[Crash-utility] RFC: Improving crash's search speed

[Dave Anderson]

----- Original Message -----
> On Wed, 2011-01-26 at 14:47 +0000, Dave Anderson wrote:
> 
> >
> > Anyway, I'm thinking now that "search" should be reworked to add
> > these
> > new variants:
> >
> >   search -K unity-mapped kernel only
> >   search -V vmalloc memory only
> >   search -M kernel text/data mapped region (arch-dependent)
> >   search -p physical memory
> >
> > and leave the current mechanism as it is now:
> >
> >   search -u user-space of current context
> >   search -k all of kernel virtual space
> >
> > where "search -k" would be equivalent to "search -KVM".
> >
> > Let me tinker around with this -- thanks for the suggestion
> > (and the inadvertant x86_64 bug report).
> 
> Well, the real reason I started here was that I'm trying to implement my
> string searcher, and when I tested the first prototype in crash, it took
> forever compared to my physical page searcher.
> 
> (Basically a bunch of strncmp's starting on each byte, with extra
> searches at the start of the page for "last half or more" and at the end
> for "first half or more", since it's hard to track the virtual page
> layout to search for strings across page boundaries.)

Hmmm, string search -- that's pretty cool...  I'll let you work on that.

I've pretty much got -p working OK, and next I'll plug in the -KVM restrictors. 
 
> Today I'm trying to find out why parse_line() is messing up when given
> more than one string in ""'s.

Not sure I understand how you can do that, but don't let me interfere...

Thanks,
  Dave