From 7ec7096b8577d3b899c1dae456a414f2d08c7ddb Mon Sep 17 00:00:00 2001 From: Pasha Tatashin Date: Tue, 17 Jan 2023 20:46:17 +0000 Subject: [PATCH] mm/page_ext: init page_ext early if there are no deferred struct pages 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@soleen.com: fix build with CONFIG_PAGE_EXTENSION=n] Link: https://lkml.kernel.org/r/20230118155251.2522985-1-pasha.tatashin@soleen.com Link: https://lkml.kernel.org/r/20230117204617.1553748-1-pasha.tatashin@soleen.com Signed-off-by: Pasha Tatashin Acked-by: Mike Rapoport (IBM) Acked-by: Vlastimil Babka Cc: Charan Teja Kalla Cc: David Hildenbrand Cc: Li Zhe Cc: Michal Hocko Signed-off-by: Andrew Morton --- include/linux/page_ext.h | 2 ++ init/main.c | 6 +++--- mm/page_alloc.c | 6 +++++- mm/page_ext.c | 2 +- 4 files changed, 11 insertions(+), 5 deletions(-) diff --git a/include/linux/page_ext.h b/include/linux/page_ext.h index 67314f6..bc2e39090 100644 --- a/include/linux/page_ext.h +++ b/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 /* diff --git a/init/main.c b/init/main.c index e1c3911..64cd2ff 100644 --- a/init/main.c +++ b/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_freeable(void) 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(); diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 0cfad30..ecb9e9a 100644 --- a/mm/page_alloc.c +++ b/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(unsigned long size, int nid, unsigned long zone 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); diff --git a/mm/page_ext.c b/mm/page_ext.c index e2c22ff..dc1626b 100644 --- a/mm/page_ext.c +++ b/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; -- 2.7.4