Hi Rezki, thanks so much for your review. Exactly, your suggestions could effectively enhance the maintainability and readability of this code change as well as the whole vmalloc implementation. To avoid the partial initialization issue, we are trying to refine this patch by separating insert_map_area(), the insertion of VA into the tree, from alloc_map_area(), so that setup_vmalloc_vm() could be invoked between them. However, our initial trial ran into a boot-time error, which we are still debugging, and it may take a little bit longer than expected as the coming week is the public holiday of Lunar New Year in China. We will share with you the latest version of patch once ready for your review. In the performance test, we firstly build stress-ng by following the instructions from https://github.com/ColinIanKing/stress-ng, and then launch the stressor for pthread (--pthread) for 30 seconds (-t 30) via the below command: ./stress-ng -t 30 --metrics-brief --pthread -1 --no-rand-seed The aggregated count of spawned threads per second (Bogo ops/s) is taken as the score of this workload. We evaluated the performance impact of this patch on the Ice Lake server with 40, 80, 120 and 160 online cores respectively. And as is shown in below figure, with the expansion of online cores, this patch could relieve the increasingly severe lock contention and achieve quite significant performance improvement of around 5.5% at 160 cores. vcpu number 40 80 120 160 patched/original 100.5% 100.8% 105.2% 105.5% Thanks again for your help and please let us know if more details are needed.
