[PATCH rcu 3/5] refscale: Correct affinity check
From: Paul E. McKenney
Date: Wed Oct 09 2024 - 14:03:34 EST
The current affinity check works fine until there are more reader
processes than CPUs, at which point the affinity check is looking for
non-existent CPUs. This commit therefore applies the same modulus to
the check as is present in the set_cpus_allowed_ptr() call.
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
---
kernel/rcu/refscale.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/rcu/refscale.c b/kernel/rcu/refscale.c
index 639d1cfc657b2..af32331ef645a 100644
--- a/kernel/rcu/refscale.c
+++ b/kernel/rcu/refscale.c
@@ -863,7 +863,7 @@ ref_scale_reader(void *arg)
goto end;
// Make sure that the CPU is affinitized appropriately during testing.
- WARN_ON_ONCE(raw_smp_processor_id() != me);
+ WARN_ON_ONCE(raw_smp_processor_id() != me % nr_cpu_ids);
WRITE_ONCE(rt->start_reader, 0);
if (!atomic_dec_return(&n_started))
--
2.40.1