Re: [patch] tls-2.5.30-A1

Ingo Molnar
2002-08-07T22:51:54Z

On 8 Aug 2002, Luca Barbieri wrote:

> > I would suggest:
> > - move all kernel-related (and thus non-visible to user space) segments
> > up, and make the cacheline optimizations _there_.
> Done.
> > - keep the TLS entries contiguous, and make sure that segment 0040 (ie
> > GDT entry #8) is available to a TLS entry, since if I remember
> > correctly, that one is also magical for old Windows binaries for all
> > the wrong reasons (ie it was some system data area in DOS and in
> > Windows 3.1)
> Done. Segment 0x40 set to CPL 3.
> > - and for cleanliness bonus points: make the regular user data segments
> > just another TLS segment that just happens to have default values. If
> > the user wants to screw with its own segments, let it.
> Bad idea: makes task switch slower without any practical advantage.
> The user may load a TLS or LDT selector in %ds to get the same effect.

your patch looks good to me - as long as we want to keep those 2 TLS
entries and nothing more. (which i believe we want.) If even more TLS
entries are to be made possible then a cleaner TLS enumeration interface
has to be used like Christoph mentioned - although i dont think we really
want that, 3 or more entries would be a stretch i think.

Ingo