Open MPI logo

Open MPI Development Mailing List Archives

  |   Home   |   Support   |   FAQ   |   all Development mailing list

Subject: [OMPI devel] Adding a BTL module implementing poll()
From: Alex Margolin (alex.margolin_at_[hidden])
Date: 2010-10-31 04:54:14


Hi,
I'm developing a new module under for BTL component to utilize an
existing distributed computing software in our lab.
I decided to write a TCP-like interface (implementing socket(),
connect(), accept(), send(), recv(), etc.) and then copy and modify
the existing BTL TCP module to create my own. I've also given
consideration to using LD_PRELOAD, but haven't gotten to it yet.

Currently, i'm having trouble with the the poll() syscall. Since the
I'm using other, "non-linux" sockets (no valid FD) with my own poll
implementation on them, I tried to replace the poll() in
opal/event/poll.c with a call to my poll in ompi/mca/btl/... and
failed to build open-mpi.
Since my poll needs to use the internal data structures of my module,
I did the following steps:
1. Create a sym-link to my .h file in opal/event/
2. in poll.c include my .h file and change the poll() syscall to call
my implementation (same interface).
3. in Makefile.am added my .h file under EXTRA_DIST, my .lo file under
libevent_la_DEPENDENCIES and my module path under ompidir.
4. tried to compile (x64): ./autogen.sh ; ./configure CFLAGS=-m64
CXXFLAGS=-m64 FFLAGS=-m64 FCFLAGS=-m64 --prefix /home/alex/huji/mpi/ ;
make ; make install
5. failed miserably:

Making install in tools/wrappers
make[2]: Entering directory `/home/alex/huji/openmpi-1.4.1/opal/tools/wrappers'
/bin/sh ../../../libtool --tag=CC --mode=link gcc -O3 -DNDEBUG -m64
-finline-functions -fno-strict-aliasing -pthread -fvisibility=hidden
-export-dynamic -o opal_wrapper opal_wrapper.o
../../../opal/libopen-pal.la -lnsl -lutil -lm
libtool: link: gcc -O3 -DNDEBUG -m64 -finline-functions
-fno-strict-aliasing -pthread -fvisibility=hidden -o
.libs/opal_wrapper opal_wrapper.o -Wl,--export-dynamic
../../../opal/.libs/libopen-pal.so -ldl -lnsl -lutil -lm -pthread
-Wl,-rpath -Wl,/home/alex/huji/mpi/lib
../../../opal/.libs/libopen-pal.so: undefined reference to `mos_poll'
collect2: ld returned 1 exit status
make[2]: *** [opal_wrapper] Error 1
make[2]: Leaving directory `/home/alex/huji/openmpi-1.4.1/opal/tools/wrappers'
make[1]: *** [install-recursive] Error 1
make[1]: Leaving directory `/home/alex/huji/openmpi-1.4.1/opal'
make: *** [install-recursive] Error 1

Can you please help me build open-mpi with my module, or suggest a
better way to do this?
Thanks,
Alex