1 files changed, 442 insertions, 0 deletions

diff --git a/source/blender/imbuf/intern/cache.c b/source/blender/imbuf/intern/cache.c
new file mode 100644
index 00000000000..d15826df2f0
--- /dev/null
+++ b/source/blender/imbuf/intern/cache.c
@@ -0,0 +1,442 @@
+/*
+ * $Id$
+ *
+ * ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+#include "BLI_ghash.h"
+#include "BLI_listbase.h"
+#include "BLI_memarena.h"
+#include "BLI_threads.h"
+
+#include "BKE_utildefines.h"
+
+#include "IMB_imbuf.h"
+#include "IMB_imbuf_types.h"
+#include "IMB_filetype.h"
+
+#include "imbuf.h"
+
+/* We use a two level cache here. A per-thread cache with limited number of
+   tiles. This can be accessed without locking and so is hoped to lead to most
+   tile access being lock-free. The global cache is shared between all threads
+   and requires slow locking to access, and contains all tiles.
+   
+   The per-thread cache should be big enough that one might hope to not fall
+   back to the global cache every pixel, but not to big to keep too many tiles
+   locked and using memory. */
+
+#define IB_THREAD_CACHE_SIZE	100
+
+typedef struct ImGlobalTile {
+	struct ImGlobalTile *next, *prev;
+
+	ImBuf *ibuf;
+	int tx, ty;
+	int refcount;
+	volatile int loading;
+} ImGlobalTile;
+
+typedef struct ImThreadTile {
+	struct ImThreadTile *next, *prev;
+
+	ImBuf *ibuf;
+	int tx, ty;
+
+	ImGlobalTile *global;
+} ImThreadTile;
+
+typedef struct ImThreadTileCache {
+	ListBase tiles;
+	ListBase unused;
+	GHash *tilehash;
+} ImThreadTileCache;
+
+typedef struct ImGlobalTileCache {
+	ListBase tiles;
+	ListBase unused;
+	GHash *tilehash;
+
+	MemArena *memarena;
+	uintptr_t totmem, maxmem;
+
+	ImThreadTileCache thread_cache[BLENDER_MAX_THREADS+1];
+	int totthread;
+
+	ThreadMutex mutex;
+} ImGlobalTileCache;
+
+static ImGlobalTileCache GLOBAL_CACHE;
+
+/***************************** Hash Functions ********************************/
+
+static unsigned int imb_global_tile_hash(void *gtile_p)
+{
+	ImGlobalTile *gtile= gtile_p;
+
+	return ((unsigned int)(intptr_t)gtile->ibuf)*769 + gtile->tx*53 + gtile->ty*97;
+}
+
+static int imb_global_tile_cmp(void *a_p, void *b_p)
+{
+	ImGlobalTile *a= a_p;
+	ImGlobalTile *b= b_p;
+
+	if(a->ibuf == b->ibuf && a->tx == b->tx && a->ty == b->ty) return 0;
+	else if(a->ibuf < b->ibuf || a->tx < b->tx || a->ty < b->ty) return -1;
+	else return 1;
+}
+
+static unsigned int imb_thread_tile_hash(void *ttile_p)
+{
+	ImThreadTile *ttile= ttile_p;
+
+	return ((unsigned int)(intptr_t)ttile->ibuf)*769 + ttile->tx*53 + ttile->ty*97;
+}
+
+static int imb_thread_tile_cmp(void *a_p, void *b_p)
+{
+	ImThreadTile *a= a_p;
+	ImThreadTile *b= b_p;
+
+	if(a->ibuf == b->ibuf && a->tx == b->tx && a->ty == b->ty) return 0;
+	else if(a->ibuf < b->ibuf || a->tx < b->tx || a->ty < b->ty) return -1;
+	else return 1;
+}
+
+/******************************** Load/Unload ********************************/
+
+static void imb_global_cache_tile_load(ImGlobalTile *gtile)
+{
+	ImBuf *ibuf= gtile->ibuf;
+	int toffs= ibuf->xtiles*gtile->ty + gtile->tx;
+	unsigned int *rect;
+
+	rect = MEM_callocN(sizeof(unsigned int)*ibuf->tilex*ibuf->tiley, "imb_tile");
+	imb_loadtile(ibuf, gtile->tx, gtile->ty, rect);
+	ibuf->tiles[toffs]= rect;
+}
+
+static void imb_global_cache_tile_unload(ImGlobalTile *gtile)
+{
+	ImBuf *ibuf= gtile->ibuf;
+	int toffs= ibuf->xtiles*gtile->ty + gtile->tx;
+
+	MEM_freeN(ibuf->tiles[toffs]);
+	ibuf->tiles[toffs]= NULL;
+
+	GLOBAL_CACHE.totmem -= sizeof(unsigned int)*ibuf->tilex*ibuf->tiley;
+}
+
+/* external free */
+void imb_tile_cache_tile_free(ImBuf *ibuf, int tx, int ty)
+{
+	ImGlobalTile *gtile, lookuptile;
+
+	BLI_mutex_lock(&GLOBAL_CACHE.mutex);
+
+	lookuptile.ibuf = ibuf;
+	lookuptile.tx = tx;
+	lookuptile.ty = ty;
+	gtile= BLI_ghash_lookup(GLOBAL_CACHE.tilehash, &lookuptile);
+
+	if(gtile) {
+		/* in case another thread is loading this */
+		while(gtile->loading)
+			;
+
+		BLI_ghash_remove(GLOBAL_CACHE.tilehash, gtile, NULL, NULL);
+		BLI_remlink(&GLOBAL_CACHE.tiles, gtile);
+		BLI_addtail(&GLOBAL_CACHE.unused, gtile);
+	}
+
+	BLI_mutex_unlock(&GLOBAL_CACHE.mutex);
+}
+
+/******************************* Init/Exit ***********************************/
+
+static void imb_thread_cache_init(ImThreadTileCache *cache)
+{
+	ImThreadTile *ttile;
+	int a;
+
+	memset(cache, 0, sizeof(ImThreadTileCache));
+
+	cache->tilehash= BLI_ghash_new(imb_thread_tile_hash, imb_thread_tile_cmp, "imb_thread_cache_init gh");
+
+	/* pre-allocate all thread local tiles in unused list */
+	for(a=0; a<IB_THREAD_CACHE_SIZE; a++) {
+		ttile= BLI_memarena_alloc(GLOBAL_CACHE.memarena, sizeof(ImThreadTile));
+		BLI_addtail(&cache->unused, ttile);
+	}
+}
+
+static void imb_thread_cache_exit(ImThreadTileCache *cache)
+{
+	BLI_ghash_free(cache->tilehash, NULL, NULL);
+}
+
+void imb_tile_cache_init(void)
+{
+	memset(&GLOBAL_CACHE, 0, sizeof(ImGlobalTileCache));
+
+	BLI_mutex_init(&GLOBAL_CACHE.mutex);
+
+	/* initialize for one thread, for places that access textures
+	   outside of rendering (displace modifier, painting, ..) */
+	IMB_tile_cache_params(0, 0);
+}
+
+void imb_tile_cache_exit(void)
+{
+	ImGlobalTile *gtile;
+	int a;
+
+	for(gtile=GLOBAL_CACHE.tiles.first; gtile; gtile=gtile->next)
+		imb_global_cache_tile_unload(gtile);
+
+	for(a=0; a<GLOBAL_CACHE.totthread; a++)
+		imb_thread_cache_exit(&GLOBAL_CACHE.thread_cache[a]);
+
+	if(GLOBAL_CACHE.memarena)
+		BLI_memarena_free(GLOBAL_CACHE.memarena);
+
+	if(GLOBAL_CACHE.tilehash)
+		BLI_ghash_free(GLOBAL_CACHE.tilehash, NULL, NULL);
+
+	BLI_mutex_end(&GLOBAL_CACHE.mutex);
+}
+
+/* presumed to be called when no threads are running */
+void IMB_tile_cache_params(int totthread, int maxmem)
+{
+	int a;
+
+	/* always one cache for non-threaded access */
+	totthread++;
+
+	/* lazy initialize cache */
+	if(GLOBAL_CACHE.totthread == totthread && GLOBAL_CACHE.maxmem == maxmem)
+		return;
+
+	imb_tile_cache_exit();
+
+	memset(&GLOBAL_CACHE, 0, sizeof(ImGlobalTileCache));
+
+	GLOBAL_CACHE.tilehash= BLI_ghash_new(imb_global_tile_hash, imb_global_tile_cmp, "tile_cache_params gh");
+
+	GLOBAL_CACHE.memarena= BLI_memarena_new(BLI_MEMARENA_STD_BUFSIZE, "ImTileCache arena");
+	BLI_memarena_use_calloc(GLOBAL_CACHE.memarena);
+
+	GLOBAL_CACHE.maxmem= maxmem*1024*1024;
+
+	GLOBAL_CACHE.totthread= totthread;
+	for(a=0; a<totthread; a++)
+		imb_thread_cache_init(&GLOBAL_CACHE.thread_cache[a]);
+
+	BLI_mutex_init(&GLOBAL_CACHE.mutex);
+}
+
+/***************************** Global Cache **********************************/
+
+static ImGlobalTile *imb_global_cache_get_tile(ImBuf *ibuf, int tx, int ty, ImGlobalTile *replacetile)
+{
+	ImGlobalTile *gtile, lookuptile;
+
+	BLI_mutex_lock(&GLOBAL_CACHE.mutex);
+
+	if(replacetile)
+		replacetile->refcount--;
+
+	/* find tile in global cache */
+	lookuptile.ibuf = ibuf;
+	lookuptile.tx = tx;
+	lookuptile.ty = ty;
+	gtile= BLI_ghash_lookup(GLOBAL_CACHE.tilehash, &lookuptile);
+	
+	if(gtile) {
+		/* found tile. however it may be in the process of being loaded
+		   by another thread, in that case we do stupid busy loop waiting
+		   for the other thread to load the tile */
+		gtile->refcount++;
+
+		BLI_mutex_unlock(&GLOBAL_CACHE.mutex);
+
+		while(gtile->loading)
+			;
+	}
+	else {
+		/* not found, let's load it from disk */
+
+		/* first check if we hit the memory limit */
+		if(GLOBAL_CACHE.maxmem && GLOBAL_CACHE.totmem > GLOBAL_CACHE.maxmem) {
+			/* find an existing tile to unload */
+			for(gtile=GLOBAL_CACHE.tiles.last; gtile; gtile=gtile->prev)
+				if(gtile->refcount == 0 && gtile->loading == 0)
+					break;
+		}
+
+		if(gtile) {
+			/* found a tile to unload */
+			imb_global_cache_tile_unload(gtile);
+			BLI_ghash_remove(GLOBAL_CACHE.tilehash, gtile, NULL, NULL);
+			BLI_remlink(&GLOBAL_CACHE.tiles, gtile);
+		}
+		else {
+			/* allocate a new tile or reuse unused */
+			if(GLOBAL_CACHE.unused.first) {
+				gtile= GLOBAL_CACHE.unused.first;
+				BLI_remlink(&GLOBAL_CACHE.unused, gtile);
+			}
+			else
+				gtile= BLI_memarena_alloc(GLOBAL_CACHE.memarena, sizeof(ImGlobalTile));
+		}
+
+		/* setup new tile */
+		gtile->ibuf= ibuf;
+		gtile->tx= tx;
+		gtile->ty= ty;
+		gtile->refcount= 1;
+		gtile->loading= 1;
+
+		BLI_ghash_insert(GLOBAL_CACHE.tilehash, gtile, gtile);
+		BLI_addhead(&GLOBAL_CACHE.tiles, gtile);
+
+		/* mark as being loaded and unlock to allow other threads to load too */
+		GLOBAL_CACHE.totmem += sizeof(unsigned int)*ibuf->tilex*ibuf->tiley;
+
+		BLI_mutex_unlock(&GLOBAL_CACHE.mutex);
+
+		/* load from disk */
+		imb_global_cache_tile_load(gtile);
+
+		/* mark as done loading */
+		gtile->loading= 0;
+	}
+
+	return gtile;
+}
+
+/***************************** Per-Thread Cache ******************************/
+
+static unsigned int *imb_thread_cache_get_tile(ImThreadTileCache *cache, ImBuf *ibuf, int tx, int ty)
+{
+	ImThreadTile *ttile, lookuptile;
+	ImGlobalTile *gtile, *replacetile;
+	int toffs= ibuf->xtiles*ty + tx;
+
+	/* test if it is already in our thread local cache */
+	if((ttile=cache->tiles.first)) {
+		/* check last used tile before going to hash */
+		if(ttile->ibuf == ibuf && ttile->tx == tx && ttile->ty == ty)
+			return ibuf->tiles[toffs];
+
+		/* find tile in hash */
+		lookuptile.ibuf = ibuf;
+		lookuptile.tx = tx;
+		lookuptile.ty = ty;
+
+		if((ttile=BLI_ghash_lookup(cache->tilehash, &lookuptile))) {
+			BLI_remlink(&cache->tiles, ttile);
+			BLI_addhead(&cache->tiles, ttile);
+
+			return ibuf->tiles[toffs];
+		}
+	}
+
+	/* not found, have to do slow lookup in global cache */
+	if(cache->unused.first == NULL) {
+		ttile= cache->tiles.last;
+		replacetile= ttile->global;
+		BLI_remlink(&cache->tiles, ttile);
+		BLI_ghash_remove(cache->tilehash, ttile, NULL, NULL);
+	}
+	else {
+		ttile= cache->unused.first;
+		replacetile= NULL;
+		BLI_remlink(&cache->unused, ttile);
+	}
+
+	BLI_addhead(&cache->tiles, ttile);
+	BLI_ghash_insert(cache->tilehash, ttile, ttile);
+
+	gtile= imb_global_cache_get_tile(ibuf, tx, ty, replacetile);
+
+	ttile->ibuf= gtile->ibuf;
+	ttile->tx= gtile->tx;
+	ttile->ty= gtile->ty;
+	ttile->global= gtile;
+
+	return ibuf->tiles[toffs];
+}
+
+unsigned int *IMB_gettile(ImBuf *ibuf, int tx, int ty, int thread)
+{
+	return imb_thread_cache_get_tile(&GLOBAL_CACHE.thread_cache[thread+1], ibuf, tx, ty);
+}
+
+void IMB_tiles_to_rect(ImBuf *ibuf)
+{
+	ImBuf *mipbuf;
+	ImGlobalTile *gtile;
+	unsigned int *to, *from;
+	int a, tx, ty, y, w, h;
+
+	for(a=0; a<ibuf->miptot; a++) {
+		mipbuf= IMB_getmipmap(ibuf, a);
+
+		/* don't call imb_addrectImBuf, it frees all mipmaps */
+		if(!mipbuf->rect) {
+			if((mipbuf->rect = MEM_mapallocN(ibuf->x*ibuf->y*sizeof(unsigned int), "imb_addrectImBuf"))) {
+				mipbuf->mall |= IB_rect;
+				mipbuf->flags |= IB_rect;
+			}
+			else
+				break;
+		}
+
+		for(ty=0; ty<mipbuf->ytiles; ty++) {
+			for(tx=0; tx<mipbuf->xtiles; tx++) {
+				/* acquire tile through cache, this assumes cache is initialized,
+				   which it is always now but it's a weak assumption ... */
+				gtile= imb_global_cache_get_tile(mipbuf, tx, ty, NULL);
+
+				/* setup pointers */
+				from= mipbuf->tiles[mipbuf->xtiles*ty + tx];
+				to= mipbuf->rect + mipbuf->x*ty*mipbuf->tiley + tx*mipbuf->tilex;
+
+				/* exception in tile width/height for tiles at end of image */
+				w= (tx == mipbuf->xtiles-1)? mipbuf->x - tx*mipbuf->tilex: mipbuf->tilex;
+				h= (ty == mipbuf->ytiles-1)? mipbuf->y - ty*mipbuf->tiley: mipbuf->tiley;
+
+				for(y=0; y<h; y++) {
+					memcpy(to, from, sizeof(unsigned int)*w);
+					from += mipbuf->tilex;
+					to += mipbuf->x;
+				}
+
+				/* decrease refcount for tile again */
+				BLI_mutex_lock(&GLOBAL_CACHE.mutex);
+				gtile->refcount--;
+				BLI_mutex_unlock(&GLOBAL_CACHE.mutex);
+			}
+		}
+	}
+}
+