From c324b10f288a3bf3dfc8789b108d2daa53cf769a Mon Sep 17 00:00:00 2001 From: "G. Paul Ziemba" Date: Tue, 21 Sep 2021 07:34:20 -0700 Subject: [PATCH] lib: skiplist: clean up level counter implementation Signed-off-by: G. Paul Ziemba --- lib/skiplist.c | 43 ++++++------ lib/skiplist.h | 3 +- tests/lib/test_skiplist.c | 135 ++++++++++++++++++++++++++++++++++++++ tests/subdir.am | 5 ++ 4 files changed, 166 insertions(+), 20 deletions(-) create mode 100644 tests/lib/test_skiplist.c diff --git a/lib/skiplist.c b/lib/skiplist.c index fc42857418..c5219f7381 100644 --- a/lib/skiplist.c +++ b/lib/skiplist.c @@ -65,17 +65,25 @@ DEFINE_MTYPE_STATIC(LIB, SKIP_LIST, "Skip List"); DEFINE_MTYPE_STATIC(LIB, SKIP_LIST_NODE, "Skip Node"); +DEFINE_MTYPE_STATIC(LIB, SKIP_LIST_STATS, "Skiplist Counters"); #define BitsInRandom 31 #define MaxNumberOfLevels 16 #define MaxLevel (MaxNumberOfLevels-1) -#define newNodeOfLevel(l) XCALLOC(MTYPE_SKIP_LIST_NODE, sizeof(struct skiplistnode)+(l)*sizeof(struct skiplistnode *)) +#define newNodeOfLevel(l) \ + XCALLOC(MTYPE_SKIP_LIST_NODE, \ + sizeof(struct skiplistnode) \ + + (l) * sizeof(struct skiplistnode *)) + +/* XXX must match type of (struct skiplist).level_stats */ +#define newStatsOfLevel(l) \ + XCALLOC(MTYPE_SKIP_LIST_STATS, ((l) + 1) * sizeof(int)) static int randomsLeft; static int randomBits; -#if 1 +#ifdef SKIPLIST_DEBUG #define CHECKLAST(sl) \ do { \ if ((sl)->header->forward[0] && !(sl)->last) \ @@ -138,7 +146,7 @@ struct skiplist *skiplist_new(int flags, new->level = 0; new->count = 0; new->header = newNodeOfLevel(MaxNumberOfLevels); - new->stats = newNodeOfLevel(MaxNumberOfLevels); + new->level_stats = newStatsOfLevel(MaxNumberOfLevels); new->flags = flags; if (cmp) @@ -166,7 +174,7 @@ void skiplist_free(struct skiplist *l) p = q; } while (p); - XFREE(MTYPE_SKIP_LIST_NODE, l->stats); + XFREE(MTYPE_SKIP_LIST_STATS, l->level_stats); XFREE(MTYPE_SKIP_LIST, l); } @@ -180,11 +188,13 @@ int skiplist_insert(register struct skiplist *l, register void *key, CHECKLAST(l); +#ifdef SKIPLIST_DEBUG /* DEBUG */ if (!key) { flog_err(EC_LIB_DEVELOPMENT, "%s: key is 0, value is %p", __func__, value); } +#endif p = l->header; k = l->level; @@ -214,10 +224,10 @@ int skiplist_insert(register struct skiplist *l, register void *key, q->flags = SKIPLIST_NODE_FLAG_INSERTED; /* debug */ #endif - ++(l->stats->forward[k]); + ++(l->level_stats[k]); #ifdef SKIPLIST_DEBUG - zlog_debug("%s: incremented stats @%p:%d, now %ld", __func__, l, k, - l->stats->forward[k] - (struct skiplistnode *)NULL); + zlog_debug("%s: incremented level_stats @%p:%d, now %d", __func__, l, k, + l->level_stats[k]); #endif do { @@ -298,12 +308,10 @@ int skiplist_delete(register struct skiplist *l, register void *key, k++) { p->forward[k] = q->forward[k]; } - --(l->stats->forward[k - 1]); + --(l->level_stats[k - 1]); #ifdef SKIPLIST_DEBUG - zlog_debug("%s: decremented stats @%p:%d, now %ld", - __func__, l, k - 1, - l->stats->forward[k - 1] - - (struct skiplistnode *)NULL); + zlog_debug("%s: decremented level_stats @%p:%d, now %d", + __func__, l, k - 1, l->level_stats[k - 1]); #endif if (l->del) (*l->del)(q->value); @@ -559,11 +567,10 @@ int skiplist_delete_first(register struct skiplist *l) l->last = NULL; } - --(l->stats->forward[nodelevel]); + --(l->level_stats[nodelevel]); #ifdef SKIPLIST_DEBUG - zlog_debug("%s: decremented stats @%p:%d, now %ld", __func__, l, - nodelevel, - l->stats->forward[nodelevel] - (struct skiplistnode *)NULL); + zlog_debug("%s: decremented level_stats @%p:%d, now %d", __func__, l, + nodelevel, l->level_stats[nodelevel]); #endif if (l->del) @@ -587,9 +594,7 @@ void skiplist_debug(struct vty *vty, struct skiplist *l) vty_out(vty, "Skiplist %p has max level %d\n", l, l->level); for (i = l->level; i >= 0; --i) - vty_out(vty, " @%d: %ld\n", i, - (long)((l->stats->forward[i]) - - (struct skiplistnode *)NULL)); + vty_out(vty, " @%d: %d\n", i, l->level_stats[i]); } static void *scramble(int i) diff --git a/lib/skiplist.h b/lib/skiplist.h index a106a455d6..00950e13bb 100644 --- a/lib/skiplist.h +++ b/lib/skiplist.h @@ -60,7 +60,7 @@ struct skiplist { int level; /* max lvl (1 + current # of levels in list) */ unsigned int count; struct skiplistnode *header; - struct skiplistnode *stats; + int *level_stats; struct skiplistnode *last; /* last real list item (NULL if empty list) */ @@ -123,6 +123,7 @@ extern int skiplist_empty(register struct skiplist *l); /* in */ extern unsigned int skiplist_count(register struct skiplist *l); /* in */ +struct vty; extern void skiplist_debug(struct vty *vty, struct skiplist *l); extern void skiplist_test(struct vty *vty); diff --git a/tests/lib/test_skiplist.c b/tests/lib/test_skiplist.c new file mode 100644 index 0000000000..2f9ca5eaea --- /dev/null +++ b/tests/lib/test_skiplist.c @@ -0,0 +1,135 @@ +/* + * Copyright (c) 2021, LabN Consulting, L.L.C + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the Free + * Software Foundation; either version 2 of the License, or (at your option) + * any later version. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; see the file COPYING; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include +#include + +static void sl_debug(struct skiplist *l) +{ + int i; + + if (!l) + return; + + printf("Skiplist %p has max level %d\n", l, l->level); + for (i = l->level; i >= 0; --i) + printf(" @%d: %d\n", i, l->level_stats[i]); +} + +static void *scramble(int i) +{ + uintptr_t result; + + result = (uintptr_t)(i & 0xff) << 24; + result |= (uintptr_t)i >> 8; + + return (void *)result; +} +#define sampleSize 65536 +static int sl_test(void) +{ + struct skiplist *l; + register int i, k; + void *keys[sampleSize]; + void *v = NULL; + int errors = 0; + + l = skiplist_new(SKIPLIST_FLAG_ALLOW_DUPLICATES, NULL, NULL); + + printf("%s: skiplist_new returned %p\n", __func__, l); + + for (i = 0; i < 4; i++) { + + for (k = 0; k < sampleSize; k++) { + if (!(k % 10000)) + printf("%s: (%d:%d)\n", __func__, i, k); + /* keys[k] = (void *)random(); */ + keys[k] = scramble(k); + if (skiplist_insert(l, keys[k], keys[k])) { + ++errors; + printf("error in insert #%d,#%d\n", i, k); + } + } + + printf("%s: inserts done\n", __func__); + sl_debug(l); + + for (k = 0; k < sampleSize; k++) { + + if (!(k % 10000)) + printf("[%d:%d]\n", i, k); + /* keys[k] = (void *)random(); */ + if (skiplist_search(l, keys[k], &v)) { + ++errors; + printf("error in search #%d,#%d\n", i, k); + } + + if (v != keys[k]) { + ++errors; + printf("search returned wrong value\n"); + } + } + printf("%s: searches done\n", __func__); + + + for (k = 0; k < sampleSize; k++) { + + if (!(k % 10000)) + printf("<%d:%d>\n", i, k); + /* keys[k] = (void *)random(); */ + if (skiplist_delete(l, keys[k], keys[k])) { + ++errors; + printf("error in delete\n"); + } + keys[k] = scramble(k ^ 0xf0f0f0f0); + if (skiplist_insert(l, keys[k], keys[k])) { + ++errors; + printf("error in insert #%d,#%d\n", i, k); + } + } + + printf("%s: del+inserts done\n", __func__); + sl_debug(l); + + for (k = 0; k < sampleSize; k++) { + + if (!(k % 10000)) + printf("{%d:%d}\n", i, k); + /* keys[k] = (void *)random(); */ + if (skiplist_delete_first(l)) { + ++errors; + printf("error in delete_first\n"); + } + } + } + + sl_debug(l); + + skiplist_free(l); + + return errors; +} + +int main(int argc, char **argv) +{ + int errors = sl_test(); + + if (errors) + return 1; + return 0; +} diff --git a/tests/subdir.am b/tests/subdir.am index 1edfda9bc2..f21e12ecbb 100644 --- a/tests/subdir.am +++ b/tests/subdir.am @@ -98,6 +98,7 @@ check_PROGRAMS = \ tests/lib/test_segv \ tests/lib/test_seqlock \ tests/lib/test_sig \ + tests/lib/test_skiplist \ tests/lib/test_stream \ tests/lib/test_table \ tests/lib/test_timer_correctness \ @@ -366,6 +367,10 @@ tests_lib_test_sig_CFLAGS = $(TESTS_CFLAGS) tests_lib_test_sig_CPPFLAGS = $(TESTS_CPPFLAGS) tests_lib_test_sig_LDADD = $(ALL_TESTS_LDADD) tests_lib_test_sig_SOURCES = tests/lib/test_sig.c +tests_lib_test_skiplist_CFLAGS = $(TESTS_CFLAGS) +tests_lib_test_skiplist_CPPFLAGS = $(TESTS_CPPFLAGS) +tests_lib_test_skiplist_LDADD = $(ALL_TESTS_LDADD) +tests_lib_test_skiplist_SOURCES = tests/lib/test_skiplist.c tests_lib_test_srcdest_table_CFLAGS = $(TESTS_CFLAGS) tests_lib_test_srcdest_table_CPPFLAGS = $(TESTS_CPPFLAGS) tests_lib_test_srcdest_table_LDADD = $(ALL_TESTS_LDADD)