From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 54858C4361B for ; Thu, 17 Dec 2020 13:02:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E48482389E for ; Thu, 17 Dec 2020 13:02:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726569AbgLQNCh (ORCPT ); Thu, 17 Dec 2020 08:02:37 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:48929 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725468AbgLQNCf (ORCPT ); Thu, 17 Dec 2020 08:02:35 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1608210069; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=3btdC8Ib+nc1YRjIp7Bv/qq+C1KrupIw6hpcJ5w7MKs=; b=e5WTZc/M/uwYAFgXlCrsYogJ9F9QtIM4lVCi8EuTxwjOqhVmV1aKQsNNEf/m92isATwTDa SplHQUhQvJjNIXk1HtgshpdiLdjijZM4AKG7b+jYbInHze0pr828t/hzvX10K5+3n8PwgA BrveuqNnc+TLVFbR2EugGb2G7/SN3Uc= Received: from mail-wm1-f70.google.com (mail-wm1-f70.google.com [209.85.128.70]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-234-OxbfjTm5PaiLtA9XoDayFg-1; Thu, 17 Dec 2020 08:01:08 -0500 X-MC-Unique: OxbfjTm5PaiLtA9XoDayFg-1 Received: by mail-wm1-f70.google.com with SMTP id a205so1529601wme.9 for ; Thu, 17 Dec 2020 05:01:06 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:in-reply-to:references:date :message-id:mime-version:content-transfer-encoding; bh=3btdC8Ib+nc1YRjIp7Bv/qq+C1KrupIw6hpcJ5w7MKs=; b=GbZt/9OZt8yuJ4kSz5OQrFrWOuu5dzRb2Dl4FyOKxxmrYAiT80zUoj/QRhUi+y0DRe Uu+Ud5cy8AcEU+0kFrDbMcmICMDw300UHczVui1Hpl0scja2juunURlAf+Rfk5611GJJ mZwXo6IE2wQ8EefYkN3hPUmjqRZdr6XUL+ZDBHiYaXiOEvv1C7T1CD2rr+NWwJCQfTjZ JkpZjgljICKFkPwgGAizBE/A16WbPtmT5J2+M5h2hFN73t2yn1wa1ECQowPOBZhy9LHX +lPHWLEa9wSZzSiuQUX1xl3HWxCJS37YJQBQoMlvAkMn3tycyc1iB44XGjUpHR6owAOv 0RLA== X-Gm-Message-State: AOAM5322SE11PzdrtNWANnedgaiTqRu31NRv6JTU2gX1swiuhiJeyyoI RRQ/KDcew7hs98SYMdpHXLn9o85YvbqD2z/k3luYZVLE4KfnAZoBKd9d4R8y/ReKg6hF+HbNHc7 St5H3f3Gdu4OFtxIAX43Reph450Q= X-Received: by 2002:a5d:540f:: with SMTP id g15mr43756745wrv.397.1608210065407; Thu, 17 Dec 2020 05:01:05 -0800 (PST) X-Google-Smtp-Source: ABdhPJzmxy4s1F7mQbMJr0K6WoCAqlpLJHcHz1wMQecQOUJ/UygWggAzxtKYDeRP7a2ZdZczRlYN6A== X-Received: by 2002:a5d:540f:: with SMTP id g15mr43756715wrv.397.1608210065175; Thu, 17 Dec 2020 05:01:05 -0800 (PST) Received: from alrua-x1.borgediget.toke.dk ([45.145.92.2]) by smtp.gmail.com with ESMTPSA id t13sm9215188wrs.26.2020.12.17.05.01.04 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 17 Dec 2020 05:01:04 -0800 (PST) Received: by alrua-x1.borgediget.toke.dk (Postfix, from userid 1000) id 3F6001802A7; Thu, 17 Dec 2020 14:01:03 +0100 (CET) From: Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= To: Felix Fietkau , linux-wireless@vger.kernel.org Cc: johannes@sipsolutions.net Subject: Re: [PATCH 2/7] mac80211: force calculation of software hash for tx fair queueing In-Reply-To: References: <20201216204316.44498-1-nbd@nbd.name> <20201216204316.44498-2-nbd@nbd.name> <87czz8bqbj.fsf@toke.dk> X-Clacks-Overhead: GNU Terry Pratchett Date: Thu, 17 Dec 2020 14:01:03 +0100 Message-ID: <871rfobn8w.fsf@toke.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org Felix Fietkau writes: > On 2020-12-17 12:54, Toke H=C3=B8iland-J=C3=B8rgensen wrote: >> Felix Fietkau writes: >>=20 >>> Depending on the source, a hardware calculated hash may not provide the >>> same level of collision resistance. >>=20 >> This seems like it would have performance implications? >>=20 >> Also, this can potentially discard information from tunnels that >> preserve the hash before encapsulation (we added support for this to >> Wireguard which had some nice effects on queueing of encapsulated >> traffic). > If the hash was calculated in software using the flow dissector, it will > be preserved, even if it went through a few virtual interfaces. > The only hashes discarded are hardware generated ones. Yeah, but I was thinking something like: Packet comes in with HW hash -> gets encapsulated (preserving the hash) -> gets to mac80211 which discards the HW hash. So now you're replacing a (possibly bad-quality) HW hash with a software hash of the *outer* encapsulation header... -Toke