* OTHER DEALINGS IN THE SOFTWARE.
*/
+#include "errors.h"
#include "glheader.h"
-#include "imports.h"
#include "hash.h"
#include "util/hash_table.h"
+#include "util/u_memory.h"
-/**
- * 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.
- */
-#define DELETED_KEY_VALUE 1
-
-/**
- * The hash table data structure.
- */
-struct _mesa_HashTable {
- struct hash_table *ht;
- GLuint MaxKey; /**< highest key inserted so far */
- mtx_t Mutex; /**< mutual exclusion lock */
- mtx_t 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 uint32_t
-uint_key_hash(const void *key)
-{
- return uint_hash((uintptr_t)key);
-}
-
-static void *
-uint_key(GLuint id)
-{
- return (void *)(uintptr_t) id;
-}
-/** @} */
/**
* Create a new hash table.
}
_mesa_hash_table_set_deleted_key(table->ht, uint_key(DELETED_KEY_VALUE));
- mtx_init(&table->Mutex, mtx_plain);
- mtx_init(&table->WalkMutex, mtx_plain);
+ /*
+ * Needs to be recursive, since the callback in _mesa_HashWalk()
+ * is allowed to call _mesa_HashRemove().
+ */
+ mtx_init(&table->Mutex, mtx_recursive);
}
else {
_mesa_error_no_memory(__func__);
_mesa_hash_table_destroy(table->ht, NULL);
mtx_destroy(&table->Mutex);
- mtx_destroy(&table->WalkMutex);
free(table);
}
if (key == DELETED_KEY_VALUE)
return table->deleted_key_data;
- entry = _mesa_hash_table_search(table->ht, uint_key(key));
+ entry = _mesa_hash_table_search_pre_hashed(table->ht,
+ uint_hash(key),
+ uint_key(key));
if (!entry)
return NULL;
_mesa_HashLookup(struct _mesa_HashTable *table, GLuint key)
{
void *res;
- assert(table);
- mtx_lock(&table->Mutex);
+ _mesa_HashLockMutex(table);
res = _mesa_HashLookup_unlocked(table, key);
- mtx_unlock(&table->Mutex);
+ _mesa_HashUnlockMutex(table);
return res;
}
}
-/**
- * Lock the hash table mutex.
- *
- * This function should be used when multiple objects need
- * to be looked up in the hash table, to avoid having to lock
- * and unlock the mutex each time.
- *
- * \param table the hash table.
- */
-void
-_mesa_HashLockMutex(struct _mesa_HashTable *table)
-{
- assert(table);
- mtx_lock(&table->Mutex);
-}
-
-
-/**
- * Unlock the hash table mutex.
- *
- * \param table the hash table.
- */
-void
-_mesa_HashUnlockMutex(struct _mesa_HashTable *table)
-{
- assert(table);
- mtx_unlock(&table->Mutex);
-}
-
-
static inline void
_mesa_HashInsert_unlocked(struct _mesa_HashTable *table, GLuint key, void *data)
{
void
_mesa_HashInsert(struct _mesa_HashTable *table, GLuint key, void *data)
{
- assert(table);
- mtx_lock(&table->Mutex);
+ _mesa_HashLockMutex(table);
_mesa_HashInsert_unlocked(table, key, data);
- mtx_unlock(&table->Mutex);
+ _mesa_HashUnlockMutex(table);
}
* While holding the hash table's lock, searches the entry with the matching
* key and unlinks it.
*/
-void
-_mesa_HashRemove(struct _mesa_HashTable *table, GLuint key)
+static inline void
+_mesa_HashRemove_unlocked(struct _mesa_HashTable *table, GLuint key)
{
struct hash_entry *entry;
assert(table);
assert(key);
- /* have to check this outside of mutex lock */
- if (table->InDeleteAll) {
- _mesa_problem(NULL, "_mesa_HashRemove illegally called from "
- "_mesa_HashDeleteAll callback function");
- return;
- }
+ /* assert if _mesa_HashRemove illegally called from _mesa_HashDeleteAll
+ * callback function. Have to check this outside of mutex lock.
+ */
+ assert(!table->InDeleteAll);
- mtx_lock(&table->Mutex);
if (key == DELETED_KEY_VALUE) {
table->deleted_key_data = NULL;
} else {
- entry = _mesa_hash_table_search(table->ht, uint_key(key));
+ entry = _mesa_hash_table_search_pre_hashed(table->ht,
+ uint_hash(key),
+ uint_key(key));
_mesa_hash_table_remove(table->ht, entry);
}
- mtx_unlock(&table->Mutex);
}
+void
+_mesa_HashRemoveLocked(struct _mesa_HashTable *table, GLuint key)
+{
+ _mesa_HashRemove_unlocked(table, key);
+}
+
+void
+_mesa_HashRemove(struct _mesa_HashTable *table, GLuint key)
+{
+ _mesa_HashLockMutex(table);
+ _mesa_HashRemove_unlocked(table, key);
+ _mesa_HashUnlockMutex(table);
+}
/**
* Delete all entries in a hash table, but don't delete the table itself.
void (*callback)(GLuint key, void *data, void *userData),
void *userData)
{
- struct hash_entry *entry;
-
- assert(table);
assert(callback);
- mtx_lock(&table->Mutex);
+ _mesa_HashLockMutex(table);
table->InDeleteAll = GL_TRUE;
hash_table_foreach(table->ht, entry) {
callback((uintptr_t)entry->key, entry->data, userData);
table->deleted_key_data = NULL;
}
table->InDeleteAll = GL_FALSE;
- mtx_unlock(&table->Mutex);
+ _mesa_HashUnlockMutex(table);
}
/**
* Walk over all entries in a hash table, calling callback function for each.
- * Note: we use a separate mutex in this function to avoid a recursive
- * locking deadlock (in case the callback calls _mesa_HashRemove()) and to
- * prevent multiple threads/contexts from getting tangled up.
- * A lock-less version of this function could be used when the table will
- * not be modified.
* \param table the hash table to walk
* \param callback the callback function
* \param userData arbitrary pointer to pass along to the callback
* (this is typically a struct gl_context pointer)
*/
-void
-_mesa_HashWalk(const struct _mesa_HashTable *table,
- void (*callback)(GLuint key, void *data, void *userData),
- void *userData)
+static void
+hash_walk_unlocked(const struct _mesa_HashTable *table,
+ void (*callback)(GLuint key, void *data, void *userData),
+ void *userData)
{
- /* cast-away const */
- struct _mesa_HashTable *table2 = (struct _mesa_HashTable *) table;
- struct hash_entry *entry;
-
assert(table);
assert(callback);
- mtx_lock(&table2->WalkMutex);
+
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);
- mtx_unlock(&table2->WalkMutex);
+}
+
+
+void
+_mesa_HashWalk(const struct _mesa_HashTable *table,
+ void (*callback)(GLuint key, void *data, void *userData),
+ void *userData)
+{
+ /* cast-away const */
+ struct _mesa_HashTable *table2 = (struct _mesa_HashTable *) table;
+
+ _mesa_HashLockMutex(table2);
+ hash_walk_unlocked(table, callback, userData);
+ _mesa_HashUnlockMutex(table2);
+}
+
+void
+_mesa_HashWalkLocked(const struct _mesa_HashTable *table,
+ void (*callback)(GLuint key, void *data, void *userData),
+ void *userData)
+{
+ hash_walk_unlocked(table, callback, userData);
}
static void
_mesa_HashFindFreeKeyBlock(struct _mesa_HashTable *table, GLuint numKeys)
{
const GLuint maxKey = ~((GLuint) 0) - 1;
- mtx_lock(&table->Mutex);
if (maxKey - numKeys > table->MaxKey) {
/* the quick solution */
- mtx_unlock(&table->Mutex);
return table->MaxKey + 1;
}
else {
/* this key not in use, check if we've found enough */
freeCount++;
if (freeCount == numKeys) {
- mtx_unlock(&table->Mutex);
return freeStart;
}
}
}
/* cannot allocate a block of numKeys consecutive keys */
- mtx_unlock(&table->Mutex);
return 0;
}
}
GLuint
_mesa_HashNumEntries(const struct _mesa_HashTable *table)
{
- struct hash_entry *entry;
GLuint count = 0;
if (table->deleted_key_data)
count++;
- hash_table_foreach(table->ht, entry)
- count++;
+ count += _mesa_hash_table_num_entries(table->ht);
return count;
}