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authorRiccardo Spagni <ric@spagni.net>2014-10-05 23:44:31 +0200
committerRiccardo Spagni <ric@spagni.net>2014-10-05 23:44:31 +0200
commit9ef094b356b4da7542c3cab898dac7e135b76903 (patch)
tree99b5876712b0b1551fc042fe75447b998e4b0fc1 /external/unbound/util/storage/lruhash.c
parentsplit mnemonic printout over 3 lines (diff)
downloadmonero-9ef094b356b4da7542c3cab898dac7e135b76903.tar.xz
added unbound to external deps
Diffstat (limited to 'external/unbound/util/storage/lruhash.c')
-rw-r--r--external/unbound/util/storage/lruhash.c544
1 files changed, 544 insertions, 0 deletions
diff --git a/external/unbound/util/storage/lruhash.c b/external/unbound/util/storage/lruhash.c
new file mode 100644
index 000000000..2c987a2e5
--- /dev/null
+++ b/external/unbound/util/storage/lruhash.c
@@ -0,0 +1,544 @@
+/*
+ * util/storage/lruhash.c - hashtable, hash function, LRU keeping.
+ *
+ * Copyright (c) 2007, NLnet Labs. All rights reserved.
+ *
+ * This software is open source.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * Neither the name of the NLNET LABS nor the names of its contributors may
+ * be used to endorse or promote products derived from this software without
+ * specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
+ * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/**
+ * \file
+ *
+ * This file contains a hashtable with LRU keeping of entries.
+ *
+ */
+
+#include "config.h"
+#include "util/storage/lruhash.h"
+#include "util/fptr_wlist.h"
+
+void
+bin_init(struct lruhash_bin* array, size_t size)
+{
+ size_t i;
+#ifdef THREADS_DISABLED
+ (void)array;
+#endif
+ for(i=0; i<size; i++) {
+ lock_quick_init(&array[i].lock);
+ lock_protect(&array[i].lock, &array[i],
+ sizeof(struct lruhash_bin));
+ }
+}
+
+struct lruhash*
+lruhash_create(size_t start_size, size_t maxmem, lruhash_sizefunc_t sizefunc,
+ lruhash_compfunc_t compfunc, lruhash_delkeyfunc_t delkeyfunc,
+ lruhash_deldatafunc_t deldatafunc, void* arg)
+{
+ struct lruhash* table = (struct lruhash*)calloc(1,
+ sizeof(struct lruhash));
+ if(!table)
+ return NULL;
+ lock_quick_init(&table->lock);
+ table->sizefunc = sizefunc;
+ table->compfunc = compfunc;
+ table->delkeyfunc = delkeyfunc;
+ table->deldatafunc = deldatafunc;
+ table->cb_arg = arg;
+ table->size = start_size;
+ table->size_mask = (int)(start_size-1);
+ table->lru_start = NULL;
+ table->lru_end = NULL;
+ table->num = 0;
+ table->space_used = 0;
+ table->space_max = maxmem;
+ table->array = calloc(table->size, sizeof(struct lruhash_bin));
+ if(!table->array) {
+ lock_quick_destroy(&table->lock);
+ free(table);
+ return NULL;
+ }
+ bin_init(table->array, table->size);
+ lock_protect(&table->lock, table, sizeof(*table));
+ lock_protect(&table->lock, table->array,
+ table->size*sizeof(struct lruhash_bin));
+ return table;
+}
+
+void
+bin_delete(struct lruhash* table, struct lruhash_bin* bin)
+{
+ struct lruhash_entry* p, *np;
+ void *d;
+ if(!bin)
+ return;
+ lock_quick_destroy(&bin->lock);
+ p = bin->overflow_list;
+ bin->overflow_list = NULL;
+ while(p) {
+ np = p->overflow_next;
+ d = p->data;
+ (*table->delkeyfunc)(p->key, table->cb_arg);
+ (*table->deldatafunc)(d, table->cb_arg);
+ p = np;
+ }
+}
+
+void
+bin_split(struct lruhash* table, struct lruhash_bin* newa,
+ int newmask)
+{
+ size_t i;
+ struct lruhash_entry *p, *np;
+ struct lruhash_bin* newbin;
+ /* move entries to new table. Notice that since hash x is mapped to
+ * bin x & mask, and new mask uses one more bit, so all entries in
+ * one bin will go into the old bin or bin | newbit */
+#ifndef THREADS_DISABLED
+ int newbit = newmask - table->size_mask;
+#endif
+ /* so, really, this task could also be threaded, per bin. */
+ /* LRU list is not changed */
+ for(i=0; i<table->size; i++)
+ {
+ lock_quick_lock(&table->array[i].lock);
+ p = table->array[i].overflow_list;
+ /* lock both destination bins */
+ lock_quick_lock(&newa[i].lock);
+ lock_quick_lock(&newa[newbit|i].lock);
+ while(p) {
+ np = p->overflow_next;
+ /* link into correct new bin */
+ newbin = &newa[p->hash & newmask];
+ p->overflow_next = newbin->overflow_list;
+ newbin->overflow_list = p;
+ p=np;
+ }
+ lock_quick_unlock(&newa[i].lock);
+ lock_quick_unlock(&newa[newbit|i].lock);
+ lock_quick_unlock(&table->array[i].lock);
+ }
+}
+
+void
+lruhash_delete(struct lruhash* table)
+{
+ size_t i;
+ if(!table)
+ return;
+ /* delete lock on hashtable to force check its OK */
+ lock_quick_destroy(&table->lock);
+ for(i=0; i<table->size; i++)
+ bin_delete(table, &table->array[i]);
+ free(table->array);
+ free(table);
+}
+
+void
+bin_overflow_remove(struct lruhash_bin* bin, struct lruhash_entry* entry)
+{
+ struct lruhash_entry* p = bin->overflow_list;
+ struct lruhash_entry** prevp = &bin->overflow_list;
+ while(p) {
+ if(p == entry) {
+ *prevp = p->overflow_next;
+ return;
+ }
+ prevp = &p->overflow_next;
+ p = p->overflow_next;
+ }
+}
+
+void
+reclaim_space(struct lruhash* table, struct lruhash_entry** list)
+{
+ struct lruhash_entry* d;
+ struct lruhash_bin* bin;
+ log_assert(table);
+ /* does not delete MRU entry, so table will not be empty. */
+ while(table->num > 1 && table->space_used > table->space_max) {
+ /* notice that since we hold the hashtable lock, nobody
+ can change the lru chain. So it cannot be deleted underneath
+ us. We still need the hashbin and entry write lock to make
+ sure we flush all users away from the entry.
+ which is unlikely, since it is LRU, if someone got a rdlock
+ it would be moved to front, but to be sure. */
+ d = table->lru_end;
+ /* specialised, delete from end of double linked list,
+ and we know num>1, so there is a previous lru entry. */
+ log_assert(d && d->lru_prev);
+ table->lru_end = d->lru_prev;
+ d->lru_prev->lru_next = NULL;
+ /* schedule entry for deletion */
+ bin = &table->array[d->hash & table->size_mask];
+ table->num --;
+ lock_quick_lock(&bin->lock);
+ bin_overflow_remove(bin, d);
+ d->overflow_next = *list;
+ *list = d;
+ lock_rw_wrlock(&d->lock);
+ table->space_used -= table->sizefunc(d->key, d->data);
+ if(table->markdelfunc)
+ (*table->markdelfunc)(d->key);
+ lock_rw_unlock(&d->lock);
+ lock_quick_unlock(&bin->lock);
+ }
+}
+
+struct lruhash_entry*
+bin_find_entry(struct lruhash* table,
+ struct lruhash_bin* bin, hashvalue_t hash, void* key)
+{
+ struct lruhash_entry* p = bin->overflow_list;
+ while(p) {
+ if(p->hash == hash && table->compfunc(p->key, key) == 0)
+ return p;
+ p = p->overflow_next;
+ }
+ return NULL;
+}
+
+void
+table_grow(struct lruhash* table)
+{
+ struct lruhash_bin* newa;
+ int newmask;
+ size_t i;
+ if(table->size_mask == (int)(((size_t)-1)>>1)) {
+ log_err("hash array malloc: size_t too small");
+ return;
+ }
+ /* try to allocate new array, if not fail */
+ newa = calloc(table->size*2, sizeof(struct lruhash_bin));
+ if(!newa) {
+ log_err("hash grow: malloc failed");
+ /* continue with smaller array. Though its slower. */
+ return;
+ }
+ bin_init(newa, table->size*2);
+ newmask = (table->size_mask << 1) | 1;
+ bin_split(table, newa, newmask);
+ /* delete the old bins */
+ lock_unprotect(&table->lock, table->array);
+ for(i=0; i<table->size; i++) {
+ lock_quick_destroy(&table->array[i].lock);
+ }
+ free(table->array);
+
+ table->size *= 2;
+ table->size_mask = newmask;
+ table->array = newa;
+ lock_protect(&table->lock, table->array,
+ table->size*sizeof(struct lruhash_bin));
+ return;
+}
+
+void
+lru_front(struct lruhash* table, struct lruhash_entry* entry)
+{
+ entry->lru_prev = NULL;
+ entry->lru_next = table->lru_start;
+ if(!table->lru_start)
+ table->lru_end = entry;
+ else table->lru_start->lru_prev = entry;
+ table->lru_start = entry;
+}
+
+void
+lru_remove(struct lruhash* table, struct lruhash_entry* entry)
+{
+ if(entry->lru_prev)
+ entry->lru_prev->lru_next = entry->lru_next;
+ else table->lru_start = entry->lru_next;
+ if(entry->lru_next)
+ entry->lru_next->lru_prev = entry->lru_prev;
+ else table->lru_end = entry->lru_prev;
+}
+
+void
+lru_touch(struct lruhash* table, struct lruhash_entry* entry)
+{
+ log_assert(table && entry);
+ if(entry == table->lru_start)
+ return; /* nothing to do */
+ /* remove from current lru position */
+ lru_remove(table, entry);
+ /* add at front */
+ lru_front(table, entry);
+}
+
+void
+lruhash_insert(struct lruhash* table, hashvalue_t hash,
+ struct lruhash_entry* entry, void* data, void* cb_arg)
+{
+ struct lruhash_bin* bin;
+ struct lruhash_entry* found, *reclaimlist=NULL;
+ size_t need_size;
+ fptr_ok(fptr_whitelist_hash_sizefunc(table->sizefunc));
+ fptr_ok(fptr_whitelist_hash_delkeyfunc(table->delkeyfunc));
+ fptr_ok(fptr_whitelist_hash_deldatafunc(table->deldatafunc));
+ fptr_ok(fptr_whitelist_hash_compfunc(table->compfunc));
+ fptr_ok(fptr_whitelist_hash_markdelfunc(table->markdelfunc));
+ need_size = table->sizefunc(entry->key, data);
+ if(cb_arg == NULL) cb_arg = table->cb_arg;
+
+ /* find bin */
+ lock_quick_lock(&table->lock);
+ bin = &table->array[hash & table->size_mask];
+ lock_quick_lock(&bin->lock);
+
+ /* see if entry exists already */
+ if(!(found=bin_find_entry(table, bin, hash, entry->key))) {
+ /* if not: add to bin */
+ entry->overflow_next = bin->overflow_list;
+ bin->overflow_list = entry;
+ lru_front(table, entry);
+ table->num++;
+ table->space_used += need_size;
+ } else {
+ /* if so: update data - needs a writelock */
+ table->space_used += need_size -
+ (*table->sizefunc)(found->key, found->data);
+ (*table->delkeyfunc)(entry->key, cb_arg);
+ lru_touch(table, found);
+ lock_rw_wrlock(&found->lock);
+ (*table->deldatafunc)(found->data, cb_arg);
+ found->data = data;
+ lock_rw_unlock(&found->lock);
+ }
+ lock_quick_unlock(&bin->lock);
+ if(table->space_used > table->space_max)
+ reclaim_space(table, &reclaimlist);
+ if(table->num >= table->size)
+ table_grow(table);
+ lock_quick_unlock(&table->lock);
+
+ /* finish reclaim if any (outside of critical region) */
+ while(reclaimlist) {
+ struct lruhash_entry* n = reclaimlist->overflow_next;
+ void* d = reclaimlist->data;
+ (*table->delkeyfunc)(reclaimlist->key, cb_arg);
+ (*table->deldatafunc)(d, cb_arg);
+ reclaimlist = n;
+ }
+}
+
+struct lruhash_entry*
+lruhash_lookup(struct lruhash* table, hashvalue_t hash, void* key, int wr)
+{
+ struct lruhash_entry* entry;
+ struct lruhash_bin* bin;
+ fptr_ok(fptr_whitelist_hash_compfunc(table->compfunc));
+
+ lock_quick_lock(&table->lock);
+ bin = &table->array[hash & table->size_mask];
+ lock_quick_lock(&bin->lock);
+ if((entry=bin_find_entry(table, bin, hash, key)))
+ lru_touch(table, entry);
+ lock_quick_unlock(&table->lock);
+
+ if(entry) {
+ if(wr) { lock_rw_wrlock(&entry->lock); }
+ else { lock_rw_rdlock(&entry->lock); }
+ }
+ lock_quick_unlock(&bin->lock);
+ return entry;
+}
+
+void
+lruhash_remove(struct lruhash* table, hashvalue_t hash, void* key)
+{
+ struct lruhash_entry* entry;
+ struct lruhash_bin* bin;
+ void *d;
+ fptr_ok(fptr_whitelist_hash_sizefunc(table->sizefunc));
+ fptr_ok(fptr_whitelist_hash_delkeyfunc(table->delkeyfunc));
+ fptr_ok(fptr_whitelist_hash_deldatafunc(table->deldatafunc));
+ fptr_ok(fptr_whitelist_hash_compfunc(table->compfunc));
+ fptr_ok(fptr_whitelist_hash_markdelfunc(table->markdelfunc));
+
+ lock_quick_lock(&table->lock);
+ bin = &table->array[hash & table->size_mask];
+ lock_quick_lock(&bin->lock);
+ if((entry=bin_find_entry(table, bin, hash, key))) {
+ bin_overflow_remove(bin, entry);
+ lru_remove(table, entry);
+ } else {
+ lock_quick_unlock(&table->lock);
+ lock_quick_unlock(&bin->lock);
+ return;
+ }
+ table->num--;
+ table->space_used -= (*table->sizefunc)(entry->key, entry->data);
+ lock_quick_unlock(&table->lock);
+ lock_rw_wrlock(&entry->lock);
+ if(table->markdelfunc)
+ (*table->markdelfunc)(entry->key);
+ lock_rw_unlock(&entry->lock);
+ lock_quick_unlock(&bin->lock);
+ /* finish removal */
+ d = entry->data;
+ (*table->delkeyfunc)(entry->key, table->cb_arg);
+ (*table->deldatafunc)(d, table->cb_arg);
+}
+
+/** clear bin, respecting locks, does not do space, LRU */
+static void
+bin_clear(struct lruhash* table, struct lruhash_bin* bin)
+{
+ struct lruhash_entry* p, *np;
+ void *d;
+ lock_quick_lock(&bin->lock);
+ p = bin->overflow_list;
+ while(p) {
+ lock_rw_wrlock(&p->lock);
+ np = p->overflow_next;
+ d = p->data;
+ if(table->markdelfunc)
+ (*table->markdelfunc)(p->key);
+ lock_rw_unlock(&p->lock);
+ (*table->delkeyfunc)(p->key, table->cb_arg);
+ (*table->deldatafunc)(d, table->cb_arg);
+ p = np;
+ }
+ bin->overflow_list = NULL;
+ lock_quick_unlock(&bin->lock);
+}
+
+void
+lruhash_clear(struct lruhash* table)
+{
+ size_t i;
+ if(!table)
+ return;
+ fptr_ok(fptr_whitelist_hash_delkeyfunc(table->delkeyfunc));
+ fptr_ok(fptr_whitelist_hash_deldatafunc(table->deldatafunc));
+ fptr_ok(fptr_whitelist_hash_markdelfunc(table->markdelfunc));
+
+ lock_quick_lock(&table->lock);
+ for(i=0; i<table->size; i++) {
+ bin_clear(table, &table->array[i]);
+ }
+ table->lru_start = NULL;
+ table->lru_end = NULL;
+ table->num = 0;
+ table->space_used = 0;
+ lock_quick_unlock(&table->lock);
+}
+
+void
+lruhash_status(struct lruhash* table, const char* id, int extended)
+{
+ lock_quick_lock(&table->lock);
+ log_info("%s: %u entries, memory %u / %u",
+ id, (unsigned)table->num, (unsigned)table->space_used,
+ (unsigned)table->space_max);
+ log_info(" itemsize %u, array %u, mask %d",
+ (unsigned)(table->num? table->space_used/table->num : 0),
+ (unsigned)table->size, table->size_mask);
+ if(extended) {
+ size_t i;
+ int min=(int)table->size*2, max=-2;
+ for(i=0; i<table->size; i++) {
+ int here = 0;
+ struct lruhash_entry *en;
+ lock_quick_lock(&table->array[i].lock);
+ en = table->array[i].overflow_list;
+ while(en) {
+ here ++;
+ en = en->overflow_next;
+ }
+ lock_quick_unlock(&table->array[i].lock);
+ if(extended >= 2)
+ log_info("bin[%d] %d", (int)i, here);
+ if(here > max) max = here;
+ if(here < min) min = here;
+ }
+ log_info(" bin min %d, avg %.2lf, max %d", min,
+ (double)table->num/(double)table->size, max);
+ }
+ lock_quick_unlock(&table->lock);
+}
+
+size_t
+lruhash_get_mem(struct lruhash* table)
+{
+ size_t s;
+ lock_quick_lock(&table->lock);
+ s = sizeof(struct lruhash) + table->space_used;
+#ifdef USE_THREAD_DEBUG
+ if(table->size != 0) {
+ size_t i;
+ for(i=0; i<table->size; i++)
+ s += sizeof(struct lruhash_bin) +
+ lock_get_mem(&table->array[i].lock);
+ }
+#else /* no THREAD_DEBUG */
+ if(table->size != 0)
+ s += (table->size)*(sizeof(struct lruhash_bin) +
+ lock_get_mem(&table->array[0].lock));
+#endif
+ lock_quick_unlock(&table->lock);
+ s += lock_get_mem(&table->lock);
+ return s;
+}
+
+void
+lruhash_setmarkdel(struct lruhash* table, lruhash_markdelfunc_t md)
+{
+ lock_quick_lock(&table->lock);
+ table->markdelfunc = md;
+ lock_quick_unlock(&table->lock);
+}
+
+void
+lruhash_traverse(struct lruhash* h, int wr,
+ void (*func)(struct lruhash_entry*, void*), void* arg)
+{
+ size_t i;
+ struct lruhash_entry* e;
+
+ lock_quick_lock(&h->lock);
+ for(i=0; i<h->size; i++) {
+ lock_quick_lock(&h->array[i].lock);
+ for(e = h->array[i].overflow_list; e; e = e->overflow_next) {
+ if(wr) {
+ lock_rw_wrlock(&e->lock);
+ } else {
+ lock_rw_rdlock(&e->lock);
+ }
+ (*func)(e, arg);
+ lock_rw_unlock(&e->lock);
+ }
+ lock_quick_unlock(&h->array[i].lock);
+ }
+ lock_quick_unlock(&h->lock);
+}