From: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
To: Dan Williams <dan.j.williams@intel.com>, vishal.l.verma@intel.com
Cc: linux-nvdimm@lists.01.org
Subject: Re: Picking 0th namespace if it is idle
Date: Thu, 30 May 2019 13:50:35 +0530 [thread overview]
Message-ID: <877ea85p64.fsf@linux.ibm.com> (raw)
In-Reply-To: <87a7f45qik.fsf@linux.ibm.com>
aneesh.kumar@linux.ibm.com (Aneesh Kumar K.V) writes:
> Hi Dan,
>
> With the patch series to mark the namespace disabled if we have mismatch
> in pfn superblock, we can endup with namespace0 marked idle/disabled.
>
> I am wondering why do do the below in ndctl.
>
>
> static struct ndctl_namespace *region_get_namespace(struct ndctl_region *region)
> {
> struct ndctl_namespace *ndns;
>
> /* prefer the 0th namespace if it is idle */
> ndctl_namespace_foreach(region, ndns)
> if (ndctl_namespace_get_id(ndns) == 0
> && !is_namespace_active(ndns))
> return ndns;
> return ndctl_region_get_namespace_seed(region);
> }
>
> I have a kernel patch that will create a namespace_seed even if we fail
> to ename a pfn backing device. Something like below
>
> @@ -747,12 +752,23 @@ static void nd_region_notify_driver_action(struct nvdimm_bus *nvdimm_bus,
> }
> }
> if (dev->parent && is_nd_region(dev->parent) && probe) {
> nd_region = to_nd_region(dev->parent);
> nvdimm_bus_lock(dev);
> if (nd_region->ns_seed == dev)
> nd_region_create_ns_seed(nd_region);
> nvdimm_bus_unlock(dev);
> }
> +
> + if (dev->parent && is_nd_region(dev->parent) && !probe && (ret == -EOPNOTSUPP)) {
> + nd_region = to_nd_region(dev->parent);
> + nvdimm_bus_lock(dev);
> + if (nd_region->ns_seed == dev)
> + nd_region_create_ns_seed(nd_region);
> + nvdimm_bus_unlock(dev);
> + }
> +
>
> With that we can end up with something like the below after boot.
> :/sys/bus/nd/devices/region0$ sudo ndctl list -Ni
> [
> {
> "dev":"namespace0.1",
> "mode":"fsdax",
> "map":"mem",
> "size":0,
> "uuid":"00000000-0000-0000-0000-000000000000",
> "state":"disabled"
> },
> {
> "dev":"namespace0.0",
> "mode":"fsdax",
> "map":"mem",
> "size":2147483648,
> "uuid":"094e703b-4bf8-4078-ad42-50bebc03e538",
> "state":"disabled"
> }
> ]
>
> namespace0.0 is the one we failed to initialize due to PAGE_SIZE
> mismatch.
>
> We do have namespace_seed pointing to namespacece0.1 correct. But a ndtl
> create-namespace will pick namespace0.0 even if we have seed file
> pointing to namespacec0.1.
>
>
> I am trying to resolve the issues related to creation of new namespaces
> when we have some namespace marked disabled due to pfn_sb setting
> mismatch.
>
> -aneesh
With that ndctl namespace0.0 selection commented out, we do get pick the
right idle namespace.
#ndctl list -Ni
[
{
"dev":"namespace0.1",
"mode":"fsdax",
"map":"mem",
"size":0,
"uuid":"00000000-0000-0000-0000-000000000000",
"state":"disabled"
},
{
"dev":"namespace0.0",
"mode":"fsdax",
"map":"mem",
"size":2147483648,
"uuid":"0c31ae4b-b053-43c7-82ff-88574e2585b0",
"state":"disabled"
}
]
after ndctl create-namespace -s 2G -r region0
# ndctl list -Ni
[
{
"dev":"namespace0.2",
"mode":"fsdax",
"map":"mem",
"size":0,
"uuid":"00000000-0000-0000-0000-000000000000",
"state":"disabled"
},
{
"dev":"namespace0.1",
"mode":"fsdax",
"map":"dev",
"size":2130706432,
"uuid":"60970059-9412-4eeb-9e7a-b314585a4da3",
"align":65536,
"blockdev":"pmem0.1",
"supported_alignments":[
65536
]
},
{
"dev":"namespace0.0",
"mode":"fsdax",
"map":"mem",
"size":2147483648,
"uuid":"0c31ae4b-b053-43c7-82ff-88574e2585b0",
"state":"disabled"
}
]
_______________________________________________
Linux-nvdimm mailing list
Linux-nvdimm@lists.01.org
https://lists.01.org/mailman/listinfo/linux-nvdimm
next parent reply other threads:[~2019-05-30 8:20 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <87a7f45qik.fsf@linux.ibm.com>
2019-05-30 8:20 ` Aneesh Kumar K.V [this message]
2019-07-23 15:00 ` Picking 0th namespace if it is idle Aneesh Kumar K.V
2019-07-23 18:59 ` Dan Williams
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=877ea85p64.fsf@linux.ibm.com \
--to=aneesh.kumar@linux.ibm.com \
--cc=dan.j.williams@intel.com \
--cc=linux-nvdimm@lists.01.org \
--cc=vishal.l.verma@intel.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox