The hcall H_GET_PERF_COUNTER_INFO with counter request value as
PROCESSOR_CONFIG(0X90), can be used to get the system
processor configuration information. To expose the system
processor config information, patch adds sysfs file called
"processor_config" to the "/sys/devices/hv_gpci/interface/"
of hv_gpci pmu driver.
Add enum and sysinfo_counter_request array to get required
counter request value in hv-gpci.c file.
Also add a new function called "sysinfo_device_attr_create",
which will create and return required device attribute to the
add_sysinfo_interface_files function.
The processor_config sysfs file is only available for power10
and above platforms. Add a new macro called
INTERFACE_PROCESSOR_CONFIG_ATTR, which points to the index of
NULL placefolder, for processor_config attribute in the interface_attrs
array. Also add macro INTERFACE_NULL_ATTR which points to index of NULL
attribute in interface_attrs array.
Signed-off-by: Kajol Jain <kj...@linux.ibm.com>
---
arch/powerpc/perf/hv-gpci.c | 168 ++++++++++++++++++++++++++++++++----
1 file changed, 153 insertions(+), 15 deletions(-)
diff --git a/arch/powerpc/perf/hv-gpci.c b/arch/powerpc/perf/hv-gpci.c
index 225f148f75fd..c74076d3c7a7 100644
--- a/arch/powerpc/perf/hv-gpci.c
+++ b/arch/powerpc/perf/hv-gpci.c
@@ -102,11 +102,21 @@ static ssize_t cpumask_show(struct device *dev,
return cpumap_print_to_pagebuf(true, buf, &hv_gpci_cpumask);
}
-/* Counter request value to retrieve system information */
-#define PROCESSOR_BUS_TOPOLOGY 0XD0
-
/* Interface attribute array index to store system information */
#define INTERFACE_PROCESSOR_BUS_TOPOLOGY_ATTR 6
+#define INTERFACE_PROCESSOR_CONFIG_ATTR 7
+#define INTERFACE_NULL_ATTR 8
+
+/* Counter request value to retrieve system information */
+enum {
+ PROCESSOR_BUS_TOPOLOGY,
+ PROCESSOR_CONFIG
+};
+
+static int sysinfo_counter_request[] = {
+ [PROCESSOR_BUS_TOPOLOGY] = 0xD0,
+ [PROCESSOR_CONFIG] = 0x90,
+};
static DEFINE_PER_CPU(char, hv_gpci_reqb[HGPCI_REQ_BUFFER_SIZE])
__aligned(sizeof(uint64_t));
@@ -187,7 +197,8 @@ static ssize_t processor_bus_topology_show(struct device
*dev, struct device_att
* starting_index value implies the starting hardware
* chip id.
*/
- ret = systeminfo_gpci_request(PROCESSOR_BUS_TOPOLOGY, 0, 0, buf, &n,
arg);
+ ret =
systeminfo_gpci_request(sysinfo_counter_request[PROCESSOR_BUS_TOPOLOGY],
+ 0, 0, buf, &n, arg);
if (!ret)
return n;
@@ -220,8 +231,76 @@ static ssize_t processor_bus_topology_show(struct device
*dev, struct device_att
memset(arg, 0, HGPCI_REQ_BUFFER_SIZE);
- ret = systeminfo_gpci_request(PROCESSOR_BUS_TOPOLOGY,
starting_index,
- 0, buf, &n, arg);
+ 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;
@@ -258,6 +337,11 @@ static struct attribute *interface_attrs[] = {
* 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,
NULL,
};
@@ -463,17 +547,24 @@ static int hv_gpci_cpu_hotplug_init(void)
ppc_hv_gpci_cpu_offline);
}
-static void add_sysinfo_interface_files(void)
+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;
- /* Check for counter request type PROCESSOR_BUS_TOPOLOGY support */
+ 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(PROCESSOR_BUS_TOPOLOGY);
+ 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);
@@ -481,24 +572,71 @@ static void add_sysinfo_interface_files(void)
put_cpu_var(hv_gpci_reqb);
/*
- * Add processor_bus_topology attribute in the interface_attrs
+ * 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) {
- pr_info("Memory allocation failed for sysinfo interface
files\n");
- return;
+ pr_info("Mem allocation failed, for sysinfo interface
file");
+ return NULL;
}
sysfs_attr_init(&attr->attr);
- attr->attr.name = "processor_bug_topology";
attr->attr.mode = 0444;
- attr->show = processor_bus_topology_show;
- interface_attrs[INTERFACE_PROCESSOR_BUS_TOPOLOGY_ATTR] =
&attr->attr;
+
+ switch (sysinfo_interface_group_index) {
+ case INTERFACE_PROCESSOR_BUS_TOPOLOGY_ATTR:
+ attr->attr.name = "processor_bug_topology";
+ attr->show = processor_bus_topology_show;
+ break;
+ case INTERFACE_PROCESSOR_CONFIG_ATTR:
+ attr->attr.name = "processor_config";
+ attr->show = processor_config_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)
--
2.31.1
