Subject: Re: linux-next: add utrace tree

From: Frederic Weisbecker <[email-masked]>
Date: Wed, 27 Jan 2010 17:01:06 +0100

On Wed, Jan 27, 2010 at 03:04:58AM -0800, Linus Torvalds wrote:
> 
> 
> On Wed, 27 Jan 2010, Peter Zijlstra wrote:
> > 
> > Right, so there's two aspects:
> > 
> >  1) concurrency when inserting the probe
> 
> That's the one I worried about. Stopping all threads will fix it, 
> obviously at a disastrous performance cost, but what do I care? As noted, 
> there are ways to do it safely with TLB switching, so it's fixable.

That said, inserting a probe is supposed to be a pretty rare
operation, stopping all threads in a process shouldn't be
painful for this aspect.