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Subject: Re: [PATCH v5 3.1.0-rc4-tip 12/26]   Uprobes: Handle breakpoint and
 Singlestep
From: Peter Zijlstra <peterz@infradead.org>
To: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>, Steven Rostedt <rostedt@goodmis.org>,
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Date: Mon, 26 Sep 2011 18:25:22 +0200
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On Mon, 2011-09-26 at 21:31 +0530, Srikar Dronamraju wrote:
> * Peter Zijlstra <peterz@infradead.org> [2011-09-26 15:59:13]:
> 
> > On Tue, 2011-09-20 at 17:32 +0530, Srikar Dronamraju wrote:
> > > 						Hence provide some extra
> > > + * time (by way of synchronize_sched() for breakpoint hit threads to acquire
> > > + * the uprobes_treelock before the uprobe is removed from the rbtree. 
> > 
> > 'Some extra time' doesn't make me all warm an fuzzy inside, but instead
> > screams we fudge around a race condition.
> 
> The extra time provided is sufficient to avoid the race. So will modify
> it to mean "sufficient" instead of "some".   
> 
> Would that suffice?

Much better, for extra point, explain why its sufficient as well ;-)