Re: Stack base and thread-specific data

[Igor Khavkine]

On Wed, Aug 08, 2001 at 05:23:11PM -0400, Roland McGrath wrote:
> You misunderstand the nature of the plan to use segment registers.
> Please read the linuxthreads code.

I can't see what I was misunderstanding. I've looked through
the linuxthreads code and it does exactly what I was expecting
it to do. For each thread it adds an entry to the LDT, then loads
that selector into %gs and uses %gs:0 as the address to access
it's per-thread data structure.

My only concern was that the limited number of available selectors
(2^14 minus a few already use ~ 16000) would be smaller then
the actual number of concurrent threads that Mach supports. But
that fear is baseless since right now Mach only supports up
to 1024 concurrent threads.

Igor