diff options
| author | Brendan Jackman <jackmanb@google.com> | 2021-01-14 18:17:50 +0000 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2021-01-14 18:34:29 -0800 |
| commit | 98d666d05a1d9706bb3fe972157fa6155dbb180f (patch) | |
| tree | 7d756eb0f033b90497e951419d8c682c603a472f /tools/testing/selftests/bpf/verifier/atomic_xchg.c | |
| parent | 981f94c3e92146705baf97fb417a5ed1ab1a79a5 (diff) | |
bpf: Add tests for new BPF atomic operations
The prog_test that's added depends on Clang/LLVM features added by
Yonghong in commit 286daafd6512 (was https://reviews.llvm.org/D72184).
Note the use of a define called ENABLE_ATOMICS_TESTS: this is used
to:
- Avoid breaking the build for people on old versions of Clang
- Avoid needing separate lists of test objects for no_alu32, where
atomics are not supported even if Clang has the feature.
The atomics_test.o BPF object is built unconditionally both for
test_progs and test_progs-no_alu32. For test_progs, if Clang supports
atomics, ENABLE_ATOMICS_TESTS is defined, so it includes the proper
test code. Otherwise, progs and global vars are defined anyway, as
stubs; this means that the skeleton user code still builds.
The atomics_test.o userspace object is built once and used for both
test_progs and test_progs-no_alu32. A variable called skip_tests is
defined in the BPF object's data section, which tells the userspace
object whether to skip the atomics test.
Signed-off-by: Brendan Jackman <jackmanb@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210114181751.768687-11-jackmanb@google.com
Diffstat (limited to 'tools/testing/selftests/bpf/verifier/atomic_xchg.c')
| -rw-r--r-- | tools/testing/selftests/bpf/verifier/atomic_xchg.c | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/verifier/atomic_xchg.c b/tools/testing/selftests/bpf/verifier/atomic_xchg.c new file mode 100644 index 000000000000..33e2d6c973ee --- /dev/null +++ b/tools/testing/selftests/bpf/verifier/atomic_xchg.c @@ -0,0 +1,46 @@ +{ + "atomic exchange smoketest - 64bit", + .insns = { + /* val = 3; */ + BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 3), + /* old = atomic_xchg(&val, 4); */ + BPF_MOV64_IMM(BPF_REG_1, 4), + BPF_ATOMIC_OP(BPF_DW, BPF_XCHG, BPF_REG_10, BPF_REG_1, -8), + /* if (old != 3) exit(1); */ + BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 3, 2), + BPF_MOV64_IMM(BPF_REG_0, 1), + BPF_EXIT_INSN(), + /* if (val != 4) exit(2); */ + BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_10, -8), + BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 4, 2), + BPF_MOV64_IMM(BPF_REG_0, 2), + BPF_EXIT_INSN(), + /* exit(0); */ + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }, + .result = ACCEPT, +}, +{ + "atomic exchange smoketest - 32bit", + .insns = { + /* val = 3; */ + BPF_ST_MEM(BPF_W, BPF_REG_10, -4, 3), + /* old = atomic_xchg(&val, 4); */ + BPF_MOV32_IMM(BPF_REG_1, 4), + BPF_ATOMIC_OP(BPF_W, BPF_XCHG, BPF_REG_10, BPF_REG_1, -4), + /* if (old != 3) exit(1); */ + BPF_JMP32_IMM(BPF_JEQ, BPF_REG_1, 3, 2), + BPF_MOV32_IMM(BPF_REG_0, 1), + BPF_EXIT_INSN(), + /* if (val != 4) exit(2); */ + BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_10, -4), + BPF_JMP32_IMM(BPF_JEQ, BPF_REG_0, 4, 2), + BPF_MOV32_IMM(BPF_REG_0, 2), + BPF_EXIT_INSN(), + /* exit(0); */ + BPF_MOV32_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }, + .result = ACCEPT, +}, |