Re: [PATCH v8 00/22] Support ext4 on NV-DIMMs

From: Matthew Wilcox
Date: Wed Jul 23 2014 - 09:59:54 EST


On Wed, Jul 23, 2014 at 03:30:28PM +0300, Kirill A. Shutemov wrote:
> On Tue, Jul 22, 2014 at 03:47:48PM -0400, Matthew Wilcox wrote:
> > One of the primary uses for NV-DIMMs is to expose them as a block device
> > and use a filesystem to store files on the NV-DIMM. While that works,
> > it currently wastes memory and CPU time buffering the files in the page
> > cache. We have support in ext2 for bypassing the page cache, but it
> > has some races which are unfixable in the current design. This series
> > of patches rewrite the underlying support, and add support for direct
> > access to ext4.
>
> Matthew, as discussed before, your patchset make exessive use of
> i_mmap_mutex. Are you going to address this later? Or what's the plan?

Yes, it'll be addressed later. I have some ideas, but I'd like to get
some experience with just how bad this single mutex is before trying to
split it.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/