Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Wed, 20 Jul 2022 11:23:15 +0200
From:   Heiko Carstens <hca@linux.ibm.com>
To:     Alexander Gordeev <agordeev@linux.ibm.com>
Cc:     Jason Wang <wangborong@cdjrlc.com>, svens@linux.ibm.com,
        gor@linux.ibm.com, borntraeger@linux.ibm.com,
        linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] s390/delay: Fix comment typo
Message-ID: <YtfJgyVQzgkzSouS@osiris>
References: <20220715043610.17229-1-wangborong@cdjrlc.com>
 <Ytb2V3ay5qMY3yt+@li-4a3a4a4c-28e5-11b2-a85c-a8d192c6f089.ibm.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <Ytb2V3ay5qMY3yt+@li-4a3a4a4c-28e5-11b2-a85c-a8d192c6f089.ibm.com>
Precedence: bulk

On Tue, Jul 19, 2022 at 08:22:15PM +0200, Alexander Gordeev wrote:
> On Fri, Jul 15, 2022 at 12:36:10PM +0800, Jason Wang wrote:
> > The double `that' is duplicated in line 19, remove one.
> > 
> > Signed-off-by: Jason Wang <wangborong@cdjrlc.com>
> > ---
> >  arch/s390/lib/delay.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/arch/s390/lib/delay.c b/arch/s390/lib/delay.c
> > index f7f5adea8940..c32bc8f7c1fd 100644
> > --- a/arch/s390/lib/delay.c
> > +++ b/arch/s390/lib/delay.c
> > @@ -16,7 +16,7 @@ void __delay(unsigned long loops)
> >          /*
> >           * To end the bloody studid and useless discussion about the
> >           * BogoMips number I took the liberty to define the __delay
> > -         * function in a way that that resulting BogoMips number will
> > +         * function in a way that resulting BogoMips number will
> >           * yield the megahertz number of the cpu. The important function
> >           * is udelay and that is done using the tod clock. -- martin.
> >           */
> 
> Applied, thanks!

Ahem :) That should have been actually "fixed" to "that the", instead
of removing the double "that". And by the way, just two lines above is
another obvious typo...

But seriously, the whole comment is entirely outdated and simply
wrong.  We don't use __delay() to calculate the BogoMips number, nor
does the function return a value that correlates with the megahertz
number of the cpu nowadays. It just loops a random time (where the cpu
is free to detect the pointless loop and optimize it away anyway).

So the right thing to do would be to remove the complete comment, and
maybe add a new comment - but please don't apply this patch.