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Date:   Fri, 26 May 2023 14:58:53 -0400
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Subject: Re: [RFC][PATCH 1/2] locking: Introduce __cleanup__ based guards
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To:     Waiman Long <longman@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
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From:   Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
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On 5/26/23 14:49, Waiman Long wrote:
[...]
> 
> BTW, do we have a use case for double_lock_guard/double_lock_scope? I 
> can envision a nested lock_scope inside a lock_scope, but taking 2 auto 
> locks of the same type at init time and then unlock them at exit just 
> doesn't make sense to me.

AFAIU taking both runqueue locks for source and destination runqueues on 
migration is one use-case for double_lock_guard/scope.

Thanks,

Mathieu


-- 
Mathieu Desnoyers
EfficiOS Inc.
https://www.efficios.com