diff options
| author | Frederic Weisbecker <frederic@kernel.org> | 2020-11-13 13:13:25 +0100 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@kernel.org> | 2021-01-06 16:24:59 -0800 |
| commit | b9ced9e1ab51ed6057ac8198fd1eeb404a32a867 (patch) | |
| tree | 9d5f5c0d1fca0a1290f181cb9eb63abd28bd4055 /kernel/rcu | |
| parent | 314202f84ddd61e4d7576ef62570ad2e2d9db06b (diff) | |
| download | linux-b9ced9e1ab51ed6057ac8198fd1eeb404a32a867.tar.bz2 | |
rcu/nocb: Set SEGCBLIST_SOFTIRQ_ONLY at the very last stage of de-offloading
This commit sets SEGCBLIST_SOFTIRQ_ONLY once toggling is otherwise fully
complete, allowing further RCU callback manipulation to be carried out
locklessly and locally.
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Neeraj Upadhyay <neeraju@codeaurora.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Inspired-by: Paul E. McKenney <paulmck@kernel.org>
Tested-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Diffstat (limited to 'kernel/rcu')
| -rw-r--r-- | kernel/rcu/tree_plugin.h | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h index 35dc9b31e9a4..8641b72f6d0d 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -2352,7 +2352,14 @@ static int __rcu_nocb_rdp_deoffload(struct rcu_data *rdp) */ rcu_nocb_lock_irqsave(rdp, flags); rcu_nocb_flush_bypass(rdp, NULL, jiffies); - rcu_nocb_unlock_irqrestore(rdp, flags); + rcu_segcblist_set_flags(cblist, SEGCBLIST_SOFTIRQ_ONLY); + /* + * With SEGCBLIST_SOFTIRQ_ONLY, we can't use + * rcu_nocb_unlock_irqrestore() anymore. Theoretically we + * could set SEGCBLIST_SOFTIRQ_ONLY with cb unlocked and IRQs + * disabled now, but let's be paranoid. + */ + raw_spin_unlock_irqrestore(&rdp->nocb_lock, flags); return ret; } |