Finished the constant poisoning that was begun in rev.1.14. Consts
aren't very poisonous (or useful) unless -Wcast-qual is in CFLAGS,
and it isn't in the default CFLAGS.
type identification code out of machdep.c and into a new file of its
own. Hopefully other grot can be moved out of machdep.c as well
(by other people) into more descriptively-named files.
Testing with the high frequency of 20000 Hz (to find problems) only found
the problem that this frequency is too high for slow i386's.
Disable interrupts while setting the timer frequency. This was unnecessary
before rev.1.57 and forgotten in rev.1.57. The critical (i8254) interrupts
are disabled in another way at boot time but not in the sysctl to change
the frequency.
Fixed profiling of system times. It was pre-4.4Lite and didn't support
statclocks. System times were too small by a factor of 8.
Handle deferred profiling ticks the 4.4Lite way: use addupc_task() instead
of addupc(). Call addupc_task() directly instead of using the ADDUPC()
macro.
Removed vestigial support for PROFTIMER.
switch.s:
Removed addupc().
resourcevar.h:
Removed ADDUPC() and declarations of addupc().
cpu.h:
Updated a comment. i386's never were tahoe's, and the deferred profiling
tick became (possibly) multiple ticks in 4.4Lite.
Obtained from: mostly from NetBSD
multiplication in addupc() overflowed for addresses >= 256K, assuming
the usual profil(2) scale parameter of 0x8000. addupc() will go away
soon.
Submitted by: John Polstra <jdp@polstra.com>
is only used by the icu support modules and by a few drivers that know
too much about the icu (most only use it to convert `n' to `IRQn'). isa.h
is only used by ioconf.c and by a few drivers that know too much about
isa addresses (a few have to, because config is deficient).
enable flag instead of enable_intr() to restore it to its usual state.
getit() is only called from DELAY() so there is no point in optimising
its speed (this wasn't so clear when it was extern), and using
enable_intr() made it inconvenient to call DELAY() from probes that need
to run with interrupts disabled.
1) Make it much less likely to miss a wakeup in vm_page_free_wakeup
2) Create a new entry point into pmap: pmap_ts_referenced, eliminates
the need to scan the pv lists twice in many cases. Perhaps there
is alot more to do here to work on minimizing pv list manipulation
3) Minor improvements to vm_pageout including the use of pmap_ts_ref.
4) Major changes and code improvement to pmap. This code has had
several serious bugs in page table page manipulation. In order
to simplify the problem, and hopefully solve it for once and all,
page table pages are no longer "managed" with the pv list stuff.
Page table pages are only (mapped and held/wired) or
(free and unused) now. Page table pages are never inactive,
active or cached. These changes have probably fixed the
hold count problems, but if they haven't, then the code is
simpler anyway for future bugfixing.
5) The pmap code has been sorely in need of re-organization, and I
have taken a first (of probably many) steps. Please tell me
if you have any ideas.
All new code is "#ifdef PC98"ed so this should make no difference to
PC/AT (and its clones) users.
Ok'd by: core
Submitted by: FreeBSD(98) development team
It is called from copyin and copyout.
The new routine is conditioned on I586_CPU and I586_FAST_BCOPY, so you
need
options "I586_FAST_BCOPY"
(quotes essenstial) in your kernel config file.
Also, if you have other kernel types configured in your kernel, an
additional check to make sure it is running on a Pentium is inserted.
(It is not clear why it doesn't help on P6s, it may be just that the
Orion chipset doesn't prefetch as efficiently as Tritons and friends.)
Bruce can now hack this away. :)
alias `pcb_cr3' instead. That is still one alias too many, but is convenient
for me since I've replaced the tss in the pcb by a few scalar variables in
the pcb.
altfmt was abused to sometimes screw up the disassembly of the bytes
following unconditional jump instructions. Gas doesn't pad to a longword
boundary like the comment said - that is the programmer's responsibility.
queue in vm_fault.
Move the PG_BUSY in vm_fault to the correct place.
Remove redundant/unnecessary code in pmap.c.
Properly block on rundown of page table pages, if they are busy.
I think that the VM system is in pretty good shape now, and the following
individuals (among others, in no particular order) have helped with this
recent bunch of bugs, thanks! If I left anyone out, I apologize!
Stephen McKay, Stephen Hocking, Eric J. Chet, Dan O'Brien, James Raynard,
Marc Fournier.
some problems with the page-table page management code, since it can't
deal with the notion of page-table pages being paged out or in transit.
Also, clean up some stylistic issues per some suggestions from
Stephen McKay.
process during pmap_copy. This minimizes unnecessary swapping or creation of
swap space. If there is a hold_count flaw for page-table
pages, clear the page before freeing it to lessen the chance of a system
crash -- this is a robustness thing only, NOT a fix.
close some windows that are opened up by page table allocations. The
prefaulting code no longer uses hold counts, but now uses the busy
flag for synchronization.
ansi and traditional cpp.
The nesting rules of macros are different, which required some changes.
Use __CONCAT(x,y) instead of /**/.
Redo some comments to use /* */ rather than "# comment" because the ansi
cpp cares about those, and also cares about quote matching.
queue corruption problems, and to apply Gary Palmer's code cleanups.
David Greenman helped with these problems also. There is still
a hang problem using X in small memory machines.
comparing the PTD pointers, they needed to be masked by PG_FRAME, and
they weren't. Also, the "improved" non-386 code wasn't really an
improvement, so I simplified and fixed the code. This might have
caused some of the panics caused by the VM megacommit.
With this fix from Stephen, we are getting the target fork performance
that I have been trying to attain: P5-166, before the mega-commit: 700-800usecs,
after: 600usecs, with Stephen's fix: 500usecs!!! Also, this could be the
solution of some strange panic problems...
Reviewed by: dyson@freebsd.org
Submitted by: Stephen McKay <syssgm@devetir.qld.gov.au>
