On 12/29/23 08:52, Jens Axboe wrote: > On 12/29/23 9:41 AM, Gautam Menghani wrote: >> Convert the null_blk driver to use the xarray API instead of radix tree >> API. >> >> Testing: >> Used blktests test suite (block and zbd suites) to test the current >> null_blk driver and null_blk driver with this patch applied. The tests >> results in both the instances were the same. > What's the purpose of the change? > > One thing that always annoys me slightly with xarray is the implied > locking. So now you're grabbing two locks rather than just utilizing the > lock that was already held. I think a better transformation would be to > first change the locking to be closer to the lookup and deletion, and > then convert to xarray and now being able to drop that other lock. Just > doing a blind conversion like this without potentially understanding the > details of it is not a good idea, imho. > I agree xarray is a better data structure than radix tree w.r.t. what we did for brd, but I'm really not sure what it will buy for a testing driver like null_blk unless it is used in production somewhere where radix trees are not sufficient, but I've not seen that case ... -ck
