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Date:   Fri, 27 Dec 2019 11:36:56 +0000
From:   Chris Down <chris@chrisdown.name>
To:     Amir Goldstein <amir73il@gmail.com>
Cc:     linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Matthew Wilcox <willy@infradead.org>,
        Jeff Layton <jlayton@kernel.org>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Tejun Heo <tj@kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>, kernel-team@fb.com,
        "zhengbin (A)" <zhengbin13@huawei.com>
Subject: Re: [PATCH] fs: inode: Recycle inodenum from volatile inode slabs
Message-ID: <20191227113656.GA442424@chrisdown.name>
References: <20191226154808.GA418948@chrisdown.name>
 <CAOQ4uxj8NVwrCTswut+icF2t1-7gtW_cmyuGO7WUWdNZLHOBYA@mail.gmail.com>
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Amir Goldstein writes:
>> - bpffs
>> - configfs
>> - debugfs
>> - efivarfs
>> - hugetlbfs
>> - ramfs
>> - tmpfs
>>
>
>I'm confused about this list.
>I suggested to convert tmpfs and hugetlbfs because they use a private
>inode cache pool, therefore, you can know for sure that a recycled i_ino
>was allocated by get_next_ino().

Oh, right. I mistakenly thought alloc_inode was somehow sb-specific and missed 
that these don't have any super_operations->alloc_inode :-)

I'll reduce it just to those with this explicitly set.

>I'd go even further to say that introducing a generic helper for this sort
>of thing is asking for trouble. It is best to keep the recycle logic well within
>the bounds of the specific filesystem driver, which is the owner of the
>private inode cache and the responsible for allocating ino numbers in
>this pool.

Thanks, considering that alloc_inode isn't sb-dependent like I thought, that 
definitely sounds reasonable. I'll do that and send v3 then.

Thanks,

Chris