memmap_init_zone_device() currently mixes refcount policy, core ZONE_DEVICE page setup, and pageblock metadata handling in a single helper.
Factor the refcount policy into zone_device_page_init_refcount(), move the common page initialization into __zone_device_page_init(), split pageblock handling into zone_device_page_init_pageblock(), and wrap the existing slow path in zone_device_page_init_slow(). This keeps the slow-path behaviour unchanged and gives later patches reusable helper boundaries. No functional change intended. Signed-off-by: Li Zhe <[email protected]> --- mm/mm_init.c | 64 +++++++++++++++++++++++++++++++++------------------- 1 file changed, 41 insertions(+), 23 deletions(-) diff --git a/mm/mm_init.c b/mm/mm_init.c index f9f8e1af921c..4ba506df93bc 100644 --- a/mm/mm_init.c +++ b/mm/mm_init.c @@ -987,11 +987,36 @@ static void __init memmap_init(void) } #ifdef CONFIG_ZONE_DEVICE -static void __ref __init_zone_device_page(struct page *page, unsigned long pfn, +static inline int zone_device_page_init_refcount( + const struct dev_pagemap *pgmap) +{ + /* + * ZONE_DEVICE pages other than MEMORY_TYPE_GENERIC are released + * directly to the driver page allocator which will set the page count + * to 1 when allocating the page. + * + * MEMORY_TYPE_GENERIC and MEMORY_TYPE_FS_DAX pages automatically have + * their refcount reset to one whenever they are freed (ie. after + * their refcount drops to 0). + */ + switch (pgmap->type) { + case MEMORY_DEVICE_FS_DAX: + case MEMORY_DEVICE_PRIVATE: + case MEMORY_DEVICE_COHERENT: + case MEMORY_DEVICE_PCI_P2PDMA: + return 0; + case MEMORY_DEVICE_GENERIC: + return 1; + default: + WARN_ONCE(1, "Unknown memory type!"); + return 1; + } +} + +static void __ref __zone_device_page_init(struct page *page, unsigned long pfn, unsigned long zone_idx, int nid, struct dev_pagemap *pgmap) { - __init_single_page(page, pfn, zone_idx, nid); /* @@ -1010,7 +1035,11 @@ static void __ref __init_zone_device_page(struct page *page, unsigned long pfn, */ page_folio(page)->pgmap = pgmap; page->zone_device_data = NULL; +} +static void __ref zone_device_page_init_pageblock(struct page *page, + unsigned long pfn) +{ /* * Mark the block movable so that blocks are reserved for * movable at startup. This will force kernel allocations @@ -1025,27 +1054,16 @@ static void __ref __init_zone_device_page(struct page *page, unsigned long pfn, init_pageblock_migratetype(page, MIGRATE_MOVABLE, false); cond_resched(); } +} - /* - * ZONE_DEVICE pages other than MEMORY_TYPE_GENERIC are released - * directly to the driver page allocator which will set the page count - * to 1 when allocating the page. - * - * MEMORY_TYPE_GENERIC and MEMORY_TYPE_FS_DAX pages automatically have - * their refcount reset to one whenever they are freed (ie. after - * their refcount drops to 0). - */ - switch (pgmap->type) { - case MEMORY_DEVICE_FS_DAX: - case MEMORY_DEVICE_PRIVATE: - case MEMORY_DEVICE_COHERENT: - case MEMORY_DEVICE_PCI_P2PDMA: +static void __ref zone_device_page_init_slow(struct page *page, + unsigned long pfn, unsigned long zone_idx, int nid, + struct dev_pagemap *pgmap) +{ + __zone_device_page_init(page, pfn, zone_idx, nid, pgmap); + if (!zone_device_page_init_refcount(pgmap)) set_page_count(page, 0); - break; - - case MEMORY_DEVICE_GENERIC: - break; - } + zone_device_page_init_pageblock(page, pfn); } /* @@ -1084,7 +1102,7 @@ static void __ref memmap_init_compound(struct page *head, for (pfn = head_pfn + 1; pfn < end_pfn; pfn++) { struct page *page = pfn_to_page(pfn); - __init_zone_device_page(page, pfn, zone_idx, nid, pgmap); + zone_device_page_init_slow(page, pfn, zone_idx, nid, pgmap); prep_compound_tail(page, head, order); set_page_count(page, 0); } @@ -1120,7 +1138,7 @@ void __ref memmap_init_zone_device(struct zone *zone, for (pfn = start_pfn; pfn < end_pfn; pfn += pfns_per_compound) { struct page *page = pfn_to_page(pfn); - __init_zone_device_page(page, pfn, zone_idx, nid, pgmap); + zone_device_page_init_slow(page, pfn, zone_idx, nid, pgmap); if (pfns_per_compound == 1) continue; -- 2.20.1

