forked from Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
46 lines
1.1 KiB
46 lines
1.1 KiB
// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) |
|
// Copyright (c) 2021 Facebook |
|
#include <linux/bpf.h> |
|
#include <linux/perf_event.h> |
|
#include <bpf/bpf_helpers.h> |
|
#include <bpf/bpf_tracing.h> |
|
#include "bperf.h" |
|
|
|
struct { |
|
__uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY); |
|
__uint(key_size, sizeof(__u32)); |
|
__uint(value_size, sizeof(int)); |
|
__uint(map_flags, BPF_F_PRESERVE_ELEMS); |
|
} events SEC(".maps"); |
|
|
|
reading_map prev_readings SEC(".maps"); |
|
reading_map diff_readings SEC(".maps"); |
|
|
|
SEC("raw_tp/sched_switch") |
|
int BPF_PROG(on_switch) |
|
{ |
|
struct bpf_perf_event_value val, *prev_val, *diff_val; |
|
__u32 key = bpf_get_smp_processor_id(); |
|
__u32 zero = 0; |
|
long err; |
|
|
|
prev_val = bpf_map_lookup_elem(&prev_readings, &zero); |
|
if (!prev_val) |
|
return 0; |
|
|
|
diff_val = bpf_map_lookup_elem(&diff_readings, &zero); |
|
if (!diff_val) |
|
return 0; |
|
|
|
err = bpf_perf_event_read_value(&events, key, &val, sizeof(val)); |
|
if (err) |
|
return 0; |
|
|
|
diff_val->counter = val.counter - prev_val->counter; |
|
diff_val->enabled = val.enabled - prev_val->enabled; |
|
diff_val->running = val.running - prev_val->running; |
|
*prev_val = val; |
|
return 0; |
|
} |
|
|
|
char LICENSE[] SEC("license") = "Dual BSD/GPL";
|
|
|