ovsdb-data: Consolidate ovsdb atom and json strings.

ovsdb_atom_string and json_string are basically the same data structure
and ovsdb-server frequently needs to convert one to another.  We can
avoid that by using json_string from the beginning for all ovsdb
strings.  So, the conversion turns into simple json_clone(), i.e.
increment of a reference counter.  This change gives a moderate
performance boost in some scenarios, improves the code clarity and
may be useful for future development.

Acked-by: Mike Pattrick <mkp@redhat.com>
Acked-by: Dumitru Ceara <dceara@redhat.com>
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>

3 files changed, 11 insertions, 9 deletions

diff --git a/ovsdb/ovsdb-idlc.in b/ovsdb/ovsdb-idlc.in
index e589c1bdf..5a02c8f93 100755
--- a/ovsdb/ovsdb-idlc.in
+++ b/ovsdb/ovsdb-idlc.in
@@ -192,6 +192,7 @@ def printCIDLHeader(schemaFile):
 #include <stdbool.h>
 #include <stddef.h>
 #include <stdint.h>
+#include "openvswitch/json.h"
 #include "ovsdb-data.h"
 #include "ovsdb-idl-provider.h"
 #include "smap.h"
@@ -577,8 +578,8 @@ static void
                 print("    smap_init(&row->%s);" % columnName)
                 print("    for (size_t i = 0; i < datum->n; i++) {")
                 print("        smap_add(&row->%s," % columnName)
-                print("                 datum->keys[i].s->string,")
-                print("                 datum->values[i].s->string);")
+                print("                 json_string(datum->keys[i].s),")
+                print("                 json_string(datum->values[i].s));")
                 print("    }")
             elif (type.n_min == 1 and type.n_max == 1) or type.is_optional_pointer():
                 print("")
diff --git a/ovsdb/ovsdb-server.c b/ovsdb/ovsdb-server.c
index b34d97e29..9fe90592e 100644
--- a/ovsdb/ovsdb-server.c
+++ b/ovsdb/ovsdb-server.c
@@ -904,8 +904,9 @@ query_db_string(const struct shash *all_dbs, const char *name,
 
             datum = &row->fields[column->index];
             for (i = 0; i < datum->n; i++) {
-                if (datum->keys[i].s->string[0]) {
-                    return datum->keys[i].s->string;
+                const char *key = json_string(datum->keys[i].s);
+                if (key[0]) {
+                    return key;
                 }
             }
         }
@@ -1018,7 +1019,7 @@ query_db_remotes(const char *name, const struct shash *all_dbs,
 
             datum = &row->fields[column->index];
             for (i = 0; i < datum->n; i++) {
-                add_remote(remotes, datum->keys[i].s->string);
+                add_remote(remotes, json_string(datum->keys[i].s));
             }
         }
     } else if (column->type.key.type == OVSDB_TYPE_UUID
diff --git a/ovsdb/rbac.c b/ovsdb/rbac.c
index ff411675f..a3fe97120 100644
--- a/ovsdb/rbac.c
+++ b/ovsdb/rbac.c
@@ -53,8 +53,8 @@ ovsdb_find_row_by_string_key(const struct ovsdb_table *table,
         HMAP_FOR_EACH (row, hmap_node, &table->rows) {
             const struct ovsdb_datum *datum = &row->fields[column->index];
             for (size_t i = 0; i < datum->n; i++) {
-                if (datum->keys[i].s->string[0] &&
-                    !strcmp(key, datum->keys[i].s->string)) {
+                const char *row_key = json_string(datum->keys[i].s);
+                if (row_key[0] && !strcmp(key, row_key)) {
                     return row;
                 }
             }
@@ -113,7 +113,7 @@ ovsdb_rbac_authorized(const struct ovsdb_row *perms,
     }
 
     for (i = 0; i < datum->n; i++) {
-        const char *name = datum->keys[i].s->string;
+        const char *name = json_string(datum->keys[i].s);
         const char *value = NULL;
         bool is_map;
 
@@ -271,7 +271,7 @@ rbac_column_modification_permitted(const struct ovsdb_column *column,
     size_t i;
 
     for (i = 0; i < modifiable->n; i++) {
-        char *name = modifiable->keys[i].s->string;
+        const char *name = json_string(modifiable->keys[i].s);
 
         if (!strcmp(name, column->name)) {
             return true;