Re: [RFC] [PATCH 1/7] User Space Breakpoint Assistance Layer (UBP)

[Avi Kivity]

On 01/18/2010 05:43 PM, Ananth N Mavinakayanahalli wrote:
> > > Well, the alternatives are very unappealing.  Emulation and single-stepping
> > > are going to be very slow compared to a couple of jumps.
> > >        
> > So how big chunks of the address space are we talking here for uprobes?
> >      
> As Srikar mentioned, the least we start with is 1 page. Though you can
> have as many probes as you want, there are certain optimizations we can
> do, depending on the most common usecases.
>
> For eg., if you'd consider the start of a routine to be the most
> commonly traced location, most routines in a binary would generally
> start with the same instruction (say push %ebp), and we can refcount a
> slot with that instruction to be used for all probes of the same
> instruction.
>    

But then you can't follow the instruction with a jump back to the code...

--
error compiling committee.c: too many arguments to function

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