Commit Graph

18 Commits

Author SHA1 Message Date
David Xu
f4213b9006 To support stack unwinding for cancellation points, add -fexceptions flag
for them, two functions _pthread_cancel_enter and _pthread_cancel_leave
are added to let thread enter and leave a cancellation point, it also
makes it possible that other functions can be cancellation points in
libraries without having to be rewritten in libthr.
2010-09-25 01:57:47 +00:00
David Xu
9b0f1823b5 Use umtx to implement process sharable semaphore, to make this work,
now type sema_t is a structure which can be put in a shared memory area,
and multiple processes can operate it concurrently.
User can either use mmap(MAP_SHARED) + sem_init(pshared=1) or use sem_open()
to initialize a shared semaphore.
Named semaphore uses file system and is located in /tmp directory, and its
file name is prefixed with 'SEMD', so now it is chroot or jail friendly.
In simplist cases, both for named and un-named semaphore, userland code
does not have to enter kernel to reduce/increase semaphore's count.
The semaphore is designed to be crash-safe, it means even if an application
is crashed in the middle of operating semaphore, the semaphore state is
still safely recovered by later use, there is no waiter counter maintained
by userland code.
The main semaphore code is in libc and libthr only has some necessary stubs,
this makes it possible that a non-threaded application can use semaphore
without linking to thread library.
Old semaphore implementation is kept libc to maintain binary compatibility.
The kernel ksem API is no longer used in the new implemenation.

Discussed on: threads@
2010-01-05 02:37:59 +00:00
John Baldwin
4e1fc19cea Revert the previous change to pthread_once() stub in libc. It is actually
a feature that libstdc++ depends on to simulate the behavior of libc's
internal '__isthreaded' variable.  One benefit of this is that _libc_once()
is now private to _once_stub.c.

Requested by:	kan
2009-11-20 20:43:34 +00:00
John Baldwin
5bcfe82e47 Add an internal _once() method. This works identical to pthread_once(3)
with the additional property that it is safe for routines in libc to use
in both single-threaded and multi-threaded processes.  Multi-threaded
processes use the pthread_once() implementation from the threading library
while single-threaded processes use a simplified "stub" version internal
to libc.  The libc stub-version of pthread_once() now also uses the
simplified "stub" version as well instead of being a nop.

Reviewed by:	deischen, Matthew Fleming @ Isilon
Suggested by:	alc
MFC after:	1 week
2009-11-20 19:19:51 +00:00
Joe Marcus Clarke
ad1e5416ab Correct the pthread stub prototype for pthread_mutexattr_settype to allow for
the type argument.  This is known to fix some pthread_mutexattr_settype()
invocations, especially when it comes to pulseaudio.

Approved by:	kib
		deischen (threads)
MFC after:	3 days
2009-10-01 18:23:50 +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
Daniel Eischen
f4fb3299fa Fix a stub function so that is has the correct number of
arguments.  While I'm here, correct a couple of [tab] alignments.

Submitted by:	bland
2005-11-12 16:00:29 +00:00
Alexander Kabaev
132cc0756e Use newly added __used attribute to keep static function symbols from being
eliminated by compiler optimizer.
2004-07-29 18:07:08 +00:00
Daniel Eischen
fcfc20c88a Argh, change declaration of two-dimensional array so that it actually
builds.
2002-11-13 21:55:22 +00:00
Daniel Eischen
fb22a377c6 Use a jump table (a la Solaris) for pthread routines with default
entries in the table being stubs.  While I'm here, add macros to
auto-generate the stubs.  A conforming threads library can override
the stub routines by filling in the jump table.

Add some entries to namespace.h and sync un-namespace.h to it.
Also add a comment to remind folks to update un-namespace.h
when changing namespace.h.
2002-11-13 18:12:09 +00:00
Doug Rabson
ceb336710e * Add stubs for pthread_cond_broadcast.
* Fix typos in rwlock stubs.
* Add pthread_XXX counterparts to the _pthread_XXX stubs which libraries
  like libX11 can use to ensure thread-safety without requiring the use
  of a thread library.

Submitted by: Terry Lambert (pthread_cond_broadcast)
Reviewed by: deischen
2002-11-01 09:37:17 +00:00
Alfred Perlstein
4f68734dc6 add a stub for pthread_cond_destroy. 2002-09-19 01:09:49 +00:00
David E. O'Brien
ea8d448a92 Fix SCM ID's. 2002-02-01 00:57:29 +00:00
Ian Dowse
f9f6897972 Make the non-threaded stub for pthread_sigmask() a no-op instead
of calling sigprocmask(). This matches the behaviour of thr_sigsetmask()
on Solaris; _pthread_sigmask_stub was added purely for compatibility
with Solaris (for TI-RPC), so it might as well do the same thing.

This fixes the problem where client RPC calls ignored all signals
for the complete duration of the RPC. This behaviour is currently
necessary in the threaded case due to locking issues, but was never
intended to occur in non-threaded programs.

Reviewed by:	deischen
2001-06-11 23:18:22 +00:00
Daniel Eischen
54fd7f685f To be consistent, use the __weak_reference macro from <sys/cdefs.h>
instead of #pragma weak to create weak definitions.  This macro is
improperly named, though, since a weak definition is not the same
thing as a weak reference.

Suggested by:	bde
2001-04-10 04:11:50 +00:00
Alfred Perlstein
8360efbd6c 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
Daniel Eischen
29ac6bd228 libc MT-safety, part 2.
Add a lock to FILE.  flockfile and friends are now implemented
(for the most part) in libc.  flockfile_debug is implemented in
libc_r; I suppose it's about time to kill it but will do it in
a future commit.

Fix a potential deadlock in _fwalk in a threaded environment.
A file flag (__SIGN) was added to stdio.h that, when set, tells
_fwalk to ignore it in its walk.  This seemed to be needed in
refill.c because each file needs to be locked when flushing.

Add a stub for pthread_self in libc.  This is needed by flockfile
which is allowed by POSIX to be recursive.

Make fgetpos() error return value (-1) match man page.

Remove recursive calls to locked functions (stdio); I think I've
got them all, but I may have missed a couple.

A few K&R -> ANSI conversions along with removal of a few instances
of "register".

$Id$ -> $FreeBSD$ in libc/stdio/rget.c

Not objected to:	-arch, a few months ago
2001-02-11 22:06:43 +00:00
Daniel Eischen
d201fe46e3 Remove _THREAD_SAFE and make libc thread-safe by default by
adding (weak definitions to) stubs for some of the pthread
functions.  If the threads library is linked in, the real
pthread functions will pulled in.

Use the following convention for system calls wrapped by the
threads library:
	__sys_foo - actual system call
	_foo - weak definition to __sys_foo
	foo - weak definition to __sys_foo

Change all libc uses of system calls wrapped by the threads
library from foo to _foo.  In order to define the prototypes
for _foo(), we introduce namespace.h and un-namespace.h
(suggested by bde).  All files that need to reference these
system calls, should include namespace.h before any standard
includes, then include un-namespace.h after the standard
includes and before any local includes.  <db.h> is an exception
and shouldn't be included in between namespace.h and
un-namespace.h  namespace.h will define foo to _foo, and
un-namespace.h will undefine foo.

Try to eliminate some of the recursive calls to MT-safe
functions in libc/stdio in preparation for adding a mutex
to FILE.  We have recursive mutexes, but would like to avoid
using them if possible.

Remove uneeded includes of <errno.h> from a few files.

Add $FreeBSD$ to a few files in order to pass commitprep.

Approved by:	-arch
2001-01-24 13:01:12 +00:00