usnic: certain send frag members are immutable

Ensure that they never are touched by checking in their destructors.

Reviewed-by: Jeff Squyres <jsquyres@cisco.com>
Reviewed-by: Reese Faucette <rfaucett@cisco.com>

This commit was SVN r29589.

ompi/mca/btl/usnic/btl_usnic_frag.c

@@ -172,6 +172,18 @@ send_frag_constructor(ompi_btl_usnic_send_frag_t *frag)
     frag->sf_seg_post_cnt = 0;
 }
 
+static void
+send_frag_destructor(ompi_btl_usnic_send_frag_t *frag)
+{
+    mca_btl_base_descriptor_t *desc;
+
+    /* make sure nobody twiddled these values after the constructor */
+    desc = &frag->sf_base.uf_base;
+    assert(desc->des_src == frag->sf_base.uf_src_seg);
+    assert(0 == frag->sf_base.uf_src_seg[0].seg_len);
+    /* PML may change desc->des_dst to point elsewhere, cannot assert that it
+     * still points to our embedded segment */
+}
 
 static void
 small_send_frag_constructor(ompi_btl_usnic_small_send_frag_t *frag)
@@ -202,6 +214,8 @@ small_send_frag_destructor(ompi_btl_usnic_small_send_frag_t *frag)
     fseg = &frag->ssf_segment;
     assert(fseg->ss_parent_frag == (struct ompi_btl_usnic_send_frag_t *)frag);
     assert(frag->ssf_base.sf_base.uf_type == OMPI_BTL_USNIC_FRAG_SMALL_SEND);
+    assert(frag->ssf_base.sf_base.uf_src_seg[0].seg_addr.pval ==
+           fseg->ss_base.us_payload.raw);
     OBJ_DESTRUCT(fseg);
 }
 
@@ -228,6 +242,13 @@ put_dest_frag_constructor(ompi_btl_usnic_put_dest_frag_t *pfrag)
     pfrag->uf_base.des_dst_cnt = 1;
 }
 
+static void
+put_dest_frag_destructor(ompi_btl_usnic_put_dest_frag_t *pfrag)
+{
+    assert(pfrag->uf_base.des_dst == pfrag->uf_dst_seg);
+    assert(1 == pfrag->uf_base.des_dst_cnt);
+}
+
 OBJ_CLASS_INSTANCE(ompi_btl_usnic_segment_t,
                    ompi_free_list_item_t,
                    NULL,
@@ -264,7 +285,7 @@ OBJ_CLASS_INSTANCE(ompi_btl_usnic_frag_t,
 OBJ_CLASS_INSTANCE(ompi_btl_usnic_send_frag_t,
                    ompi_btl_usnic_frag_t,
                    send_frag_constructor,
-                   NULL);
+                   send_frag_destructor);
 
 OBJ_CLASS_INSTANCE(ompi_btl_usnic_large_send_frag_t,
                    ompi_btl_usnic_send_frag_t,
@@ -279,4 +300,4 @@ OBJ_CLASS_INSTANCE(ompi_btl_usnic_small_send_frag_t,
 OBJ_CLASS_INSTANCE(ompi_btl_usnic_put_dest_frag_t,
                    ompi_btl_usnic_frag_t,
                    put_dest_frag_constructor,
-                   NULL);
+                   put_dest_frag_destructor);