Commit Graph

11 Commits

Author SHA1 Message Date
John Birrell
b847980f15 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.  I found this useful, but we can
    get rid of it if you want.

Submitted by: Dan Eischen <eischen@vigrid.com>
1999-03-23 05:11:30 +00:00
Eivind Eklund
07bab7c6a4 Add support for pthread_mutexattr_settype(). As a side effect of
testing this, fix MUTEX_TYPE_COUNTING_FAST.  Recursive locks now work.
1998-11-28 23:52:58 +00:00
Alexander Langer
c0e366326f Implement pthread read/write locks as defined by Version 2 of the Single
UNIX Specification.

As with our standard mutexes, process shared locks are not supported at
this time.
1998-09-07 19:01:43 +00:00
John Birrell
edb4b26f50 Add static initializer defines as specified by POSIX. 1998-04-04 10:59:42 +00:00
Alexander Langer
372787c102 Changed pthread_detach to conform to POSIX, i.e. the single argument
provided is of type pthread_t instead of pthread_t *.

PR:		4320

Return EINVAL instead of ESRCH if attempting to detach an already
detached thread.
1997-12-25 05:07:20 +00:00
Bruce Evans
89ee8ac3d6 Fixed missing __P() to complete the K&R support in this header. 1997-05-07 00:58:23 +00:00
Alexander Langer
b7fee247fd Comment out _POSIX_THREAD_PRIORITY_SCHEDULING since it's not supported
at this time.

Reviewed by:	John Birrell <jb@cimlogic.com.au>
1997-03-04 01:30:50 +00:00
Julian Elischer
c840cec7c5 Submitted by: John Birrell
uthreads update from the author.
1997-02-05 23:26:09 +00:00
Jeffrey Hsu
9362f73db8 Moved pthread_mutexattr_default inside #ifndef PTHREAD_KERNEL now that
we use it in the uthreads implementation.
Moved enum pthread_mutextype here from libc_r/uthread/pthread_private.h.
Change prototype for pthread_getspecific().
1996-11-11 09:19:54 +00:00
Julian Elischer
0f7d684755 Submitted by: John Birrell <cimaxp1!jb@werple.net.au>
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.
1996-08-20 08:22:01 +00:00
Julian Elischer
2c2eb19365 Submitted by: john birrel
Obtained from: uthread package

thrreads definitions
1996-01-22 00:24:56 +00:00