PM_PSHIFT_BITS    511 fs/proc/task_mmu.c #define PM_PSHIFT_OFFSET    (PM_STATUS_OFFSET - PM_PSHIFT_BITS)
PM_PSHIFT_BITS    512 fs/proc/task_mmu.c #define PM_PSHIFT_MASK      (((1LL << PM_PSHIFT_BITS) - 1) << PM_PSHIFT_OFFSET)