From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paolo Bonzini Date: Tue, 11 May 2021 08:38:50 +0000 Subject: Re: [PATCH v4 0/4] KVM statistics data fd-based binary interface Message-Id: List-Id: References: <20210429203740.1935629-1-jingzhangos@google.com> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Jing Zhang , KVM , KVMARM , LinuxMIPS , KVMPPC , LinuxS390 , Linuxkselftest , Marc Zyngier , James Morse , Julien Thierry , Suzuki K Poulose , Will Deacon , Huacai Chen , Aleksandar Markovic , Thomas Bogendoerfer , Paul Mackerras , Christian Borntraeger , Janosch Frank , David Hildenbrand , Cornelia Huck , Claudio Imbrenda , Sean Christopherson , Vitaly Kuznetsov , Jim Mattson , Peter Shier , Oliver Upton , David Rientjes , Emanuele Giuseppe Esposito On 10/05/21 20:57, Jing Zhang wrote: > Hi Paolo, > > On Thu, Apr 29, 2021 at 3:37 PM Jing Zhang wrote: >> >> This patchset provides a file descriptor for every VM and VCPU to read >> KVM statistics data in binary format. >> It is meant to provide a lightweight, flexible, scalable and efficient >> lock-free solution for user space telemetry applications to pull the >> statistics data periodically for large scale systems. The pulling >> frequency could be as high as a few times per second. >> In this patchset, every statistics data are treated to have some >> attributes as below: >> * architecture dependent or common >> * VM statistics data or VCPU statistics data >> * type: cumulative, instantaneous, >> * unit: none for simple counter, nanosecond, microsecond, >> millisecond, second, Byte, KiByte, MiByte, GiByte. Clock Cycles >> Since no lock/synchronization is used, the consistency between all >> the statistics data is not guaranteed. That means not all statistics >> data are read out at the exact same time, since the statistics date >> are still being updated by KVM subsystems while they are read out. >> >> --- >> >> * v3 -> v4 >> - Rebase to kvm/queue, commit 9f242010c3b4 ("KVM: avoid "deadlock" >> between install_new_memslots and MMU notifier") >> - Use C-stype comments in the whole patch >> - Fix wrong count for x86 VCPU stats descriptors >> - Fix KVM stats data size counting and validity check in selftest >> >> * v2 -> v3 >> - Rebase to kvm/queue, commit edf408f5257b ("KVM: avoid "deadlock" >> between install_new_memslots and MMU notifier") >> - Resolve some nitpicks about format >> >> * v1 -> v2 >> - Use ARRAY_SIZE to count the number of stats descriptors >> - Fix missing `size` field initialization in macro STATS_DESC >> >> [1] https://lore.kernel.org/kvm/20210402224359.2297157-1-jingzhangos@google.com >> [2] https://lore.kernel.org/kvm/20210415151741.1607806-1-jingzhangos@google.com >> [3] https://lore.kernel.org/kvm/20210423181727.596466-1-jingzhangos@google.com >> >> --- >> >> Jing Zhang (4): >> KVM: stats: Separate common stats from architecture specific ones >> KVM: stats: Add fd-based API to read binary stats data >> KVM: stats: Add documentation for statistics data binary interface >> KVM: selftests: Add selftest for KVM statistics data binary interface >> >> Documentation/virt/kvm/api.rst | 171 ++++++++ >> arch/arm64/include/asm/kvm_host.h | 9 +- >> arch/arm64/kvm/guest.c | 42 +- >> arch/mips/include/asm/kvm_host.h | 9 +- >> arch/mips/kvm/mips.c | 67 ++- >> arch/powerpc/include/asm/kvm_host.h | 9 +- >> arch/powerpc/kvm/book3s.c | 68 +++- >> arch/powerpc/kvm/book3s_hv.c | 12 +- >> arch/powerpc/kvm/book3s_pr.c | 2 +- >> arch/powerpc/kvm/book3s_pr_papr.c | 2 +- >> arch/powerpc/kvm/booke.c | 63 ++- >> arch/s390/include/asm/kvm_host.h | 9 +- >> arch/s390/kvm/kvm-s390.c | 133 +++++- >> arch/x86/include/asm/kvm_host.h | 9 +- >> arch/x86/kvm/x86.c | 71 +++- >> include/linux/kvm_host.h | 132 +++++- >> include/linux/kvm_types.h | 12 + >> include/uapi/linux/kvm.h | 50 +++ >> tools/testing/selftests/kvm/.gitignore | 1 + >> tools/testing/selftests/kvm/Makefile | 3 + >> .../testing/selftests/kvm/include/kvm_util.h | 3 + >> .../selftests/kvm/kvm_bin_form_stats.c | 380 ++++++++++++++++++ >> tools/testing/selftests/kvm/lib/kvm_util.c | 11 + >> virt/kvm/kvm_main.c | 237 ++++++++++- >> 24 files changed, 1415 insertions(+), 90 deletions(-) >> create mode 100644 tools/testing/selftests/kvm/kvm_bin_form_stats.c >> >> >> base-commit: 9f242010c3b46e63bc62f08fff42cef992d3801b >> -- >> 2.31.1.527.g47e6f16901-goog >> > > Do I need to send another version for this? No, the merge window has just finished and I wanted to flush the dozens of bugfix patches that I had. I'll get to it shortly. Paolo