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, 109 insertions, 0 deletions

diff --git a/drivers/pps/kc.c b/drivers/pps/kc.c
new file mode 100644
index 000000000..fbd23295a
--- /dev/null
+++ b/drivers/pps/kc.c
@@ -0,0 +1,109 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * PPS kernel consumer API
+ *
+ * Copyright (C) 2009-2010   Alexander Gordeev <lasaine@lvk.cs.msu.su>
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/pps_kernel.h>
+
+#include "kc.h"
+
+/*
+ * Global variables
+ */
+
+/* state variables to bind kernel consumer */
+static DEFINE_SPINLOCK(pps_kc_hardpps_lock);
+/* PPS API (RFC 2783): current source and mode for kernel consumer */
+static struct pps_device *pps_kc_hardpps_dev;	/* unique pointer to device */
+static int pps_kc_hardpps_mode;		/* mode bits for kernel consumer */
+
+/* pps_kc_bind - control PPS kernel consumer binding
+ * @pps: the PPS source
+ * @bind_args: kernel consumer bind parameters
+ *
+ * This function is used to bind or unbind PPS kernel consumer according to
+ * supplied parameters. Should not be called in interrupt context.
+ */
+int pps_kc_bind(struct pps_device *pps, struct pps_bind_args *bind_args)
+{
+	/* Check if another consumer is already bound */
+	spin_lock_irq(&pps_kc_hardpps_lock);
+
+	if (bind_args->edge == 0)
+		if (pps_kc_hardpps_dev == pps) {
+			pps_kc_hardpps_mode = 0;
+			pps_kc_hardpps_dev = NULL;
+			spin_unlock_irq(&pps_kc_hardpps_lock);
+			dev_info(&pps->dev, "unbound kernel"
+					" consumer\n");
+		} else {
+			spin_unlock_irq(&pps_kc_hardpps_lock);
+			dev_err(&pps->dev, "selected kernel consumer"
+					" is not bound\n");
+			return -EINVAL;
+		}
+	else
+		if (pps_kc_hardpps_dev == NULL ||
+				pps_kc_hardpps_dev == pps) {
+			pps_kc_hardpps_mode = bind_args->edge;
+			pps_kc_hardpps_dev = pps;
+			spin_unlock_irq(&pps_kc_hardpps_lock);
+			dev_info(&pps->dev, "bound kernel consumer: "
+				"edge=0x%x\n", bind_args->edge);
+		} else {
+			spin_unlock_irq(&pps_kc_hardpps_lock);
+			dev_err(&pps->dev, "another kernel consumer"
+					" is already bound\n");
+			return -EINVAL;
+		}
+
+	return 0;
+}
+
+/* pps_kc_remove - unbind kernel consumer on PPS source removal
+ * @pps: the PPS source
+ *
+ * This function is used to disable kernel consumer on PPS source removal
+ * if this source was bound to PPS kernel consumer. Can be called on any
+ * source safely. Should not be called in interrupt context.
+ */
+void pps_kc_remove(struct pps_device *pps)
+{
+	spin_lock_irq(&pps_kc_hardpps_lock);
+	if (pps == pps_kc_hardpps_dev) {
+		pps_kc_hardpps_mode = 0;
+		pps_kc_hardpps_dev = NULL;
+		spin_unlock_irq(&pps_kc_hardpps_lock);
+		dev_info(&pps->dev, "unbound kernel consumer"
+				" on device removal\n");
+	} else
+		spin_unlock_irq(&pps_kc_hardpps_lock);
+}
+
+/* pps_kc_event - call hardpps() on PPS event
+ * @pps: the PPS source
+ * @ts: PPS event timestamp
+ * @event: PPS event edge
+ *
+ * This function calls hardpps() when an event from bound PPS source occurs.
+ */
+void pps_kc_event(struct pps_device *pps, struct pps_event_time *ts,
+		int event)
+{
+	unsigned long flags;
+
+	/* Pass some events to kernel consumer if activated */
+	spin_lock_irqsave(&pps_kc_hardpps_lock, flags);
+	if (pps == pps_kc_hardpps_dev && event & pps_kc_hardpps_mode)
+		hardpps(&ts->ts_real, &ts->ts_raw);
+	spin_unlock_irqrestore(&pps_kc_hardpps_lock, flags);
+}