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>
* 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>
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 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>
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been replaced by one that locks the remote peer on first communication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>
Fix CID 1324726 (#1 of 1): Free of address-of expression (BAD_FREE):
Indeed, if a lock conflicts with the lock_all we will end up trying to
free an invalid pointer.
Fix CID 1328826 (#1 of 1): Dereference after null check (FORWARD_NULL):
This was intentional but it would be a good idea to check for
module->comm being non_NULL to be safe. Also cleaned out some checks
for NULL before free().
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
Fixed CID 1269712, 1269709, 1269706, 1269703, 1269694: Logically dead code
Remove extra NULL check as OMPI_OSC_PT2PT_REQUEST_ALLOC can never set the
request to NULL.
Fixes CID 1269668: Unchecked return value
False positive. Add (void) to indicate we do not care about the return code
from opal_hash_table_get_uint32.
Fixes CID 1324726: Free of address-of expression
Do not free lock if it was not allocated.
Fixes CID 1269658: Free of address-of expression
Never will happen but because op is always a built-in op there is no
reason to retain/release it anyway.
Signed-off-by: Nathan Hjelm <hjelmn@me.com>
Fix CID 1324733: Null pointer dereferences (FORWARD_NULL)
Fix CID 1324734: Null pointer dereferences (FORWARD_NULL)
Fix CID 1324735: Null pointer dereferences (FORWARD_NULL)
Fix CID 1324736: Null pointer dereferences (FORWARD_NULL)
Fix CID 1324737: Null pointer dereferences (FORWARD_NULL)
Fix CID 1324751: Memory - illegal accesses (USE_AFTER_FREE)
Fix CID 1324750: (USE_AFTER_FREE)
Fix CID 1324749: Memory - corruptions (USE_AFTER_FREE)
Fix CID 1324748: Memory - illegal accesses (USE_AFTER_FREE)
Fix CID 1324747: (USE_AFTER_FREE)
Fix CID 1324746: Memory - corruptions (USE_AFTER_FREE)
Add missing return on an error path.
Fix CID 1324745: Code maintainability issues (UNUSED_VALUE)
Ignore return code from barrier. It was not being used anyway.
Fix CID 1324738: Null pointer dereferences (FORWARD_NULL)
Fix CID 1324741: Null pointer dereferences (REVERSE_INULL)
module->selected_btl can not be NULL in osc/rdma during normal
operation. Removed the unnecessary NULL check.
Fix CID 1324752: Memory - illegal accesses (USE_AFTER_FREE)
Move ompi_osc_pt2pt_module_lock_remove to before the lock is freed.
Fix CID 1324744: Uninitialized variables (UNINIT)
Fix CID 1324743: Uninitialized variables (UNINIT)
This array is not used unitialized but there is no reason not to use
calloc here to silence the warning.
The following CID is a false positive: 1324742. I will mark it such in
coverity.
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
This commit updates osc/pt2pt to allocate peer object as they are
needed rather than all at once. Additionally, to help improve the
memory footprint a new synchronization structure has been added.
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
This commit fixes a bug identified by MTT that occurred when mixing
passive and active target synchronization. The bugs fixed in this
commit are:
- Do not update incoming fragment counts for any type of unbuffered
control message. These messages are out-of-band and should not be
considered towards the signal counts.
- Complete a change from using received counts to expected counts for
lock, unlock, and flush acks. Part of the change made it into
master before the rest was ready. This was preventing wakeups in
some cases.
- Turn the passive_target_access_epoch module member into a
counter. As long as at least one peer is locked we are in a
passive-target epoch and not an active target one. This fix will
ensure that fragment flags are set appropriately.
fixes#538
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
The fragment flush code tries to send the active fragment before
sending any queued fragments. This could cause osc messages to arrive
out-of-order at the target (bad). Ensure ordering by alway sending
the active fragment after sending queued fragments.
This commit also fixes a bug when a synchronization message (unlock,
flush, complete) can not be packed at the end of an existing active
fragment. In this case the source process will end up sending 1 more
fragment than claimed in the synchronization message. To fix the issue
a check has been added that fixes the fragment count if this situation
is detected.
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
This commit fixes a bug in osc/pt2pt which causes MPI_Win_unlock_all
to hang. The problem was caused by code refactoring that moved the
unlock of the local process to after the loop that waits for unlock
acks. This will cause the code to loop forever waiting on the self
ack.
Fixes#444
