fix(mac): new metaReaderReleaseLock api to keep reader's buffer

source/dnode/vnode/inc/vnode.h

@@ -94,6 +94,7 @@ typedef struct SMetaEntry  SMetaEntry;
 #define META_READER_NOLOCK 0x1
 
 void        metaReaderInit(SMetaReader *pReader, SMeta *pMeta, int32_t flags);
+void        metaReaderReleaseLock(SMetaReader *pReader);
 void        metaReaderClear(SMetaReader *pReader);
 int32_t     metaGetTableEntryByUid(SMetaReader *pReader, tb_uid_t uid);
 int         metaGetTableEntryByName(SMetaReader *pReader, const char *name);

source/dnode/vnode/src/meta/metaQuery.c

@@ -24,6 +24,13 @@ void metaReaderInit(SMetaReader *pReader, SMeta *pMeta, int32_t flags) {
   }
 }
 
+void metaReaderReleaseLock(SMetaReader *pReader) {
+  if (pReader->pMeta && !(pReader->flags & META_READER_NOLOCK)) {
+    metaULock(pReader->pMeta);
+    pReader->flags |= META_READER_NOLOCK;
+  }
+}
+
 void metaReaderClear(SMetaReader *pReader) {
   if (pReader->pMeta && !(pReader->flags & META_READER_NOLOCK)) {
     metaULock(pReader->pMeta);

source/libs/executor/src/scanoperator.c

@@ -429,6 +429,8 @@ int32_t addTagPseudoColumnData(SReadHandle* pHandle, SExprInfo* pPseudoExpr, int
     return terrno;
   }
 
+  metaReaderReleaseLock(&mr);
+
   for (int32_t j = 0; j < numOfPseudoExpr; ++j) {
     SExprInfo* pExpr = &pPseudoExpr[j];