From mboxrd@z Thu Jan 1 00:00:00 1970 From: Boaz Harrosh Subject: Re: [dm-devel] REQUEST for new 'topology' metrics to be moved out of the 'queue' sysfs directory. Date: Mon, 29 Jun 2009 15:45:16 +0300 Message-ID: <4A48B75C.5080209@panasas.com> References: <125b48b7ffc99a496fbdd512f38cada5.squirrel@neil.brown.name> <20090625194015.GB31415@kernel.dk> <19012.49673.454853.975682@notabene.brown> <20090626125037.GO23611@kernel.dk> <20090626132940.GR23611@kernel.dk> <19014.4447.248248.63960@notabene.brown> <20090629101841.GF23611@kernel.dk> <20090629114121.GH23611@kernel.dk> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20090629114121.GH23611@kernel.dk> Sender: linux-raid-owner@vger.kernel.org To: Jens Axboe Cc: NeilBrown , "Martin K. Petersen" , Mike Snitzer , Linus Torvalds , Alasdair G Kergon , linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org, linux-ide@vger.kernel.org, linux-fsdevel@vger.kernel.org, device-mapper development List-Id: linux-ide@vger.kernel.org On 06/29/2009 02:41 PM, Jens Axboe wrote: > On Mon, Jun 29 2009, NeilBrown wrote: >> On Mon, June 29, 2009 8:18 pm, Jens Axboe wrote: >>> On Sat, Jun 27 2009, Neil Brown wrote: >>>>> There's no such thing as first or second class block devices. The fact >>>>> that drivers using ->make_request_fn directly do not utilize the full >>>>> scope of the queue isn't a very interesting fact, imho. >>>> Your phrase "drivers using ->make_request_fn directly" seems to >>>> suggest you are looking at things very differently to me. >>>> >>>> From my perspective, all drivers use ->make_request_fn equally. >>>> Some set it to "__make_request", some to "md_make_request", others to >>>> "dm_request" or "loop_make_request" etc. >>> Neil, will you please stop these silly games. Stop trying to invent >>> differences based on interpretations of what you read into my replies. >> >> We do seem to be having trouble communicating don't we :-( >> Be assured that it is not my intention to play games, silly or otherwise. >> >> Maybe I should just try sending you patches. Maybe that will >> make my meaning clearer. >> >> For the moment, I'm much more interested in the other question, >> that of whether I can avoid having a 'queue' directory introduced into >> md/dm/etc device directories in sysfs. > > We already talked about this, several times. My answer is that it seems > pointless to begin with internally, and externally it just makes the API > worse since tools then have to know which device type they are talking > to. > I do however see a problem with sysfs-files that mostly work for most devices but for some "device type" they do nothing silently. At least make these directory/files read-only for the un-used cases (eg. dm/md). And return proper values to indicate their un-usefulness like "-1" or "NA" > So I still see absolutely zero point in making such a change, quite the > opposite. > Just my $0.017 Boaz