signal handler blocks all
    other signals.  This ensures that the signal handler is only
    interruptible for and by non-scheduling signals.  An atomic
    lock is used to decide which instance of the signal handler
    will handle pending signals.

  o Removed _lock_thread_list and _unlock_thread_list as they are
    no longer used to protect the thread list.

  o Added missing RCS IDs to modified files.

  o Added checks for appropriate queue membership and activity when
    adding, removing, and searching the scheduling queues.  These
    checks add very little overhead and are enabled when compiled
    with _PTHREADS_INVARIANTS defined.  Suggested and implemented
    by Tor Egge with some modification by me.

  o Close a race condition in uthread_close.  (Tor Egge)

  o Protect the scheduling queues while modifying them in
    pthread_cond_signal and _thread_fd_unlock.  (Tor Egge)

  o Ensure that when a thread gets a mutex, the mutex is on that
    threads list of owned mutexes.  (Tor Egge)

  o Set the kernel-in-scheduler flag in _thread_kern_sched_state
    and _thread_kern_sched_state_unlock to prevent a scheduling
    signal from calling the scheduler again.  (Tor Egge)

  o Don't use TAILQ_FOREACH macro while searching the waiting
    queue for threads in a sigwait state, because a change of
    state destroys the TAILQ link.  It is actually safe to do
    so, though, because once a sigwaiting thread is found, the
    loop ends and the function returns.  (Tor Egge)

  o When dispatching signals to threads, make the thread inherit
    the signal deferral flag of the currently running thread.
    (Tor Egge)

Submitted by: Daniel Eischen <eischen@vigrid.com> and
              Tor Egge <Tor.Egge@fast.no>
1999-06-20 08:28:48 +00:00
John Birrell
994d9b67a5 Added a missing comma to the static condition variable initialisation
definition.

Submitted by: David Leonard <David.Leonard@csee.uq.edu.au>, an OpenBSD guy.
1999-05-24 07:22:55 +00:00
John Birrell
eb9dc34d8b Fix a problem with static initialisation of mutexes and condition
variables.

Submitted by: Dan Eischen <eischen@vigrid.com>
1999-05-23 10:55:33 +00:00
John Birrell
65d33b21e6 Ensure that an existing thread gets it's state set to PS_DEAD to
prevent being rescheduled.

Submitted by: Dan Eischen <eischen@vigrid.com>
1999-05-16 05:25:37 +00:00
Nate Williams
283f072c78 - Fixed bug where we NULL'd before we freed the data causing a memory leak.
Submitted by:	 Ralf S. Engelschall
Obtained from:	PR i386/11713
1999-05-14 21:36:16 +00:00
John Birrell
33859c8093 Add mutex test program. 1999-05-09 07:50:31 +00:00
Jason Evans
c578efe575 Back out patch for cond_timedwait() bug from -current, since other changes
have made the patch obsolete, as pointed out by Daniel Eischen
<eischen@vigrid.com>.

PR:		bin/8872
1999-05-08 07:50:05 +00:00
Jason Evans
a1aefaec27 Apply patch included in bin/8872. This fixes a bug that occurs when
pthread_cond_timedwait() times out.

PR:		bin/8872
Submitted by:	Jason Evans <jasone@canonware.com>
Reviewed by:	David Schwartz <davids@webmaster.com>
1999-05-07 07:59:44 +00:00
John Birrell
58a7cc5d1b [ The author's description... ]
o Runnable threads are now maintained in priority queues.  The
    implementation requires two things:

      1.) The priority queues must be protected during insertion
          and removal of threads.  Since the kernel scheduler
          must modify the priority queues, a spinlock for
          protection cannot be used.   The functions
          _thread_kern_sched_defer() and _thread_kern_sched_undefer()
          were added to {un}defer kernel scheduler activation.

      2.) A thread (active) priority change can be performed only
          when the thread is removed from the priority queue.  The
          implementation uses a threads active priority when
          inserting it into the queue.

    A by-product is that thread switches are much faster.  A
    separate queue is used for waiting and/or blocked threads,
    and it is searched at most 2 times in the kernel scheduler
    when there are active threads.  It should be possible to
    reduce this to once by combining polling of threads waiting
    on I/O with the loop that looks for timed out threads and
    the minimum timeout value.

  o Functions to defer kernel scheduler activation were added.  These
    are _thread_kern_sched_defer() and _thread_kern_sched_undefer()
    and may be called recursively.  These routines do not block the
    scheduling signal, but latch its occurrence.  The signal handler
    will not call the kernel scheduler when the running thread has
    deferred scheduling, but it will be called when running thread
    undefers scheduling.

  o Added support for _POSIX_THREAD_PRIORITY_SCHEDULING.  All the
    POSIX routines required by this should now be implemented.
    One note, SCHED_OTHER, SCHED_FIFO, and SCHED_RR are required
    to be defined by including pthread.h.  These defines are currently
    in sched.h.  I modified pthread.h to include sched.h but don't
    know if this is the proper thing to do.

  o Added support for priority protection and inheritence mutexes.
    This allows definition of _POSIX_THREAD_PRIO_PROTECT and
    _POSIX_THREAD_PRIO_INHERIT.

  o Added additional error checks required by POSIX for mutexes and
    condition variables.

  o Provided a wrapper for sigpending which is marked as a hidden
    syscall.

  o Added a non-portable function as a debugging aid to allow an
    application to monitor thread context switches.  An application
    can install a routine that gets called everytime a thread
    (explicitly created by the application) gets context switched.
    The routine gets passed the pthread IDs of the threads that are
    being switched in and out.

Submitted by: Dan Eischen <eischen@vigrid.com>

Changes by me:

  o Added a PS_SPINBLOCK state to deal with the priority inversion
    problem most often (I think) seen by threads calling malloc/free/realloc.

  o Dispatch signals to the running thread directly rather than at a
    context switch to avoid the situation where the switch never occurs.
1999-03-23 05:07:56 +00:00
John Birrell
0883c4c31b Increase the size of private thread flags so that the test for a
thread trying to call pthread_exit() from a cleanup handler actually
works.

Submitted by: David Leonard <david.leonard@csee.uq.edu.au> OpenBSD
1999-01-15 00:21:03 +00:00
Warner Losh
d0c4729014 Fix a minor security problem in libc_r.
Submitted by: Alexandre Snarskii <snar@paranoia.ru>
Approved by: John Birrell
Reminded me that I'd been sitting on this too long: snar@paranoia.ru
1999-01-11 00:02:37 +00:00
John Birrell
7897c2a418 Don't hide mknod, it doesn't need a wrapper and never has had one. 1998-12-10 20:27:52 +00:00
Eivind Eklund
07bab7c6a4 Add support for pthread_mutexattr_settype(). As a side effect of
testing this, fix MUTEX_TYPE_COUNTING_FAST.  Recursive locks now work.
1998-11-28 23:52:58 +00:00
John Birrell
4896148e72 Interrupt threads waiting in select etc.
Submitted by: Alec Wolman <wolman@cs.washington.edu>
1998-11-15 10:01:34 +00:00
John Birrell
e7b7b3f3de Close a window between unlocking a spinlock and changing the thread state. 1998-11-15 09:58:26 +00:00
Dmitrij Tejblum
171a7528a8 Don't call pthread_mutex_lock with _SPINLOCK held.
Made pthread_cond_wait() more similar to pthread_cond_timedwait().

PR:		8375
1998-11-06 21:04:02 +00:00
Dmitrij Tejblum
4b12016bab Fix some bugs in pthread scheduler:
make pthread_yield() more reliable,
  threads always (I hope) preempted at least every 0.1 sec, as intended.

PR:		bin/7744
Submitted by:	"Richard Seaman, Jr." <dick@tar.com>
1998-10-09 19:01:30 +00:00
John Birrell
058716097d Revise test code for sigwait and add test code for sigsuspend.
Submitted by: Daniel M. Eischen <eischen@vigrid.com>
1998-09-30 07:08:09 +00:00
John Birrell
d3bb66886d Cosmetic cleansing. This code requires extra work to keep the garbage
collector thread running after a fork.
1998-09-30 06:41:16 +00:00
John Birrell
dc3a8b52c0 Move the cleanup code that frees memory allocated for a dead thread from
the thread kernel into a garbage collector thread which is started when
the fisrt thread is created (other than the initial thread). This
removes the window of opportunity where a context switch will cause a
thread that has locked the malloc spinlock, to enter the thread kernel,
find there is a dead thread and try to free memory, therefore trying
to lock the malloc spinlock against itself.

The garbage collector thread acts just like any other thread, so
instead of having a spinlock to control accesses to the dead thread
list, it uses a mutex and a condition variable so that it can happily
wait to be signalled when a thread exists.
1998-09-30 06:36:56 +00:00
John Birrell
05f3e91279 Use snprintf instead of sprintf to avoid long source file paths from
launching an application into space when someone tries to debug it.

The dead thread list now has it's own link pointer, so use that when
reporting the grateful dead.
1998-09-30 06:29:54 +00:00
John Birrell
54059e9f3f Implementation of an additional state called SIGWAIT (with the previous
one renamed to SIGSUSPEND) to fix sigwait().

Submitted by: Daniel M. Eischen <eischen@vigrid.com>
1998-09-30 06:27:31 +00:00
John Birrell
92ce833722 NULL a pointer after it is freed to avoid trying to free it again. 1998-09-30 06:24:57 +00:00
John Birrell
a247f83316 - Fix the debug macros.
-  Add support of a thread being listed in the dead thread list as well
   as the thread list.
-  Add a new thread state to make sigwait work properly. (Submitted by
   Daniel M. Eischen <eischen@vigrid.com>)
-  Add global variable for the garbage collector mutex and condition
   variable.
-  Delete a couple of prototypes that are no longer required.
-  Add a prototype for the garbage collector thread.
1998-09-30 06:22:07 +00:00
Dmitrij Tejblum
deb9688ae1 In libc_r, rename vfork syscall to _thread_sys_vfork and make vfork an alias
to fork. It is difficult to do real vfork in libc_r, since almost every
operation with file descriptsor changes _thread_fd_table and friends.

popen(3) works much better with this change.
1998-09-12 22:03:20 +00:00
Alexander Langer
cecc7b0974 Removed unused variables. 1998-09-07 21:55:01 +00:00
Alexander Langer
e66632a35c Removed some variable initializations which were unnecessary and divergent
from style(9).
1998-09-07 21:07:59 +00:00
Alexander Langer
23424a1f9a -Wall clean. 1998-09-07 19:23:55 +00:00
Alexander Langer
c0e366326f Implement pthread read/write locks as defined by Version 2 of the Single
UNIX Specification.

As with our standard mutexes, process shared locks are not supported at
this time.
1998-09-07 19:01:43 +00:00
John Birrell
5f867deba5 Don't automatically restart syscalls for the signals that the thread
kernel needs.
1998-08-26 20:55:31 +00:00
John Birrell
353a159590 Back out most of the last commit. It created problems with sigpause. 1998-08-26 20:50:42 +00:00
John Birrell
ad8f637466 Add support for building test programs. 1998-08-25 12:33:22 +00:00
John Birrell
42f37683ee Fix for sigwait problem.
Submitted by: Daniel M. Eischen <eischen@vigrid.com>
PR:           misc/7039
1998-08-25 11:19:14 +00:00
John Birrell
bbf157fac4 Add extra initialisation code that is required for processes that
are started instead of init (pid = 1). This allows an embedded
implementation quite like VxWorks, with (possibly) a single threaded
program running instead of init. The neat thing is that the same threaded
process can run in a multi-user workstation environment too.
1998-08-10 01:24:22 +00:00
Alexander Langer
b4ff1b7295 A style fix for my previous commit. 1998-08-02 23:07:25 +00:00
Alexander Langer
27aa2e8958 Fixed a race condition during the first lock/trylock of a statically
initialized mutex.  Statically initialized mutexes are actually
initialized at first use (pthread_mutex_lock/pthread_mutex_trylock).
To prevent concurrent initialization by multiple threads, all
static initializations are now serialized by a spinlock.

Reviewed by:	jb
1998-08-02 17:04:25 +00:00
Bruce Evans
bcc58f6898 Fixed a printf format error. Didn't fix assumption that sigset_t is
integral.
1998-06-30 18:00:11 +00:00
John Birrell
ff09ba5fbb Add the missing {} that caused the function to return ESRCH if it
had to wait for the thread to exit and if the caller didn't want the
thread exit status.
1998-06-25 00:04:21 +00:00
John Birrell
b9148b8a3e Don't allow a SIGCHLD to wake up a thread if the process has the default
signal handler installed for SIGCHLD. The ACE MT_SOCK_Test was hanging
as the result of being interrupted when it didn't expect to be.
1998-06-17 22:29:12 +00:00
John Birrell
d989fc8faa If a thread is waiting on a child process to complete, the SIGCHLD
signal can arrive before the thread is woken from it's wait4. In this
case, don't return an EINTR, just set the thread state to running and
the wait4 wrapper will loop and get the exit status of the process.
1998-06-17 03:53:16 +00:00
Peter Wemm
02a93d74e0 Don't compile in the use of poll() when building libc_r. This isn't
so much a "fix", rather a bandaid to buy time to fix it properly
within the thread engine.
1998-06-14 11:25:46 +00:00
John Birrell
597035b4db If a short write, only loop if no error. 1998-06-14 09:36:14 +00:00
John Birrell
0b99d9d8ac Add poll to the list of hidden syscalls so that it gets renamed. This
propagates a bug (that there is no poll wrapper in libc_r), but it
prevents GNU configure scripts from trying to use it in preference
to select. libc_r really needs to change it's wait interface to use
poll instead of select because poll is more a superset of select that
the other way around.

This should allow the Roxen web server to work out-of-the-box. It's
configuration intercae is kinda neat. The code isn't. Shiver. 8-)
1998-06-12 02:21:27 +00:00
John Birrell
06ca87e9f7 Update the caller's descriptor masks even if there are none ready for
I/O for those applications that don't believe the return value of zero as
meaning that THERE ARE *NO* DESCRIPTORS READY.
1998-06-12 02:17:18 +00:00
John Birrell
8eb25828ad Check the access mode in the flags before waiting on a read or a write
that might never be possible if the file was not opened in the corrent
mode. This prevents a hang for bad programs. Why do people code like that?
1998-06-10 22:28:45 +00:00
John Birrell
aef774b0d5 Remove SA_RESTART from the signal dispatch in user-space since this
seems to be tripping up a lot of applications.
1998-06-10 22:25:18 +00:00
John Birrell
3c165ef7b7 When doing a F_SETFL, read the flags back so that the ones stored
in the file descriptor table are exactly what the kernel knows subject
to the O_NONBLOCK flag being requested by the user.
1998-06-10 22:24:12 +00:00
John Birrell
627961e45f Add a commented out CFLAGS entry that can be uncommented to compile thread
lock debug into libc_r. I don't know if this is the best place to document
this, but at least it is recorded somewhere. 8-)
1998-06-09 23:25:13 +00:00
John Birrell
ddc8afd422 Implement compile time debug support instead of tracking file name and
line number every time a file descriptor is locked.

This looks like a big change but it isn't. It should reduce the size
of libc_r and make it run slightly faster.
1998-06-09 23:21:05 +00:00
John Birrell
3411c10600 Add support for compile time debug. This is enabled if libc_r is built
with -D_LOCK_DEBUG. This adds the file name and line number to each lock
call and these are stored in the spinlock structure. When using debug
mode, the lock function will check if the thread is trying to lock
something it has already locked. This is not supposed to happen because
the lock will be freed too early.

Without lock debug, libc_r should be smaller and slightly faster.
1998-06-09 23:13:10 +00:00
John Birrell
74ebed9424 POSIX says that pthread_exit() is not allowed to be called from a
cleanup destructor, so trap this case to prevent me from being being
burnt again by applications that try to do this. With this change, an
application (like one using a mis-configured ACE) will exit the process
after displaying a message quoting the POSIX section that the application
has violated.
1998-06-09 23:08:41 +00:00
John Birrell
27949f44dc Add compile time thread lock debug support.
Add a thread specific flag to trap the case where pthread_exit() is
called from a destructor in violation of the Posix standard.
1998-06-09 23:02:43 +00:00
John Birrell
2d8a580416 Add a warning message for a thread locking against itself. This is
not supposed to happen, but I have seen bogus g++ code that causes
it.
1998-06-06 07:27:06 +00:00
John Birrell
c6831395f4 Simplify the handling of thread specific data. Only track if a key
is allocated or not, rather than keeping a count and attempting to
know it it is in-use. POSIX says that once a key is deleted, using the
key again results in undefined behaviour.
1998-06-06 07:24:24 +00:00
John Birrell
c359f976b4 Re-design the thread specific key structure. 1998-06-06 07:20:23 +00:00
John Birrell
717d1611f4 I got the last commit back to front. 1998-06-06 07:02:27 +00:00
John Birrell
756534d117 Fix the signal behaviour for internal states which set the thread
state to running despite the SA_RESTART flag which is really just for
syscalls.
1998-06-05 23:31:55 +00:00
John Birrell
fca35cd32f I shouldn't do things early in the morning.
I shouldn't do things early in the morning.
[...]
I shouldn't do things early in the morning.
1998-06-01 02:14:34 +00:00
John Birrell
23c82db7a3 send and recv are wrappered in libc, so they shouldn't appear here. 1998-06-01 02:12:15 +00:00
John Birrell
8680cc3c47 Remove some syscalls that should have been renamed (libc_r doesn't need
to wrapper them) and add a couple that should have been there.
1998-05-31 23:53:50 +00:00
John Birrell
382306949d Add some missing syscall wrappers. 1998-05-31 23:48:30 +00:00
John Birrell
5d359b97bb Remove some stale code.
Pointed out by: Amancio
1998-05-31 23:47:06 +00:00
John Birrell
d972680a31 Don't restart a syscall when a SIGCHLD is received by a thread waiting
on a child process.
1998-05-31 23:46:01 +00:00
John Birrell
01029f8f17 Make a copy of the caller's iovec array, mallocing if necessary,
and modify that if the writev() syscall does not completely write
all bytes in a single call.
1998-05-27 00:44:58 +00:00
John Birrell
e5a8a007e1 When doing a blocking write, keep looping until all the bytes are
written without returning to the caller. This only occurs on pipes
where either the number of bytes written is greater than the pipe
buffer or if there is insufficient space in the pipe buffer because the
reader is reading slower than the writer is writing.
1998-05-25 21:45:52 +00:00
John Birrell
9839f9695a Treat the lock value as volatile. 1998-05-05 21:47:58 +00:00
John Birrell
b1ad8d9155 Cleanup in the child, not the parent.
Submitted by: Tor Egge <Tor.Egge@idi.ntnu.no>
1998-05-02 03:42:20 +00:00
John Birrell
96efcebdfc Fix the incremental priority increment.
PR: bin/6467 Marino Ladavac <lada@pc8811.gud.siemens.at>
1998-04-30 21:50:29 +00:00
John Birrell
7bb870ac66 Change the name of this source file so that libc_r builds it instead
of the one in libc that contains the weak symbol for __error. FreeBSD's
make accumulates paths to the point that it can find *anything*, possibly
including the car keys.
1998-04-30 09:04:10 +00:00
John Birrell
ccd1da1333 Add spinlock. 1998-04-29 11:03:34 +00:00
John Birrell
4a027d50c7 Change signal model to match POSIX (i.e. one set of signal handlers
for the process, not a separate set for each thread). By default, the
process now only has signal handlers installed for SIGVTALRM, SIGINFO
and SIGCHLD. The thread kernel signal handler is installed for other
signals on demand. This means that SIG_IGN and SIG_DFL processing is now
left to the kernel, not the thread kernel.

Change the signal dispatch to no longer use a signal thread, and
call the signal handler using the stack of the thread that has the
signal pending.

Change the atomic lock method to use test-and-set asm code with
a yield if blocked. This introduces separate locks for each type
of object instead of blocking signals to prevent a context
switch. It was this blocking of signals that caused the performance
degradation the people have noted.

This is a *big* change!
1998-04-29 09:59:34 +00:00
John Birrell
af139b98d4 Allow a thread dump to report the thread's sigmask when in the
PS_SIGWAIT state.
1998-04-17 09:39:37 +00:00
John Birrell
334fa8f215 When in PS_SIGWAIT state, still call signal handlers and set errno
to EINTR.
1998-04-17 09:37:41 +00:00
John Birrell
d60f0fa60d Change the FILE locking to be by FILE, not by the underlying fd as
it was. Add a FILE_WAIT state and queue threads waiting for a FILE
lock. Start using the sys/queue.h macros instead of the way that MIT
pthreads did it.

Add a thread name to the private thread structure and a non-POSIX
function to set this. This helps (me at least) when sending a SIGINFO
to a threaded process to get a /tmp/uthread.dump to see what the
<expletive deleted> threads are doing this time. It is nice to be
able to recognise (yes, I spell that with an 's' too) which threads
are which.
1998-04-11 07:47:22 +00:00
John Birrell
883674371e Enable static initialisation of mutexes and condition variables. 1998-04-04 11:33:01 +00:00
John Birrell
f9c7be5357 Rename static initializer defines for opaque structures so that the
POSIX specified names can be declared in pthread.h.
1998-04-04 10:58:12 +00:00
John Birrell
377aa2cbb6 Move the magic field initialisation to a place when it is more magic. 1998-04-04 07:27:29 +00:00
John Birrell
ed92686917 Add a magic field to the pthread structure to help recognize valid
threads from invalid ones. The pthread structure is opaque to the user
so this change does not cause any incompatibilities.

Hopefully this change will help code that was written for draft 4
fail gracefully if the programmer ignores the compiler warning about
the change in the level of indirection for the argument passed to
pthread_detach(). I got burnt, so I fixed then (expletive deleted)
thing.

These functions comply with the revised standard. That should shut
Terry up!
1998-04-03 09:31:15 +00:00
Peter Dufault
8a6472b723 Finish _POSIX_PRIORITY_SCHEDULING. Needs P1003_1B and
_KPOSIX_PRIORITY_SCHEDULING options to work.  Changes:

Change all "posix4" to "p1003_1b".  Misnamed files are left
as "posix4" until I'm told if I can simply delete them and add
new ones;

Add _POSIX_PRIORITY_SCHEDULING system calls for FreeBSD and Linux;

Add man pages for _POSIX_PRIORITY_SCHEDULING system calls;

Add options to LINT;

Minor fixes to P1003_1B code during testing.
1998-03-28 11:51:01 +00:00
John Birrell
0122d62264 Fix a problem of indirection unblocking signals that would have caused
signals to be unblocked even if they were already blocked when entering
the function.

Pointed out by: bde
1998-03-22 04:13:23 +00:00
John Birrell
9dbdb44326 When forking a process, only the running thread gets to live. All
other threads never see the light of day and if they leave things
locked, blame POSIX.
1998-03-09 06:54:50 +00:00
John Birrell
96ef575882 Add lib/libc/include as an directory to search for header files.
Change MACHINE references to MACHINE_ARCH.

Declare the names of the syscalls that need to be renamed to allow
for the functions that libc_r provides replacements for. This list
used to be in lib/libc/sys/Makefile.inc, but has been moved here
to keep that makefile tidy and remove the temptation for people to
add things to the list without adding a libc_r replacement function.
1998-03-09 05:09:43 +00:00