Merge pull request #3292 from markalle/pr/ibv_reg_mr__fork

IB fork

Author: hppritcha

opal/mca/btl/openib/connect/btl_openib_connect_base.c

@@ -32,6 +32,9 @@
 #include "opal/util/proc.h"
 #include "opal/util/show_help.h"
 
+#include "opal/util/sys_limits.h"
+#include "opal/align.h"
+
 /*
  * Array of all possible connection functions
  */
@@ -421,10 +424,27 @@ int opal_btl_openib_connect_base_alloc_cts(mca_btl_base_endpoint_t *endpoint)
         sizeof(mca_btl_openib_footer_t) +
         mca_btl_openib_component.qp_infos[mca_btl_openib_component.credits_qp].size;
 
+    int align_it = 0;
+    int page_size;
+
+    page_size = opal_getpagesize();
+    if (length >= page_size / 2) { align_it = 1; }
+    if (align_it) {
+// I think this is only active for ~64k+ buffers anyway, but I'm not
+// positive, so I'm only increasing the buffer size and alignment if
+// it's not too small. That way we'd avoid wasting excessive memory
+// in case this code was active for tiny buffers.
+        length = OPAL_ALIGN(length, page_size, int);
+    }
+
     /* Explicitly don't use the mpool registration */
     fli = &(endpoint->endpoint_cts_frag.super.super.base.super);
     fli->registration = NULL;
-    fli->ptr = malloc(length);
+    if (!align_it) {
+        fli->ptr = malloc(length);
+    } else {
+        posix_memalign((void**)&(fli->ptr), page_size, length);
+    }
     if (NULL == fli->ptr) {
         BTL_ERROR(("malloc failed"));
         return OPAL_ERR_OUT_OF_RESOURCE;

opal/mca/btl/openib/connect/btl_openib_connect_udcm.c

@@ -75,6 +75,7 @@
 #include "connect/connect.h"
 
 #include "opal/util/sys_limits.h"
+#include "opal/align.h"
 
 #if (ENABLE_DYNAMIC_SL)
 #include "connect/btl_openib_connect_sl.h"
@@ -1040,16 +1041,19 @@ static void udcm_module_destroy_listen_qp (udcm_module_t *m)
 
 static int udcm_module_allocate_buffers (udcm_module_t *m)
 {
-    size_t total_size;
+    size_t total_size, page_size;
 
     m->msg_length   = sizeof (udcm_msg_hdr_t) +
         mca_btl_openib_component.num_qps * sizeof (udcm_qp_t);
 
     total_size = (udcm_recv_count + 1) * (m->msg_length +
                                           UDCM_GRH_SIZE);
 
+    page_size = opal_getpagesize();
+    total_size = OPAL_ALIGN(total_size, page_size, size_t);
+
     m->cm_buffer = NULL;
-    posix_memalign ((void **)&m->cm_buffer, (size_t)opal_getpagesize(),
+    posix_memalign ((void **)&m->cm_buffer, (size_t)page_size,
                     total_size);
     if (NULL == m->cm_buffer) {
         BTL_ERROR(("malloc failed! errno = %d", errno));

opal/util/sys_limits.c

@@ -235,13 +235,20 @@ int opal_util_init_sys_limits(char **errmsg)
 
 int opal_getpagesize(void)
 {
+    static int page_size = -1;
+
+    if (page_size != -1) {
+// testing in a loop showed sysconf() took ~5 usec vs ~0.3 usec with it cached
+        return page_size;
+    }
+
 #ifdef HAVE_GETPAGESIZE
-    return getpagesize();
+    return page_size = getpagesize();
 #elif defined(_SC_PAGESIZE )
-    return sysconf(_SC_PAGESIZE);
+    return page_size = sysconf(_SC_PAGESIZE);
 #elif defined(_SC_PAGE_SIZE)
-    return sysconf(_SC_PAGE_SIZE);
+    return page_size = sysconf(_SC_PAGE_SIZE);
 #else
-    return 65536; /* safer to overestimate than under */
+    return page_size = 65536; /* safer to overestimate than under */
 #endif
 }