Details : Cleanup filter group llog code, then only filter group llog will
be only created in the MDS/OST syncing process.
+Severity : normal
+Bugzilla : 15684
+Description: Procfs and llog threads access destoryed import sometimes.
+Details : Sync the import destoryed process with procfs and llog threads by
+ the import refcount and semaphore.
+
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2007-08-10 Cluster File Systems, Inc. <info@clusterfs.com>