This commit adds code to handle large unaligned gets. There are two
possible code paths for these transactions:
1) The remote region and local region have the same alignment. In
this case the get will be broken down into at most three get
transactions: 1 transaction to get the unaligned start of the region
(buffered), 1 transaction to get the aligned portion of the region,
and 1 transaction to get the end of the region.
2) The remote and local regions do not have the same alignment. This
should be an uncommon case and is not optimized. In this case a
buffer is allocated and registered locally to hold the aligned data
from the remote region. There may be cases where this fails (low
memory, can't register memory). Those conditions are unlikely and
will be handled later.
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
If the state of the request is not set to OMPI_REQUEST_ACTIVE
then MPI_Test would immediately signal such request completed
while hcoll may still be working on it.
Signed-off-by: Joshua Ladd <jladd.mlnx@gmail.com>
If atomics are not globally visible (cpu and nic atomics do not mix)
then a btl endpoint must be used to access local ranks. To avoid
issues that are caused by having the same region registered with
multiple handles osc/rdma was updated to always use the handle for
rank 0. There was a bug in the update that caused osc/rdma to continue
using the local endpoint for accessing the state even though the
pointer/handle are not valid for that endpoint. This commit fixes the
bug.
Fixesopen-mpi/ompi#1241.
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
This commit makes ompi_datatype_get_pack_description thread safe. The
call is used by osc/pt2pt to send the packed description to remote
peers. Before this commit if MPI_THREAD_MULTIPLE is enabled and the
user uses MPI_Put, MPI_Get, etc we could hit a race where multiple
threads attempt to store the packed description on the datatype. Since
the code in question is not performance-critical the threading fix
uses opal_atomic_* calls instead of bothering with OPAL_THREAD_*.
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
Optimizing put aggregation in the presence of threads will require a
redesign of the code. For now just ensure that put aggregation is
turned off when MPI_THREAD_MULTIPLE is enabled.
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
The eviction callback, for convenience (and to avoid code
duplication), use to call opal_hotel_checkout(). However,
opal_hotel_checkout() deletes the eviction event -- which is fine to
do when opal_hotel_checkout() is invoked by the application. But when
it's invoked by the same event that it's deleting, it can cause Bad
Things to happen.
For simplicity, instead of invoking opal_hotel_checkout() from the
eviction callback, just duplicate the checkout logic into the eviction
callback function (and skip the delete-the-evict-event part).
For good measure, put a comment in all three places where the checkout
logic occurs (because it's inlined): don't change this logic without
changing all 3 places.
Finally, also add a line in the docs for opal_hotel_init() warning
users from calling opal_hotel_checkout() from their eviction
callback.