btl/scif: fix hang at shutdown

scif_close is not causing scif_poll in the listening thread to return
as expected. To ensure the thread exits attempt to make a local
connection to wake up the thread before calling pthread_join.

cmr=v1.8.2:reviewer=ggouaillardet

This commit was SVN r31756.

ompi/mca/btl/scif/btl_scif.h

@@ -90,6 +90,8 @@ typedef struct mca_btl_scif_module_t {
     ompi_free_list_t eager_frags;
 
     pthread_t listen_thread;
+
+    bool exiting;
 } mca_btl_scif_module_t;
 
 typedef struct mca_btl_scif_component_t {

ompi/mca/btl/scif/btl_scif_add_procs.c

@@ -117,7 +117,7 @@ static void *mca_btl_scif_connect_accept (void *arg)
 
         rc = scif_poll (&pollepd, 1, -1);
         if (1 == rc) {
-            if (SCIF_POLLIN != pollepd.revents) {
+            if (SCIF_POLLIN != pollepd.revents || mca_btl_scif_module.exiting) {
                 break;
             }
 

ompi/mca/btl/scif/btl_scif_component.c

@@ -261,6 +261,7 @@ static mca_btl_base_module_t **mca_btl_scif_component_init (int *num_btl_modules
     }
 
     base_modules[0] = &mca_btl_scif_module.super;
+    mca_btl_scif_module.exiting = false;
 
     rc = mca_btl_scif_modex_send ();
     if (OMPI_SUCCESS != rc) {

ompi/mca/btl/scif/btl_scif_module.c

@@ -111,6 +111,8 @@ mca_btl_scif_module_finalize (struct mca_btl_base_module_t *btl)
     OBJ_DESTRUCT(&mca_btl_scif_module.dma_frags);
     OBJ_DESTRUCT(&mca_btl_scif_module.eager_frags);
 
+    mca_btl_scif_module.exiting = true;
+
     /* close all open connections and release endpoints */
     if (NULL != scif_module->endpoints) {
         for (i = 0 ; i < scif_module->endpoint_count ; ++i) {
@@ -125,6 +127,8 @@ mca_btl_scif_module_finalize (struct mca_btl_base_module_t *btl)
 
     /* close the listening endpoint */
     if (-1 != mca_btl_scif_module.scif_fd) {
+        /* wake up the scif thread */
+        scif_connect (mca_btl_scif_module.scif_fd, &mca_btl_scif_module.port_id);
         scif_close (mca_btl_scif_module.scif_fd);
         pthread_join(mca_btl_scif_module.listen_thread, NULL);
     }