在哪里可以找到 perf 事件文档

Question

在问题cpu cache performance. store misses vs load misses中，没有回答在哪里可以找到perf list

列出的事件的文档

我无法通过 man perf 和 perf help list、

找到它

看了Intel@64和AMD64的Event文档，事件格式如下 Last Level Cache References — Event select 2EH, Umask 4FH 那么它在哪里呢？

编辑：为了清楚起见，我想通过perf list

查找事件列表的文档

Answer 1

预定义 perf 事件列表，如 branches cycles LLC-load-misses 由 Linux 内核中的 perf 子系统的源代码记录。该列表部分映射到不同 CPU 模型和微体系结构的各种硬件事件。使用 ocperf.py (and toplev.py) from andikleen's pmu-tools (if your CPU is Intel) with event names from Intel documentations (ocperf is not official, but it is written by Intel employee and uses official lists from https://download.01.org/perfmon/ https://download.01.org/perfmon/readme.txt "This package contains performance monitoring event lists for Intel processors")

会更有用

对于 x86 和 x86_64 perf 这些（古老的）predefined/generic 名称映射到 arch/x86/events directory, for example for all Intel Core microarchitecures check arch/x86/events/intel/core.c and search for microarchitecture by its code name (Core, Core2, NHM=Nehalem, WSM=Westmere, SNB=SandyBridge, IVB=IvyBridge, HSW=HaSWell, BDW=BroaDWell,SKL=SKyLake, SLM=SiLverMont and other from lists and amd). For Skylake there is structure at line 394 of intel/core.c of 4.15.8，我们看到 PREFETCH 计数器未映射到所有缓存（ "not supported")

 static __initconst const u64 skl_hw_cache_event_ids

 [ C(L1D ) ] = {
    [ C(OP_READ) ] = {
        [ C(RESULT_ACCESS) ] = 0x81d0,  /* MEM_INST_RETIRED.ALL_LOADS */
        [ C(RESULT_MISS)   ] = 0x151,   /* L1D.REPLACEMENT */
    },
    [ C(OP_WRITE) ] = {
        [ C(RESULT_ACCESS) ] = 0x82d0,  /* MEM_INST_RETIRED.ALL_STORES */
        [ C(RESULT_MISS)   ] = 0x0,

...
 [ C(LL  ) ] = {
    [ C(OP_READ) ] = {
        [ C(RESULT_ACCESS) ] = 0x1b7,   /* OFFCORE_RESPONSE */
        [ C(RESULT_MISS)   ] = 0x1b7,   /* OFFCORE_RESPONSE */
    },
    [ C(OP_WRITE) ] = {
        [ C(RESULT_ACCESS) ] = 0x1b7,   /* OFFCORE_RESPONSE */
        [ C(RESULT_MISS)   ] = 0x1b7,   /* OFFCORE_RESPONSE */
    },

和额外的结构来为 OFFCORE_RESPONSE:

等事件定义额外的 flags/masks

static __initconst const u64 skl_hw_cache_extra_regs 
 [ C(LL  ) ] = {
    [ C(OP_READ) ] = {
        [ C(RESULT_ACCESS) ] = SKL_DEMAND_READ|
                       SKL_LLC_ACCESS|SKL_ANY_SNOOP,
        [ C(RESULT_MISS)   ] = SKL_DEMAND_READ|
                       SKL_L3_MISS|SKL_ANY_SNOOP|
                       SKL_SUPPLIER_NONE,
    },
    [ C(OP_WRITE) ] = {
        [ C(RESULT_ACCESS) ] = SKL_DEMAND_WRITE|
                       SKL_LLC_ACCESS|SKL_ANY_SNOOP,
        [ C(RESULT_MISS)   ] = SKL_DEMAND_WRITE|
                       SKL_L3_MISS|SKL_ANY_SNOOP|
                       SKL_SUPPLIER_NONE,
 [ C(NODE) ] = {
    [ C(OP_READ) ] = {
        [ C(RESULT_ACCESS) ] = SKL_DEMAND_READ|
                       SKL_L3_MISS_LOCAL_DRAM|SKL_SNOOP_DRAM,
        [ C(RESULT_MISS)   ] = SKL_DEMAND_READ|
                       SKL_L3_MISS_REMOTE|SKL_SNOOP_DRAM,
    },
    [ C(OP_WRITE) ] = {
        [ C(RESULT_ACCESS) ] = SKL_DEMAND_WRITE|
                       SKL_L3_MISS_LOCAL_DRAM|SKL_SNOOP_DRAM,
        [ C(RESULT_MISS)   ] = SKL_DEMAND_WRITE|
                       SKL_L3_MISS_REMOTE|SKL_SNOOP_DRAM,

在哪里可以找到 perf 事件文档

Where to find perf event document

kernel

document

manual

perf