From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 CDD7415250C; Tue, 4 Jun 2024 14:42:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717512146; cv=none; b=bxnJLQ+FpAdnidIFjLIlZ/QXsvCCBCQ2cBc/e8NhsgLOCC1r8EwUY6yDRrz3fJ7lRLqzv88SONpVKjHHJVgyL7o5iLVw4/heXKQ/ZQZ82Vdg13zb7+aa2B5mmiK0CfdhuzkmIkNrNaiCBaotFgAIpDACvecwF8fdKWUiAvSTmLM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717512146; c=relaxed/simple; bh=fmlRiz5M5NjXBFuEtUQcEwmSqlNPoKCDWdQmvJU2bn8=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=BFef4EKPFv3FJj/mi6+HxkutsUkVsXBVDPB36bkM00VUWnrRtziUIvpK7zJGSI7An7n8IQWn7EaawKzAnGbwbTrMmNfVepplW0RbEw5ZDmpoqlZ90MTfYWEnms+0aT/D05VutT29oOR73/6HzbvSx+syr1DCLtJ+f5sRmNyxciM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=n4L/sFM8; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="n4L/sFM8" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9731AC32786; Tue, 4 Jun 2024 14:42:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1717512146; bh=fmlRiz5M5NjXBFuEtUQcEwmSqlNPoKCDWdQmvJU2bn8=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=n4L/sFM8i0oFnDH7F8EaDAMFQuuQh8PoG7QQq1M8IxZeajDv8ixPlzS8RP5O5WSbo fx1EtGxLjwFmVcfA7L6XJ9nj159hlyDZMc5x3Rop05fJhMF0pnorbMylNaXque9krv nRofPSsBjJTBD+bxZ5P7AhVAicmfaTkOKshWmMLUxvyDRcPKU89n/WuKiFwbnGnmhg 7nCXXoiTqNiZjM8rwLtJ/ZsklEk4PWnKZZJZr8AwL96O1R3jn01o0gIHPfx3nzAUpc gjuPAWdnyLbyguqM/uXLIwcHdQYnVguuAoMNTsqVxMHwDWIVHTh0ulOUvJoNsydamC Bk9alCkb/mfng== Date: Tue, 4 Jun 2024 07:42:24 -0700 From: Jakub Kicinski To: Christoph Hellwig Cc: Ofir Gal , davem@davemloft.net, linux-block@vger.kernel.org, linux-nvme@lists.infradead.org, netdev@vger.kernel.org, ceph-devel@vger.kernel.org, dhowells@redhat.com, edumazet@google.com, pabeni@redhat.com, kbusch@kernel.org, axboe@kernel.dk, sagi@grimberg.me, philipp.reisner@linbit.com, lars.ellenberg@linbit.com, christoph.boehmwalder@linbit.com, idryomov@gmail.com, xiubli@redhat.com Subject: Re: [PATCH v2 0/4] bugfix: Introduce sendpages_ok() to check sendpage_ok() on contiguous pages Message-ID: <20240604074224.44668dab@kernel.org> In-Reply-To: <20240604043041.GA28886@lst.de> References: <20240530142417.146696-1-ofir.gal@volumez.com> <20240531073214.GA19108@lst.de> <20240601153610.30a92740@kernel.org> <20240604043041.GA28886@lst.de> Precedence: bulk X-Mailing-List: ceph-devel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Tue, 4 Jun 2024 06:30:41 +0200 Christoph Hellwig wrote: > On Sat, Jun 01, 2024 at 03:36:10PM -0700, Jakub Kicinski wrote: > > On Fri, 31 May 2024 09:32:14 +0200 Christoph Hellwig wrote: > > > I still find it hightly annoying that we can't have a helper that > > > simply does the right thing for callers, but I guess this is the > > > best thing we can get without a change of mind from the networking > > > maintainers.. > > > > Change mind about what? Did I miss a discussion? > > Having a net helper to just send some memory in the most efficient > way and leave it up to the networking code to decide if it wants > to use sendpage or sendmsg internally as needed instead of burdening > the caller. I'd guess the thinking was that if we push back the callers would switch the relevant allocations to be page-backed. But we can add a comment above the helper that says "you'd be better off using page frags and calling sendmsg(MSG_SPLICE_PAGES) directly".