- It actually works this time, honest!
- Fine grained TLB shootdowns for SMP on i386. IPI's are very expensive,
so try and optimize things where possible.
- Introduce ranged shootdowns that can be done as a single IPI.
- PG_G support for i386
- Specific-cpu targeted shootdowns. For example, there is no sense in
globally purging the TLB cache for where we are stealing a page from
the local unshared process on the local cpu. Use pm_active to track
this.
- Add some instrumentation for the tlb shootdown code.
- Rip out SMP code from <machine/cpufunc.h>
- Try and fix some very bogus PG_G and PG_PS interactions that were bad
enough to cause vm86 bios calls to break. vm86 depended on our existing
bugs and this was the cause of the VESA panics last time.
- Fix the silly one-line error that caused the 'panic: bad pte' last time.
- Fix a couple of other silly one-line errors that should have caused more
pain than they did.
Some more work is needed:
- pmap_{zero,copy}_page[_idle]. These can be done without IPI's if we
have a hook in cpu_switch.
- The IPI handlers need some cleanup. I have a bogus %ds load that can
be avoided.
- APTD handling is rather bogus and appears to be a large source of
global TLB IPI shootdowns for no really good reason.
I see speedups of between 1.5% and ~4% on buildworlds in a while 1 loop.
I expect to see a bigger difference when there is significant pageout
activity or the system otherwise has memory shortages.
I have backed out a few optimizations that I had been using over the last
few days in order to be a little more conservative. I'll revisit these
again over the next few days as the dust settles.
New option: DISABLE_PG_G - In case I missed something.
This is basically a ``C compilation'' of the former whereis.pl file,
employing the same algorithms, and aiming at being mostly
UI-compatible to the old (legally tainted) 4.3BSD whereis(1). In
comparision, the 4.4BSD-Lite version is just another variant of
which(1) only, where in particular the option to search for source
directories is sorely missing.
While i was at it, i added two more options which i contemplated doing
long since. -x will suppress the run of locate(1) to find sources
that could not be found otherwise, potentially saving a lot of time
(but obviously, risking to not find some sources that are well hidden
in the tree). -q will omit the leading name of the query, so in
particular, you can now do something like:
cd `whereis -qs ls`
I'd explicitly like to thank johan for his review which was quite a
bit more than an average review, including sending me a lot of diffs.
Reviewed by: johan