diff options
Diffstat (limited to 'samples/bpf/tracex6_kern.c')
| -rw-r--r-- | samples/bpf/tracex6_kern.c | 28 |
1 files changed, 21 insertions, 7 deletions
diff --git a/samples/bpf/tracex6_kern.c b/samples/bpf/tracex6_kern.c index be479c4af9e2..e7d180305974 100644 --- a/samples/bpf/tracex6_kern.c +++ b/samples/bpf/tracex6_kern.c @@ -3,22 +3,36 @@ #include <uapi/linux/bpf.h> #include "bpf_helpers.h" -struct bpf_map_def SEC("maps") my_map = { +struct bpf_map_def SEC("maps") counters = { .type = BPF_MAP_TYPE_PERF_EVENT_ARRAY, .key_size = sizeof(int), .value_size = sizeof(u32), - .max_entries = 32, + .max_entries = 64, +}; +struct bpf_map_def SEC("maps") values = { + .type = BPF_MAP_TYPE_HASH, + .key_size = sizeof(int), + .value_size = sizeof(u64), + .max_entries = 64, }; -SEC("kprobe/sys_write") +SEC("kprobe/htab_map_get_next_key") int bpf_prog1(struct pt_regs *ctx) { - u64 count; u32 key = bpf_get_smp_processor_id(); - char fmt[] = "CPU-%d %llu\n"; + u64 count, *val; + s64 error; + + count = bpf_perf_event_read(&counters, key); + error = (s64)count; + if (error <= -2 && error >= -22) + return 0; - count = bpf_perf_event_read(&my_map, key); - bpf_trace_printk(fmt, sizeof(fmt), key, count); + val = bpf_map_lookup_elem(&values, &key); + if (val) + *val = count; + else + bpf_map_update_elem(&values, &key, &count, BPF_NOEXIST); return 0; } |