diff options
| author | Zqiang <qiang.zhang@linux.dev> | 2025-08-13 21:30:02 +0800 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@kernel.org> | 2025-08-14 15:25:15 -0700 |
| commit | 42d590d100f2e47e47d974a902b9ed610e464824 (patch) | |
| tree | ab1187348ee636d0674af35dcae4d35b4d5fef92 | |
| parent | faab3ae329a6efb96995aeb72a68a99f664fed38 (diff) | |
rcu: Remove local_irq_save/restore() in rcu_preempt_deferred_qs_handler()
The per-CPU rcu_data structure's ->defer_qs_iw field is initialized
by IRQ_WORK_INIT_HARD(), which means that the subsequent invocation of
rcu_preempt_deferred_qs_handler() will always be executed with interrupts
disabled. This commit therefore removes the local_irq_save/restore()
operations from rcu_preempt_deferred_qs_handler() and adds a call to
lockdep_assert_irqs_disabled() in order to enable lockdep to diagnose
mistaken invocations of this function from interrupts-enabled code.
Signed-off-by: Zqiang <qiang.zhang@linux.dev>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
| -rw-r--r-- | kernel/rcu/tree_plugin.h | 5 |
1 files changed, 1 insertions, 4 deletions
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h index 4cd170b2d655..d85763336b3c 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -626,11 +626,10 @@ notrace void rcu_preempt_deferred_qs(struct task_struct *t) */ static void rcu_preempt_deferred_qs_handler(struct irq_work *iwp) { - unsigned long flags; struct rcu_data *rdp; + lockdep_assert_irqs_disabled(); rdp = container_of(iwp, struct rcu_data, defer_qs_iw); - local_irq_save(flags); /* * If the IRQ work handler happens to run in the middle of RCU read-side @@ -647,8 +646,6 @@ static void rcu_preempt_deferred_qs_handler(struct irq_work *iwp) */ if (rcu_preempt_depth() > 0) WRITE_ONCE(rdp->defer_qs_iw_pending, DEFER_QS_IDLE); - - local_irq_restore(flags); } /* |