From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arne Jansen Subject: Re: [RFC] Tree fragmentation and prefetching Date: Fri, 25 Mar 2011 21:14:35 +0100 Message-ID: <4D8CF7AB.4010102@gmx.net> References: <4D89F03A.9050306@gmx.net> <1300908672-sup-9552@think> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Cc: Linux Btrfs To: Chris Mason Return-path: In-Reply-To: <1300908672-sup-9552@think> List-ID: On 23.03.2011 20:32, Chris Mason wrote: > Excerpts from Arne Jansen's message of 2011-03-23 09:06:02 -0400: >> >> For the implementation I'd need an interface which I haven't been able >> to find yet. Currently I can trigger the read of several pages / tree >> blocks and wait for the completion of each of them. What I'd need would >> be an interface that gives me a callback on each completion or a waiting >> function that wakes up on each completion with the information which >> pages just completed. >> One way to achieve this would be to add a hook, but I gladly take any >> implementation hints. > > We have the bio endio call backs for this, I think that's the only thing > you can use. > ok, so I'll add a new extent state bit EXTENT_READAHEAD and test for it in btree_readpage_end_io_hook.