Commit 4810b761 authored by Ian Rogers's avatar Ian Rogers Committed by Namhyung Kim
Browse files

perf hwmon_pmu: Add hwmon filename parser 



hwmon filenames have a specific encoding that will be used to give a
config value. The encoding is described in:
Documentation/hwmon/sysfs-interface.rst
Add a function to parse the filename into consituent enums/ints that
will then be amenable to config encoding.

Note, things are done this way to allow mapping names to config and
back without the use of hash/dynamic lookup tables.

Signed-off-by: default avatarIan Rogers <irogers@google.com>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Yoshihiro Furudera <fj5100bi@fujitsu.com>
Cc: Howard Chu <howardchu95@gmail.com>
Cc: Ze Gao <zegao2021@gmail.com>
Cc: Changbin Du <changbin.du@huawei.com>
Cc: Junhao He <hejunhao3@huawei.com>
Cc: Weilin Wang <weilin.wang@intel.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Oliver Upton <oliver.upton@linux.dev>
Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com>
[namhyung: add #include <linux/string.h> for strlcpy()]
Link: https://lore.kernel.org/r/20241109003759.473460-3-irogers@google.com


Signed-off-by: default avatarNamhyung Kim <namhyung@kernel.org>
parent f4db95b6

tools/perf/util/Build

+1 −0
Original line number Diff line number Diff line
@@ -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

tools/perf/util/hwmon_pmu.c

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// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)

#include "debug.h"

#include "hwmon_pmu.h"

#include <assert.h>

#include <stddef.h>

#include <stdlib.h>

#include <string.h>

#include <linux/kernel.h>

#include <linux/string.h>



/** Strings that correspond to enum hwmon_type. */

static 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"



/** Strings that correspond to enum hwmon_item. */

static 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"



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; fn_type[i] != '\0'; 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 - 5);

		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;

}

tools/perf/util/hwmon_pmu.h

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/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */

#ifndef __HWMON_PMU_H

#define __HWMON_PMU_H



#include <stdbool.h>



/**

 * 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,

};



/**

 * 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);



#endif /* __HWMON_PMU_H */