Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751842AbbFZAzr (ORCPT ); Thu, 25 Jun 2015 20:55:47 -0400 Received: from g4t3426.houston.hp.com ([15.201.208.54]:42510 "EHLO g4t3426.houston.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750792AbbFZAzj (ORCPT ); Thu, 25 Jun 2015 20:55:39 -0400 Message-ID: <1435280115.11808.374.camel@misato.fc.hp.com> Subject: Re: [PATCH v2 15/17] libnvdimm: Set numa_node to NVDIMM devices From: Toshi Kani To: "Williams, Dan J" Cc: "mingo@kernel.org" , "linux-kernel@vger.kernel.org" , "linux-nvdimm@lists.01.org" , "hch@lst.de" , "linux-acpi@vger.kernel.org" , "axboe@kernel.dk" , "linux-fsdevel@vger.kernel.org" Date: Thu, 25 Jun 2015 18:55:15 -0600 In-Reply-To: <1435275750.18090.5.camel@intel.com> References: <20150625090554.40066.69562.stgit@dwillia2-desk3.jf.intel.com> <20150625093738.40066.88750.stgit@dwillia2-desk3.jf.intel.com> <1435254317.11808.327.camel@misato.fc.hp.com> <1435257283.13411.4.camel@intel.com> <1435269103.11808.349.camel@misato.fc.hp.com> <1435270287.11808.352.camel@misato.fc.hp.com> <1435272910.11808.356.camel@misato.fc.hp.com> <1435275750.18090.5.camel@intel.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.10.4 (3.10.4-4.fc20) Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3581 Lines: 92 On Thu, 2015-06-25 at 23:42 +0000, Williams, Dan J wrote: > On Thu, 2015-06-25 at 16:55 -0600, Toshi Kani wrote: > > On Thu, 2015-06-25 at 15:34 -0700, Dan Williams wrote: > > > On Thu, Jun 25, 2015 at 3:11 PM, Toshi Kani wrote: > > > > On Thu, 2015-06-25 at 15:00 -0700, Dan Williams wrote: > > > > Yes, I see no problem with bound BTTs and their device files. So, how > > > > do we bind BTT with this new version? > > > > > > > > > > # cd /sys/bus/nd/devices > > > # uuidgen > btt6/uuid > > > # echo 4096 > btt6/sector_size > > > # echo namespace6.0 > btt6/namespace > > > # echo namespace6.0 > ../drivers/nd_pmem/unbind > > > # echo btt6 > ../drivers/nd_pmem/bind > > > > > > After reboot, when the system sees namespace6.0 again it will notice > > > the btt instance and attach bttX instead. The net effect is that now > > > you'll only ever have /dev/pmem6 or /dev/pmem6s, never both at the > > > same time that was a side effect of the stacking approach. > > > > > > I'll post the patch that updates libndctl and the unit tests shortly > > > > Maybe I am missing something, but I am getting errors on my system. (I > > used btt0 since there is no btt6.) > > > > # cat bind.sh > > set -x > > cd /sys/bus/nd/devices > > uuidgen > btt0/uuid > > echo 4096 > btt0/sector_size > > echo namespace0.0 > btt0/namespace > > echo namespace0.0 > ../drivers/nd_pmem/unbind > > echo btt0 > ../drivers/nd_pmem/bind > > > > # sh bind.sh > > + cd /sys/bus/nd/devices > > + uuidgen > > + echo 4096 > > + echo namespace0.0 > > bind.sh: line 6: echo: write error: Device or resource busy > > + echo namespace0.0 > > bind.sh: line 7: echo: write error: No such device > > + echo btt0 > > bind.sh: line 8: echo: write error: No such device > > > > # dmesg > > : > > [12513.839162] nd btt0: uuid_store: result: 0 wrote: > > b32cd195-9aae-4c54-a5ac-49adb50a8a98 > > [12513.880286] nd btt0: sector_size_store: result: 0 wrote: 4096 > > [12513.909494] nd btt0: namespace0.0 already claimed > > [12513.933364] nd btt0: namespace_store: result: -16 wrote: namespace0.0 > > [12513.966808] ndbus0: nd_pmem.probe(btt0) = -19 > > > > So this turned out to be a perfect example of why we might want to have > the region-id in the btt device name just like namespaces, because btt0 > was actually bound to namespace4.0 on Toshi's system. The following > update, that I will fold in to the series, fixes this. Note that the > association of btt id to to namespace is still non-deterministic. I.e. > btt0.1 could be assigned as the btt for namespace0.0, but at least when > looking at /sys/bus/nd/devices it will be clear which btts belong to > which regions. > > # ls /sys/bus/nd/devices > btt0.0 btt3.0 btt6.0 namespace2.0 namespace5.0 nmem1 nmem4 region2 region5 > btt1.0 btt4.0 namespace0.0 namespace3.0 namespace6.0 nmem2 region0 region3 region6 > btt2.0 btt5.0 namespace1.0 namespace4.0 nmem0 nmem3 region1 region4 Yes, this works nicely. :-) Now, how do I unbind BTT? I did the following as a guess, but BTT got reattached again before I have a chance to delete the metadata, which I need /dev/pmemN. NUM=1 cd /sys/bus/nd/devices echo "" > btt${NUM}.1/namespace echo btt${NUM}.1 > ../drivers/nd_pmem/unbind echo namespace${NUM}.0 > ../drivers/nd_pmem/bind Thanks, -Toshi -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/