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, 95 insertions, 0 deletions

diff --git a/drivers/cpufreq/raspberrypi-cpufreq.c b/drivers/cpufreq/raspberrypi-cpufreq.c
new file mode 100644
index 000000000..505093295
--- /dev/null
+++ b/drivers/cpufreq/raspberrypi-cpufreq.c
@@ -0,0 +1,95 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Raspberry Pi cpufreq driver
+ *
+ * Copyright (C) 2019, Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
+ */
+
+#include <linux/clk.h>
+#include <linux/cpu.h>
+#include <linux/cpufreq.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm_opp.h>
+
+#define RASPBERRYPI_FREQ_INTERVAL	100000000
+
+static struct platform_device *cpufreq_dt;
+
+static int raspberrypi_cpufreq_probe(struct platform_device *pdev)
+{
+	struct device *cpu_dev;
+	unsigned long min, max;
+	unsigned long rate;
+	struct clk *clk;
+	int ret;
+
+	cpu_dev = get_cpu_device(0);
+	if (!cpu_dev) {
+		pr_err("Cannot get CPU for cpufreq driver\n");
+		return -ENODEV;
+	}
+
+	clk = clk_get(cpu_dev, NULL);
+	if (IS_ERR(clk)) {
+		dev_err(cpu_dev, "Cannot get clock for CPU0\n");
+		return PTR_ERR(clk);
+	}
+
+	/*
+	 * The max and min frequencies are configurable in the Raspberry Pi
+	 * firmware, so we query them at runtime.
+	 */
+	min = roundup(clk_round_rate(clk, 0), RASPBERRYPI_FREQ_INTERVAL);
+	max = roundup(clk_round_rate(clk, ULONG_MAX), RASPBERRYPI_FREQ_INTERVAL);
+	clk_put(clk);
+
+	for (rate = min; rate <= max; rate += RASPBERRYPI_FREQ_INTERVAL) {
+		ret = dev_pm_opp_add(cpu_dev, rate, 0);
+		if (ret)
+			goto remove_opp;
+	}
+
+	cpufreq_dt = platform_device_register_simple("cpufreq-dt", -1, NULL, 0);
+	ret = PTR_ERR_OR_ZERO(cpufreq_dt);
+	if (ret) {
+		dev_err(cpu_dev, "Failed to create platform device, %d\n", ret);
+		goto remove_opp;
+	}
+
+	return 0;
+
+remove_opp:
+	dev_pm_opp_remove_all_dynamic(cpu_dev);
+
+	return ret;
+}
+
+static void raspberrypi_cpufreq_remove(struct platform_device *pdev)
+{
+	struct device *cpu_dev;
+
+	cpu_dev = get_cpu_device(0);
+	if (cpu_dev)
+		dev_pm_opp_remove_all_dynamic(cpu_dev);
+
+	platform_device_unregister(cpufreq_dt);
+}
+
+/*
+ * Since the driver depends on clk-raspberrypi, which may return EPROBE_DEFER,
+ * all the activity is performed in the probe, which may be defered as well.
+ */
+static struct platform_driver raspberrypi_cpufreq_driver = {
+	.driver = {
+		.name = "raspberrypi-cpufreq",
+	},
+	.probe          = raspberrypi_cpufreq_probe,
+	.remove		= raspberrypi_cpufreq_remove,
+};
+module_platform_driver(raspberrypi_cpufreq_driver);
+
+MODULE_AUTHOR("Nicolas Saenz Julienne <nsaenzjulienne@suse.de");
+MODULE_DESCRIPTION("Raspberry Pi cpufreq driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:raspberrypi-cpufreq");