Avoid deadlock with COI
When an asynchronous offload task is completed, COI calls the runtime to queue
a "destructor task". When the task deques are full, a dead-lock situation
arises where the OpenMP threads are inside but cannot progress because the COI
thread is stuck inside the runtime trying to find a slot in a deque.
This patch implements the solution where the task deques doubled in size when
a task is being queued from a COI thread.
Differential Revision: http://reviews.llvm.org/D20733
llvm-svn: 271319
diff --git a/openmp/runtime/src/kmp_omp.h b/openmp/runtime/src/kmp_omp.h
index fc4de0f..6a76023 100644
--- a/openmp/runtime/src/kmp_omp.h
+++ b/openmp/runtime/src/kmp_omp.h
@@ -218,6 +218,7 @@
/* kmp_thread_data_t */
kmp_int32 hd_sizeof_struct;
offset_and_size_t hd_deque;
+ offset_and_size_t hd_deque_size;
offset_and_size_t hd_deque_head;
offset_and_size_t hd_deque_tail;
offset_and_size_t hd_deque_ntasks;