All of lore.kernel.org
 help / color / mirror / Atom feed
From: Sagi Grimberg <sagi@grimberg.me>
To: Keith Busch <kbusch@kernel.org>, Christoph Hellwig <hch@lst.de>
Cc: Anton Eidelman <anton.eidelman@gmail.com>,
	linux-nvme@lists.infradead.org, axboe@fb.com,
	Anton Eidelman <anton@lightbitslabs.com>,
	Chaitanya Kulkarni <kch@nvidia.com>
Subject: Re: [PATCH v2 3/3] nvme/multipath: fix stale ana state for namespaces just added by scan work
Date: Tue, 14 Sep 2021 09:24:30 +0300	[thread overview]
Message-ID: <520b56e9-cac4-3cd7-9d2e-16633c6e7df5@grimberg.me> (raw)
In-Reply-To: <20210913160831.GC3283786@dhcp-10-100-145-180.wdc.com>


>>> Scan work initially adds new namespaces to ctrl->namespaces TAIL.
>>> They make the list unordered temporarily until nvme_scan_work()
>>> finally sorts the list.
>>>
>>> Solution:
>>> In order to preserve the way ctrl->namespaces is updated and sorted,
>>> make nvme_update_ana_state() deal with the case where ctrl->namespaces
>>> is not fully sorted and has new namespaces appended with potentially
>>> lower nsids.
>>> nvme_update_ana_state() keeps track of the nsid seen in the list,
>>> detects the unsorted case (rare), and restarts scanning of desc->nsids.
>>
>> Can we dust off the patch from Chaitanya to switch to an always sorted
>> xarray instead of papering over this delayed sort?
> 
> Yeah, that's what I was going to say. :)

I agree it should not happen with xarray as inserts preserve sorting,
but that patch has the non-trivial removal of the namespaces_rwsem which
synchronizes in a lot in a lot of error recovery flows. It's very
possible that xarray will introduce regressions.

Anton, is it possible to rerun tests with the xarray patch applied?
The latest one is:
[PATCH V6] nvme-core: use xarray for ctrl ns tracking

_______________________________________________
Linux-nvme mailing list
Linux-nvme@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-nvme

  reply	other threads:[~2021-09-14  6:24 UTC|newest]

Thread overview: 35+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-09-12 18:54 [PATCH RESEND 0/3] nvme/mpath: fix missed namespaces in ana state update Anton Eidelman
2021-09-12 18:54 ` [PATCH 1/3] nvme/multipath: fix failure to update ns ana state Anton Eidelman
2021-09-12 18:54 ` [PATCH 2/3] nvme/multipath: cosmetic: keep ns nsid locally Anton Eidelman
2021-09-12 18:54 ` [PATCH 3/3] nvme/multipath: fix stale ana state for namespaces just added by scan work Anton Eidelman
2021-09-13 15:30   ` [PATCH v2 0/3] nvme/mpath: fix missed namespaces in ana state update Anton Eidelman
2021-09-13 15:30     ` [PATCH v2 1/3] nvme/multipath: fix failure to update ns ana state Anton Eidelman
2021-09-13 16:01       ` Christoph Hellwig
2021-09-13 19:29       ` Sagi Grimberg
2021-09-14  8:27       ` Christoph Hellwig
2021-09-13 15:30     ` [PATCH v2 2/3] nvme/multipath: cosmetic: keep ns nsid locally Anton Eidelman
2021-09-13 16:02       ` Christoph Hellwig
2021-09-13 20:19         ` Anton Eidelman
2021-09-13 20:57           ` Keith Busch
2021-09-14  5:44             ` Christoph Hellwig
2021-09-13 15:30     ` [PATCH v2 3/3] nvme/multipath: fix stale ana state for namespaces just added by scan work Anton Eidelman
2021-09-13 16:03       ` Christoph Hellwig
2021-09-13 16:08         ` Keith Busch
2021-09-14  6:24           ` Sagi Grimberg [this message]
2021-09-14  6:30             ` Christoph Hellwig
2021-09-14  6:40               ` Christoph Hellwig
2021-09-14  7:09               ` Sagi Grimberg
2021-09-14  7:32                 ` Christoph Hellwig
2021-09-14 16:45                   ` Anton Eidelman
2021-09-15  9:32                     ` Sagi Grimberg
2021-09-14 14:24               ` Keith Busch
2021-09-13 16:07       ` Keith Busch
2021-09-13 16:11         ` Christoph Hellwig
2021-09-13 16:24           ` Keith Busch
2021-09-13 16:46           ` Anton Eidelman
2021-09-13 15:32     ` [PATCH v2 0/3] nvme/mpath: fix missed namespaces in ana state update Christoph Hellwig
2021-09-13 15:42     ` [PATCH v2 0/3] nvme/mpath: fix missed namespaces in ana state update FIXED Anton Eidelman
2021-09-13 21:46       ` [PATCH v3 0/3] nvme/mpath: fix missed namespaces in ana state update Anton Eidelman
2021-09-13 21:46         ` [PATCH v3 1/3] nvme/multipath: fix failure to update ns ana state Anton Eidelman
2021-09-13 21:46         ` [PATCH v3 2/3] nvme/multipath: cosmetic: keep ns nsid locally Anton Eidelman
2021-09-13 21:46         ` [PATCH v3 3/3] nvme/multipath: fix stale ana state for namespaces just added by scan work Anton Eidelman

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=520b56e9-cac4-3cd7-9d2e-16633c6e7df5@grimberg.me \
    --to=sagi@grimberg.me \
    --cc=anton.eidelman@gmail.com \
    --cc=anton@lightbitslabs.com \
    --cc=axboe@fb.com \
    --cc=hch@lst.de \
    --cc=kbusch@kernel.org \
    --cc=kch@nvidia.com \
    --cc=linux-nvme@lists.infradead.org \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.