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* Remove the libkse directory. It was unhooked from the build and kernelbrooks2014-04-161-210/+0
| | | | | | | support removed in 2008 (prior to 8.0). Approved by: deischen, imp MFC after: 3 days
* Remove hacks to allow libkse to export its symbols in the LIBTHREAD_1_0deischen2007-12-161-10/+0
| | | | | version namespace which was needed before the library version was bumped.
* WARNS=3'ify.deischen2007-11-301-3/+14
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* Remove 3rd clause, renumber, ok per emailimp2007-01-121-4/+1
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* Add compatibility symbol maps. libpthread (.so.1 and .so.2)deischen2006-03-131-0/+10
| | | | | | | | | | | used LIBTHREAD_1_0 as its version definition, but now needs to define its symbols in the same namespace used by libc. The compatibility hooks allows you to use libraries and binaries built and linked to libpthread before libc was built with symbol versioning. The shims can be removed if libpthread is given a version bump. Reviewed by: davidxu
* Fix a POSIX conformance bug. POSIX says sigwait should return error numberdavidxu2004-03-171-3/+3
| | | | in return value not in errno.
* Rename _thr_enter_cancellation_point to _thr_cancel_enter, renamedavidxu2003-12-091-6/+6
| | | | | | | | | | | | | | | | | | | | | _thr_leave_cancellation_point to _thr_cancel_leave, add a parameter to _thr_cancel_leave to indicate whether cancellation point should be checked, this gives us an option to not check cancallation point if a syscall successfully returns to avoid any leaks, current I have creat(), open() and fcntl(F_DUPFD) to not check cancellation point after they sucessfully returned. Replace some members in structure kse with bit flags to same some memory. Conditionally compile THR_ASSERT to nothing if _PTHREAD_INVARIANTS is not defined. Inline some small functions in thr_cancel.c. Use __predict_false in thr_kern.c for some executed only once code. Reviewd by: deischen
* Treat initial thread as scope system thread when KSE mode is not activateddavidxu2003-08-181-2/+1
| | | | | | | | | yet, so we can protect some locking code from being interrupted by signal handling. When KSE mode is turned on, reset the thread flag to scope process except we are running in 1:1 mode which we needn't turn it off. Also remove some unused member variables in structure kse. Tested by: deischen
* Simplify sigwait code a bit by using a waitset and removing oldsigmask.davidxu2003-07-271-5/+5
| | | | Reviewed by: deischen
* o Eliminate upcall for PTHREAD_SYSTEM_SCOPE thread, now itdavidxu2003-07-171-101/+50
| | | | | | | | | | | | | is system bound thread and when it is blocked, no upcall is generated. o Add ability to libkse to allow it run in pure 1:1 threading mode, defining SYSTEM_SCOPE_ONLY in Makefile can turn on this option. o Eliminate code for installing dummy signal handler for sigwait call. o Add hash table to find thread. Reviewed by: deischen
* POSIX says if a thread is in sigwait state, although a signal may not indavidxu2003-07-091-5/+6
| | | | | | | | its waitset, but if the signal is not masked by the thread, the signal can interrupt the thread and signal action can be invoked by the thread, sigwait should return with errno set to EINTR. Also save and restore thread internal state(timeout and interrupted) around signal handler invoking.
* Correctly lock/unlock signal lock. I must be in bad state, need to sleep.davidxu2003-07-041-1/+2
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* Always check and restore sigaction previously set, also access user parameterdavidxu2003-07-041-4/+7
| | | | outside of lock.
* Because there are only _SIG_MAXSIG elements in thread siginfo array,davidxu2003-06-301-1/+1
| | | | use [signal number - 1] as subscript to access the array.
* o Use a daemon thread to monitor signal events in kernel, if pendingdavidxu2003-06-281-68/+142
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | signals were changed in kernel, it will retrieve the pending set and try to find a thread to dispatch the signal. The dispatching process can be rolled back if the signal is no longer in kernel. o Create two functions _thr_signal_init() and _thr_signal_deinit(), all signal action settings are retrieved from kernel when threading mode is turned on, after a fork(), child process will reset them to user settings by calling _thr_signal_deinit(). when threading mode is not turned on, all signal operations are direct past to kernel. o When a thread generated a synchoronous signals and its context returned from completed list, UTS will retrieve the signal from its mailbox and try to deliver the signal to thread. o Context signal mask is now only used when delivering signals, thread's current signal mask is always the one in pthread structure. o Remove have_signals field in pthread structure, replace it with psf_valid in pthread_signal_frame. when psf_valid is true, in context switch time, thread will backout itself from some mutex/condition internal queues, then begin to process signals. when a thread is not at blocked state and running, check_pending indicates there are signals for the thread, after preempted and then resumed time, UTS will try to deliver signals to the thread. o At signal delivering time, not only pending signals in thread will be scanned, process's pending signals will be scanned too. o Change sigwait code a bit, remove field sigwait in pthread_wait_data, replace it with oldsigmask in pthread structure, when a thread calls sigwait(), its current signal mask is backuped to oldsigmask, and waitset is copied to its signal mask and when the thread gets a signal in the waitset range, its current signal mask is restored from oldsigmask, these are done in atomic fashion. o Two additional POSIX APIs are implemented, sigwaitinfo() and sigtimedwait(). o Signal code locking is better than previous, there is fewer race conditions. o Temporary disable most of code in _kse_single_thread as it is not safe after fork().
* Add a method of yielding the current thread with the schedulerdeischen2003-05-161-2/+1
| | | | | | | | | | | | | | | | | | | | | | | lock held (_thr_sched_switch_unlocked()) and use this to avoid dropping the scheduler lock and having the scheduler retake the same lock again. Add a better way of detecting if a low-level lock is in use. When switching out a thread due to blocking in the UTS, don't switch to the KSE's scheduler stack only to switch back to another thread. If possible switch to the new thread directly from the old thread and avoid the overhead of the extra context switch. Check for pending signals on a thread when entering the scheduler and add them to the threads signal frame. This includes some other minor signal fixes. Most of this was a joint effor between davidxu and myself. Reviewed by: davidxu Approved by: re@ (blanket for libpthread)
* Create the thread signal lock as a KSE lock (as opposed todeischen2003-04-291-18/+19
| | | | | | | | | | | | a thread lock). Better protect access to thread state while searching for threads to handle a signal. Better protect access to process pending signals while processing a thread in sigwait(). Submitted by: davidxu
* o Don't add a scope system thread's KSE to the list of availabledeischen2003-04-281-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | KSEs when it's thread exits; allow the GC handler to do that. o Make spinlock/spinlock critical regions. The following were submitted by davidxu o Alow thr_switch() to take a null mailbox argument. o Better protect cancellation checks. o Don't set KSE specific data when creating new KSEs; rely on the first upcall of the KSE to set it. o Add the ability to set the maximum concurrency level and do this automatically. We should have a way to enable/disable this with some sort of tunable because some applications may not want this to be the default. o Hold the scheduling lock across thread switch calls. o If scheduling of a thread fails, make sure to remove it from the list of active threads. o Better protect accesses to a joining threads when the target thread is exited and detached. o Remove some macro definitions that are now provided by <sys/kse.h>. o Don't leave the library in threaded mode if creation of the initial KSE fails. o Wakeup idle KSEs when there are threads ready to run. o Maintain the number of threads active in the priority queue.
* Revamp libpthread so that it has a chance of working in an SMPdeischen2003-04-181-3/+127
| | | | | | | | | | | | | | | | | | | environment. This includes support for multiple KSEs and KSEGs. The ability to create more than 1 KSE via pthread_setconcurrency() is in the works as well as support for PTHREAD_SCOPE_SYSTEM threads. Those should come shortly. There are still some known issues which davidxu and I are working on, but it'll make it easier for us by committing what we have. This library now passes all of the ACE tests that libc_r passes with the exception of one. It also seems to work OK with KDE including konqueror, kwrite, etc. I haven't been able to get mozilla to run due to lack of java plugin, so I'd be interested to see how it works with that. Reviewed by: davidxu
* Add the 'restrict' type qualifier to the prototypes of `sigaction',robert2002-10-021-1/+1
| | | | | | `sigprocmask', `sigaltstack', and `sigwait' as well as to the prototypes of the apparantly unimplemented functions `sigtimedwait' and `sigwaitinfo'. This complies with IEEE Std 1003.1-2001.
* Make libpthread KSE aware.mini2002-09-161-125/+3
| | | | | Reviewed by: deischen, julian Approved by: -arch
* Make the changes needed for libpthread to compile in its new home.mini2002-09-161-1/+1
| | | | | | | | The new libpthread will provide POSIX threading support using KSE. These files were previously repo-copied from src/lib/libc_r. Reviewed by: deischen Approved by: -arch
* To be consistent, use the __weak_reference macro from <sys/cdefs.h>deischen2001-04-101-1/+1
| | | | | | instead of #pragma weak to create weak definitions. Suggested by: bde
* Add weak definitions for wrapped system calls. In general:deischen2001-01-241-11/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | _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
* Make pthread_kill() know about temporary signal handlers installeddeischen2000-10-251-3/+5
| | | | | | | 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]).
* Implement zero system call thread switching. Performance ofdeischen2000-10-131-6/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* If multiple threads are blocked in sigwait() for the same signal that doesjasone2000-06-271-4/+27
| | | | | | | | | | | | | | | 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
* Simplify sytem call renaming. Instead of _foo() <-- _libc_foo <-- foo(),jasone2000-01-271-0/+1
| | | | | | | | | | | | | | | | | 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
* Change signal handling to conform to POSIX specified semantics.deischen1999-12-041-2/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before this change, a signal was delivered to each thread that didn't have the signal masked. Signals also improperly woke up threads waiting on I/O. With this change, signals are now handled in the following way: o If a thread is waiting in a sigwait for the signal, then the thread is woken up. o If no threads are sigwait'ing on the signal and a thread is in a sigsuspend waiting for the signal, then the thread is woken up. o In the case that no threads are waiting or suspended on the signal, then the signal is delivered to the first thread we find that has the signal unmasked. o If no threads are waiting or suspended on the signal, and no threads have the signal unmasked, then the signal is added to the process wide pending signal set. The signal will be delivered to the first thread that unmasks the signal. If there is an installed signal handler, it is only invoked if the chosen thread was not in a sigwait. In the case that multiple threads are waiting or suspended on a signal, or multiple threads have the signal unmasked, we wake up/deliver the signal to the first thread we find. The above rules still apply. Reported by: Scott Hess <scott@avantgo.com> Reviewed by: jb, jasone
* add pthread_cancel, obtained from OpenBSD.alfred1999-11-281-0/+3
| | | | | | | | | | | | | | eischen (Daniel Eischen) added wrappers to protect against cancled threads orphaning internal resources. the cancelability code is still a bit fuzzy but works for test programs of my own, OpenBSD's and some examples from ORA's books. add readdir_r to both libc and libc_r add some 'const' attributes to function parameters Reviewed by: eischen, jasone
* Add the proper headers so that the SIGNOTEMPTY and SIGSETANDmarcel1999-09-301-0/+2
| | | | macros are defined.
* sigset_t change (part 5 of 5)marcel1999-09-291-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ----------------------------- Most of the userland changes are in libc. For both the alpha and the i386 setjmp has been changed to accomodate for the new sigset_t. Internally, libc is mostly rewritten to use the new syscalls. The exception is in compat-43/sigcompat.c The POSIX thread library has also been rewritten to use the new sigset_t. Except, that it currently only handles NSIG signals instead of the maximum _SIG_MAXSIG. This should not be a problem because current applications don't use any signals higher than NSIG. There are version bumps for the following libraries: libdialog libreadline libc libc_r libedit libftpio libss These libraries either a) have one of the modified structures visible in the interface, or b) use sigset_t internally and may cause breakage if new binaries are used against libraries that don't have the sigset_t change. This not an immediate issue, but will be as soon as applications start using the new range to its fullest. NOTE: libncurses already had an version bump and has not been given one now. NOTE: doscmd is a real casualty and has been disconnected for the moment. Reconnection will eventually happen after doscmd has been fixed. I'm aware that being the last one to touch it, I'm automaticly promoted to being maintainer. According to good taste this means that I will receive a badge which either will be glued or mechanically stapled, drilled or otherwise violently forced onto me :-) NOTE: pcvt/vttest cannot be compiled with -traditional. The change cause sys/types to be included along the way which contains the const and volatile modifiers. I don't consider this a solution, but more a workaround.
* $Id$ -> $FreeBSD$peter1999-08-281-1/+1
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* Add RCS IDs to those files without them.deischen1999-08-051-2/+2
| | | | | | | Fix copyrights (s/REGENTS/AUTHOR). Suggested by: tg Approved by: jb
* In the words of the author:jb1999-06-201-15/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* [ The author's description... ]jb1999-03-231-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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.
* Implementation of an additional state called SIGWAIT (with the previousjb1998-09-301-13/+33
| | | | | | one renamed to SIGSUSPEND) to fix sigwait(). Submitted by: Daniel M. Eischen <eischen@vigrid.com>
* Fix for sigwait problem.jb1998-08-251-13/+61
| | | | | Submitted by: Daniel M. Eischen <eischen@vigrid.com> PR: misc/7039
* Change signal model to match POSIX (i.e. one set of signal handlersjb1998-04-291-9/+0
| | | | | | | | | | | | | | | | | | | | 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!
* Submitted by: John Birrelljulian1997-02-051-0/+73
uthreads update from the author.
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