From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755435AbYIIWne (ORCPT ); Tue, 9 Sep 2008 18:43:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753457AbYIIWnY (ORCPT ); Tue, 9 Sep 2008 18:43:24 -0400 Received: from gw.goop.org ([64.81.55.164]:35010 "EHLO mail.goop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751691AbYIIWnY (ORCPT ); Tue, 9 Sep 2008 18:43:24 -0400 Message-ID: <48C6FC0A.7070102@goop.org> Date: Tue, 09 Sep 2008 15:43:22 -0700 From: Jeremy Fitzhardinge User-Agent: Thunderbird 2.0.0.16 (X11/20080723) MIME-Version: 1.0 To: Alex Nixon CC: Linux Kernel Mailing List , Ingo Molnar , Andrew Morton Subject: [PATCH 1/2] mm: define USE_SPLIT_PTLOCKS rather than repeating expression References: <> <1220959508-13806-1-git-send-email-alex.nixon@citrix.com> <48C6BB00.9040607@goop.org> <48C6CCD7.8030800@citrix.com> <48C6DE6E.1070804@goop.org> <48C6F80E.8010509@citrix.com> In-Reply-To: <48C6F80E.8010509@citrix.com> X-Enigmail-Version: 0.95.7 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Define USE_SPLIT_PTLOCKS as a constant expression rather than repeating "NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS" all over the place. Signed-off-by: Jeremy Fitzhardinge --- arch/x86/xen/mmu.c | 2 +- include/linux/mm.h | 6 +++--- include/linux/mm_types.h | 10 ++++++---- include/linux/sched.h | 6 +++--- 4 files changed, 13 insertions(+), 11 deletions(-) =================================================================== --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -805,7 +805,7 @@ { spinlock_t *ptl = NULL; -#if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS +#if USE_SPLIT_PTLOCKS ptl = __pte_lockptr(page); spin_lock_nest_lock(ptl, &mm->page_table_lock); #endif =================================================================== --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -914,7 +914,7 @@ } #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 @@ -927,14 +927,14 @@ } 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) { =================================================================== --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -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 @@ * 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 */ =================================================================== --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -352,7 +352,7 @@ 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 @@ #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 @@ #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))