DPDK patches and discussions
 help / color / mirror / Atom feed
From: Matan Azrad <matan@nvidia.com>
To: Ferruh Yigit <ferruh.yigit@intel.com>,
	Ray Kinsella <mdr@ashroe.eu>,
	"Neil Horman" <nhorman@tuxdriver.com>
Cc: "dev@dpdk.org" <dev@dpdk.org>,
	Konstantin Ananyev <konstantin.ananyev@intel.com>,
	NBU-Contact-Thomas Monjalon <thomas@monjalon.net>,
	Andrew Rybchenko <arybchenko@solarflare.com>,
	"Olivier Matz" <olivier.matz@6wind.com>,
	Jerin Jacob <jerinj@marvell.com>
Subject: Re: [dpdk-dev] [RFC v2] doc: announce max Rx packet len field deprecation
Date: Thu, 26 Nov 2020 18:30:56 +0000
Message-ID: <MW2PR12MB24929A1E8FA2C4A2619AAE9ADFF90@MW2PR12MB2492.namprd12.prod.outlook.com> (raw)
In-Reply-To: <20201124173628.1057348-1-ferruh.yigit@intel.com>



Hi

Looks very good direction - it will do some order here.

Will be also good to define what is MTU exactly:
Maximum Rx packet size \ Maximum Tx packet size \ both?
Is it include L2\L3 headers? Vlan?
How is it going together with ``uint32_t max_lro_pkt_size``?

Also when should the user configure DEV_RX_OFFLOAD_SCATTER?

Matan

From: Ferruh Yigit
> Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>
> Acked-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
> ---
> Cc: Thomas Monjalon <thomas@monjalon.net>
> Cc: Andrew Rybchenko <arybchenko@solarflare.com>
> Cc: Konstantin Ananyev <konstantin.ananyev@intel.com>
> Cc: Matan Azrad <matan@nvidia.com>
> Cc: Olivier Matz <olivier.matz@6wind.com>
> Cc: Jerin Jacob <jerinj@marvell.com>
> 
> v2:
> * ``uint32_t mtu`` moved to ``struct rte_eth_conf``
> * The "Driver is responsible from updating ``(struct
>   rte_eth_dev)->data->mtu``" updated because ethdev layer also can do
>   this. The intention there was both APIs should update the variable.
> 
> Another open question is from Andrew, if we can remove the ``uint32_t
> max_rx_pkt_len`` completely from the ``rte_eth_dev_configure()``.
> This may force applications to have one more additional
> ``rte_eth_dev_set_mtu()`` call for device initialization, but if applications are
> OK with the default values most of times, agree that removing is easier
> solution, please comment.
> ---
>  doc/guides/rel_notes/deprecation.rst | 25 +++++++++++++++++++++++++
>  1 file changed, 25 insertions(+)
> 
> diff --git a/doc/guides/rel_notes/deprecation.rst
> b/doc/guides/rel_notes/deprecation.rst
> index 96986fabd598..73e43581d615 100644
> --- a/doc/guides/rel_notes/deprecation.rst
> +++ b/doc/guides/rel_notes/deprecation.rst
> @@ -88,6 +88,31 @@ Deprecation Notices
>    will be limited to maximum 256 queues.
>    Also compile time flag ``RTE_ETHDEV_QUEUE_STAT_CNTRS`` will be
> removed.
> 
> +* ethdev: ``uint32_t max_rx_pkt_len`` field of ``struct
> +rte_eth_rxmode``, will be
> +  replaced by a new ``uint32_t mtu`` field of ``struct rte_eth_conf`` in v21.11.
> +  The new ``mtu`` field will be used to configure the initial device
> +MTU via
> +  ``rte_eth_dev_configure()`` API.
> +  Later MTU can be changed by ``rte_eth_dev_set_mtu()`` API as done now.
> +  The existing ``(struct rte_eth_dev)->data->mtu`` variable will be
> +used to store
> +  the configured ``mtu`` value,
> +  and this new ``(struct rte_eth_dev)->data->dev_conf.mtu`` variable
> +will
> +  be used to store the user configuration request.
> +  Unlike ``max_rx_pkt_len``, which was valid only when ``JUMBO_FRAME``
> +enabled,
> +  ``mtu`` field will be always valid.
> +  When ``mtu`` config is not provided by the application, default
> +``RTE_ETHER_MTU``
> +  value will be used.
> +  ``(struct rte_eth_dev)->data->mtu`` should be updated after MTU set
> +successfully,
> +  either by ``rte_eth_dev_configure()`` or ``rte_eth_dev_set_mtu()``.
> +
> +  An application may need to configure device for a specific Rx packet
> + size, like for  cases ``DEV_RX_OFFLOAD_SCATTER`` is not supported and
> + device received packet size  can't be bigger than Rx buffer size.
> +  To cover these cases an application needs to know the device packet
> + overhead to be  able to calculate the ``mtu`` corresponding to a Rx
> + buffer size, for this  ``(struct rte_eth_dev_info).max_rx_pktlen``
> + will be kept,  the device packet overhead can be calculated as:
> +  ``(struct rte_eth_dev_info).max_rx_pktlen - (struct
> + rte_eth_dev_info).max_mtu``
> +
>  * sched: To allow more traffic classes, flexible mapping of pipe queues to
>    traffic classes, and subport level configuration of pipes and queues
>    changes will be made to macros, data structures and API functions defined
> --
> 2.26.2


  parent reply	other threads:[~2020-11-26 18:31 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-10-20 12:03 [dpdk-dev] [RFC] " Ferruh Yigit
2020-10-21 10:18 ` Ananyev, Konstantin
2020-10-21 15:10   ` Andrew Rybchenko
2020-10-21 16:28     ` Ferruh Yigit
2020-10-21 12:40 ` Kinsella, Ray
2020-11-24 17:36 ` [dpdk-dev] [RFC v2] " Ferruh Yigit
2020-11-24 17:47   ` Ajit Khaparde
2020-11-26 11:28   ` Andrew Rybchenko
2020-11-26 12:34     ` Ferruh Yigit
2020-11-27 18:38       ` Thomas Monjalon
2020-11-26 18:30   ` Matan Azrad [this message]
2020-11-27  9:37     ` [dpdk-dev] [RFC v2] doc: announce max Rx packet len fielddeprecation Morten Brørup

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=MW2PR12MB24929A1E8FA2C4A2619AAE9ADFF90@MW2PR12MB2492.namprd12.prod.outlook.com \
    --to=matan@nvidia.com \
    --cc=arybchenko@solarflare.com \
    --cc=dev@dpdk.org \
    --cc=ferruh.yigit@intel.com \
    --cc=jerinj@marvell.com \
    --cc=konstantin.ananyev@intel.com \
    --cc=mdr@ashroe.eu \
    --cc=nhorman@tuxdriver.com \
    --cc=olivier.matz@6wind.com \
    --cc=thomas@monjalon.net \
    /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

DPDK patches and discussions

This inbox may be cloned and mirrored by anyone:

	git clone --mirror https://inbox.dpdk.org/dev/0 dev/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 dev dev/ https://inbox.dpdk.org/dev \
		dev@dpdk.org
	public-inbox-index dev

Example config snippet for mirrors.
Newsgroup available over NNTP:
	nntp://inbox.dpdk.org/inbox.dpdk.dev


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git