On Thu, May 2, 2013 at 7:16 PM, Colin Cross <ccr...@android.com> wrote: > This sounds the same as what ended up getting reverted in > https://lkml.org/lkml/2013/3/4/221 > I can add the WARN_ON_ONCE to all my new calls, and leave them out of > existing calls, but that seems a little odd, and will be redundant if > the lockdep call in try_to_freeze goes back in in 3.11. Do you still > want it in the new apis? > > On Thu, May 2, 2013 at 5:03 PM, Tejun Heo <t...@kernel.org> wrote: >> On Thu, May 02, 2013 at 04:55:05PM -0700, Tejun Heo wrote: >>> So, the freezable interface can't be something that people can use >>> casually. It is something which should be carefully and strategically >>> deployed where we *know* that lock dependency risks don't exist or at >>> least are acceptable. I'm a bit weary that this patch is expanding >>> the interface a lot that they now look like the equivalents of normal >>> schedule calls. Not exactly sure what to do here but can we please at >>> least have RED BOLD BLINKING comments which scream to people not to >>> use these unless they know what they're doing? >> >> Maybe we should trigger WARN_ON_ONCE() if lockdep_depth() > 0 by >> default and have ugly variants which can be used if the caller is sure >> that it's okay possibly with list of locks which are held? >> >> -- >> tejun
(sorry for the top post) I could also put the lockdep check that was reveted back into try_to_freeze(), and add a freezable_schedule_unsafe() that skips it for use in the known-unsafe users in nfs, with a big comment not to add new users of it. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
