file: add no-accelerator assertion flag

- add a new flag indicating that the user guarantueed not to use accelerator memory with a particular file. - check that flag in common_ompio_check_gpu_buf() and return immediatly `false` if the flag is set, i.e. bypassing the accelerator check_addr() routine (which is supposed to be the expensive part). Signed-off-by: Edgar Gabriel <Edgar.Gabriel@amd.com>

Author: edgargabriel

ompi/file/file.c

@@ -18,7 +18,7 @@
  * Copyright (c) 2016-2017 IBM Corporation. All rights reserved.
  * Copyright (c) 2024 Triad National Security, LLC. All rights
  * reserved.
- * Copyright (c) 2024  Advanced Micro Devices, Inc. All rights reserved.
+ * Copyright (c) 2024-2025 Advanced Micro Devices, Inc. All rights reserved.
  * $COPYRIGHT$
  *
  * Additional copyrights may follow
@@ -126,7 +126,9 @@ int ompi_file_open(struct ompi_communicator_t *comm, const char *filename,
  }
  ompi_info_memkind_assert_type type;
  ompi_info_memkind_copy_or_set (&comm->instance->super, &file->super, info, &type);
-
+ if (OMPI_INFO_MEMKIND_ASSERT_NO_ACCEL == type) {
+ file->f_flags |= OMPI_FILE_ASSERT_NO_ACCEL_BUF;
+ }
  file->f_amode = amode;
  file->f_filename = strdup(filename);
  if (NULL == file->f_filename) {

ompi/file/file.h

@@ -39,9 +39,9 @@
 /*
  * Flags
  */
-#define OMPI_FILE_ISCLOSED 0x00000001
-#define OMPI_FILE_HIDDEN 0x00000002
-
+#define OMPI_FILE_ISCLOSED  0x00000001
+#define OMPI_FILE_HIDDEN  0x00000002
+#define OMPI_FILE_ASSERT_NO_ACCEL_BUF 0x00000004
 BEGIN_C_DECLS
 
 /**

ompi/mca/common/ompio/common_ompio_buffer.c

@@ -11,6 +11,7 @@
  * All rights reserved.
  * Copyright (c) 2008-2019 University of Houston. All rights reserved.
  * Copyright (c) 2022 Amazon.com, Inc. or its affiliates. All Rights reserved.
+ * Copyright (c) 2025 Advanced Micro Devices, Inc. All rights reserved.
  * $COPYRIGHT$
  *
  * Additional copyrights may follow
@@ -47,7 +48,11 @@ void mca_common_ompio_check_gpu_buf ( ompio_file_t *fh, const void *buf, int *is
 
  *is_gpu=0;
  *is_managed=0;
- 
+
+ if (fh->f_fh->f_flags & OMPI_FILE_ASSERT_NO_ACCEL_BUF) {
+ return;
+ }
+
  if (0 < opal_accelerator.check_addr(buf, &dev_id, &flags)) {
  *is_gpu = 1;
  if (flags & MCA_ACCELERATOR_FLAGS_UNIFIED_MEMORY) {
@@ -62,16 +67,14 @@ static void* mca_common_ompio_buffer_alloc_seg ( void*ctx, size_t *size )
 {
  char *buf=NULL;
  size_t realsize, numpages;
- uint64_t flags = 0;
- int dev_id;
 
  numpages = (*size + mca_common_ompio_pagesize -1 )/mca_common_ompio_pagesize;
  realsize = numpages * mca_common_ompio_pagesize;
 
- buf = malloc ( realsize);
+ buf = malloc (realsize);
 
- if (NULL != buf && 0 == opal_accelerator.check_addr(buf, &dev_id, &flags)) {
- opal_accelerator.host_register(dev_id, (void *)buf, realsize);
+ if (NULL != buf) {
+ opal_accelerator.host_register(MCA_ACCELERATOR_NO_DEVICE_ID, (void *)buf, realsize);
  }
 
  *size = realsize;