Re: [PATCH v1] perf pmus: Sort/merge/aggregate PMUs like mrvl_ddr_pmu

From: Ian Rogers
Date: Mon Apr 08 2024 - 13:43:42 EST


On Thu, Mar 28, 2024 at 11:48 PM Ian Rogers <irogers@xxxxxxxxxx> wrote:
>
> The mrvl_ddr_pmu is uncore and has a hexadecimal address suffix while
> the previous PMU sorting/merging code assumes uncore PMU names start
> with uncore_ and have a decimal suffix. Because of the previous
> assumption it isn't possible to wildcard the mrvl_ddr_pmu.
>
> Modify pmu_name_len_no_suffix but also remove the suffix number out
> argument, this is because we don't know if a suffix number of say 10
> is in hexadecimal or decimal. As the only use of the suffix number is
> in comparisons, it is safe there to compare the values as hexadecimal.
>
> Add a set of PMUs tests for pmu_name_len_no_suffix and pmu_name_cmp.
>
> Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>

Ping. Here is a link to how marvell encode their PMU names that this
patch is hoping to fix:
https://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools-next.git/tree/drivers/perf/marvell_cn10k_ddr_pmu.c?h=perf-tools-next#n675

Thanks,
Ian

> ---
> tools/perf/tests/Build | 1 +
> tools/perf/tests/builtin-test.c | 1 +
> tools/perf/tests/pmus.c | 108 ++++++++++++++++++++++++++++++++
> tools/perf/tests/tests.h | 2 +
> tools/perf/util/pmu.c | 2 +-
> tools/perf/util/pmus.c | 51 ++++++++-------
> tools/perf/util/pmus.h | 7 ++-
> 7 files changed, 146 insertions(+), 26 deletions(-)
> create mode 100644 tools/perf/tests/pmus.c
>
> diff --git a/tools/perf/tests/Build b/tools/perf/tests/Build
> index c7f9d9676095..a7bab6e9300f 100644
> --- a/tools/perf/tests/Build
> +++ b/tools/perf/tests/Build
> @@ -14,6 +14,7 @@ perf-y += perf-record.o
> perf-y += evsel-roundtrip-name.o
> perf-$(CONFIG_LIBTRACEEVENT) += evsel-tp-sched.o
> perf-y += fdarray.o
> +perf-y += pmus.o
> perf-y += pmu.o
> perf-y += pmu-events.o
> perf-y += hists_common.o
> diff --git a/tools/perf/tests/builtin-test.c b/tools/perf/tests/builtin-test.c
> index d13ee7683d9d..c90f270a469a 100644
> --- a/tools/perf/tests/builtin-test.c
> +++ b/tools/perf/tests/builtin-test.c
> @@ -68,6 +68,7 @@ static struct test_suite *generic_tests[] = {
> &suite__parse_events,
> &suite__expr,
> &suite__PERF_RECORD,
> + &suite__pmus,
> &suite__pmu,
> &suite__pmu_events,
> &suite__dso_data,
> diff --git a/tools/perf/tests/pmus.c b/tools/perf/tests/pmus.c
> new file mode 100644
> index 000000000000..6279c925e689
> --- /dev/null
> +++ b/tools/perf/tests/pmus.c
> @@ -0,0 +1,108 @@
> +// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
> +#include "pmus.h"
> +#include "tests.h"
> +#include <string.h>
> +#include <linux/kernel.h>
> +
> +static const char * const uncore_chas[] = {
> + "uncore_cha_0",
> + "uncore_cha_1",
> + "uncore_cha_2",
> + "uncore_cha_3",
> + "uncore_cha_4",
> + "uncore_cha_5",
> + "uncore_cha_6",
> + "uncore_cha_7",
> + "uncore_cha_8",
> + "uncore_cha_9",
> + "uncore_cha_10",
> + "uncore_cha_11",
> + "uncore_cha_12",
> + "uncore_cha_13",
> + "uncore_cha_14",
> + "uncore_cha_15",
> + "uncore_cha_16",
> + "uncore_cha_17",
> + "uncore_cha_18",
> + "uncore_cha_19",
> + "uncore_cha_20",
> + "uncore_cha_21",
> + "uncore_cha_22",
> + "uncore_cha_23",
> + "uncore_cha_24",
> + "uncore_cha_25",
> + "uncore_cha_26",
> + "uncore_cha_27",
> + "uncore_cha_28",
> + "uncore_cha_29",
> + "uncore_cha_30",
> + "uncore_cha_31",
> +};
> +
> +static const char * const mrvl_ddrs[] = {
> + "mrvl_ddr_pmu_87e1b0000000",
> + "mrvl_ddr_pmu_87e1b1000000",
> + "mrvl_ddr_pmu_87e1b2000000",
> + "mrvl_ddr_pmu_87e1b3000000",
> + "mrvl_ddr_pmu_87e1b4000000",
> + "mrvl_ddr_pmu_87e1b5000000",
> + "mrvl_ddr_pmu_87e1b6000000",
> + "mrvl_ddr_pmu_87e1b7000000",
> + "mrvl_ddr_pmu_87e1b8000000",
> + "mrvl_ddr_pmu_87e1b9000000",
> + "mrvl_ddr_pmu_87e1ba000000",
> + "mrvl_ddr_pmu_87e1bb000000",
> + "mrvl_ddr_pmu_87e1bc000000",
> + "mrvl_ddr_pmu_87e1bd000000",
> + "mrvl_ddr_pmu_87e1be000000",
> + "mrvl_ddr_pmu_87e1bf000000",
> +};
> +
> +static int test__name_len(struct test_suite *test __maybe_unused, int subtest __maybe_unused)
> +{
> + TEST_ASSERT_EQUAL("cpu", pmu_name_len_no_suffix("cpu"), (int)strlen("cpu"));
> + TEST_ASSERT_EQUAL("i915", pmu_name_len_no_suffix("i915"), (int)strlen("i915"));
> + for (size_t i = 0; i < ARRAY_SIZE(uncore_chas); i++) {
> + TEST_ASSERT_EQUAL("Strips uncore_cha suffix",
> + pmu_name_len_no_suffix(uncore_chas[i]),
> + (int)strlen("uncore_cha"));
> + }
> + for (size_t i = 0; i < ARRAY_SIZE(mrvl_ddrs); i++) {
> + TEST_ASSERT_EQUAL("Strips mrvl_ddr_pmu suffix",
> + pmu_name_len_no_suffix(mrvl_ddrs[i]),
> + (int)strlen("mrvl_ddr_pmu"));
> + }
> + return TEST_OK;
> +}
> +
> +static int test__name_cmp(struct test_suite *test __maybe_unused, int subtest __maybe_unused)
> +{
> + TEST_ASSERT_EQUAL("cpu", pmu_name_cmp("cpu", "cpu"), 0);
> + TEST_ASSERT_EQUAL("i915", pmu_name_cmp("i915", "i915"), 0);
> + TEST_ASSERT_VAL("i915", pmu_name_cmp("cpu", "i915") < 0);
> + TEST_ASSERT_VAL("i915", pmu_name_cmp("i915", "cpu") > 0);
> + for (size_t i = 1; i < ARRAY_SIZE(uncore_chas); i++) {
> + TEST_ASSERT_VAL("uncore_cha suffixes ordered lt",
> + pmu_name_cmp(uncore_chas[i-1], uncore_chas[i]) < 0);
> + TEST_ASSERT_VAL("uncore_cha suffixes ordered gt",
> + pmu_name_cmp(uncore_chas[i], uncore_chas[i-1]) > 0);
> + }
> + for (size_t i = 1; i < ARRAY_SIZE(mrvl_ddrs); i++) {
> + TEST_ASSERT_VAL("mrvl_ddr_pmu suffixes ordered lt",
> + pmu_name_cmp(mrvl_ddrs[i-1], mrvl_ddrs[i]) < 0);
> + TEST_ASSERT_VAL("mrvl_ddr_pmu suffixes ordered gt",
> + pmu_name_cmp(mrvl_ddrs[i], mrvl_ddrs[i-1]) > 0);
> + }
> + return TEST_OK;
> +}
> +
> +static struct test_case tests__pmus[] = {
> + TEST_CASE("PMU name combining", name_len),
> + TEST_CASE("PMU name comparison", name_cmp),
> + { .name = NULL, }
> +};
> +
> +struct test_suite suite__pmus = {
> + .desc = "PMUs test",
> + .test_cases = tests__pmus,
> +};
> diff --git a/tools/perf/tests/tests.h b/tools/perf/tests/tests.h
> index 3aa7701ee0e9..03278f0f7698 100644
> --- a/tools/perf/tests/tests.h
> +++ b/tools/perf/tests/tests.h
> @@ -3,6 +3,7 @@
> #define TESTS_H
>
> #include <stdbool.h>
> +#include <debug.h>
>
> enum {
> TEST_OK = 0,
> @@ -81,6 +82,7 @@ DECLARE_SUITE(PERF_RECORD);
> DECLARE_SUITE(perf_evsel__roundtrip_name_test);
> DECLARE_SUITE(perf_evsel__tp_sched_test);
> DECLARE_SUITE(syscall_openat_tp_fields);
> +DECLARE_SUITE(pmus);
> DECLARE_SUITE(pmu);
> DECLARE_SUITE(pmu_events);
> DECLARE_SUITE(attr);
> diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
> index f39cbbc1a7ec..b0cca5841f90 100644
> --- a/tools/perf/util/pmu.c
> +++ b/tools/perf/util/pmu.c
> @@ -1657,7 +1657,7 @@ static char *format_alias(char *buf, int len, const struct perf_pmu *pmu,
> {
> struct parse_events_term *term;
> int pmu_name_len = skip_duplicate_pmus
> - ? pmu_name_len_no_suffix(pmu->name, /*num=*/NULL)
> + ? pmu_name_len_no_suffix(pmu->name)
> : (int)strlen(pmu->name);
> int used = snprintf(buf, len, "%.*s/%s", pmu_name_len, pmu->name, alias->name);
>
> diff --git a/tools/perf/util/pmus.c b/tools/perf/util/pmus.c
> index 16505071d362..b4ddcd0ade26 100644
> --- a/tools/perf/util/pmus.c
> +++ b/tools/perf/util/pmus.c
> @@ -39,31 +39,44 @@ static bool read_sysfs_all_pmus;
>
> static void pmu_read_sysfs(bool core_only);
>
> -int pmu_name_len_no_suffix(const char *str, unsigned long *num)
> +int pmu_name_len_no_suffix(const char *str)
> {
> int orig_len, len;
>
> orig_len = len = strlen(str);
>
> - /* Non-uncore PMUs have their full length, for example, i915. */
> - if (!strstarts(str, "uncore_"))
> - return len;
> -
> /*
> * Count trailing digits and '_', if '_{num}' suffix isn't present use
> * the full length.
> */
> - while (len > 0 && isdigit(str[len - 1]))
> + while (len > 0 && isxdigit(str[len - 1]))
> len--;
>
> - if (len > 0 && len != orig_len && str[len - 1] == '_') {
> - if (num)
> - *num = strtoul(&str[len], NULL, 10);
> + if (len > 0 && len != orig_len && str[len - 1] == '_')
> return len - 1;
> - }
> +
> return orig_len;
> }
>
> +int pmu_name_cmp(const char *lhs_pmu_name, const char *rhs_pmu_name)
> +{
> + unsigned long lhs_num = 0, rhs_num = 0;
> + int lhs_pmu_name_len = pmu_name_len_no_suffix(lhs_pmu_name);
> + int rhs_pmu_name_len = pmu_name_len_no_suffix(rhs_pmu_name);
> + int ret = strncmp(lhs_pmu_name, rhs_pmu_name,
> + lhs_pmu_name_len < rhs_pmu_name_len ? lhs_pmu_name_len : rhs_pmu_name_len);
> +
> + if (lhs_pmu_name_len != rhs_pmu_name_len || ret != 0 || lhs_pmu_name_len == 0)
> + return ret;
> +
> + if (lhs_pmu_name_len + 1 < (int)strlen(lhs_pmu_name))
> + lhs_num = strtoul(&lhs_pmu_name[lhs_pmu_name_len + 1], NULL, 16);
> + if (rhs_pmu_name_len + 1 < (int)strlen(rhs_pmu_name))
> + rhs_num = strtoul(&rhs_pmu_name[rhs_pmu_name_len + 1], NULL, 16);
> +
> + return lhs_num < rhs_num ? -1 : (lhs_num > rhs_num ? 1 : 0);
> +}
> +
> void perf_pmus__destroy(void)
> {
> struct perf_pmu *pmu, *tmp;
> @@ -164,20 +177,10 @@ static struct perf_pmu *perf_pmu__find2(int dirfd, const char *name)
> static int pmus_cmp(void *priv __maybe_unused,
> const struct list_head *lhs, const struct list_head *rhs)
> {
> - unsigned long lhs_num = 0, rhs_num = 0;
> struct perf_pmu *lhs_pmu = container_of(lhs, struct perf_pmu, list);
> struct perf_pmu *rhs_pmu = container_of(rhs, struct perf_pmu, list);
> - const char *lhs_pmu_name = lhs_pmu->name ?: "";
> - const char *rhs_pmu_name = rhs_pmu->name ?: "";
> - int lhs_pmu_name_len = pmu_name_len_no_suffix(lhs_pmu_name, &lhs_num);
> - int rhs_pmu_name_len = pmu_name_len_no_suffix(rhs_pmu_name, &rhs_num);
> - int ret = strncmp(lhs_pmu_name, rhs_pmu_name,
> - lhs_pmu_name_len < rhs_pmu_name_len ? lhs_pmu_name_len : rhs_pmu_name_len);
>
> - if (lhs_pmu_name_len != rhs_pmu_name_len || ret != 0 || lhs_pmu_name_len == 0)
> - return ret;
> -
> - return lhs_num < rhs_num ? -1 : (lhs_num > rhs_num ? 1 : 0);
> + return pmu_name_cmp(lhs_pmu->name ?: "", rhs_pmu->name ?: "");
> }
>
> /* Add all pmus in sysfs to pmu list: */
> @@ -297,11 +300,11 @@ static struct perf_pmu *perf_pmus__scan_skip_duplicates(struct perf_pmu *pmu)
> pmu_read_sysfs(/*core_only=*/false);
> pmu = list_prepare_entry(pmu, &core_pmus, list);
> } else
> - last_pmu_name_len = pmu_name_len_no_suffix(pmu->name ?: "", NULL);
> + last_pmu_name_len = pmu_name_len_no_suffix(pmu->name ?: "");
>
> if (use_core_pmus) {
> list_for_each_entry_continue(pmu, &core_pmus, list) {
> - int pmu_name_len = pmu_name_len_no_suffix(pmu->name ?: "", /*num=*/NULL);
> + int pmu_name_len = pmu_name_len_no_suffix(pmu->name ?: "");
>
> if (last_pmu_name_len == pmu_name_len &&
> !strncmp(last_pmu_name, pmu->name ?: "", pmu_name_len))
> @@ -313,7 +316,7 @@ static struct perf_pmu *perf_pmus__scan_skip_duplicates(struct perf_pmu *pmu)
> pmu = list_prepare_entry(pmu, &other_pmus, list);
> }
> list_for_each_entry_continue(pmu, &other_pmus, list) {
> - int pmu_name_len = pmu_name_len_no_suffix(pmu->name ?: "", /*num=*/NULL);
> + int pmu_name_len = pmu_name_len_no_suffix(pmu->name ?: "");
>
> if (last_pmu_name_len == pmu_name_len &&
> !strncmp(last_pmu_name, pmu->name ?: "", pmu_name_len))
> diff --git a/tools/perf/util/pmus.h b/tools/perf/util/pmus.h
> index 94d2a08d894b..624c2d53fc30 100644
> --- a/tools/perf/util/pmus.h
> +++ b/tools/perf/util/pmus.h
> @@ -2,10 +2,15 @@
> #ifndef __PMUS_H
> #define __PMUS_H
>
> +#include <stdbool.h>
> +#include <linux/list.h>
> +
> struct perf_pmu;
> struct print_callbacks;
>
> -int pmu_name_len_no_suffix(const char *str, unsigned long *num);
> +int pmu_name_len_no_suffix(const char *str);
> +/* Exposed for testing only. */
> +int pmu_name_cmp(const char *lhs_pmu_name, const char *rhs_pmu_name);
>
> void perf_pmus__destroy(void);
>
> --
> 2.44.0.478.gd926399ef9-goog
>