RE: [PATCH v3] kni: optimize alloc queue release

["Naga Harish K, S V" <s.v.naga.harish.k@intel.com>]

Hi Jay,

> -----Original Message-----
> From: Jayatheerthan, Jay <jay.jayatheerthan@intel.com>
> Sent: Thursday, April 14, 2022 8:51 PM
> To: Naga Harish K, S V <s.v.naga.harish.k@intel.com>;
> ferruh.yigit@xilinx.com; Yigit, Ferruh <ferruh.yigit@intel.com>
> Cc: dev@dpdk.org
> Subject: RE: [PATCH v3] kni: optimize alloc queue release
> 
> > -----Original Message-----
> > From: Naga Harish K, S V <s.v.naga.harish.k@intel.com>
> > Sent: Wednesday, April 13, 2022 8:27 PM
> > To: ferruh.yigit@xilinx.com; Yigit, Ferruh <ferruh.yigit@intel.com>
> > Cc: Jayatheerthan, Jay <jay.jayatheerthan@intel.com>; dev@dpdk.org
> > Subject: [PATCH v3] kni: optimize alloc queue release
> >
> > the kni alloc queue is filled with physical addresses of mbufs
> 
> nitpick: "The" instead of "the".

 Updated in v4 patch.

> 
> > for kernel consumption. Any unused mbufs in the alloc queue are freed
> > during shutdown sequence in rte_kni_release.
> >
> > In the current existing implementation, for freeing one entry of
> 
> nitpick: current and existing are redundant. Can keep one.

Updated in v4 patch.

> 
> > alloc queue all the objects of the mempool are traversed. This process
> > is repeated for all the objects of the alloc queue which consumes lot
> > of cpu cycles.
> >
> > Instead of using mempool object iteration method,use
> > ``rte_mem_iova2virt()`` api to get the virtual address for the
> > physical addresses of alloc_q objects.
> > This speeds up the freeing process.
> >
> > Signed-off-by: Naga Harish K S V <s.v.naga.harish.k@intel.com>
> > ---
> > v2:
> > * fix checkpatch errors
> >
> > v3:
> > * fix commit message as per review comments
> > ---
> >  lib/kni/rte_kni.c | 23 ++++++++---------------
> >  1 file changed, 8 insertions(+), 15 deletions(-)
> >
> > diff --git a/lib/kni/rte_kni.c b/lib/kni/rte_kni.c index
> > 7971c56bb4..f443e5b2fc 100644
> > --- a/lib/kni/rte_kni.c
> > +++ b/lib/kni/rte_kni.c
> > @@ -375,26 +375,19 @@ va2pa_all(struct rte_mbuf *mbuf)  }
> >
> >  static void
> > -obj_free(struct rte_mempool *mp __rte_unused, void *opaque, void
> *obj,
> > -		unsigned obj_idx __rte_unused)
> > -{
> > -	struct rte_mbuf *m = obj;
> > -	void *mbuf_phys = opaque;
> > -
> > -	if (va2pa(m) == mbuf_phys)
> > -		rte_pktmbuf_free(m);
> > -}
> > -
> > -static void
> > -kni_free_fifo_phy(struct rte_mempool *mp, struct rte_kni_fifo *fifo)
> > +kni_free_fifo_phy(struct rte_kni_fifo *fifo)
> >  {
> >  	void *mbuf_phys;
> >  	int ret;
> > +	struct rte_mbuf *m;
> >
> >  	do {
> >  		ret = kni_fifo_get(fifo, &mbuf_phys, 1);
> > -		if (ret)
> > -			rte_mempool_obj_iter(mp, obj_free, mbuf_phys);
> > +		if (ret) {
> > +			m = (struct rte_mbuf *)
> > +				rte_mem_iova2virt((rte_iova_t)mbuf_phys);
> > +			rte_pktmbuf_free(m);
> > +		}
> >  	} while (ret);
> >  }
> >
> > @@ -440,7 +433,7 @@ rte_kni_release(struct rte_kni *kni)
> >  	if (kni_fifo_count(kni->rx_q))
> >  		RTE_LOG(ERR, KNI, "Fail to free all Rx-q items\n");
> >
> > -	kni_free_fifo_phy(kni->pktmbuf_pool, kni->alloc_q);
> > +	kni_free_fifo_phy(kni->alloc_q);
> >  	kni_free_fifo(kni->tx_q);
> >  	kni_free_fifo(kni->free_q);
> >
> > --
> > 2.23.0