Merge remote-tracking branch 'origin/mdb.master'

This commit is contained in:
Howard Chu 2013-07-01 14:55:25 -07:00
commit 60720f5d9c

View File

@ -1743,7 +1743,6 @@ mdb_txn_renew0(MDB_txn *txn)
unsigned int i;
uint16_t x;
int rc, new_notls = 0;
pgno_t lastpg2;
/* Setup db info */
txn->mt_numdbs = env->me_numdbs;
@ -1790,13 +1789,11 @@ mdb_txn_renew0(MDB_txn *txn)
txn->mt_u.reader = r;
}
txn->mt_toggle = txn->mt_txnid & 1;
txn->mt_next_pgno = env->me_metas[txn->mt_toggle]->mm_last_pg+1;
} else {
LOCK_MUTEX_W(env);
txn->mt_txnid = env->me_txns->mti_txnid;
txn->mt_toggle = txn->mt_txnid & 1;
txn->mt_next_pgno = env->me_metas[txn->mt_toggle]->mm_last_pg+1;
txn->mt_txnid++;
#if MDB_DEBUG
if (txn->mt_txnid == mdb_debug_start)
@ -1812,17 +1809,10 @@ mdb_txn_renew0(MDB_txn *txn)
/* Copy the DB info and flags */
memcpy(txn->mt_dbs, env->me_metas[txn->mt_toggle]->mm_dbs, 2 * sizeof(MDB_db));
/* In a read txn, there is a data race here. Make sure our
* last_pg/next_pg are up to date.
*/
lastpg2 = env->me_metas[txn->mt_toggle]->mm_last_pg+1;
if (lastpg2 != txn->mt_next_pgno) {
txn->mt_next_pgno = lastpg2;
/* When this situation occurs, the txnid will certainly also
* be out of date. But as noted before, we don't care about having
* up to date read txn IDs.
*/
}
/* Moved to here to avoid a data race in read TXNs */
txn->mt_next_pgno = env->me_metas[txn->mt_toggle]->mm_last_pg+1;
for (i=2; i<txn->mt_numdbs; i++) {
x = env->me_dbflags[i];
txn->mt_dbs[i].md_flags = x & PERSISTENT_FLAGS;