Re: [PATCH 12/37] xen/x86: decouple nodes_cover_memory from E820 map

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

+x86 maintainers


On Thu, 23 Sep 2021, Wei Chen wrote:
> We will reuse nodes_cover_memory for Arm to check its bootmem
> info. So we introduce two arch helpers to get memory map's
> entry number and specified entry's range:
>     arch_get_memory_bank_number
>     arch_get_memory_bank_range
> 
> Depends above two helpers, we make nodes_cover_memory become
> architecture independent. And the only change from an x86
> perspective is the additional checks:
>   !start || !end
> 
> Signed-off-by: Wei Chen <wei.chen@xxxxxxx>
> ---
>  xen/arch/x86/numa.c        | 18 ++++++++++++++++++
>  xen/arch/x86/srat.c        | 11 ++++-------
>  xen/include/asm-x86/numa.h |  3 +++
>  3 files changed, 25 insertions(+), 7 deletions(-)
> 
> diff --git a/xen/arch/x86/numa.c b/xen/arch/x86/numa.c
> index 6337bbdf31..6bc4ade411 100644
> --- a/xen/arch/x86/numa.c
> +++ b/xen/arch/x86/numa.c
> @@ -378,6 +378,24 @@ unsigned int arch_have_default_dmazone(void)
>      return ( num_online_nodes() > 1 ) ? 1 : 0;
>  }
>  
> +uint32_t __init arch_meminfo_get_nr_bank(void)
> +{
> +     return e820.nr_map;
> +}
> +
> +int __init arch_meminfo_get_ram_bank_range(uint32_t bank,
> +     paddr_t *start, paddr_t *end)
> +{
> +     if (e820.map[bank].type != E820_RAM || !start || !end) {
> +             return -1;
> +     }
> +
> +     *start = e820.map[bank].addr;
> +     *end = e820.map[bank].addr + e820.map[bank].size;
> +
> +     return 0;
> +}
> +
>  static void dump_numa(unsigned char key)
>  {
>      s_time_t now = NOW();
> diff --git a/xen/arch/x86/srat.c b/xen/arch/x86/srat.c
> index 18bc6b19bb..aa07a7e975 100644
> --- a/xen/arch/x86/srat.c
> +++ b/xen/arch/x86/srat.c
> @@ -419,17 +419,14 @@ acpi_numa_memory_affinity_init(const struct 
> acpi_srat_mem_affinity *ma)
>  static int __init nodes_cover_memory(void)
>  {
>       int i;
> +     uint32_t nr_banks = arch_meminfo_get_nr_bank();
>  
> -     for (i = 0; i < e820.nr_map; i++) {
> +     for (i = 0; i < nr_banks; i++) {
>               int j, found;
>               paddr_t start, end;
>  
> -             if (e820.map[i].type != E820_RAM) {
> +             if (arch_meminfo_get_ram_bank_range(i, &start, &end))
>                       continue;
> -             }
> -
> -             start = e820.map[i].addr;
> -             end = e820.map[i].addr + e820.map[i].size;
>  
>               do {
>                       found = 0;
> @@ -448,7 +445,7 @@ static int __init nodes_cover_memory(void)
>               } while (found && start < end);
>  
>               if (start < end) {
> -                     printk(KERN_ERR "SRAT: No PXM for e820 range: "
> +                     printk(KERN_ERR "SRAT: No NODE for memory map range: "
>                               "%"PRIpaddr" - %"PRIpaddr"\n", start, end);
>                       return 0;
>               }
> diff --git a/xen/include/asm-x86/numa.h b/xen/include/asm-x86/numa.h
> index 5772a70665..78e044a390 100644
> --- a/xen/include/asm-x86/numa.h
> +++ b/xen/include/asm-x86/numa.h
> @@ -82,5 +82,8 @@ void srat_parse_regions(paddr_t addr);
>  extern u8 __node_distance(nodeid_t a, nodeid_t b);
>  unsigned int arch_get_dma_bitsize(void);
>  unsigned int arch_have_default_dmazone(void);
> +extern uint32_t arch_meminfo_get_nr_bank(void);
> +extern int arch_meminfo_get_ram_bank_range(uint32_t bank,
> +    paddr_t *start, paddr_t *end);
>  
>  #endif
> -- 
> 2.25.1
>