Commit Graph

199 Commits

Author SHA1 Message Date
Daniel Eischen
f434cd45ed Remove (int) file descriptor locking. It should be up to the
application to provide locking for I/O operations.  This doesn't
break any of my tests, but the old behavior can be restored by
compiling with _FDLOCKS_ENABLED.  This will eventually be removed
when it is obvious it does not cause any problems.

Remove most of flockfile implementation, with the exception of
flockfile_debug.

Make error messages more informational (submitted by Mike Heffner
<spock@techfour.net>, who's now known as mikeh@FreeBSD.org).
2001-02-11 22:07:32 +00:00
Daniel Eischen
f8a19b12fb s/_thread_sys_write/__sys_write/
Submitted by:	Mike Heffner <mheffner@vt.edu>
2001-01-31 02:16:57 +00:00
Daniel Eischen
f47892a9f7 Unbreak world by correctly specifying the prototype for __sys_aio_suspend.
A make buildworld was done but not with the committed pthread_private.h.

Reported by:	Manfred Antar <null@pozo.com>
2001-01-29 18:59:53 +00:00
Daniel Eischen
221b1e69c5 _exit in libc is now __sys_exit not __sys__exit.
Add another check for thread library initialization (jdp, we
really need a way to get _thread_init called at program start
before any constructors are run).
2001-01-29 03:24:23 +00:00
Daniel Eischen
e5106342c6 Add weak definitions for wrapped system calls. In general:
_foo - wrapped system call
	foo - weak definition to _foo

and for cancellation points:

	_foo - wrapped system call
	__foo - enter cancellation point, call _foo(), leave
	        cancellation point
	foo - weak definition to __foo

Change use of global _thread_run to call a function to get the
currently running thread.

Make all pthread_foo functions weak definitions to _pthread_foo,
where _pthread_foo is the implementation.  This allows an application
to provide its own pthread functions.

Provide slightly different versions of pthread_mutex_lock and
pthread_mutex_init so that we can tell the difference between
a libc mutex and an application mutex.  Threads holding mutexes
internal to libc should never be allowed to exit, call signal
handlers, or cancel.

Approved by:	-arch
2001-01-24 13:03:38 +00:00
David E. O'Brien
cad1dd7bb4 Force strong references to several pthread_* functions which are weakly
referenced to by libgcc.a.

This is needed when linking statically as SVR4 (ie, ELF) behavior is to only
link in a module if it satisfies an undefined strong reference from somewhere.
(this surprises a lot of people) Things are different when using shared libs,
the entire library and its modules and their symbols are available at run-time
(when the weak reference is seen to still be unsatisfied and is satisfied on
the spot), this is not the case with static libs.

Thus one can have a static binary with unresolved week references, and at
run-time dereference a NULL pointer.

Submitted by:	eischen
2001-01-06 06:07:52 +00:00
Poul-Henning Kamp
f42abb1fef Use macro API to <sys/queue.h>
Submitted by:	"Peter Avalos" <pavalos@theshell.com>
Reviewed by:	/sbin/md5 [*]

[*] This line appears courtesy of Mr. Warner Losch, all rights reversed.
2000-12-31 10:28:01 +00:00
Daniel Eischen
9ffc4537c8 When retrieving the time of day in nanosleep(), store it in the
global time of day.  This costs us nothing, but is a bit of a hack
to work around a process blocking and not having the time updated
by an ITIMER_PROF signal.

PR:		23679
2000-12-20 17:04:12 +00:00
Daniel Eischen
d73eb8c8ca Enable check for pending signals after calling a signal handler.
Restoration of a threads signal mask after invocation of a signal
handler may allow pending signals to become deliverable.

PR:		23647
2000-12-20 16:55:57 +00:00
Daniel Eischen
47c1571785 Change a "while {}" loop to a "do {} while" to allow it to be
executed at least once, fixing pthread_mutex_lock() for recursive
mutex lock attempts.

Correctly set a threads signal mask while it is executing a signal
handler.  The mask should be the union of its current mask, the
signal being handled, and the mask from the signal action.

Reported by: Dan Nelson <dnelson@emsphone.com>

MFC Candidate
2000-11-20 13:12:44 +00:00
Daniel Eischen
499c499c61 Fix MD macros to work for alpha. Without this fix, threads under alpha
seem to be totally broke.

MFC Candidate

Submitted by:	gallatin
2000-11-20 01:57:19 +00:00
Daniel Eischen
f17033e38d Fix a bug where a statically initialized condition variable
was not getting properly initialized in pthread_cond_signal()
and pthread_cond_broadcast().  Reportedly, this can cause
an application to die.

MFC candidate

Submitted by:	ade
2000-11-16 22:50:33 +00:00
Daniel Eischen
810888e2f8 Delete 4 lines of misleading/incorrect comments. 2000-11-16 19:15:56 +00:00
Daniel Eischen
eb4463fde6 When entering the scheduler from the signal handler, tell
the kernel to (re)use the alternate signal stack.  In this
case, we don't return normally from the signal handler,
so the kernel still thinks we are using the signal stack.
The fixes a nasty bug where the signal handler can start
fiddling with the stack of a thread while the handler is
actually running on the same stack.

MFC candidate
2000-11-14 20:00:19 +00:00
Daniel Eischen
00e550955e Correct the logic for checking the emptiness of the waiting queue.
This fixes a potential problem where the file descriptors would not
be polled causing waiting threads to stay waiting.  Doh!

MFC candidate.
2000-11-11 22:20:36 +00:00
Daniel Eischen
b5a8a15c2f Don't needlessly poll file descriptors when there are no
file descriptors needing to be polled (Doh!).  Reported
by Dan Nelson <dnelson@emsphone.com>.

Don't install and start the scheduling timer until the
first thread is created.  This prevents the overhead of
having a periodic scheduling signal in a single threaded
program.  Reported by Dan Nelson <dnelson@emsphone.com>.

Allow builtin longjmps out of application installed
signal handlers without the need perform any post-handler
cleanup:

  o Change signal handling to save the threads interrupted
    context on the stack.  The threads current context is
    now always stored in the same place (in the pthread).
    If and when a signal handler returns, the interrupted
    context is copied back to the storage area in the pthread.

  o Before calling invoking a signal handler for a thread,
    back the thread out of any internal waiting queues
    (mutex, CV, join, etc) to which it belongs.

Rework uthread_info.c a bit to make it easier to change
the format of a thread dump.

Use an alternal signal stack for the thread library's
signal handler.  This allows us to fiddle with the main
threads stack without fear of it being in use.

Reviewed by:	jasone
2000-11-09 05:08:26 +00:00
Daniel Eischen
9a6b83bf3b Prevent the thread-safe version of kevent from getting
into an infinite loop when a timeout value is supplied
and the timeout expires.

Reported by:	Dan Nelson <dnelson@emsphone.com>
Reviewed by:	jasone, jlemon
2000-11-09 05:00:06 +00:00
John Polstra
a9bda22cd6 At the beginning of pthread_mutex_lock(), call _thread_init() if
necessary.  This works around a bug in old versions of libgcc_r.a
which are statically linked into old executables.
2000-11-01 20:19:07 +00:00
Daniel Eischen
c418675341 Make pthread_kill() know about temporary signal handlers installed
by sigwait().  This prevents a signal from being sent to the process
when there are no application installed signal handlers.

Correct a typo in sigwait (foo -> foo[i]).
2000-10-25 11:46:07 +00:00
Daniel Eischen
2fbba8b1b8 We use ___setjmp (non-signal saving) to setup a signal frame. When
adding a signal frame to a thread, be sure to label the context
correctly so we don't restore an uninitialized process mask.

Reported by:	kimc@W8HD.ORG and Andrey Rouskol <anry@sovintel.ru>
2000-10-22 18:35:11 +00:00
Peter Wemm
100063a74b Try and get libc_r to compile again on the alpha after deischen's commit 2000-10-17 06:31:40 +00:00
Brian Somers
9c8ec4f794 #include <sys/types.h> 2000-10-15 20:04:09 +00:00
Daniel Eischen
fbeb36e4bf Implement zero system call thread switching. Performance of
thread switches should be on par with that under scheduler
activations.

  o Timing is achieved through the use of a fixed interval
    timer (ITIMER_PROF) to count scheduling ticks instead
    of retrieving the time-of-day upon every thread switch
    and calculating elapsed real time.

  o Polling for I/O readiness is performed once for each
    scheduling tick instead of every thread switch.

  o The non-signal saving/restoring versions of setjmp/longjmp
    are used to save and restore thread contexts.  This may
    allow the removal of _THREAD_SAFE macros from setjmp()
    and longjmp() - needs more investigation.

Change signal handling so that signals are handled in the
context of the thread that is receiving the signal.  When
signals are dispatched to a thread, a special signal handling
frame is created on top of the target threads stack.  The
frame contains the threads saved state information and a new
context in which the thread can run.  The applications signal
handler is invoked through a wrapper routine that knows how
to restore the threads saved state and unwind to previous
frames.

Fix interruption of threads due to signals.  Some states
were being improperly interrupted while other states were
not being interrupted.  This should fix several PRs.

Signal handlers, which are invoked as a result of a process
signal (not by pthread_kill()), are now called with the
code (or siginfo_t if SA_SIGINFO was set in sa_flags) and
sigcontext_t as received from the process signal handler.

Modify the search for a thread to which a signal is delivered.
The search algorithm is now:

  o First thread found in sigwait() with signal in wait mask.
  o First thread found sigsuspend()'d on the signal.
  o Current thread if signal is unmasked.
  o First thread found with signal unmasked.

Collapse machine dependent support into macros defined in
pthread_private.h.  These should probably eventually be moved
into separate MD files.

Change the range of settable priorities to be compliant with
POSIX (0-31).  The threads library uses higher priorities
internally for real-time threads (not yet implemented) and
threads executing signal handlers.  Real-time threads and
threads running signal handlers add 64 and 32, respectively,
to a threads base priority.

Some other small changes and cleanups.

PR:		17757 18559 21943
Reviewed by:	jasone
2000-10-13 22:12:32 +00:00
Maxim Sobolev
24a1dab36f Add thread-safe wrapper for fpathconf(2) syscall.
Reviewed by:	jlemon
2000-09-19 18:01:03 +00:00
Jason Evans
f3ee83c3bf The second call to _thread_kern_sig_defer() in sem_post() should be a call
to _thread_kern_sig_undefer().
2000-08-23 07:59:50 +00:00
Alfred Perlstein
022daa34f2 Fix an off-by-one error in the recursive mutex handling that made it
prematurely release recursive mutexes.

Test case provided by: Bradley T. Hughes <bhughes@trolltech.com>
Reviewed by: deischen
2000-08-13 01:30:36 +00:00
Jason Evans
f8842c0a18 kevent() is not a POSIX cancellation point, so _kevent() need not be
defined.

Remove some unnecessary header file inclusions.
2000-08-08 00:12:35 +00:00
Jonathan Lemon
532c92a865 Add wrapper for kevent() syscall
Noted as missing by: nicolas.leonard@animaths.com
2000-08-07 16:51:56 +00:00
Jason Evans
b167c9a5c1 Make sem_post() safe to call from within a signal handler, as required by
POSIX/SUSv2.
2000-08-01 21:19:09 +00:00
Doug Rabson
678ef1b49e Call _thread_init() from pthread_once() if it has not already been called.
This fixes a segfault in some C++ programs which use exceptions before
main() has been called (i.e. from global constructors).

Reviewed by: deischen
2000-07-21 09:31:13 +00:00
Jason Evans
8e234adf86 Change my email address in the copyright notices for the sake of consistency
(jasone@canonware.com --> jasone@freebsd.org).
2000-07-18 01:38:19 +00:00
Jason Evans
390a1cd5eb Deal correctly with statically initialized condition variables in
pthread_cond_signal(), pthread_cond_broadcast(), and pthread_cond_timedwait().

Do not dump core in pthread_cond_timedwait() (due to a NULL pointer
dereference) if attempting to wait on an uninitialized condition variable.

PR:	bin/18099
2000-07-17 22:55:05 +00:00
Jason Evans
8d107d1210 If multiple threads are blocked in sigwait() for the same signal that does
not have a user-supplied signal handler, when a signal is delivered, one
thread will receive the signal, and then the code reverts to having no
signal handler for the signal.  This can leave the other sigwait()ing
threads stranded permanently if the signal is later ignored, or can result
in process termination when the process should have delivered the signal to
one of the threads in sigwait().

To fix this problem, maintain a count of sigwait()ers for each signal that
has no default signal handler.  Use the count to correctly install/uninstall
dummy signal handlers.

Reviewed by:	deischen
2000-06-27 21:30:16 +00:00
Jason Evans
314be1347b pthread_mutex_lock(), pthread_cond_trywait(), and pthread_cond_wait() are
not allowed to return EINTR, but use of pthread_suspend_np() could cause
EINTR to be returned.  To fix this, restructure pthread_suspend_np() so that
it does not interrupt a thread that is waiting on a mutex or condition, and
keep enough state around that pthread_resume_np() can fix things up
afterwards.

Reviewed by:	deischen
2000-06-14 17:17:41 +00:00
Jake Burkholder
e39756439c Back out the previous change to the queue(3) interface.
It was not discussed and should probably not happen.

Requested by:		msmith and others
2000-05-26 02:09:24 +00:00
Jake Burkholder
740a1973a6 Change the way that the queue(3) structures are declared; don't assume that
the type argument to *_HEAD and *_ENTRY is a struct.

Suggested by:	phk
Reviewed by:	phk
Approved by:	mdodd
2000-05-23 20:41:01 +00:00
Jason Evans
ccb3a748f4 Fix a memory leak. pthread_set_name_np() allocates space for a name, but
was not deallocating space for the previous name, if any.

PR:	misc/18504
2000-05-16 22:08:14 +00:00
Jason Evans
40316fa981 Fix a memory leak. pthread_set_name_np() allocates space for a name, but
_thread_gc() was not deallocating it.

PR:	misc/18504
2000-05-16 21:57:12 +00:00
Bruce Evans
80a07932e7 Fixed missing consts for function parameters, so that the code matches
the man page and POSIX.1.  Fixed nearby misformatting.  Fixed a missing
prototype.
2000-05-11 15:57:17 +00:00
Jason Evans
4c089f4dff Add missing man pages. Fix various compliance bugs, mostly having to do with
error return values.  Implement pthread_mutexattr_gettype().

PR:		docs/16537, docs/17538
2000-05-02 06:51:40 +00:00
Jason Evans
98a1f447bb Add a wrapper for the sendfile() system call.
PR:		bin/17366
2000-04-27 00:59:44 +00:00
Jason Evans
7e5e179982 Explicitly include sys/cdefs.h to get the definition of __strong_reference(),
rather than getting lucky due to header dependencies.
2000-03-18 22:36:46 +00:00
Daniel Eischen
1d013a86ed Fix pthread_suspend_np/pthread_resume_np. For the record, suspending a
thread waiting on an event (I/O, condvar, etc) will, when resumed using
pthread_resume_np, return with EINTR.  For example, suspending and resuming
a thread blocked on read() will not requeue the thread for the read, but
will return -1 with errno = EINTR.  If the suspended thread is in a critical
region, the thread is suspended as soon as it leaves the critical region.

Fix a bogon in pthread_kill() where a signal was being delivered twice
to threads waiting in sigwait().

Reported by (suspend/resume bug):	jdp
Reviewed by:	jasone
2000-03-15 13:59:27 +00:00
Jason Evans
8a668b9049 For errors, return -1 and set errno to indicate the error type, rather than
returning the error directly.

For sem_post(), make sure that the correct thread is woken up.  This has
unfortunate performance implications, but is necessary for POSIX compliance.

Approved by:	jkh
2000-02-16 19:34:53 +00:00
Jason Evans
d77639f25f Use __strong_reference() instead of __weak_reference() to assure that the
weak symbols of the same name are not used.
2000-01-29 22:53:55 +00:00
Jason Evans
4ec6f67d10 Use _fcntl() (not fcntl()) inside of fcntl().
Reported by:	green
2000-01-28 22:10:27 +00:00
Jason Evans
9233c4d942 Simplify sytem call renaming. Instead of _foo() <-- _libc_foo <-- foo(),
just use _foo() <-- foo().  In the case of a libpthread that doesn't do
call conversion (such as linuxthreads and our upcoming libpthread), this
is adequate.  In the case of libc_r, we still need three names, which are
now _thread_sys_foo() <-- _foo() <-- foo().

Convert all internal libc usage of: aio_suspend(), close(), fsync(), msync(),
nanosleep(), open(), fcntl(), read(), and write() to _foo() instead of foo().

Remove all internal libc usage of: creat(), pause(), sleep(), system(),
tcdrain(), wait(), and waitpid().

Make thread cancellation fully POSIX-compliant.

Suggested by:	deischen
2000-01-27 23:07:25 +00:00
Jason Evans
0c5d1a3361 Fix millisecond to nanosecond conversion.
PR:		misc/16245
2000-01-22 09:15:15 +00:00
Jason Evans
beab1ec9b5 Minor *jmp() cleanups. 2000-01-20 21:53:59 +00:00
Jason Evans
120bfc9ded Add sem_*() functions. Named semaphores and process-shared semaphores
are not supported by this implementation, and the error return values
from sem_init(), sem_open(), sem_close(), and sem_unlink() reflect this.

Approved by:	jkh
2000-01-20 07:54:49 +00:00