The quilt patch titled Subject: mm/page_ext: init page_ext early if there are no deferred struct pages has been removed from the -mm tree. Its filename was mm-page_ext-init-page_ext-early-if-there-are-no-deferred-struct-pages.patch This patch was dropped because it was merged into the mm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Pasha Tatashin <pasha.tatashin@xxxxxxxxxx> Subject: mm/page_ext: init page_ext early if there are no deferred struct pages Date: Tue, 17 Jan 2023 20:46:17 +0000 page_ext must be initialized after all struct pages are initialized. Therefore, page_ext is initialized after page_alloc_init_late(), and can optionally be initialized earlier via early_page_ext kernel parameter which as a side effect also disables deferred struct pages. Allow to automatically init page_ext early when there are no deferred struct pages in order to be able to use page_ext during kernel boot and track for example page allocations early. [pasha.tatashin@xxxxxxxxxx: fix build with CONFIG_PAGE_EXTENSION=n] Link: https://lkml.kernel.org/r/20230118155251.2522985-1-pasha.tatashin@xxxxxxxxxx Link: https://lkml.kernel.org/r/20230117204617.1553748-1-pasha.tatashin@xxxxxxxxxx Signed-off-by: Pasha Tatashin <pasha.tatashin@xxxxxxxxxx> Acked-by: Mike Rapoport (IBM) <rppt@xxxxxxxxxx> Acked-by: Vlastimil Babka <vbabka@xxxxxxx> Cc: Charan Teja Kalla <quic_charante@xxxxxxxxxxx> Cc: David Hildenbrand <david@xxxxxxxxxx> Cc: Li Zhe <lizhe.67@xxxxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- --- a/include/linux/page_ext.h~mm-page_ext-init-page_ext-early-if-there-are-no-deferred-struct-pages +++ a/include/linux/page_ext.h @@ -29,6 +29,8 @@ struct page_ext_operations { bool need_shared_flags; }; +extern bool deferred_struct_pages; + #ifdef CONFIG_PAGE_EXTENSION /* --- a/init/main.c~mm-page_ext-init-page_ext-early-if-there-are-no-deferred-struct-pages +++ a/init/main.c @@ -855,8 +855,8 @@ static void __init mm_init(void) pgtable_init(); debug_objects_mem_init(); vmalloc_init(); - /* Should be run after vmap initialization */ - if (early_page_ext_enabled()) + /* If no deferred init page_ext now, as vmap is fully initialized */ + if (!deferred_struct_pages) page_ext_init(); /* Should be run before the first non-init thread is created */ init_espfix_bsp(); @@ -1628,7 +1628,7 @@ static noinline void __init kernel_init_ padata_init(); page_alloc_init_late(); /* Initialize page ext after all struct pages are initialized. */ - if (!early_page_ext_enabled()) + if (deferred_struct_pages) page_ext_init(); do_basic_setup(); --- a/mm/page_alloc.c~mm-page_ext-init-page_ext-early-if-there-are-no-deferred-struct-pages +++ a/mm/page_alloc.c @@ -430,6 +430,8 @@ EXPORT_SYMBOL(nr_online_nodes); int page_group_by_mobility_disabled __read_mostly; +bool deferred_struct_pages __meminitdata; + #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT /* * During boot we initialize deferred pages on-demand, as needed, but once @@ -6803,8 +6805,10 @@ void __meminit memmap_init_range(unsigne if (context == MEMINIT_EARLY) { if (overlap_memmap_init(zone, &pfn)) continue; - if (defer_init(nid, pfn, zone_end_pfn)) + if (defer_init(nid, pfn, zone_end_pfn)) { + deferred_struct_pages = true; break; + } } page = pfn_to_page(pfn); --- a/mm/page_ext.c~mm-page_ext-init-page_ext-early-if-there-are-no-deferred-struct-pages +++ a/mm/page_ext.c @@ -92,7 +92,7 @@ unsigned long page_ext_size; static unsigned long total_usage; static struct page_ext *lookup_page_ext(const struct page *page); -bool early_page_ext; +bool early_page_ext __meminitdata; static int __init setup_early_page_ext(char *str) { early_page_ext = true; _ Patches currently in -mm which might be from pasha.tatashin@xxxxxxxxxx are