From: Dmitry Kozlyuk <dmitry.kozliuk@gmail.com>
To: fwefew 4t4tg <7532yahoo@gmail.com>
Cc: users@dpdk.org
Subject: Re: DPDK and DMA
Date: Wed, 11 Jan 2023 23:14:27 +0300 [thread overview]
Message-ID: <20230111231427.23b209a8@sovereign> (raw)
In-Reply-To: <CA+Tq66V+_cWx9jRR9mJ7Y=pkkoBngn+HfHVko4zBACgbKKYURw@mail.gmail.com>
2023-01-11 13:05 (UTC-0500), fwefew 4t4tg:
> Thank you for taking time to provide a nice reply. The upshot here is that
> DPDK
> already uses DMA in a smart way to move packet data into TXQs. I presume the
> reverse also happens: NIC uses DMA to move packets out of its HW RXQs into
> the host machine's memory using the mempool associated with it.
Almost, except that the NIC does not know about mempools.
It's DPDK PMD (as Stephen clarified) that allocates mbufs from mempool,
does Rx descriptor setup to point to the buffers
and then requests the NIC to write packet data to host RAM using DMA.
If you want to study this area, take a look at "ixy" project family:
https://github.com/ixy-languages/ixy-languages
It's like "micro DPDK" for educational purposes.
prev parent reply other threads:[~2023-01-11 20:14 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-01-08 21:05 fwefew 4t4tg
2023-01-11 11:26 ` Dmitry Kozlyuk
2023-01-11 18:05 ` fwefew 4t4tg
2023-01-11 18:54 ` Stephen Hemminger
2023-01-11 20:14 ` Dmitry Kozlyuk [this message]
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