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Date: Fri, 20 Dec 2013 13:26:11 -0500
From: Steven Rostedt <rostedt@goodmis.org>
To: Steven Rostedt <rostedt@goodmis.org>
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Subject: Re: [PATCH 09/13] sched: Add bandwidth management for sched_dl
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On Fri, 20 Dec 2013 13:23:23 -0500
Steven Rostedt <rostedt@goodmis.org> wrote:

> 
> 	CPU 0			CPU 1
> 	-----			-----
>  sched_setattr()
>  dl_overflow()
>  cpus = __dl_span_weight()
> 
> 			  cpu_down()
> 			  raw_spin_lock()
>  raw_spin_lock() /* blocks */
> 
> 
> 			  overflow = __dl_overflow(cpus-1);
> 			  raw_spin_unlock();
> 
>  /* gets lock */
>  __dl_overflow(cpus) /* all OK! */

Forgot to add:

 /* new deadline commitment added here */

> 
> 
> 
> 			  /* cpus goes to cpus - 1 making
> 			     __dl_overflow() not OK anymore */
> 

			also should have stated:

			"__dl_overflow(cpus-1) not OK anymore"


-- Steve