Re: [RFC PATCH 0/9] Introduce housekeeping subsystem
From: Chris Metcalf
Date: Fri Jul 21 2017 - 15:48:38 EST
On 7/21/2017 9:21 AM, Frederic Weisbecker wrote:
I'm leaving for two weeks so this is food for thoughts in the meantime :)
We have a design issue with nohz_full: it drives the isolation features
through the *housekeeping*() functions: kthreads, unpinned timers,
watchdog, ...
But things should work the other way around because the tick is just an
isolation feature among others.
So we need a housekeeping subsystem to drive all these isolation
features, including nohz full in a later iteration. For now this is a
basic draft. In the long run this subsystem should also drive the tick
offloading (remove residual 1Hz) and all unbound kthreads.
git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git
nohz/0hz
HEAD: 68e3af1de5db228bf6c2a5e721bce59a02cfc4e1
For the series:
Reviewed-by: Chris Metcalf <cmetcalf@xxxxxxxxxxxx>
I spotted a few typos that you should grep for and fix for your next
version:
"watchog", "Lets/lets" instead of "Let's/let's", "overriden" (should
have two d's).
The new housekeeping=MASK boot option seems like it might make it a little
irritating to specify nohz_full=MASK as well. I guess if setting
NO_HZ_FULL_ALL
implied "all but housekeeping", it becomes a reasonably tidy solution.
To make
this work right you might have to make the housekeeping option early_param
instead so its value is available early enough.
--
Chris Metcalf, Mellanox Technologies
http://www.mellanox.com