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Subject: Re: [PATCH v2 0/6] kernfs: proposed locking and concurrency
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To:     Tejun Heo <tj@kernel.org>, Ian Kent <raven@themaw.net>
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Stephen Rothwell <sfr@canb.auug.org.au>,
        Andrew Morton <akpm@linux-foundation.org>,
        Al Viro <viro@zeniv.linux.org.uk>,
        David Howells <dhowells@redhat.com>,
        Miklos Szeredi <miklos@szeredi.hu>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        Kernel Mailing List <linux-kernel@vger.kernel.org>
References: <159237905950.89469.6559073274338175600.stgit@mickey.themaw.net>
 <20200619153833.GA5749@mtj.thefacebook.com>
From:   Rick Lindsley <ricklind@linux.vnet.ibm.com>
Message-ID: <16d9d5aa-a996-d41d-cbff-9a5937863893@linux.vnet.ibm.com>
Date:   Fri, 19 Jun 2020 13:41:39 -0700
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On 6/19/20 8:38 AM, Tejun Heo wrote:

> I don't have strong objections to the series but the rationales don't seem
> particularly strong. It's solving a suspected problem but only half way. It
> isn't clear whether this can be the long term solution for the problem
> machine and whether it will benefit anyone else in a meaningful way either.

I don't understand your statement about solving the problem halfway.  Could you elaborate?

> I think Greg already asked this but how are the 100,000+ memory objects
> used? Is that justified in the first place?

They are used for hotplugging and partitioning memory.  The size of the segments (and thus the number of them) is dictated by the underlying hardware.

Rick