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.
When creating a new drive, if the drive already has a vinum label,
and name doesn't match the specified drive, do it anyway if the
'force' flag is specified.
Continually-tripped-over-by: Karl Pielorz <kpielorz@tdx.co.uk>
Update information about partition type for Vinum drives. They
*should* be of type 'vinum', but currently we still accept (and
complain about) partitions of type 'unused'. At a later date, only
'vinum' will be accepted.
Threatened-since: over a year
Semantics:
When creating a new drive, if the drive already has a vinum label,
and name doesn't match the specified drive, do it anyway if the
'force' flag is specified.
Continually-tripped-over-by: Karl Pielorz <kpielorz@tdx.co.uk>
remove the splbio() around the call to launch read requests.
launch_requests:
Move the splbio() protection outside the entire launch_loop. The
previous location was causing problems with IDE drives, where the
call to the strategy routine often did not complete until after
complete_rqe deallocated the request structure.
Solution-independently-found-by: Russell Neeper <r-neeper@tamu.edu>
Problem-reported-by: Vallo Kallaste <vallo@matti.ee>
John Saunders <john@nlc.net.au>
Bernd Walter <ticso@cicely.de> (maybe)
Check for partition types FS_VINUM and FS_UNUSED. Accept both, but
complain about FS_UNUSED. At a later date, only FS_VINUM will be
accepted.
Threatened-since: over a year
Add a flag `force' (VF_FORCECONFIG) to force name changes of
existing drives.
config_drive:
If the drive already has a vinum label, and name doesn't match the
specified drive, do it anyway if the 'force' flag is specified.
finish_config:
Reset the `force' flag.
Continually-tripped-over-by: Karl Pielorz <kpielorz@tdx.co.uk>
give_sd_to_drive:
If the drive is down, take the subdisk down and don't try to fix
things.
update_plex_config:
Don't try to update the config parameters of a plex which isn't
fully configured (state plex_init or plex_unallocated).
Correctly calculate the amount to trim off a striped or RAID-5 plex
whose size is not a multiple of the stripe size.
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.
/usr/sbin/sysctl -> ${DESTDIR}/sbin/sysctl in some versions of 2.2,
and this link was broken if DESTDIR was set.
Added a SYMLINKS macro. This works the same as LINKS, except it
creates symlinks and the linked-to pathname may be relative. This
is more flexible than LN_FLAGS, since it supports installing
symlinks independently of hard links.
Use `ln -f[s] ...' instead of `rm -f ...; ln [-s] ...' for LINKS and
SYMLINKS. This is equivalent if the target is neither a directory nor
a symlink to a directory.
PR: 8279
so that dumps are treated by dump -w as having been done on midnight
of the day they were actually run. This makes dump -w behave as
expected for regularly scheduled daily dumps - if they all run the
same day. It makes dump -w behave strangely if you dump late in the
day and check again after midnight, but that is the lesser of two
evils.
Submitted by: Mike Meyer <mwm@phone.net>
PR: 9429
Remove more (redundant) map timestamp increments from properly
synchronized routines. (Changed: vm_map_entry_link, vm_map_entry_unlink,
and vm_map_pageable.)
Micro-optimize vm_map_entry_link and vm_map_entry_unlink, eliminating
unnecessary dereferences. At the same time, converted them from macros
to inline functions.
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
