[PATCH net-next V2] ARM: net: support BPF_ALU | BPF_MOD instructions in the BPF JIT.
alexei.starovoitov at gmail.com
Fri Oct 2 08:25:20 PDT 2015
On Fri, Oct 02, 2015 at 05:06:47PM +0200, Nicolas Schichan wrote:
> For ARMv7 with UDIV instruction support, generate an UDIV instruction
> followed by an MLS instruction.
> For other ARM variants, generate code calling a C wrapper similar to
> the jit_udiv() function used for BPF_ALU | BPF_DIV instructions.
> Some performance numbers reported by the test_bpf module (the duration
> per filter run is reported in nanoseconds, between "jitted:<x>" and
> ARMv7 QEMU nojit: test_bpf: #3 DIV_MOD_KX jited:0 2196 PASS
> ARMv7 QEMU jit: test_bpf: #3 DIV_MOD_KX jited:1 104 PASS
> ARMv5 QEMU nojit: test_bpf: #3 DIV_MOD_KX jited:0 2176 PASS
> ARMv5 QEMU jit: test_bpf: #3 DIV_MOD_KX jited:1 1104 PASS
> ARMv5 kirkwood nojit: test_bpf: #3 DIV_MOD_KX jited:0 1103 PASS
> ARMv5 kirkwood jit: test_bpf: #3 DIV_MOD_KX jited:1 311 PASS
> Signed-off-by: Nicolas Schichan <nschichan at freebox.fr>
run-time check for zero is there, so looks good to me
Acked-by: Alexei Starovoitov <ast at kernel.org>
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