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From:   David Howells <dhowells@redhat.com>
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        Jingbo Xu <jefflexu@linux.alibaba.com>, houtao1@huawei.com
Subject: Re: [PATCH v2 2/2] fscache: Add the missing smp_mb__after_atomic() before wake_up_bit()
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Date:   Wed, 11 Jan 2023 16:24:59 +0000
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David Howells <dhowells@redhat.com> wrote:

> What two values are you ordering?
> 
> If we're using this to create a critical section, then yes, we would need a
> barrier to order the changes inside the critical section before changing the
> memory location that forms the lock - but this is not a critical section.

Actually, that said, the ordering is probably between the bit being cleared
and the task state.

David