[dpdk-dev] [PATCH v7 02/10] eal: add power management intrinsics

[Thomas Monjalon]

20/10/2020 04:49, Ruifeng Wang:
> From: Thomas Monjalon <thomas at monjalon.net>
> > 15/10/2020 14:04, Anatoly Burakov:
> > > +/**
> > > + * This function is not supported on ARM.
> > > + */
> > > +static inline void
> > > +rte_power_monitor(const volatile void *p, const uint64_t
> > expected_value,
> > > +               const uint64_t value_mask, const uint64_t tsc_timestamp,
> > > +               const uint8_t data_sz) {
> > > +       RTE_SET_USED(p);
> > > +       RTE_SET_USED(expected_value);
> > > +       RTE_SET_USED(value_mask);
> > > +       RTE_SET_USED(tsc_timestamp);
> > > +       RTE_SET_USED(data_sz);
> > > +}
> > 
> > Are you sure it cannot be partially supported with WFE instruction?
> > 
> Armv8 WFE instruction can support monitoring of specific address for changes, 
> but not monitoring of TSC timestamp. 

So it is a partial support.

We must try hard to unify architectures support
to avoid #ifdef everywhere.

I don't agree with how are managed new instructions recently.
Please look further.