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* add pthread_cancel, obtained from OpenBSD.alfred1999-11-281-7/+20
| | | | | | | | | | | | | | 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
* sigset_t change (part 5 of 5)marcel1999-09-291-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ----------------------------- 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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* handle under/overflow of time values in a more robust manner,alfred1999-08-191-3/+3
| | | | | | | | 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
* Add check for runnable threads before polling file descriptors.deischen1999-08-121-14/+16
| | | | Submitted by: tegge
* In the words of the author:jb1999-06-201-831/+650
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* Back out patch for cond_timedwait() bug from -current, since other changesjasone1999-05-081-10/+1
| | | | | | | have made the patch obsolete, as pointed out by Daniel Eischen <eischen@vigrid.com>. PR: bin/8872
* Apply patch included in bin/8872. This fixes a bug that occurs whenjasone1999-05-071-2/+11
| | | | | | | | pthread_cond_timedwait() times out. PR: bin/8872 Submitted by: Jason Evans <jasone@canonware.com> Reviewed by: David Schwartz <davids@webmaster.com>
* [ The author's description... ]jb1999-03-231-323/+296
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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.
* Close a window between unlocking a spinlock and changing the thread state.jb1998-11-151-1/+17
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* Fix some bugs in pthread scheduler:dt1998-10-091-6/+9
| | | | | | | | 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>
* Move the cleanup code that frees memory allocated for a dead thread fromjb1998-09-301-80/+2
| | | | | | | | | | | | | | 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.
* Removed unused variables.alex1998-09-071-2/+1
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* Fix the incremental priority increment.jb1998-04-301-2/+2
| | | | PR: bin/6467 Marino Ladavac <lada@pc8811.gud.siemens.at>
* Change signal model to match POSIX (i.e. one set of signal handlersjb1998-04-291-435/+35
| | | | | | | | | | | | | | | | | | | | 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!
* When in PS_SIGWAIT state, still call signal handlers and set errnojb1998-04-171-13/+2
| | | | to EINTR.
* Change the FILE locking to be by FILE, not by the underlying fd asjb1998-04-111-1/+4
| | | | | | | | | | | | | 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.
* Add FreeBSD/Alpha code to initialise a jmpbuf for a created thread.jb1998-03-091-4/+4
| | | | Change a bunch of __alpha references to __alpha__.
* Fixes from Jeremy Allison and Terry Lambert for pthreads:julian1998-02-131-1/+53
| | | | | | | | | | | | | | | | | | | | | specifically: uthread_accept.c: Fix for inherited socket not getting correct entry in pthread flags. uthread_create.c: Fix to allow pthread_t pointer return to be null if caller doesn't care about return. uthread_fd.c: Fix for return codes to be placed into correct errno. uthread_init.c: Changes to make gcc-2.8 thread aware for exception stack frames (WARNING: This is #ifdef'ed out by default and is different from the Cygnus egcs fix). uthread_ioctl.c: Fix for blocking/non-blocking ioctl. uthread_kern.c: Signal handling fixes (only one case left to fix, that of an externally sent SIGSEGV and friends - a fairly unusual case). uthread_write.c: Fix for lock of fd - ask for write lock, not read/write. uthread_writev.c: Fix for lock of fd - ask for write lock, not read/write. Pthreads now works well enough to run the LDAP and ACAPD(with the gcc 2.8 fix) sample implementations.
* Fix indentations. Sigh.jb1997-04-011-15/+17
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* Submitted by: John Birrelljulian1997-02-051-16/+55
| | | | uthreads update from the author.
* Remove now un-necessary FreeBSD specific code since our timespecnate1996-09-201-112/+0
| | | | | | structure now has the correct member names. Pointed out by: Peter Wemm
* Submitted by: John Birrell <cimaxp1!jb@werple.net.au>julian1996-08-201-1/+230
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Here are the diffs for libc_r to get it one step closer to P1003.1c These make most of the thread/mutex/condvar structures opaque to the user. There are three functions which have been renamed with _np suffixes because they are extensions to P1003.1c (I did them for JAVA, which needs to suspend/resume threads and also start threads suspended). I've created a new header (pthread_np.h) for the non-POSIX stuff. The egrep tags stuff in /usr/src/lib/libc_r/Makefile that I uncommented doesn't work. I think its best to delete it. I don't think libc_r needs tags anyway, 'cause most of the source is in libc which does have tags. also: Here's the first batch of man pages for the thread functions. The diff to /usr/src/lib/libc_r/Makefile removes some stuff that was inherited from /usr/src/lib/libc/Makefile that should only be done with libc. also: I should have sent this diff with the pthread(3) man page. It allows people to type make -DWANT_LIBC_R world to get libc_r built with the rest of the world. I put this in the pthread(3) man page. The default is still not to build libc_r. also: The diff attached adds a pthread(3) man page to /usr/src/share/man/man3. The idea is that without libc_r installed, this man page will give people enough info to know that they have to build libc_r.
* Reviewed by: julianjulian1996-01-221-0/+1581
Submitted by: john birrel One version of the pthreads library another will follow with differnt actions under some cases.. not QUITE complete
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