[PATCH] rcu: remove VLAs

[David Marchand]

Andre,

On Fri, Mar 7, 2025 at 2:40 AM Andre Muezerie
<andremue at linux.microsoft.com> wrote:
>
> There are two lines that were using VLAs, which are not supported by
> MSVC.
>
> 1)
> ../lib/rcu/rte_rcu_qsbr.c:326:12: warning: variable length array used [-Wvla]
>   326 |         char data[dq->esize];
>       |                   ^~~~~~~~~
> 2)
> ../lib/rcu/rte_rcu_qsbr.c:389:12: warning: variable length array used [-Wvla]
>   389 |         char data[dq->esize];
>       |                   ^~~~~~~~~
>
> The short-term fix is to use alloca, to allow progress with the msvc
> compatibility work.
> The long-term plan involves API changes and therefore can only be applied
> with a new release. This long-term plan consists of introducing some
> reasonable limitation on RCU DQ element size.
>
> Signed-off-by: Andre Muezerie <andremue at linux.microsoft.com>

Afaiu, enabling RCU with MSVC depends on this current patch and a fix
in test/ipfrag:
https://patchwork.dpdk.org/project/dpdk/patch/1741313581-14300-1-git-send-email-andremue@linux.microsoft.com/.
Is there anything else missing?

If not, then I would be for doing this enabling as part of this
current patch (I can do this when applying).
WDYT?


-- 
David Marchand