[Openmp-commits] [openmp] 73bb8d9 - [OpenMP] Fix child processes to use affinity_none (#91391)

[via Openmp-commits]

Author: Jonathan Peyton
Date: 2024-05-08T09:23:50-05:00
New Revision: 73bb8d9d92f689863c94d48517e89d35dae0ebcf

URL: https://github.com/llvm/llvm-project/commit/73bb8d9d92f689863c94d48517e89d35dae0ebcf
DIFF: https://github.com/llvm/llvm-project/commit/73bb8d9d92f689863c94d48517e89d35dae0ebcf.diff

LOG: [OpenMP] Fix child processes to use affinity_none (#91391)

When a child process is forked with OpenMP already initialized, the
child process resets its affinity mask and sets proc-bind-var to false
so that the entire original affinity mask is used. This patch corrects
an issue with the affinity initialization code setting affinity to
compact instead of none for this special case of forked children.

The test trying to catch this only testing explicit setting of
KMP_AFFINITY=none. Add test run for no KMP_AFFINITY setting.

Fixes: #91098

Added: 
    

Modified: 
    openmp/runtime/src/kmp_settings.cpp
    openmp/runtime/test/affinity/redetect.c

Removed: 
    


################################################################################
diff  --git a/openmp/runtime/src/kmp_settings.cpp b/openmp/runtime/src/kmp_settings.cpp
index b9c8289b5c51c..8b6092cb1085c 100644
--- a/openmp/runtime/src/kmp_settings.cpp
+++ b/openmp/runtime/src/kmp_settings.cpp
@@ -6420,6 +6420,8 @@ void __kmp_env_initialize(char const *string) {
         }
         if ((__kmp_nested_proc_bind.bind_types[0] != proc_bind_intel) &&
             (__kmp_nested_proc_bind.bind_types[0] != proc_bind_default)) {
+          if (__kmp_nested_proc_bind.bind_types[0] == proc_bind_false)
+            __kmp_affinity.type = affinity_none;
           if (__kmp_affinity.type == affinity_default) {
             __kmp_affinity.type = affinity_compact;
             __kmp_affinity.flags.dups = FALSE;

diff  --git a/openmp/runtime/test/affinity/redetect.c b/openmp/runtime/test/affinity/redetect.c
index dba83b72cc42e..4b96d1bd92ee7 100644
--- a/openmp/runtime/test/affinity/redetect.c
+++ b/openmp/runtime/test/affinity/redetect.c
@@ -1,4 +1,5 @@
 // RUN: %libomp-compile
+// RUN: %libomp-run
 // RUN: env KMP_AFFINITY=none %libomp-run
 // REQUIRES: linux