/*
* Cogl
*
* A Low Level GPU Graphics and Utilities API
*
* Copyright (C) 2013 Intel Corporation.
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use, copy,
* modify, merge, publish, distribute, sublicense, and/or sell copies
* of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*
*
* Authors:
* Neil Roberts <neil@linux.intel.com>
* Robert Bragg <robert@linux.intel.com>
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "cogl-context-private.h"
#include "cogl-pipeline-private.h"
#include "cogl-pipeline-hash-table.h"
#include "cogl-pipeline-cache.h"
typedef struct
{
CoglPipelineCacheEntry parent;
/* Calculating the hash is a little bit expensive for pipelines so
* we don't want to do it repeatedly for entries that are already in
* the hash table. Instead we cache the value here and calculate it
* outside of the GHashTable. */
unsigned int hash_value;
/* GHashTable annoyingly doesn't let us pass a user data pointer to
* the hash and equal functions so to work around it we have to
* store the pointer in every hash table entry. We will use this
* entry as both the key and the value */
CoglPipelineHashTable *hash;
/* The number of unique pipelines that had been created when this
* pipeline was last accessed */
int age;
} CoglPipelineHashTableEntry;
static void
value_destroy_cb (void *value)
{
CoglPipelineHashTableEntry *entry = value;
cogl_object_unref (entry->parent.pipeline);
g_slice_free (CoglPipelineHashTableEntry, entry);
}
static unsigned int
entry_hash (const void *data)
{
const CoglPipelineHashTableEntry *entry = data;
return entry->hash_value;
}
static CoglBool
entry_equal (const void *a,
const void *b)
{
const CoglPipelineHashTableEntry *entry_a = a;
const CoglPipelineHashTableEntry *entry_b = b;
const CoglPipelineHashTable *hash = entry_a->hash;
return _cogl_pipeline_equal (entry_a->parent.pipeline,
entry_b->parent.pipeline,
hash->main_state,
hash->layer_state,
0);
}
void
_cogl_pipeline_hash_table_init (CoglPipelineHashTable *hash,
unsigned int main_state,
unsigned int layer_state,
const char *debug_string)
{
hash->n_unique_pipelines = 0;
hash->debug_string = debug_string;
hash->main_state = main_state;
hash->layer_state = layer_state;
/* We'll only start pruning once we get to 16 unique pipelines */
hash->expected_min_size = 8;
hash->table = g_hash_table_new_full (entry_hash,
entry_equal,
NULL, /* key destroy */
value_destroy_cb);
}
void
_cogl_pipeline_hash_table_destroy (CoglPipelineHashTable *hash)
{
g_hash_table_destroy (hash->table);
}
static void
collect_prunable_entries_cb (void *key,
void *value,
void *user_data)
{
GQueue *entries = user_data;
CoglPipelineCacheEntry *entry = value;
if (entry->usage_count == 0)
g_queue_push_tail (entries, entry);
}
static int
compare_pipeline_age_cb (const void *a,
const void *b)
{
const CoglPipelineHashTableEntry *ae = a;
const CoglPipelineHashTableEntry *be = b;
return be->age - ae->age;
}
static void
prune_old_pipelines (CoglPipelineHashTable *hash)
{
GQueue entries;
GList *l;
int i;
/* Collect all of the prunable entries into a GQueue */
g_queue_init (&entries);
g_hash_table_foreach (hash->table,
collect_prunable_entries_cb,
&entries);
/* Sort the entries by increasing order of age */
entries.head = g_list_sort (entries.head, compare_pipeline_age_cb);
/* The +1 is to include the pipeline that we're about to add */
hash->expected_min_size = (g_hash_table_size (hash->table) -
entries.length +
1);
/* Remove oldest half of the prunable pipelines. We still want to
* keep some of the prunable entries that are recently used because
* it's not unlikely that the application will recreate the same
* pipeline */
for (l = entries.head, i = 0; i < entries.length / 2; l = l->next, i++)
{
CoglPipelineCacheEntry *entry = l->data;
g_hash_table_remove (hash->table, entry);
}
g_list_free (entries.head);
}
CoglPipelineCacheEntry *
_cogl_pipeline_hash_table_get (CoglPipelineHashTable *hash,
CoglPipeline *key_pipeline)
{
CoglPipelineHashTableEntry dummy_entry;
CoglPipelineHashTableEntry *entry;
unsigned int copy_state;
dummy_entry.parent.pipeline = key_pipeline;
dummy_entry.hash = hash;
dummy_entry.hash_value = _cogl_pipeline_hash (key_pipeline,
hash->main_state,
hash->layer_state,
0);
entry = g_hash_table_lookup (hash->table, &dummy_entry);
if (entry)
{
entry->age = hash->n_unique_pipelines;
return &entry->parent;
}
if (hash->n_unique_pipelines == 50)
g_warning ("Over 50 separate %s have been generated which is very "
"unusual, so something is probably wrong!\n",
hash->debug_string);
/* If we are going to have more than twice the expected minimum
* number of pipelines in the hash then we'll try pruning and update
* the minimum */
if (g_hash_table_size (hash->table) >= hash->expected_min_size * 2)
prune_old_pipelines (hash);
entry = g_slice_new (CoglPipelineHashTableEntry);
entry->parent.usage_count = 0;
entry->hash = hash;
entry->hash_value = dummy_entry.hash_value;
entry->age = hash->n_unique_pipelines;
copy_state = hash->main_state;
if (hash->layer_state)
copy_state |= COGL_PIPELINE_STATE_LAYERS;
/* Create a new pipeline that is a child of the root pipeline
* instead of a normal copy so that the template pipeline won't hold
* a reference to the original pipeline */
entry->parent.pipeline = _cogl_pipeline_deep_copy (key_pipeline,
copy_state,
hash->layer_state);
g_hash_table_insert (hash->table, entry, entry);
hash->n_unique_pipelines++;
return &entry->parent;
}