On 04.04.2017 23:52, Ola Liljedahl wrote: > Sending from my ARM email account, I hope Outlook does not mess up the > format. > > > > On 04/04/2017, 22:21, "Dmitry Eremin-Solenikov" > <dmitry.ereminsoleni...@linaro.org> wrote: > >> On 04.04.2017 21:48, Brian Brooks wrote: >>> Signed-off-by: Ola Liljedahl <ola.liljed...@arm.com> >>> Reviewed-by: Brian Brooks <brian.bro...@arm.com> >>> Reviewed-by: Honnappa Nagarahalli <honnappa.nagaraha...@arm.com> >> >>> >>> +/*********************************************************************** >>> ******* >>> + * bitset abstract data type >>> + >>> ************************************************************************* >>> ****/ >>> +/* This could be a struct of scalars to support larger bit sets */ >>> + >>> +#if ATOM_BITSET_SIZE <= 32 >> >> Maybe I missed, where did you set this macro? > In odp_config_internal.h > It is a build time configuration. > >> >> Also, why do you need several versions of bitset? Can you stick to one >> size that fits all? > Some 32-bit archs (ARMv7a, x86) will only support 64-bit atomics (AFAIK). > Only x86-64 and ARMv8a supports 128-bit atomics (and compiler support for > 128-bit atomics for ARMv8a is a bit lackingŠ). > Other architectures might only support 32-bit atomic operations.
What will be the major outcome of settling on the 64-bit atomics? > I think the user should have control over this but if you think that we > should just select the max value that is supported by the architecture in > question and thus skip one build configuration, I am open to this. We will > still need separate versions for 32/64/128 bits because there are slight > differences in the syntax and implementation. Such are the vagaries of the > C standard (and GCC extensions). > > >> Any real reason for the following defines? Why do you need them? > The functions were added as they were needed, e.g. in > odp_schedule_scalable.c. > I dont think there is anyone which is not used anymore but can > double-check that. Well. I maybe should rephrase my question: why do you think that it's better to have bitset_andn(a, b), rather than just a &~b ? -- With best wishes Dmitry
