Re: [PATCH v4 15/18] xen/riscv: implement put_page()

[Jan Beulich <jbeulich@xxxxxxxx>]

On 17.09.2025 23:55, Oleksii Kurochko wrote:
> Implement put_page(), as it will be used by  p2m_put_*-related code.
> 
> Although CONFIG_STATIC_MEMORY has not yet been introduced for RISC-V,
> a stub for PGC_static is added to avoid cluttering the code of
> put_page() with #ifdefs.
> 
> Signed-off-by: Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>

Acked-by: Jan Beulich <jbeulich@xxxxxxxx>
with ...

> @@ -627,3 +622,23 @@ void flush_page_to_ram(unsigned long mfn, bool 
> sync_icache)
>      if ( sync_icache )
>          invalidate_icache();
>  }
> +
> +void put_page(struct page_info *page)
> +{
> +    unsigned long nx, x, y = page->count_info;
> +
> +    do {
> +        ASSERT((y & PGC_count_mask) >= 1);
> +        x  = y;
> +        nx = x - 1;
> +    }
> +    while ( unlikely((y = cmpxchg(&page->count_info, x, nx)) != x) );

... style corrected here (just like for "do" the figure brace here also doesn't
want to go onto its own line).

Jan