> > A longer cpu_relax() here would improve things (on arm64 this function > > is a no-op) but maybe Thomas or Will have a better idea. > > I had a pretty gross cpu_relax() implementation using wfe somewhere on > LKML, so you could try that if you can dig it up. Do you mean cpu_relax() implementation from this email [1] from Fri, 28 Jul 2017 ? I tried to rebase it on recent Linux, but it did not even boot for me. Only this was printed: [ 0.000000] Booting Linux on physical CPU 0x0000000000 [0x410fd034] [ 0 But cpu_relax() implementation from [1] fixes my problem if I use it only in irq_finalize_oneshot(). [1] https://lore.kernel.org/lkml/20170728092831.GA24839@xxxxxxx/ Zdenek Bouska -- Siemens, s.r.o Siemens Advanta Development
