From: Olivier MATZ <olivier.matz@6wind.com>
To: Sergio Gonzalez Monroy <sergio.gonzalez.monroy@intel.com>, dev@dpdk.org
Subject: Re: [dpdk-dev] [PATCH 2/2] Remove RTE_MBUF_REFCNT references
Date: Wed, 18 Feb 2015 10:16:56 +0100 [thread overview]
Message-ID: <54E45888.7070603@6wind.com> (raw)
In-Reply-To: <1424102913-18944-3-git-send-email-sergio.gonzalez.monroy@intel.com>
Hi Sergio,
On 02/16/2015 05:08 PM, Sergio Gonzalez Monroy wrote:
> This patch removes all references to RTE_MBUF_REFCNT, setting the refcnt
> field in the mbuf struct permanently.
>
> Signed-off-by: Sergio Gonzalez Monroy <sergio.gonzalez.monroy@intel.com>
I think removing the refcount compile option goes in the right
direction. However, activating the refcount will break the applications
that reserve a private zone in mbufs. This is due to the macros
RTE_MBUF_TO_BADDR() and RTE_MBUF_FROM_BADDR() that suppose that
the beginning of the mbuf is 128 bytes (sizeof mbuf) before the
data buffer.
For RTE_MBUF_TO_BADDR(), it's relatively easy to replace it. The
mbuf pool could store the size of the private size like it's done
for mbp_priv->mbuf_data_room_size. Using rte_mempool_from_obj(m)
or m->pool, we can retrieve the mbuf pool and this value, then
compute the buffer address.
For RTE_MBUF_FROM_BADDR(), it's more complex. We could ensure that
a backpointer to the mbuf is always located before the data buffer,
but it looks difficult to do.
Another idea would be to add a field in indirect mbufs that stores
the pointer to the "parent" mbuf.
Regards,
Olivier
next prev parent reply other threads:[~2015-02-18 9:16 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-02-16 16:08 [dpdk-dev] [PATCH 0/2] Removal of RTE_MBUF_REFCNT Sergio Gonzalez Monroy
2015-02-16 16:08 ` [dpdk-dev] [PATCH 1/2] mbuf: Introduce IND_ATTACHED_MBUF flag Sergio Gonzalez Monroy
2015-02-16 16:08 ` [dpdk-dev] [PATCH 2/2] Remove RTE_MBUF_REFCNT references Sergio Gonzalez Monroy
2015-02-18 9:16 ` Olivier MATZ [this message]
2015-02-18 9:35 ` Bruce Richardson
2015-02-18 9:48 ` Ananyev, Konstantin
2015-02-18 10:00 ` Bruce Richardson
2015-02-18 10:14 ` Olivier MATZ
2015-02-18 10:22 ` Ananyev, Konstantin
2015-02-18 10:22 ` Bruce Richardson
2015-02-18 10:33 ` Olivier MATZ
2015-02-18 10:37 ` Bruce Richardson
2015-02-18 10:47 ` Olivier MATZ
2015-02-18 10:47 ` Ananyev, Konstantin
2015-02-18 11:01 ` Olivier MATZ
2015-02-18 9:52 ` Olivier MATZ
2015-02-16 20:47 ` [dpdk-dev] [PATCH 0/2] Removal of RTE_MBUF_REFCNT Stephen Hemminger
2015-02-17 8:43 ` Gonzalez Monroy, Sergio
2015-02-18 11:03 ` [dpdk-dev] [PATCH v2 " Sergio Gonzalez Monroy
2015-02-18 11:03 ` [dpdk-dev] [PATCH v2 1/2] mbuf: Introduce IND_ATTACHED_MBUF flag Sergio Gonzalez Monroy
2015-02-18 11:03 ` [dpdk-dev] [PATCH v2 2/2] Remove RTE_MBUF_REFCNT references Sergio Gonzalez Monroy
2015-02-18 12:05 ` [dpdk-dev] [PATCH v2 0/2] Removal of RTE_MBUF_REFCNT Ananyev, Konstantin
2015-02-23 18:36 ` Thomas Monjalon
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=54E45888.7070603@6wind.com \
--to=olivier.matz@6wind.com \
--cc=dev@dpdk.org \
--cc=sergio.gonzalez.monroy@intel.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).