On Wed, May 25, 2022 at 04:07:47PM +0200, Stefan Wahren wrote: > Hi Marcelo, > > Am 25.05.22 um 15:56 schrieb Marcelo Tosatti: > > On Mon, May 23, 2022 at 09:09:07AM +0200, Sebastian Andrzej Siewior wrote: > > > On 2022-05-22 01:22:00 [+0200], Stefan Wahren wrote: > > > > Hi, > > > Hi, > > > > > > > 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]. > > > What about > > > https://lore.kernel.org/all/YmrWK%2FKoU1zrAxPI@xxxxxxxxxxx/ > > > > > > Sebastian > > Stefan, > > > > Can you please try the patch above ? > > this was the same as Paul send. I think i need more time for investigation, > maybe there is an issue with the application. To clarify: they are not the same patches. > > All i noticed so far is that in good case the CPU usage is around ~ 60 % and > higher, while in bad case the CPU is almost idle. Also the issue is not > reproducible with arm64/defconfig. > > > > > > > > > _______________________________________________ > > linux-arm-kernel mailing list > > linux-arm-kernel@xxxxxxxxxxxxxxxxxxx > > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel > >
