Commit f7d0b926 authored by Jeremy Fitzhardinge's avatar Jeremy Fitzhardinge Committed by Ingo Molnar
Browse files

mm: define USE_SPLIT_PTLOCKS rather than repeating expression 



Define USE_SPLIT_PTLOCKS as a constant expression rather than repeating
"NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS" all over the place.

Signed-off-by: default avatarJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: default avatarHugh Dickins <hugh@veritas.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent adee14b2

arch/x86/xen/mmu.c

+1 −1
Original line number Diff line number Diff line
@@ -646,7 +646,7 @@ static spinlock_t *lock_pte(struct page *page) 
{

	spinlock_t *ptl = NULL;



#if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS

#if USE_SPLIT_PTLOCKS

	ptl = __pte_lockptr(page);

	spin_lock(ptl);

#endif

include/linux/mm.h

+3 −3
Original line number Diff line number Diff line
@@ -919,7 +919,7 @@ static inline pmd_t *pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long a 
}

#endif /* CONFIG_MMU && !__ARCH_HAS_4LEVEL_HACK */



#if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS

#if USE_SPLIT_PTLOCKS

/*

 * We tuck a spinlock to guard each pagetable page into its struct page,

 * at page->private, with BUILD_BUG_ON to make sure that this will not
@@ -932,14 +932,14 @@ static inline pmd_t *pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long a 
} while (0)

#define pte_lock_deinit(page)	((page)->mapping = NULL)

#define pte_lockptr(mm, pmd)	({(void)(mm); __pte_lockptr(pmd_page(*(pmd)));})

#else

#else	/* !USE_SPLIT_PTLOCKS */

/*

 * We use mm->page_table_lock to guard all pagetable pages of the mm.

 */

#define pte_lock_init(page)	do {} while (0)

#define pte_lock_deinit(page)	do {} while (0)

#define pte_lockptr(mm, pmd)	({(void)(pmd); &(mm)->page_table_lock;})

#endif /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */

#endif /* USE_SPLIT_PTLOCKS */



static inline void pgtable_page_ctor(struct page *page)

{

include/linux/mm_types.h

+6 −4
Original line number Diff line number Diff line
@@ -21,11 +21,13 @@ 


struct address_space;



#if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS

#define USE_SPLIT_PTLOCKS	(NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS)



#if USE_SPLIT_PTLOCKS

typedef atomic_long_t mm_counter_t;

#else  /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */

#else  /* !USE_SPLIT_PTLOCKS */

typedef unsigned long mm_counter_t;

#endif /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */

#endif /* !USE_SPLIT_PTLOCKS */



/*

 * Each physical page in the system has a struct page associated with
@@ -65,7 +67,7 @@ struct page { 
						 * see PAGE_MAPPING_ANON below.

						 */

	    };

#if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS

#if USE_SPLIT_PTLOCKS

	    spinlock_t ptl;

#endif

	    struct kmem_cache *slab;	/* SLUB: Pointer to slab */

include/linux/sched.h

+3 −3
Original line number Diff line number Diff line
@@ -352,7 +352,7 @@ arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr, 
extern void arch_unmap_area(struct mm_struct *, unsigned long);

extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);



#if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS

#if USE_SPLIT_PTLOCKS

/*

 * The mm counters are not protected by its page_table_lock,

 * so must be incremented atomically.
@@ -363,7 +363,7 @@ extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long); 
#define inc_mm_counter(mm, member) atomic_long_inc(&(mm)->_##member)

#define dec_mm_counter(mm, member) atomic_long_dec(&(mm)->_##member)



#else  /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */

#else  /* !USE_SPLIT_PTLOCKS */

/*

 * The mm counters are protected by its page_table_lock,

 * so can be incremented directly.
@@ -374,7 +374,7 @@ extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long); 
#define inc_mm_counter(mm, member) (mm)->_##member++

#define dec_mm_counter(mm, member) (mm)->_##member--



#endif /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */

#endif /* !USE_SPLIT_PTLOCKS */



#define get_mm_rss(mm)					\

	(get_mm_counter(mm, file_rss) + get_mm_counter(mm, anon_rss))