On Fri, 2007-09-28 at 13:11 +1000, Nick Piggin wrote: > On Friday 28 September 2007 17:42, Peter Zijlstra wrote: > > Replace raw TestSetPageLocked() usage with trylock_page() > > I have such a thing queued too, for the lock bitops patches for when 2.6.24 > opens, Andrew promises me :). > > I guess they should be identical, except I don't like doing trylock_page in > place of SetPageLocked, for memory ordering performance and aesthetic > reasons... I've got an init_page_locked (or set_page_locked... I can't > remember, the patch is at home).
Sure, that might work, or we could just make it so that add_to_*_cache is never passed an unlocked page. But sure... > Fine idea to lockdep the page lock, anyway. Does it show up any of the > buffered write deadlock possibilities? :) Not yet, it might just be that the concessions done to annotate this type of lock were too severe. What I basically did was treat all the page locks as a single recursive lock. > buffer lock is another notable bit-mutex that might be converted (I have > the patch to do the similar nice !tas->trylock conversion for that too). I > think it is used widely enough by tricky code that it would be useful to > annotate as well. Not at all familiar with that lock, but yeah, we could have a look at doing that too. > Unfortunately we can't convert bit_spinlock.h easily, I guess? Yeah, the space constraints make that rather hard. Each of these locks needs some form of external meta-data. For the page lock I used one lock instance per file system type. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
