Re: [PATCH v8 3.2.0-rc5 1/9] uprobes: Install and remove breakpoints.

[Srikar Dronamraju <srikar@linux.vnet.ibm.com>]

* Peter Zijlstra <peterz@infradead.org> [2012-01-06 11:57:41]:

> On Fri, 2012-01-06 at 11:44 +0530, Srikar Dronamraju wrote:
> >         - consumers for the uprobe is NULL, so mmap_uprobe will not
> >           insert new breakpoints which correspond to this uprobe until
> >           or unless another consumer gets added for the same probe.
> > 
> >         - If a new consumer gets added for this probe, we reuse the
> >           uprobe struct.
> 
> Ok, and when we install a new 'first' consumer we'll again try and
> install all breakpoints ignoring those that were already there?
> 

Yes, We install breakpoints as if its the first time a probe has been
requested to be installed, including setting the UPROBES_RUN_HANDLER
flag.

We do check if existing breakpoints are around during the actual
insertion, in which case install_breakpoint() will return -EEXIST.
However register assumes EEXIST to be non-fatal, and continues as if its
successful.

-- 
Thanks and Regards
Srikar

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