From: Felix Fietkau <nbd@nbd.name>
To: Andrew Lunn <andrew@lunn.ch>
Cc: netdev@vger.kernel.org, Sean Wang <sean.wang@mediatek.com>,
Mark Lee <Mark-MC.Lee@mediatek.com>,
Lorenzo Bianconi <lorenzo@kernel.org>,
"David S. Miller" <davem@davemloft.net>,
Eric Dumazet <edumazet@google.com>,
Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
Matthias Brugger <matthias.bgg@gmail.com>,
AngeloGioacchino Del Regno
<angelogioacchino.delregno@collabora.com>,
linux-kernel@vger.kernel.org,
linux-arm-kernel@lists.infradead.org,
linux-mediatek@lists.infradead.org
Subject: Re: [PATCH net-next 4/4] net: ethernet: mtk_eth_soc: optimize dma ring address/index calculation
Date: Tue, 15 Oct 2024 15:07:50 +0200 [thread overview]
Message-ID: <695421bb-6f31-4bae-8c8c-6d4fccf1b497@nbd.name> (raw)
In-Reply-To: <e67883e3-b278-4052-849c-8a9a8ef145f0@lunn.ch>
On 15.10.24 14:54, Andrew Lunn wrote:
> On Tue, Oct 15, 2024 at 01:09:38PM +0200, Felix Fietkau wrote:
>> Since DMA descriptor sizes are all power of 2, we can avoid costly integer
>> division in favor or simple shifts.
>
> Could a BUILD_BUG_ON() be added to validate this?
Not sure if that would be useful. I can't put the BUILD_BUG_ON in the
initializer macro, so I could only add it for the individual dma
descriptor structs.
Since the size of those structs will not be changed (otherwise it would
immediately visibly break with existing hw), the remaining possibility
would be adding new structs that violate this expectation. However,
those would then not be covered by the BUILD_BUG_ON.
> Do you have some benchmark data for this series? It would be good to
> add to a patch 0/4.
No, I just ran basic tests that everything still works well and looked
at the assembly diff to ensure that the generated code seems sane.
- Felix
next prev parent reply other threads:[~2024-10-15 13:08 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-10-15 11:09 [PATCH net-next 1/4] net: ethernet: mtk_eth_soc: compile out netsys v2+ code on mt7621 Felix Fietkau
2024-10-15 11:09 ` [PATCH net-next 2/4] net: ethernet: mtk_eth_soc: use napi_build_skb() Felix Fietkau
2024-10-15 11:09 ` [PATCH net-next 3/4] net: ethernet: mtk_eth_soc: reduce rx ring size for older chipsets Felix Fietkau
2024-10-15 11:09 ` [PATCH net-next 4/4] net: ethernet: mtk_eth_soc: optimize dma ring address/index calculation Felix Fietkau
2024-10-15 12:54 ` Andrew Lunn
2024-10-15 13:07 ` Felix Fietkau [this message]
2024-10-21 9:23 ` Paolo Abeni
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=695421bb-6f31-4bae-8c8c-6d4fccf1b497@nbd.name \
--to=nbd@nbd.name \
--cc=Mark-MC.Lee@mediatek.com \
--cc=andrew@lunn.ch \
--cc=angelogioacchino.delregno@collabora.com \
--cc=davem@davemloft.net \
--cc=edumazet@google.com \
--cc=kuba@kernel.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mediatek@lists.infradead.org \
--cc=lorenzo@kernel.org \
--cc=matthias.bgg@gmail.com \
--cc=netdev@vger.kernel.org \
--cc=pabeni@redhat.com \
--cc=sean.wang@mediatek.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