Re: [PATCH bpf-next v3 0/4] bpf, arm64: support more atomic ops

[Hou Tao <houtao1@huawei.com>]

ping ?

On 1/30/2022 6:04 AM, Hou Tao wrote:
> Hi,
>
> Atomics support in bpf has already been done by "Atomics for eBPF"
> patch series [1], but it only adds support for x86, and this patchset
> adds support for arm64.
>
> Patch #1 & patch #2 are arm64 related. Patch #1 moves the common used
> macro AARCH64_BREAK_FAULT into insn-def.h for insn.h. Patch #2 adds
> necessary encoder helpers for atomic operations.
>
> Patch #3 implements atomic[64]_fetch_add, atomic[64]_[fetch_]{and,or,xor}
> and atomic[64]_{xchg|cmpxchg} for arm64 bpf. Patch #4 changes the type of
> test program from fentry/ to raw_tp/ for atomics test.
>
> For cpus_have_cap(ARM64_HAS_LSE_ATOMICS) case and no-LSE-ATOMICS case,
> ./test_verifier, "./test_progs -t atomic", and "insmod ./test_bpf.ko"
> are exercised and passed correspondingly.
>
> Comments are always welcome.
>
> Regards,
> Tao
>
> [1]: https://lore.kernel.org/bpf/20210114181751.768687-2-jackmanb@google.com/
>
> Change Log:
> v3:
>  * split arm64 insn related code into a separated patch (from Mark)
>  * update enum name in aarch64_insn_mem_atomic_op (from Mark)
>  * consider all cases for aarch64_insn_mem_order_type and
>    aarch64_insn_mb_type (from Mark)
>  * exercise and pass "insmod ./test_bpf.ko" test (suggested by Daniel)
>  * remove aarch64_insn_gen_store_release_ex() and extend
>    aarch64_insn_ldst_type instead
>  * compile aarch64_insn_gen_atomic_ld_op(), aarch64_insn_gen_cas() and
>    emit_lse_atomic() out when CONFIG_ARM64_LSE_ATOMICS is disabled.
>
> v2: https://lore.kernel.org/bpf/20220127075322.675323-1-houtao1@huawei.com/
>   * patch #1: use two separated ASSERT_OK() instead of ASSERT_TRUE()
>   * add Acked-by tag for both patches
>
> v1: https://lore.kernel.org/bpf/20220121135632.136976-1-houtao1@huawei.com/
>
> Hou Tao (4):
>   arm64: move AARCH64_BREAK_FAULT into insn-def.h
>   arm64: insn: add encoders for atomic operations
>   bpf, arm64: support more atomic operations
>   selftests/bpf: use raw_tp program for atomic test
>
>  arch/arm64/include/asm/debug-monitors.h       |  12 -
>  arch/arm64/include/asm/insn-def.h             |  14 ++
>  arch/arm64/include/asm/insn.h                 |  80 ++++++-
>  arch/arm64/lib/insn.c                         | 185 +++++++++++++--
>  arch/arm64/net/bpf_jit.h                      |  44 +++-
>  arch/arm64/net/bpf_jit_comp.c                 | 223 ++++++++++++++----
>  .../selftests/bpf/prog_tests/atomics.c        |  91 ++-----
>  tools/testing/selftests/bpf/progs/atomics.c   |  28 +--
>  8 files changed, 517 insertions(+), 160 deletions(-)
>