Re: L4Env

[Niels Möller]

Lars Reuther <address@hidden> writes:

> Our memory management consists of two main elements, dataspace
> managers and region mappers. Dataspaces are container for any kind of
> memory (files, anonymous memory, ...). They are managed by dataspace
> managers (e.g. file systems, anonymous memory managers,
> ...). Dataspaces can be attached to regions of the address space of a
> L4 task. 
> Region mappers are pager threads, usually we use one region mapper in
> each L4 task which is the pager for all other threads of that
> task. The region mapper doesn't resolve the pagefault itself, instead
> it looks up the dataspace which is attached to the pagefault address
> and calls the dataspace manager which manages that dataspace to map
> the appropriate page. 

Sounds cute. But one question: What happes if the task is completely
swapped out? I.e. when none of the pages in it's dataspaces are
assigned to physical management? How can it get swapped in again? I
guess you're keeping the code and data needed by the pager thread in
physical memory, somehow. The code pages can be shared between tasks,
I guess.

Regards,
/Niels