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Re: [PATCH v2 net-next] bpf: arm64: remove callee-save registers use for tmp registers

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On 05/17/2016 01:36 AM, Yang Shi wrote:
> In the current implementation of ARM64 eBPF JIT, R23 and R24 are used for
> tmp registers, which are callee-saved registers. This leads to variable size
> of JIT prologue and epilogue. The latest blinding constant change prefers to
> constant size of prologue and epilogue. AAPCS reserves R9 ~ R15 for temp
> registers which not need to be saved/restored during function call. So, replace
> R23 and R24 to R10 and R11, and remove tmp_used flag to save 2 instructions for
> some jited BPF program.
>
> CC: Daniel Borkmann <daniel@iogearbox.net>
> Acked-by: Zi Shen Lim <zlim.lnx@gmail.com>
> Signed-off-by: Yang Shi <yang.shi@linaro.org>

LGTM, thanks!

Acked-by: Daniel Borkmann <daniel@iogearbox.net>

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[PATCH v2 net-next] bpf: arm64: remove callee-save registers use for tmp registers Yang Shi <yang.shi@linaro.org> - 2016-05-17 02:10 +0200
  Re: [PATCH v2 net-next] bpf: arm64: remove callee-save registers use  for tmp registers Catalin Marinas <catalin.marinas@arm.com> - 2016-05-17 13:20 +0200
  Re: [PATCH v2 net-next] bpf: arm64: remove callee-save registers  use for tmp registers Daniel Borkmann <daniel@iogearbox.net> - 2016-05-17 14:00 +0200
  Re: [PATCH v2 net-next] bpf: arm64: remove callee-save registers  use for tmp registers David Miller <davem@davemloft.net> - 2016-05-17 20:10 +0200

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