[Openmp-commits] [openmp] 49fabd9 - [openmp] Do not use shared memory on Android

[Pirama Arumuga Nainar via Openmp-commits]

Author: Pirama Arumuga Nainar
Date: 2021-08-09T09:41:32-07:00
New Revision: 49fabd9d76b470e3d3fdd47011826207a4e4a8eb

URL: https://github.com/llvm/llvm-project/commit/49fabd9d76b470e3d3fdd47011826207a4e4a8eb
DIFF: https://github.com/llvm/llvm-project/commit/49fabd9d76b470e3d3fdd47011826207a4e4a8eb.diff

LOG: [openmp] Do not use shared memory on Android

Android provides ashmem/ASharedMemory support on newer releases, which
we can use if requested by openmp users on Android.

Also refactor the preprocessor check for using shared memory to
kmp_config.h.cmake.

Differential Revision: https://reviews.llvm.org/D107181

Added: 
    

Modified: 
    openmp/runtime/src/kmp_config.h.cmake
    openmp/runtime/src/kmp_runtime.cpp

Removed: 
    


################################################################################
diff  --git a/openmp/runtime/src/kmp_config.h.cmake b/openmp/runtime/src/kmp_config.h.cmake
index 93a3e2f99071a..40d20115c9ec0 100644
--- a/openmp/runtime/src/kmp_config.h.cmake
+++ b/openmp/runtime/src/kmp_config.h.cmake
@@ -134,4 +134,9 @@
 # define KMP_GOMP_COMPAT
 #endif
 
+// use shared memory with dynamic library (except Android, where shm_*
+// functions don't exist).
+#if KMP_OS_UNIX && KMP_DYNAMIC_LIB && !__ANDROID__
+#define KMP_USE_SHM
+#endif
 #endif // KMP_CONFIG_H

diff  --git a/openmp/runtime/src/kmp_runtime.cpp b/openmp/runtime/src/kmp_runtime.cpp
index 65a590037e877..3bbf6e985b93c 100644
--- a/openmp/runtime/src/kmp_runtime.cpp
+++ b/openmp/runtime/src/kmp_runtime.cpp
@@ -6595,7 +6595,7 @@ void __kmp_register_library_startup(void) {
 
     char *value = NULL; // Actual value of the environment variable.
 
-#if KMP_OS_UNIX && KMP_DYNAMIC_LIB // shared memory is with dynamic library
+#if defined(KMP_USE_SHM)
     char *shm_name = __kmp_str_format("/%s", name);
     int shm_preexist = 0;
     char *data1;
@@ -6700,7 +6700,7 @@ void __kmp_register_library_startup(void) {
       } break;
       case 2: { // Neighbor is dead.
 
-#if KMP_OS_UNIX && KMP_DYNAMIC_LIB // shared memory is with dynamic library
+#if defined(KMP_USE_SHM)
         // close shared memory.
         shm_unlink(shm_name); // this removes file in /dev/shm
 #else
@@ -6714,7 +6714,7 @@ void __kmp_register_library_startup(void) {
       }
     }
     KMP_INTERNAL_FREE((void *)value);
-#if KMP_OS_UNIX && KMP_DYNAMIC_LIB // shared memory is with dynamic library
+#if defined(KMP_USE_SHM)
     KMP_INTERNAL_FREE((void *)shm_name);
 #endif
   } // while
@@ -6727,7 +6727,7 @@ void __kmp_unregister_library(void) {
   char *name = __kmp_reg_status_name();
   char *value = NULL;
 
-#if KMP_OS_UNIX && KMP_DYNAMIC_LIB // shared memory is with dynamic library
+#if defined(KMP_USE_SHM)
   char *shm_name = __kmp_str_format("/%s", name);
   int fd1 = shm_open(shm_name, O_RDONLY, 0666);
   if (fd1 == -1) {
@@ -6748,14 +6748,14 @@ void __kmp_unregister_library(void) {
   KMP_DEBUG_ASSERT(__kmp_registration_str != NULL);
   if (value != NULL && strcmp(value, __kmp_registration_str) == 0) {
 //  Ok, this is our variable. Delete it.
-#if KMP_OS_UNIX && KMP_DYNAMIC_LIB // shared memory is with dynamic library
+#if defined(KMP_USE_SHM)
     shm_unlink(shm_name); // this removes file in /dev/shm
 #else
     __kmp_env_unset(name);
 #endif
   }
 
-#if KMP_OS_UNIX && KMP_DYNAMIC_LIB // shared memory is with dynamic library
+#if defined(KMP_USE_SHM)
   KMP_INTERNAL_FREE(shm_name);
 #endif