datapath: Further mirror checksum offloading state on old kernels.

[openvswitch] / lib / ovsdb-idl.c

diff --git a/lib/ovsdb-idl.c b/lib/ovsdb-idl.c
index df5aff52960217ddea1edd41dd7d3b81b61349de..94784bdaabfb236e10351da9adbcac983dffa7a8 100644 (file)
--- a/lib/ovsdb-idl.c
+++ b/lib/ovsdb-idl.c
@@ -1,4 +1,4 @@
-/* Copyright (c) 2009, 2010 Nicira Networks.
+/* Copyright (c) 2009, 2010, 2011 Nicira Networks.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -282,7 +282,7 @@ ovsdb_idl_run(struct ovsdb_idl *idl)
     assert(!idl->txn);
     jsonrpc_session_run(idl->session);
     for (i = 0; jsonrpc_session_is_connected(idl->session) && i < 50; i++) {
-        struct jsonrpc_msg *msg, *reply;
+        struct jsonrpc_msg *msg;
         unsigned int seqno;
 
         seqno = jsonrpc_session_get_seqno(idl->session);
@@ -298,7 +298,6 @@ ovsdb_idl_run(struct ovsdb_idl *idl)
             break;
         }
 
-        reply = NULL;
         if (msg->type == JSONRPC_NOTIFY
                    && !strcmp(msg->method, "update")
                    && msg->params->type == JSON_ARRAY
@@ -313,8 +312,7 @@ ovsdb_idl_run(struct ovsdb_idl *idl)
             idl->monitor_request_id = NULL;
             ovsdb_idl_clear(idl);
             ovsdb_idl_parse_update(idl, msg->result);
-        } else if (msg->type == JSONRPC_REPLY
-                   && msg->id && msg->id->type == JSON_STRING
+        } else if (msg->type == JSONRPC_REPLY && msg->id->type == JSON_STRING
                    && !strcmp(msg->id->u.string, "echo")) {
             /* It's a reply to our echo request.  Ignore it. */
         } else if ((msg->type == JSONRPC_ERROR
@@ -329,9 +327,6 @@ ovsdb_idl_run(struct ovsdb_idl *idl)
                      jsonrpc_session_get_name(idl->session),
                      jsonrpc_msg_type_to_string(msg->type));
         }
-        if (reply) {
-            jsonrpc_session_send(idl->session, reply);
-        }
         jsonrpc_msg_destroy(msg);
     }
 
@@ -1113,6 +1108,15 @@ ovsdb_idl_get(const struct ovsdb_idl_row *row,
 
     return ovsdb_idl_read(row, column);
 }
+
+/* Returns false if 'row' was obtained from the IDL, true if it was initialized
+ * to all-zero-bits by some other entity.  If 'row' was set up some other way
+ * then the return value is indeterminate. */
+bool
+ovsdb_idl_row_is_synthetic(const struct ovsdb_idl_row *row)
+{
+    return row->table == NULL;
+}
 \f
 /* Transactions. */
 
@@ -1402,12 +1406,16 @@ ovsdb_idl_txn_commit(struct ovsdb_idl_txn *txn)
         if (row->old == row->new) {
             continue;
         } else if (!row->new) {
-            struct json *op = json_object_create();
-            json_object_put_string(op, "op", "delete");
-            json_object_put_string(op, "table", class->name);
-            json_object_put(op, "where", where_uuid_equals(&row->uuid));
-            json_array_add(operations, op);
-            any_updates = true;
+            if (class->is_root) {
+                struct json *op = json_object_create();
+                json_object_put_string(op, "op", "delete");
+                json_object_put_string(op, "table", class->name);
+                json_object_put(op, "where", where_uuid_equals(&row->uuid));
+                json_array_add(operations, op);
+                any_updates = true;
+            } else {
+                /* Let ovsdb-server decide whether to really delete it. */
+            }
         } else {
             struct json *row_json;
             struct json *op;
@@ -1421,6 +1429,8 @@ ovsdb_idl_txn_commit(struct ovsdb_idl_txn *txn)
             } else {
                 struct ovsdb_idl_txn_insert *insert;
 
+                any_updates = true;
+
                 json_object_put(op, "uuid-name",
                                 json_string_create_nocopy(
                                     uuid_name_from_uuid(&row->uuid)));
@@ -1441,22 +1451,29 @@ ovsdb_idl_txn_commit(struct ovsdb_idl_txn *txn)
                                                         &class->columns[idx];
 
                     if (row->old
-                        ? !ovsdb_datum_equals(&row->old[idx], &row->new[idx],
-                                              &column->type)
-                        : !ovsdb_datum_is_default(&row->new[idx],
+                        || !ovsdb_datum_is_default(&row->new[idx],
                                                   &column->type)) {
                         json_object_put(row_json, column->name,
                                         substitute_uuids(
                                             ovsdb_datum_to_json(&row->new[idx],
                                                                 &column->type),
                                             txn));
+
+                        /* If anything really changed, consider it an update.
+                         * We can't suppress not-really-changed values earlier
+                         * or transactions would become nonatomic (see the big
+                         * comment inside ovsdb_idl_txn_write()). */
+                        if (!any_updates && row->old &&
+                            !ovsdb_datum_equals(&row->old[idx], &row->new[idx],
+                                                &column->type)) {
+                            any_updates = true;
+                        }
                     }
                 }
             }
 
             if (!row->old || !shash_is_empty(json_object(row_json))) {
                 json_array_add(operations, op);
-                any_updates = true;
             } else {
                 json_destroy(op);
             }
@@ -1638,6 +1655,24 @@ ovsdb_idl_txn_write(const struct ovsdb_idl_row *row_,
     assert(row->old == NULL ||
            row->table->modes[column_idx] & OVSDB_IDL_MONITOR);
 
+    /* If this is a write-only column and the datum being written is the same
+     * as the one already there, just skip the update entirely.  This is worth
+     * optimizing because we have a lot of columns that get periodically
+     * refreshed into the database but don't actually change that often.
+     *
+     * We don't do this for read/write columns because that would break
+     * atomicity of transactions--some other client might have written a
+     * different value in that column since we read it.  (But if a whole
+     * transaction only does writes of existing values, without making any real
+     * changes, we will drop the whole transaction later in
+     * ovsdb_idl_txn_commit().) */
+    if (row->table->modes[column_idx] == OVSDB_IDL_MONITOR
+        && ovsdb_datum_equals(ovsdb_idl_read(row, column),
+                              datum, &column->type)) {
+        ovsdb_datum_destroy(datum, &column->type);
+        return;
+    }
+
     if (hmap_node_is_null(&row->txn_node)) {
         hmap_insert(&row->table->idl->txn->txn_rows, &row->txn_node,
                     uuid_hash(&row->uuid));