On Sun, Mar 29, 2009 at 11:36:35PM +0200, Oleg Nesterov wrote: > > ... or just do that to fs_struct. After finding that there's no outside > > users. Commenst? > > This is even worse. Not only we race with our sub-threads, we race > with CLONE_FS processes. > > We can't mark fs_struct after finding that there's no outside users > lockless. Because we can't know whether this is "after" or not, we > can't trust "atomic_read(fs->count) <= n_fs". We can lock fs_struct in question, go through the threads, then mark or bail out. With cloning a reference to fs_struct protected by the same lock. FWIW, I'm not at all sure that we want atomic_t for refcount in that case... -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
