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Date: Fri, 13 Aug 2010 13:53:57 -0700
Message-ID: <AANLkTinJ04d2Bjuv2E4OOG=35TSHArEP6cHqGUQVUoy2@mail.gmail.com>
Subject: Re: Proposal: Use hi-res clock for file timestamps
From: "Patrick J. LoPresti" <lopresti@gmail.com>
To: john stultz <johnstul@us.ibm.com>
Cc: linux-fsdevel@vger.kernel.org, linux-nfs@vger.kernel.org,
        linux-kernel <linux-kernel@vger.kernel.org>
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On Fri, Aug 13, 2010 at 12:09 PM, john stultz <johnstul@us.ibm.com> wrote:
>
> So other then "show some numbers", my only thought that might make the
> patch more attractive is that rather than a global change, or a static
> CONFIG_ option, would it maybe make more sense as a mount option?

I really like this idea.

Consider the following "revision 2" of my proposal:

1) Add a function pointer "current_fs_time" to struct super_block.

2) Replace all calls of the form:

    current_fs_time(sb);

with

  sb->current_fs_time(sb);

 3) Arrange for the default value to point to the current implementation.

These first three could be one patch.  They change no functionality;
they just enable the next step.

Finally:

  4) Add a mount option to cause sb->current_fs_time(sb) to use the
hi-res implementation.

Comments?

 - Pat