Re: [PATCH v3 bpf-next 09/10] bpftool: Add perf event names

[Yafang Shao <laoar.shao@gmail.com>]

On Tue, Jun 13, 2023 at 9:42 PM Quentin Monnet <quentin@isovalent.com> wrote:
>
> 2023-06-12 15:16 UTC+0000 ~ Yafang Shao <laoar.shao@gmail.com>
> > Add new functions and macros to get perf event names. These names are
> > copied from tool/perf/util/{parse-events,evsel}.c, so that in the future we
> > will have a good chance to use the same code.
> >
> > Suggested-by: Jiri Olsa <olsajiri@gmail.com>
> > Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
> > ---
> >  tools/bpf/bpftool/perf.c | 107 +++++++++++++++++++++++++++++++++++++++++++++++
> >  tools/bpf/bpftool/perf.h |  11 +++++
>
> Although the names are deceiving, I think these should all be moved to
> link.c and link.h, where we'll actually use them, or to some other file
> with a new name. File perf.c is for implementing "bpftool perf ...".

Got it. Will move them into link.c.

>
> >  2 files changed, 118 insertions(+)
> >  create mode 100644 tools/bpf/bpftool/perf.h
> >
> > diff --git a/tools/bpf/bpftool/perf.c b/tools/bpf/bpftool/perf.c
> > index 9174344..fbdf88c 100644
> > --- a/tools/bpf/bpftool/perf.c
> > +++ b/tools/bpf/bpftool/perf.c
> > @@ -18,6 +18,113 @@
> >  #include <bpf/bpf.h>
> >
> >  #include "main.h"
> > +#include "perf.h"
> > +
> > +static const char *perf_type_name[PERF_TYPE_MAX] = {
> > +     [PERF_TYPE_HARDWARE]                    = "hardware",
> > +     [PERF_TYPE_SOFTWARE]                    = "software",
> > +     [PERF_TYPE_TRACEPOINT]                  = "tracepoint",
> > +     [PERF_TYPE_HW_CACHE]                    = "hw-cache",
> > +     [PERF_TYPE_RAW]                         = "raw",
> > +     [PERF_TYPE_BREAKPOINT]                  = "breakpoint",
> > +};
> > +
> > +const char *event_symbols_hw[PERF_COUNT_HW_MAX] = {
> > +     [PERF_COUNT_HW_CPU_CYCLES]              = "cpu-cycles",
> > +     [PERF_COUNT_HW_INSTRUCTIONS]            = "instructions",
> > +     [PERF_COUNT_HW_CACHE_REFERENCES]        = "cache-references",
> > +     [PERF_COUNT_HW_CACHE_MISSES]            = "cache-misses",
> > +     [PERF_COUNT_HW_BRANCH_INSTRUCTIONS]     = "branch-instructions",
> > +     [PERF_COUNT_HW_BRANCH_MISSES]           = "branch-misses",
> > +     [PERF_COUNT_HW_BUS_CYCLES]              = "bus-cycles",
> > +     [PERF_COUNT_HW_STALLED_CYCLES_FRONTEND] = "stalled-cycles-frontend",
> > +     [PERF_COUNT_HW_STALLED_CYCLES_BACKEND]  = "stalled-cycles-backend",
> > +     [PERF_COUNT_HW_REF_CPU_CYCLES]          = "ref-cycles",
> > +};
> > +
> > +const char *event_symbols_sw[PERF_COUNT_SW_MAX] = {
> > +     [PERF_COUNT_SW_CPU_CLOCK]               = "cpu-clock",
> > +     [PERF_COUNT_SW_TASK_CLOCK]              = "task-clock",
> > +     [PERF_COUNT_SW_PAGE_FAULTS]             = "page-faults",
> > +     [PERF_COUNT_SW_CONTEXT_SWITCHES]        = "context-switches",
> > +     [PERF_COUNT_SW_CPU_MIGRATIONS]          = "cpu-migrations",
> > +     [PERF_COUNT_SW_PAGE_FAULTS_MIN]         = "minor-faults",
> > +     [PERF_COUNT_SW_PAGE_FAULTS_MAJ]         = "major-faults",
> > +     [PERF_COUNT_SW_ALIGNMENT_FAULTS]        = "alignment-faults",
> > +     [PERF_COUNT_SW_EMULATION_FAULTS]        = "emulation-faults",
> > +     [PERF_COUNT_SW_DUMMY]                   = "dummy",
> > +     [PERF_COUNT_SW_BPF_OUTPUT]              = "bpf-output",
> > +     [PERF_COUNT_SW_CGROUP_SWITCHES]         = "cgroup-switches",
> > +};
> > +
> > +const char *evsel__hw_cache[PERF_COUNT_HW_CACHE_MAX] = {
> > +     [PERF_COUNT_HW_CACHE_L1D]               = "L1-dcache",
> > +     [PERF_COUNT_HW_CACHE_L1I]               = "L1-icache",
> > +     [PERF_COUNT_HW_CACHE_LL]                = "LLC",
> > +     [PERF_COUNT_HW_CACHE_DTLB]              = "dTLB",
> > +     [PERF_COUNT_HW_CACHE_ITLB]              = "iTLB",
> > +     [PERF_COUNT_HW_CACHE_BPU]               = "branch",
> > +     [PERF_COUNT_HW_CACHE_NODE]              = "node",
> > +};
> > +
> > +const char *evsel__hw_cache_op[PERF_COUNT_HW_CACHE_OP_MAX] = {
> > +     [PERF_COUNT_HW_CACHE_OP_READ]           = "load",
> > +     [PERF_COUNT_HW_CACHE_OP_WRITE]          = "store",
> > +     [PERF_COUNT_HW_CACHE_OP_PREFETCH]       = "prefetch",
> > +};
> > +
> > +const char *evsel__hw_cache_result[PERF_COUNT_HW_CACHE_RESULT_MAX] = {
> > +     [PERF_COUNT_HW_CACHE_RESULT_ACCESS]     = "refs",
> > +     [PERF_COUNT_HW_CACHE_RESULT_MISS]       = "misses",
> > +};
> > +
> > +const char *perf_type_str(enum perf_type_id t)
> > +{
> > +     if (t < 0 || t >= ARRAY_SIZE(perf_type_name))
> > +             return NULL;
> > +
> > +     return perf_type_name[t];
> > +}
> > +
> > +const char *perf_hw_str(enum perf_hw_id t)
> > +{
> > +     if (t < 0 || t >= ARRAY_SIZE(event_symbols_hw))
> > +             return NULL;
> > +
> > +     return event_symbols_hw[t];
> > +}
> > +
> > +const char *perf_hw_cache_str(enum perf_hw_cache_id t)
> > +{
> > +     if (t < 0 || t >= ARRAY_SIZE(evsel__hw_cache))
> > +             return NULL;
> > +
> > +     return evsel__hw_cache[t];
> > +}
> > +
> > +const char *perf_hw_cache_op_str(enum perf_hw_cache_op_id t)
> > +{
> > +     if (t < 0 || t >= ARRAY_SIZE(evsel__hw_cache_op))
> > +             return NULL;
> > +
> > +     return evsel__hw_cache_op[t];
> > +}
> > +
> > +const char *perf_hw_cache_op_result_str(enum perf_hw_cache_op_result_id t)
> > +{
> > +     if (t < 0 || t >= ARRAY_SIZE(evsel__hw_cache_result))
> > +             return NULL;
> > +
> > +     return evsel__hw_cache_result[t];
> > +}
> > +
> > +const char *perf_sw_str(enum perf_sw_ids t)
> > +{
> > +     if (t < 0 || t >= ARRAY_SIZE(event_symbols_sw))
> > +             return NULL;
> > +
> > +     return event_symbols_sw[t];
> > +}
> >
> >  /* 0: undecided, 1: supported, 2: not supported */
> >  static int perf_query_supported;
> > diff --git a/tools/bpf/bpftool/perf.h b/tools/bpf/bpftool/perf.h
> > new file mode 100644
> > index 0000000..3fd7e42
> > --- /dev/null
> > +++ b/tools/bpf/bpftool/perf.h
> > @@ -0,0 +1,11 @@
> > +/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) */
> > +/* Copyright (C) 2023 Yafang Shao <laoar.shao@gmail.com> */
> > +
> > +#include <linux/perf_event.h>
> > +
> > +const char *perf_type_str(enum perf_type_id t);
> > +const char *perf_hw_str(enum perf_hw_id t);
> > +const char *perf_hw_cache_str(enum perf_hw_cache_id t);
> > +const char *perf_hw_cache_op_str(enum perf_hw_cache_op_id t);
> > +const char *perf_hw_cache_op_result_str(enum perf_hw_cache_op_result_id t);
> > +const char *perf_sw_str(enum perf_sw_ids t);
>
> I'm not sure we need all these API functions if we keep the arrays in
> bpftool. I'd probably have just a generic one and pass it the name of
> the relevant array in argument. Although I've got no objection with the
> current form if it helps unifying the code with perf in the future.
>

Sure, I will use a generic one instead.

-- 
Regards
Yafang