diff options
Diffstat (limited to 'tools/testing/selftests/bpf/progs/test_perf_buffer.c')
-rw-r--r-- | tools/testing/selftests/bpf/progs/test_perf_buffer.c | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/test_perf_buffer.c b/tools/testing/selftests/bpf/progs/test_perf_buffer.c new file mode 100644 index 0000000000..17d5b67744 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_perf_buffer.c @@ -0,0 +1,41 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2019 Facebook + +#include <linux/ptrace.h> +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> +#include <bpf/bpf_tracing.h> + +struct { + __uint(type, BPF_MAP_TYPE_ARRAY); + __type(key, int); + __type(value, int); + __uint(max_entries, 1); +} my_pid_map SEC(".maps"); + +struct { + __uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY); + __type(key, int); + __type(value, int); +} perf_buf_map SEC(".maps"); + +SEC("tp/raw_syscalls/sys_enter") +int handle_sys_enter(void *ctx) +{ + int zero = 0, *my_pid, cur_pid; + int cpu = bpf_get_smp_processor_id(); + + my_pid = bpf_map_lookup_elem(&my_pid_map, &zero); + if (!my_pid) + return 1; + + cur_pid = bpf_get_current_pid_tgid() >> 32; + if (cur_pid != *my_pid) + return 1; + + bpf_perf_event_output(ctx, &perf_buf_map, BPF_F_CURRENT_CPU, + &cpu, sizeof(cpu)); + return 1; +} + +char _license[] SEC("license") = "GPL"; |