From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ingo Molnar <mingo@elte.hu>
Subject: Re: [ofa-general] Re: [GIT PULL] please pull ummunotify
Date: Tue, 13 Oct 2009 08:40:06 +0200
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To: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
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* Jason Gunthorpe <jgunthorpe@obsidianresearch.com> wrote:

> On Mon, Oct 12, 2009 at 10:20:46PM +0200, Ingo Molnar wrote:
> > It might be more acceptable because the flag-hint mechanism can at most 
> > cause over-flushing - while with perf events we might miss to invalidate 
> > a range altogether.
> 
> Right. Overflushing is not important, but missing an event entirely is 
> not recoverable (at least within the current kernel APIs).

So if we detect event loss in the perf event case (should not happen 
with sufficient buffering but it is a possibility the code should be 
prepared for) then we can just flush the [0,-1ULL] range, right?

	Ingo