On Wed, 25 Oct 2023 10:53:38 -0400
Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx> wrote:
> I don't have an informed opinion on whether the proposed heuristic is a
> good idea or not, but it should definitely be implemented as an
If you want to get an informed opinion, you can start here: ;-)
Thomas's first reply that had me think about this solution:
https://lore.kernel.org/lkml/87cyyfxd4k.ffs@tglx/
My reply that started it:
https://lore.kernel.org/lkml/20231024103426.4074d319@xxxxxxxxxxxxxxxxxx/
> extension to rseq as suggested by Peter. I've even made the whole rseq
> ABI extensible to accommodate those additional use-cases.
>
> In the initial rounds of rseq implementation, I even called rseq "kTLS"
> because I expected it to be extended and eventually become an ABI that
> contains various per-thread fields which are shared between kernel and
> userspace.
>
> So don't let the specific naming of the rseq system call stop you from
> extending it for other purposes when per-thread shared memory between
> kernel and userspace is needed. Setting up various per-thread areas like
> this on thread creation is not free: it requires additional system calls
> on thread creation. It really makes no sense to have more than one.
Thanks for the feedback Mathieu. This may indeed be the interface I am
looking for.
-- Steve
