netdev - Re: [PATCH iwl-next v4 0/9] igc: Add support for Frame Preemption feature in IGC

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <87v7td3bi1.fsf@kurt.kurt.home>
Date: Thu, 13 Feb 2025 20:12:06 +0100
From: Kurt Kanzenbach <kurt@...utronix.de>
To: Vladimir Oltean <vladimir.oltean@....com>
Cc: "Abdul Rahim, Faizal" <faizal.abdul.rahim@...ux.intel.com>, Tony Nguyen
 <anthony.l.nguyen@...el.com>, Przemek Kitszel
 <przemyslaw.kitszel@...el.com>, Andrew Lunn <andrew+netdev@...n.ch>,
 "David S . Miller" <davem@...emloft.net>, Eric Dumazet
 <edumazet@...gle.com>, Jakub Kicinski <kuba@...nel.org>, Paolo Abeni
 <pabeni@...hat.com>, Maxime Coquelin <mcoquelin.stm32@...il.com>,
 Alexandre Torgue <alexandre.torgue@...s.st.com>, Simon Horman
 <horms@...nel.org>, Russell King <linux@...linux.org.uk>, Alexei
 Starovoitov <ast@...nel.org>, Daniel Borkmann <daniel@...earbox.net>,
 Jesper Dangaard Brouer <hawk@...nel.org>, John Fastabend
 <john.fastabend@...il.com>, Furong Xu <0x1207@...il.com>, Russell King
 <rmk+kernel@...linux.org.uk>, Serge Semin <fancer.lancer@...il.com>,
 Xiaolei Wang <xiaolei.wang@...driver.com>, Suraj Jaiswal
 <quic_jsuraj@...cinc.com>, Kory Maincent <kory.maincent@...tlin.com>, Gal
 Pressman <gal@...dia.com>, Jesper Nilsson <jesper.nilsson@...s.com>,
 Andrew Halaney <ahalaney@...hat.com>, Choong Yong Liang
 <yong.liang.choong@...ux.intel.com>, Kunihiko Hayashi
 <hayashi.kunihiko@...ionext.com>, Vinicius Costa Gomes
 <vinicius.gomes@...el.com>, intel-wired-lan@...ts.osuosl.org,
 netdev@...r.kernel.org, linux-kernel@...r.kernel.org,
 linux-stm32@...md-mailman.stormreply.com,
 linux-arm-kernel@...ts.infradead.org, bpf@...r.kernel.org
Subject: Re: [PATCH iwl-next v4 0/9] igc: Add support for Frame Preemption
 feature in IGC

On Thu Feb 13 2025, Vladimir Oltean wrote:
> So, confusingly to me, it seems like one operating mode is fundamentally
> different from the other, and something will have to change if both will
> be made to behave the same. What will change? You say mqprio will behave
> like taprio, but I think if anything, mqprio is the one which does the
> right thing, in igc_tsn_tx_arb(), and taprio seems to use the default Tx
> arbitration scheme?

Correct. taprio is using the default scheme. mqprio configures it to
what ever the user provided (in igc_tsn_tx_arb()).

> I don't think I'm on the same page as you guys, because to me, it is
> just odd that the P traffic classes would be the first ones with
> mqprio, but the last ones with taprio.

I think we are on the same page here. At the end both have to behave the
same. Either by using igc_tsn_tx_arb() for taprio too or only using the
default scheme for both (and thereby keeping broken_mqprio). Whatever
Faizal implements I'll match the behavior with mqprio.

Thanks,
Kurt

Download attachment "signature.asc" of type "application/pgp-signature" (862 bytes)