1 /*
2 * Copyright (C) 2018 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include <linux/bpf.h>
18 #include <stdbool.h>
19 #include <stdint.h>
20 #include <bpf_helpers.h>
21
22 /* Assume max of 1024 CPUs */
23 DEFINE_BPF_MAP(cpu_pid_map, ARRAY, int, uint32_t, 1024)
24
25 struct switch_args {
26 unsigned long long ignore;
27 char prev_comm[16];
28 int prev_pid;
29 int prev_prio;
30 long long prev_state;
31 char next_comm[16];
32 int next_pid;
33 int next_prio;
34 };
35
36 SEC("tracepoint/sched/sched_switch")
tp_sched_switch(struct switch_args * args)37 int tp_sched_switch(struct switch_args* args) {
38 int key;
39 uint32_t val;
40
41 key = bpf_get_smp_processor_id();
42 val = args->next_pid;
43
44 bpf_cpu_pid_map_update_elem(&key, &val, BPF_ANY);
45 return 0;
46 }
47
48 LICENSE("GPL");
49