tools/testing/selftests/bpf/prog_tests/kptr_xchg_inline.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* Copyright (C) 2023. Huawei Technologies Co., Ltd */
   3 #include <test_progs.h>
   4
   5 #include "linux/filter.h"
   6 #include "kptr_xchg_inline.skel.h"
   7
   8 void test_kptr_xchg_inline(void)
   9 {
  10         struct kptr_xchg_inline *skel;
  11         struct bpf_insn *insn = NULL;
  12         struct bpf_insn exp;
  13         unsigned int cnt;
  14         int err;
  15
  16 #if !(defined(__x86_64__) || defined(__aarch64__) || \
  17       (defined(__riscv) && __riscv_xlen == 64))
  18         test__skip();
  19         return;
  20 #endif
  21
  22         skel = kptr_xchg_inline__open_and_load();
  23         if (!ASSERT_OK_PTR(skel, "open_load"))
  24                 return;
  25
  26         err = get_xlated_program(bpf_program__fd(skel->progs.kptr_xchg_inline), &insn, &cnt);
  27         if (!ASSERT_OK(err, "prog insn"))
  28                 goto out;
  29
  30         /* The original instructions are:
  31          * r1 = map[id:xxx][0]+0
  32          * r2 = 0
  33          * call bpf_kptr_xchg#yyy
  34          *
  35          * call bpf_kptr_xchg#yyy will be inlined as:
  36          * r0 = r2
  37          * r0 = atomic64_xchg((u64 *)(r1 +0), r0)
  38          */
  39         if (!ASSERT_GT(cnt, 5, "insn cnt"))
  40                 goto out;
  41
  42         exp = BPF_MOV64_REG(BPF_REG_0, BPF_REG_2);
  43         if (!ASSERT_OK(memcmp(&insn[3], &exp, sizeof(exp)), "mov"))
  44                 goto out;
  45
  46         exp = BPF_ATOMIC_OP(BPF_DW, BPF_XCHG, BPF_REG_1, BPF_REG_0, 0);
  47         if (!ASSERT_OK(memcmp(&insn[4], &exp, sizeof(exp)), "xchg"))
  48                 goto out;
  49 out:
  50         free(insn);
  51         kptr_xchg_inline__destroy(skel);
  52 }