[dpdk-dev] [PATCH v8 3/5] kni: add app specific mempool create & free routine

[Vamsi Krishna Attunuru]

> -----Original Message-----
> From: Andrew Rybchenko <arybchenko at solarflare.com>
> Sent: Tuesday, July 23, 2019 4:20 PM
> To: Vamsi Krishna Attunuru <vattunuru at marvell.com>; dev at dpdk.org
> Cc: thomas at monjalon.net; Jerin Jacob Kollanukkaran <jerinj at marvell.com>;
> olivier.matz at 6wind.com; ferruh.yigit at intel.com; anatoly.burakov at intel.com;
> Kiran Kumar Kokkilagadda <kirankumark at marvell.com>
> Subject: Re: [dpdk-dev] [PATCH v8 3/5] kni: add app specific mempool create &
> free routine
> 
> On 7/23/19 8:38 AM, vattunuru at marvell.com wrote:
> > From: Vamsi Attunuru <vattunuru at marvell.com>
> >
> > When KNI operates in IOVA = VA mode, it requires mbuf memory to be
> > physically contiguous to ensure KNI kernel module could translate IOVA
> > addresses properly. Patch adds a KNI specific mempool create routine
> > to populate the KNI packet mbuf pool with memory objects that are
> > being on a page.
> >
> > KNI applications need to use this mempool create & free routines so
> > that mbuf related requirements in IOVA = VA mode are handled inside
> > those routines based on the enabled mode.
> >
> > Updated the release notes with these new routine details.
> >
> > Signed-off-by: Vamsi Attunuru <vattunuru at marvell.com>
> > Signed-off-by: Kiran Kumar K <kirankumark at marvell.com>
> > ---
> >   doc/guides/rel_notes/release_19_08.rst |  6 ++++
> >   examples/kni/main.c                    |  6 +++-
> >   lib/librte_kni/Makefile                |  1 +
> >   lib/librte_kni/meson.build             |  1 +
> >   lib/librte_kni/rte_kni.c               | 59 ++++++++++++++++++++++++++++++++++
> >   lib/librte_kni/rte_kni.h               | 49 ++++++++++++++++++++++++++++
> >   lib/librte_kni/rte_kni_version.map     |  2 ++
> >   7 files changed, 123 insertions(+), 1 deletion(-)
> >
> > diff --git a/doc/guides/rel_notes/release_19_08.rst
> > b/doc/guides/rel_notes/release_19_08.rst
> > index 0a3f840..bd01e99 100644
> > --- a/doc/guides/rel_notes/release_19_08.rst
> > +++ b/doc/guides/rel_notes/release_19_08.rst
> > @@ -281,6 +281,12 @@ API Changes
> >     offload flag from the library. The application must set this flag if it is
> >     supported by the platform and application wishes to use it.
> >
> > +* kni: ``rte_kni_pktmbuf_pool_create`` ``rte_kni_pktmbuf_pool_free``
> > +functions
> > +  were introduced for KNI applications for creating & freeing packet pool.
> > +  Since IOVA=VA mode was added in KNI, packet pool's mbuf memory
> > +should be
> > +  physically contiguous for the KNI kernel module to work in IOVA=VA
> > +mode,
> > +  this requirment was taken care in the kni packet pool creation fucntions.
> > +
> >
> >   ABI Changes
> >   -----------
> > diff --git a/examples/kni/main.c b/examples/kni/main.c index
> > 4710d71..3b9c067 100644
> > --- a/examples/kni/main.c
> > +++ b/examples/kni/main.c
> > @@ -975,7 +975,7 @@ main(int argc, char** argv)
> >   		rte_exit(EXIT_FAILURE, "Could not parse input parameters\n");
> >
> >   	/* Create the mbuf pool */
> > -	pktmbuf_pool = rte_pktmbuf_pool_create("mbuf_pool", NB_MBUF,
> > +	pktmbuf_pool = rte_kni_pktmbuf_pool_create("mbuf_pool", NB_MBUF,
> >   		MEMPOOL_CACHE_SZ, 0, MBUF_DATA_SZ, rte_socket_id());
> >   	if (pktmbuf_pool == NULL) {
> >   		rte_exit(EXIT_FAILURE, "Could not initialise mbuf pool\n"); @@
> > -1043,6 +1043,10 @@ main(int argc, char** argv)
> >   			continue;
> >   		kni_free_kni(port);
> >   	}
> > +
> > +	if (pktmbuf_pool)
> 
> Typically pointer is compared to NULL, but it is not required here anyway, since
> rte_mempool_free() handles NULL perfectly itself.

Ack

> 
> > +		rte_kni_pktmbuf_pool_free(pktmbuf_pool);
> > +
> >   	for (i = 0; i < RTE_MAX_ETHPORTS; i++)
> >   		if (kni_port_params_array[i]) {
> >   			rte_free(kni_port_params_array[i]);
> 
> <...>
> 
> > diff --git a/lib/librte_kni/rte_kni.h b/lib/librte_kni/rte_kni.h index
> > 5699a64..7f11927 100644
> > --- a/lib/librte_kni/rte_kni.h
> > +++ b/lib/librte_kni/rte_kni.h
> > @@ -20,6 +20,7 @@
> >   #include <rte_pci.h>
> >   #include <rte_memory.h>
> >   #include <rte_mempool.h>
> > +#include <rte_mbuf_pool_ops.h>
> 
> I don't understand why it is included here.
> 
included to fix compilation of rte_kni.c post this patch changes,  could be included in rte_kni.c though.

> >   #include <rte_ether.h>
> >
> >   #include <rte_kni_common.h>
> >
> 
> <...>