Re: [Xen-devel] [PATCH 02/16] x86: fix: make atomic_read() param const

[Corneliu ZUZU <czuzu@xxxxxxxxxxxxxxx>]

On 7/12/2016 1:22 PM, Andrew Cooper wrote:
> On 12/07/16 11:11, Corneliu ZUZU wrote:
> > > > > If you are really feeling up to it, having a common xen/atomic.h with
> > > > >
> > > > > typedef struct { int counter; } atomic_t;
> > > > > #define ATOMIC_INIT(i) { (i) }
> > > > >
> > > > > and some prototypes such as:
> > > > >
> > > > > static inline int atomic_read(const atomic_t *v);
> > > > >
> > > > > would be great, but this looks like it has the possibility to turn
> > > > > into
> > > > > a rats nest.  If it does, then just doubling up this code for arm
> > > > > is ok.
> > > > >
> > > > > ~Andrew
> > > > Yes, that might be more complicated than we expect and I don't know if
> > > > making code such as this common would be a good idea, usually these
> > > > functions are always architecture-specific.
> > > I only suggested making the prototype common, not the implementation.
> > > As such, the issue you accidentally introduced would become a hard build
> > > failure on affected architectures, rather than a subtle build failure in
> > > common code at some point in the future.
> > >
> > > ~Andrew
> > Oh, I see, good idea, I've just tested it and it works, what did you
> > have in mind when you said it could cause problems?
> The build issues would come at some point later when someone attempts to
> atomic_read() a constant atomic_t in common code, when the ARM build
> would break.
>
> ~Andrew
Ooh, no, I was asking what you meant when you said "this looks like it 
has the possibility to turn into a rats nest" in your first message, not 
the thing about hard build failure..
Zuzu C.


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
https://lists.xen.org/xen-devel