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-rw-r--r--samples/bpf/sampleip_kern.c38
1 files changed, 38 insertions, 0 deletions
diff --git a/samples/bpf/sampleip_kern.c b/samples/bpf/sampleip_kern.c
new file mode 100644
index 0000000000..a3f8a3998e
--- /dev/null
+++ b/samples/bpf/sampleip_kern.c
@@ -0,0 +1,38 @@
+/* Copyright 2016 Netflix, Inc.
+ *
+ * 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/ptrace.h>
+#include <uapi/linux/bpf.h>
+#include <uapi/linux/bpf_perf_event.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+
+#define MAX_IPS 8192
+
+struct {
+ __uint(type, BPF_MAP_TYPE_HASH);
+ __type(key, u64);
+ __type(value, u32);
+ __uint(max_entries, MAX_IPS);
+} ip_map SEC(".maps");
+
+SEC("perf_event")
+int do_sample(struct bpf_perf_event_data *ctx)
+{
+ u64 ip;
+ u32 *value, init_val = 1;
+
+ ip = PT_REGS_IP(&ctx->regs);
+ value = bpf_map_lookup_elem(&ip_map, &ip);
+ if (value)
+ *value += 1;
+ else
+ /* E2BIG not tested for this example only */
+ bpf_map_update_elem(&ip_map, &ip, &init_val, BPF_NOEXIST);
+
+ return 0;
+}
+char _license[] SEC("license") = "GPL";