Re: [PATCH v3 10/27] net/i40e: avoid rte malloc in RSS RETA operations

Bruce Richardson
2026-02-17T12:46:55Z

On Tue, Feb 17, 2026 at 01:32:05PM +0100, Burakov, Anatoly wrote:
> On 2/16/2026 6:06 PM, Bruce Richardson wrote:
> > On Wed, Feb 11, 2026 at 01:52:52PM +0000, Anatoly Burakov wrote:
> > > Currently, when updating or querying RSS redirection table (RETA), we
> > > are using rte_zmalloc followed by an immediate rte_free. This is not
> > > needed as this memory is not being stored anywhere, so replace it with
> > > regular malloc/free.
> > >
> > > Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
> > > ---
> > > drivers/net/intel/i40e/i40e_ethdev.c | 8 ++++----
> > > 1 file changed, 4 insertions(+), 4 deletions(-)
> > >
> > > diff --git a/drivers/net/intel/i40e/i40e_ethdev.c b/drivers/net/intel/i40e/i40e_ethdev.c
> > > index 06430e6319..654b0e5d16 100644
> > > --- a/drivers/net/intel/i40e/i40e_ethdev.c
> > > +++ b/drivers/net/intel/i40e/i40e_ethdev.c
> > > @@ -4630,7 +4630,7 @@ i40e_dev_rss_reta_update(struct rte_eth_dev *dev,
> > > return -EINVAL;
> > > }
> > > - lut = rte_zmalloc("i40e_rss_lut", reta_size, 0);
> > > + lut = calloc(1, reta_size);
> > > if (!lut) {
> > > PMD_DRV_LOG(ERR, "No memory can be allocated");
> > > return -ENOMEM;
> > > @@ -4649,7 +4649,7 @@ i40e_dev_rss_reta_update(struct rte_eth_dev *dev,
> > > pf->adapter->rss_reta_updated = 1;
> > > out:
> > > - rte_free(lut);
> > > + free(lut);
> > > return ret;
> > > }
> >
> > For i40e do we not have a reasonable max reta size that we could use for a
> > local array variable, save allocating and freeing entirely?
> >
>
> It's on the order of kilobytes I think so I decided against stack allocation
> for this scenario.
>
If it's only a kilobyte, I would tend to go with stack allocation.
However, it's up to you.

/Bruce