Re: [PATCH 01/10] ide: add flags query macros

[Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>]

On Sunday 15 February 2009, Sam Ravnborg wrote:
> On Sun, Feb 15, 2009 at 07:01:41PM +0100, Borislav Petkov wrote:
> > Hi,
> > 
> > > > Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
> > > > ---
> > > >  include/linux/ide.h |  166 +++++++++++++++++++++++++++++++++++++++++++++++++++
> > > >  1 files changed, 166 insertions(+), 0 deletions(-)
> > > > 
> > > > diff --git a/include/linux/ide.h b/include/linux/ide.h
> > > > index c75631c..f133062 100644
> > > > --- a/include/linux/ide.h
> > > > +++ b/include/linux/ide.h
> > > > @@ -497,6 +497,82 @@ enum {
> > > >  	IDE_AFLAG_NO_AUTOCLOSE		= (1 << 24),
> > > >  };
> > > >  
> > > > +#define ide_drv_drq_int(drive) \
> > > > +	((drive)->atapi_flags & IDE_AFLAG_DRQ_INTERRUPT)
> > > 
> > > Why not use a static inline here so we get proper typecheck.
> > > And then convert the return result to a bool (0/1) so you
> > > do not have to do this at the call site.
> > > 
> > > I counted at least three places in ide-cd that does a local
> > > transformation to a bool and I saw nowhere the actual bit value
> > > was used.
> > 
> > I'm assuming you're talking about those places (and similar):
> > 
> > drive->dma = !!(drive->dev_flags & IDE_DFLAG_USING_DMA);
> 
> And in other places we do:
> 
> ide_drv_drq_int(drive) ? 1 : 0
> 
> > Well, actually we almost never use the 0/1 bool value and this one
> > case is more of an exception. If you take a closer look, we don't have
> > setters/getters ...,
> I scanned all your patches and I did not find a single place where
> the macros was not used as a bool value.
> Mostly in if (ide_drv_drq_int(drive)) .. and ide_drv_drq_int(drive) &&
> statements.
> 
> > So the macros as such are
> > simply to save some stack and improve readability and since the whole
> > thing keeps changing we might just as well turn them into static inlines
> > one fine day :).
> 
> gcc will optmize the static inline functions so there is no drawbacks only
> better type checking.

Lets do it "today" then. :)

Thanks,
Bart