From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jens Axboe Subject: Re: async network I/O, event channels, etc Date: Thu, 27 Jul 2006 10:29:24 +0200 Message-ID: <20060727082924.GK5282@suse.de> References: <20060727.010255.87351515.davem@davemloft.net> <20060727080901.GG5282@suse.de> <20060727081114.GH5282@suse.de> <20060727.012037.78156999.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: johnpol@2ka.mipt.ru, drepper@redhat.com, linux-kernel@vger.kernel.org, netdev@vger.kernel.org Return-path: To: David Miller Content-Disposition: inline In-Reply-To: <20060727.012037.78156999.davem@davemloft.net> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Thu, Jul 27 2006, David Miller wrote: > From: Jens Axboe > Date: Thu, 27 Jul 2006 10:11:15 +0200 > > > Ownership transition from user -> kernel that is, what I'm trying to say > > that returning ownership to the user again is the tricky part. > > Yes, it is important that for TCP, for example, we don't give > the user the event until the data is acknowledged and the skb's > referencing that data are fully freed. > > This is further complicated by the fact that packetization boundaries > are going to be different from AIO buffer boundaries. > > I think this is what you are alluding to. Precisely. And this is the bit that is currently still broken for splice-to-socket, since it gives that ack right after ->sendpage() has been called. But that's a known deficiency right now, I think Alexey is currently looking at that (as well as receive side support). -- Jens Axboe