Flags needs to be collected under lock before checking;
Otherwise a race with other close+open could change the fd
mode and may result in an write failure with EACCESS.

Signed-off-by: Venkateswararao Jujjuri "<jvrao@linux.vnet.ibm.com>
Revert "Create separate lru gc thread when fd caching is disabled."

This reverts commit dc1da9986843ffd2962c3b0612a9654dfa0df094.

Investigation proved that the previous commit is needed.
Though we don't need to process fds if the cache_fds are disabled,
but moving cached entries from LRU1 to LRU2, are needed to recycle
them properly.

Signed-off-by: Venkateswararao Jujjuri (JV) <jvrao@linux.vnet.ibm.com>
Make sure that we process LRU1 and LRU2 cache even if fd cache is
disabled.

Signed-off-by: Venkateswararao Jujjuri "<jvrao@linux.vnet.ibm.com>
Set extremis flag in lru_thread only if fd cache is enabled.

Signed-off-by: Venkateswararao Jujjuri "<jvrao@linux.vnet.ibm.com>
Merge branch 'tp/ibm_next_S1043167' into ibm_next_tmp