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, 219 insertions, 0 deletions

diff --git a/drivers/leds/uleds.c b/drivers/leds/uleds.c
new file mode 100644
index 000000000..6affa581b
--- /dev/null
+++ b/drivers/leds/uleds.c
@@ -0,0 +1,219 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Userspace driver for the LED subsystem
+ *
+ * Copyright (C) 2016 David Lechner <david@lechnology.com>
+ *
+ * Based on uinput.c: Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org>
+ */
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/leds.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/poll.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+
+#include <uapi/linux/uleds.h>
+
+#define ULEDS_NAME	"uleds"
+
+enum uleds_state {
+	ULEDS_STATE_UNKNOWN,
+	ULEDS_STATE_REGISTERED,
+};
+
+struct uleds_device {
+	struct uleds_user_dev	user_dev;
+	struct led_classdev	led_cdev;
+	struct mutex		mutex;
+	enum uleds_state	state;
+	wait_queue_head_t	waitq;
+	int			brightness;
+	bool			new_data;
+};
+
+static struct miscdevice uleds_misc;
+
+static void uleds_brightness_set(struct led_classdev *led_cdev,
+				 enum led_brightness brightness)
+{
+	struct uleds_device *udev = container_of(led_cdev, struct uleds_device,
+						 led_cdev);
+
+	if (udev->brightness != brightness) {
+		udev->brightness = brightness;
+		udev->new_data = true;
+		wake_up_interruptible(&udev->waitq);
+	}
+}
+
+static int uleds_open(struct inode *inode, struct file *file)
+{
+	struct uleds_device *udev;
+
+	udev = kzalloc_obj(*udev);
+	if (!udev)
+		return -ENOMEM;
+
+	udev->led_cdev.name = udev->user_dev.name;
+	udev->led_cdev.brightness_set = uleds_brightness_set;
+
+	mutex_init(&udev->mutex);
+	init_waitqueue_head(&udev->waitq);
+	udev->state = ULEDS_STATE_UNKNOWN;
+
+	file->private_data = udev;
+	stream_open(inode, file);
+
+	return 0;
+}
+
+static ssize_t uleds_write(struct file *file, const char __user *buffer,
+			   size_t count, loff_t *ppos)
+{
+	struct uleds_device *udev = file->private_data;
+	const char *name;
+	int ret;
+
+	if (count == 0)
+		return 0;
+
+	ret = mutex_lock_interruptible(&udev->mutex);
+	if (ret)
+		return ret;
+
+	if (udev->state == ULEDS_STATE_REGISTERED) {
+		ret = -EBUSY;
+		goto out;
+	}
+
+	if (count != sizeof(struct uleds_user_dev)) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	if (copy_from_user(&udev->user_dev, buffer,
+			   sizeof(struct uleds_user_dev))) {
+		ret = -EFAULT;
+		goto out;
+	}
+
+	name = udev->user_dev.name;
+	if (!name[0] || !strcmp(name, ".") || !strcmp(name, "..") ||
+	    strnchr(name, sizeof(udev->user_dev.name), '/') ||
+	    !strnchr(name, sizeof(udev->user_dev.name), '\0')) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	if (udev->user_dev.max_brightness <= 0) {
+		ret = -EINVAL;
+		goto out;
+	}
+	udev->led_cdev.max_brightness = udev->user_dev.max_brightness;
+
+	ret = devm_led_classdev_register(uleds_misc.this_device,
+					 &udev->led_cdev);
+	if (ret < 0)
+		goto out;
+
+	udev->new_data = true;
+	udev->state = ULEDS_STATE_REGISTERED;
+	ret = count;
+
+out:
+	mutex_unlock(&udev->mutex);
+
+	return ret;
+}
+
+static ssize_t uleds_read(struct file *file, char __user *buffer, size_t count,
+			  loff_t *ppos)
+{
+	struct uleds_device *udev = file->private_data;
+	ssize_t retval;
+
+	if (count < sizeof(udev->brightness))
+		return 0;
+
+	do {
+		retval = mutex_lock_interruptible(&udev->mutex);
+		if (retval)
+			return retval;
+
+		if (udev->state != ULEDS_STATE_REGISTERED) {
+			retval = -ENODEV;
+		} else if (!udev->new_data && (file->f_flags & O_NONBLOCK)) {
+			retval = -EAGAIN;
+		} else if (udev->new_data) {
+			if (copy_to_user(buffer, &udev->brightness,
+					 sizeof(udev->brightness))) {
+				retval = -EFAULT;
+			} else {
+				udev->new_data = false;
+				retval = sizeof(udev->brightness);
+			}
+		}
+
+		mutex_unlock(&udev->mutex);
+
+		if (retval)
+			break;
+
+		if (!(file->f_flags & O_NONBLOCK))
+			retval = wait_event_interruptible(udev->waitq,
+					udev->new_data ||
+					udev->state != ULEDS_STATE_REGISTERED);
+	} while (retval == 0);
+
+	return retval;
+}
+
+static __poll_t uleds_poll(struct file *file, poll_table *wait)
+{
+	struct uleds_device *udev = file->private_data;
+
+	poll_wait(file, &udev->waitq, wait);
+
+	if (udev->new_data)
+		return EPOLLIN | EPOLLRDNORM;
+
+	return 0;
+}
+
+static int uleds_release(struct inode *inode, struct file *file)
+{
+	struct uleds_device *udev = file->private_data;
+
+	if (udev->state == ULEDS_STATE_REGISTERED) {
+		udev->state = ULEDS_STATE_UNKNOWN;
+		devm_led_classdev_unregister(uleds_misc.this_device,
+					     &udev->led_cdev);
+	}
+	kfree(udev);
+
+	return 0;
+}
+
+static const struct file_operations uleds_fops = {
+	.owner		= THIS_MODULE,
+	.open		= uleds_open,
+	.release	= uleds_release,
+	.read		= uleds_read,
+	.write		= uleds_write,
+	.poll		= uleds_poll,
+};
+
+static struct miscdevice uleds_misc = {
+	.fops		= &uleds_fops,
+	.minor		= MISC_DYNAMIC_MINOR,
+	.name		= ULEDS_NAME,
+};
+
+module_misc_device(uleds_misc);
+
+MODULE_AUTHOR("David Lechner <david@lechnology.com>");
+MODULE_DESCRIPTION("Userspace driver for the LED subsystem");
+MODULE_LICENSE("GPL");