On Wed, Oct 21, 2020 at 02:16:12PM -0700, Stephane Eranian wrote:
> Starting with Arch Perfmon v5, the anythread filter on generic counters may be
> deprecated. The current kernel was exporting the any filter without checking.
> On Icelake, it means you could do cpu/event=0x3c,any/ even though the filter
> does not exist. This patch corrects the problem by relying on the CPUID 0xa leaf
> function to determine if anythread is supported or not as described in the
> Intel SDM Vol3b 18.2.5.1 AnyThread Deprecation section.
>
> Signed-off-by: Stephane Eranian <[email protected]>
> ---
> arch/x86/events/intel/core.c | 20 ++++++++++++++++++++
> arch/x86/events/perf_event.h | 1 +
> arch/x86/include/asm/perf_event.h | 4 +++-
> arch/x86/kvm/cpuid.c | 4 +++-
> 4 files changed, 27 insertions(+), 2 deletions(-)
>
> diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
> index f1926e9f2143..65bf649048a6 100644
> --- a/arch/x86/events/intel/core.c
> +++ b/arch/x86/events/intel/core.c
> @@ -4220,6 +4220,16 @@ static struct attribute *intel_arch3_formats_attr[] = {
> NULL,
> };
>
> +static struct attribute *intel_arch5_formats_attr[] = {
> + &format_attr_event.attr,
> + &format_attr_umask.attr,
> + &format_attr_edge.attr,
> + &format_attr_pc.attr,
> + &format_attr_inv.attr,
> + &format_attr_cmask.attr,
> + NULL,
> +};
Instead of adding yet another (which is an exact duplicate of the
existing intel_arch_formats_attr BTW), can't we clean this up and use
is_visible() as 'demanded' by GregKH and done by Jiri here:
3d5672735b23 ("perf/x86: Add is_visible attribute_group callback for base events")
b7c9b3927337 ("perf/x86/intel: Use ->is_visible callback for default group")
baa0c83363c7 ("perf/x86: Use the new pmu::update_attrs attribute group")
And only have "any" visible for v3,v4
On Thu, Oct 22, 2020 at 1:00 AM Peter Zijlstra <[email protected]> wrote:
>
> On Wed, Oct 21, 2020 at 02:16:12PM -0700, Stephane Eranian wrote:
> > Starting with Arch Perfmon v5, the anythread filter on generic counters may be
> > deprecated. The current kernel was exporting the any filter without checking.
> > On Icelake, it means you could do cpu/event=0x3c,any/ even though the filter
> > does not exist. This patch corrects the problem by relying on the CPUID 0xa leaf
> > function to determine if anythread is supported or not as described in the
> > Intel SDM Vol3b 18.2.5.1 AnyThread Deprecation section.
> >
> > Signed-off-by: Stephane Eranian <[email protected]>
> > ---
> > arch/x86/events/intel/core.c | 20 ++++++++++++++++++++
> > arch/x86/events/perf_event.h | 1 +
> > arch/x86/include/asm/perf_event.h | 4 +++-
> > arch/x86/kvm/cpuid.c | 4 +++-
> > 4 files changed, 27 insertions(+), 2 deletions(-)
> >
> > diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
> > index f1926e9f2143..65bf649048a6 100644
> > --- a/arch/x86/events/intel/core.c
> > +++ b/arch/x86/events/intel/core.c
> > @@ -4220,6 +4220,16 @@ static struct attribute *intel_arch3_formats_attr[] = {
> > NULL,
> > };
> >
> > +static struct attribute *intel_arch5_formats_attr[] = {
> > + &format_attr_event.attr,
> > + &format_attr_umask.attr,
> > + &format_attr_edge.attr,
> > + &format_attr_pc.attr,
> > + &format_attr_inv.attr,
> > + &format_attr_cmask.attr,
> > + NULL,
> > +};
>
> Instead of adding yet another (which is an exact duplicate of the
> existing intel_arch_formats_attr BTW), can't we clean this up and use
> is_visible() as 'demanded' by GregKH and done by Jiri here:
>
> 3d5672735b23 ("perf/x86: Add is_visible attribute_group callback for base events")
> b7c9b3927337 ("perf/x86/intel: Use ->is_visible callback for default group")
> baa0c83363c7 ("perf/x86: Use the new pmu::update_attrs attribute group")
>
> And only have "any" visible for v3,v4
Sure, let me resubmit with these changes.