Linux Perf PMU 事件在 Sapphire Rapids 中没有 UNCORE_CXL 事件

Question

我在 Xeon 6438 上使用 Linux 6.5.0，我注意到

tools/perf/pmu-events/arch/x86/sapphirerapids/

下有一个 uncore_cxl.json 文件，它定义了很多 cxl 相关事件，但是我通过

perf list

找不到它们，那么如何访问这些事件？

顺便说一句，

tools/perf/pmu-events/arch/x86/sapphirerapids/uncore_*.json

中列出的事件（除了cxl）都可以在perf中看到。

perf list | grep cxl

：

  unc_cha_tor_inserts.ia_hit_cxl_acc
  unc_cha_tor_inserts.ia_hit_cxl_acc_local
  unc_cha_tor_inserts.ia_miss_crdmorph_cxl_acc
  unc_cha_tor_inserts.ia_miss_cxl_acc
  unc_cha_tor_inserts.ia_miss_cxl_acc_local
  unc_cha_tor_inserts.ia_miss_drd_cxl_acc
  unc_cha_tor_inserts.ia_miss_drd_cxl_acc_local
  unc_cha_tor_inserts.ia_miss_drd_opt_cxl_acc_local
  unc_cha_tor_inserts.ia_miss_drd_opt_pref_cxl_acc_local
  unc_cha_tor_inserts.ia_miss_drd_pref_cxl_acc
  unc_cha_tor_inserts.ia_miss_drd_pref_cxl_acc_local
  unc_cha_tor_inserts.ia_miss_drdmorph_cxl_acc
  unc_cha_tor_inserts.ia_miss_llcprefcode_cxl_acc
  unc_cha_tor_inserts.ia_miss_llcprefdata_cxl_acc
  unc_cha_tor_inserts.ia_miss_llcprefdata_cxl_acc_local
  unc_cha_tor_inserts.ia_miss_llcprefrfo_cxl_acc
  unc_cha_tor_inserts.ia_miss_llcprefrfo_cxl_acc_local
  unc_cha_tor_inserts.ia_miss_rfo_cxl_acc
  unc_cha_tor_inserts.ia_miss_rfo_cxl_acc_local
  unc_cha_tor_inserts.ia_miss_rfo_pref_cxl_acc
  unc_cha_tor_inserts.ia_miss_rfo_pref_cxl_acc_local
  unc_cha_tor_inserts.ia_miss_rfomorph_cxl_acc
***********

tools/perf/pmu-events/arch/x86/sapphirerapids/uncore_cxl.json

：

[
    {
        "BriefDescription": "Counts the number of lfclk ticks",
        "Counter": "0,1,2,3,4,5,6,7",
        "EventCode": "0x01",
        "EventName": "UNC_CXLCM_CLOCKTICKS",
        "PerPkg": "1",
        "UMask": "0x2",
        "Unit": "CXLCM"
    },
    {
        "BriefDescription": "Number of Allocation to Mem Rxx AGF 0",
        "Counter": "4,5,6,7",
        "EventCode": "0x43",
        "EventName": "UNC_CXLCM_RxC_AGF_INSERTS.CACHE_DATA",
        "Experimental": "1",
        "PerPkg": "1",
        "UMask": "0x8",
        "Unit": "CXLCM"
    },
    {
        "BriefDescription": "Number of Allocation to Cache Req AGF0",
        "Counter": "4,5,6,7",
        "EventCode": "0x43",
        "EventName": "UNC_CXLCM_RxC_AGF_INSERTS.CACHE_REQ0",
        "Experimental": "1",
        "PerPkg": "1",
        "UMask": "0x1",
        "Unit": "CXLCM"
    },
    {
        "BriefDescription": "Number of Allocation to Cache Rsp AGF",
        "Counter": "4,5,6,7",
        "EventCode": "0x43",
        "EventName": "UNC_CXLCM_RxC_AGF_INSERTS.CACHE_REQ1",
        "Experimental": "1",
        "PerPkg": "1",
        "UMask": "0x2",
        "Unit": "CXLCM"
    },

Answer 1

这个问题你解决了吗？我也有同样的疑问。