diff options
| author |   Paul E. McKenney <paulmck@kernel.org> | 2024-08-01 17:34:21 -0700 |
|---|---|---|
| committer |   Neeraj Upadhyay <neeraj.upadhyay@kernel.org> | 2024-08-14 16:48:10 +0530 |
| commit | 49f49266ec9d61a4d038cb4ddff4417ba793198f (patch) | |
| tree | fc5c786955ffe428f84154d2369e9a87304bf63e | |
| parent | rcu-tasks: Fix access non-existent percpu rtpcp variable in rcu_tasks_need_gpcb() (diff) | |
| download | wireguard-linux-49f49266ec9d61a4d038cb4ddff4417ba793198f.tar.xz wireguard-linux-49f49266ec9d61a4d038cb4ddff4417ba793198f.zip | |
rcu/tasks: Check processor-ID assumptions
The current mapping of smp_processor_id() to a CPU processing Tasks-RCU
callbacks makes some assumptions about layout. This commit therefore
adds a WARN_ON() to check these assumptions.
[ neeraj.upadhyay: Replace nr_cpu_ids with rcu_task_cpu_ids. ]
Signed-off-by: "Paul E. McKenney" <paulmck@kernel.org>
Signed-off-by: Neeraj Upadhyay <neeraj.upadhyay@kernel.org>
| -rw-r--r-- | kernel/rcu/tasks.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h index 72d564c84499..9fb8bb0afff7 100644 --- a/kernel/rcu/tasks.h +++ b/kernel/rcu/tasks.h @@ -357,6 +357,7 @@ static void call_rcu_tasks_generic(struct rcu_head *rhp, rcu_callback_t func, rcu_read_lock(); ideal_cpu = smp_processor_id() >> READ_ONCE(rtp->percpu_enqueue_shift); chosen_cpu = cpumask_next(ideal_cpu - 1, cpu_possible_mask); + WARN_ON_ONCE(chosen_cpu >= rcu_task_cpu_ids); rtpcp = per_cpu_ptr(rtp->rtpcpu, chosen_cpu); if (!raw_spin_trylock_rcu_node(rtpcp)) { // irqs already disabled. raw_spin_lock_rcu_node(rtpcp); // irqs already disabled. |