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Date:   Mon, 27 Nov 2023 03:44:11 -0700
From:   Keith Busch <kbusch@kernel.org>
To:     Daniel Wagner <dwagner@suse.de>
Cc:     linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org,
        Christoph Hellwig <hch@lst.de>,
        Sagi Grimberg <sagi@grimberg.me>,
        Hannes Reinecke <hare@suse.de>
Subject: Re: [RFC v1] nvme: add cse, ds, ms, nsze and nuse to sysfs
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References: <20231127103208.25748-1-dwagner@suse.de>
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On Mon, Nov 27, 2023 at 11:32:08AM +0100, Daniel Wagner wrote:
> libnvme is using the sysfs for enumarating the nvme resources. Though
> there are few missing attritbutes in the sysfs. For these libnvme issues
> commands during discovering.
> 
> As the kernel already knows all these attributes and we would like to
> avoid libnvme to issue commands all the time, expose these missing
> attributes.

The id namespace 'nuse' field can be quite volatile: it can change on
any write or discard command, so caching it may quickly get out of sync
with the actual value.