Re: [PATCH v3 07/17] riscv: misaligned: move emulated access uniformity check in a function

Andrew Jones
2025-03-13T13:07:20Z

On Mon, Mar 10, 2025 at 04:12:14PM +0100, Clément Léger wrote:
> Split the code that check for the uniformity of misaligned accesses
> performance on all cpus from check_unaligned_access_emulated_all_cpus()
> to its own function which will be used for delegation check. No
> functional changes intended.
>
> Signed-off-by: Clément Léger <cleger@rivosinc.com>
> ---
> arch/riscv/kernel/traps_misaligned.c | 18 +++++++++++++-----
> 1 file changed, 13 insertions(+), 5 deletions(-)
>
> diff --git a/arch/riscv/kernel/traps_misaligned.c b/arch/riscv/kernel/traps_misaligned.c
> index 7fe25adf2539..db31966a834e 100644
> --- a/arch/riscv/kernel/traps_misaligned.c
> +++ b/arch/riscv/kernel/traps_misaligned.c
> @@ -673,10 +673,20 @@ static int cpu_online_check_unaligned_access_emulated(unsigned int cpu)
> return 0;
> }
>
> -bool check_unaligned_access_emulated_all_cpus(void)
> +static bool all_cpus_unaligned_scalar_access_emulated(void)
> {
> int cpu;
>
> + for_each_online_cpu(cpu)
> + if (per_cpu(misaligned_access_speed, cpu) !=
> + RISCV_HWPROBE_MISALIGNED_SCALAR_EMULATED)
> + return false;
> +
> + return true;
> +}
> +
> +bool check_unaligned_access_emulated_all_cpus(void)
> +{
> /*
> * We can only support PR_UNALIGN controls if all CPUs have misaligned
> * accesses emulated since tasks requesting such control can run on any
> @@ -684,10 +694,8 @@ bool check_unaligned_access_emulated_all_cpus(void)
> */
> on_each_cpu(check_unaligned_access_emulated, NULL, 1);
>
> - for_each_online_cpu(cpu)
> - if (per_cpu(misaligned_access_speed, cpu)
> - != RISCV_HWPROBE_MISALIGNED_SCALAR_EMULATED)
> - return false;
> + if (!all_cpus_unaligned_scalar_access_emulated())
> + return false;
>
> unaligned_ctl = true;
> return true;
> --
> 2.47.2
>

Reviewed-by: Andrew Jones <ajones@ventanamicro.com>