diff options
Diffstat (limited to 'tools/testing/selftests/bpf/progs/test_mmap.c')
| -rw-r--r-- | tools/testing/selftests/bpf/progs/test_mmap.c | 45 |
1 files changed, 45 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/test_mmap.c b/tools/testing/selftests/bpf/progs/test_mmap.c new file mode 100644 index 000000000000..0d2ec9fbcf61 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_mmap.c @@ -0,0 +1,45 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2019 Facebook + +#include <linux/bpf.h> +#include <stdint.h> +#include "bpf_helpers.h" + +char _license[] SEC("license") = "GPL"; + +struct { + __uint(type, BPF_MAP_TYPE_ARRAY); + __uint(max_entries, 512 * 4); /* at least 4 pages of data */ + __uint(map_flags, BPF_F_MMAPABLE); + __type(key, __u32); + __type(value, __u64); +} data_map SEC(".maps"); + +static volatile __u64 in_val; +static volatile __u64 out_val; + +SEC("raw_tracepoint/sys_enter") +int test_mmap(void *ctx) +{ + int zero = 0, one = 1, two = 2, far = 1500; + __u64 val, *p; + + out_val = in_val; + + /* data_map[2] = in_val; */ + bpf_map_update_elem(&data_map, &two, (const void *)&in_val, 0); + + /* data_map[1] = data_map[0] * 2; */ + p = bpf_map_lookup_elem(&data_map, &zero); + if (p) { + val = (*p) * 2; + bpf_map_update_elem(&data_map, &one, &val, 0); + } + + /* data_map[far] = in_val * 3; */ + val = in_val * 3; + bpf_map_update_elem(&data_map, &far, &val, 0); + + return 0; +} + |