tools/testing/selftests/bpf/progs/iters_task.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* Copyright (C) 2023 Chuyi Zhou <[email protected]> */
   3
   4 #include "vmlinux.h"
   5 #include <bpf/bpf_helpers.h>
   6 #include <bpf/bpf_tracing.h>
   7 #include "bpf_misc.h"
   8 #include "bpf_experimental.h"
   9
  10 char _license[] SEC("license") = "GPL";
  11
  12 pid_t target_pid;
  13 int procs_cnt, threads_cnt, proc_threads_cnt, invalid_cnt;
  14
  15 void bpf_rcu_read_lock(void) __ksym;
  16 void bpf_rcu_read_unlock(void) __ksym;
  17
  18 SEC("fentry.s/" SYS_PREFIX "sys_getpgid")
  19 int iter_task_for_each_sleep(void *ctx)
  20 {
  21         struct task_struct *cur_task = bpf_get_current_task_btf();
  22         struct task_struct *pos;
  23
  24         if (cur_task->pid != target_pid)
  25                 return 0;
  26         procs_cnt = threads_cnt = proc_threads_cnt = 0;
  27
  28         bpf_rcu_read_lock();
  29         bpf_for_each(task, pos, NULL, ~0U) {
  30                 /* Below instructions shouldn't be executed for invalid flags */
  31                 invalid_cnt++;
  32         }
  33
  34         bpf_for_each(task, pos, NULL, BPF_TASK_ITER_PROC_THREADS) {
  35                 /* Below instructions shouldn't be executed for invalid task__nullable */
  36                 invalid_cnt++;
  37         }
  38
  39         bpf_for_each(task, pos, NULL, BPF_TASK_ITER_ALL_PROCS)
  40                 if (pos->pid == target_pid)
  41                         procs_cnt++;
  42
  43         bpf_for_each(task, pos, cur_task, BPF_TASK_ITER_PROC_THREADS)
  44                 proc_threads_cnt++;
  45
  46         bpf_for_each(task, pos, NULL, BPF_TASK_ITER_ALL_THREADS)
  47                 if (pos->tgid == target_pid)
  48                         threads_cnt++;
  49         bpf_rcu_read_unlock();
  50         return 0;
  51 }