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, 258 insertions, 0 deletions

diff --git a/drivers/pps/clients/pps-gpio.c b/drivers/pps/clients/pps-gpio.c
new file mode 100644
index 000000000..402f910f3
--- /dev/null
+++ b/drivers/pps/clients/pps-gpio.c
@@ -0,0 +1,258 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * pps-gpio.c -- PPS client driver using GPIO
+ *
+ * Copyright (C) 2010 Ricardo Martins <rasm@fe.up.pt>
+ * Copyright (C) 2011 James Nuss <jamesnuss@nanometrics.ca>
+ */
+
+#define PPS_GPIO_NAME "pps-gpio"
+#define pr_fmt(fmt) PPS_GPIO_NAME ": " fmt
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/pps_kernel.h>
+#include <linux/gpio/consumer.h>
+#include <linux/list.h>
+#include <linux/property.h>
+#include <linux/timer.h>
+#include <linux/jiffies.h>
+
+/* Info for each registered platform device */
+struct pps_gpio_device_data {
+	int irq;			/* IRQ used as PPS source */
+	struct pps_device *pps;		/* PPS source device */
+	struct pps_source_info info;	/* PPS source information */
+	struct gpio_desc *gpio_pin;	/* GPIO port descriptors */
+	struct gpio_desc *echo_pin;
+	struct timer_list echo_timer;	/* timer to reset echo active state */
+	bool assert_falling_edge;
+	bool capture_clear;
+	unsigned int echo_active_ms;	/* PPS echo active duration */
+	unsigned long echo_timeout;	/* timer timeout value in jiffies */
+};
+
+/*
+ * Report the PPS event
+ */
+
+static irqreturn_t pps_gpio_irq_handler(int irq, void *data)
+{
+	const struct pps_gpio_device_data *info;
+	struct pps_event_time ts;
+	int rising_edge;
+
+	/* Get the time stamp first */
+	pps_get_ts(&ts);
+
+	info = data;
+
+	/* Small trick to bypass the check on edge's direction when capture_clear is unset */
+	rising_edge = info->capture_clear ?
+		      gpiod_get_value(info->gpio_pin) : !info->assert_falling_edge;
+	if ((rising_edge && !info->assert_falling_edge) ||
+			(!rising_edge && info->assert_falling_edge))
+		pps_event(info->pps, &ts, PPS_CAPTUREASSERT, data);
+	else if (info->capture_clear &&
+			((rising_edge && info->assert_falling_edge) ||
+			(!rising_edge && !info->assert_falling_edge)))
+		pps_event(info->pps, &ts, PPS_CAPTURECLEAR, data);
+	else
+		dev_warn_ratelimited(&info->pps->dev, "IRQ did not trigger any PPS event\n");
+
+	return IRQ_HANDLED;
+}
+
+/* This function will only be called when an ECHO GPIO is defined */
+static void pps_gpio_echo(struct pps_device *pps, int event, void *data)
+{
+	/* add_timer() needs to write into info->echo_timer */
+	struct pps_gpio_device_data *info = data;
+
+	switch (event) {
+	case PPS_CAPTUREASSERT:
+		if (pps->params.mode & PPS_ECHOASSERT)
+			gpiod_set_value(info->echo_pin, 1);
+		break;
+
+	case PPS_CAPTURECLEAR:
+		if (pps->params.mode & PPS_ECHOCLEAR)
+			gpiod_set_value(info->echo_pin, 1);
+		break;
+	}
+
+	/* fire the timer */
+	if (info->pps->params.mode & (PPS_ECHOASSERT | PPS_ECHOCLEAR)) {
+		info->echo_timer.expires = jiffies + info->echo_timeout;
+		add_timer(&info->echo_timer);
+	}
+}
+
+/* Timer callback to reset the echo pin to the inactive state */
+static void pps_gpio_echo_timer_callback(struct timer_list *t)
+{
+	const struct pps_gpio_device_data *info;
+
+	info = timer_container_of(info, t, echo_timer);
+
+	gpiod_set_value(info->echo_pin, 0);
+}
+
+static int pps_gpio_setup(struct device *dev)
+{
+	struct pps_gpio_device_data *data = dev_get_drvdata(dev);
+	int ret;
+	u32 value;
+
+	data->gpio_pin = devm_gpiod_get(dev, NULL, GPIOD_IN);
+	if (IS_ERR(data->gpio_pin))
+		return dev_err_probe(dev, PTR_ERR(data->gpio_pin),
+				     "failed to request PPS GPIO\n");
+
+	data->assert_falling_edge =
+		device_property_read_bool(dev, "assert-falling-edge");
+
+	data->echo_pin = devm_gpiod_get_optional(dev, "echo", GPIOD_OUT_LOW);
+	if (IS_ERR(data->echo_pin))
+		return dev_err_probe(dev, PTR_ERR(data->echo_pin),
+				     "failed to request ECHO GPIO\n");
+
+	if (!data->echo_pin)
+		return 0;
+
+	ret = device_property_read_u32(dev, "echo-active-ms", &value);
+	if (ret) {
+		dev_err(dev, "failed to get echo-active-ms from FW\n");
+		return ret;
+	}
+
+	/* sanity check on echo_active_ms */
+	if (!value || value > 999) {
+		dev_err(dev, "echo-active-ms: %u - bad value from FW\n", value);
+		return -EINVAL;
+	}
+
+	data->echo_active_ms = value;
+
+	return 0;
+}
+
+static unsigned long
+get_irqf_trigger_flags(const struct pps_gpio_device_data *data)
+{
+	unsigned long flags = data->assert_falling_edge ?
+		IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING;
+
+	if (data->capture_clear) {
+		flags |= ((flags & IRQF_TRIGGER_RISING) ?
+				IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING);
+	}
+
+	return flags;
+}
+
+static int pps_gpio_probe(struct platform_device *pdev)
+{
+	struct pps_gpio_device_data *data;
+	struct device *dev = &pdev->dev;
+	int ret;
+	int pps_default_params;
+
+	/* allocate space for device info */
+	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	dev_set_drvdata(dev, data);
+
+	/* GPIO setup */
+	ret = pps_gpio_setup(dev);
+	if (ret)
+		return ret;
+
+	/* IRQ setup */
+	ret = gpiod_to_irq(data->gpio_pin);
+	if (ret < 0) {
+		dev_err(dev, "failed to map GPIO to IRQ: %d\n", ret);
+		return -EINVAL;
+	}
+	data->irq = ret;
+
+	/* initialize PPS specific parts of the bookkeeping data structure. */
+	data->info.mode = PPS_CAPTUREASSERT | PPS_OFFSETASSERT |
+		PPS_ECHOASSERT | PPS_CANWAIT | PPS_TSFMT_TSPEC;
+	if (data->capture_clear)
+		data->info.mode |= PPS_CAPTURECLEAR | PPS_OFFSETCLEAR |
+			PPS_ECHOCLEAR;
+	data->info.owner = THIS_MODULE;
+	snprintf(data->info.name, PPS_MAX_NAME_LEN - 1, "%s.%d",
+		 pdev->name, pdev->id);
+	if (data->echo_pin) {
+		data->info.echo = pps_gpio_echo;
+		data->echo_timeout = msecs_to_jiffies(data->echo_active_ms);
+		timer_setup(&data->echo_timer, pps_gpio_echo_timer_callback, 0);
+	}
+
+	/* register PPS source */
+	pps_default_params = PPS_CAPTUREASSERT | PPS_OFFSETASSERT;
+	if (data->capture_clear)
+		pps_default_params |= PPS_CAPTURECLEAR | PPS_OFFSETCLEAR;
+	data->pps = pps_register_source(&data->info, pps_default_params);
+	if (IS_ERR(data->pps)) {
+		dev_err(dev, "failed to register IRQ %d as PPS source\n",
+			data->irq);
+		return PTR_ERR(data->pps);
+	}
+
+	/* register IRQ interrupt handler */
+	ret = request_irq(data->irq, pps_gpio_irq_handler,
+			  get_irqf_trigger_flags(data), data->info.name, data);
+	if (ret) {
+		pps_unregister_source(data->pps);
+		dev_err(dev, "failed to acquire IRQ %d\n", data->irq);
+		return -EINVAL;
+	}
+
+	dev_dbg(&data->pps->dev, "Registered IRQ %d as PPS source\n",
+		data->irq);
+
+	return 0;
+}
+
+static void pps_gpio_remove(struct platform_device *pdev)
+{
+	struct pps_gpio_device_data *data = platform_get_drvdata(pdev);
+
+	free_irq(data->irq, data);
+	pps_unregister_source(data->pps);
+	timer_delete_sync(&data->echo_timer);
+	/* reset echo pin in any case */
+	gpiod_set_value(data->echo_pin, 0);
+	dev_info(&pdev->dev, "removed IRQ %d as PPS source\n", data->irq);
+}
+
+static const struct of_device_id pps_gpio_dt_ids[] = {
+	{ .compatible = "pps-gpio", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, pps_gpio_dt_ids);
+
+static struct platform_driver pps_gpio_driver = {
+	.probe		= pps_gpio_probe,
+	.remove		= pps_gpio_remove,
+	.driver		= {
+		.name	= PPS_GPIO_NAME,
+		.of_match_table	= pps_gpio_dt_ids,
+	},
+};
+
+module_platform_driver(pps_gpio_driver);
+MODULE_AUTHOR("Ricardo Martins <rasm@fe.up.pt>");
+MODULE_AUTHOR("James Nuss <jamesnuss@nanometrics.ca>");
+MODULE_DESCRIPTION("Use GPIO pin as PPS source");
+MODULE_LICENSE("GPL");
+MODULE_VERSION("1.2.0");