* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
-
#include "glheader.h"
#include "imports.h"
#include "glapi/glthread.h"
#include "hash.h"
-
-
-#define TABLE_SIZE 1023 /**< Size of lookup table/array */
-
-#define HASH_FUNC(K) ((K) % TABLE_SIZE)
-
+#include "hash_table.h"
/**
- * An entry in the hash table.
+ * Magic GLuint object name that gets stored outside of the struct hash_table.
+ *
+ * The hash table needs a particular pointer to be the marker for a key that
+ * was deleted from the table, along with NULL for the "never allocated in the
+ * table" marker. Legacy GL allows any GLuint to be used as a GL object name,
+ * and we use a 1:1 mapping from GLuints to key pointers, so we need to be
+ * able to track a GLuint that happens to match the deleted key outside of
+ * struct hash_table. We tell the hash table to use "1" as the deleted key
+ * value, so that we test the deleted-key-in-the-table path as best we can.
*/
-struct HashEntry {
- GLuint Key; /**< the entry's key */
- void *Data; /**< the entry's data */
- struct HashEntry *Next; /**< pointer to next entry */
-};
-
+#define DELETED_KEY_VALUE 1
/**
* The hash table data structure.
*/
struct _mesa_HashTable {
- struct HashEntry *Table[TABLE_SIZE]; /**< the lookup table */
+ struct hash_table *ht;
GLuint MaxKey; /**< highest key inserted so far */
_glthread_Mutex Mutex; /**< mutual exclusion lock */
_glthread_Mutex WalkMutex; /**< for _mesa_HashWalk() */
GLboolean InDeleteAll; /**< Debug check */
+ /** Value that would be in the table for DELETED_KEY_VALUE. */
+ void *deleted_key_data;
};
+/** @{
+ * Mapping from our use of GLuint as both the key and the hash value to the
+ * hash_table.h API
+ *
+ * There exist many integer hash functions, designed to avoid collisions when
+ * the integers are spread across key space with some patterns. In GL, the
+ * pattern (in the case of glGen*()ed object IDs) is that the keys are unique
+ * contiguous integers starting from 1. Because of that, we just use the key
+ * as the hash value, to minimize the cost of the hash function. If objects
+ * are never deleted, we will never see a collision in the table, because the
+ * table resizes itself when it approaches full, and thus key % table_size ==
+ * key.
+ *
+ * The case where we could have collisions for genned objects would be
+ * something like: glGenBuffers(&a, 100); glDeleteBuffers(&a + 50, 50);
+ * glGenBuffers(&b, 100), because objects 1-50 and 101-200 are allocated at
+ * the end of that sequence, instead of 1-150. So far it doesn't appear to be
+ * a problem.
+ */
+static bool
+uint_key_compare(const void *a, const void *b)
+{
+ return a == b;
+}
+
+static uint32_t
+uint_hash(GLuint id)
+{
+ return id;
+}
+static void *
+uint_key(GLuint id)
+{
+ return (void *)(uintptr_t) id;
+}
+/** @} */
/**
* Create a new hash table.
_mesa_NewHashTable(void)
{
struct _mesa_HashTable *table = CALLOC_STRUCT(_mesa_HashTable);
+
+ table->ht = _mesa_hash_table_create(NULL, uint_key_compare);
+ _mesa_hash_table_set_deleted_key(table->ht, uint_key(DELETED_KEY_VALUE));
if (table) {
_glthread_INIT_MUTEX(table->Mutex);
_glthread_INIT_MUTEX(table->WalkMutex);
void
_mesa_DeleteHashTable(struct _mesa_HashTable *table)
{
- GLuint pos;
assert(table);
- for (pos = 0; pos < TABLE_SIZE; pos++) {
- struct HashEntry *entry = table->Table[pos];
- while (entry) {
- struct HashEntry *next = entry->Next;
- if (entry->Data) {
- _mesa_problem(NULL,
- "In _mesa_DeleteHashTable, found non-freed data");
- }
- free(entry);
- entry = next;
- }
+
+ if (_mesa_hash_table_next_entry(table->ht, NULL) != NULL) {
+ _mesa_problem(NULL, "In _mesa_DeleteHashTable, found non-freed data");
}
+
+ _mesa_hash_table_destroy(table->ht, NULL);
+
_glthread_DESTROY_MUTEX(table->Mutex);
_glthread_DESTROY_MUTEX(table->WalkMutex);
free(table);
static inline void *
_mesa_HashLookup_unlocked(struct _mesa_HashTable *table, GLuint key)
{
- GLuint pos;
- const struct HashEntry *entry;
+ const struct hash_entry *entry;
assert(table);
assert(key);
- pos = HASH_FUNC(key);
- entry = table->Table[pos];
- while (entry) {
- if (entry->Key == key) {
- return entry->Data;
- }
- entry = entry->Next;
- }
- return NULL;
+ if (key == DELETED_KEY_VALUE)
+ return table->deleted_key_data;
+
+ entry = _mesa_hash_table_search(table->ht, uint_hash(key), uint_key(key));
+ if (!entry)
+ return NULL;
+
+ return entry->data;
}
void
_mesa_HashInsert(struct _mesa_HashTable *table, GLuint key, void *data)
{
- /* search for existing entry with this key */
- GLuint pos;
- struct HashEntry *entry;
+ uint32_t hash = uint_hash(key);
+ struct hash_entry *entry;
assert(table);
assert(key);
if (key > table->MaxKey)
table->MaxKey = key;
- pos = HASH_FUNC(key);
-
- /* check if replacing an existing entry with same key */
- for (entry = table->Table[pos]; entry; entry = entry->Next) {
- if (entry->Key == key) {
- /* replace entry's data */
-#if 0 /* not sure this check is always valid */
- if (entry->Data) {
- _mesa_problem(NULL, "Memory leak detected in _mesa_HashInsert");
- }
-#endif
- entry->Data = data;
- _glthread_UNLOCK_MUTEX(table->Mutex);
- return;
+ if (key == DELETED_KEY_VALUE) {
+ table->deleted_key_data = data;
+ } else {
+ entry = _mesa_hash_table_search(table->ht, hash, uint_key(key));
+ if (entry) {
+ entry->data = data;
+ } else {
+ _mesa_hash_table_insert(table->ht, hash, uint_key(key), data);
}
}
- /* alloc and insert new table entry */
- entry = MALLOC_STRUCT(HashEntry);
- if (entry) {
- entry->Key = key;
- entry->Data = data;
- entry->Next = table->Table[pos];
- table->Table[pos] = entry;
- }
-
_glthread_UNLOCK_MUTEX(table->Mutex);
}
void
_mesa_HashRemove(struct _mesa_HashTable *table, GLuint key)
{
- GLuint pos;
- struct HashEntry *entry, *prev;
+ struct hash_entry *entry;
assert(table);
assert(key);
}
_glthread_LOCK_MUTEX(table->Mutex);
-
- pos = HASH_FUNC(key);
- prev = NULL;
- entry = table->Table[pos];
- while (entry) {
- if (entry->Key == key) {
- /* found it! */
- if (prev) {
- prev->Next = entry->Next;
- }
- else {
- table->Table[pos] = entry->Next;
- }
- free(entry);
- _glthread_UNLOCK_MUTEX(table->Mutex);
- return;
- }
- prev = entry;
- entry = entry->Next;
+ if (key == DELETED_KEY_VALUE) {
+ table->deleted_key_data = NULL;
+ } else {
+ entry = _mesa_hash_table_search(table->ht, uint_hash(key), uint_key(key));
+ _mesa_hash_table_remove(table->ht, entry);
}
-
_glthread_UNLOCK_MUTEX(table->Mutex);
}
void (*callback)(GLuint key, void *data, void *userData),
void *userData)
{
- GLuint pos;
+ struct hash_entry *entry;
+
ASSERT(table);
ASSERT(callback);
_glthread_LOCK_MUTEX(table->Mutex);
table->InDeleteAll = GL_TRUE;
- for (pos = 0; pos < TABLE_SIZE; pos++) {
- struct HashEntry *entry, *next;
- for (entry = table->Table[pos]; entry; entry = next) {
- callback(entry->Key, entry->Data, userData);
- next = entry->Next;
- free(entry);
- }
- table->Table[pos] = NULL;
+ hash_table_foreach(table->ht, entry) {
+ callback((uintptr_t)entry->key, entry->data, userData);
+ _mesa_hash_table_remove(table->ht, entry);
+ }
+ if (table->deleted_key_data) {
+ callback(DELETED_KEY_VALUE, table->deleted_key_data, userData);
+ table->deleted_key_data = NULL;
}
table->InDeleteAll = GL_FALSE;
_glthread_UNLOCK_MUTEX(table->Mutex);
{
/* cast-away const */
struct _mesa_HashTable *table2 = (struct _mesa_HashTable *) table;
- GLuint pos;
+ struct hash_entry *entry;
+
ASSERT(table);
ASSERT(callback);
_glthread_LOCK_MUTEX(table2->WalkMutex);
- for (pos = 0; pos < TABLE_SIZE; pos++) {
- struct HashEntry *entry, *next;
- for (entry = table->Table[pos]; entry; entry = next) {
- /* save 'next' pointer now in case the callback deletes the entry */
- next = entry->Next;
- callback(entry->Key, entry->Data, userData);
- }
+ hash_table_foreach(table->ht, entry) {
+ callback((uintptr_t)entry->key, entry->data, userData);
}
+ if (table->deleted_key_data)
+ callback(DELETED_KEY_VALUE, table->deleted_key_data, userData);
_glthread_UNLOCK_MUTEX(table2->WalkMutex);
}
-
-/**
- * Return the key of the "first" entry in the hash table.
- * While holding the lock, walks through all table positions until finding
- * the first entry of the first non-empty one.
- *
- * \param table the hash table
- * \return key for the "first" entry in the hash table.
- */
-GLuint
-_mesa_HashFirstEntry(struct _mesa_HashTable *table)
-{
- GLuint pos;
- assert(table);
- _glthread_LOCK_MUTEX(table->Mutex);
- for (pos = 0; pos < TABLE_SIZE; pos++) {
- if (table->Table[pos]) {
- _glthread_UNLOCK_MUTEX(table->Mutex);
- return table->Table[pos]->Key;
- }
- }
- _glthread_UNLOCK_MUTEX(table->Mutex);
- return 0;
-}
-
-
-/**
- * Given a hash table key, return the next key. This is used to walk
- * over all entries in the table. Note that the keys returned during
- * walking won't be in any particular order.
- * \return next hash key or 0 if end of table.
- */
-GLuint
-_mesa_HashNextEntry(const struct _mesa_HashTable *table, GLuint key)
+static void
+debug_print_entry(GLuint key, void *data, void *userData)
{
- const struct HashEntry *entry;
- GLuint pos;
-
- assert(table);
- assert(key);
-
- /* Find the entry with given key */
- pos = HASH_FUNC(key);
- for (entry = table->Table[pos]; entry ; entry = entry->Next) {
- if (entry->Key == key) {
- break;
- }
- }
-
- if (!entry) {
- /* the given key was not found, so we can't find the next entry */
- return 0;
- }
-
- if (entry->Next) {
- /* return next in linked list */
- return entry->Next->Key;
- }
- else {
- /* look for next non-empty table slot */
- pos++;
- while (pos < TABLE_SIZE) {
- if (table->Table[pos]) {
- return table->Table[pos]->Key;
- }
- pos++;
- }
- return 0;
- }
+ _mesa_debug(NULL, "%u %p\n", key, data);
}
-
/**
* Dump contents of hash table for debugging.
*
void
_mesa_HashPrint(const struct _mesa_HashTable *table)
{
- GLuint pos;
- assert(table);
- for (pos = 0; pos < TABLE_SIZE; pos++) {
- const struct HashEntry *entry = table->Table[pos];
- while (entry) {
- _mesa_debug(NULL, "%u %p\n", entry->Key, entry->Data);
- entry = entry->Next;
- }
- }
+ if (table->deleted_key_data)
+ debug_print_entry(DELETED_KEY_VALUE, table->deleted_key_data, NULL);
+ _mesa_HashWalk(table, debug_print_entry, NULL);
}
-
/**
* Find a block of adjacent unused hash keys.
*
GLuint
_mesa_HashFindFreeKeyBlock(struct _mesa_HashTable *table, GLuint numKeys)
{
- const GLuint maxKey = ~((GLuint) 0);
+ const GLuint maxKey = ~((GLuint) 0) - 1;
_glthread_LOCK_MUTEX(table->Mutex);
if (maxKey - numKeys > table->MaxKey) {
/* the quick solution */
GLuint
_mesa_HashNumEntries(const struct _mesa_HashTable *table)
{
- GLuint pos, count = 0;
+ struct hash_entry *entry;
+ GLuint count = 0;
- for (pos = 0; pos < TABLE_SIZE; pos++) {
- const struct HashEntry *entry;
- for (entry = table->Table[pos]; entry; entry = entry->Next) {
- count++;
- }
- }
+ if (table->deleted_key_data)
+ count++;
- return count;
-}
-
-
-
-#if 0 /* debug only */
+ hash_table_foreach(table->ht, entry)
+ count++;
-/**
- * Test walking over all the entries in a hash table.
- */
-static void
-test_hash_walking(void)
-{
- struct _mesa_HashTable *t = _mesa_NewHashTable();
- const GLuint limit = 50000;
- GLuint i;
-
- /* create some entries */
- for (i = 0; i < limit; i++) {
- GLuint dummy;
- GLuint k = (rand() % (limit * 10)) + 1;
- while (_mesa_HashLookup(t, k)) {
- /* id already in use, try another */
- k = (rand() % (limit * 10)) + 1;
- }
- _mesa_HashInsert(t, k, &dummy);
- }
-
- /* walk over all entries */
- {
- GLuint k = _mesa_HashFirstEntry(t);
- GLuint count = 0;
- while (k) {
- GLuint knext = _mesa_HashNextEntry(t, k);
- assert(knext != k);
- _mesa_HashRemove(t, k);
- count++;
- k = knext;
- }
- assert(count == limit);
- k = _mesa_HashFirstEntry(t);
- assert(k==0);
- }
-
- _mesa_DeleteHashTable(t);
-}
-
-
-void
-_mesa_test_hash_functions(void)
-{
- int a, b, c;
- struct _mesa_HashTable *t;
-
- t = _mesa_NewHashTable();
- _mesa_HashInsert(t, 501, &a);
- _mesa_HashInsert(t, 10, &c);
- _mesa_HashInsert(t, 0xfffffff8, &b);
- /*_mesa_HashPrint(t);*/
-
- assert(_mesa_HashLookup(t,501));
- assert(!_mesa_HashLookup(t,1313));
- assert(_mesa_HashFindFreeKeyBlock(t, 100));
-
- _mesa_DeleteHashTable(t);
-
- test_hash_walking();
+ return count;
}
-
-#endif
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