DPDK patches and discussions
 help / color / mirror / Atom feed
From: "Morten Brørup" <mb@smartsharesystems.com>
To: "Ferruh Yigit" <ferruh.yigit@amd.com>,
	"Du, Frank" <frank.du@intel.com>, <dev@dpdk.org>,
	"Andrew Rybchenko" <andrew.rybchenko@oktetlabs.ru>
Cc: "Loftus, Ciara" <ciara.loftus@intel.com>,
	"Burakov, Anatoly" <anatoly.burakov@intel.com>
Subject: RE: [PATCH v2] net/af_xdp: fix umem map size for zero copy
Date: Wed, 22 May 2024 13:03:28 +0200	[thread overview]
Message-ID: <98CBD80474FA8B44BF855DF32C47DC35E9F48B@smartserver.smartshare.dk> (raw)
In-Reply-To: <36e654fe-078e-4df3-bb2f-de3917da3e17@amd.com>

> From: Ferruh Yigit [mailto:ferruh.yigit@amd.com]
> Sent: Wednesday, 22 May 2024 12.01
> 
> On 5/22/2024 2:25 AM, Du, Frank wrote:
> >> From: Ferruh Yigit <ferruh.yigit@amd.com>
> >> Sent: Wednesday, May 22, 2024 1:58 AM
> >>
> >> Isn't there a mempool flag that can help us figure out mempool is not IOVA
> >> contiguous? Isn't it sufficient on its own?
> >
> > Indeed, what we need to ascertain is whether it's contiguous in CPU virtual
> space, not IOVA. I haven't come across a flag specifically for CPU virtual
> contiguity. The major limitation in XDP is XSK UMEM only supports registering
> a single contiguous virtual memory area.
> >
> 
> 'RTE_MEMPOOL_F_NO_IOVA_CONTIG' is the flag I was looking for. This flag
> being *cleared* implies IOVA contiguous but not sure if it is
> guaranteed, need to check.

Wrong.
RTE_MEMPOOL_F_NO_IOVA_CONTIG only relates to individual objects in the pool. This flag being cleared only means that each individual object in the mempool is IOVA contiguous.
It does not imply that the entire pool of objects is IOVA contiguous.

> 
> And I may be wrong here, but as far as I remember in IOVA as VA mode,
> process virtual address and IOVA address are same, so IOVA contiguous is
> same as contiguous CPU virtual address.


  reply	other threads:[~2024-05-22 11:03 UTC|newest]

Thread overview: 26+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-04-26  0:51 [PATCH] " Frank Du
2024-04-26 10:43 ` Loftus, Ciara
2024-04-28  0:46   ` Du, Frank
2024-04-30  9:22     ` Loftus, Ciara
2024-05-11  5:26 ` [PATCH v2] " Frank Du
2024-05-17 13:19   ` Loftus, Ciara
2024-05-20  1:28     ` Du, Frank
2024-05-21 15:43   ` Ferruh Yigit
2024-05-21 17:57   ` Ferruh Yigit
2024-05-22  1:25     ` Du, Frank
2024-05-22  7:26       ` Morten Brørup
2024-05-22 10:20         ` Ferruh Yigit
2024-05-23  6:56         ` Du, Frank
2024-05-23  7:40           ` Morten Brørup
2024-05-23  7:56             ` Du, Frank
2024-05-29 12:57               ` Loftus, Ciara
2024-05-29 14:16                 ` Morten Brørup
2024-05-22 10:00       ` Ferruh Yigit
2024-05-22 11:03         ` Morten Brørup [this message]
2024-05-22 14:05           ` Ferruh Yigit
2024-05-23  6:53 ` [PATCH v3] " Frank Du
2024-05-23  8:07 ` [PATCH v4] " Frank Du
2024-05-23  9:22   ` Morten Brørup
2024-05-23 13:31     ` Ferruh Yigit
2024-05-24  1:05       ` Du, Frank
2024-05-24  5:30         ` 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=98CBD80474FA8B44BF855DF32C47DC35E9F48B@smartserver.smartshare.dk \
    --to=mb@smartsharesystems.com \
    --cc=anatoly.burakov@intel.com \
    --cc=andrew.rybchenko@oktetlabs.ru \
    --cc=ciara.loftus@intel.com \
    --cc=dev@dpdk.org \
    --cc=ferruh.yigit@amd.com \
    --cc=frank.du@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).