Re: [Patch] mm tracepoints

Ingo Molnar
2009-03-06T17:10:47Z

* Larry Woodman <lwoodman@redhat.com> wrote:

> > Would that be useless or controversial? We know from
> > vma->mapping which inode it maps to. Knowing which file is
> > faulting in can be useful - especially when addresses are a
> > moving target such as under PIE or with dlopen(), etc.
> >
> > Ingo
>
> Attached is the updated patch that applies and builds
> correctly (sorry I missed the lockdep tracepoints that were
> added at the last minute). [...]

Looks pretty good and useful to me. I've Cc:-ed more mm folks,
it would be nice to hear their opinion about these tracepoints.

Andrew, Nick, Peter, what do you think?

About the motivation of these tracepoints: i suspect these
tracepoints reflect your years-long experience in dealing with
various MM regressions in the enterprise space and these
tracepoints would help understand such regressions
faster/easier?

> [...] As far as the filename:offset is concerned I am working
> on that. Its not as simple as it looks because we have to
> follow a variable list of structs that can be null terminated
> several places along the way.

It's definitely not simple! I dont think it should be in this
base patch at all - it should be an add-on.

Ingo