Revert "mm: create a separate slab for page->ptl allocation"

This reverts commit ea1e7ed. Al points out that while the commit *does* actually create a separate slab for the page->ptl allocation, that slab is never actually used, and the code continues to use kmalloc/kfree. Damien Wyart points out that the original patch did have the conversion to use kmem_cache_alloc/free, so it got lost somewhere on its way to me. Revert the half-arsed attempt that didn't do anything. If we really do want the special slab (remember: this is all relevant just for debug builds, so it's not necessarily all that critical) we might as well redo the patch fully. Reported-by: Al Viro <[email protected]> Acked-by: Andrew Morton <[email protected]> Cc: Kirill A Shutemov <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
maraz · Nov 20, 2013 · 8b2e9b7 · 8b2e9b7
1 parent b5898cd
commit 8b2e9b7
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Showing 3 changed files with 1 addition and 17 deletions.
diff --git a/include/linux/mm.h b/include/linux/mm.h
@@ -1318,7 +1318,6 @@ static inline pmd_t *pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long a
 
 #if USE_SPLIT_PTE_PTLOCKS
 #if BLOATED_SPINLOCKS
-void __init ptlock_cache_init(void);
 extern bool ptlock_alloc(struct page *page);
 extern void ptlock_free(struct page *page);
 
@@ -1327,7 +1326,6 @@ static inline spinlock_t *ptlock_ptr(struct page *page)
 	return page->ptl;
 }
 #else /* BLOATED_SPINLOCKS */
-static inline void ptlock_cache_init(void) {}
 static inline bool ptlock_alloc(struct page *page)
 {
 	return true;
@@ -1380,17 +1378,10 @@ static inline spinlock_t *pte_lockptr(struct mm_struct *mm, pmd_t *pmd)
 {
 	return &mm->page_table_lock;
 }
-static inline void ptlock_cache_init(void) {}
 static inline bool ptlock_init(struct page *page) { return true; }
 static inline void pte_lock_deinit(struct page *page) {}
 #endif /* USE_SPLIT_PTE_PTLOCKS */
 
-static inline void pgtable_init(void)
-{
-	ptlock_cache_init();
-	pgtable_cache_init();
-}
-
 static inline bool pgtable_page_ctor(struct page *page)
 {
 	inc_zone_page_state(page, NR_PAGETABLE);

diff --git a/init/main.c b/init/main.c
@@ -476,7 +476,7 @@ static void __init mm_init(void)
 	mem_init();
 	kmem_cache_init();
 	percpu_init_late();
-	pgtable_init();
+	pgtable_cache_init();
 	vmalloc_init();
 }
 

diff --git a/mm/memory.c b/mm/memory.c
@@ -4272,13 +4272,6 @@ void copy_user_huge_page(struct page *dst, struct page *src,
 #endif /* CONFIG_TRANSPARENT_HUGEPAGE || CONFIG_HUGETLBFS */
 
 #if USE_SPLIT_PTE_PTLOCKS && BLOATED_SPINLOCKS
-static struct kmem_cache *page_ptl_cachep;
-void __init ptlock_cache_init(void)
-{
-	page_ptl_cachep = kmem_cache_create("page->ptl", sizeof(spinlock_t), 0,
-			SLAB_PANIC, NULL);
-}
-
 bool ptlock_alloc(struct page *page)
 {
 	spinlock_t *ptl;