This commit fixes a number of threading issues discovered in
osc/pt2pt. This includes:
- Lock the synchronization object not the module in osc_pt2pt_start.
This fixes a race between the start function and processing post
messages.
- Always lock before calling cond_broadcast. Fixes a race between
the waiting thread and signaling thread.
- Make all atomically updated values volatile.
- Make the module lock recursive to protect against some deadlock
conditions. Will roll this back once the locks have been
re-designed.
- Mark incoming complete *after* completing an accumulate not
before. This was causing an incorrect answer under certain
conditions.
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
Using MPI_MINLOC or MPI_MAXLOC with the following data types
leads to data corruption:
* MPI_DOUBLE_INT
* MPI_LONG_INT
* MPI_SHORT_INT
* MPI_LONG_DOUBLE_INT
Detect this print a error message and abort.
This workaround should be removed once the following issue is resolved:
* https://github.com/open-mpi/ompi/issues/1666
Signed-off-by: Joshua Hursey <jhursey@us.ibm.com>
* When using `MPI_Put` with `MPI_Win_lock_all` a hang is possible since
the `put` is waiting on `eager_send_active` to become `true` but
that variable might not be reset in the case of `MPI_Win_lock_all`
depending on other incoming events (e.g., `post` or ACKs of lock
requests.
Signed-off-by: Joshua Hursey <jhursey@us.ibm.com>
* When using `MPI_Lock`/`MPI_Unlock` with `MPI_Get` and non-contiguous
datatypes is is possible that the unlock finishes too early before
the data is actually present in the recv buffer.
* We need to wait for the irecv to complete before unlocking the target.
This commit waits for the outgoing fragment counts to become equal
before unlocking.
Signed-off-by: Joshua Hursey <jhursey@us.ibm.com>
* If the user uses PSCW synchronization after a Fence then the previous
epoch is not reset which can cause the PSCW to transfer data before
it is ready leading to wrong answers.
* This commit resets the `eager_send_active` in the start call.
Signed-off-by: Joshua Hursey <jhursey@us.ibm.com>
Instead of ompi_datatype_get_extent(), use ompi_datatype_get_true_extent()
to get the local and remote lower bound. For derived types like
subarray, true_lb is the correct offset for RDMA operations.
Instead of ompi_datatype_get_extent(), use ompi_datatype_get_true_extent()
to get the origin and target lower bound. For derived types like
subarray, true_lb is the correct offset for RDMA operations. Also,
instead of the extent use the size of the datatype.
This commit fixes a typo in compare-and-swap when retrieving the
memory region associated with a displacement. It was erroneously 8
bytes instead of the datatype size. This can cause an incorrect RMA
range error when the compare-and-swap is less than 4 bytes from the
end of the region.
Fixedopen-mpi/ompi#2080
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
This commit adds support for using network AMOs for MPI_Accumulate,
MPI_Fetch_and_op, and MPI_Compare_and_swap. This support is only
enabled if the ompi_single_intrinsic info key is specified or the
acc_single_interinsic MCA variable is set. This configuration
indicates to this implementation that no long accumulates will be
performed since these do not currently mix with the AMO
implementation.
This commit also cleans up the code somwhat. This includes removing
unnecessary struct keywords where the type is also typedef'd.
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
This commit cleans up some code in the passive target path. The code
used the buffered frag control send path but it is more appropriate to
use the unbuffered one. This avoids checking structures that are
should not be in use in this path.
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
This commit fixes an ordering bug in the code that keeps track of all
attached memory windows. The code is intended to keep the memory
regions sorted but was often inserting at the wrong index. Thanks to
Christoph Niethammer for reporting the issue. The reproducer will be
added to nightly MTT testing.
Fixesopen-mpi/ompi#2012
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
It is possible for another thread to process a lock ack before the
peer is set as locked. In this case either setting the locked or the
eager active flag might clobber the other thread. To address this the
flags have been made volatile and are set atomically. Since there is
no a opal_atomic_or or opal_atomic_and function just use cmpset for
now.
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
This commit fixes some bugs uncovered during thread testing of
2.0.1rc1. With these fixes the component is running cleanly with
threads.
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
This commit changes the sematics of ompi request callbacks. If a
request's callback has freed or re-posted (using start) a request
the callback must return 1 instead of OMPI_SUCCESS. This indicates
to ompi_request_complete that the request should not be modified
further. This fixes a race condition in osc/pt2pt that could lead
to the req_state being inconsistent if a request is freed between
the callback and setting the request as complete.
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
The original lock_all algorithm in osc/pt2pt sent a lock message to
each peer in the communicator even if the peer is never the target of
an operation. Since this scales very poorly the implementation has
been replaced by one that locks the remote peer on first communication
after a call to MPI_Win_lock_all.
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
This commit fixes an issue that can occur if a target gets overwhelmed with
requests. This can cause osc/pt2pt to go into deep recursion with a stack
like req_complete_cb -> ompi_osc_pt2pt_callback -> start -> req_complete_cb
-> ... . At small scale this is fine as the recursion depth stays small but
at larger scale we can quickly exhaust the stack processing frag requests.
To fix the issue the request callback now simply puts the request on a
list and returns. The osc/pt2pt progress function then handles the
processing and reposting of the request.
As part of this change osc/pt2pt can now post multiple fragment receive
requests per window. This should help prevent a target from being overwhelmed.
Signed-off-by: Nathan Hjelm <hjelmn@me.com>
It is possible for the start call to complete the requests. For this
reason the module rdma_frag field should be filled in before start is
called. If the request completes the completion callback will reset
the rdma_frag field to NULL. Fixes a bug discovered by @tkordenbrock.
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
This commit expands the OPAL_THREAD macros to include 32- and 64-bit
atomic swap. Additionally, macro declararations have been updated to
include both OPAL_THREAD_* and OPAL_ATOMIC_*. Before this commit the
former was used with add and the later with cmpset.
Signed-off-by: Nathan Hjelm <hjelmn@me.com>
This commit fixes a bug in the RDMA compare-and-swap implementation
that caused the origin value to always be written even if the compare
should have failed.
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
Need to increment the total size after checking the local offset not
before. This typo causes large allocations with MPI_Win_allocate() to
fail.
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
* mpi/start: fix bugs in cm and ob1 start functions
There were several problems with the implementation of start in Open
MPI:
- There are no checks whatsoever on the state of the request(s)
provided to MPI_Start/MPI_Start_all. It is erroneous to provide an
active request to either of these calls. Since we are already
looping over the provided requests there is little overhead in
verifying that the request can be started.
- Both ob1 and cm were always throwing away the request on the
initial call to start and start_all with a particular
request. Subsequent calls would see that the request was
pml_complete and reuse it. This introduced a leak as the initial
request was never freed. Since the only pml request that can
be mpi complete but not pml complete is a buffered send the
code to reallocate the request has been moved. To detect that
a request is indeed mpi complete but not pml complete isend_init
in both cm and ob1 now marks the new request as pml complete.
- If a new request was needed the callbacks on the original request
were not copied over to the new request. This can cause osc/pt2pt
to hang as the incoming message callback is never called.
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
* osc/pt2pt: add request for gc after starting a new request
Starting a new receive may cause a recursive call into the pt2pt
frag receive function. If this happens and the prior request is
on the garbage collection list it could cause problems. This commit
moves the gc insert until after the new request has been posted.
Signed-off-by: Nathan Hjelm <hjelmn@me.com>
* Remodel the request.
Added the wait sync primitive and integrate it into the PML and MTL
infrastructure. The multi-threaded requests are now significantly
less heavy and less noisy (only the threads associated with completed
requests are signaled).
* Fix the condition to release the request.
