[PATCH v4 2/5] perf hwmon_pmu: Add a tool PMU exposing events from hwmon in sysfs

From: Ian Rogers
Date: Tue Oct 15 2024 - 17:07:31 EST


Add a tool PMU for hwmon events but don't enable.

The hwmon sysfs ABI is defined in
Documentation/hwmon/sysfs-interface.rst. Create a PMU that reads the
hwmon input and can be used in `perf stat` and metrics much as an
uncore PMU can.

For example, when enabled by a later patch, the following shows
reading the CPU temperature and 2 fan speeds alongside the uncore
frequency:
```
$ perf stat -e temp_cpu,fan1,hwmon_thinkpad/fan2/,tool/num_cpus_online/ -M UNCORE_FREQ -I 1000
1.001153138 52.00 'C temp_cpu
1.001153138 2,588 rpm fan1
1.001153138 2,482 rpm hwmon_thinkpad/fan2/
1.001153138 8 tool/num_cpus_online/
1.001153138 1,077,101,397 UNC_CLOCK.SOCKET # 1.08 UNCORE_FREQ
1.001153138 1,012,773,595 duration_time
...
```

The PMUs are named from /sys/class/hwmon/hwmon<num>/name and have an
alias of hwmon<num>.

Hwmon data is presented in multiple <type><number>_<item> files. The
<type><number> is used to identify the event as is the <type> followed
by the contents of the <type>_label file if it exists. The
<type><number>_input file gives the data read by perf.

When enabled by a later patch, in `perf list` the other hwmon <item>
files are used to give a richer description, for example:
```
hwmon:
temp1
[Temperature in unit acpitz named temp1. Unit: hwmon_acpitz]
in0
[Voltage in unit bat0 named in0. Unit: hwmon_bat0]
temp_core_0 OR temp2
[Temperature in unit coretemp named Core 0. crit=100'C,max=100'C crit_alarm=0'C. Unit:
hwmon_coretemp]
temp_core_1 OR temp3
[Temperature in unit coretemp named Core 1. crit=100'C,max=100'C crit_alarm=0'C. Unit:
hwmon_coretemp]
...
temp_package_id_0 OR temp1
[Temperature in unit coretemp named Package id 0. crit=100'C,max=100'C crit_alarm=0'C.
Unit: hwmon_coretemp]
temp1
[Temperature in unit iwlwifi_1 named temp1. Unit: hwmon_iwlwifi_1]
temp_composite OR temp1
[Temperature in unit nvme named Composite. alarm=0'C,crit=86.85'C,max=75.85'C,
min=-273.15'C. Unit: hwmon_nvme]
temp_sensor_1 OR temp2
[Temperature in unit nvme named Sensor 1. max=65261.8'C,min=-273.15'C. Unit: hwmon_nvme]
temp_sensor_2 OR temp3
[Temperature in unit nvme named Sensor 2. max=65261.8'C,min=-273.15'C. Unit: hwmon_nvme]
fan1
[Fan in unit thinkpad named fan1. Unit: hwmon_thinkpad]
fan2
[Fan in unit thinkpad named fan2. Unit: hwmon_thinkpad]
...
temp_cpu OR temp1
[Temperature in unit thinkpad named CPU. Unit: hwmon_thinkpad]
temp_gpu OR temp2
[Temperature in unit thinkpad named GPU. Unit: hwmon_thinkpad]
curr1
[Current in unit ucsi_source_psy_usbc000_0 named curr1. max=1.5A. Unit:
hwmon_ucsi_source_psy_usbc000_0]
in0
[Voltage in unit ucsi_source_psy_usbc000_0 named in0. max=5V,min=5V. Unit:
hwmon_ucsi_source_psy_usbc000_0]
```

As there may be multiple hwmon devices a range of PMU types are
reserved for their use and to identify the PMU as belonging to the
hwmon types.

Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
---
tools/perf/util/Build | 1 +
tools/perf/util/hwmon_pmu.c | 820 ++++++++++++++++++++++++++++++++++++
tools/perf/util/hwmon_pmu.h | 154 +++++++
tools/perf/util/pmu.h | 2 +
4 files changed, 977 insertions(+)
create mode 100644 tools/perf/util/hwmon_pmu.c
create mode 100644 tools/perf/util/hwmon_pmu.h

diff --git a/tools/perf/util/Build b/tools/perf/util/Build
index fa508e113dd0..9eb8b1c3df94 100644
--- a/tools/perf/util/Build
+++ b/tools/perf/util/Build
@@ -83,6 +83,7 @@ perf-util-y += pmu.o
perf-util-y += pmus.o
perf-util-y += pmu-flex.o
perf-util-y += pmu-bison.o
+perf-util-y += hwmon_pmu.o
perf-util-y += tool_pmu.o
perf-util-y += svghelper.o
perf-util-$(CONFIG_LIBTRACEEVENT) += trace-event-info.o
diff --git a/tools/perf/util/hwmon_pmu.c b/tools/perf/util/hwmon_pmu.c
new file mode 100644
index 000000000000..a8bc76721328
--- /dev/null
+++ b/tools/perf/util/hwmon_pmu.c
@@ -0,0 +1,820 @@
+// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
+#include "counts.h"
+#include "debug.h"
+#include "evsel.h"
+#include "hashmap.h"
+#include "hwmon_pmu.h"
+#include "pmu.h"
+#include <internal/xyarray.h>
+#include <internal/threadmap.h>
+#include <perf/threadmap.h>
+#include <sys/types.h>
+#include <ctype.h>
+#include <dirent.h>
+#include <fcntl.h>
+#include <api/fs/fs.h>
+#include <api/io.h>
+#include <linux/zalloc.h>
+
+const char * const hwmon_type_strs[HWMON_TYPE_MAX] = {
+ NULL,
+ "cpu",
+ "curr",
+ "energy",
+ "fan",
+ "humidity",
+ "in",
+ "intrusion",
+ "power",
+ "pwm",
+ "temp",
+};
+#define LONGEST_HWMON_TYPE_STR "intrusion"
+
+static const char *const hwmon_units[HWMON_TYPE_MAX] = {
+ NULL,
+ "V", /* cpu */
+ "A", /* curr */
+ "J", /* energy */
+ "rpm", /* fan */
+ "%", /* humidity */
+ "V", /* in */
+ "", /* intrusion */
+ "W", /* power */
+ "Hz", /* pwm */
+ "'C", /* temp */
+};
+
+const char * const hwmon_item_strs[HWMON_ITEM__MAX] = {
+ NULL,
+ "accuracy",
+ "alarm",
+ "auto_channels_temp",
+ "average",
+ "average_highest",
+ "average_interval",
+ "average_interval_max",
+ "average_interval_min",
+ "average_lowest",
+ "average_max",
+ "average_min",
+ "beep",
+ "cap",
+ "cap_hyst",
+ "cap_max",
+ "cap_min",
+ "crit",
+ "crit_hyst",
+ "div",
+ "emergency",
+ "emergency_hist",
+ "enable",
+ "fault",
+ "freq",
+ "highest",
+ "input",
+ "label",
+ "lcrit",
+ "lcrit_hyst",
+ "lowest",
+ "max",
+ "max_hyst",
+ "min",
+ "min_hyst",
+ "mod",
+ "offset",
+ "pulses",
+ "rated_max",
+ "rated_min",
+ "reset_history",
+ "target",
+ "type",
+ "vid",
+};
+#define LONGEST_HWMON_ITEM_STR "average_interval_max"
+
+struct hwmon_pmu {
+ struct perf_pmu pmu;
+ struct hashmap events;
+ int hwmon_dir_fd;
+};
+
+/**
+ * union hwmon_pmu_event_key: Key for hwmon_pmu->events as such each key
+ * represents an event.
+ *
+ * Related hwmon files start <type><number> that this key represents.
+ */
+union hwmon_pmu_event_key {
+ long type_and_num;
+ struct {
+ int num :16;
+ enum hwmon_type type :8;
+ };
+};
+
+/**
+ * struct hwmon_pmu_event_value: Value in hwmon_pmu->events.
+ *
+ * Hwmon files are of the form <type><number>_<item> and may have a suffix
+ * _alarm.
+ */
+struct hwmon_pmu_event_value {
+ /** @items: which item files are present. */
+ DECLARE_BITMAP(items, HWMON_ITEM__MAX);
+ /** @alarm_items: which item files are present. */
+ DECLARE_BITMAP(alarm_items, HWMON_ITEM__MAX);
+ /** @label: contents of <type><number>_label if present. */
+ char *label;
+ /** @name: name computed from label of the form <type>_<label>. */
+ char *name;
+};
+
+bool perf_pmu__is_hwmon(const struct perf_pmu *pmu)
+{
+ return pmu && pmu->type >= PERF_PMU_TYPE_HWMON_START &&
+ pmu->type <= PERF_PMU_TYPE_HWMON_END;
+}
+
+bool evsel__is_hwmon(const struct evsel *evsel)
+{
+ return perf_pmu__is_hwmon(evsel->pmu);
+}
+
+static size_t hwmon_pmu__event_hashmap_hash(long key, void *ctx __maybe_unused)
+{
+ return ((union hwmon_pmu_event_key)key).type_and_num;
+}
+
+static bool hwmon_pmu__event_hashmap_equal(long key1, long key2, void *ctx __maybe_unused)
+{
+ return ((union hwmon_pmu_event_key)key1).type_and_num ==
+ ((union hwmon_pmu_event_key)key2).type_and_num;
+}
+
+static int hwmon_strcmp(const void *a, const void *b)
+{
+ const char *sa = a;
+ const char * const *sb = b;
+
+ return strcmp(sa, *sb);
+}
+
+bool parse_hwmon_filename(const char *filename,
+ enum hwmon_type *type,
+ int *number,
+ enum hwmon_item *item,
+ bool *alarm)
+{
+ char fn_type[24];
+ const char **elem;
+ const char *fn_item = NULL;
+ size_t fn_item_len;
+
+ assert(strlen(LONGEST_HWMON_TYPE_STR) < sizeof(fn_type));
+ strlcpy(fn_type, filename, sizeof(fn_type));
+ for (size_t i = 0; i < sizeof(fn_type); i++) {
+ if (fn_type[i] >= '0' && fn_type[i] <= '9') {
+ fn_type[i] = '\0';
+ *number = strtoul(&filename[i], (char **)&fn_item, 10);
+ if (*fn_item == '_')
+ fn_item++;
+ break;
+ }
+ if (fn_type[i] == '_') {
+ fn_type[i] = '\0';
+ *number = -1;
+ fn_item = &filename[i + 1];
+ break;
+ }
+ }
+ if (fn_item == NULL || fn_type[0] == '\0' || (item != NULL && fn_item[0] == '\0')) {
+ pr_debug("hwmon_pmu: not a hwmon file '%s'\n", filename);
+ return false;
+ }
+ elem = bsearch(&fn_type, hwmon_type_strs + 1, ARRAY_SIZE(hwmon_type_strs) - 1,
+ sizeof(hwmon_type_strs[0]), hwmon_strcmp);
+ if (!elem) {
+ pr_debug("hwmon_pmu: not a hwmon type '%s' in file name '%s'\n",
+ fn_type, filename);
+ return false;
+ }
+
+ *type = elem - &hwmon_type_strs[0];
+ if (!item)
+ return true;
+
+ *alarm = false;
+ fn_item_len = strlen(fn_item);
+ if (fn_item_len > 6 && !strcmp(&fn_item[fn_item_len - 6], "_alarm")) {
+ assert(strlen(LONGEST_HWMON_ITEM_STR) < sizeof(fn_type));
+ strlcpy(fn_type, fn_item, fn_item_len - 6);
+ fn_item = fn_type;
+ *alarm = true;
+ }
+ elem = bsearch(fn_item, hwmon_item_strs + 1, ARRAY_SIZE(hwmon_item_strs) - 1,
+ sizeof(hwmon_item_strs[0]), hwmon_strcmp);
+ if (!elem) {
+ pr_debug("hwmon_pmu: not a hwmon item '%s' in file name '%s'\n",
+ fn_item, filename);
+ return false;
+ }
+ *item = elem - &hwmon_item_strs[0];
+ return true;
+}
+
+static void fix_name(char *p)
+{
+ char *s = strchr(p, '\n');
+
+ if (s)
+ *s = '\0';
+
+ while (*p != '\0') {
+ if (strchr(" :,/\n\t", *p))
+ *p = '_';
+ else
+ *p = tolower(*p);
+ p++;
+ }
+}
+
+static int hwmon_pmu__read_events(struct hwmon_pmu *pmu)
+{
+ DIR *dir;
+ struct dirent *ent;
+ int dup_fd, err = 0;
+ struct hashmap_entry *cur, *tmp;
+ size_t bkt;
+
+ if (pmu->pmu.sysfs_aliases_loaded)
+ return 0;
+
+ /* Use a dup-ed fd as closedir will close it. */
+ dup_fd = dup(pmu->hwmon_dir_fd);
+ if (dup_fd == -1)
+ return -ENOMEM;
+
+ dir = fdopendir(dup_fd);
+ if (!dir) {
+ close(dup_fd);
+ return -ENOMEM;
+ }
+
+ while ((ent = readdir(dir)) != NULL) {
+ enum hwmon_type type;
+ int number;
+ enum hwmon_item item;
+ bool alarm;
+ union hwmon_pmu_event_key key = {};
+ struct hwmon_pmu_event_value *value;
+
+ if (ent->d_type != DT_REG)
+ continue;
+
+ if (!parse_hwmon_filename(ent->d_name, &type, &number, &item, &alarm)) {
+ pr_debug("Not a hwmon file '%s'\n", ent->d_name);
+ continue;
+ }
+ key.num = number;
+ key.type = type;
+ if (!hashmap__find(&pmu->events, key.type_and_num, &value)) {
+ value = zalloc(sizeof(*value));
+ if (!value) {
+ err = -ENOMEM;
+ goto err_out;
+ }
+ err = hashmap__add(&pmu->events, key.type_and_num, value);
+ if (err) {
+ free(value);
+ err = -ENOMEM;
+ goto err_out;
+ }
+ }
+ __set_bit(item, alarm ? value->alarm_items : value->items);
+ if (item == HWMON_ITEM_LABEL) {
+ char buf[128];
+ int fd = openat(pmu->hwmon_dir_fd, ent->d_name, O_RDONLY);
+ ssize_t read_len;
+
+ if (fd < 0)
+ continue;
+
+ read_len = read(fd, buf, sizeof(buf));
+
+ while (read_len > 0 && buf[read_len - 1] == '\n')
+ read_len--;
+
+ if (read_len > 0)
+ buf[read_len] = '\0';
+
+ if (buf[0] == '\0') {
+ pr_debug("hwmon_pmu: empty label file %s %s\n",
+ pmu->pmu.name, ent->d_name);
+ close(fd);
+ continue;
+ }
+ value->label = strdup(buf);
+ if (!value->label) {
+ pr_debug("hwmon_pmu: memory allocation failure\n");
+ close(fd);
+ continue;
+ }
+ snprintf(buf, sizeof(buf), "%s_%s", hwmon_type_strs[type], value->label);
+ fix_name(buf);
+ value->name = strdup(buf);
+ if (!value->name)
+ pr_debug("hwmon_pmu: memory allocation failure\n");
+ close(fd);
+ }
+ }
+ hashmap__for_each_entry_safe((&pmu->events), cur, tmp, bkt) {
+ union hwmon_pmu_event_key key = {
+ .type_and_num = cur->key,
+ };
+ struct hwmon_pmu_event_value *value = cur->pvalue;
+
+ if (!test_bit(HWMON_ITEM_INPUT, value->items)) {
+ pr_debug("hwmon_pmu: removing event '%s%d' that has no input file\n",
+ hwmon_type_strs[key.type], key.num);
+ hashmap__delete(&pmu->events, key.type_and_num, &key, &value);
+ zfree(&value->label);
+ zfree(&value->name);
+ free(value);
+ }
+ }
+ pmu->pmu.sysfs_aliases_loaded = true;
+
+err_out:
+ closedir(dir);
+ return err;
+}
+
+struct perf_pmu *hwmon_pmu__new(struct list_head *pmus, int hwmon_dir, const char *sysfs_name, const char *name)
+{
+ char buf[32];
+ struct hwmon_pmu *hwm;
+
+ hwm = zalloc(sizeof(*hwm));
+ if (!hwm)
+ return NULL;
+
+
+ hwm->hwmon_dir_fd = hwmon_dir;
+ hwm->pmu.type = PERF_PMU_TYPE_HWMON_START + strtoul(sysfs_name + 5, NULL, 10);
+ if (hwm->pmu.type > PERF_PMU_TYPE_HWMON_END) {
+ pr_err("Unable to encode hwmon type from %s in valid PMU type\n", sysfs_name);
+ goto err_out;
+ }
+ snprintf(buf, sizeof(buf), "hwmon_%s", name);
+ fix_name(buf + 6);
+ hwm->pmu.name = strdup(buf);
+ if (!hwm->pmu.name)
+ goto err_out;
+ hwm->pmu.alias_name = strdup(sysfs_name);
+ if (!hwm->pmu.alias_name)
+ goto err_out;
+ hwm->pmu.cpus = perf_cpu_map__new("0");
+ if (!hwm->pmu.cpus)
+ goto err_out;
+ INIT_LIST_HEAD(&hwm->pmu.format);
+ INIT_LIST_HEAD(&hwm->pmu.aliases);
+ INIT_LIST_HEAD(&hwm->pmu.caps);
+ hashmap__init(&hwm->events, hwmon_pmu__event_hashmap_hash,
+ hwmon_pmu__event_hashmap_equal, /*ctx=*/NULL);
+
+ list_add_tail(&hwm->pmu.list, pmus);
+ return &hwm->pmu;
+err_out:
+ free((char *)hwm->pmu.name);
+ free(hwm->pmu.alias_name);
+ free(hwm);
+ close(hwmon_dir);
+ return NULL;
+}
+
+void hwmon_pmu__exit(struct perf_pmu *pmu)
+{
+ struct hwmon_pmu *hwm = container_of(pmu, struct hwmon_pmu, pmu);
+ struct hashmap_entry *cur, *tmp;
+ size_t bkt;
+
+ hashmap__for_each_entry_safe((&hwm->events), cur, tmp, bkt) {
+ struct hwmon_pmu_event_value *value = cur->pvalue;
+
+ zfree(&value->label);
+ zfree(&value->name);
+ free(value);
+ }
+ hashmap__clear(&hwm->events);
+ close (hwm->hwmon_dir_fd);
+}
+
+static size_t hwmon_pmu__describe_items(struct hwmon_pmu *hwm, char *out_buf, size_t out_buf_len,
+ union hwmon_pmu_event_key key,
+ const unsigned long *items, bool is_alarm)
+{
+ size_t bit;
+ char buf[64];
+ size_t len = 0;
+
+ for_each_set_bit(bit, items, HWMON_ITEM__MAX) {
+ int fd;
+
+ if (bit == HWMON_ITEM_LABEL || bit == HWMON_ITEM_INPUT)
+ continue;
+
+ snprintf(buf, sizeof(buf), "%s%d_%s%s",
+ hwmon_type_strs[key.type],
+ key.num,
+ hwmon_item_strs[bit],
+ is_alarm ? "_alarm" : "");
+ fd = openat(hwm->hwmon_dir_fd, buf, O_RDONLY);
+ if (fd > 0) {
+ ssize_t read_len = read(fd, buf, sizeof(buf));
+
+ while (read_len > 0 && buf[read_len - 1] == '\n')
+ read_len--;
+
+ if (read_len > 0) {
+ long long val;
+
+ buf[read_len] = '\0';
+ val = strtoll(buf, /*endptr=*/NULL, 10);
+ len += snprintf(out_buf + len, out_buf_len - len, "%s%s%s=%g%s",
+ len == 0 ? " " : ", ",
+ hwmon_item_strs[bit],
+ is_alarm ? "_alarm" : "",
+ (double)val / 1000.0,
+ hwmon_units[key.type]);
+ }
+ close(fd);
+ }
+ }
+ return len;
+}
+
+int hwmon_pmu__for_each_event(struct perf_pmu *pmu, void *state, pmu_event_callback cb)
+{
+ struct hwmon_pmu *hwm = container_of(pmu, struct hwmon_pmu, pmu);
+ struct hashmap_entry *cur;
+ size_t bkt;
+
+ if (hwmon_pmu__read_events(hwm))
+ return false;
+
+ hashmap__for_each_entry((&hwm->events), cur, bkt) {
+ static const char *const hwmon_scale_units[HWMON_TYPE_MAX] = {
+ NULL,
+ "0.001V", /* cpu */
+ "0.001A", /* curr */
+ "0.001J", /* energy */
+ "1rpm", /* fan */
+ "0.001%", /* humidity */
+ "0.001V", /* in */
+ NULL, /* intrusion */
+ "0.001W", /* power */
+ "1Hz", /* pwm */
+ "0.001'C", /* temp */
+ };
+ static const char *const hwmon_desc[HWMON_TYPE_MAX] = {
+ NULL,
+ "CPU core reference voltage", /* cpu */
+ "Current", /* curr */
+ "Cumulative energy use", /* energy */
+ "Fan", /* fan */
+ "Humidity", /* humidity */
+ "Voltage", /* in */
+ "Chassis intrusion detection", /* intrusion */
+ "Power use", /* power */
+ "Pulse width modulation fan control", /* pwm */
+ "Temperature", /* temp */
+ };
+ char alias_buf[64];
+ char desc_buf[256];
+ char encoding_buf[128];
+ union hwmon_pmu_event_key key = {
+ .type_and_num = cur->key,
+ };
+ struct hwmon_pmu_event_value *value = cur->pvalue;
+ struct pmu_event_info info = {
+ .pmu = pmu,
+ .name = value->name,
+ .alias = alias_buf,
+ .scale_unit = hwmon_scale_units[key.type],
+ .desc = desc_buf,
+ .long_desc = NULL,
+ .encoding_desc = encoding_buf,
+ .topic = "hwmon",
+ .pmu_name = pmu->name,
+ .event_type_desc = "Hwmon event",
+ };
+ int ret;
+ size_t len;
+
+ len = snprintf(alias_buf, sizeof(alias_buf), "%s%d",
+ hwmon_type_strs[key.type], key.num);
+ if (!info.name) {
+ info.name = info.alias;
+ info.alias = NULL;
+ }
+
+ len = snprintf(desc_buf, sizeof(desc_buf), "%s in unit %s named %s.",
+ hwmon_desc[key.type],
+ pmu->name + 6,
+ value->label ?: info.name);
+
+ len += hwmon_pmu__describe_items(hwm, desc_buf + len, sizeof(desc_buf) - len,
+ key, value->items, /*is_alarm=*/false);
+
+ len += hwmon_pmu__describe_items(hwm, desc_buf + len, sizeof(desc_buf) - len,
+ key, value->alarm_items, /*is_alarm=*/true);
+
+ snprintf(encoding_buf, sizeof(encoding_buf), "%s/config=0x%lx/",
+ pmu->name, cur->key);
+
+ ret = cb(state, &info);
+ if (ret)
+ return ret;
+ }
+ return 0;
+}
+
+size_t hwmon_pmu__num_events(struct perf_pmu *pmu)
+{
+ struct hwmon_pmu *hwm = container_of(pmu, struct hwmon_pmu, pmu);
+
+ hwmon_pmu__read_events(hwm);
+ return hashmap__size(&hwm->events);
+}
+
+bool hwmon_pmu__have_event(struct perf_pmu *pmu, const char *name)
+{
+ struct hwmon_pmu *hwm = container_of(pmu, struct hwmon_pmu, pmu);
+ enum hwmon_type type;
+ int number;
+ union hwmon_pmu_event_key key = {};
+ struct hashmap_entry *cur;
+ size_t bkt;
+
+ if (!parse_hwmon_filename(name, &type, &number, /*item=*/NULL, /*is_alarm=*/NULL))
+ return false;
+
+ if (hwmon_pmu__read_events(hwm))
+ return false;
+
+ key.type = type;
+ key.num = number;
+ if (hashmap_find(&hwm->events, key.type_and_num, /*value=*/NULL))
+ return true;
+ if (key.num != -1)
+ return false;
+ /* Item is of form <type>_ which means we should match <type>_<label>. */
+ hashmap__for_each_entry((&hwm->events), cur, bkt) {
+ struct hwmon_pmu_event_value *value = cur->pvalue;
+
+ key.type_and_num = cur->key;
+ if (key.type == type && value->name && !strcasecmp(name, value->name))
+ return true;
+ }
+ return false;
+}
+
+static int hwmon_pmu__config_term(const struct hwmon_pmu *hwm,
+ struct perf_event_attr *attr,
+ struct parse_events_term *term,
+ struct parse_events_error *err)
+{
+ if (term->type_term == PARSE_EVENTS__TERM_TYPE_USER) {
+ enum hwmon_type type;
+ int number;
+
+ if (parse_hwmon_filename(term->config, &type, &number,
+ /*item=*/NULL, /*is_alarm=*/NULL)) {
+ if (number == -1) {
+ /*
+ * Item is of form <type>_ which means we should
+ * match <type>_<label>.
+ */
+ struct hashmap_entry *cur;
+ size_t bkt;
+
+ attr->config = 0;
+ hashmap__for_each_entry((&hwm->events), cur, bkt) {
+ union hwmon_pmu_event_key key = {
+ .type_and_num = cur->key,
+ };
+ struct hwmon_pmu_event_value *value = cur->pvalue;
+
+ if (key.type == type && value->name &&
+ !strcasecmp(term->config, value->name)) {
+ attr->config = key.type_and_num;
+ break;
+ }
+ }
+ if (attr->config == 0)
+ return -EINVAL;
+ } else {
+ union hwmon_pmu_event_key key = {
+ .type = type,
+ .num = number,
+ };
+
+ attr->config = key.type_and_num;
+ }
+ return 0;
+ }
+ }
+ if (err) {
+ char *err_str;
+
+ parse_events_error__handle(err, term->err_val,
+ asprintf(&err_str,
+ "unexpected hwmon event term (%s) %s",
+ parse_events__term_type_str(term->type_term),
+ term->config) < 0
+ ? strdup("unexpected hwmon event term")
+ : err_str,
+ NULL);
+ }
+ return -EINVAL;
+}
+
+int hwmon_pmu__config_terms(const struct perf_pmu *pmu,
+ struct perf_event_attr *attr,
+ struct parse_events_terms *terms,
+ struct parse_events_error *err)
+{
+ const struct hwmon_pmu *hwm = container_of(pmu, struct hwmon_pmu, pmu);
+ struct parse_events_term *term;
+
+ assert(pmu->sysfs_aliases_loaded);
+ list_for_each_entry(term, &terms->terms, list) {
+ if (hwmon_pmu__config_term(hwm, attr, term, err))
+ return -EINVAL;
+ }
+
+ return 0;
+
+}
+
+int hwmon_pmu__check_alias(struct parse_events_terms *terms, struct perf_pmu_info *info,
+ struct parse_events_error *err)
+{
+ struct parse_events_term *term =
+ list_first_entry(&terms->terms, struct parse_events_term, list);
+
+ if (term->type_term == PARSE_EVENTS__TERM_TYPE_USER) {
+ enum hwmon_type type;
+ int number;
+
+ if (parse_hwmon_filename(term->config, &type, &number,
+ /*item=*/NULL, /*is_alarm=*/NULL)) {
+ info->unit = hwmon_units[type];
+ if (type == HWMON_TYPE_FAN || type == HWMON_TYPE_PWM ||
+ type == HWMON_TYPE_INTRUSION)
+ info->scale = 1;
+ else
+ info->scale = 0.001;
+ }
+ return 0;
+ }
+ if (err) {
+ char *err_str;
+
+ parse_events_error__handle(err, term->err_val,
+ asprintf(&err_str,
+ "unexpected hwmon event term (%s) %s",
+ parse_events__term_type_str(term->type_term),
+ term->config) < 0
+ ? strdup("unexpected hwmon event term")
+ : err_str,
+ NULL);
+ }
+ return -EINVAL;
+}
+
+int perf_pmus__read_hwmon_pmus(struct list_head *pmus)
+{
+ char *line = NULL;
+ DIR *class_hwmon_dir;
+ struct dirent *class_hwmon_ent;
+ char buf[PATH_MAX];
+ const char *sysfs = sysfs__mountpoint();
+
+ if (!sysfs)
+ return 0;
+
+ scnprintf(buf, sizeof(buf), "%s/class/hwmon/", sysfs);
+ class_hwmon_dir = opendir(buf);
+ if (!class_hwmon_dir)
+ return 0;
+
+ while ((class_hwmon_ent = readdir(class_hwmon_dir)) != NULL) {
+ size_t line_len;
+ int hwmon_dir, name_fd;
+ struct io io;
+
+ if (class_hwmon_ent->d_type != DT_LNK)
+ continue;
+
+ scnprintf(buf, sizeof(buf), "%s/class/hwmon/%s", sysfs, class_hwmon_ent->d_name);
+ hwmon_dir = open(buf, O_DIRECTORY);
+ if (hwmon_dir == -1) {
+ pr_debug("hwmon_pmu: not a directory: '%s/class/hwmon/%s'\n",
+ sysfs, class_hwmon_ent->d_name);
+ continue;
+ }
+ name_fd = openat(hwmon_dir, "name", O_RDONLY);
+ if (name_fd == -1) {
+ pr_debug("hwmon_pmu: failure to open '%s/class/hwmon/%s/name'\n",
+ sysfs, class_hwmon_ent->d_name);
+ close(hwmon_dir);
+ continue;
+ }
+ io__init(&io, name_fd, buf, sizeof(buf));
+ io__getline(&io, &line, &line_len);
+ if (line_len > 0 && line[line_len - 1] == '\n')
+ line[line_len - 1] = '\0';
+ hwmon_pmu__new(pmus, hwmon_dir, class_hwmon_ent->d_name, line);
+ close(name_fd);
+ }
+ free(line);
+ closedir(class_hwmon_dir);
+ return 0;
+}
+
+#define FD(e, x, y) (*(int *)xyarray__entry(e->core.fd, x, y))
+
+int evsel__hwmon_pmu_open(struct evsel *evsel,
+ struct perf_thread_map *threads,
+ int start_cpu_map_idx, int end_cpu_map_idx)
+{
+ struct hwmon_pmu *hwm = container_of(evsel->pmu, struct hwmon_pmu, pmu);
+ union hwmon_pmu_event_key key = {
+ .type_and_num = evsel->core.attr.config,
+ };
+ int idx = 0, thread = 0, nthreads, err = 0;
+
+ nthreads = perf_thread_map__nr(threads);
+ for (idx = start_cpu_map_idx; idx < end_cpu_map_idx; idx++) {
+ for (thread = 0; thread < nthreads; thread++) {
+ char buf[64];
+ int fd;
+
+ snprintf(buf, sizeof(buf), "%s%d_input",
+ hwmon_type_strs[key.type], key.num);
+
+ fd = openat(hwm->hwmon_dir_fd, buf, O_RDONLY);
+ FD(evsel, idx, thread) = fd;
+ if (fd < 0) {
+ err = -errno;
+ goto out_close;
+ }
+ }
+ }
+ return 0;
+out_close:
+ if (err)
+ threads->err_thread = thread;
+
+ do {
+ while (--thread >= 0) {
+ if (FD(evsel, idx, thread) >= 0)
+ close(FD(evsel, idx, thread));
+ FD(evsel, idx, thread) = -1;
+ }
+ thread = nthreads;
+ } while (--idx >= 0);
+ return err;
+}
+
+int evsel__hwmon_pmu_read(struct evsel *evsel, int cpu_map_idx, int thread)
+{
+ char buf[32];
+ int fd;
+ ssize_t len;
+ struct perf_counts_values *count, *old_count = NULL;
+
+ if (evsel->prev_raw_counts)
+ old_count = perf_counts(evsel->prev_raw_counts, cpu_map_idx, thread);
+
+ count = perf_counts(evsel->counts, cpu_map_idx, thread);
+ fd = FD(evsel, cpu_map_idx, thread);
+ len = pread(fd, buf, sizeof(buf), 0);
+ if (len <= 0) {
+ count->lost++;
+ return -EINVAL;
+ }
+ buf[len] = '\0';
+ if (old_count) {
+ count->val = old_count->val + strtoll(buf, NULL, 10);
+ count->run = old_count->run + 1;
+ count->ena = old_count->ena + 1;
+ } else {
+ count->val = strtoll(buf, NULL, 10);
+ count->run++;
+ count->ena++;
+ }
+ return 0;
+}
diff --git a/tools/perf/util/hwmon_pmu.h b/tools/perf/util/hwmon_pmu.h
new file mode 100644
index 000000000000..8061301fcd8e
--- /dev/null
+++ b/tools/perf/util/hwmon_pmu.h
@@ -0,0 +1,154 @@
+/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
+#ifndef __HWMON_PMU_H
+#define __HWMON_PMU_H
+
+#include "pmu.h"
+
+struct list_head;
+
+/**
+ * enum hwmon_type:
+ *
+ * As described in Documentation/hwmon/sysfs-interface.rst hwmon events are
+ * defined over multiple files of the form <type><num>_<item>. This enum
+ * captures potential <type> values.
+ *
+ * This enum is exposed for testing.
+ */
+enum hwmon_type {
+ HWMON_TYPE_NONE,
+
+ HWMON_TYPE_CPU,
+ HWMON_TYPE_CURR,
+ HWMON_TYPE_ENERGY,
+ HWMON_TYPE_FAN,
+ HWMON_TYPE_HUMIDITY,
+ HWMON_TYPE_IN,
+ HWMON_TYPE_INTRUSION,
+ HWMON_TYPE_POWER,
+ HWMON_TYPE_PWM,
+ HWMON_TYPE_TEMP,
+
+ HWMON_TYPE_MAX
+};
+
+/**
+ * enum hwmon_item:
+ *
+ * Similar to enum hwmon_type but describes the item part of a a sysfs filename.
+ *
+ * This enum is exposed for testing.
+ */
+enum hwmon_item {
+ HWMON_ITEM_NONE,
+
+ HWMON_ITEM_ACCURACY,
+ HWMON_ITEM_ALARM,
+ HWMON_ITEM_AUTO_CHANNELS_TEMP,
+ HWMON_ITEM_AVERAGE,
+ HWMON_ITEM_AVERAGE_HIGHEST,
+ HWMON_ITEM_AVERAGE_INTERVAL,
+ HWMON_ITEM_AVERAGE_INTERVAL_MAX,
+ HWMON_ITEM_AVERAGE_INTERVAL_MIN,
+ HWMON_ITEM_AVERAGE_LOWEST,
+ HWMON_ITEM_AVERAGE_MAX,
+ HWMON_ITEM_AVERAGE_MIN,
+ HWMON_ITEM_BEEP,
+ HWMON_ITEM_CAP,
+ HWMON_ITEM_CAP_HYST,
+ HWMON_ITEM_CAP_MAX,
+ HWMON_ITEM_CAP_MIN,
+ HWMON_ITEM_CRIT,
+ HWMON_ITEM_CRIT_HYST,
+ HWMON_ITEM_DIV,
+ HWMON_ITEM_EMERGENCY,
+ HWMON_ITEM_EMERGENCY_HIST,
+ HWMON_ITEM_ENABLE,
+ HWMON_ITEM_FAULT,
+ HWMON_ITEM_FREQ,
+ HWMON_ITEM_HIGHEST,
+ HWMON_ITEM_INPUT,
+ HWMON_ITEM_LABEL,
+ HWMON_ITEM_LCRIT,
+ HWMON_ITEM_LCRIT_HYST,
+ HWMON_ITEM_LOWEST,
+ HWMON_ITEM_MAX,
+ HWMON_ITEM_MAX_HYST,
+ HWMON_ITEM_MIN,
+ HWMON_ITEM_MIN_HYST,
+ HWMON_ITEM_MOD,
+ HWMON_ITEM_OFFSET,
+ HWMON_ITEM_PULSES,
+ HWMON_ITEM_RATED_MAX,
+ HWMON_ITEM_RATED_MIN,
+ HWMON_ITEM_RESET_HISTORY,
+ HWMON_ITEM_TARGET,
+ HWMON_ITEM_TYPE,
+ HWMON_ITEM_VID,
+
+ HWMON_ITEM__MAX,
+};
+
+/** Strings that correspond to enum hwmon_type. */
+extern const char * const hwmon_type_strs[HWMON_TYPE_MAX];
+/** Strings that correspond to enum hwmon_item. */
+extern const char * const hwmon_item_strs[HWMON_ITEM__MAX];
+
+bool perf_pmu__is_hwmon(const struct perf_pmu *pmu);
+bool evsel__is_hwmon(const struct evsel *evsel);
+
+/**
+ * parse_hwmon_filename() - Parse filename into constituent parts.
+ *
+ * @filename: To be parsed, of the form <type><number>_<item>.
+ * @type: The type defined from the parsed file name.
+ * @number: The number of the type, for example there may be more than 1 fan.
+ * @item: A hwmon <type><number> may have multiple associated items.
+ * @alarm: Is the filename for an alarm value?
+ *
+ * An example of a hwmon filename is "temp1_input". The type is temp for a
+ * temperature value. The number is 1. The item within the file is an input
+ * value - the temperature itself. This file doesn't contain an alarm value.
+ *
+ * Exposed for testing.
+ */
+bool parse_hwmon_filename(const char *filename,
+ enum hwmon_type *type,
+ int *number,
+ enum hwmon_item *item,
+ bool *alarm);
+
+/**
+ * hwmon_pmu__new() - Allocate and construct a hwmon PMU.
+ *
+ * @pmus: The list of PMUs to be added to.
+ * @hwmon_dir: An O_DIRECTORY file descriptor for a hwmon directory.
+ * @sysfs_name: Name of the hwmon sysfs directory like hwmon0.
+ * @name: The contents of the "name" file in the hwmon directory.
+ *
+ * Exposed for testing. Regular construction should happen via
+ * perf_pmus__read_hwmon_pmus.
+ */
+struct perf_pmu *hwmon_pmu__new(struct list_head *pmus, int hwmon_dir,
+ const char *sysfs_name, const char *name);
+void hwmon_pmu__exit(struct perf_pmu *pmu);
+
+int hwmon_pmu__for_each_event(struct perf_pmu *pmu, void *state, pmu_event_callback cb);
+size_t hwmon_pmu__num_events(struct perf_pmu *pmu);
+bool hwmon_pmu__have_event(struct perf_pmu *pmu, const char *name);
+int hwmon_pmu__config_terms(const struct perf_pmu *pmu,
+ struct perf_event_attr *attr,
+ struct parse_events_terms *terms,
+ struct parse_events_error *err);
+int hwmon_pmu__check_alias(struct parse_events_terms *terms, struct perf_pmu_info *info,
+ struct parse_events_error *err);
+
+int perf_pmus__read_hwmon_pmus(struct list_head *pmus);
+
+
+int evsel__hwmon_pmu_open(struct evsel *evsel,
+ struct perf_thread_map *threads,
+ int start_cpu_map_idx, int end_cpu_map_idx);
+int evsel__hwmon_pmu_read(struct evsel *evsel, int cpu_map_idx, int thread);
+
+#endif /* __HWMON_PMU_H */
diff --git a/tools/perf/util/pmu.h b/tools/perf/util/pmu.h
index e400db9e9eb1..10f23f48479b 100644
--- a/tools/perf/util/pmu.h
+++ b/tools/perf/util/pmu.h
@@ -37,6 +37,8 @@ struct perf_pmu_caps {
};

enum {
+ PERF_PMU_TYPE_HWMON_START = 0xFFFF0000,
+ PERF_PMU_TYPE_HWMON_END = 0xFFFFFFFD,
PERF_PMU_TYPE_TOOL = 0xFFFFFFFE,
PERF_PMU_TYPE_FAKE = 0xFFFFFFFF,
};
--
2.47.0.rc1.288.g06298d1525-goog