Re: [PATCH 2/2] MIPS: ebpf jit: Implement R4000 workarounds

From: Jiaxun Yang
Date: Mon Feb 27 2023 - 10:47:34 EST




在2023年2月27日二月 下午3:18,Maciej W. Rozycki写道:
> On Mon, 27 Feb 2023, Johan Almbladh wrote:
>
>> > > R4000 is a 64-bit CPU, so the 32-bit JIT implementation will not be
>> > > used. From the Makefile:
>> > >
>> > > ifeq ($(CONFIG_32BIT),y)
>> > > obj-$(CONFIG_BPF_JIT) += bpf_jit_comp32.o
>> > > else
>> > > obj-$(CONFIG_BPF_JIT) += bpf_jit_comp64.o
>> > > endif
>> >
>> > It’s common practice to run 32-bit kernel on R4000 based systems to save some memory :-)
>>
>> Ok, I understand.
>
> Likewise:
>
> select CPU_R4000_WORKAROUNDS if 64BIT
> select CPU_R4400_WORKAROUNDS if 64BIT
>
> This only applies to 64-bit operations, which are not used in 32-bit code
> (one reason why these early silicon revisions were originally used with
> 32-bit software only).

Thanks for the info.
Will drop 32bit part from both patch.

>
> Maciej

--
- Jiaxun