On Fri, 2011-03-25 at 09:10 -0400, Steven Rostedt wrote: > One solution is to have this be only done on explicit trylocks. Perhaps > introduce a mutex_trylock_spin()? Then when the developer knows that > this scenario does not exist, they can convert mutex_trylocks() into > this spinning version. >
I'm not sure this is even worth it, as I'm looking at the btfs/extend-tree.c code, this is the main reason to use mutex_trylock(). I guess what you see in your benchmarks is that trylock contention happens mostly in the non-deadlock scenario. But I bet you have latencies when it does happen, but the benefit seems to out weigh it in the results. I wonder what happens if you run dbench as an RT task. -- Steve -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
