Re: [Qemu-devel] [PATCH 7/8] tcg: Extract removing of jumps to TB from tb_phys_invalidate()

["Alex Bennée" <alex.bennee@linaro.org>]

sergey.fedorov@linaro.org writes:

> From: Sergey Fedorov <serge.fdrv@gmail.com>
>
> Move the code for removing jumps to a TB out of tb_phys_invalidate() to
> a separate static inline function tb_jmp_unlink(). This simplifies
> tb_phys_invalidate() and improves code structure.
>
> Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com>
> Signed-off-by: Sergey Fedorov <sergey.fedorov@linaro.org>

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>

> ---
>  translate-all.c | 44 ++++++++++++++++++++++++++------------------
>  1 file changed, 26 insertions(+), 18 deletions(-)
>
> diff --git a/translate-all.c b/translate-all.c
> index 28154ed75888..8b4bfa713bf7 100644
> --- a/translate-all.c
> +++ b/translate-all.c
> @@ -959,14 +959,37 @@ static inline void tb_reset_jump(TranslationBlock *tb, int n)
>      tb_set_jmp_target(tb, n, addr);
>  }
>
> +/* remove any jumps to the TB */
> +static inline void tb_jmp_unlink(TranslationBlock *tb)
> +{
> +    uintptr_t tb1, tb2;
> +    unsigned int n1;
> +
> +    tb1 = tb->jmp_list_first;
> +    for (;;) {
> +        TranslationBlock *tmp_tb;
> +        n1 = tb1 & 3;
> +        if (n1 == 2) {
> +            break;
> +        }
> +        tmp_tb = (TranslationBlock *)(tb1 & ~3);
> +        tb2 = tmp_tb->jmp_list_next[n1];
> +        tb_reset_jump(tmp_tb, n1);
> +        tmp_tb->jmp_list_next[n1] = (uintptr_t)NULL;
> +        tb1 = tb2;
> +    }
> +
> +    assert(((uintptr_t)tb & 3) == 0);
> +    tb->jmp_list_first = (uintptr_t)tb | 2; /* fail safe */
> +}
> +
>  /* invalidate one TB */
>  void tb_phys_invalidate(TranslationBlock *tb, tb_page_addr_t page_addr)
>  {
>      CPUState *cpu;
>      PageDesc *p;
> -    unsigned int h, n1;
> +    unsigned int h;
>      tb_page_addr_t phys_pc;
> -    uintptr_t tb1, tb2;
>
>      /* remove the TB from the hash list */
>      phys_pc = tb->page_addr[0] + (tb->pc & ~TARGET_PAGE_MASK);
> @@ -1000,22 +1023,7 @@ void tb_phys_invalidate(TranslationBlock *tb, tb_page_addr_t page_addr)
>      tb_remove_from_jmp_list(tb, 1);
>
>      /* suppress any remaining jumps to this TB */
> -    tb1 = tb->jmp_list_first;
> -    for (;;) {
> -        TranslationBlock *tmp_tb;
> -        n1 = tb1 & 3;
> -        if (n1 == 2) {
> -            break;
> -        }
> -        tmp_tb = (TranslationBlock *)(tb1 & ~3);
> -        tb2 = tmp_tb->jmp_list_next[n1];
> -        tb_reset_jump(tmp_tb, n1);
> -        tmp_tb->jmp_list_next[n1] = (uintptr_t)NULL;
> -        tb1 = tb2;
> -    }
> -
> -    assert(((uintptr_t)tb & 3) == 0);
> -    tb->jmp_list_first = (uintptr_t)tb | 2; /* fail safe */
> +    tb_jmp_unlink(tb);
>
>      tcg_ctx.tb_ctx.tb_phys_invalidate_count++;
>  }


--
Alex Bennée