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.
ifdefs are too ugly for this to be much of a simplification. The
existence tests are even uglier now. Note that the previous commit
was not submitted by me. It missed the point and just added a second
layer of unused removals.
Fixed hard-coded "libcrypt"s. The LCRYPTBASE macro mainly makes
things hard to read, but use it while we have it.
which ones cause us to fail. Now all open errors on the databse file
will cause the next file in the list to be tried.
Submitted by: Arne Henrik Juul <arnej@math.ntnu.no>
PR: 4585
levels (-O3 and above) won't remove essential code. Many thanks
to Dmitrij Tejblum <dima@tejblum.dnttm.rssi.ru> for pointing out
that it was the optimizer's removal of this code that caused make
world with -O3 to break. With this change, make buildworld now
completes.
shared library when invoking global constructors and destructors.
For constructors, the object files used to be processed from first
to last; now they're done from last to first. (Destructors are done
in the opposite order, as required by the C++ standard.) This makes
us consistent with standard gcc and egcs compilers. It also
eliminates ordering differences between dynamic and static
executables.
Bump the value of __FreeBSD_version to 400002 to reflect this
change.
C function so the compiler won't try to emit line numbers for it
with "-g", breaking the build. This has the nice side-effect of
making crtbegin.o and crtbeginS.o a little bit smaller.
Remove "-Wno-unused" from the Makefile. Replace it with "__unused"
on particular function and variable declarations.
compiling, since <stdio.h> correctly doesn't declare off_t although
the pseudo-prototypes for the new fseeko() and ftello() functions
use it. Handle this like the corresponding problem for va_list
versus the vprintf() family.
Fixed some English errors.
request for it something like it. It was poorly worded and too
far from both POSIX wording and normal (mal)practice by referring to
sysconf(_SC_NGROUPS_MAX) instead of {NGROUPS_MAX} or NGROUPS. POSIX.1
uses curly braces to mark up "symbolic constants or limits [that may
be] defined in certain headers". Since we don't document this markup,
don't use it. Just use NGROUPS_MAX.
so that non-sloppy applications can call it without using disgusting
casts to avoid warnings. The 4th arg is sort of varargs -- it must
sometimes represent a filename, sometimes a struct pointer, and is
sometimes unused. The arg type is still caddr_t in the kernel.
Obtained from: mostly from NetBSD
and SHA-1 when OBJFORMAT is not ELF. Add a warning to the man page
about how SHA-1 uses bswapl, which will trap on 80386es (and the kernel
should, but doesn't currently, emulate).
build, but broke while doing the aout legacy build). Now using
.p2align instead of .align. Fixes broken buildworld.
Submitted by: John Polstra
Reviewed by: John Polstra
- Transparent proxying support added.
- PPTP redirecting support added based on patches
contributed by Dru Nelson <dnelson@redwoodsoft.com>.
Submitted by: Charles Mott <cmott@srv.net>
