| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <CAP-5=fVeYM7RJ0wW7S+9F+UnWW9pRphJMQhmBxT=V7zfmQF3cA@mail.gmail.com>
Date: Thu, 18 Sep 2025 08:33:30 -0700
From: Ian Rogers <irogers@...gle.com>
To: Namhyung Kim <namhyung@...nel.org>
Cc: Arnaldo Carvalho de Melo <acme@...nel.org>, Kan Liang <kan.liang@...ux.intel.com>,
Jiri Olsa <jolsa@...nel.org>, Adrian Hunter <adrian.hunter@...el.com>,
Peter Zijlstra <peterz@...radead.org>, Ingo Molnar <mingo@...nel.org>,
LKML <linux-kernel@...r.kernel.org>, linux-perf-users@...r.kernel.org
Subject: Re: [RFC/PATCH 2/2] perf check: Add 'pmu' subcommand
On Wed, Sep 17, 2025 at 11:39 PM Namhyung Kim <namhyung@...nel.org> wrote:
>
> The 'perf check pmu' command will show information about PMUs in the
> system like below:
>
> $ perf check pmu | head
> cpu_atom: type = 10
> core PMU: cpus = 16-27
> caps: branches = 32
> caps: max_precise = 3
> caps: pmu_name = alderlake_hybrid
> cpu_core: type = 4
> core PMU: cpus = 0-15
> caps: branches = 32
> caps: max_precise = 3
> caps: pmu_name = alderlake_hybrid
>
> The -q option will make it print the name and type of PMUs only. It
> also takes arguments to show matching PMUs only.
>
> $ perf check pmu -q uncore
> uncore_arb_0: type = 27
> uncore_arb_1: type = 28
> uncore_cbox_0: type = 15
> uncore_cbox_1: type = 16
> uncore_cbox_2: type = 17
> uncore_cbox_3: type = 18
> uncore_cbox_4: type = 19
> uncore_cbox_5: type = 20
> uncore_cbox_6: type = 21
> uncore_cbox_7: type = 22
> uncore_cbox_8: type = 23
> uncore_cbox_9: type = 24
> uncore_cbox_10: type = 25
> uncore_cbox_11: type = 26
> uncore_clock: type = 29
> uncore_imc_free_running_0: type = 32
> uncore_imc_free_running_1: type = 33
> uncore_imc_0: type = 30
> uncore_imc_1: type = 31
>
> Signed-off-by: Namhyung Kim <namhyung@...nel.org>
> ---
> tools/perf/Documentation/perf-check.txt | 12 +++++
> tools/perf/builtin-check.c | 60 ++++++++++++++++++++++++-
> 2 files changed, 71 insertions(+), 1 deletion(-)
>
> diff --git a/tools/perf/Documentation/perf-check.txt b/tools/perf/Documentation/perf-check.txt
> index 34dccc29d90d2fdf..2fa007698c0f0814 100644
> --- a/tools/perf/Documentation/perf-check.txt
> +++ b/tools/perf/Documentation/perf-check.txt
> @@ -11,6 +11,7 @@ SYNOPSIS
> 'perf check' [<options>]
> 'perf check' {feature <feature_list>} [<options>]
> 'perf check' {system <setting_list>} [<options>]
> +'perf check' {pmu <name_list>} [<options>]
>
> DESCRIPTION
> -----------
> @@ -26,6 +27,9 @@ is built-in, otherwise returns with exit status 1.
> If the subcommand 'system' is used, then system settins are printed on
> the standard output with explanation.
>
> +If the subcommand 'pmu' is used, then available PMU information is printed
> +on the standard output with explanation.
> +
> SUBCOMMANDS
> -----------
>
> @@ -88,6 +92,14 @@ SUBCOMMANDS
> nmi_watchdog
> kptr_restrict
>
> +pmu::
> +
> + Print PMU information available in the system.
> +
> + Example Usage:
> + perf check pmu
> + perf check pmu <name>
> +
>
> OPTIONS
> -------
> diff --git a/tools/perf/builtin-check.c b/tools/perf/builtin-check.c
> index 1c7c6bb5da5ccbf2..f3d034a94b1227c7 100644
> --- a/tools/perf/builtin-check.c
> +++ b/tools/perf/builtin-check.c
> @@ -3,6 +3,8 @@
> #include "color.h"
> #include "util/debug.h"
> #include "util/header.h"
> +#include "util/pmu.h"
> +#include "util/pmus.h"
> #include <api/fs/fs.h>
> #include <tools/config.h>
> #include <stdbool.h>
> @@ -10,13 +12,14 @@
> #include <string.h>
> #include <subcmd/parse-options.h>
>
> -static const char * const check_subcommands[] = { "feature", "system", NULL };
> +static const char * const check_subcommands[] = { "feature", "system", "pmu", NULL };
> static struct option check_options[] = {
> OPT_BOOLEAN('q', "quiet", &quiet, "do not show any warnings or messages"),
> OPT_END()
> };
> static struct option check_feature_options[] = { OPT_PARENT(check_options) };
> static struct option check_system_options[] = { OPT_PARENT(check_options) };
> +static struct option check_pmu_options[] = { OPT_PARENT(check_options) };
>
> static const char *check_usage[] = { NULL, NULL };
> static const char *check_feature_usage[] = {
> @@ -27,6 +30,10 @@ static const char *check_system_usage[] = {
> "perf check system",
> NULL
> };
> +static const char *check_pmu_usage[] = {
> + "perf check pmu",
> + NULL
> +};
>
> #define FEATURE_STATUS(name_, macro_) { \
> .name = name_, \
> @@ -278,6 +285,55 @@ static int subcommand_system(int argc, const char **argv)
> return 0;
> }
>
> +/**
> + * Usage: 'perf check pmu <names>'
> + *
> + * Show PMU information.
> + */
> +static int subcommand_pmu(int argc, const char **argv)
> +{
> + struct perf_pmu *pmu = NULL;
> + struct perf_pmu_caps *caps;
> +
> + argc = parse_options(argc, argv, check_pmu_options, check_pmu_usage, 0);
> +
> + while ((pmu = perf_pmus__scan(pmu)) != NULL) {
> + if (argc) {
> + bool found = false;
> +
> + /* only show entries match to command line arguments */
> + for (int k = 0; k < argc; k++) {
> + if (strstr(pmu->name, argv[k])) {
To avoid divergence from parse-events it may be better to use
perf_pmu__wildcard_match? There is also
perf_pmus__scan_matching_wildcard.
> + found = true;
> + break;
> + }
> + }
> + if (!found)
> + continue;
> + }
> +
> + printf("%s: type = %u\n", pmu->name, pmu->type);
> + if (quiet)
> + continue;
> +
> + if (pmu->is_core || pmu->is_uncore) {
> + printf(" %score PMU", pmu->is_uncore ? "un" : "");
> + if (!perf_cpu_map__is_empty(pmu->cpus)) {
> + printf(": %s = ", pmu->is_core ? "cpus" : "cpumask");
The cpus file is only generally present on hybrid systems. I don't
think this needs to be core/uncore dependent - the only thing I've
ever seen fail that test are some ARM uncore PMUs. I'd always dump
this as cpumask, when !core and !uncore then the default all online
CPUs cpumask is important information as that probably isn't the
cpumask you want with an uncore PMU.
> + cpu_map__fprintf(pmu->cpus, stdout);
> + } else {
> + printf("\n");
> + }
> + }
> +
> + perf_pmu__caps_parse(pmu);
> + list_for_each_entry(caps, &pmu->caps, list) {
> + printf(" caps: %s = %s\n", caps->name, caps->value);
> + }
> + }
> + return 0;
If not found return an error?
Thanks,
Ian
> +}
> +
> int cmd_check(int argc, const char **argv)
> {
> argc = parse_options_subcommand(argc, argv, check_options,
> @@ -290,6 +346,8 @@ int cmd_check(int argc, const char **argv)
> return subcommand_feature(argc, argv);
> if (strcmp(argv[0], "system") == 0)
> return subcommand_system(argc, argv);
> + if (strcmp(argv[0], "pmu") == 0)
> + return subcommand_pmu(argc, argv);
>
> /* If no subcommand matched above, print usage help */
> pr_err("Unknown subcommand: %s\n", argv[0]);
> --
> 2.51.0
>
Powered by blists - more mailing lists