netdev - Re: [PATCH net-next v2 2/2] net: dev: introduce support for sch BYPASS for lockless qdisc

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] [day] [month] [year] [list]

Message-ID: <c9cb2979-4faa-5aa7-7f1e-5e7455c5cb10@gmail.com>
Date:   Fri, 22 Mar 2019 06:58:59 -0700
From:   Eric Dumazet <eric.dumazet@...il.com>
To:     Paolo Abeni <pabeni@...hat.com>, netdev@...r.kernel.org
Cc:     "David S. Miller" <davem@...emloft.net>,
        Eric Dumazet <edumazet@...gle.com>,
        John Fastabend <john.fastabend@...il.com>,
        Ivan Vecera <ivecera@...hat.com>
Subject: Re: [PATCH net-next v2 2/2] net: dev: introduce support for sch
 BYPASS for lockless qdisc



On 03/22/2019 01:30 AM, Paolo Abeni wrote:
> With commit c5ad119fb6c0 ("net: sched: pfifo_fast use skb_array")
> pfifo_fast no longer benefit from the TCQ_F_CAN_BYPASS optimization.
> Due to retpolines the cost of the enqueue()/dequeue() pair has become
> relevant and we observe measurable regression for the uncontended
> scenario when the packet-rate is below line rate.

Reviewed-by: Eric Dumazet <edumazet@...gle.com>