1 /*
2 Copyright (C) Intel Corp. 2006. All Rights Reserved.
3 Intel funded Tungsten Graphics (http://www.tungstengraphics.com) to
4 develop this 3D driver.
5
6 Permission is hereby granted, free of charge, to any person obtaining
7 a 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, sublicense, 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
16 portions of the Software.
17
18 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
19 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
21 IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
22 LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
23 OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
24 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
25
26 **********************************************************************/
27 /*
28 * Authors:
29 * Keith Whitwell <keith@tungstengraphics.com>
30 */
31
32 /** @file brw_state_cache.c
33 *
34 * This file implements a simple static state cache for 965. The
35 * consumers can query the hash table of state using a cache_id,
36 * opaque key data, and receive the corresponding state buffer object
37 * of state (plus associated auxiliary data) in return. Objects in
38 * the cache may not have relocations (pointers to other BOs) in them.
39 *
40 * The inner workings are a simple hash table based on a CRC of the
41 * key data.
42 *
43 * Replacement is not implemented. Instead, when the cache gets too
44 * big we throw out all of the cache data and let it get regenerated.
45 */
46
47 #include "main/imports.h"
48 #include "intel_batchbuffer.h"
49 #include "brw_state.h"
50
51 #define FILE_DEBUG_FLAG DEBUG_STATE
52
53 static GLuint
hash_key(struct brw_cache_item * item)54 hash_key(struct brw_cache_item *item)
55 {
56 GLuint *ikey = (GLuint *)item->key;
57 GLuint hash = item->cache_id, i;
58
59 assert(item->key_size % 4 == 0);
60
61 /* I'm sure this can be improved on:
62 */
63 for (i = 0; i < item->key_size/4; i++) {
64 hash ^= ikey[i];
65 hash = (hash << 5) | (hash >> 27);
66 }
67
68 return hash;
69 }
70
71 static int
brw_cache_item_equals(const struct brw_cache_item * a,const struct brw_cache_item * b)72 brw_cache_item_equals(const struct brw_cache_item *a,
73 const struct brw_cache_item *b)
74 {
75 return a->cache_id == b->cache_id &&
76 a->hash == b->hash &&
77 a->key_size == b->key_size &&
78 (memcmp(a->key, b->key, a->key_size) == 0);
79 }
80
81 static struct brw_cache_item *
search_cache(struct brw_cache * cache,GLuint hash,struct brw_cache_item * lookup)82 search_cache(struct brw_cache *cache, GLuint hash,
83 struct brw_cache_item *lookup)
84 {
85 struct brw_cache_item *c;
86
87 #if 0
88 int bucketcount = 0;
89
90 for (c = cache->items[hash % cache->size]; c; c = c->next)
91 bucketcount++;
92
93 fprintf(stderr, "bucket %d/%d = %d/%d items\n", hash % cache->size,
94 cache->size, bucketcount, cache->n_items);
95 #endif
96
97 for (c = cache->items[hash % cache->size]; c; c = c->next) {
98 if (brw_cache_item_equals(lookup, c))
99 return c;
100 }
101
102 return NULL;
103 }
104
105
106 static void
rehash(struct brw_cache * cache)107 rehash(struct brw_cache *cache)
108 {
109 struct brw_cache_item **items;
110 struct brw_cache_item *c, *next;
111 GLuint size, i;
112
113 size = cache->size * 3;
114 items = (struct brw_cache_item**) calloc(1, size * sizeof(*items));
115
116 for (i = 0; i < cache->size; i++)
117 for (c = cache->items[i]; c; c = next) {
118 next = c->next;
119 c->next = items[c->hash % size];
120 items[c->hash % size] = c;
121 }
122
123 FREE(cache->items);
124 cache->items = items;
125 cache->size = size;
126 }
127
128
129 /**
130 * Returns the buffer object matching cache_id and key, or NULL.
131 */
132 bool
brw_search_cache(struct brw_cache * cache,enum brw_cache_id cache_id,const void * key,GLuint key_size,uint32_t * inout_offset,void * out_aux)133 brw_search_cache(struct brw_cache *cache,
134 enum brw_cache_id cache_id,
135 const void *key, GLuint key_size,
136 uint32_t *inout_offset, void *out_aux)
137 {
138 struct brw_context *brw = cache->brw;
139 struct brw_cache_item *item;
140 struct brw_cache_item lookup;
141 GLuint hash;
142
143 lookup.cache_id = cache_id;
144 lookup.key = key;
145 lookup.key_size = key_size;
146 hash = hash_key(&lookup);
147 lookup.hash = hash;
148
149 item = search_cache(cache, hash, &lookup);
150
151 if (item == NULL)
152 return false;
153
154 *(void **)out_aux = ((char *)item->key + item->key_size);
155
156 if (item->offset != *inout_offset) {
157 brw->state.dirty.cache |= (1 << cache_id);
158 *inout_offset = item->offset;
159 }
160
161 return true;
162 }
163
164 static void
brw_cache_new_bo(struct brw_cache * cache,uint32_t new_size)165 brw_cache_new_bo(struct brw_cache *cache, uint32_t new_size)
166 {
167 struct brw_context *brw = cache->brw;
168 struct intel_context *intel = &brw->intel;
169 drm_intel_bo *new_bo;
170
171 new_bo = drm_intel_bo_alloc(intel->bufmgr, "program cache", new_size, 64);
172
173 /* Copy any existing data that needs to be saved. */
174 if (cache->next_offset != 0) {
175 drm_intel_bo_map(cache->bo, false);
176 drm_intel_bo_subdata(new_bo, 0, cache->next_offset, cache->bo->virtual);
177 drm_intel_bo_unmap(cache->bo);
178 }
179
180 drm_intel_bo_unreference(cache->bo);
181 cache->bo = new_bo;
182 cache->bo_used_by_gpu = false;
183
184 /* Since we have a new BO in place, we need to signal the units
185 * that depend on it (state base address on gen5+, or unit state before).
186 */
187 brw->state.dirty.brw |= BRW_NEW_PROGRAM_CACHE;
188 }
189
190 /**
191 * Attempts to find an item in the cache with identical data and aux
192 * data to use
193 */
194 static bool
brw_try_upload_using_copy(struct brw_cache * cache,struct brw_cache_item * result_item,const void * data,const void * aux)195 brw_try_upload_using_copy(struct brw_cache *cache,
196 struct brw_cache_item *result_item,
197 const void *data,
198 const void *aux)
199 {
200 int i;
201 struct brw_cache_item *item;
202
203 for (i = 0; i < cache->size; i++) {
204 for (item = cache->items[i]; item; item = item->next) {
205 const void *item_aux = item->key + item->key_size;
206 int ret;
207
208 if (item->cache_id != result_item->cache_id ||
209 item->size != result_item->size ||
210 item->aux_size != result_item->aux_size) {
211 continue;
212 }
213
214 if (memcmp(item_aux, aux, item->aux_size) != 0) {
215 continue;
216 }
217
218 drm_intel_bo_map(cache->bo, false);
219 ret = memcmp(cache->bo->virtual + item->offset, data, item->size);
220 drm_intel_bo_unmap(cache->bo);
221 if (ret)
222 continue;
223
224 result_item->offset = item->offset;
225
226 return true;
227 }
228 }
229
230 return false;
231 }
232
233 static void
brw_upload_item_data(struct brw_cache * cache,struct brw_cache_item * item,const void * data)234 brw_upload_item_data(struct brw_cache *cache,
235 struct brw_cache_item *item,
236 const void *data)
237 {
238 /* Allocate space in the cache BO for our new program. */
239 if (cache->next_offset + item->size > cache->bo->size) {
240 uint32_t new_size = cache->bo->size * 2;
241
242 while (cache->next_offset + item->size > new_size)
243 new_size *= 2;
244
245 brw_cache_new_bo(cache, new_size);
246 }
247
248 /* If we would block on writing to an in-use program BO, just
249 * recreate it.
250 */
251 if (cache->bo_used_by_gpu) {
252 brw_cache_new_bo(cache, cache->bo->size);
253 }
254
255 item->offset = cache->next_offset;
256
257 /* Programs are always 64-byte aligned, so set up the next one now */
258 cache->next_offset = ALIGN(item->offset + item->size, 64);
259 }
260
261 void
brw_upload_cache(struct brw_cache * cache,enum brw_cache_id cache_id,const void * key,GLuint key_size,const void * data,GLuint data_size,const void * aux,GLuint aux_size,uint32_t * out_offset,void * out_aux)262 brw_upload_cache(struct brw_cache *cache,
263 enum brw_cache_id cache_id,
264 const void *key,
265 GLuint key_size,
266 const void *data,
267 GLuint data_size,
268 const void *aux,
269 GLuint aux_size,
270 uint32_t *out_offset,
271 void *out_aux)
272 {
273 struct brw_cache_item *item = CALLOC_STRUCT(brw_cache_item);
274 GLuint hash;
275 void *tmp;
276
277 item->cache_id = cache_id;
278 item->size = data_size;
279 item->key = key;
280 item->key_size = key_size;
281 item->aux_size = aux_size;
282 hash = hash_key(item);
283 item->hash = hash;
284
285 /* If we can find a matching prog/prog_data combo in the cache
286 * already, then reuse the existing stuff. This will mean not
287 * flagging CACHE_NEW_* when transitioning between the two
288 * equivalent hash keys. This is notably useful for programs
289 * generating shaders at runtime, where multiple shaders may
290 * compile to the thing in our backend.
291 */
292 if (!brw_try_upload_using_copy(cache, item, data, aux)) {
293 brw_upload_item_data(cache, item, data);
294 }
295
296 /* Set up the memory containing the key and aux_data */
297 tmp = malloc(key_size + aux_size);
298
299 memcpy(tmp, key, key_size);
300 memcpy(tmp + key_size, aux, aux_size);
301
302 item->key = tmp;
303
304 if (cache->n_items > cache->size * 1.5)
305 rehash(cache);
306
307 hash %= cache->size;
308 item->next = cache->items[hash];
309 cache->items[hash] = item;
310 cache->n_items++;
311
312 /* Copy data to the buffer */
313 drm_intel_bo_subdata(cache->bo, item->offset, data_size, data);
314
315 *out_offset = item->offset;
316 *(void **)out_aux = (void *)((char *)item->key + item->key_size);
317 cache->brw->state.dirty.cache |= 1 << cache_id;
318 }
319
320 void
brw_init_caches(struct brw_context * brw)321 brw_init_caches(struct brw_context *brw)
322 {
323 struct intel_context *intel = &brw->intel;
324 struct brw_cache *cache = &brw->cache;
325
326 cache->brw = brw;
327
328 cache->size = 7;
329 cache->n_items = 0;
330 cache->items = (struct brw_cache_item **)
331 calloc(1, cache->size * sizeof(struct brw_cache_item));
332
333 cache->bo = drm_intel_bo_alloc(intel->bufmgr,
334 "program cache",
335 4096, 64);
336 }
337
338 static void
brw_clear_cache(struct brw_context * brw,struct brw_cache * cache)339 brw_clear_cache(struct brw_context *brw, struct brw_cache *cache)
340 {
341 struct intel_context *intel = &brw->intel;
342 struct brw_cache_item *c, *next;
343 GLuint i;
344
345 DBG("%s\n", __FUNCTION__);
346
347 for (i = 0; i < cache->size; i++) {
348 for (c = cache->items[i]; c; c = next) {
349 next = c->next;
350 free((void *)c->key);
351 free(c);
352 }
353 cache->items[i] = NULL;
354 }
355
356 cache->n_items = 0;
357
358 /* Start putting programs into the start of the BO again, since
359 * we'll never find the old results.
360 */
361 cache->next_offset = 0;
362
363 /* We need to make sure that the programs get regenerated, since
364 * any offsets leftover in brw_context will no longer be valid.
365 */
366 brw->state.dirty.mesa |= ~0;
367 brw->state.dirty.brw |= ~0;
368 brw->state.dirty.cache |= ~0;
369 intel_batchbuffer_flush(intel);
370 }
371
372 void
brw_state_cache_check_size(struct brw_context * brw)373 brw_state_cache_check_size(struct brw_context *brw)
374 {
375 /* un-tuned guess. Each object is generally a page, so 2000 of them is 8 MB of
376 * state cache.
377 */
378 if (brw->cache.n_items > 2000) {
379 perf_debug("Exceeded state cache size limit. Clearing the set "
380 "of compiled programs, which will trigger recompiles\n");
381 brw_clear_cache(brw, &brw->cache);
382 }
383 }
384
385
386 static void
brw_destroy_cache(struct brw_context * brw,struct brw_cache * cache)387 brw_destroy_cache(struct brw_context *brw, struct brw_cache *cache)
388 {
389
390 DBG("%s\n", __FUNCTION__);
391
392 drm_intel_bo_unreference(cache->bo);
393 cache->bo = NULL;
394 brw_clear_cache(brw, cache);
395 free(cache->items);
396 cache->items = NULL;
397 cache->size = 0;
398 }
399
400
401 void
brw_destroy_caches(struct brw_context * brw)402 brw_destroy_caches(struct brw_context *brw)
403 {
404 brw_destroy_cache(brw, &brw->cache);
405 }
406