Netdev List
 help / color / mirror / Atom feed
From: David Woodhouse <dwmw2@infradead.org>
To: Will Deacon <will@kernel.org>, linux-kernel@vger.kernel.org
Cc: "Keir Fraser" <keirf@google.com>,
	"Steven Moreland" <smoreland@google.com>,
	"Frederick Mayle" <fmayle@google.com>,
	"Stefan Hajnoczi" <stefanha@redhat.com>,
	"Stefano Garzarella" <sgarzare@redhat.com>,
	"Michael S. Tsirkin" <mst@redhat.com>,
	"Jason Wang" <jasowang@redhat.com>,
	"Eugenio Pérez" <eperezma@redhat.com>,
	netdev@vger.kernel.org, virtualization@lists.linux.dev
Subject: Re: [PATCH v4 4/9] vsock/virtio: Resize receive buffers so that each SKB fits in a 4K page
Date: Thu, 08 Jan 2026 17:33:42 +0100	[thread overview]
Message-ID: <fa3cd687961e63dd2b79780eb84c243c8d35532a.camel@infradead.org> (raw)
In-Reply-To: <20250717090116.11987-5-will@kernel.org>

[-- Attachment #1: Type: text/plain, Size: 705 bytes --]

On Thu, 2025-07-17 at 10:01 +0100, Will Deacon wrote:
> 
> -#define VIRTIO_VSOCK_DEFAULT_RX_BUF_SIZE	(1024 * 4)
> +/* Dimension the RX SKB so that the entire thing fits exactly into
> + * a single 4KiB page. This avoids wasting memory due to alloc_skb()
> + * rounding up to the next page order and also means that we
> + * don't leave higher-order pages sitting around in the RX queue.
> + */
> +#define
> VIRTIO_VSOCK_DEFAULT_RX_BUF_SIZE	SKB_WITH_OVERHEAD(1024 * 4)

Should this be SKB_WITH_OVERHEAD()?

Or should it subtract VIRTIO_VSOCK_SKB_HEADROOM instead?

(And also, I have use cases where I want to expand this to 64KiB. Can I
make it controllable with a sockopt? module param?)

[-- Attachment #2: smime.p7s --]
[-- Type: application/pkcs7-signature, Size: 5069 bytes --]

  reply	other threads:[~2026-01-08 16:33 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-07-17  9:01 [PATCH v4 0/9] vsock/virtio: SKB allocation improvements Will Deacon
2025-07-17  9:01 ` [PATCH v4 1/9] vhost/vsock: Avoid allocating arbitrarily-sized SKBs Will Deacon
2025-07-17  9:10   ` Jason Wang
2025-07-17  9:25     ` Stefano Garzarella
2025-07-17  9:01 ` [PATCH v4 2/9] vsock/virtio: Validate length in packet header before skb_put() Will Deacon
2025-07-17  9:39   ` Stefano Garzarella
2025-07-17  9:01 ` [PATCH v4 3/9] vsock/virtio: Move length check to callers of virtio_vsock_skb_rx_put() Will Deacon
2025-07-17  9:01 ` [PATCH v4 4/9] vsock/virtio: Resize receive buffers so that each SKB fits in a 4K page Will Deacon
2026-01-08 16:33   ` David Woodhouse [this message]
2026-01-12 14:48     ` Stefano Garzarella
2026-01-12 15:22       ` Will Deacon
2025-07-17  9:01 ` [PATCH v4 5/9] vsock/virtio: Rename virtio_vsock_alloc_skb() Will Deacon
2025-07-17  9:01 ` [PATCH v4 6/9] vsock/virtio: Move SKB allocation lower-bound check to callers Will Deacon
2025-07-17  9:01 ` [PATCH v4 7/9] vhost/vsock: Allocate nonlinear SKBs for handling large receive buffers Will Deacon
2025-07-17  9:01 ` [PATCH v4 8/9] vsock/virtio: Rename virtio_vsock_skb_rx_put() Will Deacon
2025-07-17  9:01 ` [PATCH v4 9/9] vsock/virtio: Allocate nonlinear SKBs for handling large transmit buffers Will Deacon
2025-08-13  8:41   ` Michael S. Tsirkin
2025-08-13 13:25     ` Hillf Danton
2025-08-15 10:22       ` Michael S. Tsirkin
2025-08-15 12:07         ` Hillf Danton
2025-08-16 10:38           ` Michael S. Tsirkin
2025-07-17 12:31 ` [PATCH v4 0/9] vsock/virtio: SKB allocation improvements Michael S. Tsirkin
2025-07-17 12:36   ` Stefano Garzarella
2025-07-17 12:35 ` Michael S. Tsirkin

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=fa3cd687961e63dd2b79780eb84c243c8d35532a.camel@infradead.org \
    --to=dwmw2@infradead.org \
    --cc=eperezma@redhat.com \
    --cc=fmayle@google.com \
    --cc=jasowang@redhat.com \
    --cc=keirf@google.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mst@redhat.com \
    --cc=netdev@vger.kernel.org \
    --cc=sgarzare@redhat.com \
    --cc=smoreland@google.com \
    --cc=stefanha@redhat.com \
    --cc=virtualization@lists.linux.dev \
    --cc=will@kernel.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