pb_bufmgr_cache.c revision 4b52f4df1b37918a363d05e0b3db22125e801367 
1/**************************************************************************
2 *
3 * Copyright 2007-2008 Tungsten Graphics, Inc., Cedar Park, Texas.
4 * All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
16 * of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
21 * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
22 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
23 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
24 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
25 *
26 **************************************************************************/
27
28/**
29 * \file
30 * Buffer cache.
31 *
32 * \author José Fonseca <jrfonseca-at-tungstengraphics-dot-com>
33 * \author Thomas Hellström <thomas-at-tungstengraphics-dot-com>
34 */
35
36
37#include "pipe/p_compiler.h"
38#include "pipe/p_debug.h"
39#include "pipe/p_winsys.h"
40#include "pipe/p_thread.h"
41#include "pipe/p_util.h"
42#include "util/u_double_list.h"
43#include "util/u_time.h"
44
45#include "pb_buffer.h"
46#include "pb_bufmgr.h"
47
48
49/**
50 * Convenience macro (type safe).
51 */
52#define SUPER(__derived) (&(__derived)->base)
53
54
55struct pb_cache_manager;
56
57
58/**
59 * Wrapper around a pipe buffer which adds delayed destruction.
60 */
61struct pb_cache_buffer
62{
63   struct pb_buffer base;
64
65   struct pb_buffer *buffer;
66   struct pb_cache_manager *mgr;
67
68   /** Caching time interval */
69   struct util_time start, end;
70
71   struct list_head head;
72};
73
74
75struct pb_cache_manager
76{
77   struct pb_manager base;
78
79   struct pb_manager *provider;
80   unsigned usecs;
81
82   _glthread_Mutex mutex;
83
84   struct list_head delayed;
85   size_t numDelayed;
86};
87
88
89static INLINE struct pb_cache_buffer *
90pb_cache_buffer(struct pb_buffer *buf)
91{
92   assert(buf);
93   return (struct pb_cache_buffer *)buf;
94}
95
96
97static INLINE struct pb_cache_manager *
98pb_cache_manager(struct pb_manager *mgr)
99{
100   assert(mgr);
101   return (struct pb_cache_manager *)mgr;
102}
103
104
105/**
106 * Actually destroy the buffer.
107 */
108static INLINE void
109_pb_cache_buffer_destroy(struct pb_cache_buffer *buf)
110{
111   struct pb_cache_manager *mgr = buf->mgr;
112
113   LIST_DEL(&buf->head);
114   assert(mgr->numDelayed);
115   --mgr->numDelayed;
116   assert(!buf->base.base.refcount);
117   pb_reference(&buf->buffer, NULL);
118   FREE(buf);
119}
120
121
122/**
123 * Free as many cache buffers from the list head as possible.
124 */
125static void
126_pb_cache_buffer_list_check_free(struct pb_cache_manager *mgr)
127{
128   struct list_head *curr, *next;
129   struct pb_cache_buffer *buf;
130   struct util_time now;
131
132   util_time_get(&now);
133
134   curr = mgr->delayed.next;
135   next = curr->next;
136   while(curr != &mgr->delayed) {
137      buf = LIST_ENTRY(struct pb_cache_buffer, curr, head);
138
139      if(!util_time_timeout(&buf->start, &buf->end, &now))
140	 break;
141
142      _pb_cache_buffer_destroy(buf);
143
144      curr = next;
145      next = curr->next;
146   }
147}
148
149
150static void
151pb_cache_buffer_destroy(struct pb_buffer *_buf)
152{
153   struct pb_cache_buffer *buf = pb_cache_buffer(_buf);
154   struct pb_cache_manager *mgr = buf->mgr;
155
156   _glthread_LOCK_MUTEX(mgr->mutex);
157   assert(buf->base.base.refcount == 0);
158
159   _pb_cache_buffer_list_check_free(mgr);
160
161   util_time_get(&buf->start);
162   util_time_add(&buf->start, mgr->usecs, &buf->end);
163   LIST_ADDTAIL(&buf->head, &mgr->delayed);
164   ++mgr->numDelayed;
165   _glthread_UNLOCK_MUTEX(mgr->mutex);
166}
167
168
169static void *
170pb_cache_buffer_map(struct pb_buffer *_buf,
171                  unsigned flags)
172{
173   struct pb_cache_buffer *buf = pb_cache_buffer(_buf);
174   return pb_map(buf->buffer, flags);
175}
176
177
178static void
179pb_cache_buffer_unmap(struct pb_buffer *_buf)
180{
181   struct pb_cache_buffer *buf = pb_cache_buffer(_buf);
182   pb_unmap(buf->buffer);
183}
184
185
186static void
187pb_cache_buffer_get_base_buffer(struct pb_buffer *_buf,
188                              struct pb_buffer **base_buf,
189                              unsigned *offset)
190{
191   struct pb_cache_buffer *buf = pb_cache_buffer(_buf);
192   pb_get_base_buffer(buf->buffer, base_buf, offset);
193}
194
195
196const struct pb_vtbl
197pb_cache_buffer_vtbl = {
198      pb_cache_buffer_destroy,
199      pb_cache_buffer_map,
200      pb_cache_buffer_unmap,
201      pb_cache_buffer_get_base_buffer
202};
203
204
205static INLINE boolean
206pb_cache_is_buffer_compat(struct pb_cache_buffer *buf,
207                          size_t size,
208                          const struct pb_desc *desc)
209{
210   if(buf->base.base.size < size)
211      return FALSE;
212
213   /* be lenient with size */
214   if(buf->base.base.size >= 2*size)
215      return FALSE;
216
217   if(!pb_check_alignment(desc->alignment, buf->base.base.alignment))
218      return FALSE;
219
220   /* XXX: check usage too? */
221
222   return TRUE;
223}
224
225
226static struct pb_buffer *
227pb_cache_manager_create_buffer(struct pb_manager *_mgr,
228                               size_t size,
229                               const struct pb_desc *desc)
230{
231   struct pb_cache_manager *mgr = pb_cache_manager(_mgr);
232   struct pb_cache_buffer *buf;
233   struct pb_cache_buffer *curr_buf;
234   struct list_head *curr, *next;
235   struct util_time now;
236
237   _glthread_LOCK_MUTEX(mgr->mutex);
238
239   buf = NULL;
240   curr = mgr->delayed.next;
241   next = curr->next;
242
243   /* search in the expired buffers, freeing them in the process */
244   util_time_get(&now);
245   while(curr != &mgr->delayed) {
246      curr_buf = LIST_ENTRY(struct pb_cache_buffer, curr, head);
247      if(!buf && pb_cache_is_buffer_compat(curr_buf, size, desc))
248	 buf = curr_buf;
249      else if(util_time_timeout(&curr_buf->start, &curr_buf->end, &now))
250	 _pb_cache_buffer_destroy(curr_buf);
251      curr = next;
252      next = curr->next;
253   }
254
255   /* keep searching in the hot buffers */
256   while(!buf && curr != &mgr->delayed) {
257      curr_buf = LIST_ENTRY(struct pb_cache_buffer, curr, head);
258      if(pb_cache_is_buffer_compat(curr_buf, size, desc))
259	 buf = curr_buf;
260      curr = next;
261      next = curr->next;
262   }
263
264   if(buf) {
265      LIST_DEL(&buf->head);
266      _glthread_UNLOCK_MUTEX(mgr->mutex);
267      ++buf->base.base.refcount;
268      return &buf->base;
269   }
270
271   _glthread_UNLOCK_MUTEX(mgr->mutex);
272
273   buf = CALLOC_STRUCT(pb_cache_buffer);
274   if(!buf)
275      return NULL;
276
277   buf->buffer = mgr->provider->create_buffer(mgr->provider, size, desc);
278   if(!buf->buffer) {
279      FREE(buf);
280      return NULL;
281   }
282
283   assert(buf->buffer->base.refcount >= 1);
284   assert(pb_check_alignment(desc->alignment, buf->buffer->base.alignment));
285   assert((buf->buffer->base.usage & desc->usage) == desc->usage);
286   assert(buf->buffer->base.size >= size);
287
288   buf->base.base.refcount = 1;
289   buf->base.base.alignment = buf->buffer->base.alignment;
290   buf->base.base.usage = buf->buffer->base.usage;
291   buf->base.base.size = buf->buffer->base.size;
292
293   buf->base.vtbl = &pb_cache_buffer_vtbl;
294   buf->mgr = mgr;
295
296   return &buf->base;
297}
298
299
300void
301pb_cache_flush(struct pb_manager *_mgr)
302{
303   struct pb_cache_manager *mgr = pb_cache_manager(_mgr);
304   struct list_head *curr, *next;
305   struct pb_cache_buffer *buf;
306
307   _glthread_LOCK_MUTEX(mgr->mutex);
308   curr = mgr->delayed.next;
309   next = curr->next;
310   while(curr != &mgr->delayed) {
311      buf = LIST_ENTRY(struct pb_cache_buffer, curr, head);
312      _pb_cache_buffer_destroy(buf);
313      curr = next;
314      next = curr->next;
315   }
316   _glthread_UNLOCK_MUTEX(mgr->mutex);
317}
318
319
320static void
321pb_cache_manager_destroy(struct pb_manager *mgr)
322{
323   pb_cache_flush(mgr);
324   FREE(mgr);
325}
326
327
328struct pb_manager *
329pb_cache_manager_create(struct pb_manager *provider,
330                     	unsigned usecs)
331{
332   struct pb_cache_manager *mgr;
333
334   mgr = (struct pb_cache_manager *)CALLOC(1, sizeof(*mgr));
335   if (!mgr)
336      return NULL;
337
338   mgr->base.destroy = pb_cache_manager_destroy;
339   mgr->base.create_buffer = pb_cache_manager_create_buffer;
340   mgr->provider = provider;
341   mgr->usecs = usecs;
342   LIST_INITHEAD(&mgr->delayed);
343   mgr->numDelayed = 0;
344   _glthread_INIT_MUTEX(mgr->mutex);
345
346   return &mgr->base;
347}
348