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From:   Hridya Valsaraju <hridya@google.com>
Date:   Mon, 28 Oct 2019 17:26:46 -0700
Message-ID: <CA+wgaPMcJWqwiQwt9z0+C5AFMbAB7wSuNeE9wvp3PDOYF_6kew@mail.gmail.com>
Subject: Re: [PATCH 2/2] f2fs: Add f2fs stats to sysfs
To:     Chao Yu <yuchao0@huawei.com>
Cc:     Jaegeuk Kim <jaegeuk@kernel.org>,
        linux-f2fs-devel@lists.sourceforge.net,
        LKML <linux-kernel@vger.kernel.org>,
        Android Kernel Team <kernel-team@android.com>
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On Fri, Oct 25, 2019 at 6:38 PM Chao Yu <yuchao0@huawei.com> wrote:
>
> On 2019/10/26 2:22, Jaegeuk Kim wrote:
> > On 10/25, Chao Yu wrote:
> >> On 2019/10/25 11:51, Hridya Valsaraju wrote:
> >>> On Thu, Oct 24, 2019 at 2:26 AM Chao Yu <yuchao0@huawei.com> wrote:
> >>>>
> >>>> On 2019/10/24 5:48, Hridya Valsaraju wrote:
> >>>>> Currently f2fs stats are only available from /d/f2fs/status. This patch
> >>>>> adds some of the f2fs stats to sysfs so that they are accessible even
> >>>>> when debugfs is not mounted.
> >>>>
> >>>> Why don't we mount debugfs first?
> >>>
> >>> Thank you for taking a look at the patch Chao. We will not be mounting
> >>> debugfs for security reasons.
> >>
> >> Hi, Hridya,
> >>
> >> May I ask is there any use case for those new entries?
> >>
> >> So many sysfs entries exist, if there is real use case, how about backuping
> >> entire /d/f2fs/status entry into /proc/fs/f2fs/<dev>/ directory rather than
> >> adding some of stats as a single entry in sysfs directory?
> >
> > These will be useful to keep a track on f2fs health status by one value
> > per entry, which doesn't require user-land parsing stuff. Of course, Android
> > can exploit them by IdleMaint, rollback feature, and so on.
>
> Alright, I suggest to add a sub-directory for those statistic entries, we can
> manage them more easily isolated from those existed switch entries.

Thank you Chao and Jaegeuk. I will make this change and send out a new version.

Regards,
Hridya

>
> Thanks,
>
> >
> >>
> >> Thanks,
> >>
> >>>
> >>> Regards,
> >>> Hridya
> >>>
> >>>>
> >>>> Thanks,
> >>> .
> >>>
> > .
> >