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[Bug translator/11089] New: process.mark() probes with same name trigger wrongly


When a process.mark() probe is in the .probes section multiple times with
different addresses it looks like only one address is being triggered for a
probe on the mark() for that name (and it is triggered multiple times for that
one address).

One example is the cxxclass.exp test on i386:

> $ stap ./systemtap.base/cxxclass.stp cxxclass.exe -c ./cxxclass.exe
> main_enter
> call: 64
> cons call: 64
> cons call: 64
> meth call: 64 24
> meth call: 64 24
> dest call: 42
> dest call: 42
> call2: 24
> main_exit
> 
> Seems there is double call on process.mark.

The issue seems to be that some of the static probe points get
duplicated in the code. This shouldn't be a problem, and the .probes
section does contain both places with different addresses. You can also
see (with enough -vvvvv) that stap finds both locations while resolving
the mark("cons") probe. But, only the first is registered twice, as can
be seen in the generated code:

  { .address=(unsigned
long)0x8048476ULL,
.pp="process(\"/home/mark/src/systemtap/testsuite/cxxclass.exe\").statement(134513782)",
.ph=&probe_1895, },
  { .address=(unsigned
long)0x8048476ULL,
.pp="process(\"/home/mark/src/systemtap/testsuite/cxxclass.exe\").statement(134513782)",
.ph=&probe_1895, },

This means the first call of the constructor is triggered as probe twice
(as is the method, and destructor call) but the second call isn't
triggered as probe at all.

It looks like this is a problem in how sdt_query::convert_location() is
called (it seems to do duplication detection based on probe name, but
not address. I haven't looked very deeply into it yet though.

-- 
           Summary: process.mark() probes with same name trigger wrongly
           Product: systemtap
           Version: unspecified
            Status: NEW
          Severity: normal
          Priority: P2
         Component: translator
        AssignedTo: systemtap at sources dot redhat dot com
        ReportedBy: mjw at redhat dot com


http://sourceware.org/bugzilla/show_bug.cgi?id=11089

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