On Wed, Jun 5, 2019 at 8:58 AM Oleg Nesterov <oleg@redhat.com> wrote:
>
> To simplify the review, please see the code with this patch applied.
> I am using epoll_pwait() as an example because it looks very simple.

I like it.

However.

I think I'd like it even more if we just said "we don't need
restore_saved_sigmask AT ALL".

Which would be fairly easy to do with something like the attached...

(Yes, this only does x86, which is a problem, but I'm bringing this up
as a RFC..)

Is it worth another TIF flag? This sure would simplify things, and it
really fits the concept too: this really is a do_signal() issue, and
fundamentally goes together with TIF_SIGPENDING.

                Linus