From 537592f6bbda0c659c25ae7068f50504e2a5e116 Mon Sep 17 00:00:00 2001 From: Jeffrey Altman Date: Sat, 3 Sep 2011 21:07:13 -0400 Subject: [PATCH] Windows: correct cm_buf use of Head/Tail queues The buffer free list least recently used queue has both head and tail points. Use the proper versions of the queue mgmt functions and do not handle edge cases as special cases. Change-Id: I570682ef1cd6801f1467c4b1af40ae6591a33862 Reviewed-on: http://gerrit.openafs.org/5354 Tested-by: BuildBot Reviewed-by: Jeffrey Altman Tested-by: Jeffrey Altman --- src/WINNT/afsd/cm_buf.c | 40 ++++++++++++++++------------------------ 1 file changed, 16 insertions(+), 24 deletions(-) diff --git a/src/WINNT/afsd/cm_buf.c b/src/WINNT/afsd/cm_buf.c index ceba954014..483c0c2f17 100644 --- a/src/WINNT/afsd/cm_buf.c +++ b/src/WINNT/afsd/cm_buf.c @@ -164,11 +164,9 @@ void buf_ReleaseLocked(cm_buf_t *bp, afs_uint32 writeLocked) if (bp->refCount == 0 && !(bp->qFlags & CM_BUF_QINLRU)) { - osi_QAdd((osi_queue_t **) &cm_data.buf_freeListp, &bp->q); - - /* watch for transition from empty to one element */ - if (!cm_data.buf_freeListEndp) - cm_data.buf_freeListEndp = cm_data.buf_freeListp; + osi_QAddH( (osi_queue_t **) &cm_data.buf_freeListp, + (osi_queue_t **) &cm_data.buf_freeListEndp, + &bp->q); _InterlockedOr(&bp->qFlags, CM_BUF_QINLRU); } @@ -204,11 +202,9 @@ void buf_Release(cm_buf_t *bp) lock_ObtainWrite(&buf_globalLock); if (bp->refCount == 0 && !(bp->qFlags & CM_BUF_QINLRU)) { - osi_QAdd((osi_queue_t **) &cm_data.buf_freeListp, &bp->q); - - /* watch for transition from empty to one element */ - if (!cm_data.buf_freeListEndp) - cm_data.buf_freeListEndp = cm_data.buf_freeListp; + osi_QAddH( (osi_queue_t **) &cm_data.buf_freeListp, + (osi_queue_t **) &cm_data.buf_freeListEndp, + &bp->q); _InterlockedOr(&bp->qFlags, CM_BUF_QINLRU); } lock_ReleaseWrite(&buf_globalLock); @@ -483,17 +479,15 @@ long buf_Init(int newFile, cm_buf_ops_t *opsp, afs_uint64 nbuffers) bp->allp = cm_data.buf_allp; cm_data.buf_allp = bp; - osi_QAdd((osi_queue_t **)&cm_data.buf_freeListp, &bp->q); + osi_QAddH( (osi_queue_t **) &cm_data.buf_freeListp, + (osi_queue_t **) &cm_data.buf_freeListEndp, + &bp->q); _InterlockedOr(&bp->qFlags, CM_BUF_QINLRU); lock_InitializeMutex(&bp->mx, "Buffer mutex", LOCK_HIERARCHY_BUFFER); /* grab appropriate number of bytes from aligned zone */ bp->datap = data; - /* setup last buffer pointer */ - if (i == 0) - cm_data.buf_freeListEndp = bp; - /* next */ bp++; data += cm_data.buf_blockSize; @@ -1089,17 +1083,15 @@ long buf_GetNewLocked(struct cm_scache *scp, osi_hyper_t *offsetp, cm_req_t *req cm_data.buf_fileHashTablepp[i] = bp; } - /* we should move it from the lru queue. It better still be there, + /* we should remove it from the lru queue. It better still be there, * since we've held the global (big) lock since we found it there. */ osi_assertx(bp->qFlags & CM_BUF_QINLRU, "buf_GetNewLocked: LRU screwup"); - if (cm_data.buf_freeListEndp == bp) { - /* we're the last guy in this queue, so maintain it */ - cm_data.buf_freeListEndp = (cm_buf_t *) osi_QPrev(&bp->q); - } - osi_QRemove((osi_queue_t **) &cm_data.buf_freeListp, &bp->q); + osi_QRemoveHT( (osi_queue_t **) &cm_data.buf_freeListp, + (osi_queue_t **) &cm_data.buf_freeListEndp, + &bp->q); _InterlockedAnd(&bp->qFlags, ~CM_BUF_QINLRU); /* prepare to return it. Give it a refcount */ @@ -1273,9 +1265,9 @@ long buf_Get(struct cm_scache *scp, osi_hyper_t *offsetp, cm_req_t *reqp, cm_buf */ lock_ObtainWrite(&buf_globalLock); if (bp->qFlags & CM_BUF_QINLRU) { - if (cm_data.buf_freeListEndp == bp) - cm_data.buf_freeListEndp = (cm_buf_t *) osi_QPrev(&bp->q); - osi_QRemove((osi_queue_t **) &cm_data.buf_freeListp, &bp->q); + osi_QRemoveHT( (osi_queue_t **) &cm_data.buf_freeListp, + (osi_queue_t **) &cm_data.buf_freeListEndp, + &bp->q); _InterlockedAnd(&bp->qFlags, ~CM_BUF_QINLRU); } lock_ReleaseWrite(&buf_globalLock);