1 files changed, 109 insertions, 0 deletions
diff --git a/samples/bpf/test_cgrp2_array_pin.c b/samples/bpf/test_cgrp2_array_pin.c
new file mode 100644
index 000000000000..70e86f7be69d
--- /dev/null
+++ b/samples/bpf/test_cgrp2_array_pin.c
@@ -0,0 +1,109 @@
+/* Copyright (c) 2016 Facebook
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ */
+#include <linux/unistd.h>
+#include <linux/bpf.h>
+
+#include <stdio.h>
+#include <stdint.h>
+#include <unistd.h>
+#include <string.h>
+#include <errno.h>
+#include <fcntl.h>
+
+#include "libbpf.h"
+
+static void usage(void)
+{
+	printf("Usage: test_cgrp2_array_pin [...]\n");
+	printf("       -F <file>   File to pin an BPF cgroup array\n");
+	printf("       -U <file>   Update an already pinned BPF cgroup array\n");
+	printf("       -v <value>  Full path of the cgroup2\n");
+	printf("       -h          Display this help\n");
+}
+
+int main(int argc, char **argv)
+{
+	const char *pinned_file = NULL, *cg2 = NULL;
+	int create_array = 1;
+	int array_key = 0;
+	int array_fd = -1;
+	int cg2_fd = -1;
+	int ret = -1;
+	int opt;
+
+	while ((opt = getopt(argc, argv, "F:U:v:")) != -1) {
+		switch (opt) {
+		/* General args */
+		case 'F':
+			pinned_file = optarg;
+			break;
+		case 'U':
+			pinned_file = optarg;
+			create_array = 0;
+			break;
+		case 'v':
+			cg2 = optarg;
+			break;
+		default:
+			usage();
+			goto out;
+		}
+	}
+
+	if (!cg2 || !pinned_file) {
+		usage();
+		goto out;
+	}
+
+	cg2_fd = open(cg2, O_RDONLY);
+	if (cg2_fd < 0) {
+		fprintf(stderr, "open(%s,...): %s(%d)\n",
+			cg2, strerror(errno), errno);
+		goto out;
+	}
+
+	if (create_array) {
+		array_fd = bpf_create_map(BPF_MAP_TYPE_CGROUP_ARRAY,
+					  sizeof(uint32_t), sizeof(uint32_t),
+					  1, 0);
+		if (array_fd < 0) {
+			fprintf(stderr,
+				"bpf_create_map(BPF_MAP_TYPE_CGROUP_ARRAY,...): %s(%d)\n",
+				strerror(errno), errno);
+			goto out;
+		}
+	} else {
+		array_fd = bpf_obj_get(pinned_file);
+		if (array_fd < 0) {
+			fprintf(stderr, "bpf_obj_get(%s): %s(%d)\n",
+				pinned_file, strerror(errno), errno);
+			goto out;
+		}
+	}
+
+	ret = bpf_update_elem(array_fd, &array_key, &cg2_fd, 0);
+	if (ret) {
+		perror("bpf_update_elem");
+		goto out;
+	}
+
+	if (create_array) {
+		ret = bpf_obj_pin(array_fd, pinned_file);
+		if (ret) {
+			fprintf(stderr, "bpf_obj_pin(..., %s): %s(%d)\n",
+				pinned_file, strerror(errno), errno);
+			goto out;
+		}
+	}
+
+out:
+	if (array_fd != -1)
+		close(array_fd);
+	if (cg2_fd != -1)
+		close(cg2_fd);
+	return ret;
+}