Message ID | cover.1616430991.git.christophe.leroy@csgroup.eu |
---|---|
Headers | show |
Series | Implement EBPF on powerpc32 | expand |
Le 22/03/2021 à 18:53, Andrii Nakryiko a écrit : > On Mon, Mar 22, 2021 at 9:37 AM Christophe Leroy > <christophe.leroy@csgroup.eu> wrote: >> >> This series implements extended BPF on powerpc32. For the implementation >> details, see the patch before the last. >> >> The following operations are not implemented: >> >> case BPF_ALU64 | BPF_DIV | BPF_X: /* dst /= src */ >> case BPF_ALU64 | BPF_MOD | BPF_X: /* dst %= src */ >> case BPF_STX | BPF_XADD | BPF_DW: /* *(u64 *)(dst + off) += src */ >> >> The following operations are only implemented for power of two constants: >> >> case BPF_ALU64 | BPF_MOD | BPF_K: /* dst %= imm */ >> case BPF_ALU64 | BPF_DIV | BPF_K: /* dst /= imm */ >> >> Below are the results on a powerpc 885: >> - with the patch, with and without bpf_jit_enable >> - without the patch, with bpf_jit_enable (ie with CBPF) >> >> With the patch, with bpf_jit_enable = 1 : >> >> [ 60.826529] test_bpf: Summary: 378 PASSED, 0 FAILED, [354/366 JIT'ed] >> [ 60.832505] test_bpf: test_skb_segment: Summary: 2 PASSED, 0 FAILED >> >> With the patch, with bpf_jit_enable = 0 : >> >> [ 75.186337] test_bpf: Summary: 378 PASSED, 0 FAILED, [0/366 JIT'ed] >> [ 75.192325] test_bpf: test_skb_segment: Summary: 2 PASSED, 0 FAILED >> >> Without the patch, with bpf_jit_enable = 1 : >> >> [ 186.112429] test_bpf: Summary: 371 PASSED, 7 FAILED, [119/366 JIT'ed] >> >> Couldn't run test_progs because it doesn't build (clang 11 crashes during the build). > > Can you please try checking out the latest clang from sources and use > that one instead? The crash is fixed, it builds one step more, then fails at: [root@PC-server-ldb bpf]# make CROSS_COMPILE=ppc-linux- ARCH=powerpc V=1 /root/gen_ldb/linux-powerpc/tools/testing/selftests/bpf/host-tools/sbin/bpftool gen skeleton /root/gen_ldb/linux-powerpc/tools/testing/selftests/bpf/atomic_bounds.o > /root/gen_ldb/linux-powerpc/tools/testing/selftests/bpf/atomic_bounds.skel.h libbpf: elf: endianness mismatch in atomic_bounds. Error: failed to open BPF object file: Endian mismatch I'm cross-building on x86 for powerpc/32 [root@PC-server-ldb bpf]# file atomic_bounds.o atomic_bounds.o: ELF 64-bit MSB relocatable, eBPF, version 1 (SYSV), with debug_info, not stripped Christophe
On Fri, Mar 26, 2021 at 7:42 AM Christophe Leroy <christophe.leroy@csgroup.eu> wrote: > > > > Le 22/03/2021 à 18:53, Andrii Nakryiko a écrit : > > On Mon, Mar 22, 2021 at 9:37 AM Christophe Leroy > > <christophe.leroy@csgroup.eu> wrote: > >> > >> This series implements extended BPF on powerpc32. For the implementation > >> details, see the patch before the last. > >> > >> The following operations are not implemented: > >> > >> case BPF_ALU64 | BPF_DIV | BPF_X: /* dst /= src */ > >> case BPF_ALU64 | BPF_MOD | BPF_X: /* dst %= src */ > >> case BPF_STX | BPF_XADD | BPF_DW: /* *(u64 *)(dst + off) += src */ > >> > >> The following operations are only implemented for power of two constants: > >> > >> case BPF_ALU64 | BPF_MOD | BPF_K: /* dst %= imm */ > >> case BPF_ALU64 | BPF_DIV | BPF_K: /* dst /= imm */ > >> > >> Below are the results on a powerpc 885: > >> - with the patch, with and without bpf_jit_enable > >> - without the patch, with bpf_jit_enable (ie with CBPF) > >> > >> With the patch, with bpf_jit_enable = 1 : > >> > >> [ 60.826529] test_bpf: Summary: 378 PASSED, 0 FAILED, [354/366 JIT'ed] > >> [ 60.832505] test_bpf: test_skb_segment: Summary: 2 PASSED, 0 FAILED > >> > >> With the patch, with bpf_jit_enable = 0 : > >> > >> [ 75.186337] test_bpf: Summary: 378 PASSED, 0 FAILED, [0/366 JIT'ed] > >> [ 75.192325] test_bpf: test_skb_segment: Summary: 2 PASSED, 0 FAILED > >> > >> Without the patch, with bpf_jit_enable = 1 : > >> > >> [ 186.112429] test_bpf: Summary: 371 PASSED, 7 FAILED, [119/366 JIT'ed] > >> > >> Couldn't run test_progs because it doesn't build (clang 11 crashes during the build). > > > > Can you please try checking out the latest clang from sources and use > > that one instead? > > The crash is fixed, it builds one step more, then fails at: > > [root@PC-server-ldb bpf]# make CROSS_COMPILE=ppc-linux- ARCH=powerpc V=1 > /root/gen_ldb/linux-powerpc/tools/testing/selftests/bpf/host-tools/sbin/bpftool gen skeleton > /root/gen_ldb/linux-powerpc/tools/testing/selftests/bpf/atomic_bounds.o > > /root/gen_ldb/linux-powerpc/tools/testing/selftests/bpf/atomic_bounds.skel.h > libbpf: elf: endianness mismatch in atomic_bounds. > Error: failed to open BPF object file: Endian mismatch > > I'm cross-building on x86 for powerpc/32 yeah, I'm not sure selftests/bpf supports cross-compiling. bpftool got some patches recently to enable cross-compiling, but probably not selftests/bpf. > > [root@PC-server-ldb bpf]# file atomic_bounds.o > atomic_bounds.o: ELF 64-bit MSB relocatable, eBPF, version 1 (SYSV), with debug_info, not stripped > > Christophe
On Mon, 22 Mar 2021 16:37:45 +0000 (UTC), Christophe Leroy wrote: > This series implements extended BPF on powerpc32. For the implementation > details, see the patch before the last. > > The following operations are not implemented: > > case BPF_ALU64 | BPF_DIV | BPF_X: /* dst /= src */ > case BPF_ALU64 | BPF_MOD | BPF_X: /* dst %= src */ > case BPF_STX | BPF_XADD | BPF_DW: /* *(u64 *)(dst + off) += src */ > > [...] Applied to powerpc/next. [1/8] powerpc/bpf: Remove classical BPF support for PPC32 https://git.kernel.org/powerpc/c/6944caad78fc4de4ecd0364bbc9715b62b020965 [2/8] powerpc/bpf: Change register numbering for bpf_set/is_seen_register() https://git.kernel.org/powerpc/c/ed573b57e77a7860fe4026e1700faa2f6938caf1 [3/8] powerpc/bpf: Move common helpers into bpf_jit.h https://git.kernel.org/powerpc/c/f1b1583d5faa86cb3dcb7b740594868debad7c30 [4/8] powerpc/bpf: Move common functions into bpf_jit_comp.c https://git.kernel.org/powerpc/c/4ea76e90a97d22f86adbb10044d29d919e620f2e [5/8] powerpc/bpf: Change values of SEEN_ flags https://git.kernel.org/powerpc/c/c426810fcf9f96e3b43d16039e41ecb959f6dc29 [6/8] powerpc/asm: Add some opcodes in asm/ppc-opcode.h for PPC32 eBPF https://git.kernel.org/powerpc/c/355a8d26cd0416e7e764e4db766cf91e773a03e7 [7/8] powerpc/bpf: Implement extended BPF on PPC32 https://git.kernel.org/powerpc/c/51c66ad849a703d9bbfd7704c941827aed0fd9fd [8/8] powerpc/bpf: Reallocate BPF registers to volatile registers when possible on PPC32 https://git.kernel.org/powerpc/c/40272035e1d0edcd515ad45be297c4cce044536d cheers