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powerpc/hv_gpci: Add sysfs file inside hv_gpci device to show affinity domain via domain information

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The hcall H_GET_PERF_COUNTER_INFO with counter request value as
AFFINITY_DOMAIN_INFORMATION_BY_DOMAIN(0XB0), can be used to get
the system affinity domain via domain information. To expose the system
affinity domain via domain information, patch adds sysfs file called
"affinity_domain_via_domain" to the "/sys/devices/hv_gpci/interface/"
of hv_gpci pmu driver.

Add new entry for AFFINITY_DOMAIN_VIA_DOM in sysinfo_counter_request
array, which points to the counter request value
"affinity_domain_via_domain" in hv-gpci.c file.

The affinity_domain_via_domain sysfs file is only available for power10
and above platforms. Add a macro called
INTERFACE_AFFINITY_DOMAIN_VIA_DOM_ATTR, which points to the index of NULL
placeholder, for affinity_domain_via_domain attribute in interface_attrs
array. Also updated the value of INTERFACE_NULL_ATTR macro in hv-gpci.c
file.

Reviewed-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230729073455.7918-8-kjain@linux.ibm.com
This commit is contained in:
Kajol Jain 2023-07-29 13:04:52 +05:30 committed by Michael Ellerman
parent cc89ff3491
commit a69a57cac1
1 changed files with 79 additions and 1 deletions
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80
arch/powerpc/perf/hv-gpci.c
View File

@ -106,19 +106,22 @@ static ssize_t cpumask_show(struct device *dev,
#define INTERFACE_PROCESSOR_BUS_TOPOLOGY_ATTR 6
#define INTERFACE_PROCESSOR_CONFIG_ATTR 7
#define INTERFACE_AFFINITY_DOMAIN_VIA_VP_ATTR 8
#define INTERFACE_NULL_ATTR 9
#define INTERFACE_AFFINITY_DOMAIN_VIA_DOM_ATTR 9
#define INTERFACE_NULL_ATTR 10
/* 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 */
};
static int sysinfo_counter_request[] = {
[PROCESSOR_BUS_TOPOLOGY] = 0xD0,
[PROCESSOR_CONFIG] = 0x90,
[AFFINITY_DOMAIN_VIA_VP] = 0xA0,
[AFFINITY_DOMAIN_VIA_DOM] = 0xB0,
};
static DEFINE_PER_CPU(char, hv_gpci_reqb[HGPCI_REQ_BUFFER_SIZE]) __aligned(sizeof(uint64_t));
@ -389,6 +392,72 @@ out:
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 DEVICE_ATTR_RO(kernel_version);
static DEVICE_ATTR_RO(cpumask);
@ -420,6 +489,11 @@ static struct attribute *interface_attrs[] = {
* 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,
NULL,
};
@ -674,6 +748,10 @@ static struct device_attribute *sysinfo_device_attr_create(int
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;
}
} else
pr_devel("hcall failed, with error: 0x%lx\n", ret);