On Tue, Sep 13, 2016 at 12:53:27PM -0700, Arve Hjønnevåg wrote: > On Tue, Sep 13, 2016 at 12:32 AM, Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote: > > cgroups should be irrelevant, PI is unaware of them. > > I don't think cgroups are irrelevant. PI being unaware of them > explains the problem I described. If the task that holds the lock is > in a cgroup that has a low cpu.shares value, then boosting the task's > priority within that group does necessarily make it any more likely to > run. Thing is, for FIFO/DL the important parameters (prio and deadline resp.) are not cgroup dependent. For CFS you're right, and as per usual, cgroups will be a royal pain. While we can compute the total weight in the block chain, getting that back to a task which is stuck in a cgroup is just not going to work well. The only 'solution' I can come up with in a hurry is, when the task is boosted, move it to the root cgroup. That of course has a whole heap of problems all on its own. /me curses @ cgroups.. bloody stupid things. _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
