diff options
| author | David Dai <david.dai@linux.dev> | 2025-06-24 15:49:06 -0700 |
|---|---|---|
| committer | Tejun Heo <tj@kernel.org> | 2025-06-24 13:05:26 -1000 |
| commit | cb444006a625c60e6d4dd3753863c3c74f96aac3 (patch) | |
| tree | 3c0f23267768d24423079005885a9670aae1fad5 /kernel/rcu | |
| parent | e2a37c277c64078d5439693963fb9813fa1e6e9c (diff) | |
sched_ext, rcu: Eject BPF scheduler on RCU CPU stall panic
For systems using a sched_ext scheduler and has panic_on_rcu_stall
enabled, try kicking out the current scheduler before issuing a panic.
While there are numerous reasons for RCU CPU stalls that are not
directly attributed to the scheduler, deferring the panic gives
sched_ext an opportunity to provide additional debug info when ejecting
the current scheduler. Also, handling the event more gracefully allows
us to potentially recover the system instead of incurring additional
down time.
Suggested-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: David Dai <david.dai@linux.dev>
Signed-off-by: Tejun Heo <tj@kernel.org>
Diffstat (limited to 'kernel/rcu')
| -rw-r--r-- | kernel/rcu/tree_stall.h | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/kernel/rcu/tree_stall.h b/kernel/rcu/tree_stall.h index 486c00536207..af61b2d0d311 100644 --- a/kernel/rcu/tree_stall.h +++ b/kernel/rcu/tree_stall.h @@ -134,6 +134,13 @@ static void panic_on_rcu_stall(void) { static int cpu_stall; + /* + * Attempt to kick out the BPF scheduler if it's installed and defer + * the panic to give the system a chance to recover. + */ + if (scx_rcu_cpu_stall()) + return; + if (++cpu_stall < sysctl_max_rcu_stall_to_panic) return; |