From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 87F1445C6EB; Mon, 24 Aug 2026 16:32:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.133 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787589147; cv=none; b=gCn39pOdeDulmoAuVnkt7P8w8WO920q7kbBV/r+1Xz8YDd/W4K0u0q3s3W3VcBSsr4zp+cT1a+EFMoLgDL2N2hOlqMg3LjtUPnQLdAZyHLX5XITqDusH6tx7cVolGaZtit4myg9Wgz2i29hLuttBA9yc/Ud+olHr9+5hqY4b02g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787589147; c=relaxed/simple; bh=tmVJnM8+0WqjT9ypuV7jDrEJkQVA3+ITw4n1AM+P43I=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=qsE36rtFm6i36OWI4QNMlF4LQjcpBTI3aIOJcJUFpKS7M+MykTA+JpYiUyiXR79ZNz8AiXzh0gKwGBtL28FtTOttjG8+/uMsatPWDoZ0OcV4AJe90jFD9Eamyq0BhpW/bm73ZwfiwXqKprSS5KQj2wOs6MsNLi6UMdb4j1S78Sc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org; spf=pass smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=Yt9ReXi+; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="Yt9ReXi+" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Sender:Reply-To:Content-ID:Content-Description; bh=I2GLkaWfUPmegFPxXgQ548ekGVdoYEwro087l+1Nqkk=; b=Yt9ReXi+RwRKSrIuVc5G1aF8NA vxFI6hsHltULBCQGJyDBSC87k9JtrZdFoEmkvUmPTUzO1V8mKVcrmXtfywm4bjFgtST9uSAQXepi1 AuS9BL4dFPsGsT66YpOAkBUtFjGK+P3/KcpcDalk47dP7MWT0aBMffcnV5SwrjNOGTxz6JhPGhVeG CH6aNQnkfVOIdRPEKKzohvuuJ47N1jYVhlDIMyfRsku+/RvhQQK8jtMpXCvOTbqCd5PeMFL2omUa2 /8EbtaxR0f/+9KmBdrIJ2znLwN209PMdmDQritDVRJvHEjcbzsrueEBRak3fJRuuW2z/NjMOPfhJf GaHc+kYQ==; Received: from [50.53.43.113] (helo=[192.168.254.34]) by bombadil.infradead.org with esmtpsa (Exim 4.99.1 #2 (Red Hat Linux)) id 1wyXau-0000000H3Ff-148G; Mon, 24 Aug 2026 16:32:20 +0000 Message-ID: Date: Mon, 24 Aug 2026 09:32:18 -0700 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 4/5] net: Divert socket allocations to SWIOTLB for nocopy TX To: Luigi Rizzo , Marek Szyprowski , Robin Murphy , Willem de Bruijn , Kuniyuki Iwashima , "David S . Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Luigi Rizzo Cc: Greg Kroah-Hartman , Dragos Tatulea , "Rafael J . Wysocki" , Andrew Morton , David Hildenbrand , netdev@vger.kernel.org, linux-mm@kvack.org, iommu@lists.linux.dev, driver-core@lists.linux.dev, linux-kernel@vger.kernel.org References: <20260615234220.3946885-1-lrizzo@google.com> <20260824152932.1583506-1-lrizzo@google.com> <20260824152932.1583506-5-lrizzo@google.com> Content-Language: en-US From: Randy Dunlap In-Reply-To: <20260824152932.1583506-5-lrizzo@google.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 8/24/26 8:29 AM, Luigi Rizzo wrote: > diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c > index d4a07a7c570e1..7b818a796ff96 100644 > --- a/kernel/dma/swiotlb.c > +++ b/kernel/dma/swiotlb.c > @@ -63,6 +63,11 @@ > */ > #define IO_TLB_MIN_SLABS ((1<<20) >> IO_TLB_SHIFT) > > +/* enable nocopy tx swiotlb and set the percentage of buffers allowed for it. */ > +unsigned int nocopy_tx_percent; > +module_param(nocopy_tx_percent, uint, 0644); > +MODULE_PARM_DESC(nocopy_tx_percent, "percentage of swiotlb buffer allowed for nocopy tx"); Please add this module param to the existing swiotlb param documentation in Documentation/admin-guide/kernel-parameters.txt. -- ~Randy