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SubjectRe: Question regarding mutex locking
Larry Finger wrote:
> If a particular routine needs to lock a mutex, but it may be entered with that mutex already locked,
> would the following code be SMP safe?
>
> hold_lock = mutex_trylock()

The common way to deal with this is first to restructure your function
into two. One always acquires the lock, and the other (often written
with a "__" prefix) never acquires it. The never-acquire code does the
actual work, and the always-acquire function calls it.

You then refactor the callers so that you don't have any code paths on
which you can't predict whether or not the lock will be held.

<b
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