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Date:   Thu, 27 Jun 2019 15:08:59 -0300
From:   Marcelo Tosatti <mtosatti@redhat.com>
To:     Doug Smythies <dsmythies@telus.net>
Cc:     "'Paolo Bonzini'" <pbonzini@redhat.com>,
        "'Radim Krcmar'" <rkrcmar@redhat.com>,
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Subject: Re: [patch 3/5] cpuidle: add haltpoll governor
Message-ID: <20190627180856.GA27865@amt.cnet>
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On Thu, Jun 20, 2019 at 05:34:46PM -0700, Doug Smythies wrote:
> Hi,
> 
> I tried your patch set, but only to check
> that they didn't cause any regression for situations
> where idle state 0 (Poll) is used a lot (teo governor).
> 
> They didn't (my testing was not thorough).
> 
> I do not know if the below matters or not.
> 
> On 2019.06.13 15:46 Marcelo Tosatti wrote:
> 
> ... [snip] ...
> 
> > Index: linux-2.6.git/Documentation/virtual/guest-halt-polling.txt
> > ===================================================================
> > --- /dev/null	1970-01-01 00:00:00.000000000 +0000
> > +++ linux-2.6.git/Documentation/virtual/guest-halt-polling.txt	2019-06-13 18:16:22.414262777 -0400
> > @@ -0,0 +1,79 @@
> > +Guest halt polling
> > +==================
> > +
> > +The cpuidle_haltpoll driver, with the haltpoll governor, allows
> > +the guest vcpus to poll for a specified amount of time before
> > +halting.
> > +This provides the following benefits to host side polling:
> > +
> > +	1) The POLL flag is set while polling is performed, which allows
> > +	   a remote vCPU to avoid sending an IPI (and the associated
> > + 	   cost of handling the IPI) when performing a wakeup.
>    ^
>    |_ While applying the patches, git complains about this space character before the TAB.
> 
> It also complains about a few patches with a blank line before EOF.
> 
> ... Doug

Hi Doug,

Will fix those, thanks.