On Friday 19 November 2004 12:10 pm, Ming Zhang wrote: > I am reading dm-snap.c and found that in register_snapshot(), > http://lxr.linux.no/source/drivers/md/dm-snap.c?v=2.6.8.1#L159, > the kmalloc is called with rwsem held. I am not sure if this is a good > one since kmalloc may sleep as well. It's a semaphore, not a spinlock. Sleeping is allowed while holding a semaphore, since other threads waiting on the semaphore are also rescheduled (instead of just spinning). -- Kevin Corry kevcorry@xxxxxxxxxx http://evms.sourceforge.net/