Re: [dpdk-dev] [PATCH v2 0/2] Use WFE for spinlock and ring

[Ruifeng Wang <Ruifeng.Wang@arm.com>]

> -----Original Message-----
> From: David Marchand <david.marchand@redhat.com>
> Sent: Thursday, March 25, 2021 10:58 PM
> To: Honnappa Nagarahalli <Honnappa.Nagarahalli@arm.com>
> Cc: dev <dev@dpdk.org>; nd <nd@arm.com>; thomas@monjalon.net;
> jerinj@marvell.com; Ruifeng Wang <Ruifeng.Wang@arm.com>; Phil Yang
> <Phil.Yang@arm.com>; Joyce Kong <Joyce.Kong@arm.com>; Ananyev,
> Konstantin <konstantin.ananyev@intel.com>
> Subject: Re: [dpdk-dev] [PATCH v2 0/2] Use WFE for spinlock and ring
> 
> Hello,
> 
> On Fri, Sep 25, 2020 at 4:30 PM David Marchand
> <david.marchand@redhat.com> wrote:
> >
> > Hello Honnappa,
> >
> > On Sun, May 3, 2020 at 11:32 PM Honnappa Nagarahalli
> > <Honnappa.Nagarahalli@arm.com> wrote:
> > >
> > > <snip>
> > >
> > > > Subject: Re: [PATCH v2 0/2] Use WFE for spinlock and ring
> > > >
> > > > On Sun, Apr 26, 2020 at 10:39 AM Gavin Hu <gavin.hu@arm.com> wrote:
> > > > >
> > > > > The rte_wait_until_equal_xxx APIs abstract the functionality of
> > > > > 'polling for a memory location to become equal to a given value'[1].
> > > > >
> > > > > Use the API for the rte spinlock and ring implementations.
> > > > >
> > > > > [1] http://patches.dpdk.org/cover/62703/
> > > > >
> > > > > Gavin Hu (2):
> > > > >   spinlock: use wfe to reduce contention on aarch64
> > > > >   ring: use wfe to wait for ring tail update on aarch64
> > > >
> > > > This would result in rte_ring and rte_spinlock APIs becoming
> > > > experimental and this breaks compilation for external applications
> > > > using stable ring and spinlock APIs.
> > > > IIRC, it was the reason why these patches were dropped with the
> > > > introduction of the rte_wait_until_equal_* API.
> > > Agreed, the rte_ring new sync modes are resulting in different use cases
> for these APIs. We need to take a relook at the APIs.
> >
> > Will we reconsider this series now that the wait until equal is going stable?
> 
> Any update?
> I suppose this would need some rebasing after the ring library changes.

Sorry for the late response.
This series has been rebased and v3 posted.
I have problem to mark v2 as superseded.

Thank you.
> 
> Thanks.
> 
> 
> --
> David Marchand