On Sat, Oct 31, 2015 at 02:23:31PM -0700, Linus Torvalds wrote: > The other stuff we probably can't do all that much about. Unless we > decide to go for some complicated lockless optimistic file descriptor > allocation scheme with retry-on-failure instead of locks. Which I'm > sure is possible, but I'm equally sure is painful. The interesting part is dup2() - we'd have to do something like serialize against other dup2 was_claimed = atomically set and test bit in bitmap if was_claimed tofree = fdt->fd[fd]; if (!tofree) fail with EBUSY install into ->fd[...] end of critical area in there; __alloc_fd() could be made retry-on-failure, but I don't see how to cope with dup2 vs. dup2 without an explicit exclusion. -- 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
