perf pmu-events x86: Use CPU_CLK_UNHALTED.THREAD in Kernel_Utilization metric
The kernel utilization metric does multiplexing currently and is somewhat unreliable. The problem is that it uses two instances of the fixed counter, and the kernel has to multipleplex which causes errors. So should use CPU_CLK_UNHALTED.THREAD instead. Before: # perf stat -M Kernel_Utilization -- sleep 1 Performance counter stats for 'sleep 1': 1,419,425 cpu_clk_unhalted.ref_tsc:k <not counted> cpu_clk_unhalted.ref_tsc (0.00%) After: # perf stat -M Kernel_Utilization -- sleep 1 Performance counter stats for 'sleep 1': 746,688 cpu_clk_unhalted.thread:k # 0.7 Kernel_Utilization 1,088,348 cpu_clk_unhalted.thread Signed-off-by: NJin Yao <yao.jin@linux.intel.com> Reviewed-by: NAndi Kleen <ak@linux.intel.com> Reviewed-by: NKan Liang <kan.liang@linux.intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jin Yao <yao.jin@intel.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lore.kernel.org/lkml/20200309013125.7559-1-yao.jin@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
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