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ACPI: APEI: Remove redundant rcu_read_lock/unlock() under spinlock

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Since commit a8bb74acd8 ("rcu: Consolidate RCU-sched update-side
function definitions") there is no difference between rcu_read_lock(),
rcu_read_lock_bh() and rcu_read_lock_sched() in terms of RCU read
section and the relevant grace period. That means that spin_lock(),
which implies rcu_read_lock_sched(), also implies rcu_read_lock().

There is no need no explicitly start a RCU read section if one has
already been started implicitly by spin_lock().

Simplify the code and remove the inner rcu_read_lock() invocation.

Signed-off-by: pengdonglin <pengdonglin@xiaomi.com>
Signed-off-by: pengdonglin <dolinux.peng@gmail.com>
Reviewed-by: Hanjun Guo <guohanjun@huawei.com>
Link: https://patch.msgid.link/20250916044735.2316171-2-dolinux.peng@gmail.com
[ rjw: Subject adjustment ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
pengdonglin
2025-09-16 12:47:22 +08:00
committed by Rafael J. Wysocki
parent 7d444f5099
commit c7bc7e9070
1 changed files with 0 additions and 2 deletions
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2
drivers/acpi/apei/ghes.c
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@@ -1207,12 +1207,10 @@ static int ghes_notify_hed(struct notifier_block *this, unsigned long event,
int ret = NOTIFY_DONE;
spin_lock_irqsave(&ghes_notify_lock_irq, flags);
rcu_read_lock();
list_for_each_entry_rcu(ghes, &ghes_hed, list) {
if (!ghes_proc(ghes))
ret = NOTIFY_OK;
}
rcu_read_unlock();
spin_unlock_irqrestore(&ghes_notify_lock_irq, flags);
return ret;