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, 161 insertions, 0 deletions

diff --git a/net/devlink/sh_dev.c b/net/devlink/sh_dev.c
new file mode 100644
index 000000000..85acce97e
--- /dev/null
+++ b/net/devlink/sh_dev.c
@@ -0,0 +1,161 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* Copyright (c) 2026, NVIDIA CORPORATION & AFFILIATES. All rights reserved. */
+
+#include <net/devlink.h>
+
+#include "devl_internal.h"
+
+static LIST_HEAD(shd_list);
+static DEFINE_MUTEX(shd_mutex); /* Protects shd_list and shd->list */
+
+/* This structure represents a shared devlink instance,
+ * there is one created per identifier (e.g., serial number).
+ */
+struct devlink_shd {
+	struct list_head list; /* Node in shd list */
+	const char *id; /* Identifier string (e.g., serial number) */
+	refcount_t refcount; /* Reference count */
+	size_t priv_size; /* Size of driver private data */
+	char priv[] __aligned(NETDEV_ALIGN) __counted_by(priv_size);
+};
+
+static struct devlink_shd *devlink_shd_lookup(const char *id)
+{
+	struct devlink_shd *shd;
+
+	list_for_each_entry(shd, &shd_list, list) {
+		if (!strcmp(shd->id, id))
+			return shd;
+	}
+
+	return NULL;
+}
+
+static struct devlink_shd *devlink_shd_create(const char *id,
+					      const struct devlink_ops *ops,
+					      size_t priv_size,
+					      const struct device_driver *driver)
+{
+	struct devlink_shd *shd;
+	struct devlink *devlink;
+
+	devlink = __devlink_alloc(ops, sizeof(struct devlink_shd) + priv_size,
+				  &init_net, NULL, driver);
+	if (!devlink)
+		return NULL;
+	shd = devlink_priv(devlink);
+
+	shd->id = kstrdup(id, GFP_KERNEL);
+	if (!shd->id)
+		goto err_devlink_free;
+	shd->priv_size = priv_size;
+	refcount_set(&shd->refcount, 1);
+
+	devl_lock(devlink);
+	devl_register(devlink);
+	devl_unlock(devlink);
+
+	list_add_tail(&shd->list, &shd_list);
+
+	return shd;
+
+err_devlink_free:
+	devlink_free(devlink);
+	return NULL;
+}
+
+static void devlink_shd_destroy(struct devlink_shd *shd)
+{
+	struct devlink *devlink = priv_to_devlink(shd);
+
+	list_del(&shd->list);
+	devl_lock(devlink);
+	devl_unregister(devlink);
+	devl_unlock(devlink);
+	kfree(shd->id);
+	devlink_free(devlink);
+}
+
+/**
+ * devlink_shd_get - Get or create a shared devlink instance
+ * @id: Identifier string (e.g., serial number) for the shared instance
+ * @ops: Devlink operations structure
+ * @priv_size: Size of private data structure
+ * @driver: Driver associated with the shared devlink instance
+ *
+ * Get an existing shared devlink instance identified by @id, or create
+ * a new one if it doesn't exist. Return the devlink instance with a
+ * reference held. The caller must call devlink_shd_put() when done.
+ *
+ * All callers sharing the same @id must pass identical @ops, @priv_size
+ * and @driver. A mismatch triggers a warning and returns NULL.
+ *
+ * Return: Pointer to the shared devlink instance on success,
+ *         NULL on failure
+ */
+struct devlink *devlink_shd_get(const char *id,
+				const struct devlink_ops *ops,
+				size_t priv_size,
+				const struct device_driver *driver)
+{
+	struct devlink *devlink;
+	struct devlink_shd *shd;
+
+	mutex_lock(&shd_mutex);
+
+	shd = devlink_shd_lookup(id);
+	if (!shd) {
+		shd = devlink_shd_create(id, ops, priv_size, driver);
+		goto unlock;
+	}
+
+	devlink = priv_to_devlink(shd);
+	if (WARN_ON_ONCE(devlink->ops != ops ||
+			 shd->priv_size != priv_size ||
+			 devlink->dev_driver != driver)) {
+		shd = NULL;
+		goto unlock;
+	}
+	refcount_inc(&shd->refcount);
+
+unlock:
+	mutex_unlock(&shd_mutex);
+	return shd ? priv_to_devlink(shd) : NULL;
+}
+EXPORT_SYMBOL_GPL(devlink_shd_get);
+
+/**
+ * devlink_shd_put - Release a reference on a shared devlink instance
+ * @devlink: Shared devlink instance
+ *
+ * Release a reference on a shared devlink instance obtained via
+ * devlink_shd_get().
+ */
+void devlink_shd_put(struct devlink *devlink)
+{
+	struct devlink_shd *shd;
+
+	mutex_lock(&shd_mutex);
+	shd = devlink_priv(devlink);
+	if (refcount_dec_and_test(&shd->refcount))
+		devlink_shd_destroy(shd);
+	mutex_unlock(&shd_mutex);
+}
+EXPORT_SYMBOL_GPL(devlink_shd_put);
+
+/**
+ * devlink_shd_get_priv - Get private data from shared devlink instance
+ * @devlink: Devlink instance
+ *
+ * Returns a pointer to the driver's private data structure within
+ * the shared devlink instance.
+ *
+ * Return: Pointer to private data
+ */
+void *devlink_shd_get_priv(struct devlink *devlink)
+{
+	struct devlink_shd *shd = devlink_priv(devlink);
+
+	return shd->priv;
+}
+EXPORT_SYMBOL_GPL(devlink_shd_get_priv);