[PATCH v1 0/5] KVM in-guest performance monitoring

From: Avi Kivity
Date: Wed May 11 2011 - 12:05:01 EST


This not-for-merging patchset exposes an emulated version 1 architectural
performance monitoring unit to KVM guests. The PMU is emulated using
perf_events, so the host kernel can multiplex host-wide, host-user, and the
guest on available resources.

Caveats:
- counters that have PMI (interrupt) enabled stop counting after the
interrupt is signalled. This is because we need one-shot samples
that keep counting, which perf doesn't support yet
- some combinations of INV and CMASK are not supported
- counters keep on counting in the host as well as the guest
- the RDPMC instruction and CR4.PCE bit are not yet emulated
- there is likely a bug in the implementation; running 'perf top' in
a guest that spends 80% of its time in userspace shows perf itself
as consuming almost all cpu

perf maintainers: please consider the first three patches for merging (the
first two make sense even without the rest). If you're familiar with the Intel
PMU, please review patch 5 as well - it effectively undoes all your work
of abstracting the PMU into perf_events by unabstracting perf_events into what
is hoped is a very similar PMU.

Avi Kivity (5):
perf: add context parameter to perf_event overflow handler
x86, perf: add constraints for architectural PMU v1
perf: export perf_event_refresh() to modules
KVM: Expose kvm_lapic_local_deliver()
KVM: Expose a version 1 architectural PMU to guests

arch/arm/kernel/ptrace.c | 10 +-
arch/powerpc/kernel/ptrace.c | 4 +-
arch/sh/kernel/ptrace_32.c | 5 +-
arch/x86/include/asm/kvm_host.h | 29 ++++
arch/x86/kernel/cpu/perf_event_intel.c | 23 +++-
arch/x86/kernel/kgdb.c | 2 +-
arch/x86/kernel/ptrace.c | 5 +-
arch/x86/kvm/Makefile | 2 +-
arch/x86/kvm/lapic.c | 2 +-
arch/x86/kvm/lapic.h | 1 +
arch/x86/kvm/pmu.c | 248 +++++++++++++++++++++++++++++++
arch/x86/kvm/x86.c | 16 +-
drivers/oprofile/oprofile_perf.c | 5 +-
include/linux/hw_breakpoint.h | 10 +-
include/linux/perf_event.h | 13 ++-
kernel/events/core.c | 27 +++-
kernel/events/hw_breakpoint.c | 10 +-
kernel/watchdog.c | 7 +-
samples/hw_breakpoint/data_breakpoint.c | 5 +-
19 files changed, 377 insertions(+), 47 deletions(-)
create mode 100644 arch/x86/kvm/pmu.c

--
1.7.4.3

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