Re: [PATCH][resend] perf x86 kvm-stat: support to analyze kvm msr

From: Namhyung Kim
Date: Fri Apr 23 2021 - 13:06:07 EST


Hello,

On Thu, Apr 22, 2021 at 11:33 AM Li,Rongqing <lirongqing@xxxxxxxxx> wrote:
> > Subject: [PATCH][resend] perf x86 kvm-stat: support to analyze kvm msr
> >
> > From: Lei Zhao <zhaolei27@xxxxxxxxx>
> >
> > usage:
> > - kvm stat
> > run a command and gather performance counter statistics
> >
> > - show the result:
> > perf kvm stat report --event=msr
> >
> > See the msr events:
> >
> > Analyze events for all VMs, all VCPUs:
> >
> > MSR Access Samples Samples% Time% Min Time Max Time Avg time
> >
> > 0x6e0:W 67007 98.17% 98.31% 0.59us 10.69us 0.90us ( +-
> > 0.10% )
> > 0x830:W 1186 1.74% 1.60% 0.53us 108.34us 0.82us ( +-
> > 11.02% )
> > 0x3b:R 66 0.10% 0.09% 0.56us 1.26us 0.80us ( +-
> > 3.24% )
> >
> > Total Samples:68259, Total events handled time:61150.95us.
> >
> > Signed-off-by: Li RongQing <lirongqing@xxxxxxxxx>
> > Signed-off-by: Lei Zhao <zhaolei27@xxxxxxxxx>

Acked-by: Namhyung Kim <namhyung@xxxxxxxxxx>

Thanks,
Namhyung


> > ---
> > tools/perf/arch/x86/util/kvm-stat.c | 46
> > +++++++++++++++++++++++++++++++++++
> > 1 files changed, 46 insertions(+), 0 deletions(-)
> >
> > diff --git a/tools/perf/arch/x86/util/kvm-stat.c
> > b/tools/perf/arch/x86/util/kvm-stat.c
> > index 0729204..c5dd54f 100644
> > --- a/tools/perf/arch/x86/util/kvm-stat.c
> > +++ b/tools/perf/arch/x86/util/kvm-stat.c
> > @@ -133,11 +133,56 @@ static void ioport_event_decode_key(struct
> > perf_kvm_stat *kvm __maybe_unused,
> > .name = "IO Port Access"
> > };
> >
> > + /* The time of emulation msr is from kvm_msr to kvm_entry. */ static
> > +void msr_event_get_key(struct evsel *evsel,
> > + struct perf_sample *sample,
> > + struct event_key *key)
> > +{
> > + key->key = evsel__intval(evsel, sample, "ecx");
> > + key->info = evsel__intval(evsel, sample, "write"); }
> > +
> > +static bool msr_event_begin(struct evsel *evsel,
> > + struct perf_sample *sample,
> > + struct event_key *key)
> > +{
> > + if (!strcmp(evsel->name, "kvm:kvm_msr")) {
> > + msr_event_get_key(evsel, sample, key);
> > + return true;
> > + }
> > +
> > + return false;
> > +}
> > +
> > +static bool msr_event_end(struct evsel *evsel,
> > + struct perf_sample *sample __maybe_unused,
> > + struct event_key *key __maybe_unused) {
> > + return kvm_entry_event(evsel);
> > +}
> > +
> > +static void msr_event_decode_key(struct perf_kvm_stat *kvm
> > __maybe_unused,
> > + struct event_key *key,
> > + char *decode)
> > +{
> > + scnprintf(decode, decode_str_len, "%#llx:%s",
> > + (unsigned long long)key->key,
> > + key->info ? "W" : "R");
> > +}
> > +
> > +static struct kvm_events_ops msr_events = {
> > + .is_begin_event = msr_event_begin,
> > + .is_end_event = msr_event_end,
> > + .decode_key = msr_event_decode_key,
> > + .name = "MSR Access"
> > +};
> > +
> > const char *kvm_events_tp[] = {
> > "kvm:kvm_entry",
> > "kvm:kvm_exit",
> > "kvm:kvm_mmio",
> > "kvm:kvm_pio",
> > + "kvm:kvm_msr",
> > NULL,
> > };
> >
> > @@ -145,6 +190,7 @@ struct kvm_reg_events_ops kvm_reg_events_ops[] = {
> > { .name = "vmexit", .ops = &exit_events },
> > { .name = "mmio", .ops = &mmio_events },
> > { .name = "ioport", .ops = &ioport_events },
> > + { .name = "msr", .ops = &msr_events },
> > { NULL, NULL },
> > };
> >
> > --
> > 1.7.1
>