From: "Ananyev, Konstantin" <konstantin.ananyev@intel.com>
To: Olivier MATZ <olivier.matz@6wind.com>
Cc: "dev@dpdk.org" <dev@dpdk.org>
Subject: Re: [dpdk-dev] [PATCH v2 1/5] mbuf: fix clone support when application uses private mbuf data
Date: Wed, 1 Apr 2015 13:48:20 +0000 [thread overview]
Message-ID: <2601191342CEEE43887BDE71AB9772582141368A@irsmsx105.ger.corp.intel.com> (raw)
In-Reply-To: <551AEF08.8020009@6wind.com>
> -----Original Message-----
> From: Olivier MATZ [mailto:olivier.matz@6wind.com]
> Sent: Tuesday, March 31, 2015 8:01 PM
> To: Ananyev, Konstantin
> Cc: dev@dpdk.org
> Subject: Re: [dpdk-dev] [PATCH v2 1/5] mbuf: fix clone support when application uses private mbuf data
>
> Hi Konstantin,
>
> On 03/31/2015 01:17 AM, Ananyev, Konstantin wrote:
> >>>> With this solution, there are 2 options:
> >>>> - no mempool modification, so each application/driver has to add
> >>>> priv_size bytes to the object to get the mbuf pointer. This does not
> >>>> look feasible.
> >>>> - change the mempool to support private area before each object. I
> >>>> think mempool API is already quite complex, and I think it's not
> >>>> the role of the mempool library to provide such features.
> >>>
> >>>
> >>> In fact, I think the changes would be minimal.
> >>> All we have to do, is to make changes in rte_pktmbuf_init():
> >>>
> >>> void
> >>> rte_pktmbuf_init(struct rte_mempool *mp,
> >>> __attribute__((unused)) void *opaque_arg,
> >>> void *_m,
> >>> __attribute__((unused)) unsigned i)
> >>> {
> >>>
> >>> //extract priv_size from mempool (discussed above).
> >>> uint16_t priv_size = rte_mbufpool_get_priv_size(mp);
> >>>
> >>> struct rte_mbuf *m = _m + priv_size;
> >>> uint32_t buf_len = mp->elt_size - sizeof(struct rte_mbuf) - priv_size;
> >>>
> >>> ....
> >>>
> >>>
> >>> With that way priv_size inside mbuf would always be the size its own private space,
> >>> for both direct and indirect mbus., so we don't require to set priv_size at attach/detach.
> >>> Again RTE_MBUF_TO_BADDR() and RTE_MBUF_FROM_BADDR() would just work without any modifications.
> >>
> >> I'm not sure I'm getting it. The argument '_m' of your
> >> rte_pktmbuf_init() is the pointer to the priv data, right?
> >> So it means that the mbuf is located priv_size bytes after.
> >>
> >> The rte_pktmbuf_init() function is called by mempool_create(),
> >> and the _m parameter is a pointer to a mempool object. So
> >> in my understanding, mempool_get() would not return a rte_mbuf
> >> but a pointer to the application private data.
> >
> > Ah my bad, forgot that mempool's obj_init() returns void now :(
> > To make this approach work also need to change it, so it return a pointer to the new object.
> > So, rte_pktmbuf_init() would return m and then in mempool_add_elem():
> >
> > if (obj_init)
> > obj = obj_init(mp, obj_init_arg, obj, obj_idx);
> >
> > rte_ring_sp_enqueue(mp->ring, obj);
>
> Yes, but modififying mempool is what I wanted to avoid for several
> reasons. First, I think that changing the mempool_create() API here
> (actually the obj_init prototype) would impact existing applications.
>
> Also, I'm afraid that storing a different address than the start
> address of the object would have additional impacts. For instance,
> some data is supposed to be stored before the object, see
> __mempool_from_obj() or mempool_obj_audit().
mempool_obj_audit() should be ok, I think, but yes -
rte_mempool_from_obj() would change the behaviour and
can't be used by mempool_obj_audit() anymore.
Ok, I am convinced - let's stick with private space between rte_mbuf and buf_adddr, as you suggested.
>
> Finally, I believe that mempool is not the proper place to do
> modifications that are only needed for mbufs. If we really want
> to implement mbuf private data in that way, maybe it would be
> better to add a new layer above mempool (a mbuf pool layer).
Not that I am against it, but seems like even more massive change -
every application would need to be changed to use rte_mbufpool_create(), no?
Konstantin
>
>
> Regards
> Olivier
next prev parent reply other threads:[~2015-04-01 13:48 UTC|newest]
Thread overview: 101+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-03-25 17:00 [dpdk-dev] [PATCH 0/5] mbuf: enhancements of mbuf clones Olivier Matz
2015-03-25 17:00 ` [dpdk-dev] [PATCH 1/5] mbuf: fix clone support when application uses private mbuf data Olivier Matz
2015-03-26 13:35 ` Bruce Richardson
2015-03-26 15:30 ` Olivier MATZ
2015-03-25 17:00 ` [dpdk-dev] [PATCH 2/5] mbuf: allow to clone an indirect mbuf Olivier Matz
2015-03-25 17:00 ` [dpdk-dev] [PATCH 3/5] test/mbuf: rename mc variable in m Olivier Matz
2015-03-25 17:00 ` [dpdk-dev] [PATCH 4/5] test/mbuf: enhance mbuf refcnt test Olivier Matz
2015-03-25 17:00 ` [dpdk-dev] [PATCH 5/5] test/mbuf: verify that cloning a clone works properly Olivier Matz
2015-03-26 8:48 ` Olivier MATZ
2015-03-26 15:59 ` [dpdk-dev] [PATCH v2 0/5] mbuf: enhancements of mbuf clones Olivier Matz
2015-03-26 15:59 ` [dpdk-dev] [PATCH v2 1/5] mbuf: fix clone support when application uses private mbuf data Olivier Matz
2015-03-26 17:13 ` Zoltan Kiss
2015-03-27 0:24 ` Ananyev, Konstantin
2015-03-27 9:07 ` Olivier MATZ
2015-03-27 13:56 ` Olivier MATZ
2015-03-27 14:25 ` Ananyev, Konstantin
2015-03-27 15:17 ` Olivier MATZ
2015-03-27 18:11 ` Zoltan Kiss
2015-03-28 21:19 ` Olivier MATZ
2015-03-30 12:34 ` Ananyev, Konstantin
2015-03-30 19:55 ` Olivier MATZ
2015-03-30 23:17 ` Ananyev, Konstantin
2015-03-31 19:01 ` Olivier MATZ
2015-04-01 13:48 ` Ananyev, Konstantin [this message]
2015-04-01 15:18 ` Olivier MATZ
2015-03-26 15:59 ` [dpdk-dev] [PATCH v2 2/5] mbuf: allow to clone an indirect mbuf Olivier Matz
2015-03-26 15:59 ` [dpdk-dev] [PATCH v2 3/5] test/mbuf: rename mc variable in m Olivier Matz
2015-03-26 15:59 ` [dpdk-dev] [PATCH v2 4/5] test/mbuf: enhance mbuf refcnt test Olivier Matz
2015-03-26 15:59 ` [dpdk-dev] [PATCH v2 5/5] test/mbuf: verify that cloning a clone works properly Olivier Matz
2015-03-31 19:22 ` [dpdk-dev] [PATCH v3 0/5] mbuf: enhancements of mbuf clones Olivier Matz
2015-03-31 19:23 ` [dpdk-dev] [PATCH v3 1/5] mbuf: fix clone support when application uses private mbuf data Olivier Matz
2015-04-02 14:32 ` Zoltan Kiss
2015-04-02 17:21 ` Ananyev, Konstantin
2015-04-06 21:49 ` Olivier MATZ
2015-04-07 12:40 ` Ananyev, Konstantin
2015-04-07 15:45 ` Olivier MATZ
2015-04-07 17:17 ` Ananyev, Konstantin
2015-04-08 9:44 ` Olivier MATZ
2015-04-08 13:45 ` Ananyev, Konstantin
2015-04-09 13:06 ` Olivier MATZ
2015-04-20 15:41 ` [dpdk-dev] [PATCH v4 00/12] mbuf: enhancements of mbuf clones Olivier Matz
2015-04-20 15:41 ` [dpdk-dev] [PATCH v4 01/12] mbuf: fix mbuf data room size calculation rte_pktmbuf_pool_init Olivier Matz
2015-04-20 15:41 ` [dpdk-dev] [PATCH v4 02/12] examples: always initialize mbuf_pool private area Olivier Matz
2015-04-20 15:41 ` [dpdk-dev] [PATCH v4 03/12] mbuf: add accessors to get data room size and private size Olivier Matz
2015-04-20 15:41 ` [dpdk-dev] [PATCH v4 04/12] mbuf: fix rte_pktmbuf_init when mbuf private size is not zero Olivier Matz
2015-04-20 15:41 ` [dpdk-dev] [PATCH v4 05/12] testpmd: use standard functions to initialize mbufs and mbuf pool Olivier Matz
2015-04-20 15:41 ` [dpdk-dev] [PATCH v4 06/12] mbuf: introduce a new helper to create a " Olivier Matz
2015-04-20 15:41 ` [dpdk-dev] [PATCH v4 07/12] apps: use rte_pktmbuf_pool_create to create mbuf pools Olivier Matz
2015-04-20 15:41 ` [dpdk-dev] [PATCH v4 08/12] mbuf: fix clone support when application uses private mbuf data Olivier Matz
2015-04-20 15:41 ` [dpdk-dev] [PATCH v4 09/12] mbuf: allow to clone an indirect mbuf Olivier Matz
2015-04-20 15:41 ` [dpdk-dev] [PATCH v4 10/12] test/mbuf: rename mc variable in m Olivier Matz
2015-04-20 15:41 ` [dpdk-dev] [PATCH v4 11/12] test/mbuf: enhance mbuf refcnt test Olivier Matz
2015-04-20 15:41 ` [dpdk-dev] [PATCH v4 12/12] test/mbuf: verify that cloning a clone works properly Olivier Matz
2015-04-20 16:53 ` [dpdk-dev] [PATCH v4 00/12] mbuf: enhancements of mbuf clones Neil Horman
2015-04-20 17:07 ` Olivier MATZ
2015-04-20 17:21 ` Neil Horman
2015-04-20 18:24 ` Olivier MATZ
2015-04-21 9:55 ` [dpdk-dev] [PATCH v5 " Olivier Matz
2015-04-21 9:55 ` [dpdk-dev] [PATCH v5 01/12] mbuf: fix mbuf data room size calculation rte_pktmbuf_pool_init Olivier Matz
2015-04-21 9:55 ` [dpdk-dev] [PATCH v5 02/12] examples: always initialize mbuf_pool private area Olivier Matz
2015-04-21 9:55 ` [dpdk-dev] [PATCH v5 03/12] mbuf: add accessors to get data room size and private size Olivier Matz
2015-04-21 9:55 ` [dpdk-dev] [PATCH v5 04/12] mbuf: fix rte_pktmbuf_init when mbuf private size is not zero Olivier Matz
2015-04-21 15:07 ` Ananyev, Konstantin
2015-04-21 9:55 ` [dpdk-dev] [PATCH v5 05/12] testpmd: use standard functions to initialize mbufs and mbuf pool Olivier Matz
2015-04-21 9:55 ` [dpdk-dev] [PATCH v5 06/12] mbuf: introduce a new helper to create a " Olivier Matz
2015-04-21 9:55 ` [dpdk-dev] [PATCH v5 07/12] apps: use rte_pktmbuf_pool_create to create mbuf pools Olivier Matz
2015-04-21 9:55 ` [dpdk-dev] [PATCH v5 08/12] mbuf: fix clone support when application uses private mbuf data Olivier Matz
2015-04-21 15:01 ` Ananyev, Konstantin
2015-04-21 15:26 ` Olivier MATZ
2015-04-21 9:55 ` [dpdk-dev] [PATCH v5 09/12] mbuf: allow to clone an indirect mbuf Olivier Matz
2015-04-21 9:55 ` [dpdk-dev] [PATCH v5 10/12] test/mbuf: rename mc variable in m Olivier Matz
2015-04-21 9:55 ` [dpdk-dev] [PATCH v5 11/12] test/mbuf: enhance mbuf refcnt test Olivier Matz
2015-04-21 9:55 ` [dpdk-dev] [PATCH v5 12/12] test/mbuf: verify that cloning a clone works properly Olivier Matz
2015-04-21 11:50 ` [dpdk-dev] [PATCH v5 00/12] mbuf: enhancements of mbuf clones Neil Horman
2015-04-22 9:57 ` [dpdk-dev] [PATCH v6 00/13] " Olivier Matz
2015-04-22 9:57 ` [dpdk-dev] [PATCH v6 01/13] mbuf: fix mbuf data room size calculation rte_pktmbuf_pool_init Olivier Matz
2015-04-22 9:57 ` [dpdk-dev] [PATCH v6 02/13] examples: always initialize mbuf_pool private area Olivier Matz
2015-04-22 9:57 ` [dpdk-dev] [PATCH v6 03/13] mbuf: add accessors to get data room size and private size Olivier Matz
2015-04-28 9:15 ` Thomas Monjalon
2015-04-22 9:57 ` [dpdk-dev] [PATCH v6 04/13] mbuf: fix rte_pktmbuf_init when mbuf private size is not zero Olivier Matz
2015-04-22 9:57 ` [dpdk-dev] [PATCH v6 05/13] testpmd: use standard functions to initialize mbufs and mbuf pool Olivier Matz
2015-04-22 9:57 ` [dpdk-dev] [PATCH v6 06/13] mbuf: introduce a new helper to create a " Olivier Matz
2015-04-22 9:57 ` [dpdk-dev] [PATCH v6 07/13] apps: use rte_pktmbuf_pool_create to create mbuf pools Olivier Matz
2015-04-22 9:57 ` [dpdk-dev] [PATCH v6 08/13] mbuf: fix clone support when application uses private mbuf data Olivier Matz
2015-04-22 9:57 ` [dpdk-dev] [PATCH v6 09/13] mbuf: allow to clone an indirect mbuf Olivier Matz
2015-04-22 9:57 ` [dpdk-dev] [PATCH v6 10/13] test/mbuf: rename mc variable in m Olivier Matz
2015-04-22 9:57 ` [dpdk-dev] [PATCH v6 11/13] test/mbuf: enhance mbuf refcnt test Olivier Matz
2015-04-22 9:57 ` [dpdk-dev] [PATCH v6 12/13] test/mbuf: verify that cloning a clone works properly Olivier Matz
2015-04-22 9:57 ` [dpdk-dev] [PATCH v6 13/13] test/mbuf: add a test case for clone with different priv size Olivier Matz
2015-04-22 11:59 ` [dpdk-dev] [PATCH v6 00/13] mbuf: enhancements of mbuf clones Ananyev, Konstantin
2015-04-24 10:38 ` Zoltan Kiss
2015-04-27 17:38 ` Thomas Monjalon
2015-04-28 11:15 ` Zoltan Kiss
2015-05-07 1:57 ` Xu, HuilongX
2015-05-07 7:32 ` Olivier MATZ
2015-05-07 9:39 ` Ananyev, Konstantin
2015-04-28 9:50 ` Thomas Monjalon
2015-03-31 19:23 ` [dpdk-dev] [PATCH v3 2/5] mbuf: allow to clone an indirect mbuf Olivier Matz
2015-03-31 19:23 ` [dpdk-dev] [PATCH v3 3/5] test/mbuf: rename mc variable in m Olivier Matz
2015-03-31 19:23 ` [dpdk-dev] [PATCH v3 4/5] test/mbuf: enhance mbuf refcnt test Olivier Matz
2015-03-31 19:23 ` [dpdk-dev] [PATCH v3 5/5] test/mbuf: verify that cloning a clone works properly Olivier Matz
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