On Tue, Mar 04, 2025 at 03:06:32PM -0500, Steven Rostedt wrote: > On Tue, 4 Mar 2025 15:01:16 -0500 > Joel Fernandes <joelagnelf@xxxxxxxxxx> wrote: > > > Currently, RCU boost testing in rcutorture is broken because it relies on > > having RT throttling disabled. This means the test will always pass (or > > rarely fail). This occurs because recently, RT throttling was replaced > > by DL server which boosts CFS tasks even when rcutorture tried to > > disable throttling (see rcu_torture_disable_rt_throttle()). > > > > Therefore this patch prevents DL server from starting when RC torture > > sets the sysctl_sched_rt_runtime to -1. > > > > With this patch, boosting in TREE09 fails more than 50% of boost attempts > > making the test more useful. > > > > Also add a check of this to task_non_contending() because otherwise it > > throws a warning (in the case when DL server was already started before > > rcutorture started). > > > > Hmm, I wonder if dl_server caused a regression. That is, disabling rt > throttling should allow RT tasks to starve anything it wants. And some RT > applications rely on this. > > Should this include a Fixes and Cc stable? Yeah that makes sense to me, I'll include the Fixes tag in the v2. thanks, - Joel
