Re: [Boost-bugs] [Boost C++ Libraries] #5516: Upgrade lock is not acquired when previous upgrade lock releases if another read lock is present

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #5516: Upgrade lock is not acquired when previous upgrade lock releases if another read lock is present
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2011-12-07 23:34:31

#5516: Upgrade lock is not acquired when previous upgrade lock releases if another
read lock is present
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  Reporter:  fred@…                 |       Owner:  viboes  
      Type:  Support Requests       |      Status:  assigned
 Milestone:  To Be Determined       |   Component:  thread  
   Version:  Boost 1.42.0           |    Severity:  Problem 
Resolution:                         |    Keywords:          
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Comment (by fred@…):

 Quoted: "the thread will block until exclusive ownership can be acquired".

 In the example I gave, m3 could have acquired ownership just after m2
 released its upgradable lock, because only a read lock was taken at that
 point, by m1. And yet, it did wait until after m1 released the lock to
 acquire it.

 I understand this sentence of the documentation as meaning the acquisition
 is eager, but it seems that it is not. Is that correct?

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/5516#comment:4>
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