| Message ID | 20220525130554.2614394-1-farosas@linux.ibm.com |
|---|---|
| Headers | show |
| Series | KVM: PPC: Book3S HV: Update debug timing code | expand |
On Wed, 25 May 2022 10:05:49 -0300, Fabiano Rosas wrote: > We have some debug information at /sys/kernel/debug/kvm/<vm>/vcpu#/timings > which shows the time it takes to run various parts of the code. > > That infrastructure was written in the P8 timeframe and wasn't updated > along with the guest entry point changes for P9. > > Ideally we would be able to just add new/different accounting points > to the code as it changes over time but since the P8 and P9 entry > points are different code paths we first need to separate them from > each other. This series alters KVM Kconfig to make that distinction. > > [...] Applied to powerpc/topic/ppc-kvm. [1/5] KVM: PPC: Book3S HV: Fix "rm_exit" entry in debugfs timings https://git.kernel.org/powerpc/c/9981bace85d816ed8724ac46e49285e8488d29e6 [2/5] KVM: PPC: Book3S HV: Add a new config for P8 debug timing https://git.kernel.org/powerpc/c/3f8ed993be3cf154a91d9ab5e80470c6c755adbe [3/5] KVM: PPC: Book3S HV: Decouple the debug timing from the P8 entry path https://git.kernel.org/powerpc/c/c3fa64c99c61d99631a8e06a6cf991c35c98ec7d [4/5] KVM: PPC: Book3S HV: Expose timing functions to module code https://git.kernel.org/powerpc/c/2861c827286fb6646f6b6caee418efd99992097c [5/5] KVM: PPC: Book3S HV: Provide more detailed timings for P9 entry path https://git.kernel.org/powerpc/c/b44bb1b7cbbae66ec73868f5fbd57c54f0612d1c cheers
We have some debug information at /sys/kernel/debug/kvm/<vm>/vcpu#/timings which shows the time it takes to run various parts of the code. That infrastructure was written in the P8 timeframe and wasn't updated along with the guest entry point changes for P9. Ideally we would be able to just add new/different accounting points to the code as it changes over time but since the P8 and P9 entry points are different code paths we first need to separate them from each other. This series alters KVM Kconfig to make that distinction. Currently: CONFIG_KVM_BOOK3S_HV_EXIT_TIMING - timing infrastructure in asm (P8 only) timing infrastructure in C (P9 only) generic timing variables (P8/P9) debugfs code timing points for P8 After this series: CONFIG_KVM_BOOK3S_HV_EXIT_TIMING - generic timing variables (P8/P9) debugfs code CONFIG_KVM_BOOK3S_HV_P8_TIMING - timing infrastructure in asm (P8 only) timing points for P8 CONFIG_KVM_BOOK3S_HV_P9_TIMING - timing infrastructure in C (P9 only) timing points for P9 The new Kconfig rules are: a) CONFIG_KVM_BOOK3S_HV_P8_TIMING selects CONFIG_KVM_BOOK3S_HV_EXIT_TIMING, resulting in the previous behavior. Tested on P8. b) CONFIG_KVM_BOOK3S_HV_P9_TIMING selects CONFIG_KVM_BOOK3S_HV_EXIT_TIMING, resulting in the new behavior. Tested on P9. c) CONFIG_KVM_BOOK3S_HV_P8_TIMING and CONFIG_KVM_BOOK3S_HV_P9_TIMING are mutually exclusive. If both are set, P9 takes precedence. Fabiano Rosas (5): KVM: PPC: Book3S HV: Fix "rm_exit" entry in debugfs timings KVM: PPC: Book3S HV: Add a new config for P8 debug timing KVM: PPC: Book3S HV: Decouple the debug timing from the P8 entry path KVM: PPC: Book3S HV: Expose timing functions to module code KVM: PPC: Book3S HV: Provide more detailed timings for P9 entry path arch/powerpc/include/asm/kvm_host.h | 10 +++++++ arch/powerpc/kernel/asm-offsets.c | 2 +- arch/powerpc/kvm/Kconfig | 19 ++++++++++++- arch/powerpc/kvm/book3s_hv.c | 26 ++++++++++++++++-- arch/powerpc/kvm/book3s_hv.h | 10 +++++++ arch/powerpc/kvm/book3s_hv_p9_entry.c | 36 +++++-------------------- arch/powerpc/kvm/book3s_hv_rmhandlers.S | 24 ++++++++--------- 7 files changed, 82 insertions(+), 45 deletions(-)