Sessions: same AMO hint

content/shmem_ctx_session_start.tex

@@ -97,6 +97,28 @@
     about \VAR{shmem\_ctx\_session\_config\_t} parameters.
     } \hline
 
+\sessiontablerow{\LibConstRef{SHMEM\_CTX\_SESSION\_SAME\_AMO}}{
+    The \VAR{SHMEM\_CTX\_SESSION\_SAME\_AMO} hint indicates the session will
+    contain a series of calls to AMO routines where each call performs the same
+    atomic operation (e.g., using only the \textit{increment} operation) on the
+    same datatype (e.g., only on objects of type \textit{int}).
+    As a more specific example, this hint would apply to a session that
+    includes \textit{only} calls to \FUNC{shmem\_int\_atomic\_inc}.
+    However, this hint would not apply to a session that includes both calls to
+    \FUNC{shmem\_int\_atomic\_inc} and \FUNC{shmem\_int\_atomic\_fetch},
+    because the operation \textit{fetch} differs from \textit{increment}.
+    (Similarly, this hint would not apply to a session that includes both calls to
+    \FUNC{shmem\_int\_atomic\_inc} and \FUNC{shmem\_long\_atomic\_inc},
+    because the datatype \textit{long} differs from \textit{int}.)
+    This hint does not restrict the application from calling other RMA and/or
+    signaling routines within the session.
+
+    The \VAR{total\_ops} field of \VAR{config} indicates the expected maximum
+    number of calls to \openshmem RMA routines within the session.
+    See Section~\ref{subsec:shmem_ctx_session_config_t} for details about
+    \VAR{shmem\_ctx\_session\_config\_t} parameters.
+    } \hline
+
 \sessiontableend
 
 \apinotes{

example_code/shmem_ctx_session_example.c

@@ -28,8 +28,9 @@ int main(void) {
   long config_mask;
   config.total_ops = N_UPDATES;
   config_mask = SHMEM_CTX_SESSION_TOTAL_OPS;
+  long options = SHMEM_CTX_SESSION_BATCH | SHMEM_CTX_SESSION_SAME_AMO;
 
-  shmem_ctx_session_start(ctx, SHMEM_CTX_SESSION_BATCH, &config, config_mask);
+  shmem_ctx_session_start(ctx, options, &config, config_mask);
 
   for (size_t i = 0; i < N_UPDATES; i++) {
       int random_pe = rand() % npes;