Re: [PATCH 3/3] x86, extable: Handle early exceptions

Tony Luck
2012-04-19T22:47:30Z

On Thu, Apr 19, 2012 at 3:16 PM, H. Peter Anvin <hpa@zytor.com> wrote:
> One thing that probably would give more of a boost is to use a rbtree or
> similar structure to figure out *which* extable (if any) we should be
> looking at; right now it looks like we linearly walk the modules, and
> don't even look to see if we are inside that module before we do a
> bsearch in that module's extable...

How many entries are in the extable for a typical module? Perhaps it might
make sense to bundle them all into one sorted combined table? Of course
you would have to have a way to squeeze them back out of the combined
table at module unload time.

This moves the cost to module load/unload time ... which is hopefully rare
compared to table lookup.

-Tony