On Tue, Mar 31, 2009 at 11:31 AM, krushnaal pai <krisonearth@xxxxxxxxx> wrote: > in kernel 2.6.11 > to retrieve a particular file the kernel calls d_lookup to check cache but > if it is not found in dcache ,kernel calls real_lookup to search the hard > disk. > however inside real_lookup the kernel again calls d_lookup . can someone plz > explain why? Because while you were waiting/sleeping for semaphore to be acquired. Someone else might have actually read the contents into dentry cache. So, why do a lookup! Just to speed things up, it is a clever trick. Comments tell it. Thanks, --Pradeep > -- Pradeep -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ