Re: [PATCH 4/5] kmemtrace: SLUB hooks.

Mathieu Desnoyers
2008-08-12T15:43:36Z

* Eduard - Gabriel Munteanu (eduard.munteanu@linux360.ro) wrote:
> On Mon, Aug 11, 2008 at 05:22:37PM +0300, Pekka Enberg wrote:
> > On Mon, 2008-08-11 at 09:21 -0500, Christoph Lameter wrote:
> > > Pekka Enberg wrote:
> > >
> > > > The function call is supposed to go away when we convert kmemtrace to
> > > > use Mathieu's markers but I suppose even then we have a problem with
> > > > inlining?
> > >
> > > The function calls are overwritten with NOPs? Or how does that work?
> >
> > I have no idea. Mathieu, Eduard?
>
> Yes, the code is patched at runtime. But AFAIK markers already provide
> this stuff (called "immediate values"). Mathieu's tracepoints also do
> it. But it's not available on all arches. x86 and x86-64 work as far as
> I remember.
>

The markers present in mainline kernel does not use immediate values.
However, immediate values in tip does implement a load
immediate/test/branch for x86, x86_64 and powerpc. I also have support
for sparc64 in my lttng tree.

Mathieu

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Mathieu Desnoyers
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