Re: [ofa-general] Re: [GIT PULL] please pull ummunotify

Ingo Molnar
2009-10-13T06:40:06Z

* 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