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, 164 insertions, 0 deletions

diff --git a/net/802/psnap.c b/net/802/psnap.c
new file mode 100644
index 000000000..8ae835e1c
--- /dev/null
+++ b/net/802/psnap.c
@@ -0,0 +1,164 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *	SNAP data link layer. Derived from 802.2
+ *
+ *		Alan Cox <alan@lxorguk.ukuu.org.uk>,
+ *		from the 802.2 layer by Greg Page.
+ *		Merged in additions from Greg Page's psnap.c.
+ */
+
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <linux/slab.h>
+#include <net/datalink.h>
+#include <net/llc.h>
+#include <net/psnap.h>
+#include <linux/mm.h>
+#include <linux/in.h>
+#include <linux/init.h>
+#include <linux/rculist.h>
+
+static LIST_HEAD(snap_list);
+static DEFINE_SPINLOCK(snap_lock);
+static struct llc_sap *snap_sap;
+
+/*
+ *	Find a snap client by matching the 5 bytes.
+ */
+static struct datalink_proto *find_snap_client(const unsigned char *desc)
+{
+	struct datalink_proto *proto = NULL, *p;
+
+	list_for_each_entry_rcu(p, &snap_list, node, lockdep_is_held(&snap_lock)) {
+		if (!memcmp(p->type, desc, 5)) {
+			proto = p;
+			break;
+		}
+	}
+	return proto;
+}
+
+/*
+ *	A SNAP packet has arrived
+ */
+static int snap_rcv(struct sk_buff *skb, struct net_device *dev,
+		    struct packet_type *pt, struct net_device *orig_dev)
+{
+	int rc = 1;
+	struct datalink_proto *proto;
+	static struct packet_type snap_packet_type = {
+		.type = cpu_to_be16(ETH_P_SNAP),
+	};
+
+	if (unlikely(!pskb_may_pull(skb, 5)))
+		goto drop;
+
+	rcu_read_lock();
+	proto = find_snap_client(skb->data);
+	if (proto) {
+		/* Pass the frame on. */
+		skb_pull_rcsum(skb, 5);
+		skb_reset_transport_header(skb);
+		rc = proto->rcvfunc(skb, dev, &snap_packet_type, orig_dev);
+	}
+	rcu_read_unlock();
+
+	if (unlikely(!proto))
+		goto drop;
+
+out:
+	return rc;
+
+drop:
+	kfree_skb(skb);
+	goto out;
+}
+
+/*
+ *	Put a SNAP header on a frame and pass to 802.2
+ */
+static int snap_request(struct datalink_proto *dl,
+			struct sk_buff *skb, const u8 *dest)
+{
+	memcpy(skb_push(skb, 5), dl->type, 5);
+	llc_build_and_send_ui_pkt(snap_sap, skb, dest, snap_sap->laddr.lsap);
+	return 0;
+}
+
+/*
+ *	Set up the SNAP layer
+ */
+EXPORT_SYMBOL(register_snap_client);
+EXPORT_SYMBOL(unregister_snap_client);
+
+static const char snap_err_msg[] __initconst =
+	KERN_CRIT "SNAP - unable to register with 802.2\n";
+
+static int __init snap_init(void)
+{
+	snap_sap = llc_sap_open(0xAA, snap_rcv);
+	if (!snap_sap) {
+		printk(snap_err_msg);
+		return -EBUSY;
+	}
+
+	return 0;
+}
+
+module_init(snap_init);
+
+static void __exit snap_exit(void)
+{
+	llc_sap_put(snap_sap);
+}
+
+module_exit(snap_exit);
+
+
+/*
+ *	Register SNAP clients. We don't yet use this for IP.
+ */
+struct datalink_proto *register_snap_client(const unsigned char *desc,
+					    int (*rcvfunc)(struct sk_buff *,
+							   struct net_device *,
+							   struct packet_type *,
+							   struct net_device *))
+{
+	struct datalink_proto *proto = NULL;
+
+	spin_lock_bh(&snap_lock);
+
+	if (find_snap_client(desc))
+		goto out;
+
+	proto = kmalloc_obj(*proto, GFP_ATOMIC);
+	if (proto) {
+		memcpy(proto->type, desc, 5);
+		proto->rcvfunc		= rcvfunc;
+		proto->header_length	= 5 + 3; /* snap + 802.2 */
+		proto->request		= snap_request;
+		list_add_rcu(&proto->node, &snap_list);
+	}
+out:
+	spin_unlock_bh(&snap_lock);
+
+	return proto;
+}
+
+/*
+ *	Unregister SNAP clients. Protocols no longer want to play with us ...
+ */
+void unregister_snap_client(struct datalink_proto *proto)
+{
+	spin_lock_bh(&snap_lock);
+	list_del_rcu(&proto->node);
+	spin_unlock_bh(&snap_lock);
+
+	synchronize_net();
+
+	kfree(proto);
+}
+
+MODULE_DESCRIPTION("SNAP data link layer. Derived from 802.2");
+MODULE_LICENSE("GPL");