Re: [driver-core PATCH v8 0/9] Add NUMA aware async_schedule calls

From
Alexander Duyck <hidden>
Date
2018-12-10 23:25:06
Also in
lkml, nvdimm
Reply to
Luis Chamberlain, 2018-12-10
On Mon, 2018-12-10 at 11:22 -0800, Luis Chamberlain wrote:
On Wed, Dec 05, 2018 at 09:25:13AM -0800, Alexander Duyck wrote:
quoted
This patch set provides functionality that will help to improve the
locality of the async_schedule calls used to provide deferred
initialization.

This patch set originally started out focused on just the one call to
async_schedule_domain in the nvdimm tree that was being used to defer the
device_add call however after doing some digging I realized the scope of
this was much broader than I had originally planned. As such I went
through and reworked the underlying infrastructure down to replacing the
queue_work call itself with a function of my own and opted to try and
provide a NUMA aware solution that would work for a broader audience.

In addition I have added several tweaks and/or clean-ups to the front of the
patch set. Patches 1 through 4 address a number of issues that actually were
causing the existing async_schedule calls to not show the performance that
they could due to either not scaling on a per device basis, or due to issues
that could result in a potential deadlock. For example, patch 4 addresses the
fact that we were calling async_schedule once per driver instead of once
per device, and as a result we would have still ended up with devices
being probed on a non-local node without addressing this first.
No tests were added. Again, I think it would be good to add test
cases to showcase the old mechanisms, illustrate the new, and ensure
we don't regress both now and also help us ensure we don't regress
moving forward.

This is all too critical of a path for the kernel, and these changes
are rather instrusive. I'd readlly like to see test code for it now
rather than later.

  Luis
Sorry about that. I was more focused on the rewrite of patch 2 and
overlooked the comment about lib/test_kmod.c.

I'll look into it and see if I can squeeze it in for v9.

Thanks.

- Alex
Thread (21 messages) 21 messages, 3 authors, last reply 2018-12-10
Keyboard shortcuts
hback out one level
jnext message in thread / next series-diff position
kprevious message in thread / previous series-diff position
ldrill in
Escclose help / fold thread tree
?toggle this help