Commit Graph

223 Commits

Author SHA1 Message Date
jasone
2d7a958ca5 Fix logic errors in pthread_cond_wait() and pthread_cond_timedwait() that
could cause deadlock after interruption due to a signal.

Reviewed by:	deischen
2001-08-19 20:05:42 +00:00
jasone
6e7ccfd093 Fix a bug in canceling joining threads.
Do not detach canceled threads.

Reported by:		Arno Klaassen <arno@heho.snv.jussieu.fr>
Collaboration with:	deischen
2001-08-16 06:31:32 +00:00
imp
3e581274aa Make the name parameter const char *. 2001-08-11 05:16:00 +00:00
jasone
a9a7a5e9d6 Implement pthread_attr_[gs]etguardsize(). Non-default-size stacks used to
be malloc()ed, but they are now allocated using mmap(), just as the
default-size stacks are.  A separate cache of stacks is kept for
non-default-size stacks.

Collaboration with:	deischen
2001-07-20 04:23:11 +00:00
deischen
5cd1eeb556 Clear the in thread scheduler flag after jumping to the start of
a signal handler from the scheduler.

MFC after:	1 week
2001-06-29 17:09:07 +00:00
jasone
22f14eaadf Fix a race condition in pthread_join(). All of the following must occur
atomically:

1) Search _thread_list for the thread to join.
2) Search _dead_list for the thread to join.
3) Set the running thread as the joiner.

While we're at it, fix a race in the case where multiple threads try to
join on the same thread.  POSIX says that the behavior of multiple joiners
is undefined, but the fix is cheap as a result of the other fix.
2001-06-27 11:41:15 +00:00
jasone
adf603d4b1 Instead of using a join queue for each thread, use a single pointer to
keep track of a joiner.  POSIX only supports a single joiner, so this
simplification is acceptable.

At the same time, make sure to mark a joined thread as detached so that
its resources can be freed.

Reviewed by:	deischen
PR:		24345
2001-05-20 23:08:33 +00:00
jasone
3fbe60fc0d Condition variable waiters are queued in descending priority order, so
there is no need to wake all waiters to assure that the highest priority
thread is run.  As the semaphore code is written, there was no correctness
problem, but the change improves sem_post() performance.

Pointed out by:	deischen
2001-05-18 00:36:05 +00:00
jasone
047f94e139 Mark a thread that is suspended while sleeping as interrupted. 2001-05-16 21:58:45 +00:00
knu
fa8314227c Properly copy the P_ALTSTACK flag in struct proc::p_flag to the child
process on fork(2).

It is the supposed behavior stated in the manpage of sigaction(2), and
Solaris, NetBSD and FreeBSD 3-STABLE correctly do so.

The previous fix against libc_r/uthread/uthread_fork.c fixed the
problem only for the programs linked with libc_r, so back it out and
fix fork(2) itself to help those not linked with libc_r as well.

PR:		kern/26705
Submitted by:	KUROSAWA Takahiro <fwkg7679@mb.infoweb.ne.jp>
Tested by:	knu, GOTOU Yuuzou <gotoyuzo@notwork.org>,
		and some other people
Not objected by:	hackers
MFC in:		3 days
2001-05-07 18:07:29 +00:00
deischen
c6f06e4f28 Move the check for a pending signals to after the thread has been
placed in any scheduling queue(s).  The process of dispatching
signals to a thread can change its state which will attempt to add
or remove the thread from any scheduling queue to which it belongs.
This can break some assertions if the thread isn't in the queue(s)
implied by its state.

When adding dispatching a pending signal to a thread, be sure to
remove the signal from the threads set of pending signals.

PR:		27035
Tested by:	brian
MFC in:		1 week
2001-05-04 20:37:07 +00:00
markm
489b7590ab Compenate for header dethreading. 2001-05-01 09:32:34 +00:00
deischen
5e6e0f0b7b Typo; fix open() so that it is not a cancellation point when called
from libc.
2001-04-18 12:42:11 +00:00
deischen
9b1e997b4c Reinstall the alternate signal stack after a fork.
PR:		25110
Tested by:	knu
2001-04-18 12:40:30 +00:00
deischen
f0c50f0089 Clean up a bit. Use the correct TAILQ link when walking the thread
lists to free thread resources after a fork (in the child).  Also
remember to free the dead thread list.
2001-04-10 04:25:49 +00:00
deischen
ec98854211 Added a missing set of braces to a conditional that encompasses more than
one statement.
2001-04-10 04:22:24 +00:00
deischen
dd46d4e05f To be consistent, use the __weak_reference macro from <sys/cdefs.h>
instead of #pragma weak to create weak definitions.

Suggested by:	bde
2001-04-10 04:19:21 +00:00
tmm
aaa63ce9a5 Activate build of posix1e extensions in libc and libc_r that have been
moved in from libposix1e, and deactivate build of the soon-to-be-removed
libposix1e.

Approved by:	rwatson
Obtained from:	TrustedBSD Project
2001-04-04 18:17:28 +00:00
tmm
c8e81f3b49 Add thread safety wrappers for the posix1e syscalls that deal with file
descriptors.

Approved by:	rwatson
Obtained from:	TrustedBSD Project
2001-04-04 18:10:25 +00:00
iedowse
cc67d8ceca Add a leading underscore to the pthread_main_np function name, and
a "#pragma weak" directive linking the external symbol. This matches
the other pthread_* definitions, and ensures that users of this
function from within libc get the real version, not the stub.

Suggested by:	deischen
Reviewed by:	deischen, alfred
2001-04-03 22:25:39 +00:00
alfred
f67e4a8fc7 Bring in a hybrid of SunSoft's transport-independent RPC (TI-RPC) and
associated changes that had to happen to make this possible as well as
bugs fixed along the way.

  Bring in required TLI library routines to support this.

  Since we don't support TLI we've essentially copied what NetBSD
  has done, adding a thin layer to emulate direct the TLI calls
  into BSD socket calls.

  This is mostly from Sun's tirpc release that was made in 1994,
  however some fixes were backported from the 1999 release (supposedly
  only made available after this porting effort was underway).

  The submitter has agreed to continue on and bring us up to the
  1999 release.

  Several key features are introduced with this update:
    Client calls are thread safe. (1999 code has server side thread
    safe)
    Updated, a more modern interface.

  Many userland updates were done to bring the code up to par with
  the recent RPC API.

  There is an update to the pthreads library, a function
  pthread_main_np() was added to emulate a function of Sun's threads
  library.

  While we're at it, bring in NetBSD's lockd, it's been far too
  long of a wait.

  New rpcbind(8) replaces portmap(8) (supporting communication over
  an authenticated Unix-domain socket, and by default only allowing
  set and unset requests over that channel). It's much more secure
  than the old portmapper.

  Umount(8), mountd(8), mount_nfs(8), nfsd(8) have also been upgraded
  to support TI-RPC and to support IPV6.

  Umount(8) is also fixed to unmount pathnames longer than 80 chars,
  which are currently truncated by the Kernel statfs structure.

Submitted by: Martin Blapp <mb@imp.ch>
Manpage review: ru
Secure RPC implemented by: wpaul
2001-03-19 12:50:13 +00:00
deischen
0d4935c84e Correct a race condition where it was possible for a signaled
thread to become stranded and not placed in the run queue.

MFC Candidate

Reported by:	tegge
2001-03-09 16:05:43 +00:00
deischen
a7a408f67f Really set the flags for a private mutex (used by libc/libc_r). 2001-02-26 01:06:52 +00:00
deischen
ead1438fd8 Limit threads clock resolution to no less than 1000usec (1000Hz).
PR:		25300
Submitted by:	Tom Pavel <pavel@alum.mit.edu> (in part)
2001-02-26 01:05:33 +00:00
deischen
3de2e69a0d 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
deischen
aa95571c98 s/_thread_sys_write/__sys_write/
Submitted by:	Mike Heffner <mheffner@vt.edu>
2001-01-31 02:16:57 +00:00
deischen
e70d2f3aa9 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
deischen
c3dd7e380e _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
deischen
ee1de6a067 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
obrien
7de31c3e1c 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
phk
7e33fb5b20 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
deischen
a404d58b72 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
deischen
3ca85b60ef 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
deischen
400a63d937 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
deischen
7d8a005612 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
deischen
282d572dc0 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
deischen
b593b76bee Delete 4 lines of misleading/incorrect comments. 2000-11-16 19:15:56 +00:00
deischen
5ed7dea44c 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
deischen
a7772ecabd 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
deischen
69c0393f8e 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
deischen
070083863e 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
jdp
c7a7ecd8c5 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
deischen
727a941a16 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
deischen
fba698949b 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
7a60214eea Try and get libc_r to compile again on the alpha after deischen's commit 2000-10-17 06:31:40 +00:00
brian
97cc68f9c3 #include <sys/types.h> 2000-10-15 20:04:09 +00:00
deischen
4e7266f987 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
sobomax
7db199851c Add thread-safe wrapper for fpathconf(2) syscall.
Reviewed by:	jlemon
2000-09-19 18:01:03 +00:00
jasone
8f49d9a949 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
c90f528c48 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