[PATCH 3/6] lib: sbi: Optimize fifo enqueue/dequeue for basic data types

[Himanshu Chauhan]

On Fri, Jul 5, 2024 at 12:45 PM Anup Patel <apatel at ventanamicro.com> wrote:
>
> Don't use sbi_memcpy() for basic data types in fifo enqueue/dequeue
> instead use direct type-cast and assignment.
>
> Signed-off-by: Anup Patel <apatel at ventanamicro.com>
> ---
>  lib/sbi/sbi_fifo.c | 43 ++++++++++++++++++++++++++++++++++++++++---
>  1 file changed, 40 insertions(+), 3 deletions(-)
>
> diff --git a/lib/sbi/sbi_fifo.c b/lib/sbi/sbi_fifo.c
> index 72c6d39..9199a30 100644
> --- a/lib/sbi/sbi_fifo.c
> +++ b/lib/sbi/sbi_fifo.c
> @@ -66,7 +66,26 @@ static inline void  __sbi_fifo_enqueue(struct sbi_fifo *fifo, void *data)
>         if (head >= fifo->num_entries)
>                 head = head - fifo->num_entries;
>
> -       sbi_memcpy((char *)fifo->queue + head * fifo->entry_size, data, fifo->entry_size);
> +       switch (fifo->entry_size) {
> +       case 1:
> +               *(char *)(fifo->queue + head * fifo->entry_size) = *(char *)data;
> +               break;
> +       case 2:
> +               *(u16 *)(fifo->queue + head * fifo->entry_size) = *(u16 *)data;
> +               break;
> +       case 4:
> +               *(u32 *)(fifo->queue + head * fifo->entry_size) = *(u32 *)data;
> +               break;
> +#if __riscv_xlen > 32
> +       case 8:
> +               *(u64 *)(fifo->queue + head * fifo->entry_size) = *(u64 *)data;
> +               break;
> +#endif
> +       default:
> +               sbi_memcpy(fifo->queue + head * fifo->entry_size,
> +                          data, fifo->entry_size);
> +               break;
> +       }
>
>         fifo->avail++;
>  }
> @@ -184,8 +203,26 @@ int sbi_fifo_dequeue(struct sbi_fifo *fifo, void *data)
>                 return SBI_ENOENT;
>         }
>
> -       sbi_memcpy(data, (char *)fifo->queue + (u32)fifo->tail * fifo->entry_size,
> -              fifo->entry_size);
> +       switch (fifo->entry_size) {
> +       case 1:
> +               *(char *)data = *(char *)(fifo->queue + (u32)fifo->tail * fifo->entry_size);
> +               break;
> +       case 2:
> +               *(u16 *)data = *(u16 *)(fifo->queue + (u32)fifo->tail * fifo->entry_size);
> +               break;
> +       case 4:
> +               *(u32 *)data = *(u32 *)(fifo->queue + (u32)fifo->tail * fifo->entry_size);
> +               break;
> +#if __riscv_xlen > 32
> +       case 8:
> +               *(u64 *)data = *(u64 *)(fifo->queue + (u32)fifo->tail * fifo->entry_size);
> +               break;
> +#endif
> +       default:
> +               sbi_memcpy(data, fifo->queue + (u32)fifo->tail * fifo->entry_size,
> +                          fifo->entry_size);
> +               break;
> +       }
>
>         fifo->avail--;
>         fifo->tail++;
> --
> 2.34.1
>
 LGTM

Reviewed-By: Himanshu Chauhan <hchauhan at ventanamicro.com>

>
>
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