[dpdk-dev] [PATCH 3/4] eal: allow checking CPU flags by name

David Marchand david.marchand at redhat.com
Fri Jun 28 15:34:10 CEST 2019

On Fri, Jun 28, 2019 at 2:40 PM Bruce Richardson <bruce.richardson at intel.com>

> On Thu, Jun 27, 2019 at 03:22:14PM +0200, David Marchand wrote:
> >    On Wed, May 29, 2019 at 5:42 PM Bruce Richardson
> >    <[1]bruce.richardson at intel.com> wrote:
> >
> >      Rather than using enum values for CPU flags, which means the symbols
> >      don't
> >      exist on other architectures, provide a flag lookup by name,
> >      allowing us to
> >      unconditionally check for a CPU flag.
> >
> >    Did you consider passing a string for the CPU architecture rather than
> >    an enum?
> >    It would have to be compared to RTE_ARCH in
> >    rte_cpu_get_flagname_enabled.
> >    Or to accomodate with x86_64/i686, this could be a cpu arch family.
> >    This avoids adding a new C type that seems quite limited wrt its uses.
> >    --
> >    David Marchand
> >
> I'm not sure I really see the value in having string names for the
> architecture values, I think it would be a lot more clunky to manage rather
> than having an enum value. The key difference vs the flags is that the
> flags are only valid per-architecture while the architecture defines can be
> globally valid, and secondly there is a finite, and small, number of
> architectures compared to the number of flags supported.
> If you feel strongly about it I can investigate it, but I'm not sure I see
> the value in doing so right now if the only benefit is avoiding the enum.

I suppose we won't have too much trouble handling ABI breakage (thinking
about when we will remove x86 support).
Ok, let's go with this.

David Marchand

More information about the dev mailing list