From: "Van Haaren, Harry" <harry.van.haaren@intel.com>
To: "songj@zctt.com" <songj@zctt.com>, "users@dpdk.org" <users@dpdk.org>
Subject: Re: [dpdk-users] How to getting first objects from a rte_mempool buffer every time?
Date: Wed, 20 Mar 2019 11:57:38 +0000 [thread overview]
Message-ID: <E923DB57A917B54B9182A2E928D00FA675807E00@IRSMSX102.ger.corp.intel.com> (raw)
In-Reply-To: <000001d4df09$e970f1e0$bc52d5a0$@zctt.com>+86DF114D4D1219DB
> -----Original Message-----
> From: users [mailto:users-bounces@dpdk.org] On Behalf Of ??
> Sent: Wednesday, March 20, 2019 10:45 AM
> To: users@dpdk.org
> Subject: [dpdk-users] How to getting first objects from a rte_mempool buffer
> every time?
>
> Hi all,
Hi Jie,
> I have a pcap file that contained 100 IP packets. I can send them by DPDK by
> below steps:
>
> 1. I create a rte_mempool buffer by rte_pktmbuf_pool_create. load these
> 100 packets into this buffer.
>
> 2. call rte_mempool_get_bulk to getting packets form rte_mempool buffer
> into rte_mbuf buffer,
>
> 3. put rte_mbuf buffer into rte_eth_tx_burst for sending .
>
> The pcap packets can be sent out from 1 to 100 Ok.
>
> Now I want to send the only first 10 packets every time,
>
> rte_mempool_get_bulk can get 1-10 objects, but next time it will get 11-20
> objects.
>
> I don’t know if there is easy way to getting first 10 objects from
> rte_mempool buffer every time?
The mempool data-structure is not designed for this usage.
If you require the first 10 items, I recommend dequeueing them from the
mempool once (as you have described above), and then caching them in another
data-structure to "loop" over them.
Typically an rte_ring would work well here, with the 10 items being dequeued
and re-enqueued over-and-over again to loop.
Note; when sending an mbuf via Ethdev, the refcount will be decremented,
and possibly the mbuf will be free()-ed and returned to the mempool.
If you wish to "keep" the mbuf in the rte_ring cache, consider incrementing
the refcount of the mbuf every time before you TX it - the result will be that
the mbuf is not freed back to the mempool, and remain valid to TX again.
> Thanks
> Jie
Hope that helps! -Harry
prev parent reply other threads:[~2019-03-20 11:57 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-03-20 10:44 宋捷
2019-03-20 11:57 ` Van Haaren, Harry [this message]
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=E923DB57A917B54B9182A2E928D00FA675807E00@IRSMSX102.ger.corp.intel.com \
--to=harry.van.haaren@intel.com \
--cc=songj@zctt.com \
--cc=users@dpdk.org \
/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).