Re: [Libunwind-devel] Urgent - Help - 64 bit google profiler crashes (libunwind)

[Rajesh Balamohan]

Hi Arun,

I was able to compile with -lunwind after installing libunwind.rpm directly in my target box.

However, pprof is not interpreting the profiler output and not giving any information. I tried the unittest in google profiler

 export CPUPROFILE=/tmp/test.4
 /localdisk/google-perftools-0.8/.libs/lt-profiler1_unittest 10 10
The XOR test returns 0
PROFILE: interrupts/evictions/bytes = 45/0/424

./src/pprof --gv /localdisk/google- perftools-0.8/.libs/lt-profiler1_unittest /tmp/test.4
No nodes to print

But there seems to be some content available in pprof.

Also, I understand that there are some issues with google profiler if  function pointers are used. Is there any work around for such cases?

~Rajesh.B
 

On 2/22/07, Rajesh Balamohan <address@hidden> wrote:

Hi Arun,

Thankx again for helping out on this issue. I managed to install the rpm directly in my box. Here are the details.

address@hidden google-perftools-0.8]# rpm -q libunwind
libunwind-0.98.5-2


However, when I tried to compile google profiler, it was throwing the following error for which i made a change.

In file included from src/malloc_hook.cc:35:
src/base/linux_syscall_support.h: In function `void* sys_mmap(void*,
size_t, int, int, int, __off64_t)':
src/base/linux_syscall_support.h:339: error: invalid conversion from
`long int' to `void*'
make: *** [libtcmalloc_minimal_la-malloc_hook.lo] Error 1

If I make "src/base/linux_syscall_support.h"

339     static inline _syscall6(void *, sys_mmap,          void*, s,
                                 size_t,                   l,
int,               p,
                                 int,                      f,
int,               d,

to
static inline _syscall6(long int, sys_mmap,          void*, s,
                                 size_t,                   l,
int,               p,
                                 int,                      f,
int,               d,

After this, google profiler was compiled without any issues. However, it doesnt generate any output with pprof. Is there any other setting required??

address@hidden google-perftools-0.8]# ./profiler3_unittest
USAGE: /localdisk/google-perftools-0.8/.libs/lt-profiler3_unittest <iters> [num_threads] [filename]
   iters: How many million times to run the XOR test.
   num_threads: how many concurrent threads.
                0 or 1 for single-threaded mode,
                -# to fork instead of thread.
   filename: The name of the output profile.
             If you don't specify, set CPUPROFILE in the environment instead!
PROFILE: interrupts/evictions/bytes = 0/0/64

address@hidden google-perftools-0.8]# ./profiler3_unittest 1 10
The XOR test returns 0
PROFILE: interrupts/evictions/bytes = 273/5/784

address@hidden google-perftools-0.8]# pprof --text /localdisk/google-perftools-0.8/.libs/lt-profiler1_unittest /tmp/test.3

On 2/21/07, Arun Sharma < address@hidden> wrote:

On 2/20/07, Rajesh Balamohan < address@hidden> wrote:
> Hi Arun,
>
> I have raised a bug in source forge for it. I still get that error with
> make.
>
> make LDFLAGS="-lunwind -lunwind-x86_64"
> /bin/sh ./libtool --mode=link g++  -g -O2  -lunwind -lunwind-x86_64 -o
> stacktrace_unittest  stacktrace_unittest.o     libstacktrace.la
> g++ -g -O2 -o .libs/stacktrace_unittest stacktrace_unittest.o
> /usr/local/lib/libunwind-x86_64.a
> /usr/local/lib/libunwind.a -lgcc -lc ./.libs/libstacktrace.so -Wl,--rpath
> -Wl,/usr/local/lib
> ./.libs/libstacktrace.so: undefined reference to `_ULx86_64_step'
> ./.libs/libstacktrace.so: undefined reference to `_ULx86_64_get_reg'
> ./.libs/libstacktrace.so: undefined reference to `_ULx86_64_init_local'
> collect2: ld returned 1 exit status
> make: *** [stacktrace_unittest] Error 1

Actually, you don't need -lunwind-x86_64 to link. -lunwind should be
sufficient. On my machine:

$ nm /usr/lib/libunwind.so |grep _ULx86_64_step
0000000000007330 T _ULx86_64_step

libunwind.a - does "local" unwinding for the architecture it was compiled for
libunwind-${ARCH}.a - does "remote" unwinding for a different architecture.

google-perftools require only local unwinding.

-Arun

--
~Rajesh.B

--
~Rajesh.B

-- 
~Rajesh.B

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