Re: [PATCH v3 3/3] checkpatch: add virt barriers

From: "Michael S. Tsirkin" <mst@redhat.com>
To: Julian Calaby <julian.calaby@gmail.com>
Cc: Joe Perches <joe@perches.com>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	Andy Whitcroft <apw@canonical.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Arnd Bergmann <arnd@arndb.de>,
	linux-arch@vger.kernel.org,
	Andrew Cooper <andrew.cooper3@citrix.com>,
	virtualization@lists.linux-foundation.org,
	Stefano Stabellini <stefano.stabellini@eu.citrix.com>,
	Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@elte.hu>,
	"H. Peter Anvin" <hpa@zytor.com>,
	David Miller <davem@davemloft.net>,
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	linux-s390@vger.kernel.org,
	sparclinux <sparclinux@vger.kernel.org>,
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	Russell King - ARM Linux <linux@arm.linux.org.uk>
Subject: Re: [PATCH v3 3/3] checkpatch: add virt barriers
Date: Mon, 11 Jan 2016 12:56:35 +0200	[thread overview]
Message-ID: <20160111124509-mutt-send-email-mst@redhat.com> (raw)
In-Reply-To: <CAGRGNgU7=vNXZbgSwLs+bBueX1+rKACCRMi74hM+jP8MaX+-WA@mail.gmail.com>

On Mon, Jan 11, 2016 at 09:40:18PM +1100, Julian Calaby wrote:
> Hi Michael,
> 
> On Mon, Jan 11, 2016 at 9:35 PM, Michael S. Tsirkin <mst@redhat.com> wrote:
> > On Sun, Jan 10, 2016 at 02:52:16PM -0800, Joe Perches wrote:
> >> On Mon, 2016-01-11 at 09:13 +1100, Julian Calaby wrote:
> >> > On Mon, Jan 11, 2016 at 6:31 AM, Michael S. Tsirkin <mst@redhat.com> wrote:
> >> > > Add virt_ barriers to list of barriers to check for
> >> > > presence of a comment.
> >> []
> >> > > diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> >> []
> >> > > @@ -5133,7 +5133,8 @@ sub process {
> >> > >                 }x;
> >> > >                 my $all_barriers = qr{
> >> > >                         $barriers|
> >> > > -                       smp_(?:$smp_barrier_stems)
> >> > > +                       smp_(?:$smp_barrier_stems)|
> >> > > +                       virt_(?:$smp_barrier_stems)
> >> >
> >> > Sorry I'm late to the party here, but would it make sense to write this as:
> >> >
> >> > (?:smp|virt)_(?:$smp_barrier_stems)
> >>
> >> Yes.  Perhaps the name might be better as barrier_stems.
> >>
> >> Also, ideally this would be longest match first or use \b
> >> after the matches so that $all_barriers could work
> >> successfully without a following \s*\(
> >>
> >> my $all_barriers = qr{
> >>       (?:smp|virt)_(?:barrier_stems)|
> >>       $barriers)
> >> }x;
> >>
> >> or maybe add separate $smp_barriers and $virt_barriers
> >>
> >> <shrug>  it doesn't matter much in any case
> >
> > OK just to clarify - are you OK with merging the patch as is?
> > Refactorings can come as patches on top if required.
> 
> I don't really care either way, I was just asking if it was possible.
> If you don't see any value in that change, then don't make it.
> 
> Thanks,
> 
> -- 
> Julian Calaby
> 
> Email: julian.calaby@gmail.com
> Profile: http://www.google.com/profiles/julian.calaby/

OK, got it, thanks.

I will rename smp_barrier_stems to barrier_stems since
this doesn't need too much testing.

I'd rather keep the regex code as is since changing it requires
testing.  I might play with it some more in the future
but I'd like to merge it in the current form to help make
sure __smp barriers are not misused.

I'll post v4 now - an ack will be appreciated.
-- 
MST