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From: Alexander Monakov <amonakov@ispras.ru>
To: musl@lists.openwall.com
Subject: Re: semaphore redesign
Date: Tue, 3 Mar 2015 01:40:37 +0300 (MSK)	[thread overview]
Message-ID: <alpine.LNX.2.11.1503030135000.19651@monopod.intra.ispras.ru> (raw)
In-Reply-To: <20150301175009.GE16260@port70.net>

On Sun, 1 Mar 2015, Szabolcs Nagy wrote:
> sorry
> 
> the code is ok (applications cannot rely on the barrier in case of
> failure), it can lead to surprising results if the application
> uses relaxed atomics, but it's not a conformance issue

There was some follow up on IRC with the conclusion, as I understood, that
even though the rest of memory may be unsynchronized after returning an error,
the memory holding the semaphore itself needs to be synchronized (otherwise
the decision to return an error might have been based on stale memory).

Does sem_getvalue need to synchronize memory as well?  I think it should, but
current implementation does not.

Alexander


  reply	other threads:[~2015-03-02 22:40 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-08-27  2:33 sem_getvalue conformance considerations Rich Felker
2014-08-27  7:05 ` Jens Gustedt
2014-08-27  7:43   ` Rich Felker
2014-08-27 10:43     ` Alexander Monakov
2014-08-27 13:32       ` Alexander Monakov
2014-08-27 19:06         ` Alexander Monakov
2014-08-27 21:06           ` Alexander Monakov
2014-08-28 20:47             ` Alexander Monakov
2014-08-29 22:51               ` Alexander Monakov
2014-08-30  5:12                 ` Rich Felker
2014-09-01 17:50                 ` Alexander Monakov
2015-02-27 23:21                   ` semaphore redesign Alexander Monakov
2015-02-28 15:42                     ` Rich Felker
2015-03-01 18:54                       ` Alexander Monakov
2015-03-01 17:30                     ` Szabolcs Nagy
2015-03-01 17:50                       ` Szabolcs Nagy
2015-03-02 22:40                         ` Alexander Monakov [this message]
2015-03-02 22:45                           ` Rich Felker
2015-03-01 18:24                       ` Alexander Monakov

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