Re: [PATCH v8 03/46] x86, mm: Move down find_early_table_space()

[Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>]

On Fri, Nov 16, 2012 at 07:38:40PM -0800, Yinghai Lu wrote:
> It will need to call split_mem_range().

.. which implies that it needs to call it now, but I could
not find the call in your patch. Then realized you meant
to do that in the further patches. To avoid this confusion
I would recommend you add " in further patch
titled XYZ."


> Move it down after that to avoid extra declaration.
> 
> Signed-off-by: Yinghai Lu <yinghai@kernel.org>
> ---
>  arch/x86/mm/init.c |  117 ++++++++++++++++++++++++++--------------------------
>  1 files changed, 59 insertions(+), 58 deletions(-)
> 
> diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
> index 6368b86..701abbc 100644
> --- a/arch/x86/mm/init.c
> +++ b/arch/x86/mm/init.c
> @@ -36,64 +36,6 @@ struct map_range {
>  };
>  
>  static int page_size_mask;
> -/*
> - * First calculate space needed for kernel direct mapping page tables to cover
> - * mr[0].start to mr[nr_range - 1].end, while accounting for possible 2M and 1GB
> - * pages. Then find enough contiguous space for those page tables.
> - */
> -static void __init find_early_table_space(struct map_range *mr, int nr_range)
> -{
> -	int i;
> -	unsigned long puds = 0, pmds = 0, ptes = 0, tables;
> -	unsigned long start = 0, good_end;
> -	phys_addr_t base;
> -
> -	for (i = 0; i < nr_range; i++) {
> -		unsigned long range, extra;
> -
> -		range = mr[i].end - mr[i].start;
> -		puds += (range + PUD_SIZE - 1) >> PUD_SHIFT;
> -
> -		if (mr[i].page_size_mask & (1 << PG_LEVEL_1G)) {
> -			extra = range - ((range >> PUD_SHIFT) << PUD_SHIFT);
> -			pmds += (extra + PMD_SIZE - 1) >> PMD_SHIFT;
> -		} else {
> -			pmds += (range + PMD_SIZE - 1) >> PMD_SHIFT;
> -		}
> -
> -		if (mr[i].page_size_mask & (1 << PG_LEVEL_2M)) {
> -			extra = range - ((range >> PMD_SHIFT) << PMD_SHIFT);
> -#ifdef CONFIG_X86_32
> -			extra += PMD_SIZE;
> -#endif
> -			ptes += (extra + PAGE_SIZE - 1) >> PAGE_SHIFT;
> -		} else {
> -			ptes += (range + PAGE_SIZE - 1) >> PAGE_SHIFT;
> -		}
> -	}
> -
> -	tables = roundup(puds * sizeof(pud_t), PAGE_SIZE);
> -	tables += roundup(pmds * sizeof(pmd_t), PAGE_SIZE);
> -	tables += roundup(ptes * sizeof(pte_t), PAGE_SIZE);
> -
> -#ifdef CONFIG_X86_32
> -	/* for fixmap */
> -	tables += roundup(__end_of_fixed_addresses * sizeof(pte_t), PAGE_SIZE);
> -#endif
> -	good_end = max_pfn_mapped << PAGE_SHIFT;
> -
> -	base = memblock_find_in_range(start, good_end, tables, PAGE_SIZE);
> -	if (!base)
> -		panic("Cannot find space for the kernel page tables");
> -
> -	pgt_buf_start = base >> PAGE_SHIFT;
> -	pgt_buf_end = pgt_buf_start;
> -	pgt_buf_top = pgt_buf_start + (tables >> PAGE_SHIFT);
> -
> -	printk(KERN_DEBUG "kernel direct mapping tables up to %#lx @ [mem %#010lx-%#010lx]\n",
> -		mr[nr_range - 1].end - 1, pgt_buf_start << PAGE_SHIFT,
> -		(pgt_buf_top << PAGE_SHIFT) - 1);
> -}
>  
>  void probe_page_size_mask(void)
>  {
> @@ -250,6 +192,65 @@ static int __meminit split_mem_range(struct map_range *mr, int nr_range,
>  }
>  
>  /*
> + * First calculate space needed for kernel direct mapping page tables to cover
> + * mr[0].start to mr[nr_range - 1].end, while accounting for possible 2M and 1GB
> + * pages. Then find enough contiguous space for those page tables.
> + */
> +static void __init find_early_table_space(struct map_range *mr, int nr_range)
> +{
> +	int i;
> +	unsigned long puds = 0, pmds = 0, ptes = 0, tables;
> +	unsigned long start = 0, good_end;
> +	phys_addr_t base;
> +
> +	for (i = 0; i < nr_range; i++) {
> +		unsigned long range, extra;
> +
> +		range = mr[i].end - mr[i].start;
> +		puds += (range + PUD_SIZE - 1) >> PUD_SHIFT;
> +
> +		if (mr[i].page_size_mask & (1 << PG_LEVEL_1G)) {
> +			extra = range - ((range >> PUD_SHIFT) << PUD_SHIFT);
> +			pmds += (extra + PMD_SIZE - 1) >> PMD_SHIFT;
> +		} else {
> +			pmds += (range + PMD_SIZE - 1) >> PMD_SHIFT;
> +		}
> +
> +		if (mr[i].page_size_mask & (1 << PG_LEVEL_2M)) {
> +			extra = range - ((range >> PMD_SHIFT) << PMD_SHIFT);
> +#ifdef CONFIG_X86_32
> +			extra += PMD_SIZE;
> +#endif
> +			ptes += (extra + PAGE_SIZE - 1) >> PAGE_SHIFT;
> +		} else {
> +			ptes += (range + PAGE_SIZE - 1) >> PAGE_SHIFT;
> +		}
> +	}
> +
> +	tables = roundup(puds * sizeof(pud_t), PAGE_SIZE);
> +	tables += roundup(pmds * sizeof(pmd_t), PAGE_SIZE);
> +	tables += roundup(ptes * sizeof(pte_t), PAGE_SIZE);
> +
> +#ifdef CONFIG_X86_32
> +	/* for fixmap */
> +	tables += roundup(__end_of_fixed_addresses * sizeof(pte_t), PAGE_SIZE);
> +#endif
> +	good_end = max_pfn_mapped << PAGE_SHIFT;
> +
> +	base = memblock_find_in_range(start, good_end, tables, PAGE_SIZE);
> +	if (!base)
> +		panic("Cannot find space for the kernel page tables");
> +
> +	pgt_buf_start = base >> PAGE_SHIFT;
> +	pgt_buf_end = pgt_buf_start;
> +	pgt_buf_top = pgt_buf_start + (tables >> PAGE_SHIFT);
> +
> +	printk(KERN_DEBUG "kernel direct mapping tables up to %#lx @ [mem %#010lx-%#010lx]\n",
> +		mr[nr_range - 1].end - 1, pgt_buf_start << PAGE_SHIFT,
> +		(pgt_buf_top << PAGE_SHIFT) - 1);
> +}
> +
> +/*
>   * Setup the direct mapping of the physical memory at PAGE_OFFSET.
>   * This runs before bootmem is initialized and gets pages directly from
>   * the physical memory. To access them they are temporarily mapped.
> -- 
> 1.7.7