03/04/2019 21:21, Eads, Gage:
> > 03/04/2019 19:34, Gage Eads:
> > > This operation can be used for non-blocking algorithms, such as a
> > > non-blocking stack or ring.
> > >
> > > Signed-off-by: Gage Eads <gage.e...@intel.com>
> > > Reviewed-by: Honnappa Nagarahalli <honnappa.nagaraha...@arm.com>
> > > ---
> > > --- a/lib/librte_eal/common/include/arch/x86/rte_atomic_64.h
> > > +++ b/lib/librte_eal/common/include/arch/x86/rte_atomic_64.h
> > > +/**
> > > + * An atomic compare and set function used by the mutex functions.
> > > + * (Atomically) Equivalent to:
> > > + * if (*dst == *exp)
> > > + * *dst = *src
> > > + * else
> > > + * *exp = *dst
> > > + *
> > > + * @note The success and failure arguments must be one of the
> > > +__ATOMIC_* values
> > > + * defined in the C++11 standard. For details on their behavior,
> > > +refer to the
> > > + * standard.
> > > + *
> > > + * @param dst
> > > + * The destination into which the value will be written.
> > > + * @param exp
> > > + * Pointer to the expected value. If the operation fails, this memory
> > > is
> > > + * updated with the actual value.
> > > + * @param src
> > > + * Pointer to the new value.
> > > + * @param weak
> > > + * A value of true allows the comparison to spuriously fail and allows
> > > the
> > > + * 'exp' update to occur non-atomically (i.e. a torn read may occur).
> > > + * Implementations may ignore this argument and only implement the
> > strong
> > > + * variant.
> > > + * @param success
> > > + * If successful, the operation's memory behavior conforms to this (or
> > > a
> > > + * stronger) model.
> > > + * @param failure
> > > + * If unsuccessful, the operation's memory behavior conforms to this
> > > (or
> > a
> > > + * stronger) model. This argument cannot be __ATOMIC_RELEASE,
> > > + * __ATOMIC_ACQ_REL, or a stronger model than success.
> > > + * @return
> > > + * Non-zero on success; 0 on failure.
> > > + */
> > > +static inline int __rte_experimental
> > > +rte_atomic128_cmp_exchange(rte_int128_t *dst,
> > > + rte_int128_t *exp,
> > > + const rte_int128_t *src,
> > > + unsigned int weak,
> > > + int success,
> > > + int failure)
> >
> > I was thinking about keeping the doxygen in the generic file.
> > Is it possible?
> >
>
> We'd need to include the definition of rte_int128_t, so we'd also need either
> an ifdef on RTE_ARCH_64 or RTE_ARCH_X86_64 to protect 32-bit builds. That
> macro would prevent doxygen from parsing that section, unless we add a
> workaround like, for example:
>
> #if defined(RTE_ARCH_64) || defined(__DOXYGEN__)
>
> So the patch would look like the v3, with the declaration in
> generic/rte_atomic.h, but with that preprocessor change. If we change
> RTE_ARCH_X86_64 to RTE_ARCH_64, I'd add a note clarifying that it's only
> implemented for x86-64. What do you think?
I would like to see the doc in the generic file
and the implementation in the x86 file.
I tried forward declaration of the typedef:
struct rte_int128;
typedef struct rte_int128 rte_int128_t;
I don't why it does not work.
So I'm trying to protect the declaration with
#ifdef __DOXYGEN__
