Hey Coly, this is a fragment from a larger patch series - I wanted to send it out to you now for review because it changes the bcache sysfs interface for time_stats. This series takes the time_stats code from bcachefs (which has some additional improvements), moves it to lib/ converts bcache to use it (otherwise we get clashes with the time_stats name) - and uses it for some really cool new latency instrumentation. These patches won't apply/build, full patch series for any interested is here: https://evilpiepirate.org/git/bcachefs.git/log/?h=alloc_tags
