search for: mc_handle_swap_pt

...d to check the > reference count to see that a page is not being used (gup, compaction, > migration, etc.). Clean up the code so the reference count doesn't need to > be treated specially for device private pages, leaving DAX as still being > a special case. What about the check in mc_handle_swap_pte()? mm/memcontrol.c: 5513 /* 5514 * MEMORY_DEVICE_PRIVATE means ZONE_DEVICE page and which have 5515 * a refcount of 1 when free (unlike normal page) 5516 */ 5517 if (!page_ref_add_unless(page, 1, 1)) 5518...

ZONE_DEVICE struct pages have an extra reference count that complicates the code for put_page() and several places in the kernel that need to check the reference count to see that a page is not being used (gup, compaction, migration, etc.). Clean up the code so the reference count doesn't need to be treated specially for device private pages, leaving DAX as still being a special case.

...ge *page); +#else +static inline void free_zone_device_page(struct page *page) +{ +} +#endif + #endif /* __MM_INTERNAL_H */ diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 3a24e3b619f5..affab09fe35e 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -5553,17 +5553,12 @@ static struct page *mc_handle_swap_pte(struct vm_area_struct *vma, return NULL; /* - * Handle MEMORY_DEVICE_PRIVATE which are ZONE_DEVICE page belonging to - * a device and because they are not accessible by CPU they are store - * as special swap entry in the CPU page table. + * Device private pages are not accessible by the...