diff mbox series

[1/2] cpupower: Introduce powercap intel-rapl library and powercap-info command

Message ID 20221123111810.16017-2-trenn@suse.de (mailing list archive)
State Accepted
Delegated to: Shuah Khan
Headers show
Series Introduce powercap userspace frontend | expand

Commit Message

Thomas Renninger Nov. 23, 2022, 11:18 a.m. UTC
Read out powercap zone information via:
cpupower powercap-info
and show the zone hierarchy to the user:

./cpupower powercap-info
Driver: intel-rapl
Powercap domain hierarchy:

Zone: package-0 (enabled)
Power consumption can be monitored in micro Watts

        Zone: core (disabled)
        Power consumption can be monitored in micro Watts

        Zone: uncore (disabled)
        Power consumption can be monitored in micro Watts

        Zone: dram (disabled)
        Power consumption can be monitored in micro Watts

There is a dummy -a option for powercap-info which can/should be used to
show more detailed info later. Like that other args can be added easily
later as well.

A enable/disable option via powercap-set subcommand is also an enhancement
for later.

Also not all RAPL domains are shown. The func walking through RAPL
subdomains is restricted and hardcoded to: "intel-rapl/intel-rapl:0"
On my system above powercap domains map to:
intel-rapl/intel-rapl:0
-> pack (age-0)
intel-rapl/intel-rapl:0/intel-rapl:0:0
-> core
intel-rapl/intel-rapl:0/intel-rapl:0:1
-> uncore

Missing ones on my system are:
intel-rapl-mmio/intel-rapl-mmio:0
-> pack (age-0)

intel-rapl/intel-rapl:1
-> psys

This could get enhanced in:
struct powercap_zone *powercap_init_zones()
and adopted to walk through all intel-rapl zones, but
also to other powercap drivers like dtpm
(Dynamic Thermal Power Management framework),
cmp with: drivers/powercap/dtpm_*

Signed-off-by: Thomas Renninger <trenn@suse.de>
CC: Shuah Khan <skhan@linuxfoundation.org>
---
 tools/power/cpupower/Makefile                 |  14 +-
 tools/power/cpupower/lib/powercap.c           | 290 ++++++++++++++++++
 tools/power/cpupower/lib/powercap.h           |  54 ++++
 .../cpupower/man/cpupower-powercap-info.1     |  25 ++
 tools/power/cpupower/utils/builtin.h          |   2 +
 tools/power/cpupower/utils/cpupower.c         |   1 +
 tools/power/cpupower/utils/powercap-info.c    | 117 +++++++
 7 files changed, 499 insertions(+), 4 deletions(-)
 create mode 100644 tools/power/cpupower/lib/powercap.c
 create mode 100644 tools/power/cpupower/lib/powercap.h
 create mode 100644 tools/power/cpupower/man/cpupower-powercap-info.1
 create mode 100644 tools/power/cpupower/utils/powercap-info.c

Comments

kernel test robot Nov. 25, 2022, 12:06 a.m. UTC | #1
Hi Thomas,

I love your patch! Perhaps something to improve:

[auto build test WARNING on linus/master]
[also build test WARNING on v6.1-rc6 next-20221124]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Thomas-Renninger/Introduce-powercap-userspace-frontend/20221123-192046
patch link:    https://lore.kernel.org/r/20221123111810.16017-2-trenn%40suse.de
patch subject: [PATCH 1/2] cpupower: Introduce powercap intel-rapl library and powercap-info command
reproduce:
        # https://github.com/intel-lab-lkp/linux/commit/bdc275ee9ce3a2a644508a3af2ef98996196ed45
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Thomas-Renninger/Introduce-powercap-userspace-frontend/20221123-192046
        git checkout bdc275ee9ce3a2a644508a3af2ef98996196ed45
        make menuconfig
        # enable CONFIG_COMPILE_TEST, CONFIG_WARN_MISSING_DOCUMENTS, CONFIG_WARN_ABI_ERRORS
        make htmldocs

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> Warning: tools/power/cpupower/man/cpupower-powercap-info.1 references a file that doesn't exist: Documentation/power/powercap/powercap.txt
diff mbox series

Patch

diff --git a/tools/power/cpupower/Makefile b/tools/power/cpupower/Makefile
index e9b6de314654..9fd3b309b3a6 100644
--- a/tools/power/cpupower/Makefile
+++ b/tools/power/cpupower/Makefile
@@ -133,7 +133,7 @@  UTIL_OBJS =  utils/helpers/amd.o utils/helpers/msr.o \
 	utils/idle_monitor/mperf_monitor.o utils/idle_monitor/cpupower-monitor.o \
 	utils/cpupower.o utils/cpufreq-info.o utils/cpufreq-set.o \
 	utils/cpupower-set.o utils/cpupower-info.o utils/cpuidle-info.o \
-	utils/cpuidle-set.o
+	utils/cpuidle-set.o utils/powercap-info.o
 
 UTIL_SRC := $(UTIL_OBJS:.o=.c)
 
@@ -143,9 +143,12 @@  UTIL_HEADERS = utils/helpers/helpers.h utils/idle_monitor/cpupower-monitor.h \
 	utils/helpers/bitmask.h \
 	utils/idle_monitor/idle_monitors.h utils/idle_monitor/idle_monitors.def
 
-LIB_HEADERS = 	lib/cpufreq.h lib/cpupower.h lib/cpuidle.h lib/acpi_cppc.h
-LIB_SRC = 	lib/cpufreq.c lib/cpupower.c lib/cpuidle.c lib/acpi_cppc.c
-LIB_OBJS = 	lib/cpufreq.o lib/cpupower.o lib/cpuidle.o lib/acpi_cppc.o
+LIB_HEADERS = 	lib/cpufreq.h lib/cpupower.h lib/cpuidle.h lib/acpi_cppc.h \
+	lib/powercap.h
+LIB_SRC = 	lib/cpufreq.c lib/cpupower.c lib/cpuidle.c lib/acpi_cppc.c \
+	lib/powercap.c
+LIB_OBJS = 	lib/cpufreq.o lib/cpupower.o lib/cpuidle.o lib/acpi_cppc.o \
+	lib/powercap.o
 LIB_OBJS :=	$(addprefix $(OUTPUT),$(LIB_OBJS))
 
 override CFLAGS +=	-pipe
@@ -276,6 +279,7 @@  install-lib: libcpupower
 	$(INSTALL) -d $(DESTDIR)${includedir}
 	$(INSTALL_DATA) lib/cpufreq.h $(DESTDIR)${includedir}/cpufreq.h
 	$(INSTALL_DATA) lib/cpuidle.h $(DESTDIR)${includedir}/cpuidle.h
+	$(INSTALL_DATA) lib/powercap.h $(DESTDIR)${includedir}/powercap.h
 
 install-tools: $(OUTPUT)cpupower
 	$(INSTALL) -d $(DESTDIR)${bindir}
@@ -292,6 +296,7 @@  install-man:
 	$(INSTALL_DATA) -D man/cpupower-set.1 $(DESTDIR)${mandir}/man1/cpupower-set.1
 	$(INSTALL_DATA) -D man/cpupower-info.1 $(DESTDIR)${mandir}/man1/cpupower-info.1
 	$(INSTALL_DATA) -D man/cpupower-monitor.1 $(DESTDIR)${mandir}/man1/cpupower-monitor.1
+	$(INSTALL_DATA) -D man/cpupower-powercap-info.1 $(DESTDIR)${mandir}/man1/cpupower-powercap-info.1
 
 install-gmo: create-gmo
 	$(INSTALL) -d $(DESTDIR)${localedir}
@@ -321,6 +326,7 @@  uninstall:
 	- rm -f $(DESTDIR)${mandir}/man1/cpupower-set.1
 	- rm -f $(DESTDIR)${mandir}/man1/cpupower-info.1
 	- rm -f $(DESTDIR)${mandir}/man1/cpupower-monitor.1
+	- rm -f $(DESTDIR)${mandir}/man1/cpupower-powercap-info.1
 	- for HLANG in $(LANGUAGES); do \
 		rm -f $(DESTDIR)${localedir}/$$HLANG/LC_MESSAGES/cpupower.mo; \
 	  done;
diff --git a/tools/power/cpupower/lib/powercap.c b/tools/power/cpupower/lib/powercap.c
new file mode 100644
index 000000000000..0ce29ee4c2e4
--- /dev/null
+++ b/tools/power/cpupower/lib/powercap.c
@@ -0,0 +1,290 @@ 
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *  (C) 2016 SUSE Software Solutions GmbH
+ *           Thomas Renninger <trenn@suse.de>
+ */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <dirent.h>
+
+#include "powercap.h"
+
+static unsigned int sysfs_read_file(const char *path, char *buf, size_t buflen)
+{
+	int fd;
+	ssize_t numread;
+
+	fd = open(path, O_RDONLY);
+	if (fd == -1)
+		return 0;
+
+	numread = read(fd, buf, buflen - 1);
+	if (numread < 1) {
+		close(fd);
+		return 0;
+	}
+
+	buf[numread] = '\0';
+	close(fd);
+
+	return (unsigned int) numread;
+}
+
+static int sysfs_get_enabled(char *path, int *mode)
+{
+	int fd;
+	char yes_no;
+
+	*mode = 0;
+
+	fd = open(path, O_RDONLY);
+	if (fd == -1)
+		return -1;
+
+	if (read(fd, &yes_no, 1) != 1) {
+		close(fd);
+		return -1;
+	}
+
+	if (yes_no == '1') {
+		*mode = 1;
+		return 0;
+	} else if (yes_no == '0') {
+		return 0;
+	}
+	return -1;
+}
+
+int powercap_get_enabled(int *mode)
+{
+	char path[SYSFS_PATH_MAX] = PATH_TO_POWERCAP "/intel-rapl/enabled";
+
+	return sysfs_get_enabled(path, mode);
+}
+
+/*
+ * Hardcoded, because rapl is the only powercap implementation
+- * this needs to get more generic if more powercap implementations
+ * should show up
+ */
+int powercap_get_driver(char *driver, int buflen)
+{
+	char file[SYSFS_PATH_MAX] = PATH_TO_RAPL;
+
+	struct stat statbuf;
+
+	if (stat(file, &statbuf) != 0 || !S_ISDIR(statbuf.st_mode)) {
+		driver = "";
+		return -1;
+	} else if (buflen > 10) {
+		strcpy(driver, "intel-rapl");
+		return 0;
+	} else
+		return -1;
+}
+
+enum powercap_get64 {
+	GET_ENERGY_UJ,
+	GET_MAX_ENERGY_RANGE_UJ,
+	GET_POWER_UW,
+	GET_MAX_POWER_RANGE_UW,
+	MAX_GET_64_FILES
+};
+
+static const char *powercap_get64_files[MAX_GET_64_FILES] = {
+	[GET_POWER_UW] = "power_uw",
+	[GET_MAX_POWER_RANGE_UW] = "max_power_range_uw",
+	[GET_ENERGY_UJ] = "energy_uj",
+	[GET_MAX_ENERGY_RANGE_UJ] = "max_energy_range_uj",
+};
+
+static int sysfs_powercap_get64_val(struct powercap_zone *zone,
+				      enum powercap_get64 which,
+				      uint64_t *val)
+{
+	char file[SYSFS_PATH_MAX] = PATH_TO_POWERCAP "/";
+	int ret;
+	char buf[MAX_LINE_LEN];
+
+	strcat(file, zone->sys_name);
+	strcat(file, "/");
+	strcat(file, powercap_get64_files[which]);
+
+	ret = sysfs_read_file(file, buf, MAX_LINE_LEN);
+	if (ret < 0)
+		return ret;
+	if (ret == 0)
+		return -1;
+
+	*val = strtoll(buf, NULL, 10);
+	return 0;
+}
+
+int powercap_get_max_energy_range_uj(struct powercap_zone *zone, uint64_t *val)
+{
+	return sysfs_powercap_get64_val(zone, GET_MAX_ENERGY_RANGE_UJ, val);
+}
+
+int powercap_get_energy_uj(struct powercap_zone *zone, uint64_t *val)
+{
+	return sysfs_powercap_get64_val(zone, GET_ENERGY_UJ, val);
+}
+
+int powercap_get_max_power_range_uw(struct powercap_zone *zone, uint64_t *val)
+{
+	return sysfs_powercap_get64_val(zone, GET_MAX_POWER_RANGE_UW, val);
+}
+
+int powercap_get_power_uw(struct powercap_zone *zone, uint64_t *val)
+{
+	return sysfs_powercap_get64_val(zone, GET_POWER_UW, val);
+}
+
+int powercap_zone_get_enabled(struct powercap_zone *zone, int *mode)
+{
+	char path[SYSFS_PATH_MAX] = PATH_TO_POWERCAP;
+
+	if ((strlen(PATH_TO_POWERCAP) + strlen(zone->sys_name)) +
+	    strlen("/enabled") + 1 >= SYSFS_PATH_MAX)
+		return -1;
+
+	strcat(path, "/");
+	strcat(path, zone->sys_name);
+	strcat(path, "/enabled");
+
+	return sysfs_get_enabled(path, mode);
+}
+
+int powercap_zone_set_enabled(struct powercap_zone *zone, int mode)
+{
+	/* To be done if needed */
+	return 0;
+}
+
+
+int powercap_read_zone(struct powercap_zone *zone)
+{
+	struct dirent *dent;
+	DIR *zone_dir;
+	char sysfs_dir[SYSFS_PATH_MAX] = PATH_TO_POWERCAP;
+	struct powercap_zone *child_zone;
+	char file[SYSFS_PATH_MAX] = PATH_TO_POWERCAP;
+	int i, ret = 0;
+	uint64_t val = 0;
+
+	strcat(sysfs_dir, "/");
+	strcat(sysfs_dir, zone->sys_name);
+
+	zone_dir = opendir(sysfs_dir);
+	if (zone_dir == NULL)
+		return -1;
+
+	strcat(file, "/");
+	strcat(file, zone->sys_name);
+	strcat(file, "/name");
+	sysfs_read_file(file, zone->name, MAX_LINE_LEN);
+	if (zone->parent)
+		zone->tree_depth = zone->parent->tree_depth + 1;
+	ret = powercap_get_energy_uj(zone, &val);
+	if (ret == 0)
+		zone->has_energy_uj = 1;
+	ret = powercap_get_power_uw(zone, &val);
+	if (ret == 0)
+		zone->has_power_uw = 1;
+
+	while ((dent = readdir(zone_dir)) != NULL) {
+		struct stat st;
+
+		if (strcmp(dent->d_name, ".") == 0 || strcmp(dent->d_name, "..") == 0)
+			continue;
+
+		if (stat(dent->d_name, &st) != 0 || !S_ISDIR(st.st_mode))
+			if (fstatat(dirfd(zone_dir), dent->d_name, &st, 0) < 0)
+				continue;
+
+		if (strncmp(dent->d_name, "intel-rapl:", 11) != 0)
+			continue;
+
+		child_zone = calloc(1, sizeof(struct powercap_zone));
+		if (child_zone == NULL)
+			return -1;
+		for (i = 0; i < POWERCAP_MAX_CHILD_ZONES; i++) {
+			if (zone->children[i] == NULL) {
+				zone->children[i] = child_zone;
+				break;
+			}
+			if (i == POWERCAP_MAX_CHILD_ZONES - 1) {
+				free(child_zone);
+				fprintf(stderr, "Reached POWERCAP_MAX_CHILD_ZONES %d\n",
+				       POWERCAP_MAX_CHILD_ZONES);
+				return -1;
+			}
+		}
+		strcpy(child_zone->sys_name, zone->sys_name);
+		strcat(child_zone->sys_name, "/");
+		strcat(child_zone->sys_name, dent->d_name);
+		child_zone->parent = zone;
+		if (zone->tree_depth >= POWERCAP_MAX_TREE_DEPTH) {
+			fprintf(stderr, "Maximum zone hierarchy depth[%d] reached\n",
+				POWERCAP_MAX_TREE_DEPTH);
+			ret = -1;
+			break;
+		}
+		powercap_read_zone(child_zone);
+	}
+	closedir(zone_dir);
+	return ret;
+}
+
+struct powercap_zone *powercap_init_zones(void)
+{
+	int enabled;
+	struct powercap_zone *root_zone;
+	int ret;
+	char file[SYSFS_PATH_MAX] = PATH_TO_RAPL "/enabled";
+
+	ret = sysfs_get_enabled(file, &enabled);
+
+	if (ret)
+		return NULL;
+
+	if (!enabled)
+		return NULL;
+
+	root_zone = calloc(1, sizeof(struct powercap_zone));
+	if (!root_zone)
+		return NULL;
+
+	strcpy(root_zone->sys_name, "intel-rapl/intel-rapl:0");
+
+	powercap_read_zone(root_zone);
+
+	return root_zone;
+}
+
+/* Call function *f on the passed zone and all its children */
+
+int powercap_walk_zones(struct powercap_zone *zone,
+			int (*f)(struct powercap_zone *zone))
+{
+	int i, ret;
+
+	if (!zone)
+		return -1;
+
+	ret = f(zone);
+	if (ret)
+		return ret;
+
+	for (i = 0; i < POWERCAP_MAX_CHILD_ZONES; i++) {
+		if (zone->children[i] != NULL)
+			powercap_walk_zones(zone->children[i], f);
+	}
+	return 0;
+}
diff --git a/tools/power/cpupower/lib/powercap.h b/tools/power/cpupower/lib/powercap.h
new file mode 100644
index 000000000000..c049c109f22f
--- /dev/null
+++ b/tools/power/cpupower/lib/powercap.h
@@ -0,0 +1,54 @@ 
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ *  (C) 2016 SUSE Software Solutions GmbH
+ *           Thomas Renninger <trenn@suse.de>
+ */
+
+#ifndef __CPUPOWER_RAPL_H__
+#define __CPUPOWER_RAPL_H__
+
+#define PATH_TO_POWERCAP "/sys/devices/virtual/powercap"
+#define PATH_TO_RAPL "/sys/devices/virtual/powercap/intel-rapl"
+#define PATH_TO_RAPL_CLASS "/sys/devices/virtual/powercap/intel-rapl"
+
+#define POWERCAP_MAX_CHILD_ZONES 10
+#define POWERCAP_MAX_TREE_DEPTH 10
+
+#define MAX_LINE_LEN 4096
+#define SYSFS_PATH_MAX 255
+
+#include <stdint.h>
+
+struct powercap_zone {
+	char name[MAX_LINE_LEN];
+	/*
+	 * sys_name relative to PATH_TO_POWERCAP,
+	 * do not forget the / in between
+	 */
+	char sys_name[SYSFS_PATH_MAX];
+	int tree_depth;
+	struct powercap_zone *parent;
+	struct powercap_zone *children[POWERCAP_MAX_CHILD_ZONES];
+	/* More possible caps or attributes to be added? */
+	uint32_t has_power_uw:1,
+		 has_energy_uj:1;
+
+};
+
+int powercap_walk_zones(struct powercap_zone *zone,
+			int (*f)(struct powercap_zone *zone));
+
+struct powercap_zone *powercap_init_zones(void);
+int powercap_get_enabled(int *mode);
+int powercap_set_enabled(int mode);
+int powercap_get_driver(char *driver, int buflen);
+
+int powercap_get_max_energy_range_uj(struct powercap_zone *zone, uint64_t *val);
+int powercap_get_energy_uj(struct powercap_zone *zone, uint64_t *val);
+int powercap_get_max_power_range_uw(struct powercap_zone *zone, uint64_t *val);
+int powercap_get_power_uw(struct powercap_zone *zone, uint64_t *val);
+int powercap_zone_get_enabled(struct powercap_zone *zone, int *mode);
+int powercap_zone_set_enabled(struct powercap_zone *zone, int mode);
+
+
+#endif /* __CPUPOWER_RAPL_H__ */
diff --git a/tools/power/cpupower/man/cpupower-powercap-info.1 b/tools/power/cpupower/man/cpupower-powercap-info.1
new file mode 100644
index 000000000000..df3087000efb
--- /dev/null
+++ b/tools/power/cpupower/man/cpupower-powercap-info.1
@@ -0,0 +1,25 @@ 
+.TH CPUPOWER\-POWERCAP\-INFO "1" "05/08/2016" "" "cpupower Manual"
+.SH NAME
+cpupower\-powercap\-info \- Shows powercapping related kernel and hardware configurations
+.SH SYNOPSIS
+.ft B
+.B cpupower powercap-info
+
+.SH DESCRIPTION
+\fBcpupower powercap-info \fP shows kernel powercapping subsystem information.
+This needs hardware support and a loaded powercapping driver (at this time only
+intel_rapl driver exits) exporting hardware values userspace via sysfs.
+
+Some options are platform wide, some affect single cores. By default values
+of core zero are displayed only. cpupower --cpu all cpuinfo will show the
+settings of all cores, see cpupower(1) how to choose specific cores.
+
+.SH "DOCUMENTATION"
+
+kernel sources:
+Documentation/power/powercap/powercap.txt
+
+
+.SH "SEE ALSO"
+
+cpupower(1)
diff --git a/tools/power/cpupower/utils/builtin.h b/tools/power/cpupower/utils/builtin.h
index f7065ae60a14..e1caefd467cd 100644
--- a/tools/power/cpupower/utils/builtin.h
+++ b/tools/power/cpupower/utils/builtin.h
@@ -8,6 +8,8 @@  extern int cmd_freq_set(int argc, const char **argv);
 extern int cmd_freq_info(int argc, const char **argv);
 extern int cmd_idle_set(int argc, const char **argv);
 extern int cmd_idle_info(int argc, const char **argv);
+extern int cmd_cap_info(int argc, const char **argv);
+extern int cmd_cap_set(int argc, const char **argv);
 extern int cmd_monitor(int argc, const char **argv);
 
 #endif
diff --git a/tools/power/cpupower/utils/cpupower.c b/tools/power/cpupower/utils/cpupower.c
index 8ac3304a9957..9ec973165af1 100644
--- a/tools/power/cpupower/utils/cpupower.c
+++ b/tools/power/cpupower/utils/cpupower.c
@@ -54,6 +54,7 @@  static struct cmd_struct commands[] = {
 	{ "frequency-set",	cmd_freq_set,	1	},
 	{ "idle-info",		cmd_idle_info,	0	},
 	{ "idle-set",		cmd_idle_set,	1	},
+	{ "powercap-info",	cmd_cap_info,	0	},
 	{ "set",		cmd_set,	1	},
 	{ "info",		cmd_info,	0	},
 	{ "monitor",		cmd_monitor,	0	},
diff --git a/tools/power/cpupower/utils/powercap-info.c b/tools/power/cpupower/utils/powercap-info.c
new file mode 100644
index 000000000000..3ea4486f1a0e
--- /dev/null
+++ b/tools/power/cpupower/utils/powercap-info.c
@@ -0,0 +1,117 @@ 
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *  (C) 2016 SUSE Software Solutions GmbH
+ *           Thomas Renninger <trenn@suse.de>
+ */
+
+#include <unistd.h>
+#include <stdio.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+
+#include <getopt.h>
+
+#include "powercap.h"
+#include "helpers/helpers.h"
+
+int powercap_show_all;
+
+static struct option info_opts[] = {
+	{ "all",		no_argument,		 NULL,	 'a'},
+	{ },
+};
+
+static int powercap_print_one_zone(struct powercap_zone *zone)
+{
+	int mode, i, ret = 0;
+	char pr_prefix[1024] = "";
+
+	for (i = 0; i < zone->tree_depth && i < POWERCAP_MAX_TREE_DEPTH; i++)
+		strcat(pr_prefix, "\t");
+
+	printf("%sZone: %s", pr_prefix, zone->name);
+	ret = powercap_zone_get_enabled(zone, &mode);
+	if (ret < 0)
+		return ret;
+	printf(" (%s)\n", mode ? "enabled" : "disabled");
+
+	if (zone->has_power_uw)
+		printf(_("%sPower can be monitored in micro Jules\n"),
+		       pr_prefix);
+
+	if (zone->has_energy_uj)
+		printf(_("%sPower can be monitored in micro Watts\n"),
+		       pr_prefix);
+
+	printf("\n");
+
+	if (ret != 0)
+		return ret;
+	return ret;
+}
+
+static int powercap_show(void)
+{
+	struct powercap_zone *root_zone;
+	char line[MAX_LINE_LEN] = "";
+	int ret, val;
+
+	ret = powercap_get_driver(line, MAX_LINE_LEN);
+	if (ret < 0) {
+		printf(_("No powercapping driver loaded\n"));
+		return ret;
+	}
+
+	printf("Driver: %s\n", line);
+	ret = powercap_get_enabled(&val);
+	if (ret < 0)
+		return ret;
+	if (!val) {
+		printf(_("Powercapping is disabled\n"));
+		return -1;
+	}
+
+	printf(_("Powercap domain hierarchy:\n\n"));
+	root_zone = powercap_init_zones();
+
+	if (root_zone == NULL) {
+		printf(_("No powercap info found\n"));
+		return 1;
+	}
+
+	powercap_walk_zones(root_zone, powercap_print_one_zone);
+
+	return 0;
+}
+
+int cmd_cap_set(int argc, char **argv)
+{
+	return 0;
+};
+int cmd_cap_info(int argc, char **argv)
+{
+	int ret = 0, cont = 1;
+
+	do {
+		ret = getopt_long(argc, argv, "a", info_opts, NULL);
+		switch (ret) {
+		case '?':
+			cont = 0;
+			break;
+		case -1:
+			cont = 0;
+			break;
+		case 'a':
+			powercap_show_all = 1;
+			break;
+		default:
+			fprintf(stderr, _("invalid or unknown argument\n"));
+			return EXIT_FAILURE;
+		}
+	} while (cont);
+
+	powercap_show();
+	return 0;
+}