Subject: Re: [RFC PATCH 0/9] Introduce housekeeping subsystem
To: Frederic Weisbecker <fweisbec@gmail.com>,
        LKML <linux-kernel@vger.kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Luiz Capitulino <lcapitulino@redhat.com>,
        Christoph Lameter <cl@linux.com>,
        "Paul E . McKenney" <paulmck@linux.vnet.ibm.com>,
        Ingo Molnar <mingo@kernel.org>, Mike Galbraith <efault@gmx.de>,
        Rik van Riel <riel@redhat.com>, Wanpeng Li <kernellwp@gmail.com>
References: <1500643290-25842-1-git-send-email-fweisbec@gmail.com>
From: Chris Metcalf <cmetcalf@mellanox.com>
Message-ID: <f50f9cb3-a3ea-3e2e-9b0a-ebb9af900568@mellanox.com>
Date: Fri, 21 Jul 2017 15:48:16 -0400
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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@mellanox.com>

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