1 files changed, 48 insertions, 0 deletions
diff --git a/samples/bpf/test_overhead_kprobe_kern.c b/samples/bpf/test_overhead_kprobe_kern.c
new file mode 100644
index 000000000..f6d593e47
--- /dev/null
+++ b/samples/bpf/test_overhead_kprobe_kern.c
@@ -0,0 +1,48 @@
+/* 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/version.h>
+#include <linux/ptrace.h>
+#include <uapi/linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+
+#define _(P)                                                                   \
+	({                                                                     \
+		typeof(P) val = 0;                                             \
+		bpf_probe_read_kernel(&val, sizeof(val), &(P));                \
+		val;                                                           \
+	})
+
+SEC("kprobe/__set_task_comm")
+int prog(struct pt_regs *ctx)
+{
+	struct signal_struct *signal;
+	struct task_struct *tsk;
+	char oldcomm[16] = {};
+	char newcomm[16] = {};
+	u16 oom_score_adj;
+	u32 pid;
+
+	tsk = (void *)PT_REGS_PARM1(ctx);
+
+	pid = _(tsk->pid);
+	bpf_probe_read_kernel(oldcomm, sizeof(oldcomm), &tsk->comm);
+	bpf_probe_read_kernel(newcomm, sizeof(newcomm),
+			      (void *)PT_REGS_PARM2(ctx));
+	signal = _(tsk->signal);
+	oom_score_adj = _(signal->oom_score_adj);
+	return 0;
+}
+
+SEC("kprobe/urandom_read")
+int prog2(struct pt_regs *ctx)
+{
+	return 0;
+}
+
+char _license[] SEC("license") = "GPL";
+u32 _version SEC("version") = LINUX_VERSION_CODE;