RE: [PATCH] net/i40e: avx512 fast-free path bug fix

["Zhang, Qi Z" <qi.z.zhang@intel.com>]

> -----Original Message-----
> From: Morten Brørup <mb@smartsharesystems.com>
> Sent: Wednesday, March 8, 2023 4:26 AM
> To: Kamalakshitha Aligeri <kamalakshitha.aligeri@arm.com>; Zhang, Yuying
> <yuying.zhang@intel.com>; Xing, Beilei <beilei.xing@intel.com>; Rong, Leyi
> <leyi.rong@intel.com>; ruifeng.wang@arm.com; feifei.wang2@arm.com
> Cc: nd@arm.com; dev@dpdk.org
> Subject: RE: [PATCH] net/i40e: avx512 fast-free path bug fix
> 
> > From: Kamalakshitha Aligeri [mailto:kamalakshitha.aligeri@arm.com]
> > Sent: Tuesday, 7 March 2023 20.32
> >
> > In i40e_tx_free_bufs_avx512 fast-free path, when cache is NULL, non
> > fast-free path is being executed. Fixed the bug by calling
> > rte_mempool_generic_put API that handles the cache==NULL case.
> >
> > Fixes: 5171b4ee6b6b ("net/i40e: optimize Tx by using AVX512")
> > Cc: leyi.rong@intel.com
> > Cc: stable@dpdk.org
> >
> > Signed-off-by: Kamalakshitha Aligeri <kamalakshitha.aligeri@arm.com>
> > Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>
> > Reviewed-by: Feifei Wang <feifei.wang2@arm.com>
> > ---
> >  .mailmap                                |  1 +
> >  drivers/net/i40e/i40e_rxtx_vec_avx512.c | 12 ++++--------
> >  2 files changed, 5 insertions(+), 8 deletions(-)
> >
> > diff --git a/.mailmap b/.mailmap
> > index a9f4f28fba..2581d0efe7 100644
> > --- a/.mailmap
> > +++ b/.mailmap
> > @@ -677,6 +677,7 @@ Kai Ji <kai.ji@intel.com>  Kaiwen Deng
> > <kaiwenx.deng@intel.com>  Kalesh AP
> > <kalesh-anakkur.purayil@broadcom.com>
> >  Kamalakannan R <kamalakannan.r@intel.com>
> > +Kamalakshitha Aligeri <kamalakshitha.aligeri@arm.com>
> >  Kamil Bednarczyk <kamil.bednarczyk@intel.com>  Kamil Chalupnik
> > <kamilx.chalupnik@intel.com>  Kamil Rytarowski
> > <kamil.rytarowski@caviumnetworks.com>
> > diff --git a/drivers/net/i40e/i40e_rxtx_vec_avx512.c
> > b/drivers/net/i40e/i40e_rxtx_vec_avx512.c
> > index d3c7bfd121..ad0893324d 100644
> > --- a/drivers/net/i40e/i40e_rxtx_vec_avx512.c
> > +++ b/drivers/net/i40e/i40e_rxtx_vec_avx512.c
> > @@ -783,16 +783,13 @@ i40e_tx_free_bufs_avx512(struct i40e_tx_queue
> > *txq)
> >  		struct rte_mempool_cache *cache =
> > rte_mempool_default_cache(mp,
> >  				rte_lcore_id());
> >
> > -		if (!cache || cache->len == 0)
> > -			goto normal;
> > -
> > -		cache_objs = &cache->objs[cache->len];
> > -
> > -		if (n > RTE_MEMPOOL_CACHE_MAX_SIZE) {
> > -			rte_mempool_ops_enqueue_bulk(mp, (void *)txep,
> n);
> > +		if (!cache || n > RTE_MEMPOOL_CACHE_MAX_SIZE) {
> > +			rte_mempool_generic_put(mp, (void *)txep, n,
> cache);
> >  			goto done;
> >  		}
> >
> > +		cache_objs = &cache->objs[cache->len];
> > +
> >  		/* The cache follows the following algorithm
> >  		 *   1. Add the objects to the cache
> >  		 *   2. Anything greater than the cache min value (if it
> > @@ -824,7 +821,6 @@ i40e_tx_free_bufs_avx512(struct i40e_tx_queue
> *txq)
> >  		goto done;
> >  	}
> >
> > -normal:
> >  	m = rte_pktmbuf_prefree_seg(txep[0].mbuf);
> >  	if (likely(m)) {
> >  		free[0] = m;
> > --
> > 2.25.1
> >
> 
> An improvement of the copy-paste code we are aiming to replace by proper
> use of the mempool API.
> 
> But still an improvement.
> 
> Acked-by: Morten Brørup <mb@smartsharesystems.com>

Applied to dpdk-next-net-intel.

Thanks
Qi