From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ed1-f41.google.com (mail-ed1-f41.google.com [209.85.208.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1656D70 for ; Fri, 4 Jun 2021 19:34:55 +0000 (UTC) Received: by mail-ed1-f41.google.com with SMTP id f5so7394096eds.0 for ; Fri, 04 Jun 2021 12:34:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tessares-net.20150623.gappssmtp.com; s=20150623; h=subject:to:references:cc:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=hstRiTMj7tzRn2qay7CXUHvg7gQqMhhnQtWo0eDvNFI=; b=fguaH+8lBsdk+MhQ/92SbvGjHwbn1qbMK3tSf7W0HhkwmOE/K3OSj2trcgnzr/4AaU GyQtnKvKQPtXKeqpNTOwotRvYU6FBUf27dqGnaAoUtBK3k5yFVxPP3XGFGp+oMOBvXiZ 0GCBb/QuFp+THwULckgKoibdoWuMyKtS/QkoJdBn13TjbaD1xZp3Qt9lNYmahzh6S5G8 kQ39L3kXCD3Xdzt4hS7bJnzDIlL3JQH5Zu9wFLICCZjYIe9EjAVw3Tr5jy2ihRSrq9Ru D0yy8NxMX1bne4M8GJlRFcMTX43QLK/tFf1OV4ZldyDQCFj6YoLfzJIF/OBkMjz1FDcv 6npg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:cc:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=hstRiTMj7tzRn2qay7CXUHvg7gQqMhhnQtWo0eDvNFI=; b=csYBDs3GvOtPL+NEaz5vdnRADnEsi9IYbRMRVHwqkPOnlkw6MD1NkfGKx1mHw92/zV P0u3zu3VrzcXbX2muI2JZFf1rgIQ5bAVetVJcx3f7teIlMmY0SpuroOR4S5OnlK4vAJn uOFhRlNDC2/QocBteQeV0gSg3NYtW4ATDRfN8RGMY9G36D5QpGwvE+FFU+1QUav5QkW4 30sSYivZrXnCDLsifkqJwERRg9EXEt8/+QTSIsrQt+fIS85v4g3CU6vhCR6OhPqXgX3Y 0/90U15FGEHtPdv9RIvycDhV6oKmszVZBqCFzjBCOU464z1OL+Nc6MWjiJjUpBlkXGkw egLQ== X-Gm-Message-State: AOAM531bdUlAfoJR0JA+PRSxWP5fQYa2RgDivoG/lbw7n8929QabjpSK kSgvqfL8zLN0uoIFfS6BVDAISJKzqaQbBLGF X-Google-Smtp-Source: ABdhPJxS5/xnFnaJzeQZQf7BZ0AWfiF+C2Et3GJ9JZuSmirb/Sg1BkWm2aDfTe78mziOwy/Gx8X8kA== X-Received: by 2002:aa7:d85a:: with SMTP id f26mr6352271eds.332.1622835294034; Fri, 04 Jun 2021 12:34:54 -0700 (PDT) Received: from tsr-lap-08.nix.tessares.net ([2a02:578:85b0:e00:c047:d46c:d45:3868]) by smtp.gmail.com with ESMTPSA id f3sm3696443eds.59.2021.06.04.12.34.53 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 04 Jun 2021 12:34:53 -0700 (PDT) Subject: Re: [PATCH mptcp-net] mptcp: try harder to borrow memory from subflow under pressure To: Paolo Abeni , Mat Martineau References: Cc: mptcp@lists.linux.dev From: Matthieu Baerts Message-ID: <260c6ca2-014c-a1c9-696b-ec2293f8d02f@tessares.net> Date: Fri, 4 Jun 2021 21:34:53 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.8.1 X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-GB Content-Transfer-Encoding: 7bit Hi Paolo, Mat, On 26/05/2021 18:10, Paolo Abeni wrote: > If the host is under sever memory pressure, and RX forward > memory allocation for the msk fails, we try to borrow the > required memory from the ingress subflow. > > The current attempt is a bit flaky: if skb->truesize is less > than SK_MEM_QUANTUM, the ssk will not release any memory, and > the next schedule will fail again. > > Instead, directly move the required amount of pages from the > ssk to the msk, if available > > Fixes: 9c3f94e1681b ("mptcp: add missing memory scheduling in the rx path") > Signed-off-by: Paolo Abeni Thank you for the patch and the review! (and sorry for the delay) - fa92849db4ec: mptcp: try harder to borrow memory from subflow under pressure - Results: 809268f427a5..119541ecd3c9 Builds and tests are now in progress: https://cirrus-ci.com/github/multipath-tcp/mptcp_net-next/export/20210604T193342 https://github.com/multipath-tcp/mptcp_net-next/actions/workflows/build-validation.yml?query=branch:export/20210604T193342 Cheers, Matt -- Tessares | Belgium | Hybrid Access Solutions www.tessares.net