Le vendredi 08 octobre 2010 Ã 06:03 -0400, Christoph Hellwig a Ãcrit : > On Fri, Oct 08, 2010 at 10:56:58AM +0100, Al Viro wrote: > > FWIW, that one is begging to be split; what I mean is that there are > > two classes of callers; ones that will set i_ino themselves anyway > > and ones that really want i_ino invented. Two functions? > > There's no reason to add i_ino before adding it to the per-sb list, > we don't do so either for inodes acquired via iget. The fix is simply > to stop assigning i_ino in new_inode and call the helper to get it in > the place that need it after the call to new_inode. Later we can > even move to a lazy assignment scheme where needed. I'd also really > like to get a grip on why the simple counters if fine for some > filesystems while we need iunique() for others. If iunique() was scalable, sockets could use it, so that we can have hard guarantee two sockets on machine dont have same inum. A reasonable compromise here is to use a simple and scalable allocator, and take the risk two sockets have same inum. While it might break some applications playing fstats() games, on sockets, current schem is vastly faster. I worked with machines with millions of opened socket concurrently, iunique() was not an option, and application didnt care of possible inum clash. For disk files, inum _must_ be unique per fs, for sockets, its only if you want strict compliance to some standards. -- 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
