On Fri, 2012-07-13 at 08:50 -0400, Chris Mason wrote: > There is also a chunk of code in btrfs_clear_path_blocking that makes > sure to strictly honor top down locking order during the conversion. It > only does this when lockdep is enabled because in non-RT kernels we > don't need to worry about it. For RT we'll want to enable that as well.
Hm, _seems_ that alone is enough prevent deadlock. Throughput really sucks though. The other bits of my stab bump throughput for dbench 128 from ~200 mb/s to ~360 mb/s (appears it's the paranoid trylock loops). ext3 does 775 mb/s with the same kernel. Or, dbench 8 on ext3 gives ~1800 mb/s and ~480 mb/s btrfs. Not exactly wonderful. Hohum, guess I'll wait and see what your patch looks like. I bet it'll work a lot better than mine does :) -Mike -- 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/
