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Date: Fri, 16 Jun 2017 11:24:07 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Nicholas Piggin <npiggin@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>, Babu Moger <babu.moger@oracle.com>,
 linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org
Subject: Re: [PATCH v4 4/5] watchdog: provide watchdog_reconfigure() for
 arch watchdogs
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On Fri, 16 Jun 2017 16:57:14 +1000 Nicholas Piggin <npiggin@gmail.com> wrote:

> After reconfiguring watchdog sysctls etc., architecture specific
> watchdogs may not get all their parameters updated.
> 
> watchdog_reconfigure() can be implemented to pull the new values
> in and set the arch NMI watchdog.
> 

I'll update the title and changelog to say "watchdog_nmi_reconfigure".

> --- a/kernel/watchdog.c
> +++ b/kernel/watchdog.c
> @@ -123,6 +123,11 @@ void __weak watchdog_nmi_disable(unsigned int cpu)
>  {
>  }
>  
> +void __weak watchdog_nmi_reconfigure(void)
> +{
> +}

Can we please get some documentation in here describing what it's for? 
How arch maintainers might use this?  When and why it is called, what
it must do?  etc.