[TLDR: I'm adding this regression report to the list of tracked regressions; all text from me you find below is based on a few templates paragraphs you might have encountered already already in similar form.] Hi, this is your Linux kernel regression tracker. On 22.05.22 01:22, Stefan Wahren wrote: > > while testing the staging/vc04_services/interface/vchiq_arm driver with > my Raspberry Pi 3 B+ (multi_v7_defconfig) i noticed a huge performance > regression since [ff042f4a9b050895a42cae893cc01fa2ca81b95c] mm: > lru_cache_disable: replace work queue synchronization with synchronize_rcu > > Usually i run "vchiq_test -f 1" to see the driver is still working [1]. > > Before commit: > > real 0m1,500s > user 0m0,068s > sys 0m0,846s > > After commit: > > real 7m11,449s > user 0m2,049s > sys 0m0,023s Thanks for the report. To be sure below issue doesn't fall through the cracks unnoticed, I'm adding it to regzbot, my Linux kernel regression tracking bot: #regzbot ^introduced ff042f4a9b050895a42cae893cc01fa2ca81b95 #regzbot title mm: chiq_test runs 7 minutes instead of ~ 1 second. #regzbot ignore-activity This isn't a regression? This issue or a fix for it are already discussed somewhere else? It was fixed already? You want to clarify when the regression started to happen? Or point out I got the title or something else totally wrong? Then just reply -- ideally with also telling regzbot about it, as explained here: https://linux-regtracking.leemhuis.info/tracked-regression/ Reminder for developers: When fixing the issue, add 'Link:' tags pointing to the report (the mail this one replied to), as the kernel's documentation call for; above page explains why this is important for tracked regressions. Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat) P.S.: As the Linux kernel's regression tracker I deal with a lot of reports and sometimes miss something important when writing mails like this. If that's the case here, don't hesitate to tell me in a public reply, it's in everyone's interest to set the public record straight.
