src/gallium/drivers/svga/svga_screen_cache.c

   1 /**********************************************************
   2  * Copyright 2008-2009 VMware, Inc.  All rights reserved.
   3  *
   4  * Permission is hereby granted, free of charge, to any person
   5  * obtaining a copy of this software and associated documentation
   6  * files (the "Software"), to deal in the Software without
   7  * restriction, including without limitation the rights to use, copy,
   8  * modify, merge, publish, distribute, sublicense, and/or sell copies
   9  * of the Software, and to permit persons to whom the Software is
  10  * furnished to do so, subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice shall be
  13  * included in all copies or substantial portions of the Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  16  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  17  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  18  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  19  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  20  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  21  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  22  * SOFTWARE.
  23  *
  24  **********************************************************/
  25
  26 #include "util/u_math.h"
  27 #include "util/u_memory.h"
  28 #include "util/u_hash.h"
  29
  30 #include "svga_debug.h"
  31 #include "svga_format.h"
  32 #include "svga_winsys.h"
  33 #include "svga_screen.h"
  34 #include "svga_screen_cache.h"
  35
  36
  37 #define SVGA_SURFACE_CACHE_ENABLED 1
  38
  39
  40 /**
  41  * Return the size of the surface described by the key (in bytes).
  42  */
  43 static unsigned
  44 surface_size(const struct svga_host_surface_cache_key *key)
  45 {
  46    unsigned bw, bh, bpb, total_size, i;
  47
  48    assert(key->numMipLevels > 0);
  49    assert(key->numFaces > 0);
  50
  51    if (key->format == SVGA3D_BUFFER) {
  52       /* Special case: we don't want to count vertex/index buffers
  53        * against the cache size limit, so view them as zero-sized.
  54        */
  55       return 0;
  56    }
  57
  58    svga_format_size(key->format, &bw, &bh, &bpb);
  59
  60    total_size = 0;
  61
  62    for (i = 0; i < key->numMipLevels; i++) {
  63       unsigned w = u_minify(key->size.width, i);
  64       unsigned h = u_minify(key->size.height, i);
  65       unsigned d = u_minify(key->size.depth, i);
  66       unsigned img_size = ((w + bw - 1) / bw) * ((h + bh - 1) / bh) * d * bpb;
  67       total_size += img_size;
  68    }
  69
  70    total_size *= key->numFaces;
  71
  72    return total_size;
  73 }
  74
  75
  76 /**
  77  * Compute the bucket for this key.
  78  */
  79 static INLINE unsigned
  80 svga_screen_cache_bucket(const struct svga_host_surface_cache_key *key)
  81 {
  82    return util_hash_crc32(key, sizeof *key) % SVGA_HOST_SURFACE_CACHE_BUCKETS;
  83 }
  84
  85
  86 /**
  87  * Search the cache for a surface that matches the key.  If a match is
  88  * found, remove it from the cache and return the surface pointer.
  89  * Return NULL otherwise.
  90  */
  91 static INLINE struct svga_winsys_surface *
  92 svga_screen_cache_lookup(struct svga_screen *svgascreen,
  93                          const struct svga_host_surface_cache_key *key)
  94 {
  95    struct svga_host_surface_cache *cache = &svgascreen->cache;
  96    struct svga_winsys_screen *sws = svgascreen->sws;
  97    struct svga_host_surface_cache_entry *entry;
  98    struct svga_winsys_surface *handle = NULL;
  99    struct list_head *curr, *next;
 100    unsigned bucket;
 101    unsigned tries = 0;
 102
 103    assert(key->cachable);
 104
 105    bucket = svga_screen_cache_bucket(key);
 106
 107    pipe_mutex_lock(cache->mutex);
 108
 109    curr = cache->bucket[bucket].next;
 110    next = curr->next;
 111    while (curr != &cache->bucket[bucket]) {
 112       ++tries;
 113
 114       entry = LIST_ENTRY(struct svga_host_surface_cache_entry, curr, bucket_head);
 115
 116       assert(entry->handle);
 117
 118       if (memcmp(&entry->key, key, sizeof *key) == 0 &&
 119          sws->fence_signalled(sws, entry->fence, 0) == 0) {
 120          unsigned surf_size;
 121
 122          assert(sws->surface_is_flushed(sws, entry->handle));
 123
 124          handle = entry->handle; /* Reference is transfered here. */
 125          entry->handle = NULL;
 126
 127          LIST_DEL(&entry->bucket_head);
 128
 129          LIST_DEL(&entry->head);
 130
 131          LIST_ADD(&entry->head, &cache->empty);
 132
 133          /* update the cache size */
 134          surf_size = surface_size(&entry->key);
 135          assert(surf_size <= cache->total_size);
 136          if (surf_size > cache->total_size)
 137             cache->total_size = 0; /* should never happen, but be safe */
 138          else
 139             cache->total_size -= surf_size;
 140
 141          break;
 142       }
 143
 144       curr = next;
 145       next = curr->next;
 146    }
 147
 148    pipe_mutex_unlock(cache->mutex);
 149
 150    if (SVGA_DEBUG & DEBUG_DMA)
 151       debug_printf("%s: cache %s after %u tries (bucket %d)\n", __FUNCTION__,
 152                    handle ? "hit" : "miss", tries, bucket);
 153
 154    return handle;
 155 }
 156
 157
 158 /**
 159  * Free the least recently used entries in the surface cache until the
 160  * cache size is <= the target size OR there are no unused entries left
 161  * to discard.  We don't do any flushing to try to free up additional
 162  * surfaces.
 163  */
 164 static void
 165 svga_screen_cache_shrink(struct svga_screen *svgascreen,
 166                          unsigned target_size)
 167 {
 168    struct svga_host_surface_cache *cache = &svgascreen->cache;
 169    struct svga_winsys_screen *sws = svgascreen->sws;
 170    struct svga_host_surface_cache_entry *entry = NULL, *next_entry;
 171
 172    /* Walk over the list of unused buffers in reverse order: from oldest
 173     * to newest.
 174     */
 175    LIST_FOR_EACH_ENTRY_SAFE_REV(entry, next_entry, &cache->unused, head) {
 176       if (entry->key.format != SVGA3D_BUFFER) {
 177          /* we don't want to discard vertex/index buffers */
 178
 179          cache->total_size -= surface_size(&entry->key);
 180
 181          assert(entry->handle);
 182          sws->surface_reference(sws, &entry->handle, NULL);
 183
 184          LIST_DEL(&entry->bucket_head);
 185          LIST_DEL(&entry->head);
 186          LIST_ADD(&entry->head, &cache->empty);
 187
 188          if (cache->total_size <= target_size) {
 189             /* all done */
 190             break;
 191          }
 192       }
 193    }
 194 }
 195
 196
 197 /**
 198  * Transfers a handle reference.
 199  */
 200 static INLINE void
 201 svga_screen_cache_add(struct svga_screen *svgascreen,
 202                       const struct svga_host_surface_cache_key *key,
 203                       struct svga_winsys_surface **p_handle)
 204 {
 205    struct svga_host_surface_cache *cache = &svgascreen->cache;
 206    struct svga_winsys_screen *sws = svgascreen->sws;
 207    struct svga_host_surface_cache_entry *entry = NULL;
 208    struct svga_winsys_surface *handle = *p_handle;
 209    unsigned surf_size;
 210
 211    assert(key->cachable);
 212
 213    assert(handle);
 214    if (!handle)
 215       return;
 216
 217    surf_size = surface_size(key);
 218
 219    *p_handle = NULL;
 220    pipe_mutex_lock(cache->mutex);
 221
 222    if (surf_size >= SVGA_HOST_SURFACE_CACHE_BYTES) {
 223       /* this surface is too large to cache, just free it */
 224       sws->surface_reference(sws, &handle, NULL);
 225       pipe_mutex_unlock(cache->mutex);
 226       return;
 227    }
 228
 229    if (cache->total_size + surf_size > SVGA_HOST_SURFACE_CACHE_BYTES) {
 230       /* Adding this surface would exceed the cache size.
 231        * Try to discard least recently used entries until we hit the
 232        * new target cache size.
 233        */
 234       unsigned target_size = SVGA_HOST_SURFACE_CACHE_BYTES - surf_size;
 235
 236       svga_screen_cache_shrink(svgascreen, target_size);
 237
 238       if (cache->total_size > target_size) {
 239          /* we weren't able to shrink the cache as much as we wanted so
 240           * just discard this surface.
 241           */
 242          sws->surface_reference(sws, &handle, NULL);
 243          pipe_mutex_unlock(cache->mutex);
 244          return;
 245       }
 246    }
 247
 248    if (!LIST_IS_EMPTY(&cache->empty)) {
 249       /* use the first empty entry */
 250       entry = LIST_ENTRY(struct svga_host_surface_cache_entry,
 251                          cache->empty.next, head);
 252
 253       LIST_DEL(&entry->head);
 254    }
 255    else if (!LIST_IS_EMPTY(&cache->unused)) {
 256       /* free the last used buffer and reuse its entry */
 257       entry = LIST_ENTRY(struct svga_host_surface_cache_entry,
 258                          cache->unused.prev, head);
 259       SVGA_DBG(DEBUG_CACHE|DEBUG_DMA,
 260                "unref sid %p (make space)\n", entry->handle);
 261
 262       cache->total_size -= surface_size(&entry->key);
 263
 264       sws->surface_reference(sws, &entry->handle, NULL);
 265
 266       LIST_DEL(&entry->bucket_head);
 267
 268       LIST_DEL(&entry->head);
 269    }
 270
 271    if (entry) {
 272       entry->handle = handle;
 273       memcpy(&entry->key, key, sizeof entry->key);
 274
 275       SVGA_DBG(DEBUG_CACHE|DEBUG_DMA,
 276                "cache sid %p\n", entry->handle);
 277       LIST_ADD(&entry->head, &cache->validated);
 278
 279       cache->total_size += surf_size;
 280    }
 281    else {
 282       /* Couldn't cache the buffer -- this really shouldn't happen */
 283       SVGA_DBG(DEBUG_CACHE|DEBUG_DMA,
 284                "unref sid %p (couldn't find space)\n", handle);
 285       sws->surface_reference(sws, &handle, NULL);
 286    }
 287
 288    pipe_mutex_unlock(cache->mutex);
 289 }
 290
 291
 292 /**
 293  * Called during the screen flush to move all buffers not in a validate list
 294  * into the unused list.
 295  */
 296 void
 297 svga_screen_cache_flush(struct svga_screen *svgascreen,
 298                         struct pipe_fence_handle *fence)
 299 {
 300    struct svga_host_surface_cache *cache = &svgascreen->cache;
 301    struct svga_winsys_screen *sws = svgascreen->sws;
 302    struct svga_host_surface_cache_entry *entry;
 303    struct list_head *curr, *next;
 304    unsigned bucket;
 305
 306    pipe_mutex_lock(cache->mutex);
 307
 308    curr = cache->validated.next;
 309    next = curr->next;
 310    while (curr != &cache->validated) {
 311       entry = LIST_ENTRY(struct svga_host_surface_cache_entry, curr, head);
 312
 313       assert(entry->handle);
 314
 315       if (sws->surface_is_flushed(sws, entry->handle)) {
 316          LIST_DEL(&entry->head);
 317
 318          svgascreen->sws->fence_reference(svgascreen->sws, &entry->fence, fence);
 319
 320          LIST_ADD(&entry->head, &cache->unused);
 321
 322          bucket = svga_screen_cache_bucket(&entry->key);
 323          LIST_ADD(&entry->bucket_head, &cache->bucket[bucket]);
 324       }
 325
 326       curr = next;
 327       next = curr->next;
 328    }
 329
 330    pipe_mutex_unlock(cache->mutex);
 331 }
 332
 333
 334 /**
 335  * Free all the surfaces in the cache.
 336  * Called when destroying the svga screen object.
 337  */
 338 void
 339 svga_screen_cache_cleanup(struct svga_screen *svgascreen)
 340 {
 341    struct svga_host_surface_cache *cache = &svgascreen->cache;
 342    struct svga_winsys_screen *sws = svgascreen->sws;
 343    unsigned i;
 344
 345    for (i = 0; i < SVGA_HOST_SURFACE_CACHE_SIZE; ++i) {
 346       if (cache->entries[i].handle) {
 347          SVGA_DBG(DEBUG_CACHE|DEBUG_DMA,
 348                   "unref sid %p (shutdown)\n", cache->entries[i].handle);
 349          sws->surface_reference(sws, &cache->entries[i].handle, NULL);
 350
 351          cache->total_size -= surface_size(&cache->entries[i].key);
 352       }
 353
 354       if (cache->entries[i].fence)
 355          svgascreen->sws->fence_reference(svgascreen->sws,
 356                                           &cache->entries[i].fence, NULL);
 357    }
 358
 359    pipe_mutex_destroy(cache->mutex);
 360 }
 361
 362
 363 enum pipe_error
 364 svga_screen_cache_init(struct svga_screen *svgascreen)
 365 {
 366    struct svga_host_surface_cache *cache = &svgascreen->cache;
 367    unsigned i;
 368
 369    assert(cache->total_size == 0);
 370
 371    pipe_mutex_init(cache->mutex);
 372
 373    for (i = 0; i < SVGA_HOST_SURFACE_CACHE_BUCKETS; ++i)
 374       LIST_INITHEAD(&cache->bucket[i]);
 375
 376    LIST_INITHEAD(&cache->unused);
 377
 378    LIST_INITHEAD(&cache->validated);
 379
 380    LIST_INITHEAD(&cache->empty);
 381    for (i = 0; i < SVGA_HOST_SURFACE_CACHE_SIZE; ++i)
 382       LIST_ADDTAIL(&cache->entries[i].head, &cache->empty);
 383
 384    return PIPE_OK;
 385 }
 386
 387
 388 /**
 389  * Allocate a new host-side surface.  If the surface is marked as cachable,
 390  * first try re-using a surface in the cache of freed surfaces.  Otherwise,
 391  * allocate a new surface.
 392  */
 393 struct svga_winsys_surface *
 394 svga_screen_surface_create(struct svga_screen *svgascreen,
 395                            struct svga_host_surface_cache_key *key)
 396 {
 397    struct svga_winsys_screen *sws = svgascreen->sws;
 398    struct svga_winsys_surface *handle = NULL;
 399    boolean cachable = SVGA_SURFACE_CACHE_ENABLED && key->cachable;
 400
 401    SVGA_DBG(DEBUG_CACHE|DEBUG_DMA,
 402             "%s sz %dx%dx%d mips %d faces %d cachable %d\n",
 403             __FUNCTION__,
 404             key->size.width,
 405             key->size.height,
 406             key->size.depth,
 407             key->numMipLevels,
 408             key->numFaces,
 409             key->cachable);
 410
 411    if (cachable) {
 412       if (key->format == SVGA3D_BUFFER) {
 413          /* For buffers, round the buffer size up to the nearest power
 414           * of two to increase the probability of cache hits.  Keep
 415           * texture surface dimensions unchanged.
 416           */
 417          uint32_t size = 1;
 418          while (size < key->size.width)
 419             size <<= 1;
 420          key->size.width = size;
 421          /* Since we're reusing buffers we're effectively transforming all
 422           * of them into dynamic buffers.
 423           *
 424           * It would be nice to not cache long lived static buffers. But there
 425           * is no way to detect the long lived from short lived ones yet. A
 426           * good heuristic would be buffer size.
 427           */
 428          key->flags &= ~SVGA3D_SURFACE_HINT_STATIC;
 429          key->flags |= SVGA3D_SURFACE_HINT_DYNAMIC;
 430       }
 431
 432       handle = svga_screen_cache_lookup(svgascreen, key);
 433       if (handle) {
 434          if (key->format == SVGA3D_BUFFER)
 435             SVGA_DBG(DEBUG_CACHE|DEBUG_DMA,
 436                      "reuse sid %p sz %d (buffer)\n", handle,
 437                      key->size.width);
 438          else
 439             SVGA_DBG(DEBUG_CACHE|DEBUG_DMA,
 440                      "reuse sid %p sz %dx%dx%d mips %d faces %d\n", handle,
 441                      key->size.width,
 442                      key->size.height,
 443                      key->size.depth,
 444                      key->numMipLevels,
 445                      key->numFaces);
 446       }
 447    }
 448
 449    if (!handle) {
 450       handle = sws->surface_create(sws,
 451                                    key->flags,
 452                                    key->format,
 453                                    key->size,
 454                                    key->numFaces,
 455                                    key->numMipLevels);
 456       if (handle)
 457          SVGA_DBG(DEBUG_CACHE|DEBUG_DMA,
 458                   "  CREATE sid %p sz %dx%dx%d\n",
 459                   handle,
 460                   key->size.width,
 461                   key->size.height,
 462                   key->size.depth);
 463    }
 464
 465    return handle;
 466 }
 467
 468
 469 /**
 470  * Release a surface.  We don't actually free the surface- we put
 471  * it into the cache of freed surfaces (if it's cachable).
 472  */
 473 void
 474 svga_screen_surface_destroy(struct svga_screen *svgascreen,
 475                             const struct svga_host_surface_cache_key *key,
 476                             struct svga_winsys_surface **p_handle)
 477 {
 478    struct svga_winsys_screen *sws = svgascreen->sws;
 479
 480    /* We only set the cachable flag for surfaces of which we are the
 481     * exclusive owner.  So just hold onto our existing reference in
 482     * that case.
 483     */
 484    if (SVGA_SURFACE_CACHE_ENABLED && key->cachable) {
 485       svga_screen_cache_add(svgascreen, key, p_handle);
 486    }
 487    else {
 488       SVGA_DBG(DEBUG_DMA,
 489                "unref sid %p (uncachable)\n", *p_handle);
 490       sws->surface_reference(sws, p_handle, NULL);
 491    }
 492 }
 493
 494
 495 /**
 496  * Print/dump the contents of the screen cache.  For debugging.
 497  */
 498 void
 499 svga_screen_cache_dump(const struct svga_screen *svgascreen)
 500 {
 501    const struct svga_host_surface_cache *cache = &svgascreen->cache;
 502    unsigned bucket;
 503    unsigned count = 0;
 504
 505    debug_printf("svga3d surface cache:\n");
 506    for (bucket = 0; bucket < SVGA_HOST_SURFACE_CACHE_BUCKETS; bucket++) {
 507       struct list_head *curr;
 508       curr = cache->bucket[bucket].next;
 509       while (curr && curr != &cache->bucket[bucket]) {
 510          struct svga_host_surface_cache_entry *entry =
 511             LIST_ENTRY(struct svga_host_surface_cache_entry,
 512                        curr, bucket_head);
 513          if (entry->key.format != 37) {
 514             debug_printf("  %u x %u x %u format %u\n",
 515                          entry->key.size.width,
 516                          entry->key.size.height,
 517                          entry->key.size.depth,
 518                          entry->key.format);
 519          }
 520          curr = curr->next;
 521          count++;
 522       }
 523    }
 524
 525    debug_printf("%u surfaces, %u bytes\n", count, cache->total_size);
 526 }