[PATCH 0/1][SRU][F/master] [Config] lowlatency: turn off

[Paolo Pisati]

BugLink: https://bugs.launchpad.net/bugs/1873315

Impact:

Software that requires RT priority is not working anymore since we turned on
RT_GROUP_SCHED:

commit 9b039fc517876d312e7fa0955571101a299c91f5
Author: Seth Forshee <seth.forshee at canonical.com>
Date: Mon Apr 6 07:11:44 2020 -0500

UBUNTU: [Config] CONFIG_RT_GROUP_SCHED=y

This is wanted by docker, and the original reason for disabling
it no longer applied. Performance testing shows no noticible
impact when the option is enabled.

We already experienced this issue in the past (see
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1284731), but nowadays
reverting RT_GROUP_SCHED back to off would regress Docker and since RT
privileges are usually required by audio/multimedia software, it probably makes
sense to revert this change only for -lowlatency (while keeping the rest as is)
and encourage people to use -lowlatency if they hit this problem.

Fix:

Apply the attached patch

Regression potential:

None, only -lowlatency is impacted, -generic doesn't change.

Paolo Pisati (1):
  UBUNTU: [Config] lowlatency: turn off RT_GROUP_SCHED

 debian.master/config/amd64/config.flavour.generic    | 1 +
 debian.master/config/amd64/config.flavour.lowlatency | 1 +
 debian.master/config/annotations                     | 5 ++++-
 debian.master/config/arm64/config.common.arm64       | 1 +
 debian.master/config/armhf/config.common.armhf       | 1 +
 debian.master/config/config.common.ubuntu            | 1 -
 debian.master/config/i386/config.common.i386         | 1 +
 debian.master/config/ppc64el/config.common.ppc64el   | 1 +
 debian.master/config/s390x/config.common.s390x       | 1 +
 9 files changed, 11 insertions(+), 2 deletions(-)

-- 
2.25.1