On 9/2/20 6:26 AM, Ming Lei wrote: > Hi, > > The 1st patch removes memory footprint of percpu_ref in fast path > from 7 words to 2 words, since it is often used in fast path and > embedded in user struct. > > The 2nd patch moves .q_usage_counter to 1st cacheline of > 'request_queue'. > > Simple test on null_blk shows ~2% IOPS boost on one 16cores(two threads > per core) machine, dual socket/numa. > > V2: > - pass 'gfp' to kzalloc() for fixing block/027 failure reported by > kernel test robot > - protect percpu_ref_is_zero() with destroying percpu-refcount by > spin lock > > Ming Lei (2): > percpu_ref: reduce memory footprint of percpu_ref in fast path > block: move 'q_usage_counter' into front of 'request_queue' Applied, thanks. -- Jens Axboe
