// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Hypervisor supplied "gpci" ("get performance counter info") performance
* counter support
*
* Author: Cody P Schafer <[email protected]>
* Copyright 2014 IBM Corporation.
*/
#define pr_fmt(fmt) "hv-gpci: " fmt
#include <linux/init.h>
#include <linux/perf_event.h>
#include <asm/firmware.h>
#include <asm/hvcall.h>
#include <asm/io.h>
#include "hv-gpci.h"
#include "hv-common.h"
/*
* Example usage:
* perf stat -e 'hv_gpci/counter_info_version=3,offset=0,length=8,
* secondary_index=0,starting_index=0xffffffff,request=0x10/' ...
*/
/* u32 */
EVENT_DEFINE_RANGE_FORMAT(request, config, 0, 31);
/* u32 */
/*
* Note that starting_index, phys_processor_idx, sibling_part_id,
* hw_chip_id, partition_id all refer to the same bit range. They
* are basically aliases for the starting_index. The specific alias
* used depends on the event. See REQUEST_IDX_KIND in hv-gpci-requests.h
*/
EVENT_DEFINE_RANGE_FORMAT(starting_index, config, 32, 63);
EVENT_DEFINE_RANGE_FORMAT_LITE(phys_processor_idx, config, 32, 63);
EVENT_DEFINE_RANGE_FORMAT_LITE(sibling_part_id, config, 32, 63);
EVENT_DEFINE_RANGE_FORMAT_LITE(hw_chip_id, config, 32, 63);
EVENT_DEFINE_RANGE_FORMAT_LITE(partition_id, config, 32, 63);
/* u16 */
EVENT_DEFINE_RANGE_FORMAT(secondary_index, config1, 0, 15);
/* u8 */
EVENT_DEFINE_RANGE_FORMAT(counter_info_version, config1, 16, 23);
/* u8, bytes of data (1-8) */
EVENT_DEFINE_RANGE_FORMAT(length, config1, 24, 31);
/* u32, byte offset */
EVENT_DEFINE_RANGE_FORMAT(offset, config1, 32, 63);
static cpumask_t hv_gpci_cpumask;
static struct attribute *format_attrs[] = {
&format_attr_request.attr,
&format_attr_starting_index.attr,
&format_attr_phys_processor_idx.attr,
&format_attr_sibling_part_id.attr,
&format_attr_hw_chip_id.attr,
&format_attr_partition_id.attr,
&format_attr_secondary_index.attr,
&format_attr_counter_info_version.attr,
&format_attr_offset.attr,
&format_attr_length.attr,
NULL,
};
static const struct attribute_group format_group = {
.name = "format",
.attrs = format_attrs,
};
static struct attribute_group event_group = {
.name = "events",
/* .attrs is set in init */
};
#define HV_CAPS_ATTR(_name, _format) \
static ssize_t _name##_show(struct device *dev, \
struct device_attribute *attr, \
char *page) \
{ \
struct hv_perf_caps caps; \
unsigned long hret = hv_perf_caps_get(&caps); \
if (hret) \
return -EIO; \
\
return sprintf(page, _format, caps._name); \
} \
static struct device_attribute hv_caps_attr_##_name = __ATTR_RO(_name)
static ssize_t kernel_version_show(struct device *dev,
struct device_attribute *attr,
char *page)
{
return sprintf(page, "0x%x\n", COUNTER_INFO_VERSION_CURRENT);
}
static ssize_t cpumask_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return cpumap_print_to_pagebuf(true, buf, &hv_gpci_cpumask);
}
/* Interface attribute array index to store system information */
#define INTERFACE_PROCESSOR_BUS_TOPOLOGY_ATTR 6
#define INTERFACE_PROCESSOR_CONFIG_ATTR 7
#define INTERFACE_AFFINITY_DOMAIN_VIA_VP_ATTR 8
#define INTERFACE_AFFINITY_DOMAIN_VIA_DOM_ATTR 9
#define INTERFACE_AFFINITY_DOMAIN_VIA_PAR_ATTR 10
#define INTERFACE_NULL_ATTR 11
/* Counter request value to retrieve system information */
enum {
PROCESSOR_BUS_TOPOLOGY,
PROCESSOR_CONFIG,
AFFINITY_DOMAIN_VIA_VP, /* affinity domain via virtual processor */
AFFINITY_DOMAIN_VIA_DOM, /* affinity domain via domain */
AFFINITY_DOMAIN_VIA_PAR, /* affinity domain via partition */
};
static int sysinfo_counter_request[] = {
[PROCESSOR_BUS_TOPOLOGY] = 0xD0,
[PROCESSOR_CONFIG] = 0x90,
[AFFINITY_DOMAIN_VIA_VP] = 0xA0,
[AFFINITY_DOMAIN_VIA_DOM] = 0xB0,
[AFFINITY_DOMAIN_VIA_PAR] = 0xB1,
};
static DEFINE_PER_CPU(char, hv_gpci_reqb[HGPCI_REQ_BUFFER_SIZE]) __aligned(sizeof(uint64_t));
static unsigned long systeminfo_gpci_request(u32 req, u32 starting_index,
u16 secondary_index, char *buf,
size_t *n, struct hv_gpci_request_buffer *arg)
{
unsigned long ret;
size_t i, j;
arg->params.counter_request = cpu_to_be32(req);
arg->params.starting_index = cpu_to_be32(starting_index);
arg->params.secondary_index = cpu_to_be16(secondary_index);
ret = plpar_hcall_norets(H_GET_PERF_COUNTER_INFO,
virt_to_phys(arg), HGPCI_REQ_BUFFER_SIZE);
/*
* ret value as 'H_PARAMETER' corresponds to 'GEN_BUF_TOO_SMALL',
* which means that the current buffer size cannot accommodate
* all the information and a partial buffer returned.
* hcall fails incase of ret value other than H_SUCCESS or H_PARAMETER.
*
* ret value as H_AUTHORITY implies that partition is not permitted to retrieve
* performance information, and required to set
* "Enable Performance Information Collection" option.
*/
if (ret == H_AUTHORITY)
return -EPERM;
/*
* hcall can fail with other possible ret value like H_PRIVILEGE/H_HARDWARE
* because of invalid buffer-length/address or due to some hardware
* error.
*/
if (ret && (ret != H_PARAMETER))
return -EIO;
/*
* hcall H_GET_PERF_COUNTER_INFO populates the 'returned_values'
* to show the total number of counter_value array elements
* returned via hcall.
* hcall also populates 'cv_element_size' corresponds to individual
* counter_value array element size. Below loop go through all
* counter_value array elements as per their size and add it to
* the output buffer.
*/
for (i = 0; i < be16_to_cpu(arg->params.returned_values); i++) {
j = i * be16_to_cpu(arg->params.cv_element_size);
for (; j < (i + 1) * be16_to_cpu(arg->params.cv_element_size); j++)
*n += sprintf(buf + *n, "%02x", (u8)arg->bytes[j]);
*n += sprintf(buf + *n, "\n");
}
if (*n >= PAGE_SIZE) {
pr_info("System information exceeds PAGE_SIZE\n");
return -EFBIG;
}
return ret;
}
static ssize_t processor_bus_topology_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct hv_gpci_request_buffer *arg;
unsigned long ret;
size_t n = 0;
arg = (void *)get_cpu_var(hv_gpci_reqb);
memset(arg, 0, HGPCI_REQ_BUFFER_SIZE);
/*
* Pass the counter request value 0xD0 corresponds to request
* type 'Processor_bus_topology', to retrieve
* the system topology information.
* starting_index value implies the starting hardware
* chip id.
*/
ret = systeminfo_gpci_request(sysinfo_counter_request[PROCESSOR_BUS_TOPOLOGY],
0, 0, buf, &n, arg);
if (!ret)
return n;
if (ret != H_PARAMETER)
goto out;
/*
* ret value as 'H_PARAMETER' corresponds to 'GEN_BUF_TOO_SMALL', which
* implies that buffer can't accommodate all information, and a partial buffer
* returned. To handle that, we need to make subsequent requests
* with next starting index to retrieve additional (missing) data.
* Below loop do subsequent hcalls with next starting index and add it
* to buffer util we get all the information.
*/
while (ret == H_PARAMETER) {
int returned_values = be16_to_cpu(arg->params.returned_values);
int elementsize = be16_to_cpu(arg->params.cv_element_size);
int last_element = (returned_values - 1) * elementsize;
/*
* Since the starting index value is part of counter_value
* buffer elements, use the starting index value in the last
* element and add 1 to make subsequent hcalls.
*/
u32 starting_index = arg->bytes[last_element + 3] +
(arg->bytes[last_element + 2] << 8) +
(arg->bytes[last_element + 1] << 16) +
(arg->bytes[last_element] << 24) + 1;
memset(arg, 0, HGPCI_REQ_BUFFER_SIZE);
ret = systeminfo_gpci_request(sysinfo_counter_request[PROCESSOR_BUS_TOPOLOGY],
starting_index, 0, buf, &n, arg);
if (!ret)
return n;
if (ret != H_PARAMETER)
goto out;
}
return n;
out:
put_cpu_var(hv_gpci_reqb);
return ret;
}
static ssize_t processor_config_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct hv_gpci_request_buffer *arg;
unsigned long ret;
size_t n = 0;
arg = (void *)get_cpu_var(hv_gpci_reqb);
memset(arg, 0, HGPCI_REQ_BUFFER_SIZE);
/*
* Pass the counter request value 0x90 corresponds to request
* type 'Processor_config', to retrieve
* the system processor information.
* starting_index value implies the starting hardware
* processor index.
*/
ret = systeminfo_gpci_request(sysinfo_counter_request[PROCESSOR_CONFIG],
0, 0, buf, &n, arg);
if (!ret)
return n;
if (ret != H_PARAMETER)
goto out;
/*
* ret value as 'H_PARAMETER' corresponds to 'GEN_BUF_TOO_SMALL', which
* implies that buffer can't accommodate all information, and a partial buffer
* returned. To handle that, we need to take subsequent requests
* with next starting index to retrieve additional (missing) data.
* Below loop do subsequent hcalls with next starting index and add it
* to buffer util we get all the information.
*/
while (ret == H_PARAMETER) {
int returned_values = be16_to_cpu(arg->params.returned_values);
int elementsize = be16_to_cpu(arg->params.cv_element_size);
int last_element = (returned_values - 1) * elementsize;
/*
* Since the starting index is part of counter_value
* buffer elements, use the starting index value in the last
* element and add 1 to subsequent hcalls.
*/
u32 starting_index = arg->bytes[last_element + 3] +
(arg->bytes[last_element + 2] << 8) +
(arg->bytes[last_element + 1] << 16) +
(arg->bytes[last_element] << 24) + 1;
memset(arg, 0, HGPCI_REQ_BUFFER_SIZE);
ret = systeminfo_gpci_request(sysinfo_counter_request[PROCESSOR_CONFIG],
starting_index, 0, buf, &n, arg);
if (!ret)
return n;
if (ret != H_PARAMETER)
goto out;
}
return n;
out:
put_cpu_var(hv_gpci_reqb);
return ret;
}
static ssize_t affinity_domain_via_virtual_processor_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct hv_gpci_request_buffer *arg;
unsigned long ret;
size_t n = 0;
arg = (void *)get_cpu_var(hv_gpci_reqb);
memset(arg, 0, HGPCI_REQ_BUFFER_SIZE);
/*
* Pass the counter request 0xA0 corresponds to request
* type 'Affinity_domain_information_by_virutal_processor',
* to retrieve the system affinity domain information.
* starting_index value refers to the starting hardware
* processor index.
*/
ret = systeminfo_gpci_request(sysinfo_counter_request[AFFINITY_DOMAIN_VIA_VP],
0, 0, buf, &n, arg);
if (!ret)
return n;
if (ret != H_PARAMETER)
goto out;
/*
* ret value as 'H_PARAMETER' corresponds to 'GEN_BUF_TOO_SMALL', which
* implies that buffer can't accommodate all information, and a partial buffer
* returned. To handle that, we need to take subsequent requests
* with next secondary index to retrieve additional (missing) data.
* Below loop do subsequent hcalls with next secondary index and add it
* to buffer util we get all the information.
*/
while (ret == H_PARAMETER) {
int returned_values = be16_to_cpu(arg->params.returned_values);
int elementsize = be16_to_cpu(arg->params.cv_element_size);
int last_element = (returned_values - 1) * elementsize;
/*
* Since the starting index and secondary index type is part of the
* counter_value buffer elements, use the starting index value in the
* last array element as subsequent starting index, and use secondary index
* value in the last array element plus 1 as subsequent secondary index.
* For counter request '0xA0', starting index points to partition id
* and secondary index points to corresponding virtual processor index.
*/
u32 starting_index = arg->bytes[last_element + 1] + (arg->bytes[last_element] << 8);
u16 secondary_index = arg->bytes[last_element + 3] +
(arg->bytes[last_element + 2] << 8) + 1;
memset(arg, 0, HGPCI_REQ_BUFFER_SIZE);
ret = systeminfo_gpci_request(sysinfo_counter_request[AFFINITY_DOMAIN_VIA_VP],
starting_index, secondary_index, buf, &n, arg);
if (!ret)
return n;
if (ret != H_PARAMETER)
goto out;
}
return n;
out:
put_cpu_var(hv_gpci_reqb);
return ret;
}
static ssize_t affinity_domain_via_domain_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct hv_gpci_request_buffer *arg;
unsigned long ret;
size_t n = 0;
arg = (void *)get_cpu_var(hv_gpci_reqb);
memset(arg, 0, HGPCI_REQ_BUFFER_SIZE);
/*
* Pass the counter request 0xB0 corresponds to request
* type 'Affinity_domain_information_by_domain',
* to retrieve the system affinity domain information.
* starting_index value refers to the starting hardware
* processor index.
*/
ret = systeminfo_gpci_request(sysinfo_counter_request[AFFINITY_DOMAIN_VIA_DOM],
0, 0, buf, &n, arg);
if (!ret)
return n;
if (ret != H_PARAMETER)
goto out;
/*
* ret value as 'H_PARAMETER' corresponds to 'GEN_BUF_TOO_SMALL', which
* implies that buffer can't accommodate all information, and a partial buffer
* returned. To handle that, we need to take subsequent requests
* with next starting index to retrieve additional (missing) data.
* Below loop do subsequent hcalls with next starting index and add it
* to buffer util we get all the information.
*/
while (ret == H_PARAMETER) {
int returned_values = be16_to_cpu(arg->params.returned_values);
int elementsize = be16_to_cpu(arg->params.cv_element_size);
int last_element = (returned_values - 1) * elementsize;
/*
* Since the starting index value is part of counter_value
* buffer elements, use the starting index value in the last
* element and add 1 to make subsequent hcalls.
*/
u32 starting_index = arg->bytes[last_element + 1] +
(arg->bytes[last_element] << 8) + 1;
memset(arg, 0, HGPCI_REQ_BUFFER_SIZE);
ret = systeminfo_gpci_request(sysinfo_counter_request[AFFINITY_DOMAIN_VIA_DOM],
starting_index, 0, buf, &n, arg);
if (!ret)
return n;
if (ret != H_PARAMETER)
goto out;
}
return n;
out:
put_cpu_var(hv_gpci_reqb);
return ret;
}
static void affinity_domain_via_partition_result_parse(int returned_values,
int element_size, char *buf, size_t *last_element,
size_t *n, struct hv_gpci_request_buffer *arg)
{
size_t i = 0, j = 0;
size_t k, l, m;
uint16_t total_affinity_domain_ele, size_of_each_affinity_domain_ele;
/*
* hcall H_GET_PERF_COUNTER_INFO populates the 'returned_values'
* to show the total number of counter_value array elements
* returned via hcall.
* Unlike other request types, the data structure returned by this
* request is variable-size. For this counter request type,
* hcall populates 'cv_element_size' corresponds to minimum size of
* the structure returned i.e; the size of the structure with no domain
* information. Below loop go through all counter_value array
* to determine the number and size of each domain array element and
* add it to the output buffer.
*/
while (i < returned_values) {
k = j;
for (; k < j + element_size; k++)
*n += sprintf(buf + *n, "%02x", (u8)arg->bytes[k]);
*n += sprintf(buf + *n, "\n");
total_affinity_domain_ele = (u8)arg->bytes[k - 2] << 8 | (u8)arg->bytes[k - 3];
size_of_each_affinity_domain_ele = (u8)arg->bytes[k] << 8 | (u8)arg->bytes[k - 1];
for (l = 0; l < total_affinity_domain_ele; l++) {
for (m = 0; m < size_of_each_affinity_domain_ele; m++) {
*n += sprintf(buf + *n, "%02x", (u8)arg->bytes[k]);
k++;
}
*n += sprintf(buf + *n, "\n");
}
*n += sprintf(buf + *n, "\n");
i++;
j = k;
}
*last_element = k;
}
static ssize_t affinity_domain_via_partition_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct hv_gpci_request_buffer *arg;
unsigned long ret;
size_t n = 0;
size_t last_element = 0;
u32 starting_index;
arg = (void *)get_cpu_var(hv_gpci_reqb);
memset(arg, 0, HGPCI_REQ_BUFFER_SIZE);
/*
* Pass the counter request value 0xB1 corresponds to counter request
* type 'Affinity_domain_information_by_partition',
* to retrieve the system affinity domain by partition information.
* starting_index value refers to the starting hardware
* processor index.
*/
arg->params.counter_request = cpu_to_be32(sysinfo_counter_request[AFFINITY_DOMAIN_VIA_PAR]);
arg->params.starting_index = cpu_to_be32(0);
ret = plpar_hcall_norets(H_GET_PERF_COUNTER_INFO,
virt_to_phys(arg), HGPCI_REQ_BUFFER_SIZE);
if (!ret)
goto parse_result;
if (ret && (ret != H_PARAMETER))
goto out;
/*
* ret value as 'H_PARAMETER' implies that the current buffer size
* can't accommodate all the information, and a partial buffer
* returned. To handle that, we need to make subsequent requests
* with next starting index to retrieve additional (missing) data.
* Below loop do subsequent hcalls with next starting index and add it
* to buffer util we get all the information.
*/
while (ret == H_PARAMETER) {
affinity_domain_via_partition_result_parse(
be16_to_cpu(arg->params.returned_values) - 1,
be16_to_cpu(arg->params.cv_element_size), buf,
&last_element, &n, arg);
if (n >= PAGE_SIZE) {
put_cpu_var(hv_gpci_reqb);
pr_debug("System information exceeds PAGE_SIZE\n");
return -EFBIG;
}
/*
* Since the starting index value is part of counter_value
* buffer elements, use the starting_index value in the last
* element and add 1 to make subsequent hcalls.
*/
starting_index = (u8)arg->bytes[last_element] << 8 |
(u8)arg->bytes[last_element + 1];
memset(arg, 0, HGPCI_REQ_BUFFER_SIZE);
arg->params.counter_request = cpu_to_be32(
sysinfo_counter_request[AFFINITY_DOMAIN_VIA_PAR]);
arg->params.starting_index = cpu_to_be32(starting_index);
ret = plpar_hcall_norets(H_GET_PERF_COUNTER_INFO,
virt_to_phys(arg), HGPCI_REQ_BUFFER_SIZE);
if (ret && (ret != H_PARAMETER))
goto out;
}
parse_result:
affinity_domain_via_partition_result_parse(
be16_to_cpu(arg->params.returned_values),
be16_to_cpu(arg->params.cv_element_size),
buf, &last_element, &n, arg);
put_cpu_var(hv_gpci_reqb);
return n;
out:
put_cpu_var(hv_gpci_reqb);
/*
* ret value as 'H_PARAMETER' corresponds to 'GEN_BUF_TOO_SMALL',
* which means that the current buffer size cannot accommodate
* all the information and a partial buffer returned.
* hcall fails incase of ret value other than H_SUCCESS or H_PARAMETER.
*
* ret value as H_AUTHORITY implies that partition is not permitted to retrieve
* performance information, and required to set
* "Enable Performance Information Collection" option.
*/
if (ret == H_AUTHORITY)
return -EPERM;
/*
* hcall can fail with other possible ret value like H_PRIVILEGE/H_HARDWARE
* because of invalid buffer-length/address or due to some hardware
* error.
*/
return -EIO;
}
static DEVICE_ATTR_RO(kernel_version);
static DEVICE_ATTR_RO(cpumask);
HV_CAPS_ATTR(version, "0x%x\n");
HV_CAPS_ATTR(ga, "%d\n");
HV_CAPS_ATTR(expanded, "%d\n");
HV_CAPS_ATTR(lab, "%d\n");
HV_CAPS_ATTR(collect_privileged, "%d\n");
static struct attribute *interface_attrs[] = {
&dev_attr_kernel_version.attr,
&hv_caps_attr_version.attr,
&hv_caps_attr_ga.attr,
&hv_caps_attr_expanded.attr,
&hv_caps_attr_lab.attr,
&hv_caps_attr_collect_privileged.attr,
/*
* This NULL is a placeholder for the processor_bus_topology
* attribute, set in init function if applicable.
*/
NULL,
/*
* This NULL is a placeholder for the processor_config
* attribute, set in init function if applicable.
*/
NULL,
/*
* This NULL is a placeholder for the affinity_domain_via_virtual_processor
* attribute, set in init function if applicable.
*/
NULL,
/*
* This NULL is a placeholder for the affinity_domain_via_domain
* attribute, set in init function if applicable.
*/
NULL,
/*
* This NULL is a placeholder for the affinity_domain_via_partition
* attribute, set in init function if applicable.
*/
NULL,
NULL,
};
static struct attribute *cpumask_attrs[] = {
&dev_attr_cpumask.attr,
NULL,
};
static const struct attribute_group cpumask_attr_group = {
.attrs = cpumask_attrs,
};
static const struct attribute_group interface_group = {
.name = "interface",
.attrs = interface_attrs,
};
static const struct attribute_group *attr_groups[] = {
&format_group,
&event_group,
&interface_group,
&cpumask_attr_group,
NULL,
};
static unsigned long single_gpci_request(u32 req, u32 starting_index,
u16 secondary_index, u8 version_in, u32 offset, u8 length,
u64 *value)
{
unsigned long ret;
size_t i;
u64 count;
struct hv_gpci_request_buffer *arg;
arg = (void *)get_cpu_var(hv_gpci_reqb);
memset(arg, 0, HGPCI_REQ_BUFFER_SIZE);
arg->params.counter_request = cpu_to_be32(req);
arg->params.starting_index = cpu_to_be32(starting_index);
arg->params.secondary_index = cpu_to_be16(secondary_index);
arg->params.counter_info_version_in = version_in;
ret = plpar_hcall_norets(H_GET_PERF_COUNTER_INFO,
virt_to_phys(arg), HGPCI_REQ_BUFFER_SIZE);
/*
* ret value as 'H_PARAMETER' with detail_rc as 'GEN_BUF_TOO_SMALL',
* specifies that the current buffer size cannot accommodate
* all the information and a partial buffer returned.
* Since in this function we are only accessing data for a given starting index,
* we don't need to accommodate whole data and can get required count by
* accessing first entry data.
* Hence hcall fails only incase the ret value is other than H_SUCCESS or
* H_PARAMETER with detail_rc value as GEN_BUF_TOO_SMALL(0x1B).
*/
if (ret == H_PARAMETER && be32_to_cpu(arg->params.detail_rc) == 0x1B)
ret = 0;
if (ret) {
pr_devel("hcall failed: 0x%lx\n", ret);
goto out;
}
/*
* we verify offset and length are within the zeroed buffer at event
* init.
*/
count = 0;
for (i = offset; i < offset + length; i++)
count |= (u64)(arg->bytes[i]) << ((length - 1 - (i - offset)) * 8);
*value = count;
out:
put_cpu_var(hv_gpci_reqb);
return ret;
}
static u64 h_gpci_get_value(struct perf_event *event)
{
u64 count;
unsigned long ret = single_gpci_request(event_get_request(event),
event_get_starting_index(event),
event_get_secondary_index(event),
event_get_counter_info_version(event),
event_get_offset(event),
event_get_length(event),
&count);
if (ret)
return 0;
return count;
}
static void h_gpci_event_update(struct perf_event *event)
{
s64 prev;
u64 now = h_gpci_get_value(event);
prev = local64_xchg(&event->hw.prev_count, now);
local64_add(now - prev, &event->count);
}
static void h_gpci_event_start(struct perf_event *event, int flags)
{
local64_set(&event->hw.prev_count, h_gpci_get_value(event));
}
static void h_gpci_event_stop(struct perf_event *event, int flags)
{
h_gpci_event_update(event);
}
static int h_gpci_event_add(struct perf_event *event, int flags)
{
if (flags & PERF_EF_START)
h_gpci_event_start(event, flags);
return 0;
}
static int h_gpci_event_init(struct perf_event *event)
{
u64 count;
u8 length;
unsigned long ret;
/* Not our event */
if (event->attr.type != event->pmu->type)
return -ENOENT;
/* config2 is unused */
if (event->attr.config2) {
pr_devel("config2 set when reserved\n");
return -EINVAL;
}
/* no branch sampling */
if (has_branch_stack(event))
return -EOPNOTSUPP;
length = event_get_length(event);
if (length < 1 || length > 8) {
pr_devel("length invalid\n");
return -EINVAL;
}
/* last byte within the buffer? */
if ((event_get_offset(event) + length) > HGPCI_MAX_DATA_BYTES) {
pr_devel("request outside of buffer: %zu > %zu\n",
(size_t)event_get_offset(event) + length,
HGPCI_MAX_DATA_BYTES);
return -EINVAL;
}
/* check if the request works... */
ret = single_gpci_request(event_get_request(event),
event_get_starting_index(event),
event_get_secondary_index(event),
event_get_counter_info_version(event),
event_get_offset(event),
length,
&count);
/*
* ret value as H_AUTHORITY implies that partition is not permitted to retrieve
* performance information, and required to set
* "Enable Performance Information Collection" option.
*/
if (ret == H_AUTHORITY)
return -EPERM;
if (ret) {
pr_devel("gpci hcall failed\n");
return -EINVAL;
}
return 0;
}
static struct pmu h_gpci_pmu = {
.task_ctx_nr = perf_invalid_context,
.name = "hv_gpci",
.attr_groups = attr_groups,
.event_init = h_gpci_event_init,
.add = h_gpci_event_add,
.del = h_gpci_event_stop,
.start = h_gpci_event_start,
.stop = h_gpci_event_stop,
.read = h_gpci_event_update,
.capabilities = PERF_PMU_CAP_NO_EXCLUDE,
};
static int ppc_hv_gpci_cpu_online(unsigned int cpu)
{
if (cpumask_empty(&hv_gpci_cpumask))
cpumask_set_cpu(cpu, &hv_gpci_cpumask);
return 0;
}
static int ppc_hv_gpci_cpu_offline(unsigned int cpu)
{
int target;
/* Check if exiting cpu is used for collecting gpci events */
if (!cpumask_test_and_clear_cpu(cpu, &hv_gpci_cpumask))
return 0;
/* Find a new cpu to collect gpci events */
target = cpumask_last(cpu_active_mask);
if (target < 0 || target >= nr_cpu_ids) {
pr_err("hv_gpci: CPU hotplug init failed\n");
return -1;
}
/* Migrate gpci events to the new target */
cpumask_set_cpu(target, &hv_gpci_cpumask);
perf_pmu_migrate_context(&h_gpci_pmu, cpu, target);
return 0;
}
static int hv_gpci_cpu_hotplug_init(void)
{
return cpuhp_setup_state(CPUHP_AP_PERF_POWERPC_HV_GPCI_ONLINE,
"perf/powerpc/hv_gcpi:online",
ppc_hv_gpci_cpu_online,
ppc_hv_gpci_cpu_offline);
}
static struct device_attribute *sysinfo_device_attr_create(int
sysinfo_interface_group_index, u32 req)
{
struct device_attribute *attr = NULL;
unsigned long ret;
struct hv_gpci_request_buffer *arg;
if (sysinfo_interface_group_index < INTERFACE_PROCESSOR_BUS_TOPOLOGY_ATTR ||
sysinfo_interface_group_index >= INTERFACE_NULL_ATTR) {
pr_info("Wrong interface group index for system information\n");
return NULL;
}
/* Check for given counter request value support */
arg = (void *)get_cpu_var(hv_gpci_reqb);
memset(arg, 0, HGPCI_REQ_BUFFER_SIZE);
arg->params.counter_request = cpu_to_be32(req);
ret = plpar_hcall_norets(H_GET_PERF_COUNTER_INFO,
virt_to_phys(arg), HGPCI_REQ_BUFFER_SIZE);
put_cpu_var(hv_gpci_reqb);
/*
* Add given counter request value attribute in the interface_attrs
* attribute array, only for valid return types.
*/
if (!ret || ret == H_AUTHORITY || ret == H_PARAMETER) {
attr = kzalloc(sizeof(*attr), GFP_KERNEL);
if (!attr)
return NULL;
sysfs_attr_init(&attr->attr);
attr->attr.mode = 0444;
switch (sysinfo_interface_group_index) {
case INTERFACE_PROCESSOR_BUS_TOPOLOGY_ATTR:
attr->attr.name = "processor_bus_topology";
attr->show = processor_bus_topology_show;
break;
case INTERFACE_PROCESSOR_CONFIG_ATTR:
attr->attr.name = "processor_config";
attr->show = processor_config_show;
break;
case INTERFACE_AFFINITY_DOMAIN_VIA_VP_ATTR:
attr->attr.name = "affinity_domain_via_virtual_processor";
attr->show = affinity_domain_via_virtual_processor_show;
break;
case INTERFACE_AFFINITY_DOMAIN_VIA_DOM_ATTR:
attr->attr.name = "affinity_domain_via_domain";
attr->show = affinity_domain_via_domain_show;
break;
case INTERFACE_AFFINITY_DOMAIN_VIA_PAR_ATTR:
attr->attr.name = "affinity_domain_via_partition";
attr->show = affinity_domain_via_partition_show;
break;
}
} else
pr_devel("hcall failed, with error: 0x%lx\n", ret);
return attr;
}
static void add_sysinfo_interface_files(void)
{
int sysfs_count;
struct device_attribute *attr[INTERFACE_NULL_ATTR - INTERFACE_PROCESSOR_BUS_TOPOLOGY_ATTR];
int i;
sysfs_count = INTERFACE_NULL_ATTR - INTERFACE_PROCESSOR_BUS_TOPOLOGY_ATTR;
/* Get device attribute for a given counter request value */
for (i = 0; i < sysfs_count; i++) {
attr[i] = sysinfo_device_attr_create(i + INTERFACE_PROCESSOR_BUS_TOPOLOGY_ATTR,
sysinfo_counter_request[i]);
if (!attr[i])
goto out;
}
/* Add sysinfo interface attributes in the interface_attrs attribute array */
for (i = 0; i < sysfs_count; i++)
interface_attrs[i + INTERFACE_PROCESSOR_BUS_TOPOLOGY_ATTR] = &attr[i]->attr;
return;
out:
/*
* The sysinfo interface attributes will be added, only if hcall passed for
* all the counter request values. Free the device attribute array incase
* of any hcall failure.
*/
if (i > 0) {
while (i >= 0) {
kfree(attr[i]);
i--;
}
}
}
static int hv_gpci_init(void)
{
int r;
unsigned long hret;
struct hv_perf_caps caps;
struct hv_gpci_request_buffer *arg;
hv_gpci_assert_offsets_correct();
if (!firmware_has_feature(FW_FEATURE_LPAR)) {
pr_debug("not a virtualized system, not enabling\n");
return -ENODEV;
}
hret = hv_perf_caps_get(&caps);
if (hret) {
pr_debug("could not obtain capabilities, not enabling, rc=%ld\n",
hret);
return -ENODEV;
}
/* init cpuhotplug */
r = hv_gpci_cpu_hotplug_init();
if (r)
return r;
/* sampling not supported */
h_gpci_pmu.capabilities |= PERF_PMU_CAP_NO_INTERRUPT;
arg = (void *)get_cpu_var(hv_gpci_reqb);
memset(arg, 0, HGPCI_REQ_BUFFER_SIZE);
/*
* hcall H_GET_PERF_COUNTER_INFO populates the output
* counter_info_version value based on the system hypervisor.
* Pass the counter request 0x10 corresponds to request type
* 'Dispatch_timebase_by_processor', to get the supported
* counter_info_version.
*/
arg->params.counter_request = cpu_to_be32(0x10);
r = plpar_hcall_norets(H_GET_PERF_COUNTER_INFO,
virt_to_phys(arg), HGPCI_REQ_BUFFER_SIZE);
if (r) {
pr_devel("hcall failed, can't get supported counter_info_version: 0x%x\n", r);
arg->params.counter_info_version_out = 0x8;
}
/*
* Use counter_info_version_out value to assign
* required hv-gpci event list.
*/
if (arg->params.counter_info_version_out >= 0x8)
event_group.attrs = hv_gpci_event_attrs;
else
event_group.attrs = hv_gpci_event_attrs_v6;
put_cpu_var(hv_gpci_reqb);
r = perf_pmu_register(&h_gpci_pmu, h_gpci_pmu.name, -1);
if (r)
return r;
/* sysinfo interface files are only available for power10 and above platforms */
if (PVR_VER(mfspr(SPRN_PVR)) >= PVR_POWER10)
add_sysinfo_interface_files();
return 0;
}
device_initcall(hv_gpci_init);
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