Messages in this thread | | | Date | Thu, 29 Nov 2007 17:13:09 -0800 | From | Bryan O'Sullivan <> | Subject | Re: Question regarding mutex locking |
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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.
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