diff options
| author | Neeraj Upadhyay <quic_neeraju@quicinc.com> | 2021-12-11 22:31:39 +0530 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@kernel.org> | 2022-02-01 17:19:02 -0800 |
| commit | 02e3024175274ed4bf7912e7a1281b300cec76b5 (patch) | |
| tree | 117698b38732fd21ccad0814910bbb4792d5bc66 /kernel/rcu/tree.h | |
| parent | a47f9f131dfe4f765e385fa90e13032eadb00bac (diff) | |
rcu/nocb: Handle concurrent nocb kthreads creation
When multiple CPUs in the same nocb gp/cb group concurrently
come online, they might try to concurrently create the same
rcuog kthread. Fix this by using nocb gp CPU's spawn mutex to
provide mutual exclusion for the rcuog kthread creation code.
[ paulmck: Whitespace fixes per kernel test robot feedback. ]
Acked-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Neeraj Upadhyay <quic_neeraju@quicinc.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Diffstat (limited to 'kernel/rcu/tree.h')
| -rw-r--r-- | kernel/rcu/tree.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h index 486fc901bd08..24dd4b0d805f 100644 --- a/kernel/rcu/tree.h +++ b/kernel/rcu/tree.h @@ -203,6 +203,8 @@ struct rcu_data { int nocb_defer_wakeup; /* Defer wakeup of nocb_kthread. */ struct timer_list nocb_timer; /* Enforce finite deferral. */ unsigned long nocb_gp_adv_time; /* Last call_rcu() CB adv (jiffies). */ + struct mutex nocb_gp_kthread_mutex; /* Exclusion for nocb gp kthread */ + /* spawning */ /* The following fields are used by call_rcu, hence own cacheline. */ raw_spinlock_t nocb_bypass_lock ____cacheline_internodealigned_in_smp; |