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Date:   Thu, 4 Apr 2019 11:38:59 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Juergen Gross <jgross@suse.com>
Cc:     Alex Kogan <alex.kogan@oracle.com>,
        Waiman Long <longman@redhat.com>, linux@armlinux.org.uk,
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        rahul.x.yadav@oracle.com
Subject: Re: [PATCH v2 3/5] locking/qspinlock: Introduce CNA into the slow
 path of qspinlock
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On Thu, Apr 04, 2019 at 07:05:24AM +0200, Juergen Gross wrote:

> Without PARAVIRT_SPINLOCK this would be just an alternative() then?

That could maybe work yes. This is all early enough.

> Maybe the resulting code would be much more readable if we'd just
> make PARAVIRT_SPINLOCK usable without the other PARAVIRT hooks? So
> splitting up PARAVIRT into PARAVIRT_GUEST (timer hooks et al) and
> the patching infrastructure, with PARAVIRT_GUEST and PARAVIRT_SPINLOCK
> selecting PARAVIRT, and PARAVIRT_XXL selecting PARAVIRT_GUEST.

Well, ideally we'll get static_call() sorted and use that.