[Openmp-commits] [openmp] 52d0ef3 - [OpenMP] libomp: Add itt notifications to sync dependent tasks.

[Jonathan Peyton via Openmp-commits]

Author: AndreyChurbanov
Date: 2022-05-05T11:30:59-05:00
New Revision: 52d0ef3c00fc0542630fa98a4dfdf7137fb8635f

URL: https://github.com/llvm/llvm-project/commit/52d0ef3c00fc0542630fa98a4dfdf7137fb8635f
DIFF: https://github.com/llvm/llvm-project/commit/52d0ef3c00fc0542630fa98a4dfdf7137fb8635f.diff

LOG: [OpenMP] libomp: Add itt notifications to sync dependent tasks.

Intel Inspector uses itt notifications to analyze code execution, and it
reports race conditions in dependent tasks.
This patch fixes the issue notifying Inspector on tasks dependency
synchronizations.

Differential Revision: https://reviews.llvm.org/D123042

Added: 
    

Modified: 
    openmp/runtime/src/kmp_taskdeps.cpp
    openmp/runtime/src/kmp_taskdeps.h

Removed: 
    


################################################################################
diff  --git a/openmp/runtime/src/kmp_taskdeps.cpp b/openmp/runtime/src/kmp_taskdeps.cpp
index 501830eaa7587..6c1d93a89183c 100644
--- a/openmp/runtime/src/kmp_taskdeps.cpp
+++ b/openmp/runtime/src/kmp_taskdeps.cpp
@@ -45,6 +45,9 @@ static void __kmp_init_node(kmp_depnode_t *node) {
 #ifdef KMP_SUPPORT_GRAPH_OUTPUT
   node->dn.id = KMP_ATOMIC_INC(&kmp_node_id_seed);
 #endif
+#if USE_ITT_BUILD && USE_ITT_NOTIFY
+  __itt_sync_create(node, "OMP task dep node", NULL, 0);
+#endif
 }
 
 static inline kmp_depnode_t *__kmp_node_ref(kmp_depnode_t *node) {

diff  --git a/openmp/runtime/src/kmp_taskdeps.h b/openmp/runtime/src/kmp_taskdeps.h
index 99f182bbd050f..ac6174afd3f58 100644
--- a/openmp/runtime/src/kmp_taskdeps.h
+++ b/openmp/runtime/src/kmp_taskdeps.h
@@ -25,6 +25,9 @@ static inline void __kmp_node_deref(kmp_info_t *thread, kmp_depnode_t *node) {
   kmp_int32 n = KMP_ATOMIC_DEC(&node->dn.nrefs) - 1;
   KMP_DEBUG_ASSERT(n >= 0);
   if (n == 0) {
+#if USE_ITT_BUILD && USE_ITT_NOTIFY
+    __itt_sync_destroy(node);
+#endif
     KMP_ASSERT(node->dn.nrefs == 0);
 #if USE_FAST_MEMORY
     __kmp_fast_free(thread, node);
@@ -125,11 +128,17 @@ static inline void __kmp_release_deps(kmp_int32 gtid, kmp_taskdata_t *task) {
   kmp_taskdata_t *next_taskdata;
   for (kmp_depnode_list_t *p = node->dn.successors; p; p = next) {
     kmp_depnode_t *successor = p->node;
+#if USE_ITT_BUILD && USE_ITT_NOTIFY
+    __itt_sync_releasing(successor);
+#endif
     kmp_int32 npredecessors = KMP_ATOMIC_DEC(&successor->dn.npredecessors) - 1;
 
     // successor task can be NULL for wait_depends or because deps are still
     // being processed
     if (npredecessors == 0) {
+#if USE_ITT_BUILD && USE_ITT_NOTIFY
+      __itt_sync_acquired(successor);
+#endif
       KMP_MB();
       if (successor->dn.task) {
         KA_TRACE(20, ("__kmp_release_deps: T#%d successor %p of %p scheduled "