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From: Mike Galbraith <umgwanakikbuti@gmail.com>
To: jimmie.davis@l-3com.com
Cc: luto@amacapital.net, oneukum@suse.de, artem_fetishev@epam.com,
	peterz@infradead.org, kosaki.motohiro@jp.fujitsu.com,
	linux-kernel@vger.kernel.org
Subject: RE: Bug 71331 - mlock yields processor to lower priority process
Date: Thu, 27 Mar 2014 06:35:35 +0100	[thread overview]
Message-ID: <1395898535.5512.72.camel@marge.simpson.net> (raw)
In-Reply-To: <FFF95760268D324AB6DD9426E83C8DF70B2E725C@ARLEXCHMBX01.lst.link.l-3com.com>

On Thu, 2014-03-27 at 04:20 +0000, jimmie.davis@l-3com.com wrote: 


> The example code submitted into bugzilla (chase back on the thread a
> bit, there is a reference) shows the problem.
> 
> Two threads, TaskA (high priority) and TaskB (low priority).  Assigned
> to the same processor, explicitly for the guarantee that only one of
> them can execute at a time.

Your priority based serialization guarantee does not exist.  Tasks can
be and are put to sleep.  When that happens, a lower priority runnable
task will run.  Whether you like that fact or not, it remains a fact.

If you don't want your lower priority task to run, why do you wake it?.

-Mike
> 



  reply	other threads:[~2014-03-27  5:35 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-03-21 20:02 Artem Fetishev
2014-03-21  9:23 ` Mike Galbraith
2014-03-21 12:18   ` jimmie.davis
2014-03-21 13:14     ` Mike Galbraith
2014-03-21 14:34       ` jimmie.davis
2014-03-21 14:54         ` Motohiro Kosaki
2014-03-21 13:35     ` Oliver Neukum
2014-03-21 14:01       ` jimmie.davis
2014-03-21 14:41         ` Mike Galbraith
2014-03-21 14:50           ` jimmie.davis
2014-03-27  0:39             ` Andy Lutomirski
2014-03-27  4:20               ` jimmie.davis
2014-03-27  5:35                 ` Mike Galbraith [this message]
2014-03-27  6:02             ` Robert Hancock
2014-03-27 11:37               ` jimmie.davis

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