Re: [RFC][PATCH 2/3] perf: Take a hot regs snapshot for traceevents

[Frederic Weisbecker]

On Wed, Mar 03, 2010 at 09:38:49AM +0100, Peter Zijlstra wrote:
> On Wed, 2010-03-03 at 07:55 +0100, Frederic Weisbecker wrote:
> >  /*
> > + * Hot regs snapshot support -- arch specific
> > + * This needs to be a macro because we want the current
> > + * frame pointer.
> > + */
> > +#ifndef PERF_SAVE_REGS
> > +#define PERF_SAVE_REGS(regs)   memset(regs, 0, sizeof(*regs));
> > +#endif
> 
> It would be nice to have the fallback at least set the current or
> calling IP, now you've basically wrecked stuff for everything !x86.


Oh I haven't wrecked that much !x86, no callchain was working on
trace events before, nor the ip was correct :-)

That said I agree with you, I'm going to reuse the CALLER_ADDRx
macros for that. This is the occasion to add a skip field
in PERF_SAVE_REGS to rewind where we want.

Thanks.

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