Re: [PATCH RFC] sched: Use sched-RCU in core-scheduling balancing logic

2020-05-21 Thread Joel Fernandes
On Thu, May 21, 2020 at 6:52 PM Paul E. McKenney wrote: > > On Wed, May 20, 2020 at 06:48:18PM -0400, Joel Fernandes (Google) wrote: > > rcu_read_unlock() can incur an infrequent deadlock in > > sched_core_balance(). Fix this by using sched-RCU instead. > > > > This fixes the following spinlock

Re: [PATCH RFC] sched: Use sched-RCU in core-scheduling balancing logic

2020-05-21 Thread Paul E. McKenney
On Wed, May 20, 2020 at 06:48:18PM -0400, Joel Fernandes (Google) wrote: > rcu_read_unlock() can incur an infrequent deadlock in > sched_core_balance(). Fix this by using sched-RCU instead. > > This fixes the following spinlock recursion observed when testing the > core scheduling patches on

[PATCH RFC] sched: Use sched-RCU in core-scheduling balancing logic

2020-05-20 Thread Joel Fernandes (Google)
rcu_read_unlock() can incur an infrequent deadlock in sched_core_balance(). Fix this by using sched-RCU instead. This fixes the following spinlock recursion observed when testing the core scheduling patches on PREEMPT=y kernel on ChromeOS: [3.240891] BUG: spinlock recursion on CPU#2,