[PATCH 5/6] hwmon: amd_energy: dump energy counters via debugfs

Naveen Krishna Chatradhi
2020-09-05T14:33:07Z

Use seq_printf to capture the core and socket energies under debugfs
path in '/sys/kernel/debug/amd_energy/'
file cenergy_dump: To print out the core energy counters
file senergy_dump: To print out the socket energy counters

Signed-off-by: Naveen Krishna Chatradhi <nchatrad@amd.com>
---
drivers/hwmon/amd_energy.c | 110 +++++++++++++++++++++++++++++++++++++
1 file changed, 110 insertions(+)

diff --git a/drivers/hwmon/amd_energy.c b/drivers/hwmon/amd_energy.c
index c294bea56c02..2184bd4510ed 100644
--- a/drivers/hwmon/amd_energy.c
+++ b/drivers/hwmon/amd_energy.c
@@ -8,6 +8,7 @@
#include <linux/bits.h>
#include <linux/cpu.h>
#include <linux/cpumask.h>
+#include <linux/debugfs.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/hwmon.h>
@@ -20,6 +21,7 @@
#include <linux/platform_device.h>
#include <linux/sched.h>
#include <linux/slab.h>
+#include <linux/smp.h>
#include <linux/topology.h>
#include <linux/types.h>

@@ -57,6 +59,8 @@ struct amd_energy_data {
int nr_socks;
int core_id;
char (*label)[10];
+ u64 *cdump;
+ u64 *sdump;
};

static int amd_energy_read_labels(struct device *dev,
@@ -329,6 +333,108 @@ static int create_accumulate_status_file(struct amd_energy_data *data)
&accumulate_attr.attr);
}

+#ifdef CONFIG_DEBUG_FS
+static void dump_on_each_cpu(void *info)
+{
+ struct amd_energy_data *data = info;
+ int cpu = smp_processor_id();
+
+ amd_add_delta(data, cpu, cpu, (long *)&data->cdump[cpu],
+ ENERGY_CORE_MSR);
+}
+
+static int cenergy_dump_show(struct seq_file *s, void *unused)
+{
+ struct amd_energy_data *data = s->private;
+ struct cpumask *cpus_mask;
+ int i;
+
+ cpus_mask = kmalloc(sizeof(*cpus_mask), GFP_KERNEL);
+ memset(data->cdump, 0, (data->nr_cpus) * sizeof(u64));
+ cpumask_clear(cpus_mask);
+ for (i = 0; i < data->nr_cpus; i++) {
+ if (cpu_online(i))
+ cpumask_set_cpu(i, cpus_mask);
+ }
+
+ on_each_cpu_mask(cpus_mask, dump_on_each_cpu, data, true);
+
+ for (i = 0; i < data->nr_cpus; i++) {
+ if (!(i & 3))
+ seq_printf(s, "Core %3d: ", i);
+
+ seq_printf(s, "%16llu ", data->cdump[i]);
+ if ((i & 3) == 3)
+ seq_puts(s, "\n");
+ }
+ seq_puts(s, "\n");
+
+ kfree(cpus_mask);
+ return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(cenergy_dump);
+
+static int senergy_dump_show(struct seq_file *s, void *unused)
+{
+ struct amd_energy_data *data = s->private;
+ int i, cpu;
+
+ for (i = 0; i < data->nr_socks; i++) {
+ cpu = cpumask_first_and(cpu_online_mask,
+ cpumask_of_node(i));
+ amd_add_delta(data, data->nr_cpus + i, cpu,
+ (long *)&data->sdump[i], ENERGY_PKG_MSR);
+ seq_printf(s, "Socket %1d: %16llu\n",
+ i, data->sdump[i]);
+ }
+
+ return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(senergy_dump);
+
+static void dump_debugfs_cleanup(void *ddir)
+{
+ debugfs_remove_recursive(ddir);
+}
+
+static int create_dump_file(struct device *dev,
+ struct amd_energy_data *data)
+{
+ struct dentry *debugfs;
+ char name[] = "amd_energy";
+
+ data->cdump = devm_kcalloc(dev, data->nr_cpus,
+ sizeof(u64), GFP_KERNEL);
+ if (!data->cdump)
+ return -ENOMEM;
+
+ data->sdump = devm_kcalloc(dev, data->nr_socks,
+ sizeof(u64), GFP_KERNEL);
+ if (!data->sdump)
+ return -ENOMEM;
+
+ debugfs = debugfs_create_dir(name, NULL);
+ if (debugfs) {
+ debugfs_create_file("cenergy_dump", 0440,
+ debugfs, data, &cenergy_dump_fops);
+ debugfs_create_file("senergy_dump", 0440,
+ debugfs, data, &senergy_dump_fops);
+ devm_add_action_or_reset(data->hwmon_dev,
+ dump_debugfs_cleanup, debugfs);
+ }
+
+ return 0;
+}
+#else
+
+static int create_dump_file(struct device *dev,
+ struct amd_energy_data *data)
+{
+ return 0;
+}
+
+#endif //CONFIG_DEBUG_FS
+
static int amd_energy_probe(struct platform_device *pdev)
{
struct amd_energy_data *data;
@@ -376,6 +482,10 @@ static int amd_energy_probe(struct platform_device *pdev)
if (ret)
return ret;

+ ret = create_dump_file(dev, data);
+ if (ret)
+ return ret;
+
return 0;
}

--
2.26.2