diff options
Diffstat (limited to 'arch/x86/mm')
| -rw-r--r-- | arch/x86/mm/pageattr.c | 35 |
1 files changed, 25 insertions, 10 deletions
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index 831462c3bc35..e5d29a112d00 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -411,20 +411,29 @@ void __init cpa_init(void) static int split_large_page(pte_t *kpte, unsigned long address) { unsigned long flags, pfn, pfninc = 1; - gfp_t gfp_flags = GFP_KERNEL; unsigned int i, level; pte_t *pbase, *tmp; pgprot_t ref_prot; struct page *base; -#ifdef CONFIG_DEBUG_PAGEALLOC - gfp_flags = GFP_ATOMIC | __GFP_NOWARN; -#endif - base = alloc_pages(gfp_flags, 0); - if (!base) + /* + * Get a page from the pool. The pool list is protected by the + * pgd_lock, which we have to take anyway for the split + * operation: + */ + spin_lock_irqsave(&pgd_lock, flags); + if (list_empty(&page_pool)) { + spin_unlock_irqrestore(&pgd_lock, flags); return -ENOMEM; + } + + base = list_first_entry(&page_pool, struct page, lru); + list_del(&base->lru); + pool_pages--; + + if (pool_pages < pool_low) + pool_low = pool_pages; - spin_lock_irqsave(&pgd_lock, flags); /* * Check for races, another CPU might have split this page * up for us already: @@ -469,11 +478,17 @@ static int split_large_page(pte_t *kpte, unsigned long address) base = NULL; out_unlock: + /* + * If we dropped out via the lookup_address check under + * pgd_lock then stick the page back into the pool: + */ + if (base) { + list_add(&base->lru, &page_pool); + pool_pages++; + } else + pool_used++; spin_unlock_irqrestore(&pgd_lock, flags); - if (base) - __free_pages(base, 0); - return 0; } |