More for mdb_page_loose

Require that the page is dirty in the current txn,
not a parent txn.

diff --git a/libraries/liblmdb/mdb.c b/libraries/liblmdb/mdb.c
index c98247c2b9937afd26a15fa592a53a9ec14d5bbc..c21f556e08e249a5a1e2122108e6cc17f20cf9bb 100644 (file)
--- a/libraries/liblmdb/mdb.c
+++ b/libraries/liblmdb/mdb.c
@@ -899,6 +899,10 @@ struct MDB_txn {
        /** The list of pages that became unused during this transaction.
         */
        MDB_IDL         mt_free_pgs;
+       /** The list of loose pages that became unused and may be reused
+        *      in this transaction.
+        */
+       MDB_page        *mt_loose_pgs;
        /** The sorted list of dirty pages we temporarily wrote to disk
         *      because the dirty list was full. page numbers in here are
         *      shifted left by 1, deleted slots have the LSB set.
@@ -1022,7 +1026,6 @@ typedef struct MDB_xcursor {
 typedef struct MDB_pgstate {
        pgno_t          *mf_pghead;     /**< Reclaimed freeDB pages, or NULL before use */
        txnid_t         mf_pglast;      /**< ID of last used record, or 0 if !mf_pghead */
-       MDB_page        *mf_pgloose;    /**< Dirty pages that can be reused */
 } MDB_pgstate;
 
        /** The database environment. */
@@ -1059,7 +1062,6 @@ struct MDB_env {
        MDB_pgstate     me_pgstate;             /**< state of old pages from freeDB */
 #      define          me_pglast       me_pgstate.mf_pglast
 #      define          me_pghead       me_pgstate.mf_pghead
-#      define          me_pgloose      me_pgstate.mf_pgloose
        MDB_page        *me_dpages;             /**< list of malloc'd blocks for re-use */
        /** IDL of pages that became unused in a write txn */
        MDB_IDL         me_free_pgs;
@@ -1527,21 +1529,58 @@ mdb_dlist_free(MDB_txn *txn)
        dl[0].mid = 0;
 }
 
-/** Loosen a single page.
+/** Loosen or free a single page.
  * Saves single pages to a list for future reuse
  * in this same txn. It has been pulled from the freeDB
  * and already resides on the dirty list, but has been
  * deleted. Use these pages first before pulling again
  * from the freeDB.
+ *
+ * If the page wasn't dirtied in this txn, just add it
+ * to this txn's free list.
  */
-static void
-mdb_page_loose(MDB_env *env, MDB_page *mp)
+static int
+mdb_page_loose(MDB_cursor *mc, MDB_page *mp)
 {
+       int loose = 0;
+       pgno_t pgno = mp->mp_pgno;
+
+       if ((mp->mp_flags & P_DIRTY) && mc->mc_dbi != FREE_DBI) {
+               if (mc->mc_txn->mt_parent) {
+                       MDB_ID2 *dl = mc->mc_txn->mt_u.dirty_list;
+                       /* If txn has a parent, make sure the page is in our
+                        * dirty list.
+                        */
+                       if (dl[0].mid) {
+                               unsigned x = mdb_mid2l_search(dl, pgno);
+                               if (x <= dl[0].mid && dl[x].mid == pgno) {
+                                       if (mp != dl[x].mptr) { /* bad cursor? */
+                                               mc->mc_flags &= ~(C_INITIALIZED|C_EOF);
+                                               mc->mc_txn->mt_flags |= MDB_TXN_ERROR;
+                                               return MDB_CORRUPTED;
+                                       }
+                                       /* ok, it's ours */
+                                       loose = 1;
+                               }
+                       }
+               } else {
+                       /* no parent txn, so it's just ours */
+                       loose = 1;
+               }
+       }
+       if (loose) {
                pgno_t *pp = (pgno_t *)mp->mp_ptrs;
-               *pp = mp->mp_pgno;
-               mp->mp_next = env->me_pgloose;
-               env->me_pgloose = mp;
+               *pp = pgno;
+               mp->mp_next = mc->mc_txn->mt_loose_pgs;
+               mc->mc_txn->mt_loose_pgs = mp;
                mp->mp_flags |= P_LOOSE;
+       } else {
+               int rc = mdb_midl_append(&mc->mc_txn->mt_free_pgs, pgno);
+               if (rc)
+                       return rc;
+       }
+
+       return MDB_SUCCESS;
 }
 
 /** Set or clear P_KEEP in dirty, non-overflow, non-sub pages watched by txn.
@@ -1593,7 +1632,7 @@ mdb_pages_xkeep(MDB_cursor *mc, unsigned pflags, int all)
        }
 
        /* Loose pages shouldn't be spilled */
-       for (dp = txn->mt_env->me_pgloose; dp; dp=dp->mp_next) {
+       for (dp = txn->mt_loose_pgs; dp; dp=dp->mp_next) {
                if ((dp->mp_flags & Mask) == pflags)
                        dp->mp_flags ^= P_KEEP;
        }
@@ -1826,10 +1865,10 @@ mdb_page_alloc(MDB_cursor *mc, int num, MDB_page **mp)
        MDB_cursor m2;
 
        /* If there are any loose pages, just use them */
-       if (num == 1 && env->me_pgloose) {
+       if (num == 1 && txn->mt_loose_pgs) {
                pgno_t *pp;
-               np = env->me_pgloose;
-               env->me_pgloose = np->mp_next;
+               np = txn->mt_loose_pgs;
+               txn->mt_loose_pgs = np->mp_next;
                pp = (pgno_t *)np->mp_ptrs;
                np->mp_pgno = *pp;
                *mp = np;
@@ -2700,8 +2739,8 @@ mdb_freelist_save(MDB_txn *txn)
        /* Dispose of loose pages. Usually they will have all
         * been used up by the time we get here.
         */
-       if (env->me_pgloose) {
-               MDB_page *mp = env->me_pgloose;
+       if (txn->mt_loose_pgs) {
+               MDB_page *mp = txn->mt_loose_pgs;
                pgno_t *pp;
                /* Just return them to freeDB */
                if (env->me_pghead) {
@@ -2726,7 +2765,7 @@ mdb_freelist_save(MDB_txn *txn)
                                mp = mp->mp_next;
                        }
                }
-               env->me_pgloose = NULL;
+               txn->mt_loose_pgs = NULL;
        }
 
        /* MDB_RESERVE cancels meminit in ovpage malloc (when no WRITEMAP) */
@@ -7343,15 +7382,11 @@ mdb_page_merge(MDB_cursor *csrc, MDB_cursor *cdst)
 
        psrc = csrc->mc_pg[csrc->mc_top];
        /* If not operating on FreeDB, allow this page to be reused
-        * in this txn.
+        * in this txn. Otherwise just add to free list.
         */
-       if ((psrc->mp_flags & P_DIRTY) && csrc->mc_dbi != FREE_DBI) {
-               mdb_page_loose(csrc->mc_txn->mt_env, psrc);
-       } else {
-               rc = mdb_midl_append(&csrc->mc_txn->mt_free_pgs, psrc->mp_pgno);
-               if (rc)
-                       return rc;
-       }
+       rc = mdb_page_loose(csrc, psrc);
+       if (rc)
+               return rc;
        if (IS_LEAF(psrc))
                csrc->mc_db->md_leaf_pages--;
        else