#include "yaffs_packedtags2.h"
-#define YAFFS_PASSIVE_GC_CHUNKS 2
+/* Note YAFFS_GC_GOOD_ENOUGH must be <= YAFFS_GC_PASSIVE_THRESHOLD */
+#define YAFFS_GC_GOOD_ENOUGH 2
+#define YAFFS_GC_PASSIVE_THRESHOLD 4
#define YAFFS_SMALL_HOLE_THRESHOLD 3
#include "yaffs_ecc.h"
* yaffs_FindOldestDirtySequence()
* Calculate the oldest dirty sequence number if we don't know it.
*/
-static int yaffs_CalcOldestDirtySequence(yaffs_Device *dev)
+static void yaffs_CalcOldestDirtySequence(yaffs_Device *dev)
{
int i;
- __u32 seq;
+ unsigned seq;
+ unsigned blockNo = 0;
yaffs_BlockInfo *b;
if(!dev->param.isYaffs2)
- return 0;
+ return;
/* Find the oldest dirty sequence number. */
- seq = dev->sequenceNumber;
+ seq = dev->sequenceNumber + 1;
b = dev->blockInfo;
for (i = dev->internalStartBlock; i <= dev->internalEndBlock; i++) {
if (b->blockState == YAFFS_BLOCK_STATE_FULL &&
- (b->pagesInUse - b->softDeletions) < dev->param.nChunksPerBlock &&
- b->sequenceNumber < seq)
- seq = b->sequenceNumber;
+ (b->pagesInUse - b->softDeletions) < dev->param.nChunksPerBlock &&
+ b->sequenceNumber < seq) {
+ seq = b->sequenceNumber;
+ blockNo = i;
+ }
b++;
}
- return seq;
+
+ if(blockNo){
+ dev->oldestDirtySequence = seq;
+ dev->oldestDirtyBlock = blockNo;
+ }
+
}
static void yaffs_FindOldestDirtySequence(yaffs_Device *dev)
{
if(dev->param.isYaffs2 && !dev->oldestDirtySequence)
- dev->oldestDirtySequence =
- yaffs_CalcOldestDirtySequence(dev);
-
-#if 0
- if(!yaffs_SkipVerification(dev) &&
- dev->oldestDirtySequence != yaffs_CalcOldestDirtySequence(dev))
- YBUG();
-
-#endif
+ yaffs_CalcOldestDirtySequence(dev);
}
/*
if(!dev->param.isYaffs2)
return;
- if(!bi || bi->sequenceNumber == dev->oldestDirtySequence)
+ if(!bi || bi->sequenceNumber == dev->oldestDirtySequence){
dev->oldestDirtySequence = 0;
+ dev->oldestDirtyBlock = 0;
+ }
}
/*
* Update the oldest dirty sequence number whenever we dirty a block.
* Only do this if the oldestDirtySequence is actually being tracked.
*/
-static void yaffs_UpdateOldestDirtySequence(yaffs_Device *dev, yaffs_BlockInfo *bi)
+static void yaffs_UpdateOldestDirtySequence(yaffs_Device *dev, unsigned blockNo, yaffs_BlockInfo *bi)
{
if(dev->param.isYaffs2 && dev->oldestDirtySequence){
- if(dev->oldestDirtySequence > bi->sequenceNumber)
+ if(dev->oldestDirtySequence > bi->sequenceNumber){
dev->oldestDirtySequence = bi->sequenceNumber;
+ dev->oldestDirtyBlock = blockNo;
+ }
}
}
static void yaffs_SoftDeleteChunk(yaffs_Device *dev, int chunk)
{
yaffs_BlockInfo *theBlock;
+ unsigned blockNo;
T(YAFFS_TRACE_DELETION, (TSTR("soft delete chunk %d" TENDSTR), chunk));
- theBlock = yaffs_GetBlockInfo(dev, chunk / dev->param.nChunksPerBlock);
+ blockNo = chunk / dev->param.nChunksPerBlock;
+ theBlock = yaffs_GetBlockInfo(dev, blockNo);
if (theBlock) {
theBlock->softDeletions++;
dev->nFreeChunks++;
- yaffs_UpdateOldestDirtySequence(dev,theBlock);
+ yaffs_UpdateOldestDirtySequence(dev, blockNo, theBlock);
}
}
* Note we must disable gc otherwise it can mess up the shadowing.
*
*/
- dev->isDoingGC=1;
+ dev->gcDisable=1;
yaffs_ChangeObjectName(obj, newDir, newName, force,
existingTarget->objectId);
existingTarget->isShadowed = 1;
yaffs_UnlinkObject(existingTarget);
- dev->isDoingGC=0;
+ dev->gcDisable=0;
}
result = yaffs_ChangeObjectName(obj, newDir, newName, 1, 0);
if(dev->refreshSkip > dev->param.refreshPeriod)
dev->refreshSkip = dev->param.refreshPeriod;
- if(dev->refreshSkip > 0){
- dev->refreshSkip--;
+ if(dev->refreshSkip > 0)
return oldest;
- }
/*
* Refresh skip is now zero.
return oldest;
}
-/*
- * FindDiretiestBlock is used to select the dirtiest block (or close enough)
- * for garbage collection.
- */
-
-static int yaffs_FindBlockForGarbageCollection(yaffs_Device *dev,
- int aggressive)
-{
- int b = dev->currentDirtyChecker;
-
- int i;
- int iterations;
- int dirtiest = -1;
- int pagesInUse = 0;
- int prioritised = 0;
- yaffs_BlockInfo *bi;
- int pendingPrioritisedExist = 0;
-
- /* First let's see if we need to grab a prioritised block */
- if (dev->hasPendingPrioritisedGCs) {
- bi = dev->blockInfo;
- for (i = dev->internalStartBlock; i < dev->internalEndBlock && !prioritised; i++) {
-
- if (bi->gcPrioritise) {
- pendingPrioritisedExist = 1;
- if (bi->blockState == YAFFS_BLOCK_STATE_FULL &&
- yaffs_BlockNotDisqualifiedFromGC(dev, bi)) {
- pagesInUse = (bi->pagesInUse - bi->softDeletions);
- dirtiest = i;
- prioritised = 1;
- aggressive = 1; /* Fool the non-aggressive skip logiv below */
- }
- }
- bi++;
- }
-
- if (!pendingPrioritisedExist) /* None found, so we can clear this */
- dev->hasPendingPrioritisedGCs = 0;
- }
-
- /* If we're doing aggressive GC then we are happy to take a less-dirty block, and
- * search harder.
- * else (we're doing a leasurely gc), then we only bother to do this if the
- * block has only a few pages in use.
- */
-
- dev->nonAggressiveSkip--;
-
- if (!aggressive && (dev->nonAggressiveSkip > 0))
- return -1;
-
- if (!prioritised)
- pagesInUse =
- (aggressive) ? dev->param.nChunksPerBlock : YAFFS_PASSIVE_GC_CHUNKS + 1;
-
- if (aggressive)
- iterations =
- dev->internalEndBlock - dev->internalStartBlock + 1;
- else {
- iterations =
- dev->internalEndBlock - dev->internalStartBlock + 1;
- iterations = iterations / 16;
- if (iterations > 200)
- iterations = 200;
- }
-
- for (i = 0; i <= iterations && pagesInUse > 0 && !prioritised; i++) {
- b++;
- if (b < dev->internalStartBlock || b > dev->internalEndBlock)
- b = dev->internalStartBlock;
-
- if (b < dev->internalStartBlock || b > dev->internalEndBlock) {
- T(YAFFS_TRACE_ERROR,
- (TSTR("**>> Block %d is not valid" TENDSTR), b));
- YBUG();
- }
-
- bi = yaffs_GetBlockInfo(dev, b);
-
- if (bi->blockState == YAFFS_BLOCK_STATE_FULL &&
- (bi->pagesInUse - bi->softDeletions) < pagesInUse &&
- yaffs_BlockNotDisqualifiedFromGC(dev, bi)) {
- dirtiest = b;
- pagesInUse = (bi->pagesInUse - bi->softDeletions);
- }
- }
-
- dev->currentDirtyChecker = b;
-
- if (dirtiest > 0) {
- T(YAFFS_TRACE_GC,
- (TSTR("GC Selected block %d with %d free, prioritised:%d" TENDSTR), dirtiest,
- dev->param.nChunksPerBlock - pagesInUse, prioritised));
- }
-
- if (dirtiest > 0)
- dev->nonAggressiveSkip = 4;
-
- return dirtiest;
-}
static void yaffs_BlockBecameDirty(yaffs_Device *dev, int blockNo)
{
/* If this is the block being garbage collected then stop gc'ing this block */
if(blockNo == dev->gcBlock)
- dev->gcBlock = -1;
+ dev->gcBlock = 0;
+
+ /* If this block is currently the best candidate for gc then drop as a candidate */
+ if(blockNo == dev->gcDirtiest){
+ dev->gcDirtiest = 0;
+ dev->gcPagesInUse = 0;
+ }
if (!bi->needsRetiring) {
yaffs_InvalidateCheckpoint(dev);
bi->hasShrinkHeader = 0; /* clear the flag so that the block can erase */
- dev->isDoingGC = 1;
+ dev->gcDisable = 1;
if (isCheckpointBlock ||
!yaffs_StillSomeChunkBits(dev, block)) {
yaffs_VerifyBlock(dev, bi, block);
- maxCopies = (wholeBlock) ? dev->param.nChunksPerBlock : 10;
+ maxCopies = (wholeBlock) ? dev->param.nChunksPerBlock : 5;
oldChunk = block * dev->param.nChunksPerBlock + dev->gcChunk;
for (/* init already done */;
("gc did not increase free chunks before %d after %d"
TENDSTR), chunksBefore, chunksAfter));
}
- dev->gcBlock = -1;
+ dev->gcBlock = 0;
dev->gcChunk = 0;
}
- dev->isDoingGC = 0;
+ dev->gcDisable = 0;
return retVal;
}
+/*
+ * FindBlockForgarbageCollection is used to select the dirtiest block (or close enough)
+ * for garbage collection.
+ */
+
+static unsigned yaffs_FindBlockForGarbageCollection(yaffs_Device *dev,
+ int aggressive,
+ int background)
+{
+ int i;
+ int iterations;
+ unsigned selected = 0;
+ int prioritised = 0;
+ int prioritisedExists = 0;
+ yaffs_BlockInfo *bi;
+ int threshold;
+
+ /* First let's see if we need to grab a prioritised block */
+ if (dev->hasPendingPrioritisedGCs && !aggressive) {
+ dev->gcDirtiest = 0;
+ bi = dev->blockInfo;
+ for (i = dev->internalStartBlock;
+ i <= dev->internalEndBlock && !selected;
+ i++) {
+
+ if (bi->gcPrioritise) {
+ prioritisedExists = 1;
+ if (bi->blockState == YAFFS_BLOCK_STATE_FULL &&
+ yaffs_BlockNotDisqualifiedFromGC(dev, bi)) {
+ selected = i;
+ prioritised = 1;
+ }
+ }
+ bi++;
+ }
+
+ /*
+ * If there is a prioritised block and none was selected then
+ * this happened because there is at least one old dirty block gumming
+ * up the works. Let's gc the oldest dirty block.
+ */
+
+ if(prioritisedExists &&
+ !selected &&
+ dev->oldestDirtyBlock > 0)
+ selected = dev->oldestDirtyBlock;
+
+ if (!prioritisedExists) /* None found, so we can clear this */
+ dev->hasPendingPrioritisedGCs = 0;
+ }
+
+ /* If we're doing aggressive GC then we are happy to take a less-dirty block, and
+ * search harder.
+ * else (we're doing a leasurely gc), then we only bother to do this if the
+ * block has only a few pages in use.
+ */
+
+ if (!selected){
+ int pagesUsed;
+ int nBlocks = dev->internalEndBlock - dev->internalStartBlock + 1;
+ if (aggressive){
+ threshold = dev->param.nChunksPerBlock;
+ iterations = nBlocks;
+ } else {
+ int maxThreshold = dev->param.nChunksPerBlock/2;
+ threshold = background ?
+ (dev->gcNotDone + 2) * 2 : 0;
+ if(threshold <YAFFS_GC_PASSIVE_THRESHOLD)
+ threshold = YAFFS_GC_PASSIVE_THRESHOLD;
+ if(threshold > maxThreshold)
+ threshold = maxThreshold;
+
+ iterations = nBlocks / 16 + 1;
+ if (iterations > 100)
+ iterations = 100;
+ }
+
+ for (i = 0;
+ i < iterations &&
+ (dev->gcDirtiest < 1 ||
+ dev->gcPagesInUse > YAFFS_GC_GOOD_ENOUGH);
+ i++) {
+ dev->gcBlockFinder++;
+ if (dev->gcBlockFinder < dev->internalStartBlock ||
+ dev->gcBlockFinder > dev->internalEndBlock)
+ dev->gcBlockFinder = dev->internalStartBlock;
+
+ bi = yaffs_GetBlockInfo(dev, dev->gcBlockFinder);
+
+ pagesUsed = bi->pagesInUse - bi->softDeletions;
+
+ if (bi->blockState == YAFFS_BLOCK_STATE_FULL &&
+ pagesUsed < dev->param.nChunksPerBlock &&
+ (dev->gcDirtiest < 1 || pagesUsed < dev->gcPagesInUse) &&
+ yaffs_BlockNotDisqualifiedFromGC(dev, bi)) {
+ dev->gcDirtiest = dev->gcBlockFinder;
+ dev->gcPagesInUse = pagesUsed;
+ }
+ }
+
+ if(dev->gcDirtiest > 0 && dev->gcPagesInUse <= threshold)
+ selected = dev->gcDirtiest;
+ }
+
+ /*
+ * If nothing has been selected for a while, try selecting the oldest dirty
+ * because that's gumming up the works.
+ */
+
+ if(!selected && dev->param.isYaffs2 &&
+ dev->gcNotDone >= ( background ? 10 : 20)){
+ yaffs_FindOldestDirtySequence(dev);
+ if(dev->oldestDirtyBlock > 0) {
+ selected = dev->oldestDirtyBlock;
+ dev->gcDirtiest = selected;
+ dev->oldestDirtyGCs++;
+ bi = yaffs_GetBlockInfo(dev, selected);
+ dev->gcPagesInUse = bi->pagesInUse - bi->softDeletions;
+ } else
+ dev->gcNotDone = 0;
+ }
+
+ if(selected){
+ T(YAFFS_TRACE_GC,
+ (TSTR("GC Selected block %d with %d free, prioritised:%d" TENDSTR),
+ selected,
+ dev->param.nChunksPerBlock - dev->gcPagesInUse,
+ prioritised));
+
+ if(background)
+ dev->backgroundGCs++;
+ dev->gcDirtiest = 0;
+ dev->gcPagesInUse = 0;
+ dev->gcNotDone = 0;
+ if(dev->refreshSkip > 0)
+ dev->refreshSkip--;
+ } else{
+ dev->gcNotDone++;
+ T(YAFFS_TRACE_GC,
+ (TSTR("GC none: finder %d skip %d threshold %d dirtiest %d using %d oldest %d%s" TENDSTR),
+ dev->gcBlockFinder, dev->gcNotDone,
+ threshold,
+ dev->gcDirtiest, dev->gcPagesInUse,
+ dev->oldestDirtyBlock,
+ background ? " bg" : ""));
+ }
+
+ return selected;
+}
+
/* New garbage collector
* If we're very low on erased blocks then we do aggressive garbage collection
* otherwise we do "leasurely" garbage collection.
* The idea is to help clear out space in a more spread-out manner.
* Dunno if it really does anything useful.
*/
-static int yaffs_CheckGarbageCollection(yaffs_Device *dev)
+static int yaffs_CheckGarbageCollection(yaffs_Device *dev, int background)
{
- int block;
- int aggressive;
+ int aggressive = 0;
int gcOk = YAFFS_OK;
int maxTries = 0;
+ int minErased;
+ int erasedChunks;
+
int checkpointBlockAdjust;
if(dev->param.gcControl &&
(dev->param.gcControl(dev) & 1) == 0)
return YAFFS_OK;
- if (dev->isDoingGC) {
+ if (dev->gcDisable) {
/* Bail out so we don't get recursive gc */
return YAFFS_OK;
}
/* This loop should pass the first time.
- * We'll only see looping here if the erase of the collected block fails.
+ * We'll only see looping here if the collection does not increase space.
*/
do {
if (checkpointBlockAdjust < 0)
checkpointBlockAdjust = 0;
+ minErased = dev->param.nReservedBlocks + checkpointBlockAdjust + 1;
+ erasedChunks = dev->nErasedBlocks * dev->param.nChunksPerBlock;
+
/* If we need a block soon then do aggressive gc.*/
- if (dev->nErasedBlocks < (dev->param.nReservedBlocks + checkpointBlockAdjust + 2))
+ if (dev->nErasedBlocks < minErased)
aggressive = 1;
- else
- aggressive = 0;
+ else {
+ if(dev->gcSkip > 20)
+ dev->gcSkip = 20;
+ if(erasedChunks < dev->nFreeChunks/2 ||
+ dev->gcSkip < 1 ||
+ background)
+ aggressive = 0;
+ else {
+ dev->gcSkip--;
+ break;
+ }
+ }
+
+ dev->gcSkip = 5;
/* If we don't already have a block being gc'd then see if we should start another */
dev->gcChunk = 0;
}
if (dev->gcBlock < 1) {
- dev->gcBlock = yaffs_FindBlockForGarbageCollection(dev, aggressive);
+ dev->gcBlock = yaffs_FindBlockForGarbageCollection(dev, aggressive, background);
dev->gcChunk = 0;
}
- block = dev->gcBlock;
-
- if (block > 0) {
- dev->garbageCollections++;
+ if (dev->gcBlock > 0) {
+ dev->allGCs++;
if (!aggressive)
- dev->passiveGarbageCollections++;
+ dev->passiveGCs++;
T(YAFFS_TRACE_GC,
(TSTR
("yaffs: GC erasedBlocks %d aggressive %d" TENDSTR),
dev->nErasedBlocks, aggressive));
- gcOk = yaffs_GarbageCollectBlock(dev, block, aggressive);
+ gcOk = yaffs_GarbageCollectBlock(dev, dev->gcBlock, aggressive);
}
- if (dev->nErasedBlocks < (dev->param.nReservedBlocks) && block > 0) {
+ if (dev->nErasedBlocks < (dev->param.nReservedBlocks) && dev->gcBlock > 0) {
T(YAFFS_TRACE_GC,
(TSTR
("yaffs: GC !!!no reclaim!!! erasedBlocks %d after try %d block %d"
- TENDSTR), dev->nErasedBlocks, maxTries, block));
+ TENDSTR), dev->nErasedBlocks, maxTries, dev->gcBlock));
}
} while ((dev->nErasedBlocks < dev->param.nReservedBlocks) &&
- (block > 0) &&
+ (dev->gcBlock > 0) &&
(maxTries < 2));
return aggressive ? gcOk : YAFFS_OK;
}
+/*
+ * yaffs_BackgroundGarbageCollect()
+ * Garbage collects. Intended to be called from a background thread.
+ * Returns non-zero if at least half the free chunks are erased.
+ */
+int yaffs_BackgroundGarbageCollect(yaffs_Device *dev, unsigned urgency)
+{
+ int erasedChunks = dev->nErasedBlocks * dev->param.nChunksPerBlock;
+
+ T(YAFFS_TRACE_BACKGROUND, (TSTR("Background gc %u" TENDSTR),urgency));
+
+ yaffs_CheckGarbageCollection(dev, 1);
+ return erasedChunks > dev->nFreeChunks/2;
+}
+
/*------------------------- TAGS --------------------------------*/
static int yaffs_TagsMatch(const yaffs_ExtendedTags *tags, int objectId,
bi = yaffs_GetBlockInfo(dev, block);
- yaffs_UpdateOldestDirtySequence(dev,bi);
+ yaffs_UpdateOldestDirtySequence(dev, block, bi);
T(YAFFS_TRACE_DELETION,
(TSTR("line %d delete of chunk %d" TENDSTR), lyn, chunkId));
yaffs_Device *dev = in->myDev;
- yaffs_CheckGarbageCollection(dev);
+ yaffs_CheckGarbageCollection(dev,0);
/* Get the previous chunk at this location in the file if it exists.
* If it does not exist then put a zero into the tree. This creates
in == dev->rootDir || /* The rootDir should also be saved */
force) {
- yaffs_CheckGarbageCollection(dev);
+ yaffs_CheckGarbageCollection(dev,0);
yaffs_CheckObjectDetailsLoaded(in);
buffer = yaffs_GetTempBuffer(in->myDev, __LINE__);
yaffs_FlushFilesChunkCache(in);
yaffs_InvalidateWholeChunkCache(in);
- yaffs_CheckGarbageCollection(dev);
+ yaffs_CheckGarbageCollection(dev,0);
if (in->variantType != YAFFS_OBJECT_TYPE_FILE)
return YAFFS_FAIL;
* the current allocation block.
*/
- T(YAFFS_TRACE_ALWAYS,
+ T(YAFFS_TRACE_SCAN,
(TSTR("Partially written block %d detected" TENDSTR),
blk));
}
dev->chunkOffset = 0;
dev->nFreeChunks = 0;
- dev->gcBlock = -1;
+ dev->gcBlock = 0;
if (dev->param.startBlock == 0) {
dev->internalStartBlock = dev->param.startBlock + 1;
/* OK, we've finished verifying the device, lets continue with initialisation */
/* More device initialisation */
- dev->garbageCollections = 0;
- dev->passiveGarbageCollections = 0;
- dev->currentDirtyChecker = 0;
+ dev->allGCs = 0;
+ dev->passiveGCs = 0;
+ dev->oldestDirtyGCs = 0;
+ dev->backgroundGCs = 0;
+ dev->gcBlockFinder = 0;
dev->bufferedBlock = -1;
dev->doingBufferedBlockRewrite = 0;
dev->nDeletedFiles = 0;
dev->tagsEccUnfixed = 0;
dev->nErasureFailures = 0;
dev->nErasedBlocks = 0;
- dev->isDoingGC = 0;
+ dev->gcDisable= 0;
dev->hasPendingPrioritisedGCs = 1; /* Assume the worst for now, will get fixed on first GC */
YINIT_LIST_HEAD(&dev->dirtyDirectories);
dev->oldestDirtySequence = 0;
+ dev->oldestDirtyBlock = 0;
/* Initialise temporary buffers and caches. */
if (!yaffs_InitialiseTempBuffers(dev))
projects / yaffs2.git / blobdiff