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From: mathieu.desnoyers@efficios.com (Mathieu Desnoyers)
Subject: [lttng-dev] Do updaters of a cds_lfht need to be synchronized?
Date: Mon, 31 Oct 2016 15:50:45 +0000 (UTC)	[thread overview]
Message-ID: <1821874660.10064.1477929045393.JavaMail.zimbra@efficios.com> (raw)
In-Reply-To: <MWHPR11MB17756EC0046E84C041DF022398AD0@MWHPR11MB1775.namprd11.prod.outlook.com>

----- On Oct 28, 2016, at 11:40 AM, Charles Jacobsen <charles.jacobsen at primarydata.com> wrote: 

> The documentation for the lock-free hash table does not mention anything about
> synchronizing updaters (e.g., with a lock):

> [ https://lwn.net/Articles/573431/ | https://lwn.net/Articles/573431/ ]

> [ https://lwn.net/Articles/573432/ | https://lwn.net/Articles/573432/ ]

> The source for rculfhash (== cds_lfht?) also mentions in the comments that add
> and remove are lock free:

> [ https://github.com/urcu/userspace-rcu/blob/master/src/rculfhash.c |
> https://github.com/urcu/userspace-rcu/blob/master/src/rculfhash.c ]

> Is it safe to assume that cds_lfht_add, cds_lfht_add_unique, and so on, *only*
> require a surrounding rcu read lock/unlock?

> "lock free" is part of the name, so I would assume the answer is "yes".

Yes, this assumption is correct. 

Thanks, 

Mathieu 

> Thank you.

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-- 
Mathieu Desnoyers 
EfficiOS Inc. 
http://www.efficios.com 
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  reply	other threads:[~2016-10-31 15:50 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-10-28 15:40 Charles Jacobsen
2016-10-31 15:50 ` Mathieu Desnoyers [this message]
2016-10-31 16:01   ` Charles Jacobsen

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