scftorture: Count single_rpc offline failures in statistics outputgrafted

scf_torture_stats_print() aggregates each invoker thread's counters
into a local scf_statistics structure before printing, but the
n_single_rpc_ofl field is missing from the aggregation loop.  As a
result, the "single_rpc_ofl" value printed in the statistics line is
always zero, even when smp_call_function_single() invocations for the
RPC test have failed due to offline CPUs and been counted by the
invoker threads.

Add the missing accumulation so that the printed value reflects the
actual counts.

Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

1 files changed, 204 insertions, 0 deletions

diff --git a/drivers/misc/eeprom/max6875.c b/drivers/misc/eeprom/max6875.c
new file mode 100644
index 000000000..5731d2dc8
--- /dev/null
+++ b/drivers/misc/eeprom/max6875.c
@@ -0,0 +1,204 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * max6875.c - driver for MAX6874/MAX6875
+ *
+ * Copyright (C) 2005 Ben Gardner <bgardner@wabtec.com>
+ *
+ * Based on eeprom.c
+ *
+ * The MAX6875 has a bank of registers and two banks of EEPROM.
+ * Address ranges are defined as follows:
+ *  * 0x0000 - 0x0046 = configuration registers
+ *  * 0x8000 - 0x8046 = configuration EEPROM
+ *  * 0x8100 - 0x82FF = user EEPROM
+ *
+ * This driver makes the user EEPROM available for read.
+ *
+ * The registers & config EEPROM should be accessed via i2c-dev.
+ *
+ * The MAX6875 ignores the lowest address bit, so each chip responds to
+ * two addresses - 0x50/0x51 and 0x52/0x53.
+ *
+ * Note that the MAX6875 uses i2c_smbus_write_byte_data() to set the read
+ * address, so this driver is destructive if loaded for the wrong EEPROM chip.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/mutex.h>
+
+/* The MAX6875 can only read/write 16 bytes at a time */
+#define SLICE_SIZE			16
+#define SLICE_BITS			4
+
+/* USER EEPROM is at addresses 0x8100 - 0x82FF */
+#define USER_EEPROM_BASE		0x8100
+#define USER_EEPROM_SIZE		0x0200
+#define USER_EEPROM_SLICES		32
+
+/* MAX6875 commands */
+#define MAX6875_CMD_BLK_READ		0x84
+
+/* Each client has this additional data */
+struct max6875_data {
+	struct i2c_client	*fake_client;
+	struct mutex		update_lock;
+
+	u32			valid;
+	u8			data[USER_EEPROM_SIZE];
+	unsigned long		last_updated[USER_EEPROM_SLICES];
+};
+
+static void max6875_update_slice(struct i2c_client *client, int slice)
+{
+	struct max6875_data *data = i2c_get_clientdata(client);
+	int i, j, addr;
+	u8 *buf;
+
+	if (slice >= USER_EEPROM_SLICES)
+		return;
+
+	mutex_lock(&data->update_lock);
+
+	buf = &data->data[slice << SLICE_BITS];
+
+	if (!(data->valid & (1 << slice)) ||
+	    time_after(jiffies, data->last_updated[slice])) {
+
+		dev_dbg(&client->dev, "Starting update of slice %u\n", slice);
+
+		data->valid &= ~(1 << slice);
+
+		addr = USER_EEPROM_BASE + (slice << SLICE_BITS);
+
+		/* select the eeprom address */
+		if (i2c_smbus_write_byte_data(client, addr >> 8, addr & 0xFF)) {
+			dev_err(&client->dev, "address set failed\n");
+			goto exit_up;
+		}
+
+		if (i2c_check_functionality(client->adapter,
+					    I2C_FUNC_SMBUS_READ_I2C_BLOCK)) {
+			if (i2c_smbus_read_i2c_block_data(client,
+							  MAX6875_CMD_BLK_READ,
+							  SLICE_SIZE,
+							  buf) != SLICE_SIZE) {
+				goto exit_up;
+			}
+		} else {
+			for (i = 0; i < SLICE_SIZE; i++) {
+				j = i2c_smbus_read_byte(client);
+				if (j < 0) {
+					goto exit_up;
+				}
+				buf[i] = j;
+			}
+		}
+		data->last_updated[slice] = jiffies;
+		data->valid |= (1 << slice);
+	}
+exit_up:
+	mutex_unlock(&data->update_lock);
+}
+
+static ssize_t max6875_read(struct file *filp, struct kobject *kobj,
+			    const struct bin_attribute *bin_attr,
+			    char *buf, loff_t off, size_t count)
+{
+	struct i2c_client *client = kobj_to_i2c_client(kobj);
+	struct max6875_data *data = i2c_get_clientdata(client);
+	int slice, max_slice;
+
+	/* refresh slices which contain requested bytes */
+	max_slice = (off + count - 1) >> SLICE_BITS;
+	for (slice = (off >> SLICE_BITS); slice <= max_slice; slice++)
+		max6875_update_slice(client, slice);
+
+	memcpy(buf, &data->data[off], count);
+
+	return count;
+}
+
+static const struct bin_attribute user_eeprom_attr = {
+	.attr = {
+		.name = "eeprom",
+		.mode = S_IRUGO,
+	},
+	.size = USER_EEPROM_SIZE,
+	.read = max6875_read,
+};
+
+static int max6875_probe(struct i2c_client *client)
+{
+	struct i2c_adapter *adapter = client->adapter;
+	struct max6875_data *data;
+	int err;
+
+	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WRITE_BYTE_DATA
+				     | I2C_FUNC_SMBUS_READ_BYTE))
+		return -ENODEV;
+
+	/* Only bind to even addresses */
+	if (client->addr & 1)
+		return -ENODEV;
+
+	data = kzalloc_obj(struct max6875_data);
+	if (!data)
+		return -ENOMEM;
+
+	/* A fake client is created on the odd address */
+	data->fake_client = i2c_new_dummy_device(client->adapter, client->addr + 1);
+	if (IS_ERR(data->fake_client)) {
+		err = PTR_ERR(data->fake_client);
+		goto exit_kfree;
+	}
+
+	/* Init real i2c_client */
+	i2c_set_clientdata(client, data);
+	mutex_init(&data->update_lock);
+
+	err = sysfs_create_bin_file(&client->dev.kobj, &user_eeprom_attr);
+	if (err)
+		goto exit_remove_fake;
+
+	return 0;
+
+exit_remove_fake:
+	i2c_unregister_device(data->fake_client);
+exit_kfree:
+	kfree(data);
+	return err;
+}
+
+static void max6875_remove(struct i2c_client *client)
+{
+	struct max6875_data *data = i2c_get_clientdata(client);
+
+	i2c_unregister_device(data->fake_client);
+
+	sysfs_remove_bin_file(&client->dev.kobj, &user_eeprom_attr);
+	kfree(data);
+}
+
+static const struct i2c_device_id max6875_id[] = {
+	{ "max6875" },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, max6875_id);
+
+static struct i2c_driver max6875_driver = {
+	.driver = {
+		.name	= "max6875",
+	},
+	.probe		= max6875_probe,
+	.remove		= max6875_remove,
+	.id_table	= max6875_id,
+};
+
+module_i2c_driver(max6875_driver);
+
+MODULE_AUTHOR("Ben Gardner <bgardner@wabtec.com>");
+MODULE_DESCRIPTION("MAX6875 driver");
+MODULE_LICENSE("GPL");