Re: [PATCH] loop: change fsync to fdatasync when update dio

[Christoph Hellwig]

On Thu, Jan 26, 2023 at 02:16:57PM +0900, Huijin Park wrote:
> In general, fsync has a larger overhead than fdatasync. And since the
> dio option is for data, it seems like fdatasync is enough.
> So this patch changes it to fdatasync which has little load relatively.

The only difference is that fsync also syncs the timestamps.  So this
change looks correct, but also a bit useless given that buffered to
direct I/O or back changes aren't exactly a fast path.