diff options
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/mm.h | 2 | ||||
| -rw-r--r-- | include/linux/mm_types.h | 14 | ||||
| -rw-r--r-- | include/linux/page_ref.h | 26 | ||||
| -rw-r--r-- | include/linux/pagemap.h | 8 |
4 files changed, 27 insertions, 23 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index 727f799757ab..1193a54ea2b3 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -734,7 +734,7 @@ static inline void get_page(struct page *page) page = compound_head(page); /* * Getting a normal page or the head of a compound page - * requires to already have an elevated page->_count. + * requires to already have an elevated page->_refcount. */ VM_BUG_ON_PAGE(page_ref_count(page) <= 0, page); page_ref_inc(page); diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index c2d75b4fa86c..1fda9c99ef95 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -73,9 +73,9 @@ struct page { unsigned long counters; #else /* - * Keep _count separate from slub cmpxchg_double data. - * As the rest of the double word is protected by - * slab_lock but _count is not. + * Keep _refcount separate from slub cmpxchg_double + * data. As the rest of the double word is protected by + * slab_lock but _refcount is not. */ unsigned counters; #endif @@ -97,7 +97,11 @@ struct page { }; int units; /* SLOB */ }; - atomic_t _count; /* Usage count, see below. */ + /* + * Usage count, *USE WRAPPER FUNCTION* + * when manual accounting. See page_ref.h + */ + atomic_t _refcount; }; unsigned int active; /* SLAB */ }; @@ -248,7 +252,7 @@ struct page_frag_cache { __u32 offset; #endif /* we maintain a pagecount bias, so that we dont dirty cache line - * containing page->_count every time we allocate a fragment. + * containing page->_refcount every time we allocate a fragment. */ unsigned int pagecnt_bias; bool pfmemalloc; diff --git a/include/linux/page_ref.h b/include/linux/page_ref.h index e596d5d9540e..8b5e0a9f2431 100644 --- a/include/linux/page_ref.h +++ b/include/linux/page_ref.h @@ -63,17 +63,17 @@ static inline void __page_ref_unfreeze(struct page *page, int v) static inline int page_ref_count(struct page *page) { - return atomic_read(&page->_count); + return atomic_read(&page->_refcount); } static inline int page_count(struct page *page) { - return atomic_read(&compound_head(page)->_count); + return atomic_read(&compound_head(page)->_refcount); } static inline void set_page_count(struct page *page, int v) { - atomic_set(&page->_count, v); + atomic_set(&page->_refcount, v); if (page_ref_tracepoint_active(__tracepoint_page_ref_set)) __page_ref_set(page, v); } @@ -89,35 +89,35 @@ static inline void init_page_count(struct page *page) static inline void page_ref_add(struct page *page, int nr) { - atomic_add(nr, &page->_count); + atomic_add(nr, &page->_refcount); if (page_ref_tracepoint_active(__tracepoint_page_ref_mod)) __page_ref_mod(page, nr); } static inline void page_ref_sub(struct page *page, int nr) { - atomic_sub(nr, &page->_count); + atomic_sub(nr, &page->_refcount); if (page_ref_tracepoint_active(__tracepoint_page_ref_mod)) __page_ref_mod(page, -nr); } static inline void page_ref_inc(struct page *page) { - atomic_inc(&page->_count); + atomic_inc(&page->_refcount); if (page_ref_tracepoint_active(__tracepoint_page_ref_mod)) __page_ref_mod(page, 1); } static inline void page_ref_dec(struct page *page) { - atomic_dec(&page->_count); + atomic_dec(&page->_refcount); if (page_ref_tracepoint_active(__tracepoint_page_ref_mod)) __page_ref_mod(page, -1); } static inline int page_ref_sub_and_test(struct page *page, int nr) { - int ret = atomic_sub_and_test(nr, &page->_count); + int ret = atomic_sub_and_test(nr, &page->_refcount); if (page_ref_tracepoint_active(__tracepoint_page_ref_mod_and_test)) __page_ref_mod_and_test(page, -nr, ret); @@ -126,7 +126,7 @@ static inline int page_ref_sub_and_test(struct page *page, int nr) static inline int page_ref_dec_and_test(struct page *page) { - int ret = atomic_dec_and_test(&page->_count); + int ret = atomic_dec_and_test(&page->_refcount); if (page_ref_tracepoint_active(__tracepoint_page_ref_mod_and_test)) __page_ref_mod_and_test(page, -1, ret); @@ -135,7 +135,7 @@ static inline int page_ref_dec_and_test(struct page *page) static inline int page_ref_dec_return(struct page *page) { - int ret = atomic_dec_return(&page->_count); + int ret = atomic_dec_return(&page->_refcount); if (page_ref_tracepoint_active(__tracepoint_page_ref_mod_and_return)) __page_ref_mod_and_return(page, -1, ret); @@ -144,7 +144,7 @@ static inline int page_ref_dec_return(struct page *page) static inline int page_ref_add_unless(struct page *page, int nr, int u) { - int ret = atomic_add_unless(&page->_count, nr, u); + int ret = atomic_add_unless(&page->_refcount, nr, u); if (page_ref_tracepoint_active(__tracepoint_page_ref_mod_unless)) __page_ref_mod_unless(page, nr, ret); @@ -153,7 +153,7 @@ static inline int page_ref_add_unless(struct page *page, int nr, int u) static inline int page_ref_freeze(struct page *page, int count) { - int ret = likely(atomic_cmpxchg(&page->_count, count, 0) == count); + int ret = likely(atomic_cmpxchg(&page->_refcount, count, 0) == count); if (page_ref_tracepoint_active(__tracepoint_page_ref_freeze)) __page_ref_freeze(page, count, ret); @@ -165,7 +165,7 @@ static inline void page_ref_unfreeze(struct page *page, int count) VM_BUG_ON_PAGE(page_count(page) != 0, page); VM_BUG_ON(count == 0); - atomic_set(&page->_count, count); + atomic_set(&page->_refcount, count); if (page_ref_tracepoint_active(__tracepoint_page_ref_unfreeze)) __page_ref_unfreeze(page, count); } diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 7e1ab155c67c..fe1513ffb7bf 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -90,12 +90,12 @@ void release_pages(struct page **pages, int nr, bool cold); /* * speculatively take a reference to a page. - * If the page is free (_count == 0), then _count is untouched, and 0 - * is returned. Otherwise, _count is incremented by 1 and 1 is returned. + * If the page is free (_refcount == 0), then _refcount is untouched, and 0 + * is returned. Otherwise, _refcount is incremented by 1 and 1 is returned. * * This function must be called inside the same rcu_read_lock() section as has * been used to lookup the page in the pagecache radix-tree (or page table): - * this allows allocators to use a synchronize_rcu() to stabilize _count. + * this allows allocators to use a synchronize_rcu() to stabilize _refcount. * * Unless an RCU grace period has passed, the count of all pages coming out * of the allocator must be considered unstable. page_count may return higher @@ -111,7 +111,7 @@ void release_pages(struct page **pages, int nr, bool cold); * 2. conditionally increment refcount * 3. check the page is still in pagecache (if no, goto 1) * - * Remove-side that cares about stability of _count (eg. reclaim) has the + * Remove-side that cares about stability of _refcount (eg. reclaim) has the * following (with tree_lock held for write): * A. atomically check refcount is correct and set it to 0 (atomic_cmpxchg) * B. remove page from pagecache |