On Wed, Jun 12, 2024 at 02:04:21AM +0000, Wei Yang wrote:
> Function deferred_[init|free]_pages are only used in
> deferred_init_maxorder(), which makes sure the range to init/free is
> within MAX_ORDER_NR_PAGES size.
>
> With this knowledge, we can simplify these two functions. Since
>
> * only the first pfn could be IS_MAX_ORDER_ALIGNED()
>
> Also since the range passed to deferred_[init|free]_pages is always from
> memblock.memory for those we have already allocated memmap to cover,
> pfn_valid() always return true. Then we can remove related check.
>
> Signed-off-by: Wei Yang <richard.weiyang@xxxxxxxxx>
> CC: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
> CC: Mike Rapoport (IBM) <rppt@xxxxxxxxxx>
> CC: David Hildenbrand <david@xxxxxxxxxx>
Reviewed-by: Mike Rapoport (IBM) <rppt@xxxxxxxxxx>
> ---
> mm/mm_init.c | 63 +++++++---------------------------------------------
> 1 file changed, 8 insertions(+), 55 deletions(-)
>
> diff --git a/mm/mm_init.c b/mm/mm_init.c
> index c152c60eca3d..63d70fc60705 100644
> --- a/mm/mm_init.c
> +++ b/mm/mm_init.c
> @@ -1911,7 +1911,7 @@ unsigned long __init node_map_pfn_alignment(void)
> }
>
> #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
> -static void __init deferred_free_range(unsigned long pfn,
> +static void __init deferred_free_pages(unsigned long pfn,
> unsigned long nr_pages)
> {
> struct page *page;
> @@ -1950,69 +1950,22 @@ static inline void __init pgdat_init_report_one_done(void)
> complete(&pgdat_init_all_done_comp);
> }
>
> -/*
> - * Returns true if page needs to be initialized or freed to buddy allocator.
> - *
> - * We check if a current MAX_PAGE_ORDER block is valid by only checking the
> - * validity of the head pfn.
> - */
> -static inline bool __init deferred_pfn_valid(unsigned long pfn)
> -{
> - if (IS_MAX_ORDER_ALIGNED(pfn) && !pfn_valid(pfn))
> - return false;
> - return true;
> -}
> -
> -/*
> - * Free pages to buddy allocator. Try to free aligned pages in
> - * MAX_ORDER_NR_PAGES sizes.
> - */
> -static void __init deferred_free_pages(unsigned long pfn,
> - unsigned long end_pfn)
> -{
> - unsigned long nr_free = 0;
> -
> - for (; pfn < end_pfn; pfn++) {
> - if (!deferred_pfn_valid(pfn)) {
> - deferred_free_range(pfn - nr_free, nr_free);
> - nr_free = 0;
> - } else if (IS_MAX_ORDER_ALIGNED(pfn)) {
> - deferred_free_range(pfn - nr_free, nr_free);
> - nr_free = 1;
> - } else {
> - nr_free++;
> - }
> - }
> - /* Free the last block of pages to allocator */
> - deferred_free_range(pfn - nr_free, nr_free);
> -}
> -
> /*
> * Initialize struct pages. We minimize pfn page lookups and scheduler checks
> * by performing it only once every MAX_ORDER_NR_PAGES.
> * Return number of pages initialized.
> */
> -static unsigned long __init deferred_init_pages(struct zone *zone,
> - unsigned long pfn,
> - unsigned long end_pfn)
> +static unsigned long __init deferred_init_pages(struct zone *zone,
> + unsigned long pfn,
> + unsigned long end_pfn)
> {
> int nid = zone_to_nid(zone);
> - unsigned long nr_pages = 0;
> + unsigned long nr_pages = end_pfn - pfn;
> int zid = zone_idx(zone);
> - struct page *page = NULL;
> + struct page *page = pfn_to_page(pfn);
>
> - for (; pfn < end_pfn; pfn++) {
> - if (!deferred_pfn_valid(pfn)) {
> - page = NULL;
> - continue;
> - } else if (!page || IS_MAX_ORDER_ALIGNED(pfn)) {
> - page = pfn_to_page(pfn);
> - } else {
> - page++;
> - }
> + for (; pfn < end_pfn; pfn++, page++)
> __init_single_page(page, pfn, zid, nid);
> - nr_pages++;
> - }
> return nr_pages;
> }
>
> @@ -2096,7 +2049,7 @@ deferred_init_maxorder(u64 *i, struct zone *zone, unsigned long *start_pfn,
> break;
>
> t = min(mo_pfn, epfn);
> - deferred_free_pages(spfn, t);
> + deferred_free_pages(spfn, t - spfn);
>
> if (mo_pfn <= epfn)
> break;
> --
> 2.34.1
>
--
Sincerely yours,
Mike.
