Re: workqueue semantics [was Re: How to identify specific wait-state for a "DE" process?]

[Paul Goyette <paul%vps1.whooppee.com@localhost>]

On Wed, 6 Jan 2016, Taylor R Campbell wrote:

>   Date: Tue, 5 Jan 2016 21:48:42 -0500
>   From: Thor Lancelot Simon <tls%panix.com@localhost>
>
>   You can probably use workqueues for this.  Looking at the manual page
>   again for the first time in years, I think it's a little misleading --
>   what I believe is meant by "A work must not be enqueued again until the
>   callback is called..." is really "a work item must not be re-enqueued
>   before it has been processed by the *func callback", not the alternate,
>   crazy reading that would imply workqueues can only have one enqueued
>   item at a time.
>
> Your reading of the man page is correct: it is the struct work, not
> the struct workqueue *, that may not be reused until the callback is
> run.
>
> (I'm not sure how this would help for pgoyette's application, though.)

I don't know how it would help, either.  The best I can think of is to 
have a periodic task run which checks to see if the file descriptor is 
being closed;  if yes, then the code could release the reference and 
wake up the condvar waiter.  But is this really a good thing to do?  And 
what would be an appropriate interval?


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