> Il giorno 14 gen 2024, alle ore 21:38, Ale Crismani <ale.crismani@xxxxxxxxxxxxxx> ha scritto: > > > >> Il giorno 14 gen 2024, alle ore 06:30, David Wang <00107082@xxxxxxx> ha scritto: >> >> >> At 2024-01-14 02:24:07, "Jozsef Kadlecsik" <kadlec@xxxxxxxxxxxxxxxxx> wrote: >>> On Thu, 11 Jan 2024, David Wang wrote: >>> >>>> I tested the patch with code stressing swap->destroy->create->add 10000 >>>> times, the performance regression still happens, and now it is >>>> ip_set_destroy. (I pasted the test code at the end of this mail) >> >>>> >>>> They all call wait_for_completion, which may sleep on something on >>>> purpose, I guess... >>> >>> That's OK because ip_set_destroy() calls rcu_barrier() which is needed to >>> handle flush in list type of sets. >>> >>> However, rcu_barrier() with call_rcu() together makes multiple destroys >>> one after another slow. But rcu_barrier() is needed for list type of sets >>> only and that can be handled separately. So could you test the patch >>> below? According to my tests it is even a little bit faster than the >>> original code before synchronize_rcu() was added to swap. >> >> Confirmed~! This patch does fix the performance regression in my case. >> >> Hope it can fix ale.crismani@xxxxxxxxxxxxxx's original issue. >> >> >> >> Thanks~ >> David > > > Thanks for all the help on this, I'll try the patch tomorrow hopefully and will report back! > > best wishes, > Ale I applied the patch on 6.1.y on top of 875ee3a and I can confirm it fixes the performance issues in our case too. Thanks once more for having looked at this! Ale
