gc part of the block at a time to reduce latency

[yaffs2.git] / yaffs_guts.c

diff --git a/yaffs_guts.c b/yaffs_guts.c
index 5c1cfdc6cf240c99c59092c3698faa42bd38245a..34e94a0a93942b2b931026beef9fa8e31624bc53 100644 (file)
--- a/yaffs_guts.c
+++ b/yaffs_guts.c
@@ -12,7 +12,7 @@
  */
 
 const char *yaffs_guts_c_version =
-    "$Id: yaffs_guts.c,v 1.66 2008-11-26 20:46:47 charles Exp $";
+    "$Id: yaffs_guts.c,v 1.67 2008-11-27 02:46:45 charles Exp $";
 
 #include "yportenv.h"
 
@@ -2993,17 +2993,17 @@ static int yaffs_GetErasedChunks(yaffs_Device * dev)
 
 }
 
-static int yaffs_GarbageCollectBlock(yaffs_Device * dev, int block)
+static int yaffs_GarbageCollectBlock(yaffs_Device * dev, int block, int wholeBlock)
 {
        int oldChunk;
        int newChunk;
-       int chunkInBlock;
        int markNAND;
        int retVal = YAFFS_OK;
        int cleanups = 0;
        int i;
        int isCheckpointBlock;
        int matchingChunk;
+       int maxCopies;
 
        int chunksBefore = yaffs_GetErasedChunks(dev);
        int chunksAfter;
@@ -3019,8 +3019,11 @@ static int yaffs_GarbageCollectBlock(yaffs_Device * dev, int block)
        bi->blockState = YAFFS_BLOCK_STATE_COLLECTING;
 
        T(YAFFS_TRACE_TRACING,
-         (TSTR("Collecting block %d, in use %d, shrink %d, " TENDSTR), block,
-          bi->pagesInUse, bi->hasShrinkHeader));
+         (TSTR("Collecting block %d, in use %d, shrink %d, wholeBlock %d" TENDSTR), 
+         block,
+         bi->pagesInUse,
+         bi->hasShrinkHeader,
+         wholeBlock));
 
        /*yaffs_VerifyFreeChunks(dev); */
 
@@ -3046,14 +3049,20 @@ static int yaffs_GarbageCollectBlock(yaffs_Device * dev, int block)
                
                yaffs_VerifyBlock(dev,bi,block);
 
-               for (chunkInBlock = 0, oldChunk = block * dev->nChunksPerBlock;
+               maxCopies = (wholeBlock) ? dev->nChunksPerBlock : 10;
+               oldChunk = block * dev->nChunksPerBlock + dev->gcChunk;
+               
+               for ( /* init already done */;
                     retVal == YAFFS_OK &&
-                    chunkInBlock < dev->nChunksPerBlock
-                    && yaffs_StillSomeChunkBits(dev, block);
-                    chunkInBlock++, oldChunk++) {
-                       if (yaffs_CheckChunkBit(dev, block, chunkInBlock)) {
+                    dev->gcChunk < dev->nChunksPerBlock &&
+                    (bi->blockState == YAFFS_BLOCK_STATE_COLLECTING)&&
+                    maxCopies > 0;
+                    dev->gcChunk++, oldChunk++) {
+                       if (yaffs_CheckChunkBit(dev, block, dev->gcChunk)) {
 
                                /* This page is in use and might need to be copied off */
+                               
+                               maxCopies--;
 
                                markNAND = 1;
 
@@ -3068,8 +3077,8 @@ static int yaffs_GarbageCollectBlock(yaffs_Device * dev, int block)
 
                                T(YAFFS_TRACE_GC_DETAIL,
                                  (TSTR
-                                  ("Collecting page %d, %d %d %d " TENDSTR),
-                                  chunkInBlock, tags.objectId, tags.chunkId,
+                                  ("Collecting chunk in block %d, %d %d %d " TENDSTR),
+                                  dev->gcChunk, tags.objectId, tags.chunkId,
                                   tags.byteCount));
                                   
                                if(object && !yaffs_SkipVerification(dev)){
@@ -3184,6 +3193,7 @@ static int yaffs_GarbageCollectBlock(yaffs_Device * dev, int block)
                }
 
                yaffs_ReleaseTempBuffer(dev, buffer, __LINE__);
+               
 
 
                /* Do any required cleanups */
@@ -3218,6 +3228,12 @@ static int yaffs_GarbageCollectBlock(yaffs_Device * dev, int block)
                    TENDSTR), chunksBefore, chunksAfter));
        }
 
+       /* If the gc completed then clear the current gcBlock so that we find another. */
+       if(bi->blockState != YAFFS_BLOCK_STATE_COLLECTING){
+               dev->gcBlock = -1;
+               dev->gcChunk = 0;
+       }
+       
        dev->isDoingGC = 0;
 
        return retVal;
@@ -3265,7 +3281,12 @@ static int yaffs_CheckGarbageCollection(yaffs_Device * dev)
                        aggressive = 0;
                }
 
-               block = yaffs_FindBlockForGarbageCollection(dev, aggressive);
+               if(dev->gcBlock <= 0){
+                       dev->gcBlock = yaffs_FindBlockForGarbageCollection(dev, aggressive);
+                       dev->gcChunk = 0;
+               }
+               
+               block = dev->gcBlock;
 
                if (block > 0) {
                        dev->garbageCollections++;
@@ -3278,7 +3299,7 @@ static int yaffs_CheckGarbageCollection(yaffs_Device * dev)
                           ("yaffs: GC erasedBlocks %d aggressive %d" TENDSTR),
                           dev->nErasedBlocks, aggressive));
 
-                       gcOk = yaffs_GarbageCollectBlock(dev, block);
+                       gcOk = yaffs_GarbageCollectBlock(dev,block,aggressive);
                }
 
                if (dev->nErasedBlocks < (dev->nReservedBlocks) && block > 0) {
@@ -3287,8 +3308,9 @@ static int yaffs_CheckGarbageCollection(yaffs_Device * dev)
                           ("yaffs: GC !!!no reclaim!!! erasedBlocks %d after try %d block %d"
                            TENDSTR), dev->nErasedBlocks, maxTries, block));
                }
-       } while ((dev->nErasedBlocks < dev->nReservedBlocks) && (block > 0)
-                && (maxTries < 2));
+       } while ((dev->nErasedBlocks < dev->nReservedBlocks) && 
+                (block > 0) &&
+                (maxTries < 2));
 
        return aggressive ? gcOk : YAFFS_OK;
 }
@@ -7221,6 +7243,8 @@ int yaffs_GutsInitialise(yaffs_Device * dev)
        dev->blockOffset = 0;
        dev->chunkOffset = 0;
        dev->nFreeChunks = 0;
+       
+       dev->gcBlock = -1;
 
        if (dev->startBlock == 0) {
                dev->internalStartBlock = dev->startBlock + 1;