Re: [PATCH v5 0/5] perf/x86: Some minor changes to support guest Arch LBR

[Like Xu]

Em, does anyone want to review these minor changes？

I believe some of them solve the real problem.

On 2021/4/6 11:20, Like Xu wrote:
> Hi all, do we have any comments on this patch set?
>
> On 2021/3/26 9:19, Like Xu wrote:
> > Hi Peter,
> >
> > Please help review these minor perf/x86 changes in this patch set,
> > and we need some of them to support Guest Architectural LBR in KVM.
> >
> > This version keeps reserve_lbr_buffers() as is because the LBR xsave
> > buffer is a per-CPU buffer, not a per-event buffer. We only need to
> > allocate the buffer once when initializing the first event.
> >
> > If you are interested in the KVM emulation, please check
> > https://lore.kernel.org/kvm/20210314155225.206661-1-like.xu@xxxxxxxxxxxxxxx/
> >
> > Please check more details in each commit and feel free to comment.
> >
> > Previous:
> > https://lore.kernel.org/lkml/20210322060635.821531-1-like.xu@xxxxxxxxxxxxxxx/ 
> >
> >
> > v4->v5 Changelog:
> > - Add "Tested-by: Kan Liang"
> > - Make the commit message simpler
> > - Make check_msr() to ignore msr==0
> > - Use kmem_cache_alloc_node() [Namhyung]
> >
> > Like Xu (5):
> >    perf/x86/intel: Fix the comment about guest LBR support on KVM
> >    perf/x86/lbr: Simplify the exposure check for the LBR_INFO registers
> >    perf/x86: Skip checking MSR for MSR 0x000
> >    perf/x86/lbr: Move cpuc->lbr_xsave allocation out of sleeping region
> >    perf/x86: Move ARCH_LBR_CTL_MASK definition to include/asm/msr-index.h
> >
> >   arch/x86/events/core.c           |  8 +++++---
> >   arch/x86/events/intel/bts.c      |  2 +-
> >   arch/x86/events/intel/core.c     |  7 +++----
> >   arch/x86/events/intel/lbr.c      | 29 ++++++++++++++++++-----------
> >   arch/x86/events/perf_event.h     |  8 +++++++-
> >   arch/x86/include/asm/msr-index.h |  1 +
> >   6 files changed, 35 insertions(+), 20 deletions(-)