RE: Question on atomic_inc/dec

RE: Question on atomic_inc/dec

[Perez-Gonzalez, Inaky]

> From: sankar [mailto:san_madhav@hotmail.com]

>  any solution to the original problem???
> (atomic_inc() defintion not there in redhat 9.0 asm/atomic.h)

Create an atomic.h header file in your source tree with the code
below, but bear in mind that porting to other arches might be painful:

struct atomic
{
  volatile int i;
}

  /* Simple atomic increment. */

static inline
void atomic_inc (struct atomic *a)
{
    asm volatile (
      "lock; incl %0"
      : "=m" (a->i)
      : "m" (a->i));
}

  /* Simple atomic decrement. */

static inline
void atomic_dec (struct atomic *a)
{
    asm volatile (
      "lock; decl %0"
      : "=m" (a->i)
      : "m" (a->i));
}

Iñaky Pérez-González -- Not speaking for Intel -- all opinions are my own (and my fault)

Re: [OT] Question on atomic_inc/dec

[Petr Vandrovec]

On Wed, Oct 15, 2003 at 10:38:14AM -0700, Perez-Gonzalez, Inaky wrote:
> > From: sankar [mailto:san_madhav@hotmail.com]
> 
> >  any solution to the original problem???
> > (atomic_inc() defintion not there in redhat 9.0 asm/atomic.h)
> 
> Create an atomic.h header file in your source tree with the code
> below, but bear in mind that porting to other arches might be painful:

It is OT, but if you are interested, take a look at include/private/*atomic*,
include/private/*/*atomic* and relevant portions (ncphost) of configure.ac 
in the ncpfs package (http://platan.vc.cvut.cz/ftp/pub/linux/ncpfs/ncpfs-2.2.3.tar.gz).

It contains UP, pthread based, and several asm optimized versions of
atomic ops. I'm not 100% sure that all asm versions work correctly,
but I have received no complaints yet...
					Best regards,
						Petr Vandrovec
						vandrove@vc.cvut.cz