[ltt-dev] UST simple example not working

George Stephen-RVGG20 RVGG20 at freescale.com
Mon Jun 21 12:01:40 EDT 2010


Hello,

 

I tried this simple example for trace_marker and get incorrect values
for  "return" in "ust.factorial" (return: 0). 

The trace for "ust.args" works. I even tried this in a C version of the
sample with same  errors.

Using g++ -o sample -g  -lust sample.cpp; usttrace ./sample on a PowerPC
target. 

 

class Factorial1 : public Factorial

{

public:

                Factorial1(){}

                virtual ~Factorial1(){}

                unsigned long long do_factorial(unsigned long long n)

                {              

                                // user space trace instrumentation

                                trace_mark(ust, args, "in_arg %d", n);

                                if (n <= 1)

                                                return 1;

                                else

                                                return n *
do_factorial(n-1);

                }

};

 

class Factorial2 : public Factorial

{

public:

                Factorial2(){}

                virtual ~Factorial2(){}

                unsigned long long do_factorial(unsigned long long n)

                {

                                unsigned long long ret = 1;

                                for ( int i = 1; i <= n; i++){

                                                ret *= i;

                                }

                                // user space trace instrumentation

                                trace_mark(ust, factorial, "in_arg %d
return %d", n, ret);                              

                                return ret;

                }

};

 

In another case I tried just: trace_mark(ust, factorial, "return %d",
ret) and the value for ret was the value for n.

 

Thanks for the help,

Stephen G.

 

                                

 

 

   

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