Thursday, 11 December 2014

BFS 460, linux-3.18-ck1

Announcing a resync and update of BFS for linux-3.18

BFS by itself:


-ck branded linux-3.18-ck1 patches:

3.18-ck1 patches

Uncharacteristically I found time to resync up quickly for this latest stable linux release. There are no new BFS features, but there have been a number of changes to stay in sync with mainline. Apart from keeping up with the usual churn in new releases, of which there was a modest amount this time, a number of other low level changes were committed making this much less of a trivial resync so some caution is warranted before blindly updating.

Hilf Danton pointed out a bug in the yield_to code (thanks!) which is now fixed. Since almost nothing uses this code you probably won't notice anything. He also pointed out some other now outdated components in BFS which are also updated. The above_background_load function has also been removed since the VM tweaks in older -cks no longer exist to use it. 

More substantially, I've reworked the plugged I/O code to match mainline now, which I had been reluctant to touch previously because of the deadlocks the unlocking and relocking in the scheduler code path introduced when the the first plugged I/O code made its way into BFS needing iterations of fixes - watch for any I/O misbehaviour/stalls. There are some changes to how mainline responds to idle CPUs so watch for any unusual behaviour there.

Having said that I've been using it for a while and not noticed anything out of the ordinary, but please report back if there are any issues.


Tuesday, 18 November 2014

BFS 458, linux-3.17-ck2

This is a bugfix release for the power usage regression as reported here with BFS 457.

BFS by itself:

CK branded BFS separate and combined patches:

Incremental change from BFS 457-458:


Tuesday, 11 November 2014

BFS 457, linux-3.17-ck1

Finally announcing a resync and minor update of BFS for the linux-3.17(.x) kernel releases.

Only minor updates have gone into this release apart from including one of the rework patches by Alfred Chen (thanks!) and the removal of the old KVM workaround that was no longer required with the bugfixes last release courtesy of Graysky (thanks!).

BFS by itself:

CK branded BFS separate and combined patches:

For those interested in the minor changes that made it up to 457, the incremental patches are available:


Monday, 25 August 2014

BFS 453/454/455/456 and 3.16-ck2

Here is an updated set of BFS patches with the accumulated bugfixes as debugged on this blog for kernels 3.13 to 3.16 inclusive. The main obvious bug which affected people was the ath9k module which would hang on suspend/resume. However there were likely a number of subtle bugs across the board that most people would not be aware of and even I only noticed that kvm behaved much better after this applied bugfix which stretches back to every BFS after 3.12.

In order to make up for the fact that there are numerous kernels out there based on BFS across the different versions, I have updated BFS and numbered the versions according to which base kernel they are on. Note that there are no feature backports on the older kernels, only the bugfixes, so SMT nice is only on the 3.16 BFS.


And along with that an updated ck branded release for 3.16, 3.16-ck2: