Re: [PATCH v3] mm: page_alloc: Add debug log in free_reserved_area for static memory

From: David Hildenbrand
Date: Thu Oct 14 2021 - 03:22:56 EST


On 14.10.21 09:12, Faiyaz Mohammed wrote:
> For INITRD and initmem memory is reserved through "memblock_reserve"
> during boot up but it is free via "free_reserved_area" instead
> of "memblock_free".
> For example:
> [ 0.294848] Freeing initrd memory: 12K.
> [ 0.696688] Freeing unused kernel memory: 4096K.
>
> To get the start and end address of the above freed memory and to account
> proper memblock added pr_debug log in "free_reserved_area".
> After adding log:
> [ 0.294837] 0x00000083600000-0x00000083603000 free_initrd_mem+0x20/0x28
> [ 0.294848] Freeing initrd memory: 12K.
> [ 0.695246] 0x00000081600000-0x00000081a00000 free_initmem+0x70/0xc8
> [ 0.696688] Freeing unused kernel memory: 4096K.
>
> Signed-off-by: Faiyaz Mohammed <faiyazm@xxxxxxxxxxxxxx>
> ---
> changes in v3:
> - Update the format specifier.
> changes in v2:
> - To avoid confusion, remove the memblock_dbg print and drop the
> memblock_free string, now using pr_debug to print the address ranges.
>
> mm/page_alloc.c | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index b37435c..13adda5 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -8097,6 +8097,8 @@ EXPORT_SYMBOL(adjust_managed_page_count);
>
> unsigned long free_reserved_area(void *start, void *end, int poison, const char *s)
> {
> + const phys_addr_t pstart = __pa(start);
> + const phys_addr_t pend = __pa(end);
> void *pos;
> unsigned long pages = 0;
>
> @@ -8125,9 +8127,12 @@ unsigned long free_reserved_area(void *start, void *end, int poison, const char
> free_reserved_page(page);
> }
>
> - if (pages && s)
> + if (pages && s) {
> pr_info("Freeing %s memory: %ldK\n",
> s, pages << (PAGE_SHIFT - 10));
> + pr_debug("[%pa-%pa] %pS\n", &pstart, &pend,
> + (void *)__RET_IP_);
> + }
>
> return pages;
> }
>

Acked-by: David Hildenbrand <david@xxxxxxxxxx>

Thanks!

--
Thanks,

David / dhildenb