linux-stable/arch/tile/kernel/sysfs.c
Chris Metcalf 80f184108e tile: support reporting Tilera hypervisor statistics
Newer hypervisors have an API for reporting per-cpu statistics
information.  This change allows seeing that information via
/sys/devices/system/cpu/cpuN/hv_stats file for each core.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
2013-09-03 14:51:36 -04:00

269 lines
7.1 KiB
C

/*
* Copyright 2011 Tilera Corporation. All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation, version 2.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
* NON INFRINGEMENT. See the GNU General Public License for
* more details.
*
* /sys entry support.
*/
#include <linux/device.h>
#include <linux/cpu.h>
#include <linux/slab.h>
#include <linux/smp.h>
#include <linux/stat.h>
#include <hv/hypervisor.h>
/* Return a string queried from the hypervisor, truncated to page size. */
static ssize_t get_hv_confstr(char *page, int query)
{
ssize_t n = hv_confstr(query, (unsigned long)page, PAGE_SIZE - 1);
n = n < 0 ? 0 : min(n, (ssize_t)PAGE_SIZE - 1) - 1;
if (n)
page[n++] = '\n';
page[n] = '\0';
return n;
}
static ssize_t chip_width_show(struct device *dev,
struct device_attribute *attr,
char *page)
{
return sprintf(page, "%u\n", smp_width);
}
static DEVICE_ATTR(chip_width, 0444, chip_width_show, NULL);
static ssize_t chip_height_show(struct device *dev,
struct device_attribute *attr,
char *page)
{
return sprintf(page, "%u\n", smp_height);
}
static DEVICE_ATTR(chip_height, 0444, chip_height_show, NULL);
static ssize_t chip_serial_show(struct device *dev,
struct device_attribute *attr,
char *page)
{
return get_hv_confstr(page, HV_CONFSTR_CHIP_SERIAL_NUM);
}
static DEVICE_ATTR(chip_serial, 0444, chip_serial_show, NULL);
static ssize_t chip_revision_show(struct device *dev,
struct device_attribute *attr,
char *page)
{
return get_hv_confstr(page, HV_CONFSTR_CHIP_REV);
}
static DEVICE_ATTR(chip_revision, 0444, chip_revision_show, NULL);
static ssize_t type_show(struct device *dev,
struct device_attribute *attr,
char *page)
{
return sprintf(page, "tilera\n");
}
static DEVICE_ATTR(type, 0444, type_show, NULL);
#define HV_CONF_ATTR(name, conf) \
static ssize_t name ## _show(struct device *dev, \
struct device_attribute *attr, \
char *page) \
{ \
return get_hv_confstr(page, conf); \
} \
static DEVICE_ATTR(name, 0444, name ## _show, NULL);
HV_CONF_ATTR(version, HV_CONFSTR_HV_SW_VER)
HV_CONF_ATTR(config_version, HV_CONFSTR_HV_CONFIG_VER)
HV_CONF_ATTR(board_part, HV_CONFSTR_BOARD_PART_NUM)
HV_CONF_ATTR(board_serial, HV_CONFSTR_BOARD_SERIAL_NUM)
HV_CONF_ATTR(board_revision, HV_CONFSTR_BOARD_REV)
HV_CONF_ATTR(board_description, HV_CONFSTR_BOARD_DESC)
HV_CONF_ATTR(mezz_part, HV_CONFSTR_MEZZ_PART_NUM)
HV_CONF_ATTR(mezz_serial, HV_CONFSTR_MEZZ_SERIAL_NUM)
HV_CONF_ATTR(mezz_revision, HV_CONFSTR_MEZZ_REV)
HV_CONF_ATTR(mezz_description, HV_CONFSTR_MEZZ_DESC)
HV_CONF_ATTR(cpumod_part, HV_CONFSTR_CPUMOD_PART_NUM)
HV_CONF_ATTR(cpumod_serial, HV_CONFSTR_CPUMOD_SERIAL_NUM)
HV_CONF_ATTR(cpumod_revision, HV_CONFSTR_CPUMOD_REV)
HV_CONF_ATTR(cpumod_description,HV_CONFSTR_CPUMOD_DESC)
HV_CONF_ATTR(switch_control, HV_CONFSTR_SWITCH_CONTROL)
static struct attribute *board_attrs[] = {
&dev_attr_board_part.attr,
&dev_attr_board_serial.attr,
&dev_attr_board_revision.attr,
&dev_attr_board_description.attr,
&dev_attr_mezz_part.attr,
&dev_attr_mezz_serial.attr,
&dev_attr_mezz_revision.attr,
&dev_attr_mezz_description.attr,
&dev_attr_cpumod_part.attr,
&dev_attr_cpumod_serial.attr,
&dev_attr_cpumod_revision.attr,
&dev_attr_cpumod_description.attr,
&dev_attr_switch_control.attr,
NULL
};
static struct attribute_group board_attr_group = {
.name = "board",
.attrs = board_attrs,
};
static struct bin_attribute hvconfig_bin;
static ssize_t
hvconfig_bin_read(struct file *filp, struct kobject *kobj,
struct bin_attribute *bin_attr,
char *buf, loff_t off, size_t count)
{
static size_t size;
/* Lazily learn the true size (minus the trailing NUL). */
if (size == 0)
size = hv_confstr(HV_CONFSTR_HV_CONFIG, 0, 0) - 1;
/* Check and adjust input parameters. */
if (off > size)
return -EINVAL;
if (count > size - off)
count = size - off;
if (count) {
/* Get a copy of the hvc and copy out the relevant portion. */
char *hvc;
size = off + count;
hvc = kmalloc(size, GFP_KERNEL);
if (hvc == NULL)
return -ENOMEM;
hv_confstr(HV_CONFSTR_HV_CONFIG, (unsigned long)hvc, size);
memcpy(buf, hvc + off, count);
kfree(hvc);
}
return count;
}
static ssize_t hv_stats_show(struct device *dev,
struct device_attribute *attr,
char *page)
{
int cpu = dev->id;
long lotar = HV_XY_TO_LOTAR(cpu_x(cpu), cpu_y(cpu));
ssize_t n = hv_confstr(HV_CONFSTR_HV_STATS,
(unsigned long)page, PAGE_SIZE - 1,
lotar, 0);
n = n < 0 ? 0 : min(n, (ssize_t)PAGE_SIZE - 1);
page[n] = '\0';
return n;
}
static ssize_t hv_stats_store(struct device *dev,
struct device_attribute *attr,
const char *page,
size_t count)
{
int cpu = dev->id;
long lotar = HV_XY_TO_LOTAR(cpu_x(cpu), cpu_y(cpu));
ssize_t n = hv_confstr(HV_CONFSTR_HV_STATS, 0, 0, lotar, 1);
return n < 0 ? n : count;
}
static DEVICE_ATTR(hv_stats, 0644, hv_stats_show, hv_stats_store);
static int hv_stats_device_add(struct device *dev, struct subsys_interface *sif)
{
int err, cpu = dev->id;
if (!cpu_online(cpu))
return 0;
err = sysfs_create_file(&dev->kobj, &dev_attr_hv_stats.attr);
return err;
}
static int hv_stats_device_remove(struct device *dev,
struct subsys_interface *sif)
{
int cpu = dev->id;
if (!cpu_online(cpu))
return 0;
sysfs_remove_file(&dev->kobj, &dev_attr_hv_stats.attr);
return 0;
}
static struct subsys_interface hv_stats_interface = {
.name = "hv_stats",
.subsys = &cpu_subsys,
.add_dev = hv_stats_device_add,
.remove_dev = hv_stats_device_remove,
};
static int __init create_sysfs_entries(void)
{
int err = 0;
#define create_cpu_attr(name) \
if (!err) \
err = device_create_file(cpu_subsys.dev_root, &dev_attr_##name);
create_cpu_attr(chip_width);
create_cpu_attr(chip_height);
create_cpu_attr(chip_serial);
create_cpu_attr(chip_revision);
#define create_hv_attr(name) \
if (!err) \
err = sysfs_create_file(hypervisor_kobj, &dev_attr_##name.attr);
create_hv_attr(type);
create_hv_attr(version);
create_hv_attr(config_version);
if (!err)
err = sysfs_create_group(hypervisor_kobj, &board_attr_group);
if (!err) {
sysfs_bin_attr_init(&hvconfig_bin);
hvconfig_bin.attr.name = "hvconfig";
hvconfig_bin.attr.mode = S_IRUGO;
hvconfig_bin.read = hvconfig_bin_read;
hvconfig_bin.size = PAGE_SIZE;
err = sysfs_create_bin_file(hypervisor_kobj, &hvconfig_bin);
}
if (!err) {
/*
* Don't bother adding the hv_stats files on each CPU if
* our hypervisor doesn't supply statistics.
*/
int cpu = raw_smp_processor_id();
long lotar = HV_XY_TO_LOTAR(cpu_x(cpu), cpu_y(cpu));
char dummy;
ssize_t n = hv_confstr(HV_CONFSTR_HV_STATS,
(unsigned long) &dummy, 1,
lotar, 0);
if (n >= 0)
err = subsys_interface_register(&hv_stats_interface);
}
return err;
}
subsys_initcall(create_sysfs_entries);