[PATCH 2/3] RISC-V: K210 defconfigs: Drop redundant MEMBARRIER=n

Palmer Dabbelt palmer at rivosinc.com
Wed Mar 30 19:16:22 PDT 2022


On Wed, 30 Mar 2022 17:26:45 PDT (-0700), damien.lemoal at opensource.wdc.com wrote:
> On 3/31/22 08:47, Palmer Dabbelt wrote:
>> From: Palmer Dabbelt <palmer at rivosinc.com>
>>
>> As of 93917ad50972 ("RISC-V: Add support for restartable sequence") we
>> have support for restartable sequences, which default to enabled.  These
>> select MEMBARRIER, so disabling it is now redundant.
>>
>> Signed-off-by: Palmer Dabbelt <palmer at rivosinc.com>
>>
>> ---
>>
>> I'm not actually sure this is the right way to go: presumably the K210
>> defconfigs had MEMBARRIER=n for a reason (maybe just size?), so we might
>> actually want to move to RSEQ=n instead?  As usual: I don't test on the
>> K210, so I'm not exactly sure what the constraints are.
>
> Not sure either. It is like this now because I think this was the default
> at the time the config was created.
>
> Niklas,
>
> Can you test this please ?

Thanks.  I'm OK either way, I guess I'd learn towards turning on the 
features if they work/fit.  I'll hold off on merging this one for a bit, 
I don't see any rush (it's just a defconfig) and if what was there is 
broken then we can take it as a fix.  Otherwise it'll just get rolled up 
into the next round of these, which I'll hopefully remember to do 
earlier next time.

>
>> ---
>>  arch/riscv/configs/nommu_k210_defconfig        | 1 -
>>  arch/riscv/configs/nommu_k210_sdcard_defconfig | 1 -
>>  arch/riscv/configs/nommu_virt_defconfig        | 1 -
>>  3 files changed, 3 deletions(-)
>>
>> diff --git a/arch/riscv/configs/nommu_k210_defconfig b/arch/riscv/configs/nommu_k210_defconfig
>> index 3f42ed87dde8..2438fa39f8ae 100644
>> --- a/arch/riscv/configs/nommu_k210_defconfig
>> +++ b/arch/riscv/configs/nommu_k210_defconfig
>> @@ -21,7 +21,6 @@ CONFIG_CC_OPTIMIZE_FOR_SIZE=y
>>  # CONFIG_AIO is not set
>>  # CONFIG_IO_URING is not set
>>  # CONFIG_ADVISE_SYSCALLS is not set
>> -# CONFIG_MEMBARRIER is not set
>>  # CONFIG_KALLSYMS is not set
>>  CONFIG_EMBEDDED=y
>>  # CONFIG_VM_EVENT_COUNTERS is not set
>> diff --git a/arch/riscv/configs/nommu_k210_sdcard_defconfig b/arch/riscv/configs/nommu_k210_sdcard_defconfig
>> index af64b95e88cc..9a133e63ae5b 100644
>> --- a/arch/riscv/configs/nommu_k210_sdcard_defconfig
>> +++ b/arch/riscv/configs/nommu_k210_sdcard_defconfig
>> @@ -13,7 +13,6 @@ CONFIG_CC_OPTIMIZE_FOR_SIZE=y
>>  # CONFIG_AIO is not set
>>  # CONFIG_IO_URING is not set
>>  # CONFIG_ADVISE_SYSCALLS is not set
>> -# CONFIG_MEMBARRIER is not set
>>  # CONFIG_KALLSYMS is not set
>>  CONFIG_EMBEDDED=y
>>  # CONFIG_VM_EVENT_COUNTERS is not set
>> diff --git a/arch/riscv/configs/nommu_virt_defconfig b/arch/riscv/configs/nommu_virt_defconfig
>> index e1c9864b6237..5269fbb6b4fc 100644
>> --- a/arch/riscv/configs/nommu_virt_defconfig
>> +++ b/arch/riscv/configs/nommu_virt_defconfig
>> @@ -19,7 +19,6 @@ CONFIG_EXPERT=y
>>  # CONFIG_AIO is not set
>>  # CONFIG_IO_URING is not set
>>  # CONFIG_ADVISE_SYSCALLS is not set
>> -# CONFIG_MEMBARRIER is not set
>>  # CONFIG_KALLSYMS is not set
>>  # CONFIG_VM_EVENT_COUNTERS is not set
>>  # CONFIG_COMPAT_BRK is not set



More information about the linux-riscv mailing list