doesn't have to calculate it every call.
Rename `timer0_prescale' to `timer0_prescaler_count' and maintain it
correctly. Previously we lost a few 8253 cycles for every "prescaled"
clock interrupt, and the lossage grows rapidly at 16 KHz. Now we
only lose a few cycles for every standard clock interrupt.
Rename `*_divisor' to `*_max_count'.
Do the calculation of TIMER_DIV(rate) only once instead of 3 times each
time the rate is changed.
Don't allow preposterously large interrupt rates. Bug fixes elsewhere
should allow the system to survive rates that saturate the system, however.
Clean up declarations.
Include <machine/clock.h> to check our own declarations.
outside the critical region.
Make it work with 2.0. It wasn't designed to be called at splclock().
Make it work with prescaling. The overflow threshold was bogus.
Make it work for any HZ. Side effect of fixing prescaling.
Speed it up. Allocate registers better. Reduce multiplication and
division to multiplication and a shift. Speed is now 5-6 usec on a
486DX/33, was about 3 usec more.
Optimize for the non-pentium case. The pentium code got moved around
a bit and hasn't been tested.
Change #include's to 2.0 style.
for it is incomplete and buggy. There is no problem unless Xintr0()
is reentered or should be reentered, but high clock interrupt
frequencies for pcaudio cause Xintr0() to be reentered (or clock
ticks to be lost when Xintr0() should have been reentered but
wasn't), and we lose little by delaying the call to softclock().
Move declarations related to the clock driver to clock.h.
Move declarations related to the npx driver to npx.h.
Clean up the remaining declarations.
From: Chris Torek <torek@bsdi.com>
Here is a semi-official patch (apply to /usr/src/lib/libc/stdio/fseek.c,
rebuild libc, install). The current code fails when the seek:
- is optimized, and
- is to just past the end of the block currently in the buffer, and
- is followed by another seek with no intervening read operation, and
- the destination of subsequent seek is within the block left in the
buffer (seeking to the beginning of a block does not force a read,
so the buffer still contains the previous block)
so it is indeed rather obscure.
I may have a different `final' fix, as this one `loses' the buffer
contents on a seek that goes just past the end of the current block.
[Footnote: seeks are optimized only on read-only opens of regular
files that are buffered by the file's optimal I/O size. This is
what you get with fopen(path, "r") and no call to setvbuf().]
Obtained from: [ BSDI mailing list ]
have to write the text-file it will dump on you.
Stopped using cleartoeol in AskEm(), just as a test to see if the screen
looks more sane.
Added a attempted auto-recognition of /, swap and /usr for the first disk
where it looks sensible. Logic of this might need to be improved.
Made a "ShowFile()" which will not bomb/ignore you if the file isn't there.
/sbin/umount does not return the correct exit status due to incorrect
logic in its internals.
Further, because of the nature of the code, you *cannot* use it to
umount a directory from a union mountpoint. Well, you can sometimes,
it depends on if the directory is at the top of the union stack or not :)
Submitted by: njw@cs.city.ac.uk (Nick Williams)
Find enclosed a short bugfix to get the union filesystem up and running
in FreeBSD-current. We don't think we've got all the problems yet but
these fixes sort out the major ones (which mostly concert bad locking
of vnodes), no doubt we'll post others as necessary. Known problems
include the inability of the umount command (not the system call) to unmount
unions in certain circumstances (this is due the way "realpath" works),
and the failure of direntries to always get all available files in
unioned subdirectories. We are, as they say, working on it.
Submitted by: tim@cs.city.ac.uk (Tim Wilkinson)
