Yes, it is possible, but there is some different if I will do it this way -
With the current implementation (today into a trunk) if AC_RUN_IFELSE
fails => old code of RDMACM will rise,
And by way you suggest, if we postpone the decision to a run time and
the check fails =>
we have to abort RDMACM at all, because it was compiled for working
with AF_IB.
So my question to you, if we take into account all this stuff above -
What's the right way to implement it ? What do you think ?
Thank you,
Vasily.
On 03-Mar-14 17:31, Jeff Squyres (jsquyres) wrote:
Can't you test for that at run-time?
I.e., can't you do the configure-time test to see if AF_IB exists, and if it
does, do a run-time check to see if it's useful/supported in the kernel? Or is
there a reason not to do this (e.g., it would impose a performance penalty at
run time because the check would need to be in the performance-critical code
path)?
On Mar 2, 2014, at 11:02 PM, Vasily Filipov <vas...@dev.mellanox.co.il> wrote:
some additional explanation - it could be a situation when AF_IB is defined in
user space but kernel doesn't support it.
On 03-Mar-14 08:53, Vasily Filipov wrote:
Hi Jeff,
I've committed the fixes (r30905). It is a problem to detect kernel
defines (such as AF_IB ), so we have to use AC_RUN_IFELSE macro.
Thanks,
Vasily.
On 27-Feb-14 17:09, Jeff Squyres (jsquyres) wrote:
I'm seeing this warning this morning:
-----
configure.ac:1139: warning: AC_RUN_IFELSE called without default to allow cross
c\
ompiling
../../lib/autoconf/general.m4:2748: AC_RUN_IFELSE is expanded from...
../../lib/m4sugar/m4sh.m4:639: AS_IF is expanded from...
ompi/mca/btl/openib/configure.m4:37: MCA_ompi_btl_openib_CONFIG is expanded
from.\
..
config/ompi_mca.m4:571: MCA_CONFIGURE_M4_CONFIG_COMPONENT is expanded from...
config/ompi_mca.m4:352: MCA_CONFIGURE_FRAMEWORK is expanded from...
config/ompi_mca.m4:252: MCA_CONFIGURE_PROJECT is expanded from...
config/ompi_mca.m4:39: OMPI_MCA is expanded from...
configure.ac:1139: the top level
-----
Is it necessary to AC_RUN_IFELSE here? Is AC_CHECK_DECLS not sufficient for
some reason?
It strikes me that this test you currently have in configure.m4 really should
be a run-time test, and that all you need in configure.m4 should be an
AC_CHECK_DECLS to see if AF_IB exists.
_______________________________________________
devel mailing list
de...@open-mpi.org
http://www.open-mpi.org/mailman/listinfo.cgi/devel
