summaryrefslogtreecommitdiffstats
path: root/generic/tclThreadAlloc.c
diff options
context:
space:
mode:
authordgp <dgp@users.sourceforge.net>2015-04-16 12:27:04 (GMT)
committerdgp <dgp@users.sourceforge.net>2015-04-16 12:27:04 (GMT)
commit240098bfba8eb55a1ce74fbefa3ea60b4890c480 (patch)
tree1354808ffaf3cbcbad438634ad9bcc7bfeb1d942 /generic/tclThreadAlloc.c
parentf32d7a27baaf82615453a772b3371d58909f341f (diff)
downloadtcl-240098bfba8eb55a1ce74fbefa3ea60b4890c480.zip
tcl-240098bfba8eb55a1ce74fbefa3ea60b4890c480.tar.gz
tcl-240098bfba8eb55a1ce74fbefa3ea60b4890c480.tar.bz2
Reduce the list walking by keeping lastPtr fields.zippy_fifo
Diffstat (limited to 'generic/tclThreadAlloc.c')
-rw-r--r--generic/tclThreadAlloc.c63
1 files changed, 35 insertions, 28 deletions
diff --git a/generic/tclThreadAlloc.c b/generic/tclThreadAlloc.c
index 92bec44..3267a0d 100644
--- a/generic/tclThreadAlloc.c
+++ b/generic/tclThreadAlloc.c
@@ -84,6 +84,7 @@ typedef union Block {
typedef struct Bucket {
Block *firstPtr; /* First block available */
+ Block *lastPtr; /* End of block list */
long numFree; /* Number of blocks available */
/* All fields below for accounting only */
@@ -107,6 +108,7 @@ typedef struct Cache {
Tcl_ThreadId owner; /* Which thread's cache is this? */
Tcl_Obj *firstObjPtr; /* List of free objects for thread */
int numObjects; /* Number of objects for thread */
+ Tcl_Obj *lastPtr; /* Last object in this cache */
int totalAssigned; /* Total space assigned to thread */
Bucket buckets[NBUCKETS]; /* The buckets for this thread */
} Cache;
@@ -414,6 +416,9 @@ TclpFree(
cachePtr->buckets[bucket].totalAssigned -= blockPtr->blockReqSize;
blockPtr->nextBlock = cachePtr->buckets[bucket].firstPtr;
cachePtr->buckets[bucket].firstPtr = blockPtr;
+ if (cachePtr->buckets[bucket].numFree == 0) {
+ cachePtr->buckets[bucket].lastPtr = blockPtr;
+ }
cachePtr->buckets[bucket].numFree++;
cachePtr->buckets[bucket].numInserts++;
@@ -571,11 +576,13 @@ TclThreadAllocObj(void)
if (newObjsPtr == NULL) {
Tcl_Panic("alloc: could not allocate %d new objects", numMove);
}
+ cachePtr->lastPtr = newObjsPtr + numMove - 1;
+ objPtr = cachePtr->firstObjPtr; /* NULL */
while (--numMove >= 0) {
- objPtr = &newObjsPtr[numMove];
- objPtr->internalRep.twoPtrValue.ptr1 = cachePtr->firstObjPtr;
- cachePtr->firstObjPtr = objPtr;
+ newObjsPtr[numMove].internalRep.twoPtrValue.ptr1 = objPtr;
+ objPtr = newObjsPtr + numMove;
}
+ cachePtr->firstObjPtr = newObjsPtr;
}
}
@@ -623,6 +630,9 @@ TclThreadFreeObj(
objPtr->internalRep.twoPtrValue.ptr1 = cachePtr->firstObjPtr;
cachePtr->firstObjPtr = objPtr;
+ if (cachePtr->numObjects == 0) {
+ cachePtr->lastPtr = objPtr;
+ }
cachePtr->numObjects++;
/*
@@ -729,7 +739,8 @@ MoveObjs(
* just have to update the first and last.
*/
- objPtr->internalRep.twoPtrValue.ptr1 = toPtr->firstObjPtr;
+ toPtr->lastPtr = objPtr;
+ objPtr->internalRep.twoPtrValue.ptr1 = toPtr->firstObjPtr; /* NULL */
toPtr->firstObjPtr = fromFirstObjPtr;
}
@@ -755,7 +766,7 @@ PutObjs(
int numMove)
{
int keep = fromPtr->numObjects - numMove;
- Tcl_Obj *firstPtr, *lastPtr;
+ Tcl_Obj *firstPtr, *lastPtr = NULL;
fromPtr->numObjects = keep;
firstPtr = fromPtr->firstObjPtr;
@@ -769,22 +780,21 @@ PutObjs(
lastPtr->internalRep.twoPtrValue.ptr1 = NULL;
}
- /* TODO: We could avoid this walk to lastPtr if we kept a lastPtr field */
- lastPtr = firstPtr;
- while (lastPtr->internalRep.twoPtrValue.ptr1) {
- lastPtr = lastPtr->internalRep.twoPtrValue.ptr1;
- }
-
/*
* Move all objects as a block - they are already linked to each other, we
* just have to update the first and last.
*/
Tcl_MutexLock(objLockPtr);
- lastPtr->internalRep.twoPtrValue.ptr1 = sharedPtr->firstObjPtr;
+ fromPtr->lastPtr->internalRep.twoPtrValue.ptr1 = sharedPtr->firstObjPtr;
sharedPtr->firstObjPtr = firstPtr;
+ if (sharedPtr->numObjects == 0) {
+ sharedPtr->lastPtr = fromPtr->lastPtr;
+ }
sharedPtr->numObjects += numMove;
Tcl_MutexUnlock(objLockPtr);
+
+ fromPtr->lastPtr = lastPtr;
}
/*
@@ -905,7 +915,7 @@ PutBlocks(
*/
int keep = cachePtr->buckets[bucket].numFree - numMove;
- Block *lastPtr, *firstPtr;
+ Block *lastPtr = NULL, *firstPtr;
cachePtr->buckets[bucket].numFree = keep;
firstPtr = cachePtr->buckets[bucket].firstPtr;
@@ -919,30 +929,23 @@ PutBlocks(
lastPtr->nextBlock = NULL;
}
- /*
- * firstPtr now points to the first Block to return to shared.
- */
-
- /* TODO: We could avoid this walk to lastPtr if we kept a lastPtr field */
- lastPtr = firstPtr;
- while (lastPtr->nextBlock) {
- lastPtr = lastPtr->nextBlock;
- }
-
- /*
- * lastPtr now points to the last Block to return to shared.
- */
-
/*
* Aquire the lock and place the list of blocks at the front of the shared
* cache bucket.
*/
LockBucket(cachePtr, bucket);
- lastPtr->nextBlock = sharedPtr->buckets[bucket].firstPtr;
+ cachePtr->buckets[bucket].lastPtr->nextBlock
+ = sharedPtr->buckets[bucket].firstPtr;
sharedPtr->buckets[bucket].firstPtr = firstPtr;
+ if (sharedPtr->buckets[bucket].numFree == 0) {
+ sharedPtr->buckets[bucket].lastPtr
+ = cachePtr->buckets[bucket].lastPtr;
+ }
sharedPtr->buckets[bucket].numFree += numMove;
UnlockBucket(cachePtr, bucket);
+
+ cachePtr->buckets[bucket].lastPtr = lastPtr;
}
/*
@@ -989,6 +992,8 @@ GetBlocks(
if (n >= sharedPtr->buckets[bucket].numFree) {
cachePtr->buckets[bucket].firstPtr =
sharedPtr->buckets[bucket].firstPtr;
+ cachePtr->buckets[bucket].lastPtr =
+ sharedPtr->buckets[bucket].lastPtr;
cachePtr->buckets[bucket].numFree =
sharedPtr->buckets[bucket].numFree;
sharedPtr->buckets[bucket].firstPtr = NULL;
@@ -1002,6 +1007,7 @@ GetBlocks(
blockPtr = blockPtr->nextBlock;
}
sharedPtr->buckets[bucket].firstPtr = blockPtr->nextBlock;
+ cachePtr->buckets[bucket].lastPtr = blockPtr;
blockPtr->nextBlock = NULL;
}
}
@@ -1053,6 +1059,7 @@ GetBlocks(
((char *) blockPtr + bucketInfo[bucket].blockSize);
blockPtr = blockPtr->nextBlock;
}
+ cachePtr->buckets[bucket].lastPtr = blockPtr;
blockPtr->nextBlock = NULL;
}
return 1;