Subject: [PATCH Shepherd 0/2] Use 'signalfd' on GNU/Linux

From: Ludovic Courtès <[email-masked]>
Date: Sun, 24 May 2020 16:27:00 +0200

Hello!

This patch series allows shepherd to use ‘signalfd’ on GNU/Linux.
It allows us to avoid race conditions related to signal delivery,
which in turn means we can pass an infinite timeout to ‘select’,
and thus increase battery life.

More generally, it’s a way to structure the code around the event
loop.  The next step will be to make the code entirely reactive,
so we can have things like socket activation, being able to start
services that don’t depend on one another concurrently, and all that.
(This is actually also be possible without ‘signalfd’ but it’s more
consistent and robust to have everything visible to ‘select’.)

Thoughts?

I guess the main question is: can it go into 0.8.1, which we outta
release soon due to <https://issues.guix.gnu.org/40981>.  I’d say
“yes”, but I’ll be even more confident if others take a look.  :-)

Ludo’.

Ludovic Courtès (2):
  system: Add support for 'signalfd'.
  shepherd: Use 'signalfd' when possible.

 configure.ac                   | 18 +++++++++
 modules/shepherd.scm           | 73 ++++++++++++++++++++++++++++++----
 modules/shepherd/service.scm   | 19 +++++----
 modules/shepherd/system.scm.in | 65 ++++++++++++++++++++++++++++++
 4 files changed, 161 insertions(+), 14 deletions(-)

-- 
2.26.2