[OMPT] Reduce overhead of OMPT

* Avoid computing state needed only by OMPT unless the ompt_enabled flag is set.
* Properly handle a corner case in OMPT where team == NULL.

Patch by John Mellor-Crummey

Differential Revision: http://reviews.llvm.org/D13502

llvm-svn: 249857

3 files changed, 14 insertions, 6 deletions

diff --git a/openmp/runtime/src/kmp_csupport.c b/openmp/runtime/src/kmp_csupport.c
index a9c74cc3340..385aa1dcc01 100644
--- a/openmp/runtime/src/kmp_csupport.c
+++ b/openmp/runtime/src/kmp_csupport.c
@@ -1485,12 +1485,12 @@ __kmpc_for_static_fini( ident_t *loc, kmp_int32 global_tid )
     KE_TRACE( 10, ("__kmpc_for_static_fini called T#%d\n", global_tid));
 
 #if OMPT_SUPPORT && OMPT_TRACE
-    kmp_info_t *this_thr        = __kmp_threads[ global_tid ];
-    kmp_team_t *team            = this_thr -> th.th_team;
-    int tid = __kmp_tid_from_gtid( global_tid );
-
     if (ompt_enabled &&
         ompt_callbacks.ompt_callback(ompt_event_loop_end)) {
+        kmp_info_t *this_thr = __kmp_threads[ global_tid ];
+        kmp_team_t *team     = this_thr -> th.th_team;
+        int tid = __kmp_tid_from_gtid( global_tid );
+
         ompt_callbacks.ompt_callback(ompt_event_loop_end)(
             team->t.ompt_team_info.parallel_id,
             team->t.t_implicit_task_taskdata[tid].ompt_task_info.task_id);
diff --git a/openmp/runtime/src/kmp_sched.cpp b/openmp/runtime/src/kmp_sched.cpp
index a68c9af77d6..1977ca4d418 100644
--- a/openmp/runtime/src/kmp_sched.cpp
+++ b/openmp/runtime/src/kmp_sched.cpp
@@ -97,8 +97,14 @@ __kmp_for_static_init(
     register kmp_info_t *th = __kmp_threads[ gtid ];
 
 #if OMPT_SUPPORT && OMPT_TRACE
-    ompt_team_info_t *team_info = __ompt_get_teaminfo(0, NULL);
-    ompt_task_info_t *task_info = __ompt_get_taskinfo(0);
+    ompt_team_info_t *team_info = NULL; 
+    ompt_task_info_t *task_info = NULL; 
+
+    if (ompt_enabled) {
+        // Only fully initialize variables needed by OMPT if OMPT is enabled.
+        team_info = __ompt_get_teaminfo(0, NULL);
+        task_info = __ompt_get_taskinfo(0);
+    }
 #endif
 
     KMP_DEBUG_ASSERT( plastiter && plower && pupper && pstride );
diff --git a/openmp/runtime/src/ompt-specific.c b/openmp/runtime/src/ompt-specific.c
index d8d30dc5c01..c249e86beb1 100644
--- a/openmp/runtime/src/ompt-specific.c
+++ b/openmp/runtime/src/ompt-specific.c
@@ -50,6 +50,8 @@ __ompt_get_teaminfo(int depth, int *size)
 
     if (thr) {
         kmp_team *team = thr->th.th_team;
+        if (team == NULL) return NULL;
+
         ompt_lw_taskteam_t *lwt = LWT_FROM_TEAM(team);
 
         while(depth > 0) {