fix function ustime
fix function ustime

yoonkiss/fMBT,violep01/fMBT,01org/fMBT,mixu-/fMBT,yoonkiss/fMBT,mixu-/fMBT,01org/fMBT,violep01/fMBT,yoonkiss/fMBT,violep01/fMBT,violep01/fMBT,mixu-/fMBT,01org/fMBT,mixu-/fMBT,yoonkiss/fMBT,violep01/fMBT,01org/fMBT,yoonkiss/fMBT,01org/fMBT,mixu-/fMBT