Microsoft Developer Hoping To Land XArray Support For The Linux 4.17 Kernel

[phoronix]

Phoronix: Microsoft Developer Hoping To Land XArray Support For The Linux 4.17 Kernel

For the past several months Microsoft developer Matthew Wilcox has been working on an XArray implementation for the Linux kernel that he hopes to eventually replace the radix tree data structure. He's now hoping to land the initial XArray support in Linux 4.17...

http://www.phoronix.com/scan.php?page=news_item&px=XArrays-Possibly-For-Linux-4.17

[GraysonPeddie]

What are some use cases for XArray? Hyper-V?

[Ardje]

What are some use cases for XArray? Hyper-V?

I think everything that needs lists. Like filesystems, netfilter, almost anything I can think of.
Radix trees is a generic data structure API in the kernel used by many parts.
So this would mean a change for the core.

[Leopard]

Where is my pitchfork?

[pegasus]

He made a nice presentation of his work at linux.conf.au: https://www.youtube.com/watch?v=v0C9_Fp-co4

[cybertraveler]

Is Microsoft paying him to do this, or is it his own thing?

[fuzz]

http://lkml.iu.edu/hypermail/linux/kernel/1803.0/05817.html

On Tue, Mar 06, 2018 at 11:23:16AM -0800, Matthew Wilcox wrote:
> From: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx>
>
> The current implementation of btrfs_page_exists_in_range() gives the
> wrong answer if the workingset code has stored a shadow entry in the
> page cache. The filemap_range_has_page() function does not have this
> problem, and it's shared code, so use it instead.

I'm going to merge this patch. btrfs_page_exists_in_range was full of
bugs from the beginning so I'm more than happy to use the shared one.
Thanks.

[DanL]

http://lkml.iu.edu/hypermail/linux/k...3.0/05817.html

"ZOMG! The MS developer helped fix a btrfs bug! Get the pitchfork! Burn the witch!"

[Etherman]

Don't panic!
Of course even MS needs access to performant operating systems and file systems.

[starshipeleven]

Is Microsoft paying him to do this, or is it his own thing?

His email ends with @microsoft.com , he is probably paid by MS to do this.
(I'm subscribed to the btrfs mailing list so I see the full address, in the links in the articles it's XXXXX to block spammers)