X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=lib%2Fovsdb-idl.c;h=df5aff52960217ddea1edd41dd7d3b81b61349de;hb=8ba43fbd1f14d60a2d097bafc7d0606d860d0f72;hp=2132f9fefb8635142ff3908d2193d7396c026ddb;hpb=e85bbd75f7eafe06edcd3edf88bb685e1541bcfe;p=sliver-openvswitch.git diff --git a/lib/ovsdb-idl.c b/lib/ovsdb-idl.c index 2132f9fef..df5aff529 100644 --- a/lib/ovsdb-idl.c +++ b/lib/ovsdb-idl.c @@ -36,7 +36,7 @@ #include "util.h" #include "vlog.h" -VLOG_DEFINE_THIS_MODULE(ovsdb_idl) +VLOG_DEFINE_THIS_MODULE(ovsdb_idl); /* An arc from one idl_row to another. When row A contains a UUID that * references row B, this is represented by an arc from A (the source) to B @@ -66,7 +66,7 @@ struct ovsdb_idl { const struct ovsdb_idl_class *class; struct jsonrpc_session *session; struct shash table_by_name; - struct ovsdb_idl_table *tables; + struct ovsdb_idl_table *tables; /* Contains "struct ovsdb_idl_table *"s.*/ struct json *monitor_request_id; unsigned int last_monitor_request_seqno; unsigned int change_seqno; @@ -140,13 +140,29 @@ static bool ovsdb_idl_txn_process_reply(struct ovsdb_idl *, * form acceptable to jsonrpc_session_open(). The connection will maintain an * in-memory replica of the remote database whose schema is described by * 'class'. (Ordinarily 'class' is compiled from an OVSDB schema automatically - * by ovsdb-idlc.) */ + * by ovsdb-idlc.) + * + * If 'monitor_everything_by_default' is true, then everything in the remote + * database will be replicated by default. ovsdb_idl_omit() and + * ovsdb_idl_omit_alert() may be used to selectively drop some columns from + * monitoring. + * + * If 'monitor_everything_by_default' is false, then no columns or tables will + * be replicated by default. ovsdb_idl_add_column() and ovsdb_idl_add_table() + * must be used to choose some columns or tables to replicate. + */ struct ovsdb_idl * -ovsdb_idl_create(const char *remote, const struct ovsdb_idl_class *class) +ovsdb_idl_create(const char *remote, const struct ovsdb_idl_class *class, + bool monitor_everything_by_default) { struct ovsdb_idl *idl; + uint8_t default_mode; size_t i; + default_mode = (monitor_everything_by_default + ? OVSDB_IDL_MONITOR | OVSDB_IDL_ALERT + : 0); + idl = xzalloc(sizeof *idl); idl->class = class; idl->session = jsonrpc_session_open(remote); @@ -160,7 +176,8 @@ ovsdb_idl_create(const char *remote, const struct ovsdb_idl_class *class) shash_add_assert(&idl->table_by_name, tc->name, table); table->class = tc; table->modes = xmalloc(tc->n_columns); - memset(table->modes, OVSDB_IDL_MODE_RW, tc->n_columns); + memset(table->modes, default_mode, tc->n_columns); + table->need_table = false; shash_init(&table->columns); for (j = 0; j < tc->n_columns; j++) { const struct ovsdb_idl_column *column = &tc->columns[j]; @@ -215,15 +232,13 @@ ovsdb_idl_clear(struct ovsdb_idl *idl) } changed = true; - HMAP_FOR_EACH_SAFE (row, next_row, struct ovsdb_idl_row, hmap_node, - &table->rows) { + HMAP_FOR_EACH_SAFE (row, next_row, hmap_node, &table->rows) { struct ovsdb_idl_arc *arc, *next_arc; if (!ovsdb_idl_row_is_orphan(row)) { ovsdb_idl_row_unparse(row); } - LIST_FOR_EACH_SAFE (arc, next_arc, struct ovsdb_idl_arc, src_node, - &row->src_arcs) { + LIST_FOR_EACH_SAFE (arc, next_arc, src_node, &row->src_arcs) { free(arc); } /* No need to do anything with dst_arcs: some node has those arcs @@ -361,64 +376,113 @@ ovsdb_idl_force_reconnect(struct ovsdb_idl *idl) { jsonrpc_session_force_reconnect(idl->session); } - -static void -ovsdb_idl_set_mode(struct ovsdb_idl *idl, - const struct ovsdb_idl_column *column, - enum ovsdb_idl_mode mode) + +static unsigned char * +ovsdb_idl_get_mode(struct ovsdb_idl *idl, + const struct ovsdb_idl_column *column) { size_t i; + assert(!idl->change_seqno); + for (i = 0; i < idl->class->n_tables; i++) { const struct ovsdb_idl_table *table = &idl->tables[i]; const struct ovsdb_idl_table_class *tc = table->class; if (column >= tc->columns && column < &tc->columns[tc->n_columns]) { - unsigned char *modep = &table->modes[column - tc->columns]; - assert(*modep == OVSDB_IDL_MODE_RW || *modep == mode); - *modep = mode; - return; + return &table->modes[column - tc->columns]; } } NOT_REACHED(); } -/* By default, 'idl' replicates all of the columns in the remote database, and - * ovsdb_idl_run() returns true upon a change to any column in the database. - * Call this function to avoid alerting ovsdb_idl_run()'s caller upon changes - * to 'column'. +static void +add_ref_table(struct ovsdb_idl *idl, const struct ovsdb_base_type *base) +{ + if (base->type == OVSDB_TYPE_UUID && base->u.uuid.refTableName) { + struct ovsdb_idl_table *table; + + table = shash_find_data(&idl->table_by_name, + base->u.uuid.refTableName); + if (table) { + table->need_table = true; + } else { + VLOG_WARN("%s IDL class missing referenced table %s", + idl->class->database, base->u.uuid.refTableName); + } + } +} + +/* Turns on OVSDB_IDL_MONITOR and OVSDB_IDL_ALERT for 'column' in 'idl'. Also + * ensures that any tables referenced by 'column' will be replicated, even if + * no columns in that table are selected for replication (see + * ovsdb_idl_add_table() for more information). * - * This is useful for columns that a client treats as "write-only", that is, it - * updates them but doesn't want to get alerted about its own updates. It also - * won't be alerted about other clients' updates, so this is suitable only for - * use by a client that "owns" a particular column. + * This function is only useful if 'monitor_everything_by_default' was false in + * the call to ovsdb_idl_create(). This function should be called between + * ovsdb_idl_create() and the first call to ovsdb_idl_run(). + */ +void +ovsdb_idl_add_column(struct ovsdb_idl *idl, + const struct ovsdb_idl_column *column) +{ + *ovsdb_idl_get_mode(idl, column) = OVSDB_IDL_MONITOR | OVSDB_IDL_ALERT; + add_ref_table(idl, &column->type.key); + add_ref_table(idl, &column->type.value); +} + +/* Ensures that the table with class 'tc' will be replicated on 'idl' even if + * no columns are selected for replication. This can be useful because it + * allows 'idl' to keep track of what rows in the table actually exist, which + * in turn allows columns that reference the table to have accurate contents. + * (The IDL presents the database with references to rows that do not exist + * removed.) * - * The client must be careful not to retain pointers to data in 'column' across - * calls to ovsdb_idl_run(), even when that function returns false, because - * the client is not alerted to changes. + * This function is only useful if 'monitor_everything_by_default' was false in + * the call to ovsdb_idl_create(). This function should be called between + * ovsdb_idl_create() and the first call to ovsdb_idl_run(). + */ +void +ovsdb_idl_add_table(struct ovsdb_idl *idl, + const struct ovsdb_idl_table_class *tc) +{ + size_t i; + + for (i = 0; i < idl->class->n_tables; i++) { + struct ovsdb_idl_table *table = &idl->tables[i]; + + if (table->class == tc) { + table->need_table = true; + return; + } + } + + NOT_REACHED(); +} + +/* Turns off OVSDB_IDL_ALERT for 'column' in 'idl'. * - * This function should be called after ovsdb_idl_create(), but before the - * first call to ovsdb_idl_run(). For any given column, this function may be - * called or ovsdb_idl_omit() may be called, but not both. */ + * This function should be called between ovsdb_idl_create() and the first call + * to ovsdb_idl_run(). + */ void -ovsdb_idl_set_write_only(struct ovsdb_idl *idl, - const struct ovsdb_idl_column *column) +ovsdb_idl_omit_alert(struct ovsdb_idl *idl, + const struct ovsdb_idl_column *column) { - ovsdb_idl_set_mode(idl, column, OVSDB_IDL_MODE_WO); + *ovsdb_idl_get_mode(idl, column) &= ~OVSDB_IDL_ALERT; } -/* By default, 'idl' replicates all of the columns in the remote database. - * Call this function to omit replicating 'column'. This saves CPU time and - * bandwidth to the database. +/* Sets the mode for 'column' in 'idl' to 0. See the big comment above + * OVSDB_IDL_MONITOR for details. * - * This function should be called after ovsdb_idl_create(), but before the - * first call to ovsdb_idl_run(). For any given column, this function may be - * called or ovsdb_idl_set_write_only() may be called, but not both. */ + * This function should be called between ovsdb_idl_create() and the first call + * to ovsdb_idl_run(). + */ void ovsdb_idl_omit(struct ovsdb_idl *idl, const struct ovsdb_idl_column *column) { - ovsdb_idl_set_mode(idl, column, OVSDB_IDL_MODE_NONE); + *ovsdb_idl_get_mode(idl, column) = 0; } static void @@ -433,18 +497,24 @@ ovsdb_idl_send_monitor_request(struct ovsdb_idl *idl) const struct ovsdb_idl_table *table = &idl->tables[i]; const struct ovsdb_idl_table_class *tc = table->class; struct json *monitor_request, *columns; - size_t i; + size_t j; - monitor_request = json_object_create(); - columns = json_array_create_empty(); - for (i = 0; i < tc->n_columns; i++) { - const struct ovsdb_idl_column *column = &tc->columns[i]; - if (table->modes[i] != OVSDB_IDL_MODE_NONE) { + columns = table->need_table ? json_array_create_empty() : NULL; + for (j = 0; j < tc->n_columns; j++) { + const struct ovsdb_idl_column *column = &tc->columns[j]; + if (table->modes[j] & OVSDB_IDL_MONITOR) { + if (!columns) { + columns = json_array_create_empty(); + } json_array_add(columns, json_string_create(column->name)); } } - json_object_put(monitor_request, "columns", columns); - json_object_put(monitor_requests, tc->name, monitor_request); + + if (columns) { + monitor_request = json_object_create(); + json_object_put(monitor_request, "columns", columns); + json_object_put(monitor_requests, tc->name, monitor_request); + } } json_destroy(idl->monitor_request_id); @@ -553,8 +623,7 @@ ovsdb_idl_get_row(struct ovsdb_idl_table *table, const struct uuid *uuid) { struct ovsdb_idl_row *row; - HMAP_FOR_EACH_WITH_HASH (row, struct ovsdb_idl_row, hmap_node, - uuid_hash(uuid), &table->rows) { + HMAP_FOR_EACH_WITH_HASH (row, hmap_node, uuid_hash(uuid), &table->rows) { if (uuid_equals(&row->uuid, uuid)) { return row; } @@ -645,7 +714,7 @@ ovsdb_idl_row_update(struct ovsdb_idl_row *row, const struct json *row_json) if (!ovsdb_datum_equals(old, &datum, &column->type)) { ovsdb_datum_swap(old, &datum); - if (table->modes[column_idx] == OVSDB_IDL_MODE_RW) { + if (table->modes[column_idx] & OVSDB_IDL_ALERT) { changed = true; } } else { @@ -771,8 +840,7 @@ ovsdb_idl_row_clear_arcs(struct ovsdb_idl_row *row, bool destroy_dsts) /* Delete all forward arcs. If 'destroy_dsts', destroy any orphaned rows * that this causes to be unreferenced. */ - LIST_FOR_EACH_SAFE (arc, next, struct ovsdb_idl_arc, src_node, - &row->src_arcs) { + LIST_FOR_EACH_SAFE (arc, next, src_node, &row->src_arcs) { list_remove(&arc->dst_node); if (destroy_dsts && ovsdb_idl_row_is_orphan(arc->dst) @@ -800,8 +868,7 @@ ovsdb_idl_row_reparse_backrefs(struct ovsdb_idl_row *row) * (If duplicate arcs were possible then we would need to make sure that * 'next' didn't also point into 'arc''s destination, but we forbid * duplicate arcs.) */ - LIST_FOR_EACH_SAFE (arc, next, struct ovsdb_idl_arc, dst_node, - &row->dst_arcs) { + LIST_FOR_EACH_SAFE (arc, next, dst_node, &row->dst_arcs) { struct ovsdb_idl_row *ref = arc->src; ovsdb_idl_row_unparse(ref); @@ -1145,8 +1212,7 @@ ovsdb_idl_txn_destroy(struct ovsdb_idl_txn *txn) free(txn->inc_table); free(txn->inc_column); json_destroy(txn->inc_where); - HMAP_FOR_EACH_SAFE (insert, next, struct ovsdb_idl_txn_insert, hmap_node, - &txn->inserted_rows) { + HMAP_FOR_EACH_SAFE (insert, next, hmap_node, &txn->inserted_rows) { free(insert); } hmap_destroy(&txn->inserted_rows); @@ -1196,8 +1262,7 @@ ovsdb_idl_txn_get_row(const struct ovsdb_idl_txn *txn, const struct uuid *uuid) { const struct ovsdb_idl_row *row; - HMAP_FOR_EACH_WITH_HASH (row, struct ovsdb_idl_row, txn_node, - uuid_hash(uuid), &txn->txn_rows) { + HMAP_FOR_EACH_WITH_HASH (row, txn_node, uuid_hash(uuid), &txn->txn_rows) { if (uuid_equals(&row->uuid, uuid)) { return row; } @@ -1255,8 +1320,7 @@ ovsdb_idl_txn_disassemble(struct ovsdb_idl_txn *txn) * transaction and fail to update the graph. */ txn->idl->txn = NULL; - HMAP_FOR_EACH_SAFE (row, next, struct ovsdb_idl_row, txn_node, - &txn->txn_rows) { + HMAP_FOR_EACH_SAFE (row, next, txn_node, &txn->txn_rows) { if (row->old) { if (row->written) { ovsdb_idl_row_unparse(row); @@ -1300,7 +1364,7 @@ ovsdb_idl_txn_commit(struct ovsdb_idl_txn *txn) json_string_create(txn->idl->class->database)); /* Add prerequisites and declarations of new rows. */ - HMAP_FOR_EACH (row, struct ovsdb_idl_row, txn_node, &txn->txn_rows) { + HMAP_FOR_EACH (row, txn_node, &txn->txn_rows) { /* XXX check that deleted rows exist even if no prereqs? */ if (row->prereqs) { const struct ovsdb_idl_table_class *class = row->table->class; @@ -1332,7 +1396,7 @@ ovsdb_idl_txn_commit(struct ovsdb_idl_txn *txn) /* Add updates. */ any_updates = false; - HMAP_FOR_EACH (row, struct ovsdb_idl_row, txn_node, &txn->txn_rows) { + HMAP_FOR_EACH (row, txn_node, &txn->txn_rows) { const struct ovsdb_idl_table_class *class = row->table->class; if (row->old == row->new) { @@ -1530,7 +1594,7 @@ ovsdb_idl_txn_get_insert_uuid(const struct ovsdb_idl_txn *txn, const struct ovsdb_idl_txn_insert *insert; assert(txn->status == TXN_SUCCESS || txn->status == TXN_UNCHANGED); - HMAP_FOR_EACH_IN_BUCKET (insert, struct ovsdb_idl_txn_insert, hmap_node, + HMAP_FOR_EACH_IN_BUCKET (insert, hmap_node, uuid_hash(uuid), &txn->inserted_rows) { if (uuid_equals(uuid, &insert->dummy)) { return &insert->real; @@ -1547,6 +1611,19 @@ ovsdb_idl_txn_complete(struct ovsdb_idl_txn *txn, hmap_remove(&txn->idl->outstanding_txns, &txn->hmap_node); } +/* Writes 'datum' to the specified 'column' in 'row_'. Updates both 'row_' + * itself and the structs derived from it (e.g. the "struct ovsrec_*", for + * ovs-vswitchd). + * + * 'datum' must have the correct type for its column. The IDL does not check + * that it meets schema constraints, but ovsdb-server will do so at commit time + * so it had better be correct. + * + * A transaction must be in progress. Replication of 'column' must not have + * been disabled (by calling ovsdb_idl_omit()). + * + * Usually this function is used indirectly through one of the "set" functions + * generated by ovsdb-idlc. */ void ovsdb_idl_txn_write(const struct ovsdb_idl_row *row_, const struct ovsdb_idl_column *column, @@ -1558,7 +1635,8 @@ ovsdb_idl_txn_write(const struct ovsdb_idl_row *row_, assert(row->new != NULL); assert(column_idx < class->n_columns); - assert(row->table->modes[column_idx] != OVSDB_IDL_MODE_NONE); + assert(row->old == NULL || + row->table->modes[column_idx] & OVSDB_IDL_MONITOR); if (hmap_node_is_null(&row->txn_node)) { hmap_insert(&row->table->idl->txn->txn_rows, &row->txn_node, @@ -1580,6 +1658,32 @@ ovsdb_idl_txn_write(const struct ovsdb_idl_row *row_, (column->parse)(row, &row->new[column_idx]); } +/* Causes the original contents of 'column' in 'row_' to be verified as a + * prerequisite to completing the transaction. That is, if 'column' in 'row_' + * changed (or if 'row_' was deleted) between the time that the IDL originally + * read its contents and the time that the transaction commits, then the + * transaction aborts and ovsdb_idl_txn_commit() returns TXN_TRY_AGAIN. + * + * The intention is that, to ensure that no transaction commits based on dirty + * reads, an application should call ovsdb_idl_txn_verify() on each data item + * read as part of a read-modify-write operation. + * + * In some cases ovsdb_idl_txn_verify() reduces to a no-op, because the current + * value of 'column' is already known: + * + * - If 'row_' is a row created by the current transaction (returned by + * ovsdb_idl_txn_insert()). + * + * - If 'column' has already been modified (with ovsdb_idl_txn_write()) + * within the current transaction. + * + * Because of the latter property, always call ovsdb_idl_txn_verify() *before* + * ovsdb_idl_txn_write() for a given read-modify-write. + * + * A transaction must be in progress. + * + * Usually this function is used indirectly through one of the "verify" + * functions generated by ovsdb-idlc. */ void ovsdb_idl_txn_verify(const struct ovsdb_idl_row *row_, const struct ovsdb_idl_column *column) @@ -1589,6 +1693,8 @@ ovsdb_idl_txn_verify(const struct ovsdb_idl_row *row_, size_t column_idx = column - class->columns; assert(row->new != NULL); + assert(row->old == NULL || + row->table->modes[column_idx] & OVSDB_IDL_MONITOR); if (!row->old || (row->written && bitmap_is_set(row->written, column_idx))) { return; @@ -1604,6 +1710,13 @@ ovsdb_idl_txn_verify(const struct ovsdb_idl_row *row_, bitmap_set1(row->prereqs, column_idx); } +/* Deletes 'row_' from its table. May free 'row_', so it must not be + * accessed afterward. + * + * A transaction must be in progress. + * + * Usually this function is used indirectly through one of the "delete" + * functions generated by ovsdb-idlc. */ void ovsdb_idl_txn_delete(const struct ovsdb_idl_row *row_) { @@ -1627,6 +1740,18 @@ ovsdb_idl_txn_delete(const struct ovsdb_idl_row *row_) row->new = NULL; } +/* Inserts and returns a new row in the table with the specified 'class' in the + * database with open transaction 'txn'. + * + * The new row is assigned a provisional UUID. If 'uuid' is null then one is + * randomly generated; otherwise 'uuid' should specify a randomly generated + * UUID not otherwise in use. ovsdb-server will assign a different UUID when + * 'txn' is committed, but the IDL will replace any uses of the provisional + * UUID in the data to be to be committed by the UUID assigned by + * ovsdb-server. + * + * Usually this function is used indirectly through one of the "insert" + * functions generated by ovsdb-idlc. */ const struct ovsdb_idl_row * ovsdb_idl_txn_insert(struct ovsdb_idl_txn *txn, const struct ovsdb_idl_table_class *class, @@ -1653,8 +1778,7 @@ ovsdb_idl_txn_abort_all(struct ovsdb_idl *idl) { struct ovsdb_idl_txn *txn; - HMAP_FOR_EACH (txn, struct ovsdb_idl_txn, hmap_node, - &idl->outstanding_txns) { + HMAP_FOR_EACH (txn, hmap_node, &idl->outstanding_txns) { ovsdb_idl_txn_complete(txn, TXN_TRY_AGAIN); } } @@ -1664,7 +1788,7 @@ ovsdb_idl_txn_find(struct ovsdb_idl *idl, const struct json *id) { struct ovsdb_idl_txn *txn; - HMAP_FOR_EACH_WITH_HASH (txn, struct ovsdb_idl_txn, hmap_node, + HMAP_FOR_EACH_WITH_HASH (txn, hmap_node, json_hash(id, 0), &idl->outstanding_txns) { if (json_equal(id, txn->request_id)) { return txn; @@ -1844,8 +1968,7 @@ ovsdb_idl_txn_process_reply(struct ovsdb_idl *idl, hard_errors++; } - HMAP_FOR_EACH (insert, struct ovsdb_idl_txn_insert, hmap_node, - &txn->inserted_rows) { + HMAP_FOR_EACH (insert, hmap_node, &txn->inserted_rows) { if (!ovsdb_idl_txn_process_insert_reply(insert, ops)) { hard_errors++; }