summaryrefslogtreecommitdiffstats
path: root/tools/perf/examples/bpf/hello.c
diff options
context:
space:
mode:
Diffstat (limited to 'tools/perf/examples/bpf/hello.c')
-rw-r--r--tools/perf/examples/bpf/hello.c24
1 files changed, 21 insertions, 3 deletions
diff --git a/tools/perf/examples/bpf/hello.c b/tools/perf/examples/bpf/hello.c
index cf3c2fdc7f79..e9080b0df158 100644
--- a/tools/perf/examples/bpf/hello.c
+++ b/tools/perf/examples/bpf/hello.c
@@ -1,9 +1,27 @@
-#include <stdio.h>
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
-int syscall_enter(openat)(void *args)
+struct __bpf_stdout__ {
+ __uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY);
+ __type(key, int);
+ __type(value, __u32);
+ __uint(max_entries, __NR_CPUS__);
+} __bpf_stdout__ SEC(".maps");
+
+#define puts(from) \
+ ({ const int __len = sizeof(from); \
+ char __from[sizeof(from)] = from; \
+ bpf_perf_event_output(args, &__bpf_stdout__, BPF_F_CURRENT_CPU, \
+ &__from, __len & (sizeof(from) - 1)); })
+
+struct syscall_enter_args;
+
+SEC("raw_syscalls:sys_enter")
+int sys_enter(struct syscall_enter_args *args)
{
puts("Hello, world\n");
return 0;
}
-license(GPL);
+char _license[] SEC("license") = "GPL";