Re: perf stat issue with 7.0.0rc3

[Leo Yan <leo.yan@arm.com>]

On Fri, Mar 13, 2026 at 02:13:18PM +0100, Thomas Richter wrote:
> Ian, 
> 
> I just discovered a strange behavior on linux 7.0.0rc3.
> 
> I run these commands on my x86 virtual machine:
> 
> bash-5.3# uname -m
> x86_64
> bash-5.3# perf -v
> perf version 6.18.13-200.fc43.x86_64
> bash-5.3# perf stat -- true
> 
>  Performance counter stats for 'true':
> 
>          1.108.929      task-clock                       #    0,437 CPUs utilized             
>                  0      context-switches                 #    0,000 /sec                      
>                  0      cpu-migrations                   #    0,000 /sec                      
>                 55      page-faults                      #   49,597 K/sec                     
>    <not supported>      cycles                                                                
> 
>        0,002536439 seconds time elapsed
> 
>        0,001363000 seconds user
>        0,001393000 seconds sys
> 
> bash-5.3#
> 
> This is the epected output, however when I use the perf version 7.0.0rc3:
> 
> bash-5.3# ./perf -v
> perf version 7.0.rc3.g1f318b96cc84
> bash-5.3# ./perf stat -- true
> Error:
> No supported events found.
> trace.args_alignment
> bash-5.3# 
> 
> Same happens on my s390 systems (LPAR and z/VM).
> Is this a known already?

I assume you are missing the patch below.  It has been picked to
perf-tools-next but not landed to mainline.

Author: Ian Rogers <irogers@google.com>
Date:   Fri Feb 6 16:49:56 2026 -0800

    perf metricgroup: Fix metricgroup__has_metric_or_groups

    Use metricgroup__for_each_metric rather than
    pmu_metrics_table__for_each_metric that combines the default metric
    table with, a potentially empty, CPUID table.

    Fixes: cee275edcdb1 ("perf metricgroup: Don't early exit if no CPUID table exists")
    Signed-off-by: Ian Rogers <irogers@google.com>
    Reviewed-by: Leo Yan <leo.yan@arm.com>
    Tested-by: Leo Yan <leo.yan@arm.com>
    Signed-off-by: Namhyung Kim <namhyung@kernel.org>

diff --git a/tools/perf/util/metricgroup.c b/tools/perf/util/metricgroup.c
index 46bf4dfeebc8..7e39d469111b 100644
--- a/tools/perf/util/metricgroup.c
+++ b/tools/perf/util/metricgroup.c
@@ -1605,9 +1605,9 @@ bool metricgroup__has_metric_or_groups(const char *pmu, const char *metric_or_gr
                .metric_or_groups = metric_or_groups,
        };

-       return pmu_metrics_table__for_each_metric(table,
-                                                 metricgroup__has_metric_or_groups_callback,
-                                                 &data)
+       return metricgroup__for_each_metric(table,
+                                           metricgroup__has_metric_or_groups_callback,
+                                           &data)
                ? true : false;
 }