This memory barrier is not needed and not documented so simply remove
it.

Suggested-by: Andrea Parri <andrea@rivosinc.com>
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Reviewed-by: Andrea Parri <parri.andrea@gmail.com>
---
 arch/riscv/kernel/patch.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/arch/riscv/kernel/patch.c b/arch/riscv/kernel/patch.c
index 37e87fdcf6a0..0b5c16dfe3f4 100644
--- a/arch/riscv/kernel/patch.c
+++ b/arch/riscv/kernel/patch.c
@@ -239,7 +239,6 @@ static int patch_text_cb(void *data)
 	} else {
 		while (atomic_read(&patch->cpu_count) <= num_online_cpus())
 			cpu_relax();
-		smp_mb();
 	}
 
 	return ret;
-- 
2.39.2

On Thu, Feb 29, 2024 at 01:10:55PM +0100, Alexandre Ghiti wrote:
> This memory barrier is not needed and not documented so simply remove
> it.

This looks like it should be patch 2 in the series, not patch 1, as it
is cleanup rather than a fix that needs backporting.

> 
> Suggested-by: Andrea Parri <andrea@rivosinc.com>
> Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
> Reviewed-by: Andrea Parri <parri.andrea@gmail.com>
> ---
>  arch/riscv/kernel/patch.c | 1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/arch/riscv/kernel/patch.c b/arch/riscv/kernel/patch.c
> index 37e87fdcf6a0..0b5c16dfe3f4 100644
> --- a/arch/riscv/kernel/patch.c
> +++ b/arch/riscv/kernel/patch.c
> @@ -239,7 +239,6 @@ static int patch_text_cb(void *data)
>  	} else {
>  		while (atomic_read(&patch->cpu_count) <= num_online_cpus())
>  			cpu_relax();
> -		smp_mb();
>  	}
>  
>  	return ret;
> -- 
> 2.39.2
> 
> 
> _______________________________________________
> linux-riscv mailing list
> linux-riscv@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-riscv

On Mon, 04 Mar 2024 11:25:33 PST (-0800), Conor Dooley wrote:
> On Thu, Feb 29, 2024 at 01:10:55PM +0100, Alexandre Ghiti wrote:
>> This memory barrier is not needed and not documented so simply remove
>> it.
>
> This looks like it should be patch 2 in the series, not patch 1, as it
> is cleanup rather than a fix that needs backporting.

IIUC neither is actually a fix, as the other is only exposed by the 
IOMMU driver and that's not upstream yet.  So I'm just going to pick 
these up on for-next.

>
>> 
>> Suggested-by: Andrea Parri <andrea@rivosinc.com>
>> Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
>> Reviewed-by: Andrea Parri <parri.andrea@gmail.com>
>> ---
>>  arch/riscv/kernel/patch.c | 1 -
>>  1 file changed, 1 deletion(-)
>> 
>> diff --git a/arch/riscv/kernel/patch.c b/arch/riscv/kernel/patch.c
>> index 37e87fdcf6a0..0b5c16dfe3f4 100644
>> --- a/arch/riscv/kernel/patch.c
>> +++ b/arch/riscv/kernel/patch.c
>> @@ -239,7 +239,6 @@ static int patch_text_cb(void *data)
>>  	} else {
>>  		while (atomic_read(&patch->cpu_count) <= num_online_cpus())
>>  			cpu_relax();
>> -		smp_mb();
>>  	}
>>  
>>  	return ret;
>> -- 
>> 2.39.2
>> 
>> 
>> _______________________________________________
>> linux-riscv mailing list
>> linux-riscv@lists.infradead.org
>> http://lists.infradead.org/mailman/listinfo/linux-riscv