selftests/bpf: Add a test for objects stuck in free_by_rcu_ttracegrafted

Delete all elements of BPF_F_NO_PREALLOC hash map in one batch. The first
free_bulk() starts RCU tasks trace GP and the rest of the elements are
freed while it's in flight. Wait for call_rcu_ttrace_in_progress to clear
in bpf_mem_cache of every cpu and check that free_by_rcu_ttrace and
waiting_for_gp_ttrace lists are empty.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20260930095920.601738-4-alexei.starovoitov@gmail.com
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>

1 files changed, 74 insertions, 0 deletions

diff --git a/include/net/ioam6.h b/include/net/ioam6.h
new file mode 100644
index 000000000..a75912fe2
--- /dev/null
+++ b/include/net/ioam6.h
@@ -0,0 +1,74 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ *  IPv6 IOAM implementation
+ *
+ *  Author:
+ *  Justin Iurman <justin.iurman@uliege.be>
+ */
+
+#ifndef _NET_IOAM6_H
+#define _NET_IOAM6_H
+
+#include <linux/net.h>
+#include <linux/ipv6.h>
+#include <linux/ioam6.h>
+#include <linux/ioam6_genl.h>
+#include <linux/rhashtable-types.h>
+
+struct ioam6_namespace {
+	struct rhash_head head;
+	struct rcu_head rcu;
+
+	struct ioam6_schema __rcu *schema;
+
+	__be16 id;
+	__be32 data;
+	__be64 data_wide;
+};
+
+struct ioam6_schema {
+	struct rhash_head head;
+	struct rcu_head rcu;
+
+	struct ioam6_namespace __rcu *ns;
+
+	u32 id;
+	int len;
+	__be32 hdr;
+
+	u8 data[];
+};
+
+struct ioam6_pernet_data {
+	struct mutex lock;
+	struct rhashtable namespaces;
+	struct rhashtable schemas;
+};
+
+static inline struct ioam6_pernet_data *ioam6_pernet(struct net *net)
+{
+#if IS_ENABLED(CONFIG_IPV6)
+	return net->ipv6.ioam6_data;
+#else
+	return NULL;
+#endif
+}
+
+struct ioam6_namespace *ioam6_namespace(struct net *net, __be16 id);
+void ioam6_fill_trace_data(struct sk_buff *skb,
+			   struct ioam6_namespace *ns,
+			   struct ioam6_trace_hdr *trace,
+			   bool is_input);
+
+u8 ioam6_trace_compute_nodelen(u32 trace_type);
+
+int ioam6_init(void);
+void ioam6_exit(void);
+
+int ioam6_iptunnel_init(void);
+void ioam6_iptunnel_exit(void);
+
+void ioam6_event(enum ioam6_event_type type, struct net *net, gfp_t gfp,
+		 void *opt, unsigned int opt_len);
+
+#endif /* _NET_IOAM6_H */