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, 76 insertions, 0 deletions

diff --git a/include/net/selftests.h b/include/net/selftests.h
new file mode 100644
index 000000000..c36e07406
--- /dev/null
+++ b/include/net/selftests.h
@@ -0,0 +1,76 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _NET_SELFTESTS
+#define _NET_SELFTESTS
+
+#include <linux/ethtool.h>
+#include <linux/netdevice.h>
+
+struct net_packet_attrs {
+	const unsigned char *src;
+	const unsigned char *dst;
+	u32 ip_src;
+	u32 ip_dst;
+	bool tcp;
+	u16 sport;
+	u16 dport;
+	int timeout;
+	int size;
+	int max_size;
+	u8 id;
+	u16 queue_mapping;
+	bool bad_csum;
+};
+
+struct net_test_priv {
+	struct net_packet_attrs *packet;
+	struct packet_type pt;
+	struct completion comp;
+	int double_vlan;
+	int vlan_id;
+	int ok;
+};
+
+struct netsfhdr {
+	__be32 version;
+	__be64 magic;
+	u8 id;
+} __packed;
+
+#define NET_TEST_PKT_SIZE (sizeof(struct ethhdr) + sizeof(struct iphdr) + \
+			   sizeof(struct netsfhdr))
+#define NET_TEST_PKT_MAGIC	0xdeadcafecafedeadULL
+#define NET_LB_TIMEOUT		msecs_to_jiffies(200)
+
+#if IS_ENABLED(CONFIG_NET_SELFTESTS)
+
+struct sk_buff *net_test_get_skb(struct net_device *ndev, u8 id,
+				 struct net_packet_attrs *attr);
+void net_selftest(struct net_device *ndev, struct ethtool_test *etest,
+		  u64 *buf);
+int net_selftest_get_count(void);
+void net_selftest_get_strings(u8 *data);
+
+#else
+
+static inline struct sk_buff *net_test_get_skb(struct net_device *ndev, u8 id,
+					       struct net_packet_attrs *attr)
+{
+	return NULL;
+}
+
+static inline void net_selftest(struct net_device *ndev, struct ethtool_test *etest,
+				u64 *buf)
+{
+}
+
+static inline int net_selftest_get_count(void)
+{
+	return 0;
+}
+
+static inline void net_selftest_get_strings(u8 *data)
+{
+}
+
+#endif
+#endif /* _NET_SELFTESTS */