patches for DPDK stable branches
 help / color / mirror / Atom feed
From: Raslan Darawsheh <rasland@nvidia.com>
To: Slava Ovsiienko <viacheslavo@nvidia.com>, "dev@dpdk.org" <dev@dpdk.org>
Cc: Matan Azrad <matan@nvidia.com>, Ori Kam <orika@nvidia.com>,
	"stable@dpdk.org" <stable@dpdk.org>
Subject: RE: [PATCH] net/mlx5: fix read device clock in real time mode
Date: Sun, 8 Jan 2023 12:59:54 +0000	[thread overview]
Message-ID: <BYAPR12MB3078B1D0CCD9EF205AA400D7CFF99@BYAPR12MB3078.namprd12.prod.outlook.com> (raw)
In-Reply-To: <20230103111145.29824-1-viacheslavo@nvidia.com>

Hi,

> -----Original Message-----
> From: Slava Ovsiienko <viacheslavo@nvidia.com>
> Sent: Tuesday, January 3, 2023 1:12 PM
> To: dev@dpdk.org
> Cc: Matan Azrad <matan@nvidia.com>; Raslan Darawsheh
> <rasland@nvidia.com>; Ori Kam <orika@nvidia.com>; stable@dpdk.org
> Subject: [PATCH] net/mlx5: fix read device clock in real time mode
> 
> Since ConnectX-6DX the real time timestamp mode is supported.
> The rte_eth_read_clock() routine queries current timestamp value from the
> PMD.
> 
> The mlx5 PMD has special infrastructure to schedule packet sending in real
> time mode which can be engaged with tx_pp devarg.
> This infrastructure provides the timestamp reading from the special queue
> CEQs directly from the host memory in user space, without involving kernel
> calls.
> 
> The ConnectX-7 NIC has hardware capability to schedule packet sending
> without special infrastructure and tx_pp devarg can be omitted. If there is no
> tx_pp devarg specified the mlx5 uses kernel calls to query current timestamp
> value. The kernel can be completely unaware about engaged real time
> mode, also kernel might use its internal queue CQEs to get timestamps, that
> is neither precise nor reliable, inconsistent values might be returned, causing
> send scheduling malfunction.
> 
> The HCA PCI BAR provides the real time direct reading from hardware.
> This patch maps PCI resource to the process address space on demand and
> allows reading the real time timestamp values from the NIC directly.
> 
> Fixes: b94d93ca73803 ("net/mlx5: support reading device clock")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Viacheslav Ovsiienko <viacheslavo@nvidia.com>

Patch applied to next-net-mlx,

Kindest regards,
Raslan Darawsheh

      reply	other threads:[~2023-01-08 12:59 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-01-03 11:11 Viacheslav Ovsiienko
2023-01-08 12:59 ` Raslan Darawsheh [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=BYAPR12MB3078B1D0CCD9EF205AA400D7CFF99@BYAPR12MB3078.namprd12.prod.outlook.com \
    --to=rasland@nvidia.com \
    --cc=dev@dpdk.org \
    --cc=matan@nvidia.com \
    --cc=orika@nvidia.com \
    --cc=stable@dpdk.org \
    --cc=viacheslavo@nvidia.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).