1 files changed, 63 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/testing_helpers.c b/tools/testing/selftests/bpf/testing_helpers.c
index dc9595ade8de6..648c7d3eb319c 100644
--- a/tools/testing/selftests/bpf/testing_helpers.c
+++ b/tools/testing/selftests/bpf/testing_helpers.c
@@ -9,6 +9,7 @@
 #include <bpf/libbpf.h>
 #include "test_progs.h"
 #include "testing_helpers.h"
+#include <linux/membarrier.h>
 
 int parse_num_list(const char *s, bool **num_set, int *num_set_len)
 {
@@ -326,3 +327,65 @@ __u64 read_perf_max_sample_freq(void)
 	fclose(f);
 	return sample_freq;
 }
+
+static int finit_module(int fd, const char *param_values, int flags)
+{
+	return syscall(__NR_finit_module, fd, param_values, flags);
+}
+
+static int delete_module(const char *name, int flags)
+{
+	return syscall(__NR_delete_module, name, flags);
+}
+
+void unload_bpf_testmod(bool verbose)
+{
+	if (kern_sync_rcu())
+		fprintf(stderr, "Failed to trigger kernel-side RCU sync!\n");
+	if (delete_module("bpf_testmod", 0)) {
+		if (errno == ENOENT) {
+			if (verbose)
+				fprintf(stdout, "bpf_testmod.ko is already unloaded.\n");
+			return;
+		}
+		fprintf(stderr, "Failed to unload bpf_testmod.ko from kernel: %d\n", -errno);
+		return;
+	}
+	if (verbose)
+		fprintf(stdout, "Successfully unloaded bpf_testmod.ko.\n");
+}
+
+int load_bpf_testmod(bool verbose)
+{
+	int fd;
+
+	/* ensure previous instance of the module is unloaded */
+	unload_bpf_testmod(verbose);
+
+	if (verbose)
+		fprintf(stdout, "Loading bpf_testmod.ko...\n");
+
+	fd = open("bpf_testmod.ko", O_RDONLY);
+	if (fd < 0) {
+		fprintf(stderr, "Can't find bpf_testmod.ko kernel module: %d\n", -errno);
+		return -ENOENT;
+	}
+	if (finit_module(fd, "", 0)) {
+		fprintf(stderr, "Failed to load bpf_testmod.ko into the kernel: %d\n", -errno);
+		close(fd);
+		return -EINVAL;
+	}
+	close(fd);
+
+	if (verbose)
+		fprintf(stdout, "Successfully loaded bpf_testmod.ko.\n");
+	return 0;
+}
+
+/*
+ * Trigger synchronize_rcu() in kernel.
+ */
+int kern_sync_rcu(void)
+{
+	return syscall(__NR_membarrier, MEMBARRIER_CMD_SHARED, 0, 0);
+}