On Tue, Aug 23, 2011 at 01:41:48PM +0200, Paolo Bonzini wrote: > On 08/23/2011 11:17 AM, Marcelo Tosatti wrote: > >>>> > typedef struct RAMList { > >>>> > + QemuMutex mutex; > >>>> > uint8_t *phys_dirty; > >>>> > QLIST_HEAD(ram, RAMBlock) blocks; > >>>> > QLIST_HEAD(, RAMBlock) blocks_mru; > >>> > >>> A comment on what the mutex protects would be good. > > Indeed, especially because Umesh wanted to use the ramlist+iothread > combo as a rw-lock: iothread = read-lock for the I/O thread, ramlist > = read-lock for the migration thread, together = exclusive (write) > lock. But I think I talked him out of this. :) It's not a bad idea > in general, it just sounds like overkill in this case. > > >And on the lock ordering. > > I think when only two locks are involved, we can always assume > iothread is outer and the other is inner. Do you agree? > > Paolo Yep. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html