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Re: nptl 0.30



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Alexander Terekhov wrote:
>>Just invert those lines to :
>>
>>lll_mutex_unlock (cbuffer->cond->__data.__lock); /* much better to call
>>futex_wake() with the mutex unlocked */
>>lll_futex_wake (futex, INT_MAX);
> 
> 
> I think that it's sufficient to wake just one single thread 
> here (in cleanup() for async.cancel region "wrapping" futex 
> wait(); I guess).

No, it's not sufficient.  There might be a thread which cannot be woken
because it arrived after the cond_signal o broadcast which might be woken.

Again, this is cancellation we are talking about.  It is not a regular
programming tool, it's far too costly.  It's used in exception
situations only.

- -- 
- --------------.                        ,-.            444 Castro Street
Ulrich Drepper \    ,-----------------'   \ Mountain View, CA 94041 USA
Red Hat         `--' drepper at redhat.com `---------------------------
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