converting an opal_process_name_t means the loss of one bit,
it was decided to restrict the local job id to 15 bits, so the
useful information of an opal_process_name_t can fit in 63 bits.
This commit fixes several bugs identified by @ggouaillardet and MTT:
- Fix SEGV in long send completion caused by missing update to the
request callback data.
- Add an MPI_Barrier to the fence short-cut. This fixes potential
semantic issues where messages may be received before fence is
reached.
- Ensure fragments are flushed when using request-based RMA. This
allows MPI_Test/MPI_Wait/etc to work as expected.
- Restore the tag space back to 16-bits. It was intended that the
space be expanded to 32-bits but the required change to the
fragment headers was not committed. The tag space may be expanded
in a later commit.
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
This commit fixes several bugs identified by a new multi-threaded RMA
benchmarking suite. The following bugs have been identified and fixed:
- The code that signaled the actual start of an access epoch changed
the eager_send_active flag on a synchronization object without
holding the object's lock. This could cause another thread waiting
on eager sends to block indefinitely because the entirety of
ompi_osc_pt2pt_sync_expected could exectute between the check of
eager_send_active and the conditon wait of
ompi_osc_pt2pt_sync_wait.
- The bookkeeping of fragments could get screwed up when performing
long put/accumulate operations from different threads. This was
caused by the fragment flush code at the end of both put and
accumulate. This code was put in place to avoid sending a large
number of unexpected messages to a peer. To fix the bookkeeping
issue we now 1) wait for eager sends to be active before stating
any large isend's, and 2) keep track of the number of large isends
associated with a fragment. If the number of large isends reaches
32 the active fragment is flushed.
- Use atomics to update the large receive/send tag counters. This
prevents duplicate tags from being used. The tag space has also
been updated to use the entire 16-bits of the tag space.
These changes should also fixopen-mpi/ompi#1299.
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
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>
