Sockets tapset and script

David Smith dsmith@redhat.com
Tue Nov 28 23:57:00 GMT 2006


Mike Mason wrote:
> Martin Hunt wrote:
>> On Fri, 2006-11-17 at 14:26 -0800, Mike Mason wrote:
>> Since yesterday, we can now access parameters in return probes (BZ
>> 1382). This could simplify some of your script because yo no longer need
>> to cache parameters on entry probes and then lookup their values in the
>> return probe.
> 
> Based on later posts, I assume this still doesn't work and I shouldn't 
> remove the parameter caching in my script just yet.
> Please confirm if this is true.

Accessing target variables in return probes currently works, for some 
applications.

There are two major outstanding bugs:

(1) The current code can get confused and fail to find the cached 
parameters if two different threads intersperse function entries/exits. 
  I should have this one fixed late today or early tomorrow.

(2) Accessing the target variables in a loop is broken.  A workaround is 
to assign the target variable to a temp variable before the loop and 
then use the temp variable in the loop.  This one is going to require 
some re-architecture work, so I'm unsure when it will get fixed.

-- 
David Smith
dsmith@redhat.com
Red Hat
http://www.redhat.com
256.217.0141 (direct)
256.837.0057 (fax)



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