Messages in this thread |  | | Subject | Re: [PATCH v2 bpf-next 05/13] bpf: Rename BPF_XADD and prepare to encode other atomics in .imm | From | Yonghong Song <> | Date | Fri, 27 Nov 2020 19:43:46 -0800 |
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On 11/27/20 9:57 AM, Brendan Jackman wrote: > A subsequent patch will add additional atomic operations. These new > operations will use the same opcode field as the existing XADD, with > the immediate discriminating different operations. > > In preparation, rename the instruction mode BPF_ATOMIC and start > calling the zero immediate BPF_ADD. > > This is possible (doesn't break existing valid BPF progs) because the > immediate field is currently reserved MBZ and BPF_ADD is zero. > > All uses are removed from the tree but the BPF_XADD definition is > kept around to avoid breaking builds for people including kernel > headers. > > Signed-off-by: Brendan Jackman <jackmanb@google.com> > --- > Documentation/networking/filter.rst | 30 +++++++----- > arch/arm/net/bpf_jit_32.c | 7 ++- > arch/arm64/net/bpf_jit_comp.c | 16 +++++-- > arch/mips/net/ebpf_jit.c | 11 +++-- > arch/powerpc/net/bpf_jit_comp64.c | 25 ++++++++-- > arch/riscv/net/bpf_jit_comp32.c | 20 ++++++-- > arch/riscv/net/bpf_jit_comp64.c | 16 +++++-- > arch/s390/net/bpf_jit_comp.c | 27 ++++++----- > arch/sparc/net/bpf_jit_comp_64.c | 17 +++++-- > arch/x86/net/bpf_jit_comp.c | 46 ++++++++++++++----- > arch/x86/net/bpf_jit_comp32.c | 6 +-- > drivers/net/ethernet/netronome/nfp/bpf/jit.c | 14 ++++-- > drivers/net/ethernet/netronome/nfp/bpf/main.h | 4 +- > .../net/ethernet/netronome/nfp/bpf/verifier.c | 15 ++++-- > include/linux/filter.h | 8 ++-- > include/uapi/linux/bpf.h | 3 +- > kernel/bpf/core.c | 31 +++++++++---- > kernel/bpf/disasm.c | 6 ++- > kernel/bpf/verifier.c | 24 ++++++---- > lib/test_bpf.c | 2 +- > samples/bpf/bpf_insn.h | 4 +- > samples/bpf/sock_example.c | 2 +- > samples/bpf/test_cgrp2_attach.c | 4 +- > tools/include/linux/filter.h | 7 +-- > tools/include/uapi/linux/bpf.h | 3 +- > .../bpf/prog_tests/cgroup_attach_multi.c | 4 +- > tools/testing/selftests/bpf/verifier/ctx.c | 7 ++- > .../testing/selftests/bpf/verifier/leak_ptr.c | 4 +- > tools/testing/selftests/bpf/verifier/unpriv.c | 3 +- > tools/testing/selftests/bpf/verifier/xadd.c | 2 +- > 30 files changed, 248 insertions(+), 120 deletions(-) > > diff --git a/Documentation/networking/filter.rst b/Documentation/networking/filter.rst [...] > diff --git a/drivers/net/ethernet/netronome/nfp/bpf/jit.c b/drivers/net/ethernet/netronome/nfp/bpf/jit.c > index 0a721f6e8676..1c9efc74edfc 100644 > --- a/drivers/net/ethernet/netronome/nfp/bpf/jit.c > +++ b/drivers/net/ethernet/netronome/nfp/bpf/jit.c > @@ -3109,13 +3109,19 @@ mem_xadd(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta, bool is64) > return 0; > } > > -static int mem_xadd4(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta) > +static int mem_atomic4(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta) > { > + if (meta->insn.off != BPF_ADD) > + return -EOPNOTSUPP;
You probably missed this change. it should be meta->insn.imm != BPF_ADD.
> + > return mem_xadd(nfp_prog, meta, false); > } > > -static int mem_xadd8(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta) > +static int mem_atomic8(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta) > { > + if (meta->insn.off != BPF_ADD)
same as above.
> + return -EOPNOTSUPP; > + > return mem_xadd(nfp_prog, meta, true); > } > > @@ -3475,8 +3481,8 @@ static const instr_cb_t instr_cb[256] = { > [BPF_STX | BPF_MEM | BPF_H] = mem_stx2, > [BPF_STX | BPF_MEM | BPF_W] = mem_stx4, > [BPF_STX | BPF_MEM | BPF_DW] = mem_stx8, > - [BPF_STX | BPF_XADD | BPF_W] = mem_xadd4, > - [BPF_STX | BPF_XADD | BPF_DW] = mem_xadd8, > + [BPF_STX | BPF_ATOMIC | BPF_W] = mem_atomic4, > + [BPF_STX | BPF_ATOMIC | BPF_DW] = mem_atomic8, > [BPF_ST | BPF_MEM | BPF_B] = mem_st1, > [BPF_ST | BPF_MEM | BPF_H] = mem_st2, > [BPF_ST | BPF_MEM | BPF_W] = mem_st4, [...]
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