tree f39eef3cbff582b8a470891d6546c9de1c362cc9
parent 0a887aa14c5bd187859c7558259df3901fee2342
author Rick Yiu <rickyiu@google.com> 1553861027 +0800
committer Thierry Strudel <tstrudel@google.com> 1555453258 +0000

Let blkio cgroup follow cpuset cgroup only

Some app may have different cgroup settings in cpuset and schedtune for its
threads, so let blkio follow cpuset only, which represents the app's current
state more accurately. Otherwise, if that thread is doing IO, then its
performance will be affected because its blkio group is in lower priority
group as schedtune.

ex: an app is now in top-app, but some thread of it set schedtune group to
background, and blkio follows schedtune because it is called later.

Main thread:
6:schedtune:/top-app
5:memory:/
4:cpuset:/top-app
3:cpuacct:/uid_1000/pid_8766
2:cpu:/
1:blkio:/
0::/

Some thread:
6:schedtune:/background
5:memory:/
4:cpuset:/top-app
3:cpuacct:/uid_1000/pid_8766
2:cpu:/
1:blkio:/background
0::/

Bug: 124727032
Test: blkio has same settings with cpuset
Change-Id: I9a140c7d9d93e1dd43c34c8cf066f4a62e2bf604