Re: [PATCH v2 13/13] riscv: remove riscv_isa_ext_keys[] array and related usage

Guo Ren
2022-12-05T00:53:55Z

On Mon, Dec 5, 2022 at 1:57 AM Jisheng Zhang <jszhang@kernel.org> wrote:
>
> All users have switched to riscv_has_extension_*, removed unused
> definitions, vars and related setting code.
>
> Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
> Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
> Reviewed-by: Heiko Stuebner <heiko@sntech.de>
> ---
> arch/riscv/include/asm/hwcap.h | 30 ------------------------------
> arch/riscv/kernel/cpufeature.c | 9 ---------
> 2 files changed, 39 deletions(-)
>
> diff --git a/arch/riscv/include/asm/hwcap.h b/arch/riscv/include/asm/hwcap.h
> index e2d3f6df7701..be00a4337578 100644
> --- a/arch/riscv/include/asm/hwcap.h
> +++ b/arch/riscv/include/asm/hwcap.h
> @@ -60,18 +60,6 @@ enum {
>
> extern unsigned long elf_hwcap;
>
> -/*
> - * This enum represents the logical ID for each RISC-V ISA extension static
> - * keys. We can use static key to optimize code path if some ISA extensions
> - * are available.
> - */
> -enum riscv_isa_ext_key {
> - RISCV_ISA_EXT_KEY_FPU, /* For 'F' and 'D' */
> - RISCV_ISA_EXT_KEY_ZIHINTPAUSE,
> - RISCV_ISA_EXT_KEY_SVINVAL,
> - RISCV_ISA_EXT_KEY_MAX,
> -};
> -
> struct riscv_isa_ext_data {
> /* Name of the extension displayed to userspace via /proc/cpuinfo */
> char uprop[RISCV_ISA_EXT_NAME_LEN_MAX];
> @@ -79,24 +67,6 @@ struct riscv_isa_ext_data {
> unsigned int isa_ext_id;
> };
>
> -extern struct static_key_false riscv_isa_ext_keys[RISCV_ISA_EXT_KEY_MAX];
> -
> -static __always_inline int riscv_isa_ext2key(int num)
> -{
> - switch (num) {
> - case RISCV_ISA_EXT_f:
> - return RISCV_ISA_EXT_KEY_FPU;
> - case RISCV_ISA_EXT_d:
> - return RISCV_ISA_EXT_KEY_FPU;
> - case RISCV_ISA_EXT_ZIHINTPAUSE:
> - return RISCV_ISA_EXT_KEY_ZIHINTPAUSE;
> - case RISCV_ISA_EXT_SVINVAL:
> - return RISCV_ISA_EXT_KEY_SVINVAL;
> - default:
> - return -EINVAL;
> - }
> -}
> -
Reviewed-by: Guo Ren <guoren@kernel.org>

> static __always_inline bool
> riscv_has_extension_likely(const unsigned long ext)
> {
> diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
> index adeac90b1d8e..3240a2915bf1 100644
> --- a/arch/riscv/kernel/cpufeature.c
> +++ b/arch/riscv/kernel/cpufeature.c
> @@ -28,9 +28,6 @@ unsigned long elf_hwcap __read_mostly;
> /* Host ISA bitmap */
> static DECLARE_BITMAP(riscv_isa, RISCV_ISA_EXT_MAX) __read_mostly;
>
> -DEFINE_STATIC_KEY_ARRAY_FALSE(riscv_isa_ext_keys, RISCV_ISA_EXT_KEY_MAX);
> -EXPORT_SYMBOL(riscv_isa_ext_keys);
> -
> /**
> * riscv_isa_extension_base() - Get base extension word
> *
> @@ -243,12 +240,6 @@ void __init riscv_fill_hwcap(void)
> if (elf_hwcap & BIT_MASK(i))
> print_str[j++] = (char)('a' + i);
> pr_info("riscv: ELF capabilities %s\n", print_str);
> -
> - for_each_set_bit(i, riscv_isa, RISCV_ISA_EXT_MAX) {
> - j = riscv_isa_ext2key(i);
> - if (j >= 0)
> - static_branch_enable(&riscv_isa_ext_keys[j]);
> - }
Reviewed-by: Guo Ren <guoren@kernel.org>

> }
>
> #ifdef CONFIG_RISCV_ALTERNATIVE
> --
> 2.37.2
>

--
Best Regards
Guo Ren