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SubjectRe: [PATCH 1/2] locking: Provide a low overhead do_arch_spin_lock() API
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On 9/21/22 18:06, Steven Rostedt wrote:
> On Wed, 21 Sep 2022 09:21:51 -0400
> Waiman Long <longman@redhat.com> wrote:
>
>> There are some code paths in the kernel like tracing or rcu where they
>> want to use a spinlock without the lock debugging overhead (lockdep,
>> etc). Provide a do_arch_spin_lock() API with proper preemption disabling
>> and enabling without any debugging or tracing overhead.
>>
>> Signed-off-by: Waiman Long <longman@redhat.com>
> Please don't do this. arch_spin_lock() is very special, and if tracing did
> it wrong, then it needs to be fixed in the tracing code.
>
> Let's not add handlers to make it easier to use arch_spin_lock(). Tracing
> is special and arch_spin_lock() helps keep it from tracing itself.

That makes sense to me. Will remove this patch.

Thanks,
Longman

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