unbound/util/storage/slabhash.c

   1 /*
   2  * util/storage/slabhash.c - hashtable consisting of several smaller tables.
   3  *
   4  * Copyright (c) 2007, NLnet Labs. All rights reserved.
   5  *
   6  * This software is open source.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  *
  12  * Redistributions of source code must retain the above copyright notice,
  13  * this list of conditions and the following disclaimer.
  14  *
  15  * Redistributions in binary form must reproduce the above copyright notice,
  16  * this list of conditions and the following disclaimer in the documentation
  17  * and/or other materials provided with the distribution.
  18  *
  19  * Neither the name of the NLNET LABS nor the names of its contributors may
  20  * be used to endorse or promote products derived from this software without
  21  * specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  24  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  25  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  26  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  27  * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  28  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
  29  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  30  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  31  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  32  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  33  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  34  */
  35
  36 /**
  37  * \file
  38  *
  39  * Implementation of hash table that consists of smaller hash tables.
  40  * This results in a partitioned lruhash table.
  41  * It cannot grow, but that gives it the ability to have multiple
  42  * locks. Also this means there are multiple LRU lists.
  43  */
  44
  45 #include "config.h"
  46 #include "util/storage/slabhash.h"
  47
  48 struct slabhash* slabhash_create(size_t numtables, size_t start_size,
  49         size_t maxmem, lruhash_sizefunc_t sizefunc,
  50         lruhash_compfunc_t compfunc, lruhash_delkeyfunc_t delkeyfunc,
  51         lruhash_deldatafunc_t deldatafunc, void* arg)
  52 {
  53         size_t i;
  54         struct slabhash* sl = (struct slabhash*)calloc(1,
  55                 sizeof(struct slabhash));
  56         if(!sl) return NULL;
  57         sl->size = numtables;
  58         log_assert(sl->size > 0);
  59         sl->array = (struct lruhash**)calloc(sl->size, sizeof(struct lruhash*));
  60         if(!sl->array) {
  61                 free(sl);
  62                 return NULL;
  63         }
  64         sl->mask = (uint32_t)(sl->size - 1);
  65         if(sl->mask == 0) {
  66                 sl->shift = 0;
  67         } else {
  68                 log_assert( (sl->size & sl->mask) == 0
  69                         /* size must be power of 2 */ );
  70                 sl->shift = 0;
  71                 while(!(sl->mask & 0x80000000)) {
  72                         sl->mask <<= 1;
  73                         sl->shift ++;
  74                 }
  75         }
  76         for(i=0; i<sl->size; i++) {
  77                 sl->array[i] = lruhash_create(start_size, maxmem / sl->size,
  78                         sizefunc, compfunc, delkeyfunc, deldatafunc, arg);
  79                 if(!sl->array[i]) {
  80                         slabhash_delete(sl);
  81                         return NULL;
  82                 }
  83         }
  84         return sl;
  85 }
  86
  87 void slabhash_delete(struct slabhash* sl)
  88 {
  89         if(!sl)
  90                 return;
  91         if(sl->array) {
  92                 size_t i;
  93                 for(i=0; i<sl->size; i++)
  94                         lruhash_delete(sl->array[i]);
  95                 free(sl->array);
  96         }
  97         free(sl);
  98 }
  99
 100 void slabhash_clear(struct slabhash* sl)
 101 {
 102         size_t i;
 103         if(!sl)
 104                 return;
 105         for(i=0; i<sl->size; i++)
 106                 lruhash_clear(sl->array[i]);
 107 }
 108
 109 /** helper routine to calculate the slabhash index */
 110 static unsigned int
 111 slab_idx(struct slabhash* sl, hashvalue_t hash)
 112 {
 113         return ((hash & sl->mask) >> sl->shift);
 114 }
 115
 116 void slabhash_insert(struct slabhash* sl, hashvalue_t hash,
 117         struct lruhash_entry* entry, void* data, void* arg)
 118 {
 119         lruhash_insert(sl->array[slab_idx(sl, hash)], hash, entry, data, arg);
 120 }
 121
 122 struct lruhash_entry* slabhash_lookup(struct slabhash* sl,
 123         hashvalue_t hash, void* key, int wr)
 124 {
 125         return lruhash_lookup(sl->array[slab_idx(sl, hash)], hash, key, wr);
 126 }
 127
 128 void slabhash_remove(struct slabhash* sl, hashvalue_t hash, void* key)
 129 {
 130         lruhash_remove(sl->array[slab_idx(sl, hash)], hash, key);
 131 }
 132
 133 void slabhash_status(struct slabhash* sl, const char* id, int extended)
 134 {
 135         size_t i;
 136         char num[17];
 137         log_info("Slabhash %s: %u tables mask=%x shift=%d",
 138                 id, (unsigned)sl->size, (unsigned)sl->mask, sl->shift);
 139         for(i=0; i<sl->size; i++) {
 140                 snprintf(num, sizeof(num), "table %u", (unsigned)i);
 141                 lruhash_status(sl->array[i], num, extended);
 142         }
 143 }
 144
 145 size_t slabhash_get_size(struct slabhash* sl)
 146 {
 147         size_t i, total = 0;
 148         for(i=0; i<sl->size; i++) {
 149                 lock_quick_lock(&sl->array[i]->lock);
 150                 total += sl->array[i]->space_max;
 151                 lock_quick_unlock(&sl->array[i]->lock);
 152         }
 153         return total;
 154 }
 155
 156 size_t slabhash_get_mem(struct slabhash* sl)
 157 {
 158         size_t i, total = sizeof(*sl);
 159         total += sizeof(struct lruhash*)*sl->size;
 160         for(i=0; i<sl->size; i++) {
 161                 total += lruhash_get_mem(sl->array[i]);
 162         }
 163         return total;
 164 }
 165
 166 struct lruhash* slabhash_gettable(struct slabhash* sl, hashvalue_t hash)
 167 {
 168         return sl->array[slab_idx(sl, hash)];
 169 }
 170
 171 /* test code, here to avoid linking problems with fptr_wlist */
 172 /** delete key */
 173 static void delkey(struct slabhash_testkey* k) {
 174         lock_rw_destroy(&k->entry.lock); free(k);}
 175 /** delete data */
 176 static void deldata(struct slabhash_testdata* d) {free(d);}
 177
 178 size_t test_slabhash_sizefunc(void* ATTR_UNUSED(key), void* ATTR_UNUSED(data))
 179 {
 180         return sizeof(struct slabhash_testkey) +
 181                 sizeof(struct slabhash_testdata);
 182 }
 183
 184 int test_slabhash_compfunc(void* key1, void* key2)
 185 {
 186         struct slabhash_testkey* k1 = (struct slabhash_testkey*)key1;
 187         struct slabhash_testkey* k2 = (struct slabhash_testkey*)key2;
 188         if(k1->id == k2->id)
 189                 return 0;
 190         if(k1->id > k2->id)
 191                 return 1;
 192         return -1;
 193 }
 194
 195 void test_slabhash_delkey(void* key, void* ATTR_UNUSED(arg))
 196 {
 197         delkey((struct slabhash_testkey*)key);
 198 }
 199
 200 void test_slabhash_deldata(void* data, void* ATTR_UNUSED(arg))
 201 {
 202         deldata((struct slabhash_testdata*)data);
 203 }
 204
 205 void slabhash_setmarkdel(struct slabhash* sl, lruhash_markdelfunc_t md)
 206 {
 207         size_t i;
 208         for(i=0; i<sl->size; i++) {
 209                 lruhash_setmarkdel(sl->array[i], md);
 210         }
 211 }
 212
 213 void slabhash_traverse(struct slabhash* sh, int wr,
 214         void (*func)(struct lruhash_entry*, void*), void* arg)
 215 {
 216         size_t i;
 217         for(i=0; i<sh->size; i++)
 218                 lruhash_traverse(sh->array[i], wr, func, arg);
 219 }
 220
 221 size_t count_slabhash_entries(struct slabhash* sh)
 222 {
 223         size_t slab, cnt = 0;
 224
 225         for(slab=0; slab<sh->size; slab++) {
 226                 lock_quick_lock(&sh->array[slab]->lock);
 227                 cnt += sh->array[slab]->num;
 228                 lock_quick_unlock(&sh->array[slab]->lock);
 229         }
 230         return cnt;
 231 }