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From: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
To: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>,
	linux-ide <linux-ide@vger.kernel.org>,
	Borislav Petkov <petkovbb@googlemail.com>
Subject: Re: [PATCH] ide: endian annotations in ide-floppy.c
Date: Thu, 19 Jun 2008 21:49:05 +0200	[thread overview]
Message-ID: <200806192149.06139.bzolnier@gmail.com> (raw)
In-Reply-To: <1213833689.2125.31.camel@brick>

On Thursday 19 June 2008, Harvey Harrison wrote:
> On Thu, 2008-06-19 at 00:34 +0100, Al Viro wrote:
> > On Wed, Jun 18, 2008 at 03:57:35PM -0700, Harvey Harrison wrote:
> > > Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
> > > ---
> > >  drivers/ide/ide-floppy.c |   16 ++++++++--------
> > >  1 files changed, 8 insertions(+), 8 deletions(-)
> > > 
> > > diff --git a/drivers/ide/ide-floppy.c b/drivers/ide/ide-floppy.c
> > > index f05fbc2..cba39fa 100644
> > > --- a/drivers/ide/ide-floppy.c
> > > +++ b/drivers/ide/ide-floppy.c
> > > @@ -921,10 +921,10 @@ static int ide_floppy_get_flexible_disk_page(ide_drive_t *drive)
> > >  	set_disk_ro(floppy->disk, floppy->wp);
> > >  	page = &pc.buf[8];
> > >  
> > > -	transfer_rate = be16_to_cpu(*(u16 *)&pc.buf[8 + 2]);
> > > -	sector_size   = be16_to_cpu(*(u16 *)&pc.buf[8 + 6]);
> > > -	cyls          = be16_to_cpu(*(u16 *)&pc.buf[8 + 8]);
> > > -	rpm           = be16_to_cpu(*(u16 *)&pc.buf[8 + 28]);
> > > +	transfer_rate = be16_to_cpup((__be16 *)&pc.buf[8 + 2]);
> > > +	sector_size   = be16_to_cpup((__be16 *)&pc.buf[8 + 6]);
> > > +	cyls          = be16_to_cpup((__be16 *)&pc.buf[8 + 8]);
> > > +	rpm           = be16_to_cpup((__be16 *)&pc.buf[8 + 28]);
> > 
> > Pointless, IMO - just s/u16/__be16/ in the above.
> 
> The (admittedly) small reason I did it this way is that some arches do
> have a more efficient pointer version.  Not that they use this code, but
> in principle that's why I used the pointer version.

this indeed seems to result in (tiny) improvement on x86-32:

   text    data     bss     dec     hex filename
   7377     196       0    7573    1d95 drivers/ide/ide-floppy.o.before
   7370     196       0    7566    1d8e drivers/ide/ide-floppy.o.after

thus I applied it as it is

      reply	other threads:[~2008-06-19 20:46 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-06-18 22:57 [PATCH] ide: endian annotations in ide-floppy.c Harvey Harrison
2008-06-18 23:34 ` Al Viro
2008-06-19  0:01   ` Harvey Harrison
2008-06-19 19:49     ` Bartlomiej Zolnierkiewicz [this message]

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