etnaviv_bo_cache.c revision 00a23bda 
1/*
2 * Copyright (C) 2016 Etnaviv Project
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
21 * SOFTWARE.
22 *
23 * Authors:
24 *    Christian Gmeiner <christian.gmeiner@gmail.com>
25 */
26
27#ifdef HAVE_CONFIG_H
28# include <config.h>
29#endif
30
31#include "etnaviv_priv.h"
32#include "etnaviv_drmif.h"
33
34drm_private void bo_del(struct etna_bo *bo);
35drm_private extern pthread_mutex_t table_lock;
36
37static void add_bucket(struct etna_bo_cache *cache, int size)
38{
39	unsigned i = cache->num_buckets;
40
41	assert(i < ARRAY_SIZE(cache->cache_bucket));
42
43	list_inithead(&cache->cache_bucket[i].list);
44	cache->cache_bucket[i].size = size;
45	cache->num_buckets++;
46}
47
48drm_private void etna_bo_cache_init(struct etna_bo_cache *cache)
49{
50	unsigned long size, cache_max_size = 64 * 1024 * 1024;
51
52	/* OK, so power of two buckets was too wasteful of memory.
53	 * Give 3 other sizes between each power of two, to hopefully
54	 * cover things accurately enough.  (The alternative is
55	 * probably to just go for exact matching of sizes, and assume
56	 * that for things like composited window resize the tiled
57	 * width/height alignment and rounding of sizes to pages will
58	 * get us useful cache hit rates anyway)
59	 */
60	add_bucket(cache, 4096);
61	add_bucket(cache, 4096 * 2);
62	add_bucket(cache, 4096 * 3);
63
64	/* Initialize the linked lists for BO reuse cache. */
65	for (size = 4 * 4096; size <= cache_max_size; size *= 2) {
66		add_bucket(cache, size);
67		add_bucket(cache, size + size * 1 / 4);
68		add_bucket(cache, size + size * 2 / 4);
69		add_bucket(cache, size + size * 3 / 4);
70	}
71}
72
73/* Frees older cached buffers.  Called under table_lock */
74drm_private void etna_bo_cache_cleanup(struct etna_bo_cache *cache, time_t time)
75{
76	unsigned i;
77
78	if (cache->time == time)
79		return;
80
81	for (i = 0; i < cache->num_buckets; i++) {
82		struct etna_bo_bucket *bucket = &cache->cache_bucket[i];
83		struct etna_bo *bo;
84
85		while (!LIST_IS_EMPTY(&bucket->list)) {
86			bo = LIST_ENTRY(struct etna_bo, bucket->list.next, list);
87
88			/* keep things in cache for at least 1 second: */
89			if (time && ((time - bo->free_time) <= 1))
90				break;
91
92			list_del(&bo->list);
93			bo_del(bo);
94		}
95	}
96
97	cache->time = time;
98}
99
100static struct etna_bo_bucket *get_bucket(struct etna_bo_cache *cache, uint32_t size)
101{
102	unsigned i;
103
104	/* hmm, this is what intel does, but I suppose we could calculate our
105	 * way to the correct bucket size rather than looping..
106	 */
107	for (i = 0; i < cache->num_buckets; i++) {
108		struct etna_bo_bucket *bucket = &cache->cache_bucket[i];
109		if (bucket->size >= size) {
110			return bucket;
111		}
112	}
113
114	return NULL;
115}
116
117static int is_idle(struct etna_bo *bo)
118{
119	return etna_bo_cpu_prep(bo,
120			DRM_ETNA_PREP_READ |
121			DRM_ETNA_PREP_WRITE |
122			DRM_ETNA_PREP_NOSYNC) == 0;
123}
124
125static struct etna_bo *find_in_bucket(struct etna_bo_bucket *bucket, uint32_t flags)
126{
127	struct etna_bo *bo = NULL, *tmp;
128
129	pthread_mutex_lock(&table_lock);
130
131	if (LIST_IS_EMPTY(&bucket->list))
132		goto out_unlock;
133
134	LIST_FOR_EACH_ENTRY_SAFE(bo, tmp, &bucket->list, list) {
135		/* skip BOs with different flags */
136		if (bo->flags != flags)
137			continue;
138
139		/* check if the first BO with matching flags is idle */
140		if (is_idle(bo)) {
141			list_delinit(&bo->list);
142			goto out_unlock;
143		}
144
145		/* If the oldest BO is still busy, don't try younger ones */
146		break;
147	}
148
149	/* There was no matching buffer found */
150	bo = NULL;
151
152out_unlock:
153	pthread_mutex_unlock(&table_lock);
154
155	return bo;
156}
157
158/* allocate a new (un-tiled) buffer object
159 *
160 * NOTE: size is potentially rounded up to bucket size
161 */
162drm_private struct etna_bo *etna_bo_cache_alloc(struct etna_bo_cache *cache, uint32_t *size,
163    uint32_t flags)
164{
165	struct etna_bo *bo;
166	struct etna_bo_bucket *bucket;
167
168	*size = ALIGN(*size, 4096);
169	bucket = get_bucket(cache, *size);
170
171	/* see if we can be green and recycle: */
172	if (bucket) {
173		*size = bucket->size;
174		bo = find_in_bucket(bucket, flags);
175		if (bo) {
176			atomic_set(&bo->refcnt, 1);
177			etna_device_ref(bo->dev);
178			return bo;
179		}
180	}
181
182	return NULL;
183}
184
185drm_private int etna_bo_cache_free(struct etna_bo_cache *cache, struct etna_bo *bo)
186{
187	struct etna_bo_bucket *bucket = get_bucket(cache, bo->size);
188
189	/* see if we can be green and recycle: */
190	if (bucket) {
191		struct timespec time;
192
193		clock_gettime(CLOCK_MONOTONIC, &time);
194
195		bo->free_time = time.tv_sec;
196		list_addtail(&bo->list, &bucket->list);
197		etna_bo_cache_cleanup(cache, time.tv_sec);
198
199		/* bo's in the bucket cache don't have a ref and
200		 * don't hold a ref to the dev:
201		 */
202		etna_device_del_locked(bo->dev);
203
204		return 0;
205	}
206
207	return -1;
208}
209