From 5bdf2aae6ee0c8bdcd6a7759bd098d6531c668a0 Mon Sep 17 00:00:00 2001 From: Hallvard Furuseth Date: Mon, 20 May 2013 23:12:26 +0200 Subject: [PATCH] Tweak mdb_page_malloc(),mdb_page_get() semantics. mdb_page_malloc(): Add "number of pages" parameter. mdb_page_get(): Add output param for how page was found. Do not set return params on error. mdb_cursor_put(): Catch mdb_page_get() error. Prepares for next commit, no change in caller behavior other than on mdb_page_get error. --- libraries/liblmdb/mdb.c | 89 +++++++++++++++++++++++------------------ 1 file changed, 50 insertions(+), 39 deletions(-) diff --git a/libraries/liblmdb/mdb.c b/libraries/liblmdb/mdb.c index 79635fd014..6c7d28c6b9 100644 --- a/libraries/liblmdb/mdb.c +++ b/libraries/liblmdb/mdb.c @@ -999,7 +999,7 @@ static int mdb_page_alloc(MDB_cursor *mc, int num, MDB_page **mp); static int mdb_page_new(MDB_cursor *mc, uint32_t flags, int num, MDB_page **mp); static int mdb_page_touch(MDB_cursor *mc); -static int mdb_page_get(MDB_txn *txn, pgno_t pgno, MDB_page **mp); +static int mdb_page_get(MDB_txn *txn, pgno_t pgno, MDB_page **mp, int *lvl); static int mdb_page_search_root(MDB_cursor *mc, MDB_val *key, int modify); #define MDB_PS_MODIFY 1 @@ -1252,19 +1252,27 @@ mdb_dcmp(MDB_txn *txn, MDB_dbi dbi, const MDB_val *a, const MDB_val *b) return txn->mt_dbxs[dbi].md_dcmp(a, b); } -/** Allocate a single page. - * Re-use old malloc'd pages first, otherwise just malloc. +/** Allocate a page. + * Re-use old malloc'd pages first for singletons, otherwise just malloc. */ static MDB_page * -mdb_page_malloc(MDB_cursor *mc) { - MDB_page *ret; - size_t sz = mc->mc_txn->mt_env->me_psize; - if ((ret = mc->mc_txn->mt_env->me_dpages) != NULL) { - VGMEMP_ALLOC(mc->mc_txn->mt_env, ret, sz); - VGMEMP_DEFINED(ret, sizeof(ret->mp_next)); - mc->mc_txn->mt_env->me_dpages = ret->mp_next; - } else if ((ret = malloc(sz)) != NULL) { - VGMEMP_ALLOC(mc->mc_txn->mt_env, ret, sz); +mdb_page_malloc(MDB_cursor *mc, unsigned num) +{ + MDB_env *env = mc->mc_txn->mt_env; + MDB_page *ret = env->me_dpages; + size_t sz = env->me_psize; + if (num == 1) { + if (ret) { + VGMEMP_ALLOC(env, ret, sz); + VGMEMP_DEFINED(ret, sizeof(ret->mp_next)); + env->me_dpages = ret->mp_next; + return ret; + } + } else { + sz *= num; + } + if ((ret = malloc(sz)) != NULL) { + VGMEMP_ALLOC(env, ret, sz); } return ret; } @@ -1520,17 +1528,8 @@ none: np = (MDB_page *)(txn->mt_env->me_map + txn->mt_env->me_psize * pgno); np->mp_pgno = pgno; } else { - if (txn->mt_env->me_dpages && num == 1) { - np = txn->mt_env->me_dpages; - VGMEMP_ALLOC(txn->mt_env, np, txn->mt_env->me_psize); - VGMEMP_DEFINED(np, sizeof(np->mp_next)); - txn->mt_env->me_dpages = np->mp_next; - } else { - size_t sz = txn->mt_env->me_psize * num; - if ((np = malloc(sz)) == NULL) - return ENOMEM; - VGMEMP_ALLOC(txn->mt_env, np, sz); - } + if (!(np = mdb_page_malloc(mc, num))) + return ENOMEM; if (pgno == P_INVALID) { np->mp_pgno = txn->mt_next_pgno; txn->mt_next_pgno += num; @@ -1653,7 +1652,7 @@ finish: } assert(mc->mc_txn->mt_u.dirty_list[0].mid < MDB_IDL_UM_MAX); /* No - copy it */ - np = mdb_page_malloc(mc); + np = mdb_page_malloc(mc, 1); if (!np) return ENOMEM; memcpy(np, mp, mc->mc_txn->mt_env->me_psize); @@ -4032,17 +4031,20 @@ mdb_cursor_push(MDB_cursor *mc, MDB_page *mp) * @param[in] txn the transaction for this access. * @param[in] pgno the page number for the page to retrieve. * @param[out] ret address of a pointer where the page's address will be stored. + * @param[out] lvl dirty_list inheritance level of found page. 1=current txn, 0=mapped page. * @return 0 on success, non-zero on failure. */ static int -mdb_page_get(MDB_txn *txn, pgno_t pgno, MDB_page **ret) +mdb_page_get(MDB_txn *txn, pgno_t pgno, MDB_page **ret, int *lvl) { MDB_page *p = NULL; + int level; if (!((txn->mt_flags & MDB_TXN_RDONLY) | (txn->mt_env->me_flags & MDB_WRITEMAP))) { MDB_txn *tx2 = txn; + level = 1; do { MDB_ID2L dl = tx2->mt_u.dirty_list; if (dl[0].mid) { @@ -4052,19 +4054,24 @@ mdb_page_get(MDB_txn *txn, pgno_t pgno, MDB_page **ret) goto done; } } + level++; } while ((tx2 = tx2->mt_parent) != NULL); } if (pgno < txn->mt_next_pgno) { + level = 0; p = (MDB_page *)(txn->mt_env->me_map + txn->mt_env->me_psize * pgno); } else { DPRINTF("page %zu not found", pgno); assert(p != NULL); + return MDB_PAGE_NOTFOUND; } done: *ret = p; - return (p != NULL) ? MDB_SUCCESS : MDB_PAGE_NOTFOUND; + if (lvl) + *lvl = level; + return MDB_SUCCESS; } /** Search for the page a given key should be in. @@ -4118,7 +4125,7 @@ mdb_page_search_root(MDB_cursor *mc, MDB_val *key, int modify) assert(i < NUMKEYS(mp)); node = NODEPTR(mp, i); - if ((rc = mdb_page_get(mc->mc_txn, NODEPGNO(node), &mp))) + if ((rc = mdb_page_get(mc->mc_txn, NODEPGNO(node), &mp, NULL)) != 0) return rc; mc->mc_ki[mc->mc_top] = i; @@ -4157,7 +4164,7 @@ mdb_page_search_lowest(MDB_cursor *mc) MDB_node *node = NODEPTR(mp, 0); int rc; - if ((rc = mdb_page_get(mc->mc_txn, NODEPGNO(node), &mp))) + if ((rc = mdb_page_get(mc->mc_txn, NODEPGNO(node), &mp, NULL)) != 0) return rc; mc->mc_ki[mc->mc_top] = 0; @@ -4235,7 +4242,7 @@ mdb_page_search(MDB_cursor *mc, MDB_val *key, int flags) assert(root > 1); if (!mc->mc_pg[0] || mc->mc_pg[0]->mp_pgno != root) - if ((rc = mdb_page_get(mc->mc_txn, root, &mc->mc_pg[0]))) + if ((rc = mdb_page_get(mc->mc_txn, root, &mc->mc_pg[0], NULL)) != 0) return rc; mc->mc_snum = 1; @@ -4278,7 +4285,7 @@ mdb_node_read(MDB_txn *txn, MDB_node *leaf, MDB_val *data) */ data->mv_size = NODEDSZ(leaf); memcpy(&pgno, NODEDATA(leaf), sizeof(pgno)); - if ((rc = mdb_page_get(txn, pgno, &omp))) { + if ((rc = mdb_page_get(txn, pgno, &omp, NULL)) != 0) { DPRINTF("read overflow page %zu failed", pgno); return rc; } @@ -4355,7 +4362,7 @@ mdb_cursor_sibling(MDB_cursor *mc, int move_right) assert(IS_BRANCH(mc->mc_pg[mc->mc_top])); indx = NODEPTR(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top]); - if ((rc = mdb_page_get(mc->mc_txn, NODEPGNO(indx), &mp))) + if ((rc = mdb_page_get(mc->mc_txn, NODEPGNO(indx), &mp, NULL) != 0)) return rc; mdb_cursor_push(mc, mp); @@ -5194,7 +5201,8 @@ current: dpages = OVPAGES(data->mv_size, mc->mc_txn->mt_env->me_psize); memcpy(&pg, NODEDATA(leaf), sizeof(pg)); - mdb_page_get(mc->mc_txn, pg, &omp); + if ((rc2 = mdb_page_get(mc->mc_txn, pg, &omp, NULL)) != 0) + return rc2; ovpages = omp->mp_pages; /* Is the ov page writable and large enough? */ @@ -6415,8 +6423,8 @@ mdb_rebalance(MDB_cursor *mc) DPUTS("collapsing root page!"); mdb_midl_append(&mc->mc_txn->mt_free_pgs, mp->mp_pgno); mc->mc_db->md_root = NODEPGNO(NODEPTR(mp, 0)); - if ((rc = mdb_page_get(mc->mc_txn, mc->mc_db->md_root, - &mc->mc_pg[0]))) + rc = mdb_page_get(mc->mc_txn,mc->mc_db->md_root,&mc->mc_pg[0],NULL); + if (rc) return rc; mc->mc_db->md_depth--; mc->mc_db->md_branch_pages--; @@ -6469,7 +6477,8 @@ mdb_rebalance(MDB_cursor *mc) DPUTS("reading right neighbor"); mn.mc_ki[ptop]++; node = NODEPTR(mc->mc_pg[ptop], mn.mc_ki[ptop]); - if ((rc = mdb_page_get(mc->mc_txn, NODEPGNO(node), &mn.mc_pg[mn.mc_top]))) + rc = mdb_page_get(mc->mc_txn,NODEPGNO(node),&mn.mc_pg[mn.mc_top],NULL); + if (rc) return rc; mn.mc_ki[mn.mc_top] = 0; mc->mc_ki[mc->mc_top] = NUMKEYS(mc->mc_pg[mc->mc_top]); @@ -6479,7 +6488,8 @@ mdb_rebalance(MDB_cursor *mc) DPUTS("reading left neighbor"); mn.mc_ki[ptop]--; node = NODEPTR(mc->mc_pg[ptop], mn.mc_ki[ptop]); - if ((rc = mdb_page_get(mc->mc_txn, NODEPGNO(node), &mn.mc_pg[mn.mc_top]))) + rc = mdb_page_get(mc->mc_txn,NODEPGNO(node),&mn.mc_pg[mn.mc_top],NULL); + if (rc) return rc; mn.mc_ki[mn.mc_top] = NUMKEYS(mn.mc_pg[mn.mc_top]) - 1; mc->mc_ki[mc->mc_top] = 0; @@ -6518,7 +6528,7 @@ mdb_cursor_del0(MDB_cursor *mc, MDB_node *leaf) pgno_t pg; memcpy(&pg, NODEDATA(leaf), sizeof(pg)); - if ((rc = mdb_page_get(mc->mc_txn, pg, &omp)) != 0) + if ((rc = mdb_page_get(mc->mc_txn, pg, &omp, NULL)) != 0) return rc; assert(IS_OVERFLOW(omp)); ovpages = omp->mp_pages; @@ -6863,7 +6873,7 @@ newsep: /* Move half of the keys to the right sibling. */ /* grab a page to hold a temporary copy */ - copy = mdb_page_malloc(mc); + copy = mdb_page_malloc(mc, 1); if (copy == NULL) return ENOMEM; @@ -7287,7 +7297,8 @@ mdb_drop0(MDB_cursor *mc, int subs) MDB_page *omp; pgno_t pg; memcpy(&pg, NODEDATA(ni), sizeof(pg)); - if ((rc = mdb_page_get(mc->mc_txn, pg, &omp)) != 0) + rc = mdb_page_get(mc->mc_txn, pg, &omp, NULL); + if (rc != 0) return rc; assert(IS_OVERFLOW(omp)); ovpages = omp->mp_pages; -- 2.39.5