From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7A55B322B8F for ; Thu, 6 Aug 2026 16:45:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786034736; cv=none; b=LWp0lTGHN0tMeHdwlNtulV9Zw5nuZPwDuKnQaVTHmR2Fzs2qVBo35izuCbqj43AjqwD3JaPOmKy6LxON0sxN8LlRPA6lPh0dmsqibe7rKlbO/M5bc5RunShxNXpXSFatESfB1bSZyzwW/kMvUgBQvzPMCQt1s1eBBDY1/tWjBMw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786034736; c=relaxed/simple; bh=2JTgvZXMbRn/gU4GMjtfRyQvsG3iH2cQv8BfnoMcYHM=; h=Message-ID:Date:MIME-Version:Subject:To:References:From: In-Reply-To:Content-Type; b=SLKBXZarn3/TdBlIKAO5+0KQ/i0YTJ+tQ5r4HUs8vzVkiQxfD3EWgAnp3chxespjdM9rDC6Y9WOZPxkJuiXO0gWQINOmlbCSXpNd4+aajM+cNd69nWMpjOM5DyjL99jv+SAebCIkk/PHoVeK1UXKjDZqBdU5DaV65ow2sHVIjOw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=WC4Wn4g4; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="WC4Wn4g4" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 842681F000E9; Thu, 6 Aug 2026 16:45:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1786034733; bh=bVbO4oMQPULoUIk6vgf/rtOXtQn1kRQuXnrPqMC+sjQ=; h=Date:Subject:To:References:From:In-Reply-To; b=WC4Wn4g47hJfPvukltE/+qLBi/Joaj7iK+A6gDZqKDVhNYrMCdou2tKXTj6Z0CyRC GUs8xyIlPUZ+STgn91UF7+GGkF01xNf4ul/uYS4yWPL4RCGTjPwcdi/EANrYkAOw4e X7bXnZB2gLaSbXIFFDmfqmggDvcACIYyAmJWPrG4Zl4MdlFb9h2RlpHfo9bE/YoJui tR8qIqEXa1wamM97SZ+5ED3nfii1XJ57Ed98cliC7IKOFOH5YgvAVGLm0Hies1/IGW /brktR1z8qsevs4AQUmczLNTZAy3tB4HhepFGGgNCpQiCieDUaOI8LEwGcX16r+RK6 joUaskT+WO7Lw== Message-ID: Date: Thu, 6 Aug 2026 18:45:30 +0200 Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Beta Subject: Re: [PATCH v2 mptcp-next 2/7] mptcp: move the stale logic out of retrans scheduler Content-Language: fr To: Paolo Abeni , mptcp@lists.linux.dev References: <0a81a4bf60008faefdd1688012b8fcebc291a4d6.1786026372.git.pabeni@redhat.com> From: Matthieu Baerts Autocrypt: addr=matttbe@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 06/08/2026 18:41, Paolo Abeni wrote: > On 8/6/26 4:45 PM, Paolo Abeni wrote: >> This allow separating the stale logic invocation and the retrans >> scheduler, and will simplify the next patch. >> >> It's also a cleaner design as the retrans scheduler has currently >> too many side effects. As a possible downside, the retrans work will >> now traverse the subflows list additional times; that does not matter >> much, as this is slowpath. >> >> While at it, pick more accurate names for the involved helpers and >> explicitly note that the per subflow stale data is under msk socket >> lock protection. >> >> The scheduler and the stale logic may observe different subflow >> statues, as no subflow lock is acquired. This is intentional and not >> harmful, worst case leading to slower retransmissions. >> >> Signed-off-by: Paolo Abeni >> --- >> v1 -> v2: >> - fix stale lockless access >> >> Note: BPF scheduler should be rebase to use the renamed helper > Additional note: I think the rename is a good thing, because the > function additionally changed the argument list. Fine by me: these helpers are only in our export branch anyway. > @Mat: please LMK if you are ok with squash-to patches for later > self-tests/bpf things to be adjusted. Yes, of course. Because they are now our of the scheduler API, I guess they can be removed. So Geliang's series can be used on top of yours: https://lore.kernel.org/cover.1786007209.git.tanggeliang@kylinos.cn Cheers, Matt -- Sponsored by the NGI0 Core fund.